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Photocurrent density of the spherical CdSe/Cd 0.25 Zn 0.75 Se QDs based photoanode, showing a saturated photocurrent density of 13.5 mA/cm2 and a stable H 2 generation under one sun illumination. [Display omitted] • We report a highly stable photoelectrochemical H 2 evolution based on core/shell QDs. • The hole transfer rate is strongly improved by engineering the band structure of QDs. • The device can maintained 99% of its initial current density after 10 h illumination. Colloidal quantum dots (QDs) are promising photosensitizers for the conversion of solar energy into electric energy or chemical fuels. Particularly, they are potentially used in photoelectrochemical (PEC) devices for the realization of solar-driven hydrogen (H 2) generation because their optoelectronic properties could be tunable by controlling their size/shape/composition. However, the long-term operation stability of the PEC devices based on QDs is not good, which is strongly prohibited the potential of the QDs based PEC hydrogen production. Here, we engineer the band structure of the CdSe QDs via a Zn dopant and demonstrate a highly stable PEC devices based on CdSe/Cd 1-x Zn x Se QDs. Through controlling the molar ratio of Cd/Zn precursors, the Zn concentration in the shell can be finely controlled to form an alloyed shell of Cd 1-x Zn x Se. The alloyed shell enables the efficient hole transfer from the QDs to TiO 2 , benefiting from the optimization of the valence energy alignment between the core and shell. As a proof-of-concept, the PEC device based on alloyed-shell QDs achieves a current density of ∼ 13.5 mA/cm2, which is comparable to the best reported PEC devices. More importantly, the PEC devices maintained 99% of its initial current density after 10 h of continuous H 2 generation under one sun illumination. Even after 50 h operation, the PEC device still keeps 65% of initial current density. The excellent long-term operation stability paves the way for the design and use of doped QDs for potential H 2 production. [ABSTRACT FROM AUTHOR]

Conducting electrospun nanofibrous mats elicit great interest in a wide range of applications. In this paper, polyurethane/polyaniline (PU/PANi) mats were prepared via the elecrospinning route with a polyurethane/dimethyl formamide spinning solution, and then in situ chemical polymerization of aniline monomers on the surface of PU nanofibers to deposit conductive PANi layer. In details, the morphology and structure of the PU/PANi mats were characterized by SEM, FTIR and the results indicated that the polyaniline stably deposited on the surface of polyurethane nanofiber. The electrical conductivity measurements indicated PU/PANi mats expressed good electrical conductivity (0.43 S/cm) at the optimal polymerization time as 120 min. As expected, PU/PANi mats showed strain sensitivity of ( R-R 0 )/ R 0 = 0.75 (curvature = 0.4 cm −1 ) and the average strain gauge factor could reach 17.15 with applied stretching deformation (0 ∼ 110%). Therefore it could be deemed as the recommended nano-materials for flexible wearable device. [ABSTRACT FROM AUTHOR]

This study used Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and Fourier transform near-infrared (FT-NIR) spectroscopy with principal component regression (PCR) and partial least squares regression (PLS) to build hardwood prediction models. Wet chemistry analysis coupled with high performance liquid chromatography (HPLC) was employed to obtain the chemical composition of these samples. Spectra loadings were studied to identify key wavenumber in the prediction of chemical composition. NIR–PLS and FTIR–PLS performed the best for extractives, lignin and xylose, whose residual predictive deviation (RPD) values were all over 3 and indicates the potential for either instrument to provide superior prediction models with NIR performing slightly better. During testing, it was found that more accurate determination of holocellulose content was possible when HPLC was used. Independent chemometric models, for FT-NIR and ATR-FTIR, identified similar functional groups responsible for the prediction of chemical composition and suggested that coupling the two techniques could strengthen interpretation and prediction. [ABSTRACT FROM AUTHOR]

Multifunctional cotton fabric with high electrical conductivity and ultrastrong UV radiation protection properties was successfully fabricated by coating graphene oxide (GO) nanosheet dispersion on fabric surface via vacuum filtration deposition (VFD) method, and then the treated fabric was assembled with polyaniline (PANI) by in-situ chemical polymerization process. The structure and morphological studies showed that the deposition of GO nanosheet is benefit to enhance the uniformity of aniline polymerization on the surface of PANI-GO-cotton fabric. Furthermore, the electrical resistivity of PANI-GO-cotton decrease approximately 10 6 times compared with control cotton, reached at 48.35 Ω cm. PANI-GO-cotton also performed ultrastrong UV radiation protection ability with a UPF value of 445.21, which is superhigher than that of control fabric (UPF rating at 6.86). Moreover, even repeated 10 times water laundering showed nearly no effect on electrical conductivity and UV radiation protection efficiency. [ABSTRACT FROM AUTHOR]

Flexible fabric with remarkable ultraviolet (UV) blocking was deemed as the feasible personal protection to shield human body against external ultraviolet radiation. In this paper, graphene nanoplate (GNP) as a novel UV absorber was utilized to functionalize the surface of cotton fabric at low content (0.05–0.4 wt.%) via pad-dry-cure method. The morphology and structure of the as-obtained modified cotton fabrics were characterized with scanning electron microscope, atomic force microscope, Fourier transform infrared spectroscopy, UV–vis spectroscopy and X-ray photoelectron spectroscopy, respectively. Furthermore, the ultraviolet protection factor (UPF) was applied to evaluate UV blocking properties of the samples. The results indicated that the modified cotton fabric performed ultrastrong protection against UV radiation, up to 10-fold increment of UPF (from 32.71 to 356.74) was endowed only by incorporating graphene nanoplate 0.4 wt.%. [ABSTRACT FROM AUTHOR]

Knit polyester fabric was successively modified and decorated with chitosan layer and polyaniline polymer nanocomposite layer in this paper. The fabric was firstly treated with chitosan to form a stable layer through the pad-dry-cure process, and then the polyaniline polymer nanocomposite layer was established on the outer layer by in situ chemical polymerization method using ammonium persulfate as oxidant and chlorhydric acid as dopant. The surface morphology of coated fabric was characterized by scanning electron microscopy (SEM), and the co-existence of chitosan layer and granular polyaniline polymer nanocomposite was confirmed and well dispersed on the fabric surface. The resultant fabric was endowed with remarkable electrical conductivity properties and efficient water-repellent capability, which also have been found stable after water laundering. In addition, the photocatalytic decomposition activity for reactive red dye was observed when the multifunctional knit polyester fabric was exposed to the illumination of ultraviolet lamp. These results indicated that chitosan and polyaniline polymer nanocomposite could form ideal multifunctional coatings on the surface of knit polyester fabric. [ABSTRACT FROM AUTHOR]

Abstract: Heat transfer between multilayer fibrous materials under unsteady-state conditions is regarded as an intricate and unpredictable process, and the system thermal response with different layer stacking sequences is investigated in this paper. All six possible sequences for three-layer fabrics are measured by an apparatus set up in our lab and simulated by the finite element method, taking account of the effects caused by the internal natural convection and boundary heat loss. It is found that the fabric contacting the hot heat source is the key layer in affecting the system thermal response during the dynamic unsteady-state conditions, and its volumetric heat capacity is the major factor in determining the results. In addition, the effect of the inner natural convection in the multilayer system resulted from the buoyancy is marginal, and negligible under common boundary conditions. In general this study demonstrates that the layer stacking sequences should be considered as an important factor in thermal response while designing a multilayer thermal protective suit. [Copyright &y& Elsevier]

• Flexible membrane was used as free-standing anode for LIBs without additive. • Ultrathin MoS 2 nanosheets composed of less than 5 layers enhance lithium storage performance. • MoS 2 nanosheets on carbon nanofibers is formed, showing flower-like coaxial architecture. • Flexible hybrid material has stable reversible capacity and excellent rate capability in LIBs. [Display omitted] Lithium-ion batteries have high potential to be used as energy storage devices for wearable electronics due to their high energy density, high output voltage and environmental benignity. The increasing demand to develop wearable electronics has aroused great interests for flexible anode of lithium-ion batteries. However, the traditional rigid anode severely hiders further development of lithium-ion batteries in flexible wearable devices. Herein, we demonstrated a flower-like architecture material, in which the layered MoS 2 nanosheets are anchoring on 3D porous carbon nanofibers (CNFs), serving as free-standing anode for LIBs, and this material can be wound at will. The free-standing CNFs were prepared through a facile electrospinning and carbonization process, the MoS 2 nanosheets consist of few MoS 2 ≤ 5 layers and were prepared through a hydrothermal process. Time-dependent experiment illustrated that the flower-like architecture was transformed from bare fibers and tiny particles. Although the polymers were stretched, shrank and covered by MoS 2 nanosheets in the fabrication proess, the membrane still retained excellent flexible from beginning to end. Benefiting from the coaxial structure and synergistic effect, the flexible anode delivered an initial high discharge capacity (938.8 mAh g−1, 0.2 A g−1) and outstanding capacity retention rate at high current density (457.2 mAh g−1, 2 A g−1, 276.3 mAh g−1 after 1000 cycles). Its stability can surpass other flexible MoS 2 -based anodes. Furthermore, the hybrid electrode can maintain superior flexibility and mechanical stability after experiments, guaranteeing a promising future in wearable electronics. This work indicates that the flexible MoS 2 @CNFs can be used as anode for flexible batteries, flexible capacitors and other wearable applications. [ABSTRACT FROM AUTHOR]

• A method for splitting kenaf using microwave combined with lactic acid was proposed. • Fibers have excellent dispersion and suffer minor damage. • The extracted lignin is less damaged and keeps its structural integrity. • Potential for biomass clean production due to low chemicals and time consumption. According to diverse application purposes, different scales of lignocellulosic fibers were obtained from biomass through various preparation conditions. However, the pollution in the fiber separation process restricted the development of the related industry. This research proposed clean fiber separation technology of kenaf bast that combined microwave and lactic acid treatment. The traditional sulfate method was also carried out for comparison. The raw kenaf bast and produced fibers were characterized with wet chemistry analyses, SEM, FTIR, GPC and NMR. The results showed that compared with the traditional method (lignin removal rate 88.3 %, cellulose Mw = 607 kg/mol), the new method had higher lignin removal capacity (94.68 %) and less damage to cellulose (Mw = 1174 kg/mol). TG and NMR analysis showed that the separated crude lignin had a high pyrolysis temperature (350℃), minor structural changes and better uniformity, which was close to natural lignin. In addition, it was calculated that the processing time of the new method was reduced by 82.3 %, which reduced energy loss and waste liquid pollution. This study proved that microwave-assisted lactic acid treatment could separate kenaf fibers efficiently with less damage and pollution. [ABSTRACT FROM AUTHOR]

Developing functional materials integrating multi-tasking oil/water separation performances is significant but challenging for the remediation of large-scale oil spills causing pernicious environmental damages. Herein, a novel Concus Finn Capillary driven oil sorbent (OSCPF) fabricated by aligning superhydrophobic cruciate polyester fibers based on yarn spinning mechanism is designed to realize the clean-up of oil spills and various oil/water mixtures at high speeds. Instantaneous oil diffusion is achieved by abrupt Concus Finn Capillary driven oil-flows along aligned channels. This advance reduces the penetrating time for viscous crude oils by 95.00% comparing with that of non-oriented circular polyester fibers. The OSCPF possess great oil sorption capacity of 54.36–124.71 g/g and can separate oils from immiscible oil/water mixtures, including seawater, soap-water, CuCl 2 -water, and KMnO 4 -water, and surfactant-stabilized O/W emulsions by the way of adsorption with satisfactory separation efficiency (99.41–99.83%). Especially, the OSCPF is effectively used to enclose oil spills to prevent rapid oil diffusion and in-situ continuously collect the spillages from water surface and underwater by pumping device with recovery rates of 15,727–104,227 L·m−2·h−1. Considering the unique structural design, fast oil sorption speed, and low operating cost, this work provides a prospective oil remover addressing the remediation of catastrophic multi-tasking oil/water pollutions. [Display omitted] • Superhydrophobic sorbent with aligned channels is fabricated based on yarn spinning mechanism. • The sorbent contains cruciate polyester fibers with CH 3SiCl3-derived nanofilaments coating. • The Capillary behavior of a surface of cruciate polyester fibers near the vertex change markedly. • Extraordinary efficiency of oil diffusion is achieved by Concus Finn Capillary driven oil-flows. • Large sorption capacity and pumping-driven consecutive oil recovery are demonstrated. [ABSTRACT FROM AUTHOR]

• We demonstrate the first synthesis of cuboid SnSe nanocrystals via a cation exchange. • Nanocrystals exhibit typical indirect bandgap is found in these NCs ranging from 0.9 to 1.2 eV. • Nanocrystals-based anode exhibits a saturated photocurrent density of ∼8.2 mA/cm2. • PEC device has a stable current density of 5.2 mA/cm2 from 2−5 h upon illumination. Tin chalcogenide nanocrystals (NCs) exhibit a wide absorption spectrum with excellent optoelectronic properties. Both Sn and Se are relatively less harmful and less expensive compared to heavy-metals and precious elements. However, it is still a challenge to directly synthesize SnSe NCs without using toxic and sensitive precursors. Here, we use a cation exchange assisted approach to synthesize SnSe NCs that are optically active in the near infrared (NIR). The SnSe NCs have a cuboid shape obtained thorough an orientated growth path. A typical indirect bandgap was found in these NCs ranging from 0.9 to 1.2 eV. As a proof-of-concept, the SnSe NCs were used as light absorbers for photoelectrochemical (PEC) hydrogen evolution, leading to a saturated photocurrent density of 8.2 mA/cm2, a record value for PEC devices using heavy-metal-free NIR NCs. Our results indicate that SnSe NCs of cuboid shape have great potential for use in emerging optoelectronic and photovoltaic devices. [ABSTRACT FROM AUTHOR]

Conventional methods faced challenges in pretreating natural cellulose fibres due to their high energy consumption and large wastewater drainage. This research devised an efficient solid-state pretreatment method for pretreating hemp fibres using ethanolamine (ETA) assisted by microwave (MW) heating. This method produced a notable removal rate of lignin (85.4 %) with the highest cellulose content (83.0 %) at a high solid content (30 %) and low temperature (70 °C). Both FT-IR and XRD analyses indicated that the pretreatment did not alter the structure of cellulose within the hemp fibres but increased crystallinity as the CrI increased from 84 % in raw hemp fibre to 89 % in pretreated fibre. As a result, it produced hemp fibres with impressive fineness (4.6 dtex) and breaking strength (3.81 cN/dtex), meeting the requirement of textile fibre. In addition, an improvement in glucose concentration (15.6 %) was observed in enzymatic hydrolysis of the MW pretreated hemp fibres compared to the fibres pretreated without MW. Furthermore, the FT-IR and NMR data confirmed that the amination of lignin occurred even at low temperature, which contributed to the high lignin removal rate. Thus, this study presents a potentially effective energy-saving, and environmentally sustainable solid-state method for pretreating hemp fibres., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The traditional textile degumming process produces abundant wastewater, which contains a lot of monosaccharides and oligosaccharides. It is of great economic and environmental significance to utilize these carbohydrates in high value. In this study, high performance liquid chromatography (HPLC) was used to analyze the carbohydrate components in kenaf degumming wastewater, and then the production of C-dots using the wastewater was explored. The results showed that the types and content in the degumming wastewater were monosaccharides (glucose, xylose and arabinose) and oligosaccharides (dextran, xylan and araban). The carbohydrate (mainly glucan and xylan) content in wastewater accounted for 91.16 % of the total carbohydrates weight loss in kenaf degumming process. By using hydrolysis and hydrothermal reaction on kenaf degumming wastewater, blue-green carbon dots (C-dots) with good performance were prepared and successfully applied to anti-counterfeiting printing. In particular, the as-prepared C-dots prepared from kenaf degumming wastewater with urea added (WUC-dots) showed an excitation-dependent photoluminescence (PL) spectrum and quantum yield (QY) of 2.4 % in aqueous solution. The fluorescent code exhibited a clear outline, excitation-tunable color and good stability, showing a great potential for anti-counterfeiting system., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The catalytic conversion of cellulose to lactic acid (LA) has garnered significant attention in recent years due to the potential of cellulose as a renewable and sustainable biomass feedstock. Here, a series of Au/W-ZnO catalysts were synthesized and employed to transform cellulose into LA. Through the optimization of reaction parameters and catalyst compositions, we achieved complete cellulose conversion with a selectivity of 54.6% toward LA over Au/W-ZnO at 245 °C for 4 h. This catalyst system also proved effective at converting cotton and kenaf fibers. Structural and chemical characterizations revealed that the synergistic effect of W, ZnO, and Au facilitated mesoporous architecture generation and the establishment of an adequate acidic environment. The catalytic process proceeded through the hydrolysis of cellulose to glucose, isomerization to fructose, and its subsequent conversion to LA, with glucose isomerization identified as the rate-limiting step. These findings provide valuable insights for developing high-performance catalytic systems to convert cellulose.

The utilization of Cu-based catalysts in CO 2 conversion into valuable chemicals is of significant interest due to their potential in mitigating greenhouse gas emissions. However, the controllable design of Cu-based catalysts and the regulation of their mechanism remain challenging. In this study, a series of efficient Cu/L catalysts were prepared for this process, and the intrinsic influencing factors on the reaction routes were systematically revealed. Various techniques revealed that Cu particles in L-supported catalysts exhibited higher dispersion and formed Cu-O(OH)-K interfacial sites. However, with increasing Cu loading, the dispersion of Cu particles and the percentage of Cu-O(OH)-K interfaces decreased. Kinetic investigations revealed that the adsorption configuration and electronic structure of Cu species codetermined the reaction pathways and resulting selectivity. Cu/L catalysts possessing Cu-O(OH)-K interfaces and small particles demonstrated the preferential formation of formate species, promoting methanol formation. However, larger Cu particles generated carboxylate intermediates, resulting in higher CO selectivity..

The development of high-efficiency non-precious metal electrocatalysts for alkaline electrolyte hydrogen evolution reactions (HER) is of great significance in energy conversion to overcome the limited supply of fossil fuels and carbon emission. Here, a highly active electrocatalyst is presented for hydrogen production, consisting of 2D CoSe 2 /Co 3 S 4 heterostructured nanosheets along Co 3 O 4 nanofibers. The different reaction rate between the ion exchange reaction and redox reaction leads to the heterogeneous volume swelling, promoting the growth of 2D structure. The 2D/1D heteronanostructures enable the improved the electrochemical active area, the number of active sites, and more favorable H binding energy compared to individual cobalt chalcogenides. The roles of the different composition of the heterojunction are investigated, and the electrocatalysts based on the CoSe 2 /Co 3 S 4 @Co 3 O 4 exhibited an overpotential as low as 165 mV for 10 mA cm -2 and 393 mV for 200 mA cm -2 in 1 m KOH electrolyte. The as-prepared electrocatalysts remained active after 55 h operation without any significant decrease, indicating the excellent long-term operation stability of the electrode. The Faradaic efficiency of hydrogen production is close to 100% at different voltages. This work provides a new design strategy toward Co-based catalysts for efficient alkaline HER., (© 2023 Wiley-VCH GmbH.)

Water pollution, which is caused by leakage of oily substances, has been recognized as one of the most serious global environmental pollutions endangering the ecosystem. High-quality porous materials with superwettability, which are typically constructed in the form of aerogels, hold huge potential in the field of adsorption and removal of oily substances form water. Herein, we developed a facile strategy to fabricate a novel biomass absorbent with a layered tubular/sheet structure for efficient oil/water separation. The aerogels were fabricated by assembling hollow poplar catkin fiber into chitosan sheets using a directional freeze-drying method. The obtained aerogels were further wrapped with -CH 3 -ended siloxane structures using CH 3 SiCl 3 . This superhydrophobic aerogel (CA ≈ 154 ± 0.4°) could rapidly trap and remove oils from water with a large sorption range of 33.06-73.22 g/g. The aerogel facilitated stable oil recovery (90.07-92.34%) by squeezing after 10 sorption-desorption cycles because of its mechanical robustness (91.76% strain remaining after 50 compress-release cycles). The novel design, low cost, and sustainability of the aerogel provide an efficient and environmentally friendly solution for handling oil spills.

Developing ceramic nanofibrous membranes for the thermal insulation layer of firefighting protective clothing is vital. However, previous ceramic nanofibrous membranes were brittle and easy to break during service in high-temperature environments. The lack of elastic and compressible properties has limited the high-end applications of ceramic nanofibrous membranes. In this work, elastic and compressible Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes were fabricated via sol-gel electrospinning and calcination in air at different temperatures. The as-fabricated Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes can maintain excellent elasticity and compressibility in the temperature ranging from -196 to 1400 °C. Moreover, they have low thermal conductivity and high working temperatures. These favorable characteristics make the Al 2 O 3 /ZrO 2 /La 2 O 3 nanofibrous membranes a promising candidate for the thermal insulation layer of firefighting protective clothing., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Air pollution induced by pathogenic particulate matter (PM) has posed a serious threat to public health worldwide. Advanced air filters are thus required, not only exhibiting high PM capture efficiency, low breathing resistance, and high internal moisture transferring performance but also isolating and inactivating external pathogenic aerosols. In this study, we demonstrated a facile approach to construct a biomimetic fibrous leaf-vein membrane with unidirectional water penetration and effective antibacterial PM filtration by one-step electrospinning of poly(vinylidene fluoride) (PVDF)-based multilayer nanofibers. With ultrathin fibers penetrating the skeletal framework of bimodal thick fibers, the membranes showed gradient interconnected porous structures and achieved a highly efficient and stable (in an acid and alkali environment) PM 0.3 interception (>99.98%) with low air drag (51-71 Pa). In addition, the gradient narrow pores of the membranes contributed to a gradient higher hydrophilicity. The subsequent unidirectional water motion effectively isolates pathogenic aerosols typically generated by external individuals or ultrafast water penetration from the inverse face. Moreover, the membranes demonstrated an antibacterial efficacy (>99.99%) in a 5 min contact, inactivating the intercepted airborne pathogens efficiently. The test results proved that the proposed membranes were promising advanced air filters for respirator applications.

Large scale solar-driven hydrogen production is a crucial step toward decarbonizing society. However, the solar-to-hydrogen (STH) conversion efficiency, long-term stability, and cost-effectiveness in hydrogen evolution reaction (HER) still need to be improved. Herein, an efficient approach is demonstrated to produce low-dimensional Pt/graphene-carbon nanofibers (CNFs)-based heterostructures for bias-free, highly efficient, and durable HER. Carbon dots are used as efficient building blocks for the in situ formation of graphene along the CNFs surface. The presence of graphene enhances the electronic conductivity of CNFs to ≈3013.5 S m -1  and simultaneously supports the uniform Pt clusters growth and efficient electron transport during HER. The electrode with a low Pt loading amount (3.4 µg cm -2 ) exhibits a remarkable mass activity of HER in both acidic and alkaline media, which is significantly better than that of commercial Pt/C (31 µg cm -2  of Pt loading). In addition, using a luminescent solar concentrator-coupled solar cell to provide voltage, the bias-free water splitting system exhibits an STH efficiency of 0.22% upon one-sun illumination. These results are promising toward using low-dimensional heterostructured catalysts for future energy storage and conversion applications., (© 2022 Wiley-VCH GmbH.)

Using tubular kapok fibers (KF) and sodium alginate (SA) as the natural building block, we put forward a novel oriented neurovascular network-like superhydrophobic aerogel with robust dry and wet compression resilience by directional freeze-drying and chemical vapor deposition. In the block, SA forms aligned channel structures providing space for rapid oil transmission, while KF serves as vascular-like capillaries acting as instant "tentacle" to capture the tiny oil droplets in water, facilitating fascinating oil capture efficiency for versatile oil/water separation, The aerogel after dry and wet compression (under a strain of 60%) can recover 96.0% and 97.3% its original, respectively, facilitating stable oil recovery (81.1-89.8%) by squeezing, high separation efficiency (99.04-99.64%) and permeation flux separating oil contaminants from water. A pump-supported experiment shows the aerogel efficiently collecting oil contaminants from the water's surface and bottom by 11503-25611 L·m -2 ·h -1 . Particularly, the aerogel as robust oil droplets captor facilely achieves isolation of 99.39-99.68% emulsified oils from oil/water emulsions by novel oil trapping mechanism which simply involves exerting kinetic energy on emulsified oils through repeated oscillation, potentially indicating a simple and efficient alternative to membrane-based oily wastewater remediation via filtration., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Environmentally friendly face masks with high filtration efficiency are in urgent need to fight against the COVID-19 pandemic, as well as other airborne viruses, bacteria and particulate matters. In this study, coaxial electrospinning was employed to fabricate a lithium chloride enhanced cellulose acetate/thermoplastic polyurethanes (CA/TPU-LiCl) face mask nanofiber filtration membrane, which was biodegradable and reusable. The analysis results show that the CA/TPU-LiCl membrane had an excellent filtration performance: when the filtration efficiency reached 99.8%, the pressure drop was only 52 Pa. The membrane also had an outstanding reusability. The filtration performance maintained at 98.2% after 10 test cycles, and an alcohol immersion disinfection treatment showed no effect on its filtration performance. In summary, the CA/TPU-LiCl nanofiber membrane made in this work is a promising biodegradable and reusable filtration material with a wide range of potential applications, including high-performance face mask.

This paper presents a study of the bending flexibility of fully covered biodegradable polydioxanone biliary stents (FCBPBs) developed for human body. To investigate the relationship between the bending load and structure parameter (monofilament diameter and braid-pin number), biodegradable polydioxanone biliary stents derived from braiding method were covered with membrane prepared via electrospinning method, and nine FCBPBSs were then obtained for bending test to evaluate the bending flexibility. In addition, by the finite element method, nine numerical models based on actual biliary stent were established and the bending load was calculated through the finite element method. Results demonstrate that the simulation and experimental results are in good agreement with each other, indicating that the simulation results can be provided a useful reference to the investigation of biliary stents. Furthermore, the stress distribution on FCBPBSs was studied, and the plastic dissipation analysis and plastic strain of FCBPBSs were obtained via the bending simulation., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Two types of PdCu 2 nanoparticles were prepared through one-pot synthesis and a two-step reducing process, named as PdCu 2 -1 and PdCu 2 -2, respectively. The morphology and structure of as-prepared samples were investigated by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and inductively coupled plasma-optical emission spectrometry. Results showed that more Pd atoms were buried in the inside of PdCu 2 -1, whereas more available Pd sites were distributed on the surface of PdCu 2 -2. The electrochemical measurements indicated that both PdCu 2 -1 and PdCu 2 -2 nanoparticles showed a higher electrocatalytic activity than that for pure Pd nanoparticles. In particular, PdCu 2 -2 predictably exhibited a better stability and durability as well as a lower onset potential and a higher catalytic current density than that of PdCu 2 -1 toward ethanol oxidation in alkaline media. On the basis of these studies, the formation mechanisms of both the PdCu 2 catalysts and the relationship between their structure and properties were discussed in this paper.

In this study, a wet spinning method was applied to fabricate regenerated cellulose fibers filled with low graphene loading which was systematically characterized by SEM, TEM, FTIR and XRD techniques. Subsequently, the mechanical and thermal properties of the resulting fibers were investigated. With only 0.2 wt% loading of graphene, a ∼ 50% improvement of tensile strength and 25% enhancement of Young's modulus were obtained and the modified Halpin-Tsai model was built to predict the mechanical properties of composite fibers. Thermal analysis of the composite fibers showed remarkably enhanced thermal stability and dynamic heat transfer performance of graphene-filled cellulose composite fiber, also, the presence of graphene oxide can significantly enhance the thermal conductivity of the composite fiber. This work provided a facile way to improve mechanical and thermal properties of regenerated cellulose fibers. The resultant composite fibers have potential application in thermal insulation and reinforced fibrous materials., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Kenaf has a high content of gum that is difficult to remove. Traditional chemical degumming process causes serious environmental pollution. To solve the problem, we developed a new method to degum kenaf. We pretreated the kenaf with steam explosion followed by ultrasonic treatment. We chose the single factor tests to select the ultrasonic frequency, sodium hydroxide concentration and processing time. Combined with orthogonal tests, we found that the optimum conditions were as follows: ultrasonic frequency was 28 kHz, sodium hydroxide concentration was 2%, and processing time was 60 min. Under these conditions, the residual gum of kenaf fiber was 9.72% and the fineness was 139.45 N(m). Steam explosion combined with ultrasonic method is effective in degumming of kenaf.