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A novel ceramic nanofiber membrane (CNM), without an intermediate layer, was successfully developed onto the surface of a mullite fiber-based porous ceramic support using a sacrificial layer-assisted multiple dip-coating method. The CNM based on attapulgite exhibited a remarkable permeability of 1602.6 L/(m2·h·bar), over 24 times higher than the ceramic nanofiber membrane with a support made from alumina granular particles. Moreover, a catalytic ceramic nanofiber membrane (Mn@CNM) was fabricated via an impregnation method. The Mn@CNM coupled catalytic ozonation process achieved a removal efficiency of up to 90.3 % for degrading sulfamethoxazole (SMX). Furthermore, quenching experiments and electron paramagnetic resonance (EPR) analysis were conducted to evaluate the production of different reactive oxygen species (ROS) during the catalytic ozonation of SMX. The superior performance of Mn@CNM was ascribed to the high porosity and specific surface area of the CNM support, as well as the presence of a separation layer composed of interwoven APT nanofibers. These components created nano-sized pore structures, that enhanced the nano-confinement effect and improved the interaction between ROS and SMX molecules. In addition, the excellent redox cycles of Mn (III)/Mn (IV) facilitated the generation of ROS and degradation of SMX in catalytic ozonation systems. This study presents a novel method for creating CNM with excellent permeability and Mn@CNM with superior catalytic performance, enabling efficient removal of emerging contaminants from water. • Ceramic nanofiber membrane (CNM) was formed using a sacrificial layer-assisted multiple dip-coating method. • CNM exhibited a remarkable permeability of 1602.6 L/(m2·h·bar) without an intermediate layer. • Mn@CNM coupled catalytic ozonation process achieved a removal efficiency of 90.3 % for SMX. • APT nanofiber modified the CNM support, enhancing the specific surface area and nano-confinement effect. [ABSTRACT FROM AUTHOR]

Electric energy storage is currently the primary solution for addressing the intermittency and fluctuation of renewable energy sources. Traditional energy storage methods often struggle to simultaneously meet the demands of long storage duration, large capacity, high efficiency, and low cost. In this study, we present and verify the feasibility of a new energy storage method that utilizes hydraulic fracturing technology to store electrical energy in artificial fractures. Our study analyzed factors that impact energy storage capacity and efficiency, which provides a theoretical basis for optimizing hydraulic fracturing design for energy storage. This study also shows a promising direction for transforming depleted shale oil and gas wells into energy storage wells. • Introduced a novel energy storage approach that utilizes hydraulic fracturing technology to store electrical energy. • Provided a method for calculating energy storage capacity and efficiency. • Verified the feasibility of hydraulic fracturing energy storage. • Demonstrated that hydraulic fracturing energy storage can meet long-duration requirements. • Demonstrated great potential of transforming depleted shale oil and gas wells into energy storage wells. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide/titanium dioxide nanotube (rGO/TNT) composites have superior properties, such as a large surface area, extraordinary mechanical strength, high carrier mobility, etc. However, the biosafety and biocompatibility of these composites, such as their influences on cell viability and cell functions, which are of paramount importance, are still not fully addressed. In this study, rGO/TNT nanocomposites were successfully synthesized through a modified hydrothermal treatment method. Then, the interactions between the rGO/TNT nanocomposites and Raw264.7 mouse monocyte-macrophage cells were further investigated. The results show that the rGO/TNT nanocomposites could be internalized by Raw264.7 cells and mainly gathered inside the cytoplasm. No rGO/TNT nanocomposites were observed in the nucleus. Moreover, the rGO/TNT nanocomposites exhibited low cytotoxicity toward Raw264.7 cells at a lower dose, though they may exhibit cytotoxicity to some extent at very high concentrations. In addition, the uptake of the nanocomposites influenced the cell cytoskeleton organization, while the cell adhesion and migration abilities were also impaired. [ABSTRACT FROM AUTHOR]

The cleaning of traditional ceramics consumes much water and detergents. It is valuable to consider how to endow the ceramics with self-cleaning character. In this paper, titanic-based-crystallites (CaTi(SiO 5) or TiO 2) superhydrophilic glazes with superior self-cleaning properties were in situ prepared by a simple one-time firing method. There is no any extra treatment involved in the preparation process. It was found that the precipitation of titanic-based crystallites in the glaze could be adjusted by controlling the cooling system. The transformation mechanism of the phase was analyzed based on the phase separation state. Stress conditions of a dirt cell on surfaces with different roughness were discussed. The correlation between geometric structure and self-cleaning performance demonstrated that the multi-level structure is vital for self-cleaning performance. The self-cleaning mechanism of the superhydrophilic glaze was proposed. The titanic-based crystallite glazes possess superhydrophilic characteristics (<8.0 °), high hardness (642.44–707.85 kgf·mm−2), and excellent self-cleaning performance to oily ink stamps and relatively good performance to human fecal simulacrum, the miso sauce, due to the multi-level structure with nano-scale surface roughness, showing a good application potential on the self-cleaning domain, i.e. glass and traditional ceramic, etc. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic significantly impacts people's sentiment and mental health, threatening their health and lives. We gathered 4.17 million geotagged social media posts from Weibo and scrutinized the nuances of the collective sentiments of netizens in four megacities in China during the first pandemic wave (from 1 December 2019 to 30 April 2020). Our findings suggest that the COVID-19 outbreak significantly reduced the Sentiment Index (SI) in China's cities, and the collective sentiments expressed in Wuhan were even more negative than those in the other three megacities. We explored the uncharted impacts of exposure to three geographical environment factors (GEFs) on SIs. Public exposure to greenspaces increased, while exposure to indoor built spaces decreased during the lockdown period. The exposure to sidewalks increased in rural areas but decreased in the main urban areas. The contributions of various GEFs to the SIs were the lowest during the lockdown period, and SIs were strongly affected by the pandemic. However, greenspace had the most potent effect on SIs, improving public sentiment resilience and mitigating mental health risks. [Display omitted] • Positive public sentiment declined during the COVID-19 pandemic. • People tend to increase their contact with greenspace during the pandemic. • Greenspace is the most important geographical influence factor of public sentiment. [ABSTRACT FROM AUTHOR]

Meso-tetra (4-carboxyphenyl) porphyrin (H 2 TCPP) loaded on the surface of TiO 2 nanotubes (TNTs) by modification of reduced graphene oxide (rGO) nanostructures has been successfully performed through improved hydrothermal and heating reflux composite technology. The influence of rGO and H 2 TCPP on the co-photocatalytic behavior of TNT during the degradation of Methylene blue (MB) were studied. The novel photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and electron paramagnetic resonance (EPR). The results from these investigations provide a deeper insight into the materials chemistry of H 2 TCPP/rGO-TNT nanocomposites. Additionally, the photocatalytic activity was evaluated by the photodegradation of MB under irradiation with visible light. The degradation results showed a purification of more than 92% MB in wastewater, which is about 4.3 times higher than that of the pure TNT. The results confirm that the prepared H 2 TCPP/rGO-TNT nanocomposites possess superior absorption and co-photocatalytic activities. First, graphene works as the adsorbent, electron acceptor and transporter to efficiently increase the separation of the electron–hole pairs. Then it can accelerate the decomposition of organic pollutants. Second, the H 2 TCPP plays a critical role in capturing photons and expands the absorption wavelength to the visible light region when dealing with water resource. [ABSTRACT FROM AUTHOR]

In this paper, TiO 2 nanotubes (TNT) co-sensitized with copper(II) meso -tetra(4-carboxyphenyl)porphyrin (CuTCPP) and reduced graphene oxide nanosheets (rGO), which was fabricated through two-step improved hydrothermal method and heating reflux process. The effect of rGO and CuTCPP on the co-photocatalytic behavior of TNT for the degradation of Methylene Blue (MB) were measured under visible light irradiation. The photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), selected area electronic diffraction (SAED), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and electron paramagnetic resonance (EPR). The results provide a deeper insight into the co-photocatalytic mechanism of CuTCPP/rGO-TNT nanocomposites. The degradation results showed a purification of more than 95% MB in wastewater, which is about 5 times higher than that of the pure TNT. The results also confirm the prepared CuTCPP/rGO-TNT nanocomposites possess superior co-photocatalytic activities. [ABSTRACT FROM AUTHOR]

Abstract: A new consolidation system for fragile ancient silk fabrics by fibroin with the support of ethylene glycol diglycidyl ether (EGDE) was developed in our group. To figure out the mechanism and the effect of EGDE in the system, aged silk fabrics treated with EGDE have been investigated in this paper. Silk fabrics were artificially aged in sodium hydroxide aqueous solution to simulate fragile ancient silk fabrics. The aged silk fabrics were treated with EGDE aqueous solution by spraying. The resultant silk fabrics were systematically investigated by tensile test, thermogravimetric analysis (TGA), thermal ageing resistance test, attenuated total reflection Fourier transform infrared spectroscopy (ATR–FTIR), solid-state 13C cross polarization/magic angle spinning nuclear magnet resonance (13C CP/MAS NMR) and amino acid analysis (AAA), etc. Results indicate that the breaking stress and strain of the treated silk fabrics increase more than four and two times, respectively. The maximum decomposition temperature of the treated silk fabrics is much higher than that of the aged silk fabrics. The treated silk fabrics exhibit a better thermal ageing resistance than the aged silk fabrics. Chemical interactions occurred between EGDE and silk fibroin molecules in silk fabrics. This work provides useful information for the protection of historic silk fabrics. [Copyright &y& Elsevier]

• The crack and damage characteristics of rock salt were investigated in multi-stage cyclic loading. • Under multi-stage cyclic loading, the mid-frequency signals had the highest amplitude, followed by low- and high-frequency signals. • Compared to the increased lower limit stress, the constant lower limit stress promoted the development of shear cracks. Rock salt is a common sedimentary rock found in the crust and is widely used for underground energy storage and waste disposal. This research conducted multi-stage cyclic loading on impure Huai'an rock salt while monitoring acoustic emissions (AE) in real-time. The results show that as the loading stress increases, the cumulative AE energy increases in a stepwise manner. The frequency distribution displays a band pattern of low, medium, and high frequencies. As the loading stress increases, the proportion of high-frequency signals decreases while that of low-frequency signals increases. The proportion of medium-frequency signals remains consistently the highest. The b -value initially decreases and then increases, with a sharp drop near the failure. Compared to the increased lower limit stress (ILLS), the constant lower limit stress (CLLS) causes higher cumulative AE energy and amplitude, and smaller b -values for the salt samples. These results indicate that the CLLS increases the size of cracks and damage in the salt samples. Based on the RA (risetime/ amplitude)- AF (average frequency) distribution, it is found that the primary mode of failure for rock salt under multi-stage cyclic loading is tensile cracking. Compared to the ILLS, the CLLS promotes the development of shear cracks. The AE test results of the rock salt provide an important basis for explaining the in-situ microseismic signals generated during the operation of salt cavern energy storage. [ABSTRACT FROM AUTHOR]

Hydrogen production from electrocatalytic water splitting has aroused extensive attention in many fields recently. Fabrication of low-cost and high-efficiency electrocatalysts are still an urgent and challenging work. Porphyrins as visible-light photosensitizers have been extensively utilized in visible-light photocatalysts and photoelectronic materials. So, fabrication of novel porphyrin-based complexes will be benefited for high-efficiency hydrogen evolution and photoelectric response. Here a series of zirconium porphyrin-based coordination complexes were successfully fabricated via a facile two-step strategy. Due to the unique long chain-like structure and low charge-transfer resistance, the zirconium porphyrin-based coordination complexes displayed excellent electrocatalytic performance for hydrogen evolution reaction. The ZrTPP-PTA-1 showed a low overpotential of 60 mV at the current density 10 mA cm−2 and a Tafel slope of 87 mV dec−1 with an ultralow electron transfer resistance of 17.5 Ω. In addition, a quick photocurrent response occurred for these coordination complexes with a visible-light illumination. The photocurrent of the ZrTPP-OA-2 rised up to 2.5 μA under visible-light irradiation. With this pleasant result, these zirconium porphyrin-based coordination complexes have a great potential to become available alternative of current noble electrocatalysts for photoelectric application. • 1D long chain-like porphyrin-based coordination complexes were fabricated. • 1D nanostructure is in favor of photogenerated charges separation and transfer. • The complexes have high-efficiency hydrogen evolution. • The complexes have better photoelectric response. • The complexes have great potential for electrocatalyst and photoelectric material. [ABSTRACT FROM AUTHOR]

Exploiting an inexpensive and high-effective composite catalyst for electrocatalytic hydrogen evolution and elimination of organic contaminant from wastewater has drawn great attentions recently. Herein, a facile two-step hydrothermal process was successfully adopted to realize the growth of MoS 2 nanosheet on the surface of unique TNT@CNTs (TC). Remarkable, the optimized MoS 2 /TNT@CNTs (MTC) catalyst exhibited high-efficient photocatalytic activity for high concentrations (30 mg/L) of methylene blue (MB) and rhodamine B (RhB) with the photodegradation rate of 98.7% and 99.0% in 50 min, which are 2 and 6 times higher than that of pure TiO 2 nanotube (TNT), respectively. Meanwhile, the novel composites also showed better hydrogen evolution reaction (HER) activity with the overpotential of 110 mV. The significant enhance in photocatalytic performance and electrocatalytic activity are attribute to formation of chemical bonds and large specific surface area, which effectively separate and transfer interfacial charges. The radical scavenging techniques confirmed that the holes (h + ) and •O 2 − radicals played a main role in the photocatalytic process. This study suggests that the novel nanocomposite has extensive application to solve environment and energy issues due to the low-cost raw materials, simple and inexpensive synthesizing process and environmental-friendly methods. [ABSTRACT FROM AUTHOR]

Silica-alumina gel with micrometer-sized macropores and nanometer-sized mesopores has excellent advantages in humidity control properties. The macropores provide pathways for rapid H 2 O molecular transportation while the mesopores present a large surface area. An amorphous spherical silica-alumina beads material with a distinct bimodal pore structure was prepared by sol–gel reactions of tetraethoxysilane (TEOS) and aluminum nitrate in the presence of poly(ethyleneoxide) (PEO). It features high moisture adsorption capacity, super fast response to humidity changes, small equilibrium humidity control range and macroscopic spherical morphology. The appearance and structural properties of the material were investigated by digital camera, scanning electronic microscope (SEM) and thermal gravimetry and differential thermal analyses (TGA/DTA). The porosity features are further established by N 2 sorption experiments and pore size distribution analysis. The bonding characteristics and coordination features around aluminum have been studied using Fourier transform infrared spectroscopy (FTIR) and 27 Al magic angle spinning nuclear magnetic resonance ( 27 Al MAS NMR). The humidity control performance of the material at relative humidity was measured. The results revealed that the material kept a relative humidity in the range of 39.3–40.3%, 47.6–50.7% and 57.2–60.7%, respectively, under three different pre-treating conditions. And the humidity controlling equilibrium levels were all reached within 3 h. Therefore, the material could maintain a suitable relative humidity of 40–60% in enclosed spaces such as showcases in museums and galleries. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report a new process to prepare humidity control materials. [•] The process is easy to perform and does not produce any harmful resultant. [•] This material can serve as intelligent humidity control material. [•] Good properties depend on the surface area and the distribution of pores. [•] Possible reasons for humidity control properties are discussed. [Copyright &y& Elsevier]

With increasing industrialization of food production, residues of organophosphorus pesticides (OPs) are more frequently found in the environment including rivers, lakes and soils. Extended exposure to OPs, even at a level below 1 nM, may lead to liver and central nervous system damages in humans and animals, while existing detection methods are not sensitive enough to detect OPs at trace levels. We presented a simple-to-use aptasensor to rapidly detect broad-spectrum OPs with high sensitivity. DNA aptamer was modified on the surface of a micro interdigitated electrode chip, and AC electrokinetics was employed to accelerate the binding of OP molecules to the aptamer probe. The sensing strategy directly measured the interfacial capacitance whose change rate was adopted as a quantitative indicator of recognition events, with a sample to result detection time of 30 s. This aptasensor had a wide linear range of (fM ~ nM), and the detection limit reached (0.24–1.67) fM for four highly-toxic OPs, with good specificity. It still showed good activity after being stored in non-refrigerated environment for at least 14 days. This aptasensor as well as the detection method offer a promising solution for on-site and real-time sensitive OP detection. • A highly sensitive aptasensor is presented for on-site real-time detection of organophosphorus pesticides (OPs). • Simultaneous detection of profenofos, isocarbophos, omethoate and phorate is achieved, with similar responses. • The sensor reaches a limit of detection at fM level, a wide linear range from fM to nM, and a good selectivity. • This sensor is easy to prepare, store and operate. It is effective in detecting practical OPs in emulsifiable concentrate. [ABSTRACT FROM AUTHOR]

The ultrasensitive detection of fibroin in unearthed silk relics has great significance for investigating the origin and transmission of silk. In this study, an anti-fibroin monoclonal antibody was successfully prepared through animal immunization. Next, a label-free electrochemical immunosensor was fabricated using layer-by-layer self-assembly technology, and an indirect enzyme-linked immunosorbent assay (ELISA) was proposed. The two methods exhibited excellent sensitivity and specificity in the detection of silk fibroin, while the immunosensor showed a wider quantitative detection range (0.1–100 ng mL−1) and a lower detection limit (0.051 ng mL−1) than ELISA (10–100 ng mL−1 and 8.71 ng mL−1). Furthermore, the performance of the immunosensor was superior in archaeological sample detection. Taking advantage of the well-prepared monoclonal antibody, the two proposed immunological assays demonstrate tremendous potential for the ultrasensitive detection of silk fibroin, which can make great contributions to exploring the origin and transmission routes of ancient silks. • Ultrasensitive detection for ancient silk has great significance to investigate the origin and transmission of silk. • A specific anti-fibroin monoclonal antibody was well designed and prepared. • A novel label-free electrochemical immunosensor and an indirect ELISA were proposed. • The immunosensor exhibited a low detection limit of 0.051 ng mL−1 for silk fibroin detection. • The performance of the immunosensor was excellent in qualitative and quantitative tests of ancient silks. [ABSTRACT FROM AUTHOR]