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To separate oil–water mixtures especially in oil field operations, new energy-efficient methods are urgently required. Conventional separation techniques using demulsifiers for separation of oil–water mixtures or even use of membranes usually suffered from high cost and energy consumption, composition dependency of demulsifiers and fouling or inability of a single membrane to separate all types of oil–water mixtures. This research aimed to synthesize tungsten oxide-coated stainless steel mesh using the hydrothermal method, with a focus on evaluating its effectiveness in oil–water separation. The coating procedure was carried out using hydrothermal techniques, with an emphasis on investigating the impact of precursor concentration, pH levels, reaction temperature and duration, on the separation efficiency of the optimal coating solution. The hydrothermally coated stainless steel mesh was created within a polytetrafluoroethylene reaction vessel, submerged in a 150 ml aqueous solution containing 0.0094 mol of sodium tungstate di-hydrate at pH 3.0, achieved through the addition of hydrochloric acid. Additionally, 1 g of oxalic acid, acting as a chelating agent, was introduced. Subsequently, the mesh underwent a 4 h reaction at 220 °C and was subsequently annealed for 30 min in a 350 °C furnace. Remarkably, the resultant mesh exhibited an exceptional water separation flux of 9870 ± 15 L/hr/m2 when exposed to 1:1 v/v oil–water mixtures. This performance significantly outperformed previous filters designed for similar oil–water separation tasks. The mesh efficiently facilitated the passage of water through the oil–water mixture, achieving an efficiency rate exceeding 98 ± 1%. To gauge its wetting behavior, the hydrophilic/underwater oleophobic filter underwent static contact angle measurements. The filter's wetting mechanism was primarily attributed to its hierarchical surface structure, which enhanced surface hydrophilicity and roughness. Analytical techniques such as XRD, FTIR, and FE-SEM were employed to scrutinize the fabricated filter's composition. These analyses confirmed the successful creation of a nanostructured WO3 coating on both sides of the stainless steel mesh. Moreover, the utilization of commercially available chemicals and straightforward fabrication techniques underscores the promising potential of this approach for large-scale applications. [ABSTRACT FROM AUTHOR]

The color of the tablets and capsules produced by pharmaceutical companies is important from the perspectives of product branding and counterfeiting. According to some studies, light can change tablet color during storage. In this study, tablets comprising amlodipine besylate (AB), a well-known light-sensitive drug, were coated with commonly used coating materials and exposed to light. Compared to the tablets that were not exposed to light, the color of those exposed to light changed over time. In fact, a faster and more pronounced color change was observed in the tablets exposed to light; however, the amount of AB did not decrease significantly in these tablets. The coating materials and their amounts were varied to clarify the materials involved in the color change. Based on the results, titanium dioxide and hypromellose may be involved in the color change process. As titanium dioxide is a photocatalyst, it may induce or promote chemical changes in hypromellose upon light irradiation. Overall, care should be exercised during selection of the coating polymer because titanium dioxide may promote photodegradation of the coatings while protecting the tablet's active ingredient from light. [ABSTRACT FROM AUTHOR]

This paper reports on the photodegradation of ibuprofen (IBP), as a model pharmaceutical, using SiO2@xTiO2 synthesized via a hydrothermal method. The catalysts were prepared by adding TiO2 at different weight loadings (2, 5, 10 and 20 wt%) to a Stober synthesized silica (ca. 120 ± 10 nm diameter). The core–shell materials were characterized by TEM, XRD, reflectance diffuse spectroscopy, Raman spectroscopy, BET analysis and electrical conductivity. The photodegradation was performed using UV irradiation (254 nm, 25 W). The effect of catalyst dosage and the pH of the solution on the rate of IBP photodegradation was investigated. The SiO2@xTiO2 showed excellent photodegradation efficiency and the decomposition reaction was found to be pseudo first order where the degradation rate of IBP increased with the formation of H2O2. Optimal experimental conditions gave 99% IBP degradation with the SiO2@20TiO2 catalyst (0.1 g/L, at 180 min of irradiation). [ABSTRACT FROM AUTHOR]

Ultraviolet irradiation confers titanium dioxide amphiphilicity. Unlike the UV-induced hydrophilic properties that had a long history of academic interest, oleophilicity has not received much attention. This study aims to investigate the molecular evidence of lipid adsorption onto UV-treated TiO2 surface by in vitro and in silico approaches. Artificial lipid vesicles were fabricated for empirical confirmation of the increased oleophilicity of the TiO2 surface after UV irradiation and in silico model was developed for computational simulation of the underlying molecular dynamics. After UV treatment and application of a synthetic liposome solution, the TiO2 surfaces were analyzed for surface roughness and the trace of lipid molecules by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and fluorescence confocal microscopy. The surface roughness was reduced and the increased liposome residues on the surface of TiO2 were observed after UV irradiation. The in silico simulation of molecular dynamics predicted higher non-covalent bonding energy to phospholipids and a closer atomic distance between the lipid molecules and the TiO2 surface after UV irradiation. These data suggested that UV irradiation enhanced the oleophilicity of the TiO2, presumably by the result of the hydrogen bonds between lipid and TiO2. Further studies on the oleophilicity of TiO2 are required to elucidate the osseointegration process of UV-treated implant fixtures in hyperlipidemic patients. [ABSTRACT FROM AUTHOR]

The low cost, accessibility, and ease of implementation of SiO2 hydrophilic coatings should encourage further promotion as practical surface treatments. The calcination process, however, poses an obstacle to convenience. Herein, a calcination-free, antifogging SiO2 superhydrophilic coating was prepared at room temperature by sol–gel method with the guidance of particle gradation theory, which was used to regulate the size and concentration of colloid nanoparticles. The surface micromorphology, roughness, and water contact angle (WCA) of coatings were characterized and measured using scanning electron microscope (SEM), atomic force microscope (AFM), and contact angle measuring equipment. The antifogging capability of superhydrophilic coating was also examined. It has been found that hydrophilicity of coatings can be significantly improved by reasonable particle gradation design. The closer the particle packing pattern is to the hexagonal close-packing model, the better the hydrophilicity of coatings. When the concentration ratio of particle diameter 60.29, 9.26, and 3.68 nm is 15:4:1, the coating exhibits exceptional hydrophilicity (WCA, 2.3°) and outstanding anti-fogging performance. An implication of this study is that a versatile and easily manipulated strategy is presented here for designing surface microstructures that are sensitive to roughness. Highlights: The calcination-free SiO2 superhydrophilic coating was successfully prepared by the sol-gel method. Reasonable matching of colloidal silica particle size can effectively improve the coating hydrophilic performance. The silica coating exhibits exceptional hydrophilicity (WCA, 2.3°) and outstanding anti-fogging performance. [ABSTRACT FROM AUTHOR]

In situ characterization of materials in their operational state is a highly active field of research. Investigating the structure and response of materials under stimuli that simulate real working environments for technological applications can provide new insight and unique input to the synthesis and design of novel materials. Over recent decades, experimental setups that allow different stimuli to be applied to a sample inside an electron microscope have been devised, built, and commercialized. In this review, we focus on the in situ investigation of optically active materials using transmission electron microscopy. We illustrate two different approaches for exposing samples to light inside the microscope column, explaining the importance of different aspects of their mechanical construction and choice of light source and materials. We focus on the technical challenges of the setups and provide details of the construction, providing the reader with input on deciding which setup will be more useful for a specific experiment. The use of these setups is illustrated using examples from the literature of relevance to photocatalysis and nanoparticle synthesis. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive review of recent studies on the superacid-catalyzed preparation of ionic polyhedral oligomeric silsesquioxanes (POSSs) and their properties, polymerization, and hybridization, that have been developed by the author and co-workers so far. Octameric POSSs (T8-POSS) containing ammonium side-chain groups as the main products can be obtained at a high yield within a short reaction time by dissolving amino group-containing organotrialkoxysilanes in an aqueous superacid (e.g., trifluoromethanesulfonic acid) solution, followed by hydrolytic condensation by heating in an open system to evaporate the solvents. When these reactions were performed in a hydrophobic alcohol, such as 1-hexanol, a POSS mixture with a high proportion of decameric POSS (T10-POSS) was obtained. It was found that the proportion of T10-POSS can be increased by properly controlling the reaction conditions (temperature, pressure, and solvent evaporation time) using a Kugelrohr apparatus during POSS preparation in an aqueous superacid solution. Furthermore, a low-crystalline POSS and ionic liquids containing POSS components can be obtained by the superacid-catalyzed hydrolytic condensation of the mixtures of two types of organotrialkoxysilanes containing functional groups, which can be converted into ionic groups. This superacid-catalyzed hydrolytic condensation can be applied to the preparation of carboxyl-functionalized POSSs and an ammonium-functionalized specific cyclotetrasiloxane isomer. An antifogging film with a hard-coating property comprising polyamide obtained by the polycondensation of ammonium- and carboxyl-functionalized POSSs was developed as an ionic POSS application. Furthermore, using an ionic POSS and cyclotetrasiloxane as crosslinking agents, polyacrylamide hydrogels exhibiting extremely flexible and irrefrangible properties can be obtained. Highlights: Ionic POSSs can be obtained at a high yield within a short reaction time using superacid catalysts. The POSS size can be controlled by properly selecting the solvent type and reaction conditions. Low-crystalline ionic POSS can be obtained from a mixture of two types of organotrialkoxysilanes. Ionic liquids containing POSS components can be obtained from the mixture of two types of organotrialkoxysilanes. An antifogging film and hydrogel with flexible and irrefrangible properties were developed using ionic POSSs. [ABSTRACT FROM AUTHOR]

A novel plasma treatment source for generating cylindrical plasma on the surface of titanium dental implants is developed herein. Using the titanium implant as an electrode and the packaging wall as a dielectric barrier, a dielectric barrier discharge (DBD) plasma was generated, allowing the implant to remain sterile. Numerical and experimental investigations were conducted to determine the optimal discharge conditions for eliminating hydrocarbon impurities, which are known to degrade the bioactivity of the implant. XPS measurement confirmed that plasma treatment reduced the amount of carbon impurities on the implant surface by approximately 60%. Additionally, in vitro experiments demonstrated that the surface treatment significantly improved cell adhesion, proliferation, and differentiation. Collectively, we proposed a plasma treatment source for dental implants that successfully removes carbon impurities and facilitate the osseointegration of SLA implants. [ABSTRACT FROM AUTHOR]

External thermal insulation composite systems (ETICS) have been extensively applied on building façades with the aim of implementing the thermal and aesthetical properties of the building envelope. However, the formation of stains and deposition of particulate matter is often observed in the surface of these systems. The use of multifunctional products with self-cleaning properties can reduce surface anomalies and thus enhance the durability of ETICS. This study aims at evaluating the effectiveness of three protective coatings with self-cleaning additives (i.e., TiO2 nanoparticles), when applied on the surface of ETICS. Three different stains (rhodamine, methylene blue and silver paint aerosol) were applied on the ETICS finishing coat, evaluating the removal of these stains after exposure to natural (solar radiation) light source. The surface properties (compactness, hardness, roughness, gloss, and color) of the ETICS were evaluated prior and after sun exposure. Results showed that the application of the three products lead to a modification of the surface properties (compactness, hardness, gloss, roughness) of the ETICS specimens, and sensibly enhance the self-cleaning, hydrophobic and aesthetical properties of the ETICS. [ABSTRACT FROM AUTHOR]

Hydrophilic photocatalytically active ZnO and ZnO thin films doped with Yb2O3 and Eu2O3 (rare earth metal oxide, REM) with optical transmittance exceeding 76% in the visible light range (λ = 550 nm) were prepared by a combination of sol–gel technique, spin-coating and high temperature thermal treatment at 500 and 600 °C. The thin films were tested using advanced research methods, i.e.: morphology and topography and fractures along with approximate thickness values were investigated on scanning electron microscope (SEM), chemical composition was determined using X-ray Energy Dispersive Spectroscopy (X-ray Energy Spectroscopy), topography and roughness were measured on atomic force microscope (AFM), water contact angle values were determined by sitting water droplet method, optical properties of the fabricated materials were investigated using UV/Vis spectrophotometer. The decolorization efficiency of rhodamine B in aqueous solution was analyzed over a period of 190 min, obtaining degradation rates of: 54.7% and 43.1%, for ZnO and ZnO coatings doped with ytterbium oxide and europium oxide, respectively. The roughness of thin hybrid coatings did not exceed 50 nm, ensuring effective absorption of electromagnetic radiation by the layers. The methodology presented by the authors for the fabrication of thin hybrid films characterized by the key properties of self-cleaning coatings can be successfully applied to coatings of photovoltaic panels and architectural glass structures. [ABSTRACT FROM AUTHOR]

The wettability-switching properties of superhydrophobic/hydrophilic surfaces have generated significant interest to researchers worldwide. Controlling the wettability on the surface holds considerable promise for potential applications like self-cleaning surfaces, anti-freezing, and anti-corrosion. Switching wettability is still a challenging issue in research field. In this work, we have synthesized gold (Au)-decorated TiO2 nanowire (NW) and analyzed the switching wettability behavior under specific UV light conditions. The wettability test result displays the water contact angle (WCA) of Au-decorated TiO2-NW and TiO2-NW as 122° and 70°, respectively. After the UV irradiation, WCA of the Au-decorated TiO2-NW and TiO2-NW changed to 47° and 43°, the wettability transition rate obtained was 2.3 × 10–4 degree−1 min−1 and 1.5 × 10–4 degree−1 min−1, respectively. The value of friction force and work of adhesion of Au-decorated TiO2-NW is 14.10 µN and 34.22 mN/m. Improved switching wettability behavior has been observed for Au-decorated TiO2-NW compared to TiO2-NW sample. This improvement is due to effective carrier separation and enhanced lifetime of charge carriers. Hence the enhanced wettability parameters in Au-decorated TiO2-NW structure can provide a great potential application in self-cleaning and antifogging smart surfaces. [ABSTRACT FROM AUTHOR]

Nanoparticles can undergo aging phenomena in sewage treatment systems, which alter their physical and chemical properties. However, the effect of aged nanoparticles on the dewatering performance of activated sludge under long-term low concentrations is yet to be reported in sewage treatment systems. Here, we compared the chronic effects of pristine and aged TiO2 nanoparticles on the sludge dewatering index, which includes specific resistance to filtration (SRF) and bound water (BW) in a sequencing batch reactor (SBR) at μg/L concentration levels, and analyzed the relevant mechanisms. The results indicated that aging in the sludge supernatant altered the photosensitivity and water stability of nanoparticles, which was mainly due to the changes in the zeta potential and energy band of the particle and was ultimately attributed to the combined effect of particle surface inclusions such as organic matter and inorganic salt. At 10 μg/L, nanoparticles reduced the sludge dewaterability, which observed an improvement at 100 μg/L. This is because 10 μg/L promoted the secretion of extracellular polymeric substances (EPS), which regulated the structure of sludge flora and increased the abundance of secreted quorum sensing-acyl-homoserine lactones (QS-AHL) and EPS genera, while the corresponding exposure results for 100 μg/L were the opposite, owing to the damage and necrosis effects caused by exposure under long-term light, which reduced EPS production and increased sludge density. Interestingly, aging could alleviate the effects of two exposure concentrations on sludge dewatering, mainly because of the decrease in the photoactivity of the nanoparticles. The results of this study show that environmental aging could delay, but not reverse the results of exposure to specific concentrations of nanoparticles. However, the significantly different ecological effects of photosensitive nanoparticles with two environmentally relevant concentration should be refined and confirmed again in freshwater environments to provide a basis for subsequent scientific management and control of photosensitive nanoparticles. [ABSTRACT FROM AUTHOR]

Increase of the enteric bacteriophages (phage), components of the enteric virome, has been associated with the development of inflammatory bowel diseases. However, little is known about how a given phage contributes to the regulation of intestinal inflammation. In this study, we isolated a new phage associated with Enterococcus gallinarum, named phiEG37k, the level of which was increased in C57BL/6 mice with colitis development. We found that, irrespective of the state of inflammation, over 95% of the E. gallinarum population in the mice contained phiEG37k prophage within their genome and the phiEG37k titers were proportional to that of E. gallinarum in the gut. To explore whether phiEG37k impacts intestinal homeostasis and/or inflammation, we generated mice colonized either with E. gallinarum with or without the prophage phiEG37k. We found that the mice colonized with the bacteria with phiEG37k produced more Mucin 2 (MUC2) that serves to protect the intestinal epithelium, as compared to those colonized with the phage-free bacteria. Consistently, the former mice were less sensitive to experimental colitis than the latter mice. These results suggest that the newly isolated phage has the potential to protect the host by strengthening mucosal integrity. Our study may have clinical implication in further understanding of how bacteriophages contribute to the gut homeostasis and pathogenesis. [ABSTRACT FROM AUTHOR]