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[Display omitted] • 2D laminate films prepared via a hybrid dimensional design of Chiber, MWCNT, and rGO. • The 2D film achieves a high water evaporation rate of 2.10 kg·m−2·h−1 under one sun. • 0.45 V of electricity is generated in the saturated NaCl solution during evaporation. • Lamellar structure and nanopores supply good water transport and thermal management. • Molecular-level elucidation of electricity generation through MD simulation. Emerging water purification technology, known as interfacial solar steam generation (ISSG), has been rapidly developing in recent years. ISSG offers a promising solution to address both freshwater shortage and energy demand by simultaneously producing freshwater and electricity. This is achieved through the combination of microporous films and highly efficient photothermal materials. In this study, we have developed a composite film using a 2D material, reduced graphene oxide (rGO), and a combination of 1D materials, chitin fiber@multi-walled carbon nanotube (Chiber@CNT). Through a hybrid dimensional design, these materials' advantages are integrated, resulting in a composite film with a distinct laminar porous structure and excellent broadband absorption. Notably, under 1 kW·m−2 sunlight irradiation, the composite film achieves a water evaporation flux of 2.10 kg·m−2·h−1 with a photothermal conversion efficiency of 75.79%. In addition, by utilizing an energy-harvesting strategy based on natural water evaporation in porous nanomaterials for power generation, the composite film successfully enables the simultaneous production of freshwater and electricity. Its output voltage reaches 0.39 V in a 3.5 wt% NaCl solution. Furthermore, the film's output voltage varies with the concentration of NaCl, increasing from 0.26 V (in deionized water) to 0.45 V (in the saturated NaCl solution). Molecular dynamic simulation results indicate that the enhanced power generation can be attributed to the difference in interatomic interaction strength between ions and hydrophilic functional groups in chitin fiber (Chiber). This finding provides a deep physical mechanism and opens up possibilities for the film's application in highly concentrated salt solutions. [ABSTRACT FROM AUTHOR]

In this paper we establish a new on-diagonal lower estimate of heat kernels for connected, weighted, locally finite graphs. The result is then used to deal with the nonexistence of global solutions for a semilinear heat equation on locally finite graphs. Our results provide remarkable improvements to the work that was done recently by Lin and Wu (2017) [8,18]. [ABSTRACT FROM AUTHOR]

Let G = ( V , E ) be a simple, finite, connected, weighted graph satisfying curvature condition C D E ′ ( n , 0 ) and polynomial volume growth V ( x , r ) ≤ c 0 r m , Δ η be the normalized Laplacian. In this paper we prove that the semilinear heat equation u t = Δ η u + u 1 + α on G has no non-negative global solutions for any bounded, non-negative and non-trivial initial value in the case of m α = 2 . The obtained result provides a significant complement to the work that was done recently by Lin and Wu (2017) concerning the existence and nonexistence of global solutions for the semilinear heat equation on graphs. [ABSTRACT FROM AUTHOR]

In this work, the TiO 2 nanorod arrays (TNAs), TNAs/Cu 2 O-10CYC, and TNAs/Cu 2 O-30CYC composites photo-catalysts for solar water splitting anode was successfully prepared via cyclic impregnation growth method. The structure, surface morphology and element chemical states have been investigated and discussed in detail. The UV–vis and PL results confirm that interaction has been formed between TNAs and Cu 2 O in the composite photo-catalysts and the TNAs/Cu 2 O composites exhibit broad spectrum absorption. Three factors affecting on the enhancement of solar light hydrogen production efficiency, e.g. enhanced UV-light absorption in solar spectrum, massive charge carrier generation and improved surface-interface reaction due to the absorbing visible light by the narrow band gap Cu 2 O and the injecting electrons into TiO 2 conduction band, are proposed based on the experimental results. The TNAs/Cu 2 O-10CYC composite samples exhibit highest enhanced photocatalytic activities in the hydrogen production, which H 2 evolution efficiency is about 4-fold higher than that of pure TNAs. It indicates that the efficient photo generated electron-hole transformation and separation in TNAs/Cu 2 O-10CYC composite sample leads to the improvement of photocatalytic performance. The present study provides a new light to prepare TNAs/Cu 2 O of novel configuration with promising potential applications. [ABSTRACT FROM AUTHOR]

We have coupled gold nanoparticles (AuNPs) with silver nanoparticles (AgNPs) to assemble a plasmonic sensing platform for colorimetric detection of glucose. In this system, small AuNPs (~ 4 nm) can act as glucose oxidase (GOD) mimic enzyme to catalytically oxidize glucose in the presence of oxygen, producing hydrogen peroxide, which dissolves AgNPs to lead the color changes. Glucose can be detected not only by naked eyes (from yellow to red) but also by spectrophotometer in the concentration range of 5–70 μM, with detection limit of 3 μM. More importantly, we found that l -cysteine added in the system can markedly improve the selectivity for the detection of glucose. The proposed method was used to application for the detection of glucose in human serum with satisfactory results. This system is simple and low cost without using any enzymes and organic chromogenic agents. [ABSTRACT FROM AUTHOR]

Designing nanoscale photocatalysts to improve photocatalytic efficiency is a popular research topic. However, for wide application and friendly environment, achieving good dispersion and multiple recycling of photocatalysts at the nanoscale remains challenging. Herein, a general bottom-up assembly method is proposed for designing a class of two-dimensional lamellar membranes (2DLMs) for photocatalytic applications. A bismuth oxychloride (BiOCl) nanosheet (BN) was used as a demo photocatalyst to construct a 2DLM via self-stacking. The designed BiOCl membrane (BM) exhibited excellent physical properties including flexibility, mechanical strength (tensile strength = 15.75 MPa, fracture strain = 0.056%), and translucence, as well as superior photocatalytic performance with excellent recycling stability and reusability. The photocatalytic hydrogen evolution performance of BM was 2.5-fold that of BN particles dispersed in an aqueous solution. Further theoretical calculations revealed that a BM with appropriately sized nanochannels can accelerate water transport, and the main horizontal channel size of the BM (3.13 nm) is very close to the size of the ideal water transport nanochannel. Furthermore, the confined internal space reduces the number of hydrogen bonds for water molecules within the nanochannels, thereby enhancing the interfacial reaction rate and photocatalytic efficiency. This study presents a simple bottom-up assembly method to design photocatalysts with further improved performance. [Display omitted] • A general strategy to design lamellar membrane (LM) for photocatalytic is proposed. • The nanochannels speed up water transport and facilitate photocatalytic reaction. • The hydrogen bonds among water molecules inside nanochannels are weakened. • Photocatalytic H 2 evolution activity of BiOCl LM is 2.5-fold that of its particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synthesis strategy of GSMs is discussed and analyzed. • The effect of different nanomaterials on the layer spacing of GSMs was expounded. • The removal of pollutants in water by GSMs is reviewed. • The challenges and potential of future GSMs are highlighted. Membrane separation technology has attracted increasing research interest and plays an important role in industrial wastewater treatment, urban sewage purification, oil and water separation, hence the search for perfect separation membrane is being given serious consideration. Graphene and its derivatives have significant potential applications owing to their atomic thickness, adjustable physicochemical properties and unique two-dimensional interlayer channels. It is considered as attractive components for the construction of high-performance separation membranes, which promises to break the trade-off between permeability and selectivity, leading to the ultimate separation. In this review, the current strategies that are promising in the synthesis and fabrication of graphene separation membranes (GSMs) are introduced and extensively discussed. Further the research progresses of imbedding nanoparticles in GSMs in recent years are reviewed, and the strategies of constructing GSMs with different interlayer spacing to improve membrane efficiency are explored. Finally, the application of GSMs in water purification and seawater desalination is demonstrated, highlighting some outstanding challenges associated with future perspectives in this field which would inspire the research design of next-generation GSMs. [ABSTRACT FROM AUTHOR]

• Comprehensive utilization of solar energy to get hydrogen energy and fresh water was studied. • 2D lamellar membrane based on the semiconductor BiOCl nanosheet was designed. • PHE and PWE were closely related to the light-to-thermal conversion and water state. • The PWE rate of BOC-CNF@CNT lamellar membrane was up to 2.05 kg·m−2·h−1. Solar energy can help solve the energy and water shortage crisis. Developing a single material that can exhibit both photocatalytic hydrogen evolution (PHE) and photothermal water evaporation (PWE) represents a new concept to simultaneously realize green energy and fresh water supply. In this study, a series of 2D lamellar membranes (2DLMs) based on a conventional semiconductor BiOCl nanosheet was designed as an ensemble, and its combined application for PHE and PWE was explored, in which cellulose nanofibers (CNFs), carbon nanotubes (CNTs), and a self-assembly of CNF@CNT were also used. The PHE and PWE efficiencies are closely related to the conversion of solar energy and the state of the water molecules. Owing to the high light-to-thermal conversion, enhanced water transfer, and the low evaporation enthalpy of confined water, a composite made of BiOCl and CNF@CNT 2DLM (BOC-CNF@CNT) could rapidly reach a surface temperature of 46.6 °C, with its PWE rate reaching up to 2.05 kg·m−2·h−1. Moreover, owing to the high photogenerated carrier transport, strong photothermal effect, and the action of confined water, the PHE rate of BOC-CNF@CNT is 1.99-fold that of the composite made of BiOCl and CNF 2DLM (BOC-CNF) and 1.42-fold that of the composite made of BiOCl and CNT 2DLM (BOC-CNT). This work provides a new and effective strategy for a comprehensive utilization of solar energy to simultaneously produce clean hydrogen and fresh water. [ABSTRACT FROM AUTHOR]

Short-chain fatty acids (SFCAs) exhibit diverse functions from kidneys to human health and diseases, and also could exert their roles in post-translational modifications (PTMs). Nowadays, novel short-chain lysine acylations derived from SFCAs have attracted more attentions, including propionylation, butyrylation, 2-hydroxyisobutyrylation, β-hydroxybutyrylation, malonylation, succinylation, crotonylation, glutarylation, lactylation, etc. These acylations have multiple physiological effects on many diseases, which also contribute to kidney pathophysiology. Here, we summarize the role of the currently novel PTMs in the kidneys for human health and diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

With the increasing environmental and ecological problems caused by petroleum-based packaging materials, the focus has gradually shifted to natural resources for the preparation of functional food packaging materials. In addition to biodegradable properties, nanocellulose (NC) mechanical properties, and rich surface chemistry are also fascinating and desired to be one of the most probable green packaging materials. In this review, we firstly introduce the recent progress of novel applications of NC in food packaging, including intelligent packaging, nano(bio)sensors, and nano-paper; secondly, we focus on the modification techniques of NC to summarize the properties (antimicrobial, mechanical, hydrophobic, antioxidant, and so on) that are required for food packaging, to expand the new synthetic methods and application areas. After presenting all the latest advances related to material design and sustainable applications, an overview summarizing the safety of NC is presented to promote a continuous and healthy movement of NC toward the field of truly sustainable packaging. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D BiOCl lamellar membrane with CNFs is constructed for photocatalyst. • Hydrogen evolution rate of BiOCl/CNF 2DLM is 4.7-times that of the BiOCl nanosheets. • Experimental and theoretical analyses revealed the effect of CNFs on photocatalysis. • CNFs can regulate hydrogen bonds networks of confined water. • Confined water promotes the release of H+ from H 2 O. Photocatalytic hydrogen evolution (PHE) is a sustainable alternative for generating green and clean energy. However, it requires the use of nanoscale photocatalysts, whose applicability is limited by their poor reusability and proton release from water molecules. Herein, a porous two-dimensional lamellar membrane (2DLM) photocatalyst was fabricated from bismuth oxychloride (BiOCl) nanosheets (BNs) and cellulose nanofibers (CNFs) via layer-by-layer self-assembly. The hybridization of the CNFs with the BNs improved the PHE rate of the resulting BiOCl/CNFs membrane (BCM). The optimal PHE rate was observed for a CNF content of 3.2 wt% and was 4.7-times that of raw BNs dispersed in an aqueous solution alone and 1.85-times that of the BiOCl membrane (BM). Moreover, the PHE rate remained unchanged even after 10 discontinuous cycles for a total time of 60 h. Comprehensive experimental characterization and molecular dynamics simulations confirmed that the introduction of the CNFs effectively regulated the hydrogen bond network of the confined water molecules, thus improving the efficiency of the conversion of H 2 O into H 2. Meanwhile, the optimization of the nanochannel sizes of the BNs by the hybridized CNFs accelerated water transport within the nanochannels. The 2DLM also showed excellent mechanical strength, flexibility, and translucence. This strategy of fabricating 2DLMs using a nanosheet photocatalyst and CNFs not only results in improved PHE performance but also should also aid the development of stable and reusable photocatalysts for other industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Based on the residual energy recovery in the electromagnetic emission scenario, the 30C pulse charging cycle experiments of LiFePO 4 batteries customized for electromagnetic emission at different charging temperatures were carried out to study the influence of charging temperature on battery aging. By adjusting the ambient temperature, heat dissipation conditions, and rest time, we studied the battery aging process at the average charging temperatures of 16 °C, 21 °C, 26 °C, 30 °C and 35 °C. Experimental results show that increasing charging temperature can significantly delay battery aging and prolong battery cycle life. In addition, when the average charging temperature is lower than 30 °C, the battery shows nonlinear aging; when the average charging temperature is higher than 30 °C, the battery shows linear aging in the early stage of cycling and nonlinear aging at the end of the cycle. The results of differential capacity analysis (DCA) show that the loss of lithium inventory is the primary aging mode of the battery and did not change with charging temperature. The aging mechanism of the battery under high-rate pulse charging was studied through multiscale post-test analysis. Analysis results showed that with the increase of charging temperature, the area of lithium-plating area decreases, and the thickness of SEI film increases. It can be inferred that when the average charging temperature is lower than 30 °C, lithium plating is the primary aging mechanism of the LiFePO 4 battery customized for electromagnetic emission. When the average charging temperature is higher than 30 °C, the growth of SEI film is the primary aging mechanism of the battery. [ABSTRACT FROM AUTHOR]

An experiment was carried out to study the buckling and post-buckling behavior of stiffened composite curved panel under shear and in-plane bending. A test fixture was designed uniquely which was suitable for curved panel subjected to shear or shear and in-plane bending. The results showed that this kind of fixture was feasible. The strain data were recorded by strain gauges. The out-of-plane displacement field was characterized by a 3D digital speckle system. The stability of stiffened composite curved panel subjected to shear and in-plane bending was analyzed by the obtained data. Finite element method (FEM) was used. The influence of transverse frames on the stability of stiffened curved panel was further studied by FEM. Good correlation between experimental and FEM analysis was obtained. The fixture and test method used in this paper provide a reference to the study of curved panel subjected to shear or shear and in-plane bending. [ABSTRACT FROM AUTHOR]