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Abstract: The photo-induced reactivity of three nanostructured titanium dioxides including TiO2 nanoparticles (i.e., nano-TiO2), titania–silica aerogel and nanotextured TiO2 film, were investigated for gas phase photocatalytic oxidation of trichloroethylene and inactivation of Bacillus subtilis and Escherichia coli microbial cells. A correlation was observed between photoreactivity for TCE conversion and bactericidal activity within TiO2 of similar nanostructures and composition (i.e., elemental and phase). This indicates that the photogenerated radical species from UV-irradiated TiO2 responsible for TCE photo-oxidation also play a major role in the inactivation of microbial cells. The superb bactericidal activities of titania–silica aerogels (i.e., up to 6log reductions in viable B. subtilis) and nanotextured TiO2 film (3.4log reduction) compared to commercial Degussa P25 TiO2 (0.64log reduction) and optimum nano-TiO2 (1.3log reduction) far exceeds the observed activity enhancement for TCE photo-oxidation. This implies that nanoscale chemical and structural environment also contribute towards the bactericidal activities. [Copyright &y& Elsevier]

Abstract: Gas permeable, photoactive and crack-free titania–silica aerogels of high titanium content (i.e., up to Ti/Si=1) were prepared by two-steps acid–base catalyzed method involving an acid-catalyzed prehydrolysis of silicon alkoxide followed by a base-catalyzed hydrolysis/condensation reactions with a chelated titania precursor. The prepared titania–silica aerogels displayed good mechanical strength (>30kNm−2), large surface area (>550m2/g), mesoporous structure (8–11nm) and good gas permeation. The porous aerogels trap and filter airborne particulates and the titania–silica aerogel have a fair performance for aerosol (65%) and bioaerosol (94%) filtrations. The photoactive anatase nano-TiO2 crystallized within the aerogel displays an order of magnitude higher reaction rate for UVA photooxidation of trichloroethylene compared to commercial Degussa P25 TiO2. The bactericidal activity of the titania–silica aerogel for Bacillus subtilis cells under UVA was also six orders of magnitude better. [Copyright &y& Elsevier]

Abstract: A composite membrane was prepared by coating high surface area γ-Al2O3 on the porous ceramic support of the ZSM-5 membrane. A thin layer of γ-Al2O3 was coated on the surface of the individual ceramic particles to increase the contact surface by about 50m2. Ozone treatment of phthalate contaminated water showed that ozonization with traditional sparger in a batch reactor yielded a 1.1% decrease in TOC, and simply replacing the sparger with a membrane distributor gave a 20% TOC removal. Providing a membrane contactor increases this value to 25%, while simultaneous membrane pervaporation of water resulted in 40% TOC degradation. This shows that it is possible to achieved enhanced ozone water treatment from a compact membrane reactor unit that uses the combined function of membrane as distributor, contactor and separator. [Copyright &y& Elsevier]

This work describes a versatile electrospinning equipment with rapid, independent, and precise x–y–z movements for large-area depositions of electrospun fibers, direct writing or assembly of fibers into sub-millimeter and micron-sized patterns, and printing of 3D micro- and nanostructures. Its versatility is demonstrated thought the preparation of multilayered functional nanofibers for wound healing, nanofiber mesh for particle filtration, high-aspect ratio printed lines, and freestanding aligned nanofibers. [ABSTRACT FROM AUTHOR]

Organic solar cell (OSC) development continues to demonstrate impressive device efficiency improvements. However, the materials synthetic simplicity essential to industrialization remains seriously lacking attention, imparting inferior performance records in low‐cost devices. Hence, low bandgap and completely non‐fused electron acceptors (CNFEAs) having simple molecular structures are investigated herein. In contrast to typically explored fused‐ring acceptors with smaller backbone conformational variations, minimizing the interface recombination sites through a greater extent of localized domains is identified as more critical in CNFEAs, leading to remarkable fill factors (FFs) approaching 75%, among the highest currently realized for low‐cost systems. However, this comes with diminishing charge generation efficiency. The general ternary blend optimization strategy modifying the morphology of host components is limited in preserving such remarkably high FFs. To suppress the trade‐off while keeping notable FFs, a new perspective of constructing functionally bridged components based on optical, electronic, and thermodynamic properties is introduced here. Specifically, charge generation is unrestrained from the host acceptor localized domains through the introduction of a "bridge" component while also taking advantage of the configuration to channel polarons toward the efficient transport moieties of the host components. Accordingly, this work incubates understanding‐guided optimizations toward the advancement of more practical devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Two new reaction products were identified from DEET ozonation. • Transformation pathway and kinetics for both DEET and products were determined. • Rapid conversion of DEET did not decrease the bioactivity of the treated water. • Ozonation of DEET caused the increase of microtoxicity due to the carbamate product. Abstract N , N -diethyl- meta -toluamide (DEET) is the active ingredient in many insect repellants against biting insects such as mosquitoes and ticks. It is one of the few micro-pollutants that are increasingly found in natural waters. The fact that DEET occurs in both influent and effluent of wastewater treatment works is indicative of its refractory nature. This work investigates the reactions of DEET with ozone, an oxidant that is becoming more common in treatments and disinfections of wastewater and drinking water. The transformation pathways were mapped, and a reaction model that accurately predicts the reactions was developed. The ozonation of DEET did not decrease the bioactivity of treated water, but instead resulted in a twofold increase in the microtoxicity. The findings suggest that the products of DEET ozonation has greater toxicity potentials compared to the parent compound posing a real hazard to human health and environment. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 remains one of the biggest global health problems, which has already reached our wastewater through fecal shedding by COVID-19 patients. While the development of vaccines has mitigated the threats of the COVID-19 pandemic, the evolutionary dynamics of SARS-CoV-2 in wastewater lack monitoring and understanding. In this study, SARS-CoV-2 variants in wastewater were identified by analyzing 8511 wastewater-derived genome sequences from 9 countries from March 2020 to May 2023. The dominance of co-circulating variants was observed, namely B.1 in 2020, Alpha and Delta in 2021, then superseded by Omicron lineages in 2022 with a three-times increase. Mutations were also profiled, revealing nearly 5031 unique amino acid substitutions occurring approximately 371,591 times, some of which were associated with enhanced viral transmission and fitness. This study provided the first long-term multi-country overview of the prevalence of co-circulating SARS-CoV-2 lineages and mutations in wastewater and showed its comparison with conventional epidemiological surveillance. The results highlight the ability of wastewater-based genome monitoring to supplement clinical surveillance efforts in rapidly detecting viruses up to the strain level to keep track of their potential transmission routes and evolutionary dynamics. [ABSTRACT FROM AUTHOR]

Indoor exposure to volatile organic compounds (VOCs) is detrimental to the health of the occupants, and their removal is crucial in maintaining good air quality. Novel adsorbents prepared by modifying Metal-Organic Frameworks (MOFs), MIL101 (Cr), UiO-66, and UiO-66-NH 2 with [BMIM][CH 3 COO] ionic liquid, were characterized and tested for toluene adsorption. [BMIM][CH 3 COO]/MIL101 performed best with a fast sorption rate, large sorption capacity, and good regenerability. It displays synergistic interactions between the IL and MOF. Adding one weight percent [BMIM][CH 3 COO] to UiO-66 and UiO-66-NH 2 has a synergistic effect with respective 14% and 5% enhancements sorption over calculated values. The strong interactions between IL and UiO-66 and UiO-66-NH 2 , as observed in their thermogravimetric data, results in poor toluene sorption for 10 wt% [BMIM][CH 3 COO] loadings. This work provides a basis for IL modification of MOFs for enhanced sorption of VOCs for air treatment. [Display omitted] [ABSTRACT FROM AUTHOR]