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.

Chemical flooding is one of the effective methods to recover large volumes of oil from sandstone formations after primary depletion. However, silica dissolution often occurs during Alkaline-Surfactant-Polymer (ASP) flooding, affecting the petro-physical properties of the formation. To address this issue, samples from Berea sandstone formations were treated with various brine solutions, through static tube tests and core flooding experiments. Analytical tests such as DR/2800 spectrophotometer and scanning electron microscope were used to evaluate the silica solubility and the alteration in mineral content. The results indicated that the silicate contents decreased after the saturation due to silica solubility in the solution. Increasing brine salinity to 40,000ppm and introducing Magnesium and Calcium ions to the solution, reduces the silicate contents by 5.03 % and 7.32 %. Moreover, saturating the samples with ASP solution, further reduced the silicate contents by 14.86 %. This reduction is associated with a relative increase in silica solubility and pH of the solution. Silica dissolution affects the pore microstructure, which resulted in increasing the porosity and pore volume after the core flooding. The injection of the ASP solution increased the porosity by 5.83%, thus the pore volume increased from 17.72 to 18.76cc. This is associated with the high silica solubility and the increase of solution pH in the ASP solution. The permeability of the samples generally reduced after the core flooding, due to the silica solubility. However, injecting the ASP solution, resulted in a major reduction of the permeability by more than 75%. These changes in the petro-physical properties can lead to severe formation damage, and affect hydrocarbon production. This study assists in understanding the impact of silica dissolution during ASP treatment and addresses the factors involved. Efficient utilization of chemical flooding can help mitigating silicate scaling within the formation, and extend field productivity.

Quite a number of cottonseed varieties are existed. The seeds of each variety produce a different amount of gossypol as a natural toxic compound. The increased interest in this natural product and its toxic effects were enhanced the demand for establishing simple silica-gel-based methods for its isolation, purification, and characterization. Historically, silica gel plays a significant role in isolation and purification of many different natural products. Silica gel is variants and can intro-duce a lab, simple tool for tracking a compound in certain plants during its purification process. In this study, gossypol was isolated and purified in the form of yellow crystals as gossypol acetic ac-id. Several methods and tools were used for its characterization including TLC, preparative TLC, silica gel column, UV/IR spectrophotometer and HPLC (Robust spherical silica gel). A compara-tive study between its amounts in both Egyptian and Chinese varieties were performed. Under the experimental condition, the Egyptian cottonseeds contain 8.705 gm/kg, while the Chinese contains 5.395 gm/kg. Thin Layer Chromatography (TLC) had been flourished the science of the phytochemistry and still popular till nowadays and is recommended for fast, accurate, and inex-pensive evaluation and quantification of gossypol. It is recommended to isolate and purify gossy-pol as gossypol acetic acid using optimized combined methods used in this study. Using Silica gel different protocols will assist and facilitate the parallel comparison and save the compact column from any unexpected contaminants during the purification steps. During each step the silica gel itself could be simply removed by paper filtration.

The aim of this manuscript is to synthesize and characterize novel silylated Sm3+ and Eu3+ complexes and incorporate them into mesoporous silica nanoparticles (MSNs) and dense silica nanoparticles (DSNs). Sm3+ and Eu3+ ion complexes were chosen for their strong UV-visible emission, deep-red luminescence, and effective interaction with bidentate organic ligands, such as 2-thenoyltrifluoroacetone (tta) and 1,10-phenanthroline (phen). Silylated ligands were employed as coupling agents to form covalent bonds between the complexes and an oxide matrix via a conventional sol-gel process. This approach aims to enhance the thermal stability and photophysical properties of the resulting hybrid material compared to free complexes. The new silylated-bidentate ligand complexes, using tta and phen as organic ligands and 3-chloropropyltriethoxysilane as the silylating agent, were characterized by FTIR, luminescence spectroscopy, and luminescence decay. After incorporation into silica nanoparticles, the hybrid materials were characterized by SEM, TEM, DLS, zeta potential, SAXS, porosity, surface area measurements, luminescence spectroscopy, and MTT assay. The results confirm the successful synthesis of new luminescent silylated complexes with high luminescence intensity and their incorporation into silica nanoparticles.

Fish oil rich in docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), vitamin D₃ and natural astaxanthin sustainably extracted from anchovy fillet leftovers using biobased limonene only, can be conveniently stabilized by adsorption on periodic mesoporous silicas. The simplicity of the process, the high load of entrapped fish oil, and the biocompatible nature of silica support numerous forthcoming applications of this new class of “Omeg@Silica” materials.

The potato is the most important non-cereal food crop, and thus improving potato growth and yield is in the focus of agricultural researchers and practitioners worldwide. Several studies reported beneficial effects of silicon (Si) fertilization on potato performance, although plant species from the family Solanaceae are generally considered as non-Si-accumulating. We used results from two field experiments in the temperate zone to gain insight into silica accumulation in potato plants as well as corresponding long-term potato yield performance. We found relatively low Si contents in potato leaves and roots (up to 0.08% and 0.3% in the dry mass, respectively) and negligible Si contents in potato tuber skin and tuber flesh for plants grown in soils with different concentrations of plant available Si (field experiment 1). Moreover, potato yield was not correlated to plant available Si concentrations in soils in the long-term (1965-2015, field experiment 2). Based on our results we ascribe the beneficial effects of Si fertilization on potato growth and yield performance reported in previous studies mainly to antifungal/osmotic effects of foliar-applied Si fertilizers and to changes in physicochemical soil properties (e.g., enhanced phosphorus availability and water holding capacity) caused by soil-applied Si fertilizers.

Rice cultivation stands as a cornerstone of Sri Lanka's economy, serving as a vital source of em-ployment for rural communities. However, the constraints of limited land availability have prompted an escalating dependence on agrochemicals, notably for pest management, thereby posing significant threats to human health and the environment. This review delves into the ex-ploration of silica nanoparticles as a promising eco-friendly substitute for conventional pesticides in the context of Sri Lankan rice farming. It comprehensively examines various aspects including the synthesis methods of silica nanoparticles, their encapsulation with synthetic pesticides, and an evaluation of their efficacy in pest control. Furthermore, it sheds light on the innovative utilization of agricultural waste such as rice husk and straw in the production of silica-based nano-pesticides. This approach not only demonstrates a shift towards sustainable agricultural practices but also aligns with the principles of green chemistry and circular economy, offering a holistic solution to the challenges faced by the rice farming sector in Sri Lanka.

As the major greenhouse gas, CO2 gas emission has been noticeably increased over the past decades resulting in global warming and climate change. As a result, it is imperative to reduce the excess CO2 in the atmosphere to hold “the increase in the global average temperature to well below 2°C (ideally 1.5°C) above pre-industrial levels set by the Paris Agreement on climate change. Among many ways, CO2 capture technology is considered as the most promising technology among the available technologies. Porous materials such as carbons, silica, zeolites, hollow fibers, and alumina are widely used as CO2 sorbents. However, among the available porous sloid sorbents, porous silica-based materials grabbed a significant attention due to their unique properties including high surface area, pore volume, good thermal and mechanical stability, and low cost. Therefore, development of porous silica materials as a promising CO2 absorbent is a continuously expanding research area in the current moment. Herein, we aim to visualize a full picture of the porous silica-based materials for CO2 capture. This review presents a comprehensive study of existing CO2 capture techniques and highlights the recent progress of different porous silica materials and synthesis processes. CO2 adsorption capacities of unmodified porous silica materials are less effective as compared with functionalized silica materials. Various research activities have been reported about functionalization of pours silica using amine groups. Therefore, in this review, different synthesis routes of amine-functionalized porous silica materials, CO2 adsorption capacities, gas selectivity and reusability were discussed. Moreover, the research challenges associated with the porous silica materials and future research directions are summarized.

This research evaluates the technical and financial feasibility of using Inhibitor A for brine treatment in geothermal energy production, comparing it with traditional brine acidification. Conducted at a geothermal site in Central Java, Indonesia, the study uses Decision Tree Analysis and risk Expected Monetary Value (EMV) to assess both methods. Inhibitor A demonstrates a 70% reduction in scaling compared to untreated brine, with laboratory tests indicating a 10 ppm dosage as optimal for minimizing silica scaling. Despite higher initial costs, Decision Tree Analysis shows that Inhibitor A has a lower overall risk profile than acidification. EMV analysis confirms its cost-efficiency when considering potential risks and benefits. This research advocates for the adoption of Inhibitor A, highlighting its long-term benefits and sustainability over traditional methods. The findings emphasize the importance of innovative solutions in enhancing geothermal energy systems’ efficiency and sustainability. By integrating technical performance with financial analysis, this study provides a comprehensive evaluation to inform decision-making in the geothermal sector, promoting more effective and sustainable brine treatment practices.

The composites of heteropolyacids (H3PW12, H3PMo12) incorporated into amine-functionalized silica materials, were used for the first time as heterogeneous catalysts in the valorisation of glycerol (a large waste from biodiesel industry) by acetalization reaction with acetone. The polyoxotungstate catalyst H3PW12@AptesSBA-15 presented higher catalytic efficiency than the phosphomolybdate, with 97% of conversion with 97% of solketal selectivity, after 60 min at 25 °C, or 91% of glycerol conversion and the same selectivity, after 5 min, performing the reaction at 60 ºC. A relation of catalytic performance and acidity of the catalyst is here presented. Furthermore, the stability of the solid catalyst was investigated and discussed.

Mineral surfaces have been demonstrated to play a central role in prebiotic reaction, which are supposed to be at the basis of the origin of life. Among the various molecules proposed as precursors for these reactions, one of the most interesting is formamide. Formamide has been shown to be a pluripotent molecule, generating a wide distribution of relevant pre-biotic products. In particular, the outcomes of its reactivity are strongly related to the presence of mineral phases, acting as catalysts toward specific reaction pathways. Even if the mineral-products relationship has been deeply studied for a large pool of materials, the fundamental description of the formamide reactivity over the mineral surface at a microscopic level is missing in the literature. In particular, a key step of formamide chemistry at surfaces is its adsorption on the available interaction sites. This report aims to investigate the adsorption of formamide over a well-defined amorphous silica, chosen as model mineral surface. An experimental IR investigation of formamide adsorption has been carried out and its outcomes have been interpreted on the basis of first principles simulation of the process adopting a realistic model of the amorphous silica.

Nowadays, the study of preparing silica/rubber composites, which can be used in “green tire”, in energy saving method is fast-growing. In our work, silica modified by using alcohol polyoxyethylene ether (AEO) and 3-Mercaptopropyltriethoxysilane (K-MEPTS) together were investigated. Thermal gravimetric analyzer (TGA) result indicated that both AEO and K-MEPTS could be grafted on the silica surface. Raman spectroscopy confirmed that the AEO could generate a certain steric hindrance for the mercaptopropyl group on K-MEPTS. Silica modified by using AEO and K-MEPTS together can be completely co-coagulated with the rubber in preparing silica/natural rubber (NR) composites by latex compounding method. AEO can form a physical interface between silica and rubber; meanwhile, K-MEPTS can form a chemical interface between silica and rubber. The effects of chemical and physical interface between silica and rubber on dynamic and mechanical performances of silica/NR composites were also given in this research. A proper combination of physical and chemical interface between silica and NR can improve performances of silica/NR composites.

Nanoparticle carriers can selectively deliver the drug cargo to tumor cells, thus having the ability to pre-vent early drug release, reduce non-specific cell binding, and prolong in vivo drug retention. We con-structed paclitaxel (PTX)-loaded lipid-shell mesoporous silica nanoparticles (LMSNs) for targeted an-ti-cancer drug delivery. The physical properties of PTX-LMSNs were analyzed by scanning electron mi-croscopy (SEM) and transmission electron microscopy (TEM). The drug loading (DL%) and entrapment efficiency (EE%) of PTX-LMSNs were measured by high performance liquid chromatography (HPLC). In vitro drug release test, in vivo imaging, tissue distribution and pharmacokinetics of PTX-LMSNs were also evaluated. The SEM examination showed that MSNs were sphere, whereas TEM showed that they were rich in fine pores. The uniform core-shell structure of PTX-LMSNs was also verified by TEM. The DL capacity of PTX-LMSN was as high as 21.75%, and PTX was released from the nanoparticles in vitro in a pH-dependent manner. The cumulative amount of free PTX increased at lower pH, which is conducive to selective drug release from LMSNs in the acidic tumor tissues. In vivo imaging showed prolonged reten-tion of PTX-LMSNs, which is beneficial to their therapeutic efficacy. In addition, PTX-LMSNs were primarily concentrated in the liver. Pharmacokinetic experiments showed that the half-life of PTX-LMSNs was 23.21% longer and 79.24% higher than that of Taxol. Together, LMSNs are a highly promising antineoplastic drug carrier system.

Elevated antimony concentrations in aqueous environments from anthropogenic sources is becoming of global concern, here iron oxides are known to strongly adsorb aqueous antimony species with different oxidation states, but the effect of silica on the removal characteristics is not well understood despite being a common component in the environment. In this study, ferrihydrite was synthesized at various Si/Fe molar ratios to investigate its adsorption and co-precipitation behaviors with aqueous antimony anionic species, Sb(III) and Sb(V). The XRD analyses of the precipitates showed two broad diffraction features at approximately 35° and 62° 2θ, which are characteristic of 2-line ferrihydrite, no significant shifts in peak positions in the ferrihydrite regardless of the Si/Fe ratios. The infrared spectra showed a sharp band at ~990 cm⁻¹, corresponding to asymmetric stretching vibrations of Si-O-Fe bonds which increased in intensity with increasing Si/Fe molar ratios. Further, the surface charge on the precipitates became more negative with increasing Si/Fe molar ratios. The adsorption experiments indicated that Sb(V) was preferentially adsorbed at acidic conditions and decreased dramatically with increasing pH while the adsorption rate of Sb(III) ions was independent of pH, however, the presence of silica suppressed the adsorption of both Sb(III) and Sb(V) ions. The results showed that Sb(III) and Sb(V) ions were significantly inhibited by co-precipitation with ferrihydrite even in the presence of silica by isomorphous substitution in the ferrihydrite crystal structure.

Antimicrobial peptides (AMPs) have emerged as a promising solution to tackle bacterial infections and combat antibiotic resistance. However, their clinical application has been hindered by their vulnerability to protease degradation and toxicity towards mammalian cells. To overcome these challenges, our study aims to develop a method to enhance the stability and safety of AMPs, applicable to effective drug-device combination products. KR12 antimicrobial peptide was chosen and in order to further enhance its delivery and efficacy, HIV TAT protein-derived cell-penetrating peptide (CPP) was fused to form CPP-KR12. A new product, CPP-KR12@Si, was developed by forming silica nanoparticles with self-entrapped CPP-KR12 peptide using the biomimetic silica precipitability due to its cationic nature. Peptide delivery from CPP-KR12@Si to bacteria and cells was delivered at a slightly delayed rate with improved stability against trypsin treatment and a reduction in cytotoxicity over CPP-KR12. Finally, the antimicrobial potential of CPP-KR12@Si/bone graft substitute (BGS) combination product was demonstrated, which is coated with CPP-KR12 in the form of nanoparticles on the surface of BGS. Self-entrapped AMP in silica nanoparticles is a safe and effective AMP delivery method that will be useful for developing a drug/device combination product for tissue regeneration.

Single-particle inductively coupled plasma mass spectrometry (spICP-MS) has been used for particle size measurement of diverse types of individual nanoparticles and micrometer-sized carbon-based particles, such as microplastics. However, its applicability to the measurement of micrometer-sized non-carbon-based particles such as silica (SiO2) is unclear. In this study, the applicability of spICP-MS to particle size measurement of non-porous/mesoporous SiO2 micro-spheres with a nominal diameter of 5.0 µm or smaller was investigated. Particle sizes of these microspheres were measured using both spICP-MS based on a conventional calibration approach using an ion standard solution and scanning electron microscopy (SEM) as a reference technique and the results were compared. The particle size distributions obtained using both techniques were in agreement within analytical uncertainty. The applicability of this technique to the detection of metal-containing protein-binding mesoporous SiO2 microspheres was also investigated. Bound iron (Fe)-containing proteins (i.e., lactoferrin and transferrin) of mesoporous SiO2 microspheres were detected using Fe as a presence marker for the proteins. Thus, spICP-MS is applicable to the particle size measurement of large-sized and non-porous/mesoporous SiO2 microspheres; it has considerable potential for element-based detection and qualification of bound proteins of mes-oporous SiO2 microspheres in a variety of applications.

The effect of zirconium modified with silica dioxide in the conductivity of modified nanocomposite membrane in proton exchange membrane fuel cells (PEMFCs) application. In this study silica-zirconia nanoparticles were successful synthesized by precipitation method. The surface area and surface morphology of Si-ZrO2 nanoparticles were observed under BET analysis, X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (HRTEM). SEM and XRD results show that silica was well incorporated into ZrO2 nanoparticles with the mixed shape of nanorods and nanosphere. HRTEM shows a crystallised small nanoparticle with average diameter about 5–8 nm. The element analysis (EDX) confirms the presence of silica and zirconia nanoparticles as well as oxygen on the surface. The addition of silica has impact on the surface area and pore size of Si-ZrO2 nanoparticles, with Si-ZrO2 nanoparticles having a higher surface area of 185 m2/g when calcinated at 600 °C. It was shown that the Si-ZrO2 can be used as an impregnating membrane to enhance the conductivity as observed by cyclic voltammetry (CV), with a rectangular shape that exhibiting the best capacitance behaviour.

Monodisperse and semi-facetted ultra-small templated mesoporous silica nanoparticles (US-MSN) of 20-25 nm were synthesized using a short-time hydrolysis of tetraethoxysilane (TEOS) at room temperature followed by a dilution for nucleation quenching. According to dynamic light scattering (DLS), a two-step pH adjustment was necessary for growth termination and colloidal stabilization. The pore size was controlled by cetyltrimethylammonium bromide (CTAB) and the tiny amount of neutral surfactant F127 was added for minimizing the coalescence between US-MSN and favoring the transition towards internal ordering. Flocculation eventually occured allowing to harvest a powder by centrifugation ( 60% silica yield after one month). The scanning transmission electron microscopy (STEM) and 3D high-resolution transmission electron microscopy (3D-HR-TEM) images revealed that the US-MSNs are partially ordered. The 2D FT transmorm images evidences the coexistance of four, five and sixfold patterns characterizing an “on-the-edge” crystallization step between amorphous raspberry and hexagonal pore array morphologies, typical of a protocrystalline state. Calcination preserved this state and yields a powder characterized by a packing developping a hierarchical porosity centered at 3.9 ± 0.2 (internal pores) and 68 ± 7 nm (packing voids) of high potential as support for separation and catalysis.

This study reports the preparation of silica and nano-fructosome encapsulated Candida antarctica lipase B particles (CalB@NF@SiO2) and demonstration of their enzymatic hydrolysis and acylation. CalB@NF@SiO2 particles were prepared as a function of TEOS concentration (3-100 mM). Their mean particle size was 185 nm by TEM. Enzymatic hydrolysis was performed to compare catalytic efficiencies of CalB@NF and CalB@NF@SiO2. Catalytic constants (Km, Vmax, and Kcat) of CalB@NF and CalB@NF@SiO2 were calculated with Michaelis-Menten equation and Line-weaver Burk plot. Optimal stability of CalB@NF@SiO2 was found at pH 8 and temperature of 35 ℃. Moreover, CalB@NF@SiO2 particles were reused for seven cycles to evaluate their reusability. In addition, enzymatic synthesis of benzyl benzoate was demonstrated by an acylation reaction with benzoic anhydride. The efficiency of CalB@NF@SiO2 for converting benzoic anhydride to benzyl benzoate by the acylation reaction was 97%, indicating that benzoic anhydride was almost completely converted to benzyl benzoate. Consequently, CalB@NF@SiO2 particles are better than CalB@NF particles for enzymatic synthesis. In addition, they are reusable with high stability at optimal pH and temperature.

Major progress in the field of regenerative medicine are expected from the design of artificial scaffolds that mimic both the structural and functional properties of the ECM. The bionanocomposites approach is particularly well fitted to meet this challenge as it can combine ECM-based matrices and colloidal carriers of biological cues that regulate cell behavior. Here we have prepared bionanocomposites under high magnetic field from Tilapia fish scale collagen and multifunctional silica nanoparticles (SiNPs). We show that scaffolding cues (collagen), multiple display of signaling peptides (SiNPs) and control over the global structuration (magnetic field) can be combined into a unique bionanocomposite for the engineering of biomaterials with improved cell performances.

Heavy metals are non-biodegradable and have a high toxicity effect to living things which makes their presence in the environment extremely dangerous. The method of handling heavy metals waste by photocatalysis techniques using TiO2/SiO2 composite showed a good performance in reducing harmful pollutants. In this study, SiO2 from Bengkulu beach sand was used as a support material for TiO2 photocatalyst to reduce Cr(VI) and Pb(II) concentrations. SiO2 was obtained through leaching techniques using NaOH as a solvent. The TiO2/SiO2 composite photocatalyst were synthesized using a solvothermal method at 130 °C and then characterized using XRD, FTIR, SEM and PSA. Based on the XRD diffractogram, the synthesized TiO2 showed the anatase structure while the SiO2 showed the amorphous structure. Ti-O-Si bond is defined in the IR spectra, which indicates that the relationship between TiO2 and SiO2 is a chemical interaction. The results of SEM and PSA characterizations show agglomerated spherical (round) particles with a mean particle size of 616.9 nm. The TiO2/SiO2 composite of 7:1 ratio showed the highest photocatalytic activity after 180 minutes of UV irradiation, with a concentration-decrease percentage of 93.77% and 93.55% for for Cr(VI) and Pb(II), respectively.

The present contribution is focused on the relation preparation – structure – optical properties of hybrid silica and zirconia powders containing Eu(III) complexes: [Eu(ntac)₃][pphendcn] and [Eu(phen)₂](NO₃)₃. Methods for functionalization of silica and zirconia microparticles, based on adsorption of 1,10-phenantroline and [Eu(ntac)₃][pphendcn], and doping with [Eu(phen)₂](NO₃)₃ nanoparticles are proposed to obtain of red emitting hybrid composites with quantum efficiency 20 – 50 %. The optical properties of rare earth ions incorporated in silica and zirconia composites are used to explore the site symmetry (D₂, C_2v or lower) of the Eu³⁺ optical centers in the hybrid composites. Quantum yields of the investigated sol-gel micropowders and quantification of their optical spectra are presented.

This paper summarizes some works exploiting the ate-type addition of electron-withdrawing monomers to hydrogenosiloxane groups so as to generate new silicone materials. Two types of monomers were oligomerized onto silicone backbones, namely unsaturated phosphonate and sulfone monomers. Phosphonated silicones are thermally more resistant than conventional silicones and can be transformed into amphiphilic polymers after selective ester hydrolysis. Sulfoned silicones generate solid supramolecular elastomers thanks to the strong pseudo-ionic interactions in play between sulfone groups. Rheology and modulated DSC show a solid/viscoelastic transition around 175°C, which allows using these thermoplastic materials on a larger scale than conventional silicone urea copolymers. These results open new avenues in the generation of silicone block- and grafted-copolymers with unique functionality and properties.

The practical application of a pH-responsive Nanoparticle Drug Delivery System (NDDS) in cancer treatment is often hampered by several issues such as the protection of therapeutic molecules from external stresses, inefficient targeted delivery, sustained drug release, and poor efficacy. This study presents an effective design strategy for the synthesis of a pH-sensitive controlled hydrophobic drug delivery method based on the formulation of chitosan (CS)-coated mesoporous silica nanoparticles (MSNs) through the sol-gel method, where hydrolysis takes place in the acidic medium followed by polycondensation of the hydrolyzed products. For this purpose, NH2 modified-MSNs were prepared by using tetraethyl orthosilicate (TEOS) as precursor and cetyltrimethylammonium bromide (CTAB) as a template, and 3-aminopropyltriethoxysilane (APTES) for amine modification, followed by hydrophobic drug loading and CS coating of various concentrations. Camptothecin (CPT) was used as a model drug. Fabricated monodispersed functionalized nanoparticles had sizes ranging from 200nm to 245nm with an encapsulation efficiency as high as 90%. The highest encapsulation efficiency was found for 1% CS coating, which released 50% drug in 120h at pH 6.4 and 20% at pH 7.4 respectively. These nanoformulations exhibited pH-responsive release patterns of CPT under two different pH values (pH=7.4 and pH=6.4). These results contribute to the optimization of NDDS, with potential implications for nanoformulations designed for controlled and sustained drug release particularly to tumors without affecting healthy cells owing to differences in the pH of the tumor microenvironment and the normal physiological environment of cells.

This study aims to formulate binary cementitious systems containing silica fume (SF) and micro quartz (MQ) to improve cementitious concrete's durability and mechanical properties. In this investigation, we examined the effects of different essential variables, such as the level of SF and MQ replacement and the ratio of the water-binder (w/b). In this study, the w/b ratios were 0.25, 0.3, 0.35, and 0.4. Replacement levels for SF were 8, 10, and 12%, while replacement levels for MQ were 5, 8, 10, 15, 25, and 35%. The porosity and permeability decreased with an increase in replacement levels, regardless of the type of fine material used or the amount of replacement. Meanwhile, the strength increased markedly with SF replacement, reaching its maximum MQ of 25% at the SF level. The strength of the SF mixing was the highest in all mixes, and it remained the highest until 15% of MQ was replaced. The ultrafine size of MQ particles contributes to the improvement of compressive strength, porosity, and permeability in a similar way to SF particles, despite their high crystalline structure. Furthermore, in this study, analysis of variance (ANOVA) was employed to verify the influence of each variable on the studied response.

The one pot hydrogenolysis/hydrogenation reaction of maltose to 2 moles of sorbitol has been carried out over different supported Cu catalysts in water at 180°C and 40 bar of H2. Only the catalysts supported on silicas were found to be effective in this reaction giving up to 86% yield in the desired product while the bare supports and the catalysts supported on alumina or silica alumina gave messy reactions. The peculiar activity of the two Cu/Silica systems tested was ascribed to high metal dispersion and suitable polarity of the catalyst surface. The reduced catalyst, exposing metallic Cu particles on the surface, showed unusual stability in the presence of water as a solvent and could be reused several times without any treatment.

Nanomaterials exhibit novel properties and profound attributes as an additive in asphalt binder modification. However, the application of nano-silica in asphalt binders and mixture modification is still limited and further research is required. Along these lines, in this work, nano-silica with a content from 2% to 8% and an increment of 2% were utilized in modifying the bitumen binder type C320, which is considered the most conventional type of bitumen used in Western Australia road asphalt mixtures. Various tests were performed to assess their properties including dynamic shear rheometer, penetration, softening point, and multiple stress creep recovery (MSCR) test. The extracted results revealed an increase in the strength and stiffness properties by lowering the penetration, improving the softening point, and increasing the complex shear modulus of all nano-silica modified bitumen samples. Interestingly, a relatively big content of nano-silica leads to a higher rutting resistance. Nevertheless, the rutting resistance was affected by the size of the nano-silica coated with the silane coupling agent. The ideal sample of nano-silica modified C320 was determined as NS-15nm (NS-A), which can improve the rutting resistance. Nevertheless, the rutting resistance of the modified asphalt mixtures needs to be further investigated in the future to elaborate on the impact of nano-silica as modified binders on the mechanical properties of Australian asphalt mixtures.

Because of their low cost and easy production silica nanoparticles (NPs) are amply used in multiple manufactures as anti-caking, densifying and hydrophobic agents. However, this has increased the exposure levels of the general population and has raised concerns about possible toxicity of this nanomaterial. NPs are known to affect the function of the airway epithelium, but the biochemical pathways targeted by these particles remain largely unknown. Here we investigated the effects of NPs on the responses of cultured human bronchial epithelial (16HBE) cells to the damage-associated molecular pattern ATP, using fluorometric measurements of intracellular Ca2+ concentration. Upon stimulation with extracellular ATP these cells displayed a concentration-dependent increase in intracellular Ca2+, which was mediated by release from intracellular stores. Silica NPs inhibited the Ca2+ responses to ATP within minutes of application and at low micromolar concentrations, which are significantly faster and more potent than those previously reported for the induction of cellular toxicity and pro-inflammatory responses. NPs-induced inhibition appeared to be independent from the increase in intracellular Ca2+ they produce, and via a non-competitive mechanism. These findings suggest that NPs reduce the ability of airway epithelial cells to mount ATP-dependent protective responses such as the increase in mucociliary clearance and cough.

The article describes synthesis of aminoorgano-functionalized silica as a perspective material for catalysis application. The amino groups have electron donor properties valuable for metal chemical state of palladium. So presence of electron donor groups is important for increasing of catalysts stability. The research is devoted to investigation of silica amino-modified support influence on activity and stability of palladium species in 4-nitroaniline hydrogenation process. A series of catalysts with different supports such as SiO2, SiO2-C3H6-NH2 (amino-functionalized silica), γ-Al2O3 and activated carbon were studied. The catalytic activity was studied in the hydrogenation of 4-nitroaniline to 1,4-phenylenediamine. The catalysts were characterized by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and pulse chemisorption of hydrogen. The 5 wt. % Pd/SiO2-C3H6-NH2 catalyst exhibited the highest catalytic activity for 4-nitroaniline hydrogenation with 100% conversion and 99% selectivity with respect to 1,4-phenylenediamine.

The purpose of this scoping review was to identify gaps in the literature and summarize findings from studies examining the use of silicon-, silica-, and silicate-based toothpastes for the remineralization and repair of mineralized tooth tissues. A 10-year literature search was conducted using PubMed and Scopus, adhering to PRISMA 2020 guidelines. A total of 331 studies were initially identified, with 56 full-text review articles. After selecting the manuscripts, 27 studies were qualitatively analyzed by four reviewers, focusing on the results of both in vivo and in vitro methods. The findings suggest that toothpastes containing silicon, silica, and silicate demonstrate promising results for remineralization and enamel repair, with evidence of mineral layer formation and/or deep enamel surface remineralization under various conditions. Additionally, the use of these toothpastes can lead to the obliteration of dentinal tubules within a few days. The results collectively support the efficacy of these toothpastes in enamel repair. Most of the clinical studies focused on dentine hypersensitivity, followed by white spot lesions. In conclusion, silicon-, silica-, and silicate-based toothpastes (bioactive-Si-toothpastes) can be considered effective based mostly on laboratory studies. There remains a need for more in vivo research studies on enamel and dentin mineral repair. Existing studies provide strong evidence that these technologies can reduce dentin hypersensitivity and promote enamel-dentin repair.

Fused silica glass is a material with outstanding mechanical, thermal and optical properties. Being a brittle material, it is challenging to shape. In the last decade, the manufacturing of monolithic flexible mechanisms in fused silica has evolved with the femtosecond laser-assisted etching process. However, instrumenting those structures is demanding. To address this obstacle, this article proposes to inscribe a Bragg Grating sensor inside a flexure and interface it with an optical fibre to record the strain using a spectrum analyzer. The strain sensitivity of this Bragg Grating sensor is characterized at 1.2 pm/μϵ (1 μϵ = 1 microstrain). Among other applications, deformation sensing can be used to record a force. Its use as a micro-force sensor is estimated. The sensor resolution is limited by our recording equipment to 30 μN over a measurement range above 10 mN. This technology can offer opportunities for surgery applications or others where precision and stability in harsh environments are required.

In this work, alkylammonium-functionalized hollow mesoporous silica as nonocarrier of drugs was synthesized to realize enhanced cancer therapy by pH stimuli for sustained drug release. First, functionalized hollow mesoporous silica nanoparticles (Hollow MSNs) were synthesized using dodecyl dimethyl(3-sulfopropyl)ammonium hydroxide (DDAPS), sodium dodecyl sulfate (SDS), and triethanolamine as structure-directing agents, and tetraethyl orthosilicate (TEOS) and N-trimethoxysilypropyl-N,N,N-trimethylammonium chloride (TMAPS) as silica sources under basic condition via the sol-gel process. The structure and morphology of the alkylammonium-functionalized hollow mesoporous silica nanoparticles (Hollow MSN-N+CH3) were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption analysis, and Fourier-transform infrared (FT-IR) spectroscopy. The functionalized hollow MSNs had a particle size of about 450 nm and a shell thickness of about 60 nm with uniform size. The nanoparticle had a surface area of 408 m2g-1, pore volume of 0.8 cm3g-1 and a uniform pore diameter of 45.9 Å. In the cancer cell viability test with MCF-7 cell, fludarabine-incorporated and alkylammonium-functionalized hollow mesoporous silica nanoparticles (Flu/Hollow MSN-N+CH3) showed excellent cancer cell death comparable with pure fludarabine drug with the controlled drug release by pH stimuli. It is considered that our current materials have the potential applicability as pH-responsive nanocarriers in the field of cancer therapy.

The purpose of this study is to identify the steps involved in fabricating silica/chitosan composite membranes and their suitability in fuel cell application. It also intends to identify the physical characteristics of chitosan composite membranes, including their degree of water absorption, proton conductivity, methanol permeability, and functional groups. In this investigation, composite membranes were fabricated using the solution casting method with chitosan content of 5 g and silica variations dosage of 2% and 4% while stirring at a constant speed for 2h. According to the findings, the analysis of composite membranes produced chitosan membranes that were successfully modified with silica. The optimum membrane was found to be 4% s-SiO2 from the Sol-gel method with composite membrane's optimal condition of 0.234 cm/s proton conductivity, water uptake of 56.21%, and reduced methanol permeability of 0.99 × 10 -7 cm2/s in the first 30 minutes and 3.31 × 10-7 in the last 150 minutes. Maintaining lower water uptake capacity at higher silica content is still a challenge that needs to be addressed. However, the fabricated membranes showed exceptional results in terms of proton conductivity and methanol permeability.

Benign design of alkali-activated slag/FA geopolymer paste has intriguing increasing attention for optimizing its service performance. Therefore, the replacement of fly ash (FA) with 10 wt% silica fume (SF) is investigated by mechanical strength after freeze-thawing cycles and microstructure characterization. The results show that an appropriate dosage (30 wt%) of slag is necessary to attain alkali-activated slag/FA geopolymer paste with excellent mechanical performance, and the SF/slag/FA (SF: slag: FA= 10:30:60, wt%) geopolymer paste exerts the compressive and flexural strength of 95.2 and 3.2 MPa, respectively. Meanwhile, the doped 10 wt% SF facilitates the propagation of (N, C)-A–S–H chains, rather than the formation of C-S-H gels, evidenced by the absent exothermic peak at about 861oC from the differential scanning calorimetry (DSC) curves, leading to the increases in the pores volume with a pore diameter<20 nm and tortuosity by mercury intrusion porosimeter (MIP) results, corresponding to an improved freezing-thawing resistance with the residual compressive strength of 52.8 MPa and the weight loss of 10.5% after 300 freeze-thawing cycles. It explores a cost-effective and benign facile approach to designing heating curing-free alkali-activated slag/FA geopolymer paste with good freezing-thawing resistance.

The fireproof design of geopolymer has intriguing increasing attention by adjusting multi-component metallurgical solid wastes, due to its low-carbon emission, cost-effectiveness, and environmental conservation. Herein, the effects of silica fume (SF) on the microstructure and mechanical properties of alkali-activated slag/FA (fly ash) pastes subjected to elevated temperatures (150, 500, 850, and 1200℃) are investigated, to clarify the fact that whether or not the SF generates positive roles in mechanical strength of slag/FA (slag: FA=30:70, wt.%) geopolymers during building fires. The results show that the replacement of FA with 10 wt% SF (silica fume) promotes the increasing pore volume with a diameter of 0.2~3 μm, leading to an increase in the compressive or flexural strength below 850℃, “right shifts” of the endothermic peak, appearing uniform and compact fracture surfaces. Meanwhile, the gehlenite and labradorite generate after exposure above 850℃. While the bloating effect of the SF-containing sample occurs at 1200℃, leading to a greater deformation, due to the further restructuring of the amorphous geopolymer chain N-A-S-H or N-(Ca)-A-S-H composed from the [SiO4]4− and [AlO4]5−. It explores an effective approach for improving geopolymer’s fireproof performance by adjusting the solid-waste formulation.

Supplementary cementitious materials (SCMs) are increasingly used in precast concrete industry to enhance concrete strength and durability. SCMs of large market share in precast concrete in-dustry include silica fume, also known as micro-silica and class C fly ash. The main objective of this research is to develop non-proprietary high strength concrete mixes for precast/prestressed concrete industry. Two SCMs are used simultaneously in partial replacement of portland cement to develop ternary mixes. Class c fly ash and silica fume incorporation in the mix design, in ad-dition to low water-to-powder ratio resulted in the successful development of high strength mixes with minimum 24-hour strength in excess of 70 MPa and a final compressive strength ex-ceeding 100 MPa at 28 days. Mechanical properties testing of developed concrete mixes showed that SCMs incorporation resulted in increased values for hardened concrete modulus of elasticity (MoE) and modulus of rupture (MoR). The enhanced concrete properties, mainly high early strength, are highly required in precast concrete industry as it allows for increased productivity of precast facilities and the possibility of pouring high strength slender sections for prestressed concrete applications

Expansive soil shows dual swell-shrink which is not suitable for the construction. Several mitigating techniques exist to counteract the problem promulgate by expansive clayey soils. This paper explored the penitential mecho-chemical reinforcement of expansive clayey soil to mitigate the effect of upward swelling pressure and heave. The polypropylene fiber is randomly distributed in the soil for mechanical stabilization, and the industrial residual silica fume is used as a chemical stabilizer. The experimental analysis is made in three phases which involved the tests on mechanical reinforced expansive soil using randomly distributed polypropylene fibers with different percentages (0.25%, 0.50%, and 1.00%), and 12mm length. The second phase of experiments carried out on chemical stabilized expansive soil with different percentages (2%, 4% and 8%) of silica and next phase of the experimental focused in the combination of mecho-chemical stabilization of the expansive soil with different combination of silica (i.e., 2%, 4% and 8%) and polypropylene fibers (i.e., 0.25%, 0.50% and 1.00%). Maximum dry density (MDD), optimum moisture content (OMC), liquid limit (LL), plastic limit (PL), plastic index (PI) grain size, and constant volume swelling pressure test were performed on unreinforced and reinforced expansive soil to investigate the effect of polypropylene fiber and silica fume on the engineering properties of expansive clayey soil. The experimental results illustrate that the inclusion of polypropylene fiber has a significant effect on the upward swelling pressure and expansion property of expansive soil. The reduction in the upward swelling pressure and expansion is a function of fiber content. These results also indicated that the use of silica fume caused a reduction in upward swelling potential, and its effect was considerably more than the influence of fiber.

Highly colloidal Eu-doped Gd2O3 nanoparticles(core-NPs) were synthesized by thermal decomposition via weak base at low temperature (150oC), subsequently, silica layers were deposited to increased colloidal stability, solubility, biocompatibility and no-toxicity at the environmental condition. XRD results indicate the highly purified, crystalline, single phase cubic phase Gd2O3 nanocrystals. TEM image shows the mesoporous thick silica layer was effectively coated over the core nanocrystals, which have irregular size with nearly spherical shape and a mean grain size is about 10-30 nm. Absorption spectra and zeta potential results in aqueous media revealed that solubility, colloidal stability, and biocompatibility character was enhanced from core to core-shell structure because of silica layer surface encapsulation. The samples demonstrate excellent photoluminescence properties (dominant emission 5D0→7F2 transition in red region at 610 nm) indicated the advantage to use in optical bio-detection and bio-labeling etc. The photoluminescence intensity of the silica shell modified core/shell nanoparticles were suppressed relatively core-nanoparticles, it indicates the multi-photon relaxation pathways arising from the surface coated high vibrational energy molecules of the silanol groups. The core/nSiO2/mSiO2 nanocrystals display strong emission (5D0→7F2) transition along with excellent solubility and biocompatibility, which may find promising applications in photonic based biomedical applications.

ω-Transaminases have been immobilized on macrocellular silica monoliths and used as heterogeneous biocatalysts in a continuous flow mode enantioselective transamination reaction. The support was prepared by a sol-gel method based on emulsion templating. The enzyme was immobilized on the structured silica monoliths both by adsorption, and by covalent grafting using amino-functionalized silica monoliths and glutaraldehyde as a coupling agent. A simple reactor set-up based on the use of a heat-shrinkable Teflon tube is presented and successfully used for the continuous flow kinetic resolution of a chiral amine, 4-bromo-α-methylbenzylamine. The porous structure of the supports ensures effective mass transfer and the reactor works in the plug flow regime without preferential flow paths. When immobilized in the monolith and used in the flow reactor, transaminases retain their activity and their enantioselectivity. The solid biocatalyst is also shown to be stable both on stream and during storage. These essential features pave the way to the successful development of an environmentally friendly process for chiral amines production.

New chemicals including nanomaterials are being created and spread at high speed. In the E.U., REACH compliance imposes to manufacturers some tests but they are limited. Often, they cannot detect anything if the cells or organisms are able to overcome the toxic effect at the macroscopic level, preventing the suspicion of a potential long-term effect. Concerning bacteria that are essential for ecosystems and human health (microbiota), they are often considered as a whole in a consortium and only global parameters are measured. To overcome these limitations, we performed a study on the essential soil bacterium Bacillus subtilis. Two types of biofilm that are closer to its natural growth mode (particularly around plant roots) than the usual liquid type culture have been assayed: pellicle biofilm and swarming. We then used the power of shotgun proteomics to analyze in details these two somehow similar modes of cultures. Several physiological and metabolic patterns including proteins implicated in sporulation have shown significant differences. The effect of two types of nanoparticles (silicon and cerium oxide nanoparticles) has then been studied in the same way. This allowed us to investigate in details the response of the bacteria and focus on the differences observed depending on the biofilm type. This clearly highlighted the importance of testing several growth conditions and pinpointed the power of proteomics.

For centuries, humans have relied on natural products to prevent and treat numerous health issues. However, biologically active compounds from natural sources, such as polyphenols, face significant challenges, including low solubility, rapid metabolism, and instability, which hinder their effectiveness. Advances in science and nanotechnology have provided solutions to overcoming these problems through the use of porous silica materials. These materials possess unique properties, such as a high specific surface area, adjustable particle and pore sizes, and a surface that can be easily and selectively modified. In this review, we summarize and discuss findings on how the pore and particle size, structure, and surface modification of silica materials influence the preparation of efficient delivery systems for biologically active polyphenols from natural sources. The available data demonstrate how parameters such as adsorption capacity, release and antioxidant properties, bioavailability, solubility, stability, etc. of the studied delivery systems could be affected by the structural and chemical characteristics of the porous silica carriers.

Hydrogels can offer many opportunities for drug delivery strategies. They can be used on their own or their benefits can be further exploited in combination with other nanocarriers. Intelligent hydrogels that react to changes in the surrounding environment can be utilized as gatekeepers and provide sustained on demand drug release. In this study, a hybrid nanosystem for tempera-ture and pH sensitive delivery was prepared from MCM-41 nanoparticles grafted with newly synthesized thermosensitive hydrogel (MCM-41/AA-g-PnVCL). The initial particles were chemi-cally modified by carboxyl groups attachment. Later, they were grafted with agar (AA) and vi-nylcaprolactam (VCL) by free radical polymerization. Doxorubicin was applied as a model hy-drophilic chemotherapeutic drug. The successful formulation was confirmed by FT-IR and TGA. Transmission electron microscopy and dynamic light scattering analysis showed small particles with negative zeta potential. Their release behaviour was investigated in vitro in different pH media and at different temperatures. At tumor simulating conditions (40ºC and pH 4.0) doxoru-bicin was almost completely released within 72 hours. The biocompatibility of the proposed na-noparticles was demonstrated by in vitro haemolysis assay. These results suggest the possible parenteral application of the newly prepared hydrogel-functionalized mesoporous silica nanopar-ticles for temperature-sensitive and pH-triggered drug delivery at the tumor site.

The risk of lung exposure to silica nanoparticles (SiNPs) and related lung inflammatory injury is increasing with the wide application of SiNPs in a variety of industries. A growing body of research has revealed that cyclooxygenase (COX)-2/ prostaglandin E2 (PGE2) up-regulated by SiNPs toxicity has a role during pulmonary inflammation. The detailed mechanisms underlying SiNPs-induced COX-2 expression and PGE2 synthesis remain unknown. The present study aims to dissect the molecular components involved in COX-2/PGE2 up-regulated by SiNPs in human pulmonary alveolar epithelial cells (HPAEpiCs) which are one of the major targets while SiNPs are inhaled. In the present study, we demonstrated that SiNPs induced COX-2 expression and PGE2 release, which were inhibited by pretreatment with a reactive oxygen species (ROS) scavenger (edaravone) or the inhibitors of proline-rich tyrosine kinase 2 (Pyk2, PF-431396), epidermal growth factor receptor (EGFR, AG1478), phosphatidylinositol 3‑kinase (PI3K, LY294002), protein kinase B (Akt, Akt inhibitor VIII), p38 mitogen-activated protein kinase (MAPK) (p38 MAPK inhibitor VIII), c-Jun N-terminal kinases (JNK)1/2 (SP600125), Forkhead Box O1 (FoxO1, AS1842856), and activator protein 1 (AP-1, Tanshinone IIA). In addition, we also found that SiNPs induced ROS-dependent Pyk2, EGFR, Akt, p38 MAPK, and JNK1/2 activation in these cells. These signaling pathways induced by SiNPs could further cause c-Jun and FoxO1 activation and translocation from the cytosol to the nucleus. AP-1 and FoxO1 activation could increase COX-2 and PGE2 levels induced by SiNPs. Finally, the COX-2/PGE2 axis might promote the inflammatory responses in HPAEpiCs. In conclusion, we suggested that SiNPs induced COX-2 expression accompanied by PGE2 synthesis mediated via ROS/Pyk2/EGFR/PI3K/Akt/p38 MAPK- and JNK1/2-dependent FoxO1 and AP-1 activation in HPAEpiCs.

The objective of this work is to study the physical and mechanical behavior of concrete with the addition of 0.5% and 1.0% of coconut fibers subjected to two chemical treatments in order to reduce their degradation and optimize their use in the elaboration of concrete specimens, which must comply with the standards of the American Society for Testing of Materials (ASTM), the American Concrete Institute (ACI) and the Instituto Ecuatoriano de Normalización (INEN). The coconut fibers were obtained from the raw material by hand and cut to a length of 4 cm. Subsequently, the coconut fibers were subjected to two chemical treatments: The first treatment is the immersion of the coconut fibers in 4% sodium hydroxide (NaOH) solution and the second treatment, the coconut fibers were immersed in gum arabic to consequently coat them with silica fume. A particular dosage was carried out with a proportion of 0.5% and 1.0% volume of coconut fiber for the two chemical treatments, replacing the volume of coarse aggregate. Simple concrete joists were made without fiber and with the post-treatment coconut fibers, which were subjected to flexural tests. The results indicated that the best chemical treatment is sodium hydroxide with a concentration of 4% and 1.0% coconut fiber for strengths of 210 kg/cm² and 240 kg/cm². In general, the joists with coconut fiber treated with sodium hydroxide outperformed the fibers treated with gum arabic and silica fume.

Recycling of metallurgical solid waste has intriguing increasing attention for fabricating cementitious materials, due to its low-carbon emission, cost-effectiveness, and environmental conservation. Herein, the effects of silica fume (SF) on the microstructure and mechanical properties of alkali-activated slag/FA (fly ash) pastes subjected to elevated temperatures (150, 500, 850, and 1200℃) are investigated, to clarify the fact that whether or not the SF generates positive roles in mechanical properties of slag/FA geopolymers. The results show that the replacement with 10 wt% SF (silica fume) promotes the increasing pore volume with a diameter of 0.2~3 μm at room temperature, leading to an increase in the compressive or flexural strength, “right shifts” of endothermic peak and the initial-final temperature of mass loss, presenting a denser and compact fracture surface. Meanwhile, the mineral phase of gehlenite and labradorite emerges after exposure above 850℃ from the XRD results. Furthermore, the bloating effect of the incorporated SF occurs due to the formation of a liquid phase altogether with the amorphous silicates after exposure to 1200℃, leading to a greater deformation and enhancement of restructuring involved in the [SiO4]4− and [AlO4]5−. It explores an effective recycling approach for fabricating paste binders using metallurgical solid wastes.

In this work, polyacrylic acid-functionalized MCM-41 was synthesized, which was further interacted with calcium ions, to realize enhanced pH-responsive nanocarrier for sustained drug release. First, mesoporous silica nanoparticles (MSNs) were prepared by the sol-gel method. Afterward, (3-trimethoxysilyl)propyl methacrylate (TMSPM) modified surface was prepared by using the post-grafting method, then polymerization of acrylic acid was proceeded. After adding calcium chloride solution, polyacrylic acid-functionalized MSNs with calcium-carboxyl ionic bonds in the polymeric layer, which can prevent the cargo from leaking out of the mesopore, were prepared. The structure and morphology of the modified nanoparticles (PAA-MSNs) were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and N2 adsorption-desorption analysis, etc. The controlled release of guest molecules was studied by using 5-fluorouracil (5-FU). The drug molecules-incorporated nanoparticles showed different releasing rates under different pH conditions. It is considered that our current materials have the potential as pH-responsive targeted nanocarriers in the field of medical treatment.

Background: Work experience is a key factor that influences safety awareness among workers. This study investigated the influence of work experience on the level of awareness on adverse health effects of silica dust exposure among stone quarry workers in Ghana while controlling for theoretically relevant compositional and contextual factors, evaluated the magnitude and order of association between the predictors and the predicted variable. Method: A cross-sectional survey data of 524 randomly selected stone quarry workers were subjected to multivariate statistical analyses. Results: Stone quarry workers who had 6 to10 years and more than 10 years of work experience were 48% (OR = 1.475, P = 0.021) and 82% (OR = 1.816, P = 0.003) respectively more likely to be aware of the adverse health effects of silica dust exposure compared to their counterparts who had 1 to 5 years work experience. Workers who had secondary or higher education were 32% (OR = 1.320, P = 0.036) more likely to be aware of the adverse health effects of silica dust exposure compared to their counterparts who had no education. Conclusion: These findings provide relevant information for managers and policymakers to plan and maximize awareness on silica dust health hazards among silica exposed workers.

Nanoparticles (NPs) have various applications in medicine, cosmetics, optics, catalysis, environmental purification, and other areas nowadays. With an increasing annual production of NPs, the risks of their harmful influence to the environment and human health is rising. Currently, our knowledge about the mechanisms of interaction between NPs and living organisms is limited. Additionally, poor understanding of how physical and chemical characteristic and different conditions influence the toxicity of NPs restrict our attempts to develop the standards and regulations which might allow us to maintain the safe living conditions. The marine species and their habitat environment are under continuous stress due to anthropogenic activities which result in the appearance of NPs in the aquatic environment. Our study aimed to evaluate and compare biochemical effects caused by the influence of different types of carbon nanotubes, carbon nanofibers, and silica nanotubes on four marine microalgae species. We have evaluated the changes in growth-rate, esterase activity, membrane polarization, and size changes of microalgae cells using flow cytometry method. Our results demonstrated that toxic effects caused by the carbon nanotubes strongly correlated with the content of heavy metal impurities in the NPs. More hydrophobic carbon NPs with less ordered structure had a higher impact on the red microalgae P. purpureum because of higher adherence between the particles and mucous covering of the algae; silica NPs caused significant inhibition of microalgae growth-rate predominantly produced by mechanical influence.

Thermal energy storage (TES) is a key technology to enhance the efficiency of energy systems as well as to increase the share of renewable energies. In this context, the present paper reports a literature review of the recent advancement in the field of adsorption TES systems. After a first introduction about different heat storage technologies, the adsorption TES working principle is explained and compared to the other technologies. Subsequently, promising features and critical issues at material, component and system levels are deeply analyzed and the ongoing activities to make this technology ready for marketing are introduced.

This study investigates the necessity of particle asymmetry for self-propulsion in nanomotors. While conventional wisdom posits that asymmetric designs are crucial for generating phoretic forces or localized bubble propulsion, recent research suggests that symmetrical particles may also exhibit motility. To address this debate, we developed a robust workflow for synthesizing gold grafted silica nanoparticles with precise control over size and shape, enabling the direct comparison of their motile behavior by dynamic light scattering and particle tracking velocimetry. Our results indicate that the inherent asymmetry generated during isotropic gold nanoparticle deposition onto silica surfaces may enable particle motility.

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.

This study assesses the performance of calcium aluminate (CAC) and calcium sulfoaluminate (CSA) cement mortars, particularly when blended with fly ash (FA) and limestone powder (LP). The effects of incorporating 20% FA, 15% LP, and their combination (FA 20% and LP 15%), using a water-binder ratio of 0.40 were explored. The study meticulously evaluates the performance of the mortar mixtures in terms of setting time and mechanical properties, including compressive strength, flexural strength, and direct tensile strength. Additionally, the study investigated the alkali-silica reaction (ASR) and autogenous shrinkage. Advanced analytical methods such as X-ray diffraction (XRD), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM) were employed to further understand the microstructural changes. The study reveals a significant correlation between compressive, flexural, and direct tensile strengths of the mortar mixtures. Notably, CSA and CAC mortar mixtures with SCMs showed an ASR value lower than the recommended 0.10%, while the autogenous shrinkage for both CAC and CSA mixtures was less compared to Ordinary Portland Cement (OPC). The influence of SCMs, though not substantial, was clearly observed. TGA results corroborated the phases identified in XRD and those observed in SEM, through the thermal decomposition of the phases present in the mixtures. This study contributes valuable insights into the use of SCMs in improving the performance and sustainability of CAC and CSA cement mortars.

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.

Gold nanoclusters (AuNCs) with fluorescence in the Near Infrared (NIR) by both one- and two-photon electronic excitation were incorporated in mesoporous silica nanoparticles (MSNs) using a novel one-pot synthesis procedure where the condensation polymerization of alkoxysilane monomers in the presence of the AuNCs and a surfactant produce hybrid MSNs of 49 nm diameter. This method was further developed to prepare 30 nm diameter nanocomposite particles with simultaneous NIR fluorescence and superparamagnetic properties, with a core composed of superparamagnetic manganese ferrite nanoparticles (MnFe2O4) coated with a thin silica layer, and a shell of mesoporous silica decorated with AuNCs. The nanocomposite particles feature NIR-photoluminescence with 0.6% quantum yield and large Stokes shift (290 nm), and superparamagnetic response at 300 K, with a saturation magnetization of 13.4 emu g-1. The conjugation of NIR photoluminescence and superparamagnetic properties in the biocompatible nanocomposite has high potential for application in multimodal bioimaging.

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.

Antimicrobial resistance (AMR), a consequence of the ability of microorganisms, especially bacteria, to develop resistance against conventional antibiotics hampering the treatment of common infections, is recognized as one of the most imperative health threats of this century. Antibacterial photodynamic therapy (aPDT) has emerged as a promising alternative strategy, utilizing photo-sensitizers activated by light to generate reactive oxygen species (ROS) that kill pathogens without inducing resistance. In this work, we synthesized silica nanoparticles of different sizes (20 nm, 80 nm, and 250 nm) functionalized with the photosensitizer Rose Bengal (RB) and a gluconamide ligand, which targets Gram-negative bacteria, to assess their potential in aPDT. Comprehensive characterization, including dynamic light scattering (DLS) and photophysical analysis, confirmed the stability and effective singlet oxygen production of the functionalized nanoparticles. RB loading was size-dependent, decreasing with increasing nanoparticle diameter. Consequently, the largest nanoparticles (250 nm) displayed insufficient RB surface density for effective aPDT, while the smallest (20 nm) and intermediate (80 nm) particles were more promising. Bacterial assays in E. coli revealed minimal dark toxicity and significant light-activated phototoxicity for the RB-loaded nanoparticles. The addition of gluconamide notably enhanced phototoxic activity, particularly in the smallest nanoparticles (RB-G-20@SiNP), which demonstrated the highest photo-toxicity-to-cytotoxicity ratio. These findings indicate that small, gluconamide-functionalized silica nanoparticles are highly effective for targeted aPDT, offering a robust strategy to combat AMR.

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.

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%.

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.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by widespread inflammation and multi-organ damage. Toll-like receptor 7 (TLR-7) and autophagy have been implicated in SLE pathogenesis. Rice husk silica liquid (RHSL) has shown potential for modulating inflammatory responses, but its effects on SLE have not been thoroughly investigated. This study aims to evaluate the impact of RHSL on immune responses and autophagy in an in vitro model of SLE, focusing on its effects on TLR-7 signaling, cytokine production, and autophagy modulation. RAW264.7 cells and human peripheral blood mononuclear cells (PBMCs) from healthy donors and SLE patients were used. Cells were stimulated with LPS or TLR-7 agonists and treated with RHSL. Cell viability was assessed, and cytokine levels (TNF-α and IL-6) were measured by ELISA. Autophagy-related proteins (LC3II, ATG5-ATG12) were analyzed by Western blotting. The effect of autophagy inhibition was studied using 3-methyladenine (3-MA). RHSL did not affect cell viability but significantly reduced TNF-α production in LPS- and TLR-7 agonist-stimulated RAW264.7 cells and PBMCs. RHSL enhanced autophagy, as evidenced by increased LC3II and ATG5-ATG12 conjugation in both RAW264.7 cells and SLE patient-derived PBMCs. The reduction in TNF-α production by RHSL was attenuated by 3-MA, indicating that autophagy plays a role in this process. RHSL also inhibited the translocation of phosphorylated NF-κB into the nucleus, suggesting a mechanism for its anti-inflammatory effects. RHSL exhibits potential as an immunomodulatory agent in SLE by enhancing autophagy and modulating TLR-7 signaling pathways. These findings suggest that RHSL could offer therapeutic benefits for managing inflammatory responses in SLE and warrant further investigation into its clinical applications.

in order to enhance the separation performance and to reduce the heat loss of the transmembrane for membrane distillation, the thermal efficiency and hydrophobicity of the membrane distillation should be simultaneously enhanced. In this work, a PVDF/PET hydrophobic/hydrophilic membrane is prepared by non-solvent phase inducing method. Nanosized silica aerogel (SiAG) with high porosity is added to the composite membranes. The modifying effects and operating conditions on permeate flux and thermal efficiency in direct contact membrane distillation (DCMD) are investigated. Furthermore, the latent heat of vaporization and the heat transfer across the membranes are compared for SiAG addition, which indicates that the composite PVDF@SiAG/PET membranes display a great potential for distillation-separation application with high heat efficiency.

BODIPY dyes have recently raised attention as potential photosensitizers. In this work, commercial and novel photosensitizers (PSs) based on BODIPY chromophores (haloBODIPYs and orthogonal dimers strategically designed with intense bands in the blue, green or red region of the Visible spectra and high singlet oxygen production) were covalently linked to mesoporous silica nanoparticles (MSNs) further functionalized with PEG and folic acid (FA). MSNs of approximately 50 nm in size with different functional groups were synthesized to allow multiple alternatives of PS-PEG-FA decoration of their external surface. Different combinations varying the type of PS (commercial Rose Bengal, Thionine and Chlorine e6 or custom-made BODIPY-based), the linkage design and the length of PEG are detailed. All the nanosystems were physicochemically characterized (morphology, diameter, size distribution and PS loaded amount) and photophysically studied (absorption capacity, fluorescence efficiency, and singlet oxygen production) in suspension. For the most promising PS-PEG-FA silica nanoplatforms, the biocompatibility in dark conditions and the phototoxicity under suitable irradiation wavelengths (blue, green, or red) at regulated light doses (10-15 J/cm2) were compared with PSs free in solution in HeLa cells in vitro.

Chronic exposure of workers to powder containing crystalline silica (SiO₂) can lead to chronic lung diseases (lung cancer, silicosis, etc.). The aim of the study was to evaluate the exposure of Greek construction workers to SiO₂ and describe their pulmonary function. The study involved 86 outdoor and underground workers. Medical and professional history was obtained, and breath samples were collected at morning hours through a mask for the determination of SiO₂ levels. Pulmonary function tests, radiological examination and evaluation of radiographs were, also performed. During the examination of the pulmonary function, the majority of the workers were within normal range (61.4%) while the rest were diagnosed with mild (26.5%) and more severe impairment (7.2%). Working conditions (underground-outdoor) were statistically significantly related to the categorization of pulmonary function (p = 0.038). During radiological examination, the type of working conditions (underground-outdoor) were statistically significantly related to the categorization of these findings (p = 0.044). Of the 69 employees, 52 did not present findings (75.4%) and five (5) were diagnosed with findings specific to occupational diseases (7.2%). The environmental exposure to RCS (Respirable crystalline silica) was detected at 0,0125 mg/ m³ in the workplace, which is not beyond the legal limits. Underground workers with more than 15 years of exposure to SiO₂ are more likely to present chronic silicosis compared to the workers of outdoor activities.

Flavonoids, polyphenols with anti-oxidative activity have high potential as novel therapeutics for neurodegenerative disease, but their applicability is rendered by their poor water solubility and chemical instability under physiological conditions. In this study, this is overcome by delivering flavonoids to model cell membranes (unsaturated DOPC) using prepared and characterized biodegradable mesoporous silica nanoparticles, MSNs. Quercetin, myricetin and myricitrin have been investigated in order to determine the relationship between flavonoid structure and protective activity towards oxidative stress i.e. lipid peroxidation induced by addition of hydrogen peroxide and/or Cu²⁺ ions. Among investigated flavonoids, quercetin showed the most enhanced and prolonged protective anti-oxidative activity. The nanomechanical (Young modulus) measurement of the MSNs treated DOPC membranes during lipid peroxidation confirmed attenuated membrane damage. By applying combination of experimental techniques (AFM, force spectroscopy, ELS, DLS), this work generated detailed knowledge about the effects of flavonoid loaded MSNs on the elasticity of model membranes, especially under oxidative stress conditions. Results from this study will pave the way towards the development of innovative and improved markers for oxidative stress-associated neurological disorders. In addition, the obtained could be extended to designing effective delivery systems of other high potential bioactive molecules with an aim to improve human health in general.

Two different silica conformations (Xerogels and Nanoparticles) both formed by the mediation of dendritic poly (ethylene imine) were tested at low pHs on the problematic uranyl cation sorption. The effect of crucial factors i.e., temperature, electrostatic forces, adsorbent composition, accessibility of the pollutant to the dendritic cavities and MW of the organic matrix was investigated to conclude the optimum formulation for water purification under these conditions. This was attained with the aid of UV-Visible and FTIR spectroscopy, dynamic light scattering (DLS), ζ-potential; Brunauer–Emmett–Teller (BET) porosimetry, Thermo Gravimetric Analysis (TG) and Scanning Electron Microscopy (SEM) Results highlighted that both adsorbents have extraordinary sorp-tion capacity. Xerogels are cost-effective since they approximate the performance of na-noparticles with much lesser organic content. Furthermore, they are more practicable materials since they may penetrate the pores of a metal or ceramic solid substrate in the form of a precursor, gel-forming solution.

This paper presents the concept of a novel adaptable sensing solution currently being developed under the EU Commission founded PHOTONGATE project. This concept will allow to quantify multiple analytes of the same or different nature (chemicals, metals, bacteria, etc.) in a single test with levels of sensitivity and selectivity at/or over those offered by current solutions. PHOTONGATE relies on two core technologies: a bio-chemical technology (molecular gates) which will confer the specificity and, therefore, the capability to be adaptable to the analyte of interest, and which combined with porous substrates will increase the sensitivity, and a photonic technology based on Local Surface Plasmonic Resonance (LSPR) structures serves as transducer for light interaction. Both technologies are in the micron range, facilitating the integration of multiple sensors within a small area (mm²). The concept will be developed for its application in health diagnosis and food safety sectors. It is thought as an easy-to-use modular concept, which will consist of the sensing module, mainly of a microfluidics cartridge that will house the photonic sensor, and a platform for fluidic handling, optical interrogation, and signal processing. The platform will include a new optical concept, fully Europe Union Made, avoiding optical fibers and expensive optical components.

A hydrophilic silica-based stationary phase with surface bound N-acetylglucosamine (GlcNAc-silica) was prepared in house and characterized physically via Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA) and chromatographically over a wide range of mobile phase compositions. While both FTIR and TGA confirmed the attachment of the GlcNAc ligands to the silica surface, the chromatographic evaluation of the GlcNAc-silica with polar and slightly polar standard solutes (e.g., sugars, nucleic acid fragments, phenolic and benzoic acid derivatives) yielded the typical hydrophilic interaction liquid chromatography (HILIC) behaviors in the sense that retention increased with increased solute’s polarity and the organic content (i.e., acetonitrile) of the hydro-organic mobile phase (i.e., ACN-rich mobile phase). Sugars derivatized with 1-naphthylamine (1-NA) and 2-aminoanthrcene (2-AA) such as xylose, glucose and short chains maltooligosaccharides constituted the most polar species for HILIC retention evaluation, and in addition the maltooligosaccharides offered a polar homologous series for gauging the hydrophilicity of the GlcNAc-silica in analogy with alkylbenzene homologous series and other nonpolar homologous for evaluating the hydrophobicity of non-polar stationary phases. On the other hand, the benzoic acid and phenolic acid derivatives were the probe solutes for evaluating the HILIC retention dependence of ionizable solutes on the pH of the mobile phase. Similarly, the nucleobase and nucleoside weak basic solutes as well as some typical cyclic nucleotide acidic solutes allowed the examination of the dependence of solute retention on the pH of the mobile as well as the polarity of the species.

Volumetric modification of transparent materials by femtosecond laser pulses is successfully used in a wide range of practical applications. The level of modification is determined by the locally absorbed energy density, which depends on numerous factors. In this work, it is shown experimentally and theoretically that, in a certain range of laser pulse energies, the peak of absorption of laser radiation for doughnut-shaped (DS) pulses is several times higher than for Gaussian ones. This makes the DS pulses very attractive for material modification and direct laser writing applications. Details of the interaction of laser pulses of Gaussian and doughnut shapes with fused silica obtained by numerical simulations are presented for different pulse energies and compared with the experimentally obtained data. The effect of absorbed energy delocalization with increasing laser pulse energy is demonstrated for both beam shapes while, at relatively low pulse energies, the DS beam geometry provides a stronger local absorption compared to Gaussian one. Implications of a DS pulse action on post-irradiation material evolution are discussed based on thermoelastoplastic modeling.

Some cancer cells rely heavily on non-essential biomolecules for survival, growth, and proliferation. Enzyme based therapeutics can eliminate these biomolecules, thus specifically targeting neoplastic cells; however, enzyme therapeutics are susceptible to immune clearance, exhibit short half-lives, and require frequent administration. Encapsulation of therapeutic cargo within biocompatible and biodegradable poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) is a strategy for controlled release. Unfortunately, PLGA NPs exhibit burst release of cargo shortly after delivery or upon introduction to aqueous environments where they decompose via hydrolysis. Here we show the generation of hybrid silica-coated PLGA (SiLGA) NPs as viable drug delivery vehicles exhibiting sub-200 nm diameters, a metastable Zeta potential, and high loading efficiency and content. Compared to uncoated PLGA NPs, SiLGA NPs offer greater retention of enzymatic activity and slow the burst release of cargo. Thus, SiLGA encapsulation of therapeutic enzymes, such as asparaginase, could reduce frequency of administration, increase half-life, and improve efficacy for patients with a range of diseases.

This study explores the shear-induced reversible gel behavior of suspensions containing silica na-noparticles and poly(ethylene oxide) (PEO). When subjected to vigorous shaking, these mixtures exhibit interesting shear thickening, transitioning from low-viscosity fluids to 'shake-gels' and then reverts to liquid after some time. Rheological measurements conducted at constant shear rates re-veal a significant increase in viscosity by several orders of magnitude occurring at specific time points during the process. Followed by the lowering of the shear rate implemented to understand the relaxation behavior. The investigation specifically examines the influence of various ions from the Hofmeister series on the gelation and relaxation dynamics of these suspensions. Results indicate that salts positioned on the right-hand side of the Hofmeister series, known as salting-in agents, facilitate quicker gelation and slower relaxation of the shake-gels. Conversely, salts on the left-hand side, referred to as salting-out agents, lead to slower gelation and faster relaxation. These observa-tions are attributed to the distinct effects that different salts exert on the conformation of PEO chains. Salting-in agents induce swelling of the polymer chains, enhancing their ability to interact and bridge between silica nanoparticles effectively, thus promoting rapid gelation and sustaining the gel structure for extended periods. In contrast, salting-out agents cause the polymer chains to collapse, reducing their bridging efficiency and resulting in delayed gelation along with a more rapid return to the fluid state during relaxation. Understanding the role of specific ions in modu-lating the gelation and relaxation behavior of colloidal-polymer suspensions provides valuable in-sights for tailoring material properties in various applications, including drug delivery, oil drilling, environmental restoration, coatings, and soft matter engineering.