The utilization of gold nanoparticles (AuNPs) has garnered significant attention in recent times, particularly in the field of biomedical research. The utilization of AuNPs in chemical synthesis procedures raises apprehensions regarding their potential toxicity in living organisms, which is inconsistent with their purported eco-friendly and cost-effective aspects. In this investigation, AuNPs were synthesized via the green synthesis approach utilizing Jeju Hallabong peel extract (HPE), a typical fruit variety indigenous to South Korea. The visible-range absorption spectrum of gold nanoparticles from green synthesis (HAuNPs) that are red wine in color occurs at a wavelength of λ = 517 nm. The morphology and particle size distribution were analysed using transmission electron microscopy (TEM) and ImageJ software. The TEM images reveal that the HAuNPs exhibit a high degree of dispersion and uniformity in their spherical shape, with an average size of approximately 7 nm. Moreover, elevating the initial pH level of the mixed solution has an impact on the decrease in particle dimensions, as evidenced by the blue shift observed in the UV-visible spectroscopy absorbance peak. Elevating the reaction temperature may accelerate the synthesis duration. However, it does not exert a substantial impact on the particle dimensions. The outcomes of an avidin-biocytin colorimetric assay provide preliminary analyses of possible sensor tunability using HAuNPs. The cytotoxicity of HAuNPs was evaluated through in vitro studies using the MTT assay on RAW 264.7 cell lines. The results indicated that the HAuNPs exhibited lower cytotoxicity compared to both chemically reduced gold nanoparticles (CAuNPs) and commercially available gold nanoparticles (SAAuNPs).

Diabetic retinopathy (DR) and cataracts (CA) have an early onset in diabetes mellitus (DM) due to the redox imbalance and inflammation triggered by hyperglycemia. Plant-based therapies are characterized by low bioavailability in ocular tissues. The study aimed to investigate the effect of gold nanoparticles phytoreduced with Rutin (AuNPsR), as a possible solution. Insulin, Rutin, and AuNPsR, were administered to an early, six-week rat model of DR and CA. Oxidative stress (MDA, CAT, SOD) was assessed in serum and eye homogenates, and inflammatory cytokines (IL-1 beta, IL-6, TNF alpha) were quantified in ocular tissues. Fundus of retinal arterioles, retina histopathology and lens transmission electron microscopy (TEM), were also performed. DM was linked to constricted retinal arterioles, reduced endogen antioxidants, and eye inflammation. Histologically, retinal wall thickness decreased. TEM showed increased lens opacity and fiber disorganization. Rutin improved retinal arteriolar diameter, while reducing oxidative stress and inflammation. Retinas were moderately edematous. Lens structure was preserved on TEM. Insulin restored retinal arteriolar diameter, while increasing MDA, and amplifying TEM lens opacity. The best outcomes were obtained for AuNPsR, as it improved fundus appearance of retinal arterioles, decreased MDA formation and increased antioxidant capacity. Retinal edema and disorganization in lens fibers were still present.

Nanoparticles (NPs) have uniform chemical composition, size, and morphology. Microorganisms are of great interest in Nanoparticle synthesis. The green production of nanomaterials occurs either intracellularly or extracellularly. Gold and silver nanoparticles are mostly synthesised by the enzymatic degradation of metal ions. The produced NPs are characterized by different instruments such as ultraviolet visible, dynamic light scattering, x-ray diffraction, scanning electron microscope, transmission electron microscope, etc. Our review discusses the various biomedical applications of gold and silver nanoparticles synthesized by microbes via intracellular and extracellular mechanisms.

The Computational theoretical techniques using first principle which make use of the density functional theory as implemented by quantum expresso as well as inter – atomic force constant (IFC) techniques (Born-von Jarman) were used to investigate the phonon dispersion curves of Silver (Ag) and Gold (Au) The results obtained show that for Au, the extension to 1 – 6^th neighbour gave slightly close agreement with the experimental phonon dispersions when compared to the 1 – 5^th neighbor at W_T and L_L symmetry points. The percentage error for Au at W_T are 2.5% and 2.9% ; at point L_L we obtained 0.6% and 0.7% respectively. The Local density Approximation (LDA) results for Ag underestimates the lattice with about 1.6% while the Generalized Gradient Approximation (GGA) overestimates it by 1.9%.

Gold nanoparticles (AuNPs) are promising candidates in various biomedical applications such as sensors, imaging, and cancer therapy. Understanding the influence of AuNPs on lipid membranes is important to assure their safety in the biological environment and to improve their scope in nanomedicine. In this regard, the present study aims to analyze the effects of different concentrations (0.5, 1, and 2 w %) of dodecanethiol functionalized hydrophobic AuNPs on the structure and fluidity of zwitterionic 1-stearoyl-2-oleoyl-sn-glycerol-3-phosphocholine (SOPC) lipid bilayer membranes using Fourier transform infrared (FTIR) spectroscopy and fluorescent spectroscopy. The size of AuNPs was found to be 2.2 ± 1.1 nm using transmission electron microscopy. FTIR results have shown that the AuNPs induced a slight shift in methylene stretching bands, while the band positions of carbonyl and phosphate group stretching were unaffected. Temperature-dependent fluorescent anisotropy measurements have shown that the incorporation of AuNPs up to 2 w % did not affect the lipid order in membranes. Overall, these results indicate that the hydrophobic AuNPs in the studied concentration did not cause any significant alterations in the structure and membrane fluidity, which suggests the suitability of these particles to form liposome-AuNP hybrids for diverse biomedical applications including drug delivery and therapy.

The photocatalytic hydrogen evolution reaction (HER) by water splitting has been studied, using catalysts based on TiO2 nanowires (TiO2NWs), which were synthesized by a hydrothermal procedure. This nanomaterial was subsequently modified by incorporating different loadings of gold nanoparticles (AuNPs) on the surface, previously exfoliated MoS2 nanosheets, and CeO2 nanoparticles (CeO2NPs). These nanomaterials, as well as the different synthesized catalysts, were characterized by electron microscopy (HR-SEM and HR-TEM), XPS, XRD, Raman, Reflectance and BET surface area. HER studies were performed in aqueous solution, under irradiation at different wavelengths, which were selected through the appropriate use of optical filters. The results obtained show that there is a synergistic effect between the different nanomaterials of the catalysts. The specific area of the catalyst, and especially the increased loading of MoS2 and CeO2NPs in the catalyst substantially improved the H2 production. Recyclability studies showed only a decrease in activity of approx. 7% after 15 cycles of use, which opens many possibilities regarding the potential use and scaling of these heterostructures in photocatalytic production of H2 from water.

Modern technologies for recycling electronic waste (e-waste) impose high economic efficiency and environmental safety requirements. Among existing technologies, hydrometallurgy is considered the most promising technology for e-waste recycling. Increasing attention to the chlorination method is associated with the complex recycling of low-grade ores containing noble metals and secondary polymetallic raw materials. In this paper, we propose a new scheme for leaching metals from computer printed circuits (PCBs) pre-crushed in a disintegrator: the processes of chlorine production and hydrochlorination are implemented in one reactor under the action of alternating current (AC) of industrial frequency (50 Hz). It was found that complete leaching of gold is achieved from fine fractions of raw materials containing 0.03% and 0.01% of the gold at an experiment duration of 2 hours, a current density of 0.66 A·cm-2, and a solid/liquid ratio of 8.6 g·L-1. Under the same conditions of the electrochemical leaching process from the fraction of raw material with a gold content of 0.08%, the degree of metal leaching is 80.5%. At the same time, with an increase in the copper content in the raw material from 1.40% to 6.13%, an increase in the degree of its leaching from 84.6% to 95.2%, respectively, is observed. These results will serve as a foundation for developing a complex technology for recovering valuable metals from PCBs.

Accelerated degradation tests (ADT) are widely used in the manufacturing industry to obtain information on the reliability of components and materials, through degrading the lifespan of the product by applying an acceleration factor which causes damage to the material. The main objective is to obtain fast information which is modeled to estimate the characteristics of the material life under normal conditions of use and to save time and expenses. The purpose of this work is to estimate the lifespan distribution of gold nanoparticles stabilized with lipoic acid (GNPs@LA) through accelerated degradation tests applying sodium chloride (NaCl) as an acceleration factor. For this, the synthesis of GNPs@LA was carried out, a constant stress ADT (CSADT) was applied, and the non-linear Wiener process was proposed with random effects, error measures and different covariability for the adjustment of the degradation signals. The information obtained with the test and analysis allows us to obtain the life distribution in GNPs@LA, the results make possible to determine the guaranteed time for a possible commercialization and successful application based on the stability of the material. In addition, for the evaluation and selection of the model, the Akaike and Bootstraping criteria were used.

Gold nanoparticles have been indicated for use in a diagnostic and/or therapeutic role in several cancer types. The use of gold nanorods (AuNRs) with a surface plasmon resonance (SPR) in the second Near-Infrared II (NIR-II) optical window promises deeper anatomical penetration through increased maximum permissible exposure and lower optical attenuation. In this study, the targeting efficiency of anti-epidermal growth factor receptor (EGFR) antibody functionalised AuNRs with an SPR at 1064 nm was evaluated in vitro. Four cell lines, KYSE-30, CAL-27, Hep-G2 and MCF-7 that either over or under expressed EGFR were used. This expression was confirmed by flow cytometry and immunofluorescence. Cytotoxicity assays showed no AuNRs toxicity to both EGFR positive and EGFR negative cell lines up to a concentrations of 19 µg/ml. Optical microscopy demonstrated a significant difference (p<0.0001) between targeted AuNRs (tAuNRs) and untargeted AuNRs (uAuNRs) in all four cancer cell lines. This study demonstrates that anti-EGFR functionalisation significantly increased the number of tAuNRs associated with each EGFR positive cancer cell. This successful targeting highlights the use of tAuNRs for molecular photoacoustic imaging or tumour treatment through plasmonic photothermal therapy.

Carbonaceous material (CM) is common in meta-sediments and is generally interpreted to be intimately associated with gold mineralization. For the Bumo deposit in Hainan Province, South China, CM is mainly hosted by greenschist facies- to amphibolite-facies metamophic rocks of the Paleo- to Mesoproterozoic Baoban Group and by auriferous veins and is used as an important gold prospecting indicator. However, the genesis of CM and the relationship with gold mineralization are still not clear. Field work and thin section observation indicates that two types of CM occur, i.e., layered and veinlet. Layered CM, up to meters thick, prevails in the deposit. More importantly, Au-bearing sulfides are commonly distributed along the boundary between the quartz veins and layered CM. In contrast, veinlet CM, co-precipitated with gold and sulfides, has the thickness of micro- to centi- meters, and these thin veins occur in quartz veins and hydrothermally altered rocks. Scanning Electron Microscope (SEM) analysis indicates that layered CM has a stringy shape and laminate structure, while veinlet CM occurs as isometric particles. Raman carbonaceous material geothermometer indicates that layered CM with high maturity is formed at elevated temperatures of 400 – 550°C, consistent with X-ray diffraction (XRD) analysis. In contrast, veinlet CM with low maturity is formed at 200 – 350°C, generally consistent with gold mineralization. In addition, layered CM has δ13C values ranging from -30 to -20%, demonstrating a biogenic origin. Consequently, it is interpreted that layered CM is formed by a pre-ore metamorphic event during Caledonian, and its reducing nature promotes gold precipitation via destabilization of aqueous Au bisulfide complexes or facilitating sulfidation. Veinlet CM is hydrothermal origin, and its precipitation modified the chemical conditions of ore fluids, leading to the destabilization of Au complexes and thus favorable for mineralization.

A simple and rapid positive–negative colorimetric approach to determine the presence of antimony ions based on the use of gold nanoparticles conjugated with oligonucleotide (poly-A sequence) is developed. Colorimetric measurements reveal that the aggregates of modified gold nanoparticles were afforded after adding antimony ions, thus changing the solution color from pink to blue. The results of aptamer’s interaction on the gold nanoparticle surface with target analyte can be detected either by photometry or by the naked eye. The realized assay provides rapid (2 min), sensitive (detection limit 10 ng/mL), specific, and precise (variation coefficient less than 3.8%) detection of antimony (III) in drinking water

While deforestation rates decline globally they are rising in the Western Amazon. Artisanal-scale gold mining (ASGM) is a large cause of this deforestation and brings with it extensive environmental, social, governance, and public health impacts, including large carbon emissions and mercury pollution. Underlying ASGM is a broad network of factors that influence its growth, distribution, and practices such as poverty, flows of legal and illegal capital, conflicting governance, and global economic trends. Despite its central role in land use and land cover change in the Western Amazon and the severity of its social and environmental impacts, it is relatively poorly studied. While ASGM in Southeastern Peru has been quantified previously, doing so is difficult due to the heterogeneous nature of the resulting landscape. Using a novel approach to classify mining that relies on a fusion of CLASlite and the Global Forest Change dataset, two Landsat-based deforestation detection tools, we sought to quantify ASGM-caused deforestation in the period 1984–2017 in the southern Peruvian Amazon and examine trends in the geography, methods, and impacts of ASGM across that time. We identify nearly 100,000 ha of deforestation due to ASGM in the 34-year study period, an increase of 21% compared to previous estimates. Further, we find that 10% of that deforestation occurred in 2017, the highest annual amount of deforestation in the study period, with 53% occurring since 2011. Finally, we demonstrate that not all mining is created equal by examining key patterns and changes in ASGM activity and techniques through time and space. We discuss their connections with, and impacts on, socio-economic factors, such as land tenure, infrastructure, international markets, governance efforts, and social and environmental impacts.

A great improvement in food safety and quality controls worldwide has been achieved through the development of biosensing platforms. Foodborne pathogens continue to cause serious outbreaks due to the ingestion of contaminated food. The development of new, sensitive, portable, high-throughput, and automated platforms is a primary objective to allow detection of pathogens and their toxins in foods. Listeria monocytogenes is one common foodborne pathogen. Major outbreaks of listeriosis have been caused by a variety of foods, including milk, soft cheeses, meat, fermented sausages, poultry, seafood and vegetable products. Due to its high sensitivity and easy setup, electrochemical impedance spectroscopy (EIS) has been extensively applied for biosensor fabrication and in particular in the field of microbiology as a mean to detect and quantify foodborne bacteria. Here we describe a miniaturized, portable EIS platform consisting of a microfluidic device with EIS sensors for the detection of L. monocytogenes in milk samples, connected to a portable impedance analyzer for on-field application in clinical and food diagnostics but also for biosecurity purposes. To achieve this goal microelectrodes were functionalized with antibodies specific for L. monocytogenes. The binding and detection of L. monocytogenes was achieved in the range 2.2 x 103 cfu/ml to 1 x 102 with a Limit of Detection (LoD) of 5.5 cfu/ml.

The lectin found in the tubers of the Winter Aconite (Eranthis hyemalis) plant (EHL) is a Type II Ribosome Inactivating Protein (RIP); type II RIPs have shown anti-cancer properties, and have great potential as therapeutic agents. Similarly, colloidal gold nanoparticles are successfully used in biomedical applications as gold nanoparticles can be functionalised with ligands with high affinity and specificity for target cells to create therapeutic and imaging agents. Herein we present the synthesis and characterization of gold nanoparticles conjugated with EHL. The aim was to establish the viability of the conjugate and perform a set of initial assays to establish whether the biological effect of EHL is altered by the conjugation. The biological assays were performed in Caenorhabditis elegans, a free living nematode commonly used for toxicological studies; previous work from some of the authors using first life stage (L1) nematodes has shown that EHL has a strong biocidal effect on C. elegans. Gold nanoparticles functionalised with EHL (AuNPs@EHL) were successfully synthesised by bioconjugation with citrate gold nanoparticles (AuNPs@Citrate); the conjugates were analysed by UV-Vis spectroscopy, Dynamic Light Scattering (DLS), Zeta Potential analysis and Transmission Electron Microscopy (TEM). Results indicate that an optimal functionalisation was achieved with the addition of 100 µL of EHL (concentration 1090 ± 40 µg/mL) over 5 mL of AuNPs (concentration [Au0] = 0.8 mM). Biological assays on the effect of AuNPs@EHL on C. elegans were performed, using first life stage (L1) and pre-adult stage (L4) nematodes. Citrate gold nanoparticles did not have any obvious effect on the nematodes. For L1 stage nematodes, the assays show that conjugation with gold nanoparticles reduced the biological effect of EHL on C. elegans. As lectin binding activity is essential for the natural protein to bind and allow entry to cells, conformational changes due to conjugation may have affected this binding affinity. For L4 stage nematodes, both EHL alone and AuNPs@EHL showed biological activity, and reproductive delays and reduced fecundity were observed in both cases. These assays indicate that EHL can be conjugated to gold nanoparticles and retain elements of biocidal activity.

Tsygankoite, ideally Mn8Tl8Hg2(Sb21Pb2Tl)Σ24S48, is a new sulfosalt discovered at the Vorontsovskoe gold deposit, Northern Urals, Russia. It occurs as lath-like elongated crystals up to 0.2 mm embedded in calcite-dolomite-clinochlore matrix. The associating minerals also include aktashite, alabandite, arsenopyrite, barite, cinnabar, fluorapatite, orpiment, pyrite, realgar, routhierite, sphalerite, tilasite, titanite, etc. The new mineral is non-fluorescent, black, opaque with a metallic lustre and black streak. It is brittle with an uneven fracture and no obvious parting and cleavage. Its Vickers hardness (VHN10) is 144 kg/mm2 (range 131–167) and its calculated density is 5.450 g cm-3. In reflected light tsygankoite is white; between crossed polars it is dark-grey to black. It is strongly anisotropic: rotation tints vary from light-grey to dark-grey to black. Pleochroism and internal reflections are not observed. The chemical composition of tsygankoite (wt.%, electron-microprobe data) is: Mn 6.29, Fe 0.02, Cu 0.02, Ag 0.01, Hg 5.42, Tl 26.05, Pb 5.84, As 3.39, Sb 30.89, S 21.87, Se 0.01, total 99.81. The empirical formula, calculated on the basis of 90 atoms pfu, is: Mn8.06Tl8.00(Hg1.90Fe0.03Cu0.02Ag0.01)Σ1.96(Sb17.85As3.18Pb1.98Tl0.97)Σ23.98(S48.00Se0.01)Σ48.01. Tsygankoite is monoclinic, space group C2/m, a = 21.362(4) Å, b = 3.8579(10) Å, c = 27.135(4) Å, β= 106.944(14)°, V = 2139.19(17) Å3 and Z = 1. The five strongest diffraction peaks from X-ray powder pattern [listed as (d,Å(I)(hkl)] are: 3.587(100)(112), 3.353(70)(-114), 3.204(88)(405), 2.841(72)(-513) and 2.786(99)(-514). The crystal structure of tsygankoite was refined from single-crystal X-ray diffraction data to R = 0.0607 and consists of an alternation of two thick layer-like arrays, one based on PbS-archetype and second – on SnS-archetype. Tsygankoite has been approved by the IMA-CNMNC under the number 2017-088. It is named for Mikhail V. Tsyganko, mineral collector from Northern Urals, who collected the samples where the new mineral was discovered.

Gigantic particle accelerators, incredibly complex detectors, an antimatter factory and the discovery of the Higgs boson – this is part of what makes CERN famous. Only a few know that CERN also hosts the world largest Open Access initiative: SCOAP3. The Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP3) started operation in 2014 and has since supported the publication of 19,000 Open Access articles in the field of particle physics, at no direct cost, nor burden, for individual authors worldwide. SCOAP3 is made possible by a 3,000-institute strong partnership, where libraries re-direct funds previously used for subscriptions to ’flip’ articles to ’gold Open Access’. With its recent expansion, the initiative now covers about 90% of the journal literature of the field. This article describes the economic principles of SCOAP3, the collaborative approach of the partnership, and finally summarizes financial results after four years of successful operation.

Chemical and physical properties of nanoparticles (NPs) are strongly influenced not only by the crystal structure of the respective material including crystal structure defects, but also by the NP size and shape. Contemporary transmission electron microscopy (TEM) is capable of describing all of these NP characteristics, however typically with a different statistical relevance. While the size and shape of NPs are frequently determined on a large ensemble of NPs and thus with good statistics, the characteristics on the atomic scale are usually quantified for a small number of individual NPs and thus with a low statistical relevance. In this contribution, we present a TEM-based characterization technique, which is capable of determining relevant characteristics of NPs in a scale-bridging way – from the crystal structure and crystal structure defects up to the NP size and morphology – with a sufficient statistical relevance. This technique is based on a correlative multi-scale TEM approach that combines information on atomic scale obtained from the high-resolution imaging with the results of the low-resolution imaging assisted by a semi-automatic segmentation routine. The capability of the technique is illustrated on several examples including Au NPs having different shape, Au nanorods having different facet configurations and multi-core iron oxide nanoparticles having a hierarchical structure.

Dual-fraction proteomics reveals a novel class of proteins impacted by nanoparticle exposure. Background: Nanoparticles (NPs) interact with cellular proteomes, altering biological processes. Understanding these interactions requires comprehensive analyses beyond solely characterizing the NP corona. Methods: We utilized a dual-fraction mass spectrometry (MS) approach analyzing both NP-bound and unbound proteins in Saccharomyces cerevisiae sp. protein extracts exposed to silica nanoparticles (SiNPs). We identified unique protein signatures for each fraction and quantified protein abundance changes using spectral counts. Results: Strong correlations were observed between protein profiles in each fraction and non-exposed controls, while minimal correlation existed between the fractions themselves. Linear models demonstrated equal contributions from both fractions in predicting control sample abundance. Combining both fractions revealed a larger proteomic response to SiNP exposure compared to single-fraction analysis. We identified 302/56 proteins bound/unbound to SiNPs and an additional 196 "impacted" proteins demonstrably affected by SiNPs. Conclusion: This dual-fraction MS approach provides a more comprehensive understanding of nanoparticle interactions with cellular proteomes. It reveals a novel class of "impacted" proteins, potentially undergoing conformational changes or aggregation due to NP exposure. Further research is needed to elucidate their biological functions and the mechanisms underlying their impact.

In this paper we derived an expression that allows the determination of the thermo-optic coefficient of weakly-guiding germanium-doped silica fibers, based on the thermal behavior of optical fiber devices, such as, fiber Bragg gratings (FBGs). The calculations rely on the full knowledge of the fiber parameters and on the temperature sensitivity of FBGs. In order to validate the results, we estimated the thermo-optic coefficient of bulk GeO2 glass at 293 K and 1.55 m to be 18.3x10-6 K-1. The determination of this value required to calculate a correction factor which is based on the knowledge of the thermal expansion coefficient of the fiber core, the Pockels’ coefficients (p11=0.125, p12=0.258 and p44=-0.0662) and the Poisson ratio (=0.161) of the SMF-28 fiber. To achieve that goal, we estimated the temperature dependence of the thermal expansion coefficient of GeO2 and we discussed the dispersion and temperature dependence of Pockels’ coefficients. We have presented expressions for the dependence of the longitudinal and transverse acoustic velocities on the GeO2 concentration used to calculate the Poisson ratio. We have also discussed the dispersion of the photoelastic constant. An estimate for the temperature dependence of the thermo-optic coefficient of bulk GeO2 glass is presented for the 200-300 K temperature range.

Layered Ti3C2Tx MXene has been successfully intercalated and exfoliated with the simultaneous generation of a 3D silica network by treating its cationic surfactant intercalation compound (MXene-CTAB) with an alkoxysilane (TMOS) resulting in a MXene-silica nanoarchitecture that exhibits porosity along with the intrinsic properties of MXene (e.g., photothermal response). The ability of these new materials to produce thermal activation reactions of compounds previously adsorbed on MXene-SiO2 is shown here. For this purpose, the pinacol rearrangement reaction has been selected as a first model example, testing the effectiveness of NIR laser-assisted photothermal irradiation in these processes. This work shows that Ti3C2Tx – based nanoarchitectures open new avenues for applications that rely on the combined properties inherent to their integrated nanocomponents that could be extended to the broader MXene family.

Mesoporous silica nanoparticles (MSNs) can be used as carrier materials for the controlled release of pesticides while reducing their negative environmental impact. In this study, we screened an active ingredient, p-cymene (PC), with an excellent inhibitory effect on rice bacterial blight. Subsequently, the PC was successfully loaded onto MSNs via physisorption(PC@MSNs). PC@MSNs, characterized by a regular spherical shape, smooth surface, and an MSN average size of 262.9 nm, achieved an 8.6 % drug loading capacity. The release kinetics of the PC from the PC@MSNs demonstrated a sustained release (288 h) pattern influenced by drug diffusion. The efficacy of the PC@MSNs against Xanthomonas oryzae pv. Oryzae paralleled those of PC. Acute toxicity assays re-vealed that the PC@MSNs were less toxic to aquatic life (LC50=257.867 mg/L) and that the formu-lation showed no adverse effects on rice seedling growth. In summary, these results suggest that PC@MSNs can broaden PC's application scope in managing rice diseases.

Due to growing concerns about environmental pollution from plastic waste, plastic recycling research is gaining momentum. Traditional methods, such as incorporating inorganic particles, increasing cross-linking density with peroxides, and blending with silicone monomers, often improve mechanical properties but reduce flexibility for specific performance requirements. This study focuses on synthesizing silica nanoparticles with vinyl functional groups and evaluating their mechanical performance when used in recycled plastics. Silica precursors, namely sodium silicate, and vinyltrimethoxysilane (VTMS), combined with a surfactant, were employed to create pores, increasing silica's surface area. Early-stage introduction of vinyl functional groups prevented the typical post-synthesis reduction in surface area. Porous silica was produced in varying quantities of VTMS, and the synthesized porous silica nanomaterials were incorporated into recycled Polyethylene to induce cross-linking. Despite a decrease in surface area with increasing VTMS content, a significant surface area of 883 m2/g was achieved. In conclusion, porous silica with the right amount of vinyl content exhibited improved mechanical performance, including increased tensile strength, compared to conventional porous silica. This study shows that synthesized porous silica with integrated vinyl functional groups effectively enhances the performance of recycled plastics.

The present study concerns the application of electrochemical chloride extraction to concrete designed with partial replacements of Ordinary Portland Cement (OPC) from different binders, namely ground granulated blast furnace (GGBS), pulverized fly ash (PFA) and Silica Fume (SF), to attend the need of corrosion repair for modern constructions. Electrochemical Chloride Extraction (ECE) was applied to the specimens at a current density of 2A/m2 for 4 weeks. The chloride types and binding mechanisms appeared to have important implications on the different performance of treatment perceived for all binders. Considering total chlorides, removal was more significant for OPC and GGBS when compared to others. The main difference noted was that for GGBS the removal of bound chlorides was more significant due to a possible release of adsorbed chlorides from the silicate hydrates, present at higher intensities in this case. However, even though GGBS had greater rates of bound chloride removal it had still the same percentage as OPC for total efficiency due to the fact that in OPC the removal of free chlorides is more expressive.

Reinforcement corrosion due to chloride attack is of major economic significance for reinforced concrete structures. Pozzolans are known to inhibit corrosion initiation mainly by reducing concrete permeability. However, there is evidence in the literature that changes in the chemical environment in the concrete due to the pozzolans may be creating improved corrosion resistance, by themselves. In this study, the composition of a pore solution of mature hydrated cement paste containing silica-fume at different ratios was analyzed. The electrochemical behavior of reinforcing steel was studied in simulated pore solutions with silicate concentrations ranging from 0 to 35.6 mM, which are within the concentration range found by pore solution extraction to be up to 49 mM. Polished reinforcing steel specimens were used for cyclic voltammetry in simulated pore solutions with chloride concentrations of 10-20%. Better corrosion protection was found with increasing silicate concentration up to 3.56 mM. This was indicated by lower corrosion currents both in the passive state and after anodic activation. Anodic activation of steel in a 35.6 mM silicate solution with 20% NaCl yielded a higher potential than the anterior potential.

The silanol activity and trace metal detection methods for chemically bonded silica gels were evaluated in silico. Test compounds with large molecular sizes may demonstrate negative results because of the possibility of indirect hydrogen bonding via short alkyl groups or siloxane of the silica gels. This hypothesis was based on the observation of weak hydrogen bonding energy values similar to those observed in the study of the alkyl group effect on the hydrogen bonding of alkanols. Consequently, smaller molecules may be a better choice for the analysis of bonded-phase quality.

This work describes the preparation of mesoporous silica by the green reaction of rice husk ash (RHA) with glycerol, followed by the modification and the potential use as a drug carrier. The reaction was carried out at 215 °C for 2 h. The solution was further hydrolyzed with deionized water and aged for various times (24, 48, 120, 360, 528 and 672 h) before calcinations at 500 oC for 24 h. Further treatment of prepared mesoporous silica was performed using trimethylmethoxysilane (TMMS) to obtain hydrophobic Mesoporous silica. For all synthesized silica, silica contents were as high as 95%wt, whereas organic residues were less than 3%wt. RHA-glycerol showed the highest specific surface area with smallest pore diameter (205.70 m2/g, 7.46 nm) when aged for 48 h. The optimal hydrolysis-ageing period of 120 h resulted in 500.7 m2/g BET surface area, 0.655 cm3/g pore volume and 5.23 nm pore diameter. The surface modification of RHA-glycerol was succeeded through the reaction with TMMS as confirmed by FTIR. Ibuprofen was selected as a model drug for the adsorption experiments. The adsorption under supercritical CO2 was carried out at isothermal temperature of 40 ˚C and 100 bar, % ibuprofen loading of TMMS modified mesoporous silica (TMMS-g-MS) was 6 times less than mesoporous silica aged for 24 h (MS-24h) due to the hydrophobic nature of modified mesoporous silica, not surface and pore characteristics. The release kinetics of ibuprofen-loaded mesoporous silicas were also investigated in vitro. The release rate of ibuprofen-loaded MS-24h was much faster than that of ibuprofen-loaded TMMS-g-MS, but comparable to the crystalline ibuprofen. The slower release rate was attributed to the diffusion control and the stability of hydrophobic nature of modified silica. This would allow the design for the controlled release drug delivery system.

Some peptide-based drugs including oxytocin, vasopressin, ziconotide, pramlintide, nesiritide, and octreotide, contain one intramolecular disulfide bonds. A novel and reusable monodispersed silica nanosphere-supported Pt(IV) complex (SiO2@TPEA@Pt(IV)) was synthesized via a four-step procedure and used for formation of intramolecular disulfide bonds in peptides. TEM and chemical mapping results for the Pt(II) intermediates and for SiO2@TPEA@Pt(IV) show that the silica nanospheres possess a monodisperse spherical structure and contain uniformly distributed Si, O, C, N, Cl, and Pt. The valence state of Pt on the silica nanospheres was characterized by XPS. The Pt(IV) loaded on SiO2@TPEA@Pt(IV) was 0.15 mmol/g, as determined by UV-vis spectrometry. Formation of intramolecular disulfides in six dithiol-containing peptides of variable lengths by use of SiO2@TPEA@Pt(IV) was investigated and the relative oxidation yields were determined by HPLC. In addition, peptide 1 (Ac-CPFC-NH2) was utilized to study the reusability of SiO2@TPEA@Pt(IV). No significant decrease in the relative oxidation yield was observed after ten reaction cycles. Moreover, the structure of SiO2@TPEA@Pt(IV) after being used ten cycles was determined to be similar to its initial one, demonstrating the cycling stability of the complex.

The goal of this study is to synthesize, determine the structure, and examine the antimicrobial properties of novel metal complexes of 2,4-dithiouracil and its derivatives. These complexes were obtained by mixing aqueous solutions of the corresponding metal salts with the ligand dissolved in DMSO and aqueous NaOH, using a metal-to-ligand ratio of 1:4:2. The structures of the new compounds were analyzed by melting point determination, microwave plasma atomic emission spectrometry (MP-AES) for Cu and Au, inductively coupled plasma optical emission spectrometry (ICP-OES) for S, ATR, solution and solid-state NMR and Raman spectroscopy. The interpretation of the complex spectra was aided by data for 2,4-dithiouracil obtained from 1H-1H COSY, DEPT-135, HMBC, and HMQC spectra. Additionally, the antimicrobial activity of these complex-es and the free ligands was evaluated against Gram-positive and Gram-negative bacteria, as well as yeasts.

Electronic waste (e-waste), characterized by the widespread disposal of electronic devices, shows a growing environmental challenge. In this study, we explore the electrocatalytic potential of gold nanoparticles supported on Vulcan obtained from e-waste for their application as electrocatalysts for the methanol oxidation reaction in alkaline media. Gold nanoparticles are synthesized from gold coatings recovered from Intel Pentium 4 processor pins, highlighting their sustainability as electrocatalyst precursors. Comprehensive characterization, including UV-Vis spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray dif-fraction, is performed to assess the electrocatalyst's structural properties. Electrochemical evalu-ation is carried out in 0.5 M KOH electrolyte employing the rotating disk electrode technique, us-ing cyclic voltammetry for the study of methanol oxidation. Remarkably, the gold nanoparticles show electrocatalytic activity on par with commercially synthesized counterparts, demonstrating the feasibility of this approach for sustainable electrocatalyst production. Thus, this research opens new routes for utilizing e-waste as a source of valuable catalyst materials, addressing en-vironmental and technological challenges in the field of alkaline fuel cells.

In this work, a colorimetric indicator based on gold nanoparticles (AuNP) and a biodegradable and eco-friendly polymer (sodium alginate, Alg.), has been developed, for the real-time detection of fish spoilage products. AuNP and colorimetric indicator were characterized by: UV-Vis, FTIR spectroscopies, TGA, DSC, XRD, TEM, and colorimetry. The UV-Vis spectrum and TEM showed the successful synthesis, the spherical shape, and the size of AuNPs. Results indicated color changes of the indicator in packaged fish on day 9 of storage at refrigerated temperature (5ºC). These results showed the successful application of colorimetric indicator in the detection of TVB-N in packaged fish.

This study investigates the relationship between energy metals and precious metals to assess their suitability as safe haven assets in clean energy investment portfolios. It focuses on the impact of events in 2020 and 2022, characterized by substantial investments in clean energy. The research reveals that, except for Nickel Futures (NICKELc1), energy metals are positively linked with clean energy indexes. This suggests that they can serve as a secure investment option for green investors looking to diversify their portfolios. As a result, the study dismisses the initial question, indicating that energy metals can indeed be considered safe havens within the context of clean energy investments. Additionally, the research reinforces prior findings that precious metals like gold, silver, and platinum possess safe haven characteristics in relation to specific clean energy stock indexes. These results have significant implications, particularly given the increasing investments in clean energy stocks and the recurring uncertainties in the market. In summary, this study supports the idea that both energy metals and precious metals can play valuable roles in clean energy portfolios, providing stability during turbulent times in the market.

Cervical cancer is the most common female reproductive tract tumor and is currently the only cancer that can be prevented by vaccination. Early detection and treatment of cervical cancer can be achieved through regular screening for human papillomavirus (HPV). Therefore, in this paper, an electrochemical sensor was designed to detect HPV 16 using a dual signal amplification technique. APTES modified glassy carbon electrode to improve stability. Combining gold nanoparticles and chain amplification reactions for signal amplification purposes. The limit of detection (LOD) was 1.731×10-16 mol/L, and the detection range of this electrochemical sensor was increased in comparison to previous research, with a linear response range from 1.0×10-13 mol/L to 1.0×10-5 mol/L (R2 = 0.99232) for the target detector.In addition, the sensor showed equally good recovery in sophisticated human serum samples. It shows that it has good interference resistance and the designed biosensor can be a powerful and reliable tool for clinical disease diagnosis.

Treatment of the [AuCl(tetrahydrothiophene)] complex with 4-chloro-2-iodo-1-isocyanobenzene furnished the gold(I) compound [AuCl(CNC6H3-4-Cl-2-I)] (1). In the crystal structure of 1, the linear C–Au–Cl group is subject to the solid-state head-to-tail pairing which is determined by the aurophilic Au···Au and the rare π-holeCN···Cl interactions. These two types of structure-determining interactions are complementary to each other and the system of Au···Au and CCN···Cl contacts accomplishes 2D extended ladder-type architecture. In addition, the terminal I-atoms are involved in the three-center halogen bonding. Density functional theory calculations, employing a set of computational tools, verified the role of Au···Au and π-holeCN···Cl noncovalent bonds in the spectrum of noncovalent forces.

It is well-known that the peroxidase enzyme catalyzes the oxidation of different substrates such as 3,3’,5,5’-thetramethylbenzidine, and 3,3’-diaminobenzidine, however, the affinity of different substrates to the enzyme and consequently and catalytic performances of the enzyme toward different substrates is not same, resulting in different kinetics indexes. As the BSA-gold nanozymes are considered artificial peroxidase enzymes, hence, the kinetics indexes of these nanozymes should also be varied by varying their substrate. Hence, in this work, a comparative study was performed on the kinetics performances of BSA-gold nanozymes for enzyme-mediated oxidations of 3,3’,5,5’-thetramethylbenzidine, and 3,3’-diaminobenzidine. The results showed that the Km value of BSA-gold nanozymes was 0.03 mM and 0.72 mM toward TMB and DAB, in order, to reveal the higher affinity (lower Km) of TMB for binding to nanozyme active nodes compared to its alternative substrate, DAB. In contrast, the Vmax was found to be 263 nM sec^-1 and 185 nM sec^-1 for nanozmye-mediated oxidation of TMB and DAB, respectively. The higher Vmax of the nanozyme-mediated oxidation of TMB revealed that the catalytic efficiency of BSA-Au nanozymes toward TMB oxidation is higher (about 1.5-fold) than that of the DAB oxidation. The difference between the kinetic indexes of TMB and DAB may be related to their different oxidation pathways and their different reactivity. In fact, the DAB oxidizes via an n-electron irreversible oxidation pathway to produce an indamine polymer. While TMB nanozyme-mediated oxidation has occurred upon a 2-electron reversible mechanism for the production of a cation radical. These different pathways resulted in different kinetic performances.

The ionic liquid A327H+Cl- is generated by reaction of the tertiary amine A327 (industrial mixture of tri-octil and tri-decyl amines) and hydrochloric acid solutions. Further, the extraction of Au(III) by A327H+Cl- ionic liquid under various variables, including metal and ionic liquid concentrations, has been investigated. Results indicate that A327H+AuCl4- is formed, by an exothermic (ΔHº= -3 kJ/mol) reaction, in the organic solution. Aqueous ionic strength influences the formation constants values and the specific interaction theory (SIT) is used to estimate the interaction coefficient between AuCl4- and H+. Gold (III) is stripped using thiocyanate media, and from the strip solutions, gold is precipitated as gold nanoparticles.

By the use of the tertiary amine A327 and 1 M HCl solution as precursors, the ionic liquid A327H+Cl- was generated and used to investigate its performance in the transport of Au(III) form hydrochloric acid medium. The influence of the stirring speed (600-1800 min-1), ionic liquid concentration (1.25-50% v/v) in the membrane phase and gold concentration (0.01-0.15 g/L) in the feed phase on metal transport have been investigated. An equation which included both equilibrium and kinetics parameters was derived, and the membrane diffusional resistance (Δm) and feed phase diffusional resistance (Δf) was estimated as 9.5x106 s/cm and 307 s/cm, respectively. At carrier concentrations in the 5-50% v/v range and gold concentrations in the 0.01-0.15 g/L range, metal transport is controlled by diffusion of metal species through the feed boundary layer, whereas at the lowest carrier concentrations, membrane diffusion is predominant. From the receiving solutions, gold can be recovered as gold nanoparticles.

It has been suggested that particle size plays an important role in determining the genotoxicity of gold nanoparticles (GNPs). The purpose of this study was to compare the potential radio-sensitization effects of two different sized GNPs (3.9 and 37.4 nm) fabricated and examined in vitro in Lewis Lung carcinoma (LLC) as a model of non-small cell lung cancer through use of comet and clonogenic assays. After the treatment of 2Gy X-ray irradiation, both particle sizes demonstrated increased DNA damage when compared to treatment with particles only and radiation alone. This radio-sensitization was further translated into a reduction in cell survival demonstrated by clonogenicity. This work indicates that GNPs of both sizes induce DNA damage in LLC cells at the tested concentrations, whereas the 37.4 nm particle size treatment group demonstrated greater significance in vitro. The presented data aids in the evaluation of the radiobiological response of Lewis Lung carcinoma cells treated with gold nanoparticles.

Galectin-3 is considered a cancer biomarker and bioindicator of fibrosis and cardiac remodeling, and, therefore, it is desirable to develop convenient methods for its detection. Herein, an approach based on the development of multivalent electrochemical probes with high galectin-3 sensing abilities is reported. The probes consist of multivalent presentations of lactose–ferrocene conjugates scaffolded on poly(amido amine) (PAMAM) dendrimers and gold nanoparticles. Such multivalent lactose–ferrocene conjugates are synthesized by coupling of azidomethylferrocene-lactose building blocks on alkyne-functionalized PAMAM, for the case of the glycodendrimers, and to disulfide‐functionalized linkers that are then used for the surface modification of citrate-stabilized gold nanoparticles. The binding and sensing abilities towards galectin 3 of both ferrocene-containing lactose dendrimers and gold nanoparticles have been evaluated by means of isothermal titration calorimetry, UV-vis spectroscopy, and differential pulse voltammetry. The highest sensitivity by electrochemical methods to galectin-3 was shown by lactosylferrocenylated gold nanoparticles, which are able to detect the lectin in nanomolar concentrations.

In the present study, we have followed the hydrothermal path for the synthesis of gold nanoparticles (Au NPs) from the biomaterial Elaeocarpus ganitrus seeds extract, which is a rapid, eco-friendly, non-chemical way. The prepared NPs were thoroughly analyzed by PXRD & HR-TEM studies and also tested for photocatalytic dye degradation and anticancer studies. Besides, antioxidant, antibacterial and anticancer properties of Au NPs were studied. In vitro studies revealed the dose-dependent cytotoxic effect of Au NPs. The prepared nanoparticles showed good cytotoxic impact against Prostate cancer (PC-3) cells line. The results of the present study could contribute to synthesize new and cost-effective drugs from Elaeocarpus ganitrus seeds extract by using bio approach.

The Sol Hamed (SH) area is a part of the Arabian-Nubian Shield (ANS) ophiolites occurred within Onib-Sol Hamed suture zone in the southern Eastern Desert of Egypt. The ophiolitic assemblages in this area are represented by serpentinite, metagabbro and arc assemblages represented by metavolcanics. They later intruded by gabbroes and granites. Geochemically, the compatible trace elements (Cr=2426–2709 ppm, Ni=1657–2377 ppm and Co=117–167 ppm) enrichment in SH serpentinites indicate derivation from a depleted mantle peridotite source. They show affinity to the typical metamorphic peridotites. The normative compositions reflect harzburgitic mantle source. Their Al2O3 contents (0.05–1.02 wt. %) are akin to oceanic and active margin peridotites and Pan-African serpentinites. The Cr and TiO2 contents indicate supra-subduction zone (SSZ) environment. Their Al2O3/SiO2 and MgO/SiO2 ratios support the SSZ affinity and are similar to ANS peridotites with fore-arc setting. Moreover, their Al2O3 and CaO depletion is typical of fore-arc peridotites. Structurally, the area represents four deformational events can be well-known in the Neoproterozoic rocks (D1, D2, D3 and D4); D1: E–W thrust faults and related E–W (F1) folds; D2: NW–SE thrust faults and related NW–SE (F2) folds were formed; D3: conjugate NNW-trending sinistral and NNE-trending dextral transpression, as well as N–trending tight folds (F3) and D4: is E–W dextral strike-slip and dip-slip normal faults striking NNW–SSE to N–S and E–W may be related to Red Sea rifting. There are major three fault sets affected the area. The first set trend mainly NE-SW and is manifested in the volcanic-sedimentary assemblage and Gabal SH and have important role in mineralization. The second set trend E-W affecting all the basement rocks and disturbs the first fault set. The third set trend N-S affected all the rock units. Magnesite mineralization in SH serpentinites is cryptocrystalline formed due to hydrothermal alteration of the serpentinite host rocks. It is occur as snow-white veins and stock-works. These characteristics are typical of Kraubath type magnesite deposits. Gold mineralization is confined to malachite-bearing quartz veins, smoky quartz veins and alteration zones. Malachite-bearing quartz veins trending NW-SE cut through gabbroic rocks and exhibit mylonitic structure. They are fractured containing malachite and disseminated sulfide minerals. Smoky quartz veins trending NE-SW with SE steeply dipping intrude the meta-andesite. They are intensively sheared containing iron oxides in the fissures. The gold grades increase with arsenopyrite occurrences. On the other hand, the barren quartz veins are nearly vertical with E-W directions. Alteration zones with NW-SE trend and nearly vertical dip intrude metagabbros and metavolcanics. Hematite, limonite, goethite and fresh pyrite characterize these zones. They occur mainly neighboring the auriferous quartz veins.

Gold clusters protected by 3-MBA ligands (MBA = mercaptobenzoic acid, -SPhCO2H) have attracted recent interest for their unusual structures and advantageous ligand-exchange and bioconjugation properties. Azubel et al. first determined the core structure of an Au68-complex, which was estimated to have 32 ligands (3-MBA groups). To explain the exceptional structure-composition and reaction properties of this complex, and its larger homologs, Tero et al. proposed a “dynamic stabilization” via carboxyl O-H--Au interactions. Herein, we report the first results of an integrated LC/MS analysis of unfractionated samples of gold / 3-MBA clusters, spanning the narrow size range 13.4 to 18.1 kDa. Using high-throughput procedures adapted from bio-macromolecule analyses, we show that integrated capillary HPLC-ESI-MS, based upon aqueous-methanol mobile phases and ion-pairing reverse-phase chromatography, can separate several major components from the nanoclusters mixture that may be difficult to resolve by standard native gel electrophoresis due to their similar size and charge. For each component, one obtains a well-resolved mass spectrum, nearly free of adducts or signs of fragmentation. A consistent set of molecular mass determinations is calculated from detected charge-states tunable from 3- (or lower), to 2+ (or higher). One thus arrives at a series of new compositions (n, p) specific to the Au/3-MBA system. The smallest major component is assigned to the previously unknown (48, 26); the largest one is evidently (67, 30), vs. the anticipated (68, 32). Various explanations for this discrepancy are considered. A prospective is given for the several members of this novel series, along with a summary of the advantages and present limitations of the micro-scale integrated LC/MS approach to characterize such metallic-core macro-molecules, and their derivatives.

Redox reactions are of great importance in environmental catalysis. Gold nanoparticles (NPs) have attracted much attention because of their catalytic activity and their localized surface plasmon resonance (LSPR). In the present study, we investigated in details the reduction of ferricyanide (III) ion into ferrocyanide (II) ion catalyzed by spherical gold nanoparticles of two different sizes 15 nm and 30 nm and excited at their LSPR band. Experiments were conducted in the presence (or not) of sodium thiosulfate. This catalysis is enhanced in the presence of Au-NPs under visible light excitation. This reduction takes also place even without sodium thiosulfate. Our results demonstrate the implication of hot electrons in this reduction.

Up-conversion nanoparticles (UCNP) under near-infrared (NIR) light irradiation have been well investigated in the field of bio-imaging. However, the low up-conversion luminescence (UCL) intensity limits applications. Plasmatic modulation has been proposed as an effective tool to adjust the luminescence intensity and lifetime. In this study discrete dipole approximation (DDA) was explored concerning guiding the design of UCNP@mSiO2-Au structures with enhanced UCL intensity. The extinction effects of gold shells could be changed by adjusting the distance between the UCNPs and the Au NPs by synthesized tunable mesoporous silica (mSiO2) spacers. Enhanced UCL was obtained under 808 nm irradiation. Theoretical predictions could not be demonstrated to full extend by experimental data, indicating that better models for simulation need to better take into account inhomogeneities in particle morphologies.

The value of QuantiFERON in the diagnosis of tuberculosis and in the monitoring of the response to anti-tuberculosis treatment is unclear. The aims of this study were to evaluate the accuracy of the QuantiFERON-TB Gold In-Tube (QFT-GIT) test in the diagnosis of tuberculosis and in the monitoring of the response to anti-tuberculosis treatment in patients with active pulmonary tuberculosis (PTB). Between January 2013 and December 2015, 128 cases with active PTB and 128 controls with no mycobacterial infection, matched by age (within 3 years) and by the week that they visited Tainan Chest Hospital, were enrolled in the study. Serial testing by QFT-GIT at baseline and after 2 and 6 months of treatment was performed. At these time points, a comparison of the performance of QFT-GIT with that of sputum culture status among study subjects was conducted. Compared to baseline, 116 (87.2%) cases showed a decreased response, whereas 17 (12.8%) showed persistent or stronger interferon-gamma (IFN-γ) responses at 2 months. Their IFN-γ responses declined significantly from baseline to 2 months (median, 6.32 vs. 4.12; P < 0.005). The sensitivity values of the QFT-GIT test for the detection of pulmonary tuberculosis at cut-off points of 0.35 IU/ml, 0.20 IU/ml, and 0.10 IU/ml were 74.4%, 78.2%, and 80.5%, respectively. The specificity values at cut-off points of 0.35 IU/ml, 0.20 IU/ml, and 0.10 IU/ml were 66.2%, 63.9%, and 57.1%, respectively. Our results support the QFT-GIT assay as a potential tool for diagnosing tuberculosis and for monitoring the efficacy of anti-tuberculosis treatment.

Micro lens arrays (MLAs) play a critical role in optical imaging, new energy technologies, and advanced displays. In this work, high-quality micro lens arrays with controllable profiles using femtosecond-laser-induced modification assisted wet etching (FLIM-WE) were fabricated. The effects of laser single-pulse energy, pulse number, and hydrofluoric acid etching duration on micro lens profiles were systematically studied. Optimization of these parameters enabled the successful preparation of dimensionally controlled micro lens arrays with stable performance and excellent surface quality on fused silica substrates. Ultimately, two types of micro lens arrays were fabricated using femtosecond laser-assisted wet etching. These arrays demonstrated exceptional uniformity and surface quality (Ra~100nm), facilitating clear imaging at various magnifications, with an adjustment range of 1.3X~3.0X. This provides a potential technical support for special micro-optical systems.

Nanocomposite hydrogels offer remarkable potential for applications in bone tissue engineering. They are synthesized through the chemical or physical crosslinking of polymers and nanomaterials, allowing for the enhancement of their behaviour by modifying the properties and compositions of the nanomaterials involved. However, their mechanical properties require further enhancement to meet the demands of bone tissue engineering. Here, we present an approach to improve the mechanical properties of nanocomposite hydrogels by incorporating polymer grafted silica nanoparticles into a double network inspired hydrogel (gSNP Gels). The gSNP Gels were synthesised via a graft polymerization process using a redox initiator. gSNP Gels were formed by grafting 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as the first network gel followed by a sequential second network acrylamide (AAm) onto amine functionalized silica nanoparticles (ASNPs). We utilized glucose oxidase (GOx), to create an oxygen-free atmosphere during polymerization resulting in higher polymer conversion compared to argon degassing. The gSNP Gels showed excellent compressive strengths of 13.9 ± 5.5 MPa, a strain of 69.6 ± 6.4%, and a water content of 63.4% ± 1.8. The synthesis technique demonstrates a promising approach to enhance the mechanical properties of hydrogels, which can have significant implications for bone tissue engineering and other soft tissue applications.

Insects quickly develop resistance to conventional chemical insecticides. The use of silica nanoparticles (SiO₂NPs) is a promising new approach for managing insect pests. The insects that have been studied are, in most cases, external feeders and internal leaf feeders have not been well studied. Here, we investigate the efficiency of SiO₂NPs in controlling the American serpentine leafminer Liriomyza trifolii (Diptera: Agromyzidae), a devastating insect pest of a wide range of crops. SiO₂NPs at concentrations of 50, 100, 200 and 400 mg/L compared to a control of distilled water were applied to intact Phaseolus vulgaris leaves by spraying to evaluate their effects, via the plant, on the number, survival, developmental/feeding speed, body mass/size and sex ratio of L. trifolii released after spraying. A qRT-PCR analysis was conducted to assess oxidative stress in L. trifolii based on the gene expression level of the two major antioxidant enzymes; catalase and superoxide dismutase. The number of mines, survival rate and puparia weight were lower than the control at the highest concentration of SiO₂NPs, while pupariation was delayed at most of the concentrations studied and puparium weight/size decreased at low concentrations. Sex ratio was not affected by SiO₂NPs. Gene expression levels of the antioxidant enzymes at the pupal stage were not significantly affected by SiO₂NPs at any concentration but some individuals showed up-regulation at low SiO₂NP concentrations, inferring development of resistance. This study demonstrated that a priori application of the highest concentration of SiO₂NPs to plants effectively reduces a leafminer population but that application of even the lowest concentration can decrease the life history trait values of surviving leafminers.

This study's objective was to propose the use of textile braiding manufacturing methods, thus facilitating the application of the high precision and accurate measurability of optical fiber Bragg grating sensors to various structures. The purpose of this study was to Combine 3d braid processing with the optical Bragg grating sensor's accurate metrology. Out of limits of the sensor's epoxy attachment methods, the textile braiding method can make applicable scope diversify. The braiding processing is capable of designing a 3D fabric module processing, multiple objective mechanical fiber arrangement, and material characteristics. Optical stress-strain response conditions were explored through the optimization of design elements between the Bragg grating sensor and braiding. For this study, Bragg grating sensors were located 75% apart from the fiber center. The sensor core structure is helical of 1.54 pitch. A polyurethane synthetic yarn was braided together with the sensor on the Weaving machine core part in a braiding. Prototyping results, a negative Poisson's ratio makes curled the braided Bragg grating sensor. The number of polyurethane string yarns has been conducted the role of wrap angle in braiding. The 12 strands condition showed an increase in double stress-strain response rate at a Poisson ratio of 1.3%, and 16 strands condition was found to affect the sensor with noise at a Poisson ratio of 1.5%. This study can suggest applying braid processing of the Bragg grating sensor, which is expected to create and develop a new monitoring sensor.

This study's objective was to propose the use of textile braiding manufacturing methods, thus facilitating the application of the high precision and accurate measurability of optical fiber Bragg grating sensors to various structures.The purpose of this study was to Combine 3d braid processing with the optical Bragg grating sensor's accurate metrology. Out of limits of the sensor's epoxy attachment methods, the textile braiding method can make applicable scope diversify. The braiding processing is capable of designing a 3D fabric module processing, multiple objective mechanical fiber arrangement, and material characteristics. Optical stress-strain response conditions were explored through the optimization of design elements between the Bragg grating sensor and braiding. For this study, Bragg grating sensors were located 75% apart from the fiber center. The sensor core structure is helical of 1.54 pitch. A polyurethane synthetic yarn was braided together with the sensor on the Weaving machine core part in a braiding.Prototyping results, a negative Poisson's ratio makes curled the braided Bragg grating sensor. The number of polyurethan string yarns has been conducted the role of wrap angle in braiding. The 12 strands condition showed an increase in double stress-strain response rate at a Poisson ratio of 1.3%, and 16 strands condition was found to affect the sensor with noise at a Poisson ratio of 1.5%. This study can suggest applying braid processing of the Bragg grating sensor, which is expected to create and develop a new monitoring sensor.

The adsorption of carbon dioxide on amino silanes-functionalized MCM-41 and SBA-15 materials is reported. The functionalization of mesoporous silicas was made by post-synthesis method, by impregnation of 3-aminopropyltriethoxysilane. The obtained materials were characterized by X-ray diffraction, scanning and transmission electron microscopies, nitrogen adsorption-desorption and X-ray photoelectron spectroscopy measurements. The carbon dioxide adsorption capacities for the samples were carried out under ambient pressures. The obtained results evidenced that amino-silanes with a terminal amine (–NH₂) were functionalized through covalent coupling of this group on the surface of the channels in the ordered mesoporous silica, meaning that the amine is anchored on the surface of the bigger pores of the MCM-41 and SBA-15 support. For functionalized materials, the CO₂ adsorption capacity of the AMCM-41 increased from 0.18 to 1.1 mmol·g⁻¹, whereas for ASBA-15, it was from 0.6 to 1.8 mmol·g⁻¹. The Lagergren kinetic algorithms were applied in order to validate the obtained results, evidencing the enhanced carbon dioxide adsorption capacity and stability of the functionalized ordered mesoporous molecular sieves.

Alkali Silica Reaction (ASR) is known to be a serious problem for concrete worldwide, especially in high humidity and high temperature regions. ASR is a slow process that develops over years to decades and it is influenced by changes in environmental and loading conditions of the structure. The problem becomes even more complicated if one recognizes that other phenomena like creep and shrinkage are coupled with ASR. This results in synergistic mechanisms that can not be easily understood without a comprehensive computational model. In this paper, coupling between creep, shrinkage and ASR is modeled within the Lattice Discrete Particle Model (LDPM) framework. In order to achieve this, a multi-physics formulation is used to compute the evolution of temperature, humidity, cement hydration, and ASR in both space and time, which is then used within physics-based formulations of cracking, creep and shrinkage. The overall model is calibrated and validated on the basis of experimental data available in the literature. Results show that even during free expansions (zero macroscopic stress), a significant degree of coupling exists because ASR induced expansions are relaxed by meso-scale creep driven by self-equilibriated stresses at the meso-scale. This explains and highlights the importance of considering ASR and other time dependent aging and deterioration phenomena at an appropriate length scale in coupled modeling approaches.

Optical materials with a tunable localized surface plasmon resonance (LSPR) are of a great interest for applications in photonics and optoelectronics. In the present study we explored the potential of generating the LSPR band with an ultra-broad range of over 1000 nm in gold nanoparticles (NPs) precipitated through the thermal treatment in ZnO-Al2O3-SiO2 glass. Using the optical absorption spectroscopy, we demonstrated that the LSPR band's position and shape can be finely controlled by varying the thermal treatment route. Comprehensive methods including Raman spectroscopy, X-ray diffraction and high-resolution transmission electron microscopy were used to study the glass structure, while computational approaches were used for the theoretical description of the absorption spectra. Obtained results allowed us to suggest a scenario responsible for such abnormal LSPR band broadening which includes possible interparticle plasmonic coupling effect taking place during the liquid-liquid phase separation of the heat-treated glass. The formation of gold NPs with an ultra-broad LSPR band in glasses holds promise for sensitizing rare earth ion luminescence for new photonics devices.

This study aimed to develop multifunctional nanoplatforms for both cancer imaging and therapy using superparamagnetic iron oxide nanoparticles (SPIONs). Two distinct synthetic methods, reduction-precipitation (MR/P) and co-precipitation at controlled pH (MpH), were explored, including the assessment of coating’s influence, namely dextran and gold, on their magnetic properties. These SPIONs were further functionalized with gadolinium to act as dual T1/T2 contrast agents for magnetic resonance imaging (MRI). Parameters such as size, stability, morphology, and magnetic behavior were evaluated by a detailed characterization analysis. To assess their efficacy in imaging and therapy, relaxivity and hyperthermia experiments were performed, respectively. The results revealed that both synthetic methods lead to SPIONs with similar average, 9 nm. Mössbauer spectroscopy indicated that samples obtained from MR/P consist of approximately 11-13% of Fe present in magnetite, while samples obtained from MpH have higher content, of 33%-45%. Despite coating and functionalization, all samples exhibited superparamagnetic behavior at room temperature. Hyperthermia experiments showed increased SAR values with higher magnetic field intensity and frequency. Moreover, the relaxivity studies suggested potential dual T1/T2 contrast agent capabilities for the coated SPpH-Dx-Au-Gd sample, thus demonstrating its potential in cancer diagnosis.

Gold nanoparticles (AuNPs) exhibit improved optical and spectral properties compared to bulk materials, making them suitable for detection of DNA, RNA, antigens, and antibodies. Here, we describe a simple, selective, and rapid non-cross linking detection assay, using approx. 35 nm spherical Au nanoprobes, for a common mutation occurring in exon 19 of the epidermal growth factor receptor (EGFR), associated with non-small cell lung cancer cells. AuNPs were synthesized based on the seed-mediated growth method and functionalized with a specific 16 bp thiolated oligonucleotide using a pH-assisted method. Both AuNPs and Au nanoprobes proved to be highly stable and monodisperse by ultraviolet-visible spectrophotometry, dynamic light scattering (DLS) and electrophoretic light scattering (ELS). Our results indicate a detection limit of 1.5 µg mL−1 using a 0.15 nmol dm−3 Au nanoprobe concentration. In conclusion, this work is an effective possibility for a straight-forward, fast, and inexpensive alternative for the detection of DNA sequences related to lung cancer, leading to a potential platform for an early diagnosis of lung cancer patients.

Mozambique is one of the poorest countries of the world. However, it has natural resources and if they are managed under sustainable development principles, Mozambique can overcome the current problems. In the present socio-economic status, soil is one of its most important resources and must be protected from pollution and from degradation. This review focuses on the identification and discussion of the main soil quality stressors, namely: soil fertility; deforestation and its sources: agriculture, timber harvesting, charcoal production and uncontrolled fires; mining activities, manly gold artisanal explorations and industrial open-pit coal mining. The sustainable use of the natural resources is mandatory to allow future generations to continue profiting for this nature-based wealth.

Green synthesis using plant extracts has emerged as an eco-friendly, clean, and viable strategy alternative to chemical and physical approaches. The leaf, stem, and root extracts of Lannea discolor was utilized as a reducing and stabilizing agent in the synthesis of gold (AuNPs) and copper (CuNPs) nanoparticles. The formation of AuNPs and CuNPs confirmed by their color change, was characterised by UV–Vis Spectroscopy (UV- Vis), Scanning electron microscopy analysis and energy dispersive x-ray (SEM-EDX), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FTIR), coupled with minimum concentration inhibitory (MIC) antibacterial assays. AuNFs, NPs and CuNPs peaked at wavelengths in the ranges of 316, 544 and 564 nm respectively. TEM showed unexpected nanoflowers (30 – 97 nm) in the leaf extracts and spherical NPs (10 -33 nm; 9.3 – 37.5) from stem and root extracts, while spherical CuNPs (20 – 104 nm), were observed from all the extracts. EDX was able to confirm the presence of metal salts and FTIR revealed stable capping agents. AuNPs and NFs from L. discolor extracts showed appreciable antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Bacillus subtilis, when compared to the plant extracts, while none was observed from the CuNPs. These AuNPs and CuNPs are particularly appealing in a variety of applications in the biomedical as well as conductivity manufacturing, due to their shapes and sizes and economical and environmentally friendly production.

Rapid proliferation of traditional gold mining sites in Kédougou a Southeast region in Senegal, led to mass population migration from the neighboring West African countries and rapid expansion of small mining villages with poor hygiene and sanitation conditions. An outbreak of hepatitis E was reported in 2014 with several cases of febrile jaundice among traditional mine workers. In this study, we analyzed both HEV IgM and IgG seroprevalence and the associated risk factors of infection by testing any suspected case and contacts collected from February 2012 to November 2014. RNA-negative sera from suspected cases and contacts were tested for anti-HEV IgM and anti-HEV IgG. A total of 799 sera were collected from 290 suspected cases, 470 contacts and 39 individuals with missing information. The median age of the cohort study was 19 years (1-88 years) with a male/female sex-ratio of 1.9. We found an overall prevalence of 43.68% (332/760) of anti-HEV IgM and 38.15% (290/760) of anti-HEV IgG sera. Our data provide new insights into the HEV epidemiology and point to the crucial need to estimate the disease’s burden in Kédougou and assess the viral mechanisms driving the disease’s severity in pregnant women.

3D metal nanostructures are often the basis of several applications such as in catalysis, plasmonics, medical diagnosis, therapy, drug screening, ophthalmologic, and biomedical applications. Porous gold nanoparticles (PGNs) are intensively investigated due to their outstanding morphological as well as advantageous optical properties. Unfortunately, the thermal stability of these open-porous structures is poor, i.e. even as a result of low-temperature annealing (150$^\circ$C in air), their porosity disappears and they lose their favorable optical properties. In order to preserve their beneficial properties, a thin metal oxide coating can be applied. Changing the coating's thickness and/or composition, the optical response of the PGNs can also be tuned in a wide wavelength region. Moreover, these nanoparticles can be synthesized also in support-free form, which makes them more attractive from an application point of view. This review article summarizes some of the preparation modes of these complex nanostructures (fixed and support-free), as well as their thermal stability and optical responses.

The supramolecular aggregation processes occurring on metallic (aluminum and gold) surfaces in aqueous solutions of bovine serum albumin (BSA) during drying were studied using advanced scanning electron microscopy (SEM). The possible mechanism for the formation of amazing intricate fractal structures on metallic surfaces was proposed based on the analysis of SEM images, size distribution diagrams and EDX-scanning elements distribution maps.

The Koka gold deposit is located in the Elababu shear zone between the Nakfa terrane and the Adobha Abiy terrane, NW Eritrea. Based on the paragenetic study two main stages of gold mineralization were identified in the Koka gold deposit: 1) an early stage of pyrite-chalcopyrite-sphalerite-galena-gold-quartz vein; and 2) a second stage of pyrite-quartz veins. NaCl-aqueous inclusions, CO2-rich inclusions, and three-phase CO₂-H₂O inclusions occur in the quartz veins at Koka. The ore-bearing quartz veins formed at 268℃, from NaCl-CO₂-H₂O(-CH₄) fluids averaging 5 wt% NaCl eq. The ore-forming mechanisms include fluid immiscibility during stage I, and mixing with meteoric water during stage II. Oxygen, hydrogen and carbon isotopes suggest that the ore-forming fluids originated as mixtures of metamorphic water, meteoric water and magmatic water, whereas sulfur isotope suggest an igneous origin. Features of geology and ore-forming fluid at Koka deposit are similar to those of orogenic gold deposits, suggesting the Koka deposit might be an orogenic gold deposit related to granite.

In this work, an enzymatic sensor, based on a bionanocomposite film consisting of a polyelectrolyte complex (PEC) [Chitosan/kappa-carrageenan] doped with gold nanoparticles (AuNPs) encapsulating glucose oxidase (GOD) deposited on a gold electrode (Au) for glucose sensing, is described. Using the electrocatalytic synergy of AuNPs and GOD as a model of enzyme, the variation of the current (µA) as a function of the log of the glucose concentration (log [glucose]), shows 3 times higher sensitivity for the modified electrode (283.9) compared to that of the PEC/GOD modified electrode (93.7), with a detection limit of about 5 µM and a linearity range between 10µM and 7mM. The response of the PEC/AuNPs/GOD based biosensor also presents good reproducibility, stability and negligible interfering effects from ascorbic acid, uric acid, urea and creatinine. The applicability of the PEC/AuNPs/GOD based biosensor was tested in glucose-spiked saliva samples and acceptable recovery rates were obtained.

Plasmonic gold nanorods play important roles in nowadays state-of-the-art plasmonic sensing techniques. Most of the previous studies and applications focused on gold nanorods with relatively small aspect ratios, where the plasmon wavelengths are smaller than 900 nm. Gold nanorods with large aspect ratios are predicted to exhibit high refractive-index sensitivity (Langmir 2008, 24, 5233–5237.), which therefore should be promising for developing of high-performance plasmonic chemical- and bio-sensors. In this study, we developed gold nanorods with aspect ratios over 7.9, which exhibit plasmon resonances around 1064 nm. The refractive index (RI) sensitivity of these nanorods have been evaluated by varying their dielectric environment, whereby a sensitivity as high as 473 nm/RIU can be obtained. Furthermore, we have demonstrated the large-aspect-ratio nanorods as efficient substrate for surface enhanced Raman spectroscopy (SERS), where an enhancement factor (EF) as high as 9.47×10⁸ was measured using 4-methylbenzenethiol (4-MBT) as probe molecule. Finally, a type of flexible SERS substrate is developed by conjugating the gold nanorods with the polystyrene (PS) polymer. The results obtained in our study can benefit the development of plasmonic sensing techniques utilized in the near-infrared spectral region.

Although there are extensive literature reports on the use of gold nanoparticle (AuNP) based homogeneous assays for detection of biomolecules, very few experimental description and procedures involving their preparation are described. In this study, AuNPs conjugated to Bovine Serum Albumin or Envelope protein from Dengue II were developed as a homogeneous immunoassay for antibody detection. We report here optimization of key parameters to prepare an immunoassay like conjugation protein concentration, centrifugation time, electrolyte addition and assay temperature. We determined that saturating protein concentrations improved AuNPs surface coverage and uniformity of the assay and addition of sodium chloride improved sensitivity of the antibody detection method and assay stability. Furthermore, we showed that dynamic light scattering can be used to monitor changes in gold nanoparticles in the preparation and detection steps. Additionally, numerical simulations of the plasmonic optical response of AuNPs were carried out to scan for size-dependent response of the AuNPs. The AuNPs homogeneous immunoassay developed was further used in the detection of antibodies in vitro to detect Dengue virus infection.

A new type of gold nanoparticles was synthesized by using benzoyl pyrazolone as a capping agent. The synthesized AuNPs exhibited a spherical shape and a monodisperse and fluorescence emission characteristic peak at 650 nm. The AuNPs –BMPBP was demonstrated as sensitive and selective fluorescent chemosensor for detection of Al ³⁺ ion. In the presence of Al ³⁺ ion, the fluorescent emission of BMPBP-AuNPs at 650 nm, increased with an increasing concentration of Al ³⁺ ion with a low detection limit (2 µM), the proposed method provided to apply determination of Al ³⁺ ion of tap water with satisfactory results.

Artisanal and small-scale gold mining (ASGM) has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1) examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO) Expert Committee of Food Additives (JECFA)’s Provisional Tolerable Weekly Intake (PTWI); and (2), to measure the mercury levels of paco (Piaractus brachypomus) fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight). We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred) in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing distance away from the Madre de Dios headwaters (as the crow flies), did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute to human mercury exposure. More research is needed on human health risks associated with ASGM to discern occupational, residential, and nutritional exposure, especially through tracking temporal changes in mercury levels as fish ponds age, and assessing levels in different farmed fish species. Additionally, research is needed to definitively determine that elevated mercury levels in humans and fish result from the elemental mercury from mining, rather than from a different source, such as the mercury released from soil erosion during deforestation events from mining or other activities.

This study introduces an innovative approach to designing membranes capable of separating CO2 from industrial gas streams at higher temperatures. The novel membrane design seeks to leverage the well-researched high-temperature CO2 adsorbent, hydrotalcite, by transforming it into a membrane. This is achieved by combining it with an amorphous organo-silica-based matrix, extending the polymer-based Mixed Matrix Membrane concept to inorganic compounds. Following the membrane material preparation and investigation of the individual membrane in Part 1 of this study, we examine its permeation and selectivity here. The pure 200 nm thick hydrotalcite membrane exhibits Knudsen behavior due to large intercrystalline pores. In contrast, the organo-silica membrane demonstrates a permselectivity of 13.5 and permeance for CO2 of 1.3 107 mol m2 s1 Pa1 at 25°C, at 150°C the good separation behavior is reduced. Combining both components results in a hybrid microstructure, featuring selective surface diffusion in the microporous regions and unselective Knudsen diffusion in the mesoporous regions. Further attempts to bridge both components to form a purely microporous microstructure are outlined.

In agriculture, soil-borne fungal pathogens, especially Fusarium oxysporum strains, are posing a serious threat to efforts to achieve global food security. In the search for safer agrochemicals, silica nanoparticles (SiO2NPs) have recently been proposed as a new tool to alleviate pathogen damage including Fusarium wilt. Hollow mesoporous silica nanoparticles (HMSNs), a unique class of SiO2NPs, have been widely accepted as a desired pesticide carrier. However, their role in enhancing the disease resistance and the specific mechanism remain unknown. In this study, three sizes of HMSNs (19, 96 and 406 nm as HMSNs–19, HMSNs–96 and HMSNs–406, respectively) were synthesized and characterized to determine their effects on seed germination, seedling growth, and Fusarium oxysporum f. sp. phaseolus (FOP) suppression in cowpea roots by foliar spray using phenotypes, fresh biomass and disease progression as indicators. The results revealed that three HMSNs exhibited no adverse impacts on seed germination and tended to improve plant growth. Also, they exert their FOP suppression with a size- and concentration-dependent manner. HMSNs–406 possessed the best control effect at a concentration of 1000 mg/L showing an upto 40.00% decline in the disease severity. The Si(OH)4 control was also effective on FOP suppression at a lower concentration of 100 mg/L, whereas its higher concentrations exhibited obviously adverse impacts on FOP control, seed germination and plant growth. Moreover, we conformed that HMSNs posed their Fusarium wilt suppression in cowpea plant by activating SA (salicylic acid)-dependent SAR (systemic acquired resistance) responses rather than directly suppressing FOP. A higher level of SA content and elevated expression of its maker genes of PR-1 and PR-5 in HMSNs–406 treated cowpea roots provided substantial evidences of this mode of action. Other resistance-related genes, as well as defense-responsive enzymes, were also involved in the HMSNs-activated SAR pathway. Overall, for the first time, our results extended a new role of HMSNs as a potent elicitor to serve as a versatile alternative for plant disease protection of low cost, highly efficiency and sustainability.

In tire tread applications, achieving enhanced abrasion resistance, wet grip, and rolling resistance is crucial for optimizing overall performance. To realize improvements in these attributes for silica-filled tire tread compound, it becomes imperative to improve dispersity of silica filler with investigating the effect of each component in tire tread compound. In this work, we study the effect of styrene content within solution styrene butadiene rubber (SSBR) on the properties of tire tread compounds. A higher styrene segment within SSBR contributes to increased silica dispersion and crosslink density. Thus, tire tread compounds featuring SSBR with increased styrene content not only improve physical and mechanical properties but also enhance major characteristics tailored for tire tread applications. These findings provide valuable insights into advancing the reinforced performance of tire tread compounds through the strategic utilization of SSBR enriched in styrene content.

Polyhedral Oligomeric Silsesquioxanes (POSS) are one of the smallest silica nano particles. The presence of ordered ladder-like or cage conformation in their structure leads to remarkable thermal stability far greater than that for a linear polysiloxane. Reinforcement with nano particles is one of the recently favored strategy used to enhance the performance of polymers materials. The cyclic silica structure present in POSS ensures excellent thermal and mechanical stability. As a reinforcing filler, POSS can enhance the resistance of polymer matrix against pyrolysis and corrosion. In this paper, amine-terminated POSS with ladder like structure was synthesized by condensation of hydrolyzed aminosilane coupling agent. The ladder-like structure of POSS severely limits the motion of the chain backbone. The absence of phase transition for the synthesized POSS was confirmed by differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) was utilized to evaluate the thermal stability of POSS. TGA data show that the ladder-like POSS reported here has high char yield of about 75 % in nitrogen atmosphere and 54% in air atmosphere at 800℃. The TGA derivative curves show that the degradation of ladder-like POSS involves multiple stages and that the degradation rate is directly proportional to the heating rate. With the aid of Fourier Transform Infrared Spectroscopy (FT-IR), the cyclic structure of Si-O-Si bonding was determined to be the predominant structure. By analyzing the FTIR spectra of the cured POSS residue obtained at the specified temperatures, the detailed degradation mechanism of POSS was inferred. From the FTIR spectra of the low temperature cured samples, it was shown that the terminal silanol group was eliminated below 400℃. Some intermediate polymeric siloxane structures were observed by means of FT-IR and they eventually transitioned into silica which is the final product of pyrolysis of POSS. The presence of the FTIR transmission peaks at 1000 and 1100 cm-1, due to asymmetrical vertical and horizontal stretching of Si-O-Si, were the key evidence for the inferred ladder-like structure of POSS.

Several lime mortars for the repair of painted plasters of the rock cut church of Ss. Pietro and Paolo in Matera were studied. They were designed taking into account both aesthetic criteria that need to be fulfilled in the field of paintings restoration, and physical-mechanical compatibility with the original materials on site, i.e. the pre-existing plasters and the supporting rock. Mixes with calcareous and silica aggregates, based on different grain size proportions, were prepared for filling missing portions of the original painted plaster. The effects of the mineralogical nature and size of the aggregates on the characteristics and properties of the mixes were investigated in relation to the microstructure, physical-mechanical features and resistance to salt ageing. At the end of the experimental campaign, the overall performances were evaluated.

In this work the effect of recycled concrete aggregate modified with mineral admixtures and Nano-silica on the mechanical properties and performance of the concrete was investigated after curing in tap water for 28 and 90 days. The compressive, ƒc, indirect tensile, ƒt, and flexural, ƒb, strengths for cured concrete specimens were measured and concrete strength ratios were analyzed. The water and rapid chloride permeability were measured. SEM analysis of microstructure was, also, investigated. The coarse aggregates used were dolomite (control) and recycled concrete aggregate with the incorporation of different mineral admixtures including ground granulated blast slag and granite as well as Nano-silica. It was found that, the slump values of the dolomite concrete decreases compared with recycle aggregate concrete. The results indicate that, the concrete mix containing recycle aggregate have the highest compressive strength, tensile strength and flexural strength compered to concrete mix containing dolomite aggregate. As far as the compressive strength is concerned, the addition 1 % NS and 15 % of slag improved the physico-mechanical properties of the recycled aggregate concretes compared to the other mixes after curing in tap water.

This article deals with the possibility of partial replacement of blast furnace slag with fly ash after denitrification by the Selective Non-Catalytic Reduction (SNCR) method in alkali-activated materials. In the experiment, the basic physical-mechanical properties and durability properties were tested, the hydration reaction was monitored in a calorimeter and infrared spectroscopy was performed. Results were compared between mixtures prepared with fly ash without denitrification and also with reference mixture based only on alkali-activated blast furnace slag. The basic result is the finding, that hybrid alkali-systems with fly ash after denitrification show similar trends as hybrid alkali-systems with fly ash without denitrification. The significant effect of fly ash is manifested especially in terms of resistance to freeze-thaw. The reactions in the calorimeter show a slower development of reactions with increasing replacement of slag by fly ash. In the case of testing resistance to leaching in demineralised water, a decrease of flexural strength was found, which corresponds to the conclusions of strength testing, that long-term deposition of bodies in water causes deterioration of mechanical properties.

As the field of nanoscience is rapidly evolving, interest for novel, upgraded nanomaterials with combinatory features is also inevitably increasing. Hybrid composites, offer simple, budget-conscious and environmental-friendly solutions that can cater multiple needs at the same time and be applicable in many nanotechnology-related and interdisciplinary studies. The physicochemical idiocrasies of dendritic polymers have inspired their implementation as sorbents, active ingredient carriers and templates for complex composites. Ceramics are distinguished for their mechanical superiority and absorption potential that render them ideal substrates for separation and catalysis technologies. The integration of dendritic compounds to these inorganic hosts can be achieved through chemical attachment of the organic moiety onto functionalized surfaces, impregnation and absorption inside the pores, conventional sol-gel reactions or via biomimetic mediation of dendritic matrices, inducing the formation of usually spherical hybrid nanoparticles. Alternatively, dendritic polymers can propagate from ceramic scaffolds. All these variants are covered in detail. Optimization techniques as well as established and prospected applications are also presented.

Conventional radiation therapy uses white X-rays that consist of a mixture of X-ray waves with various energy levels. In contrast, a monochromatic X-ray (monoenergetic X-ray) has a single energy level. Irradiation of high Z elements with a synchrotron generated monochromatic X-ray with the energy at or higher than the K-edge energy of the element results in the production of the Auger electrons that cause DNA damage leading to cell killing. Delivery of high Z elements into cancer cells and tumor mass can be facilitated by the use of nanoparticles. Mesoporous silica nanoparticles (MSNs) have been shown to be effective in delivering high Z elements to cancer cells. A proof of principle experiment was reported that demonstrated the feasibility of this approach. This opens up a possibility to pursue the Auger cancer therapy by the combined use of MSNs loaded with high Z elements and monochromatic X-rays. Similar cancer therapies using other types of quantum beams such as neutron, proton and carbon ion beams can be envisioned.

During the casting in a warmer tropical temperature, a setting time delay is required to maintain the workability of the concrete, commonly achieved by the addition of admixtures i.e. silica fume (SF), fly ash (FA), and Plastrocrete®. However, high sugar content Coca-Cola in niche conditions is proposed as an ingredient for delaying concrete setting time in combination with conventional admixtures. This research aims to compare the setting time of admixtures from Coca-Cola and Plastocrete® RT6 plus in concrete mixing with control data of concrete mixed with SF or FA. The second aim is to measure the compression strengths between combinations of Coca-Cola and Plastocrete® RT6 plus. Concretes were produced with admixtures of SF, FA, Plastocrete® RT6plus, or Coca-Cola. The concrete used to control was f'c20 and f'c 25, while other concrete mixes were produced with the addition of Coca-Cola at 0.15% from the weight of cement at variation of moisture treatments. The first method to produce concrete (f'c20+Plas0.23%+Cola0.15% and f'c25+Plas0.23%+Cola0.15%) did not employ water reduction. The second concrete productions (f'c25+Plas0.46%+Cola0.15% and f'c25+Plas0.46%+Cola0.15%) reduced the addition of water at 8.8% (v/w). The first concrete production method had a setting time 44% longer than control. The reduced water concrete in the second productions had a setting time 34% longer than control. Meanwhile, the Plastocrete® RT6 Plus admixture with the reduced water delayed the concrete setting time by 26% longer than control. The delayed setting time of Plastocrete® RT6 Plus admixture with reduction of water was shorter than in the treatment with Coca-Cola. The combination of the addition of Coca-Cola with Plastocrete® RT6 plus by reducing the amount of adding Coca-Cola to 0.10% with Plastocrete® RT6 plus can delay concrete setting time by 51% longer than normal concrete and increase concrete compressive strength by 13% higher than normal concrete. Mixing Coca-Cola with Plastocrete® RT6 plus not only provided an optimal delay effect on setting time but also significantly increase the compressive strength that was desired during the casting in warm tropical weather applied in building construction of Mulawarman University, Samarinda, Indonesia.

Forensic detection of non-volatile nitro explosives poses a tough analytical challenge. A colorimetric sensor comprising ultrasonically prepared silica-dye microspheres was developed for sensitive gas detection of cyclohexanone, a volatile marker of explosives 1,3,5-trinitro-1,3,5-triazinane (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). The silica-dye composites were synthesized from the hydrolysis of ultrasonically sprayed organosiloxanes under mildly heating conditions (150 ^oC), which yields microspherical, nanoporous structures with high surface area (~300 m²/g) for gas exposure. The sensor inks were deposited on cellulose paper and gave sensitive colorimetric responses to trace amount of cyclohexanone vapors even at sub-ppm levels, with the detection limit down to ~150 ppb. The sensor showed high chemical specificity towards cyclohexanone against humidity and other classes of common solvents, including ethanol, acetonitrile, ether, ethyl acetate, and ammonia. Paper-based colorimetric sensors with hierarchical nanostructures could represent an alternative sensing materials for practical applications in the detection of explosives.

The study of localized surface plasmons (LSPs) in nanoscale structures is an essential step towards identifying optimal plasmonic modes that can facilitate robust optomechanical coupling and deepen our understanding of light-matter interactions at the nanoscale. This paper investigates numerically, using the finite element method, LSPs modes in a design comprising two coupled nano-ridges deposited on a gold layer, with an interposing polymer spacer layer. Such a structure, usually referred to as particles-on-mirror, shows exquisite optical properties at the nanoscale. We first examine the LSPs modes of a single nano-ridge through the analysis of its scattering cross-section in the visible and infrared range. To enhance the plasmonic response, a thin polymer layer is placed at the middle of the ridge, which introduces additional LSPs modes confined within the former. Then, we extend the analysis to the dimer configuration, which exhibits more complex and enhanced plasmonic behavior compared to a single nano-ridge. In particular, the dimer configuration yields LSPs resonances with a quality factor enhancement of approximately threefold relative to single nano-ridge. Furthermore, the presence of the polymer layer within the ridges significantly improves plasmon field localization and quality factor. These findings underscore the potential of nano-ridge-based structures in advancing optomechanical coupling and plasmon-phonon interaction studies, offering valuable insights for the development of high-performance acousto-plasmonic devices. In particular, the proposed device could help significantly improve the design of nano-acousto-optic modulators operating in the visible or in the near infrared, that require enhanced light-photon coupling rate.

The integration of commodities into stock exchanges marked a pivotal moment in the analysis of price dynamics. Commodities, essential for both daily sustenance and industrial processes, encompass hard commodities like metals and energy, alongside soft commodities such as agricultural produce. This paper investigates the implications of commodity price volatility on commercial and financial landscapes, recognizing its profound impact on global economies. This study employs a meticulous methodology, delineated into four stages: identification, control, and final selection of academic articles, culminating in their tabulation. Methodologically, a literature review serves as the primary tool for data acquisition, with a focus on existing scientific knowledge to bridge gaps and propose avenues for further inquiry. Drawing from reliable sources, including Google Scholar and Science Direct, the research navigates through a wealth of scholarly discourse on commodity market dynamics. By analyzing trends in academic publications, particularly focusing on the interplay between volatility spillover and gold, this paper provides insights into the evolution of research paradigms over time. Ultimately, this paper not only synthesizes existing knowledge but also identifies lacunae for future investigation, thereby contributing to a deeper understanding of the complexities surrounding commodity markets and their ramifications on global economies.

Gold occurrence Maljavr, located in amphibolite metamorphosed rocks in the Uragubsky greenstone belt, is the first gold prospect connected with conglomerates of Archean age, found in the Fennoscandian Shield. Gold mineralization is controlled by a series of lenses of altered rocks in biotite gneiss-metaconglomerate. The age of zircon from biotite gneiss in the zone of alteration is 2665±22 Ma, this is considered as the time of alteration processes. Biotite gneiss and altered rocks were later intruded by tourmaline granite pegmatite at 2508±7Ga, the pegmatite caused recrystallization of sulfide minerals in the altered rocks. Visible gold in association with bismuth minerals native bismuth, ehrigite (the second finding in the world), maldonite, bismuthinite, joseite-B, hedleyite was found exceptionally in polymineral inclusions in recrystallized arsenopyrite and löllingite. The age of pegmatite 2508±7Ma we regard as the time of formation of gold-bismuth mineralization. Geological position of the Maljavr occurrence, the linkage of gold mineralization with pegmatite, geochemical association Au-As-Se-Te-Bi in the mineralized rocks – all these characteristics correspond to intrusion-related gold deposits. Biotite gneiss-metaconglomerate, hosting the mineralized altered rocks, was the probable primary source of arsenic and gold for mineralization.

This study employs traditional OLS (ordinary least squares) regression analysis to investigate the influence of various external factors on Bitcoin price fluctuations from January 2014 to March 2023 using a multidimensional approach. We use factors from the traditional financial market, such as economic policy uncertainty (EPU), oil prices, the NASDAQ index, and gold prices, to identify factors contributing to Bitcoin volatility. Considering the unique situation in the Bitcoin market, that is, 24-hour trading and the short duration of its existence, we incorporate the broadest possible data range to achieve alignment between Bitcoin data and other datasets. The findings of the statistical analysis indicate that EPU and the NASDAQ index promote positive fluctuations in Bitcoin volatility, whereas gold prices act as a dampener. However, we find no empirical support for the influence of energy prices on Bitcoin volatility. These results suggest that Bitcoin should not be underestimated; all stakeholders should treat the issue of Bitcoin volatility seriously, including governments, who should actively regulate the Bitcoin market, and investors, who should recognize the dangers of this volatility, making rational decisions based on individual circumstances and employing flexible trading strategies.

Marine sediment sample was collected and the total aerobic population was counted and probiotic Bacillus cereus was isolated. Then it was mixed with formulated feed by spraying, while control diet was purchased from a local aquarium. 30 days of feeding experiment was conducted. Carassius auratus fishes were randomly divided into two experimental groups in rectangular tanks. The first group served as a control in which fishes were fed with commercial feed. The second group of fish were fed with probiotic incorporated feed. After 40 days, their survival and growth performance were detected. Bacillus cereus incorporated feed significantly yielded higher survival rate of the fish compared to control. Food conversion ratio (FCR) was significantly lower than the control group. The main aim of this work is to investigate the effect of a marine probiotic bacteria, Bacillus cereus on the survival and growth performance of gold fish Carassius auratus.

November 15th, 2022 was selected as the day where the human population reached the 8 billion mark [1]. This new reality will force the governments around the world to find ways to sustainably produce and secure food, water, and energy for their countries [2-4]. In terms of water, its quality and availability has been a matter of great concern in recent decades [5], especially with the emergence of new organic and inorganic pollutants [6]. Among organic contaminants, the detection of trace amounts of fluoroquinolone antibiotics, such as ciprofloxacin (CFX) and levofloxacin (LFX), in natural water bodies, has been of great concern in the scientific community [7,8]. Some of the side effects of the consumption of these antibiotics are nausea, diarrhea, abdominal pain, rash, low sugar levels, and antibiotic resistance to bacterial infections, among others [9,10]. It was estimated that in 2019 more than 1.27 million people died due to antibiotic-resistant bacterial infections [11], and this number is expected to rise to 10 million by 2050, if the trend continues [12]. Because of this, new ways to degrade antibiotics from water have been developed over the years. A method that has been implemented for some time is the use of photocatalysts for the degradation of these compounds in water [13]. Semiconductors such as titanium oxide (TiO2), zinc oxide (ZnO), zinc sulfide (ZnS), cadmium sulfide (CdS), strontium peroxide (SnO2), or tungsten trioxide (WO3), among others, are commonly used in photocatalytic processes [14-16]. Zinc oxide has been widely used due to its low cost and stability in aqueous solution, easy production, and because it is an environmentally friendly material [17,18]. It has been identified that some of the disadvantages of ZnO as photocatalyst are photocorrosion, recombination of electron-hole pairs, fast backward reactions, and inability to use visible light [18]. Multiple approaches have been implemented over the years to reduce these limitations. One of them is the use of noble metals such as platinum (Pt), gold (Au), or even silver (Ag) as cocatalysts [15-17,19]. These metals can increase the photocatalytic activity by reducing the recombination of electron-hole pairs, as well allowing the use of visible light [20]. For example, Quin and coworkers [21] prepared a bio-inspired hierarchical assembly of carbonized spinach leaves@Au/ZnO for the degradation of CFX under visible light. The results showed a degradation of 61% of the antibiotic in a period of 180 minutes. Chankhanittha et al. [22] developed different Ag@ZnO composites for the complete degradation of red dye and ofloxacin antibiotic in 25 and 80 minutes, respectively. The researchers attributed the improved photoactivity to the high electron-hole separation efficiency at the photocatalyst interface, as well as the creation of the Schottky barrier at the silver-zinc oxide interface.

Due to their well-defined plasmonic properties, gold nanorods (GNRs) can be fabricated with optimal light absorption in the near-infrared region of the electromagnetic spectrum, which make them suitable for cancer-related theranostic applications. However, their controversial safety profile, as a result of surfactant stabilization during synthesis, limits their clinical translation. We report a facile method to improve GNR biocompatibility through the presence of sodium dodecyl sulfate (SDS). GNRs (120 x 40 nm) were synthesized through a seed-mediated approach, using cetyltrimethylammonium bromide (CTAB) as a cationic surfactant to direct the growth of nanorods and stabilize the particles. Post-synthesis, SDS was used as an exchange ligand to modify the net surface charge of the particles from positive to negative while maintaining rod stability in an aqueous environment. GNR cytotoxic effects, as well as the mechanisms of their cellular uptake, were examined in two different cancer cell lines, Lewis lung carcinoma (LLC) and HeLa cells. We not only found a significant dose-dependent effect of GNR treatment on cell viability but also a time-dependent effect of GNR surfactant charge on cytotoxicity over the two cell lines. Our results promote a better understanding of how we can mediate the undesired consequences of GNR synthesis byproducts when exposed to a living organism, which so far has limited GNR use in cancer theranostics.

The requirements for using noncyanide imitation gold plating as decorative electroplating are increasing; thus, continuously improving the quality of the coating of the imitation gold plating and optimizing the coating process have become the current priority. In this work, hydroxyethylidene diphosphonic acid (HEDP) was used as the main complexing agent, CuSO4·5H2O, ZnSO4·7H2O and NaSnO3·3H2O were the main salts, and NaOH and anhydrous sodium carbonate were used as the buffers to prepare the electroplating solution. Using sodium citrate (SC), sodium potassium tartrate (SS), sodium gluconate (SG), and glycerol (Gl) as four additives, the effects of the number of carboxyl groups on the properties of a Cu-Zn-Sn alloy coating were compared. The electrochemical analysis showed that Cu-Zn-Sn alloy codeposition occurred at -0.50 V vs. Hg|HgO. The scanning electron microscopy (SEM) results showed that the particle size of the coatings obtained with carboxyl-containing additives was more uniform than that obtained with the electroplating solution without additives. The X-ray fluorescence spectrometry (XRF) analysis revealed that the composition of the Cu-Zn-Sn alloy coating obtained by using SC as an additive in the electroplating solution was 89.75 wt% Cu, 9.61 wt% Zn, and 0.64 wt% Sn, and the color of the coating was golden yellow. The X-ray diffraction (XRD) pattern showed that the coating was a mixture of Cu, Cu5Zn8, CuSn, Cu6Sn5, and CuZn phases. The analysis of the electroplating solution by UV, IR and NMR spectroscopy methods indicates that the additives improve the coating by affecting the complexation reaction of metal ions. These results can provide technical and theoretical guidance for developing Cu-Zn-Sn ternary alloy electrodeposition technology with the new cyanide-free HEDP alkaline electroplating system.

Silver and gold nanoparticles are a promising tool for medical and industrial application, therefore, their ecotoxicity should be carefully examined. The effect of silver (12 nm) and gold (4.7) nanoparticles coated with polyethylene glycol on Spirulina platensis biomass growth and biochemical composition was investigated. The spirulina cultivation medium was supplemented with nanoparticles in concentration range 0.025-0.5 µM. Given concentrations stimulated spirulina biomass growth, while content of proteins, carbohydrates and auxiliary pigments was affected insignificantly by presence of nanoparticles in cultivation medium. The pronounced effect of gold nanoparticles at concentration 0.5 µM on the lipids content was observed. TEM images demonstrate that nanoparticles penetrate inside the cell, resulting in ultrastructural changes in cells.

The present work encompasses an application-oriented perspective to the possible employment of gold nanoparticles as nanomedicine in cancer therapeutics. The rationale of the work lies in the growing needs for assessment of advanced alternative treatment of cancer employing functionalized nanoparticles as nanomedicine. Gold nanoparticles fabricated via green chemistry methods by leaves of a time-honored medicinal plant, Piper betle were ascertained for their synthesis and properties under the umbrella of characterization of nanoparticles, through various techniques like UV-vis spectroscopy, FTIR spectroscopy, X-ray diffraction, and scanning electron microscopy. The cytotoxicity assay of well-characterized gold nanoparticles was monitored against lung cancer cell line (A549) by metabolic and imaging assays. MTT assay or the metabolic assay was performed for a range of nanoparticles’ concentrations. The results were promising and proved to be a leading-edge venture, envisaging the possibility of gold nanoparticles for cancer therapeutics.

Techniques of stripping voltammetry (SV) determination of silver and gold in pyrites and carbonaceous matter were developed. The problem of quantitative transfer of the sample into the solution was solved. For this purpose, the ore matrix of carbonaceous shales was decomposed by mineral acids in autoclaves at high pressures. The element to be determined from the sample matrix was separated by extraction. Ag(I) ions from the solutions were extracted in the form of dithizonate complex in CCl₄. Au(III) ions were extracted by diethyl ether. The extracts were decomposed thermally. The dry residue was dissolved in the background electrolyte, and the element was determined by the SV method. The graphite electrode (GE) impregnated with polyethylene was used as a working electrode in SV–determination of silver. SV–determination of gold was carried out using GE modified by bismuth. The limits of detection (LOD) of Ag(I) and Au(III) contents were equal to 0.016 mg L^-1 and 0.0086 mg L^-1, respectively. The results of SV-determination of gold and silver in standard samples, pyrites and carbonaceous shales were presented. The silver content in the pyrite was 13.6 g t^-1, in carbon shale—0.34 g t^-1. The concentration of gold in the pyrite ore zone "Kirovsko–Kryklinskaya" was 1.15 g t^-1; in carbonaceous shales—2.66 g t^-1. The obtained data were consistent with the data of atomic emission spectroscopy (AES) and inductively coupled plasma mass spectrometry (ICP—MS). The error of determination of elements by stripping voltammetry was calculated when determining the silver content of 10...6 g t^-1 in pyrite and carbonaceous material, which was less than 12%, and when determining the gold content of 1...3 g t^{- 1} in pyrite and carbonaceous matter, which was less than 23%.

In this study we fabricate gold nanocomposites and model their optical properties. The nanocomposites are either homogeneous films or gratings containing gold nanoparticles embedded in a polymer matrix. The samples are fabricated using a recently developed technique making use of laser interferometry. The gratings present original plasmon-enhanced diffraction properties. In this work, we develop a new approach to model the optical properties of our composites. We combine the extended Maxwell-Garnett model of effective media with the Rigorous Coupled Wave Analysis (RCWA) method and compute both the absorption spectra and the diffraction efficiency spectra of the gratings. We show that such a semi-analytical approach allows us to reproduce the original plasmonic features of the composites and can give us entails about their inner structure. Such approach could be a simple and efficient tool to study complex micro-structured system based on plasmonic components, such as metamaterials.

The preparation of gold nanoparticles (AuNPs) involves a variety of chemical and physical methods. These methods use toxic and environmentally harmful chemicals. Consequently, the synthesis of AuNPs using green chemistry has been under investigation to develop eco-friendly nanoparticles. One method to achieve this is the use of plant-derived phytochemicals capable of reducing gold ions to produce AuNPs. The aim of this study was to implement a facile microtitre-plate method to screen a large number of aqueous plant extracts to determine the optimum concentration (OC) to bio-synthesize the AuNPs. Several AuNPs of different sizes and shapes were successfully synthesized and characterized from seventeen South African plants. The characterization was done using Ultra Violet-Visible Spectroscopy, Dynamic Light Scattering, High Resolution Transmission Electron Microscopy and Energy-Dispersive X-ray Spectroscopy. We also studied the effects of temperature on the synthesis of the nanoparticles and measured its effect on the particle size of the synthesized AuNPs and the data showed that changes in temperatures affect the size and dispersity of the generated AuNPs. Further, some of the synthesized AuNPs were stable upon incubation with different biological solutions in vitro.

A major problem of the technological production process of the metallurgical-grade silicon is formation of a large amount of microsilica. However, this material can be a significant source of raw materials for its own production. Hence, this study is aimed to solve the problem of micro-silica utilization, i.e. the technogenic dust-like waste generated during the melting of the technical-grade silicon. Within this study, the technology of the joint briquetting of microsilica was investigated with the carbonaceous reducing agents, i.e. by obtaining of mono-charge and by melting of the technical-grade silicon from the obtained mono-charge in the 200kVA ore-thermal furnace. Results of the study show that the briquettes in the melting process of the technical-grade silicon can be used in the range from 0 to 50%. The using of briquettes may significantly improve the technological parameters. When briquetted charge is applied only, the technological parameters will deteriorate significantly. The material balance of silicon melting showed the recovery rates of the main elements (Si, Al, Ca and Fe). It recorded a decrease in content of aluminum from 1.9-2.1% to 0.5-0.7%, calcium from 0.2-0.3% to 0.07-0.1% and titanium from 0.2-0.23% to 0.11-0.13% during the transition to briquetted monocharge. Phosphorus content increased from 0.004-0.005 to 0.011-0.013%.

The development of photocurable compositions is in high demand for the manufacture of func-tional materials for electronics, optics, medicine, energy, etc. The properties of the final pho-to-cured material are primarily determined by the initial mixture, which needs to be tuned for each application. In this study we propose to use simple systems based on di(meth)acrylate, polyimide and photoinitiator for the preparation of new photo-curable compositions. It was es-tablished that a fluorinated cardo copolymide (FCPI) based on 2,2-bis-(3,4-dicarboxydiphenyl)hexafluoropropane dianhydride, 9,9-bis-(4-aminophenyl)fluorene and 2,2-bis-(4-aminophenyl)hexafluoropropane (1.00:0.75:0.25 mol) has excellent solubility in di(met)acrylates. This made it possible to prepare solutions of FCPI in such monomers, to study the effect of FCPI on the kinetics of their photopolymerization in situ and the properties of the resulting polymers. According to the obtained data, the solutions of FCPI (23 wt.%) in 1,4-butanediol diacrylate (BDDA) and FCPI (15 wt.%) in tetraethylene glycol diacrylate were tested for the formation of the primary protective coatings of the silica optical fibers. It was found that the new coating of poly(BDDA–FCPI23%) can withstand prolonged annealing at 200°C (72 h), which is comparable or superior to the known most thermally stable photo-curable coatings. The proposed approach can be applied to obtain other functional materials.

Silica on Silicon is a major optical integration platform, while the emergent class of integrated Laser written circuits' platform offers additionally high customizability, and flexibility for rapid prototyping. However, the inherent waveguides' low core/cladding refractive index contrast characteristic compared to other photonic platforms in silicon or silicon nitride, sets serious limitations for on-chip efficient coupling with single photon emitters, like semiconductor nanowires with quantum dots limiting the applications in quantum computing. A new light coupling scheme proposed here overcomes this limitation providing means for light coupling >50%. The scheme is based on the incorporation of an optical microsphere between the nanowire and the waveguide, properly optimized and arranged in terms of: size, refractive index, distance of microsphere between nanowire and waveguide. Upon suitable design of the optical arrangement, the photonic nanojet emitted by the illuminated microsphere excites efficiently the guided eigenmodes of the input channel waveguide, thus launching light with high coupling efficiency. The method is tolerant in displacements, misalignments, and imperfections and is fabricationally feasible by current state of the art techniques. The proposed method enables the on-chip multiple single photon emitters' integration thus allowing the development of highly customizable and scalable quantum photonic integrated circuits for quantum computing.

This comprehensive review explores recent advancements in heavy metal remediation techniques, focusing on the utilization of cellulose-silica composites and tailored surface modification techniques. We examine the synthesis strategies and properties of cellulose-silica adsorbents, highlighting their enhanced adsorption capacities and structural robustness for removing heavy metal pollutants from aqueous environments. The review investigates various surface modification approaches, including thiol-functionalization, amino acid grafting, and silane coupling agents, for optimizing the surface chemistry and morphology of cellulose-silica composites. Mechanistic insights into the adsorption processes and kinetics of modified adsorbents are discussed, along with considerations for optimizing adsorption performance under different environmental conditions. This review provides valuable perspectives on the development of effective adsorbent materials for sustainable heavy metal remediation applications.

This study investigates the contribution of nano-alumina (nA: 1-3wt.% binder) to the performance of silica fume (SF-10%) blended mortar in ternary blended mortar. The fresh (workability, setting time) and hardened properties (compressive strength and thermal resistance (300 °C for 1 h)), were examined. Nano alumina (nA) contributed positively to the consistency of SF blended mortar such that similar workability could be achieved with OPC when 3% nA was added. The initial and final setting time of 180 and 220 mins were recorded in SF blended mortar and reduced by 18.4 and 21.8%, respectively by adding 3%nA. The optimum mixture that contained 10%SF and 2%nA had 3-d and 28-d compressive strengths of 28 and 43.2 MPa. In the absence of nA, this reduced by 14.3% and 29.4% while it reduced by 25.2% and 16.7%, respectively in OPC mortar. The main products characterizing SF-nA ternary blended binder with dense microstructural density were nepheline and tobermorite. Besides, it is more susceptible to carbonation despite its superior performance in thermal resistance when compared to SF blended and OPC mortars.

Water pollution with dyes is a critical environmental issue because off the huge amount of dyes disbarred annually which cause severe damage for the ecosystem and human life. On the other hand, the core-shell based magnetic materials have showed amazing character for controlling the material synthesis with targeted structure to enhance the adsorptive-removal of pollutants. Herein, Fe3O4 core-TiO2/mesoSiO2 and Fe3O4 core-mesoSiO2/TiO2 double shell nanoparticles were prepared by first (R1) and second (R2) routes. The preparation procedure is controlled to prepare the magnetic core with further coating layers from silica and titania for the uptake of methylene blue from aqueous solutions. The reported adsorption capacities for R1-0.2, R1-0.4 and R2 samples were 46, 38 and 50 mg/g respectively at pH 6 after 80 min contact time form 50 ppm methylene blue solution. The adsorption process of methylene blue onto Fe3O4core-meso SiO2/TiO2 double shell was well fitted with the pseudo-second-order kinetic model and Freundlish isotherm which suggested the quick and multilayer adsorption mechanism. In addition, results of thermodynamic investigation indicated that the surfaces of Fe3O4 core-mesoSiO2/TiO2 and Fe3O4 core-TiO2/mesoSiO2 double shell exhibit spontaneous tendency to adsorb methylene blue from the aqueous solutions. These results will encourage the further application of Fe3O4 core-meso SiO2/TiO2 and Fe3O4 core-TiO2/meso SiO2 double shell for removal of other dyes and pollutants from wastewater.

Triglycerides of waste cooking oil reacted with methanol in refluxing toluene to yield mixtures of diglycerides, monoglycerides and fatty acid methyl esters (FAMEs) in the presence of 20% (w/w) catalyst/oil using the hydrophilic sulfonated silica (SiO₂-SO₃H) catalyst alone or with the addition of 10% (w/w) co-catalyst/oil [(Bun4N)](BF₄) or Aliquat 336]. The addition of the ammonium salts to the catalyst lead to a decrease in the amounts of diglycerides in the products, but the concentrations of monoglycerides increased. Mixtures of [(Bun4N)](BF4)/catalyst were superior to catalyst alone or Aliquat 336/catalyst for promoting the production of mixtures with high concentrations of FAMEs. The same experiments were repeated using DMSO as the solvent. The use of the more polar solvent resulted in excellent conversion of the triglycerides to FAME esters with all three-catalyst media. A simplified mechanism is presented to account for the experimental results.

Alkali-activated materials are alternative building binders, where secondary raw materials are processed. Possibility to use landfilled waste materials in their preparation, increases their potential application in construction practice, and therefore they are subject to extensive research, especially in recent years. This paper briefly summarizes interesting results of an experiment aimed at verifying the possibility of applying cement by-pass dust (CBPD) in the preparation of alkali-activated materials. The research work was focused on the possibilities of using these wastes for the preparation of small elements of garden architecture. The paper briefly evaluates in particular the results of X-ray diffraction, which were subjected to three types of binder pastes differing in the amount of used activator. In the experiment, a mixture of blast furnace granulated slag, fly ash and cement by-pass dust was alkali activated with sodium metasilicate.

This study is focused on the experimental investigation of compressive strength and durability properties of lightweight concrete mixtures with fine expanded glass and expanded clay aggregates using different microfillers. The paper proposes the relationships between the compressive strength and density of concrete mixtures with different proportions of lightweight aggregates mentioned above. The performed experimental studies have revealed the tendencies of possible usage of different amount of fine lightweight aggregates and their combinations in the production of concrete mixtures depending on the demands of practical application. Following the requirements for structural concrete subjected to environmental effects, durability properties (alkaline corrosion and freeze–thaw resistance) of the selected concrete mixtures with expanded glass aggregate were studied. The results of the experimental investigations have shown that durability of tested concrete specimens was sufficient. The study has concluded that the mixtures under consideration can be applied for the production of structural elements to which durability requirements are significant.

The Kraaipan and Amalia greenstone belts in South Africa occurs in the western part of the Kaapvaal Craton. The two belts stretch discontinuously in an approximately north-south orientation over a distance of about 250 km from southern Botswana in the north to the Vaal River near Christiana in the south and are separated by a distance of about 90 km. Gold mineralization is hosted in banded iron-formation at both the Kalahari Goldridge deposit (Kalgold) in the Kraaipan greenstone belt in the north, and the Amalia deposit in the Amalia greenstone belt in the south, with the mineralization associated with quartz-carbonate veins. The footwall of these deposits is generally composed of mafic volcanic schist and hanging wall consisting of graywackes, schist and shale units. The Kalgold and Amalia gold deposits show some variation in the redox condition of the mineralizing system, mineralization temperatures and fluid chemistry. The ore mineral assemblage is characterized by magnetite-pyrrhotite-pyrite at Kalgold, which is indicative of reducing conditions, and magnetite-hematite-pyrite assemblage at Amalia that suggest a relatively oxidizing environment. Average mineralizing temperatures determined from chlorite geothermometry were relatively higher at the Kalahari Goldridge deposit ranging from 350 to 400oC compared to 335 to 370oC (mean, 352± 18, n = 113) at Amalia. The composition of the fluids derived from fluid inclusions are indicative of low salinity H2O-CH4-CO2-rich fluids at Kalgold against relatively H2O-CO2-rich fluids at Amalia. Evidence from strontium-carbon-oxygen isotopic ratios from carbonates suggests differences in redox conditions in the deposits could be attributed to different flow pathways by the evolving fluid from a common source (with minimum 87Sr/86Sr=0.70354) to the sites of gold deposition; with significant ore fluid interaction with thick sequence of carbonaceous meta-pelitic rock units at the Kalahari Goldridge deposit, that is absent in the Amalia deposit.

The Minamata Disease in Japan was one of the most notorious public nuisance cases in the 1960s and 70s, but is still ongoing “unfinished business” in terms of victims’ protection even after several decades of struggles. The world standard of epidemiological causation has still been applied in limited cases. However, it has been pointed out in the international report that, in recent years, mercury contamination has decreased in countries in the Global North, except the Canadian Indigenous peoples’ case, at the same time that it has increased in the Global South. In the Amazon, many Indigenous peoples, most prominently, the Munduruku people in Para state and the Yanomami people in Roraima state, suffer from the Brazilian Minamata Disease due to mercury contamination differently as a typical case of global environmental injustice issues. This paper discusses the comparative difference of the Minamata Disease between inside and outside Japan: In Japan, accumulated mercury contamination in Shiranui Bay of Kyushu due to the poisonous waste release by a big corporation named Chisso Co. was serious, while in the Amazon, contamination due to gold mining by ASGM has been much broader and more diffused. Thus, civil law damages litigation has historically worked despite some challenges in Japan, while it’s practically impossible to stop numerous small scale gold mining by judicial approach in the Amazon. Instead, the administrative regulation under the Lula administration contrasted to the Bolsonaro administration might be especially important, although it’s still limited, considering the global demand for gold and related continuous gold mining activities. Minamata Disease symptoms among the Indigenous peoples along the Amazon are generally minor compared to the Japanese case, but they should also be considered the case from the liberal standard that criticizes the traditional stringent standard such as the Hunter=Russell criteria. However, facing the worsening situation of mercury contamination, the challenges in the Global South are serious: The effective measures for their global health are limited except for dietary education to avoid poisonous carnivorous fishes as opposed to herbivorous fishes. International assistance for providing clean water is also imminent agenda.