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A method for direct electrochemical conversion of lignin to short-chain carboxylic acids is developed.

Flexible aqueous energy storage devices with high security and flexibility are crucial for the progress of wearable energy storage. Particularly, aqueous rechargeable Ni-Fe batteries owning a large theoretical capacity, low cost and outstanding safety characteristics have emerged as a promising candidate for flexible aqueous energy storage devices. Herein, Cu-doped Fe3O4 (CFO) with 3D coral structure was prepared by doping Cu2+ based on Fe3O4 nanosheets (FO). Furthermore, the Fe-based anode material (CFPO) grown on carbon fibers was obtained by reconstructing the surface of CFO to form a low-crystallization shell which can enhance the ion transport. Excitingly, the newly developed CFPO electrode as an innovative anode material further exhibited a high capacity of 117.5 mAh g−1 (or 423 F g−1) at 1 A g−1. Then, the assembled aqueous Ni-Fe batteries with a high cell-voltage output of 1.6 V deliver a high capacity of 49.02 mAh g−1 at 1 A g−1 and retention ratio of 96.8% for capacitance after 10 000 continuous cycles. What's more, the aqueous quasi-solid-state batteries present a remarkable maximal energy density of 45.6 Wh kg−1 and a power density of 12 kW kg−1. This work provides an innovative and feasible way and optimization idea for the design of high-performance Fe-based anodes, and may promote the development of a new generation of flexible aqueous Ni-Fe batteries.

A CdS@MoS2 composite photocatalyst exhibits excellent photocatalytic activity to replace noble metals by constructing a n–n heterojunction.

Hybrid supercapacitors have the advantages of fast charging and discharging and long service life, which are an efficient and practical energy storage device. Therefore, the design of hybrid supercapacitors is the focus of current research. In this paper, the silver modified spinel NiCo2S4 nanorods (Ag2S-NiCo2S4/CF) are synthesized by an efficient and economical method, which has excellent electrochemical performance. The Ag2S-NiCo2S4/CF shows a high specific capacity of 179.7 mAh g−1 at current density of 1 A g−1, and excellent rate capability (capacitance retention of ~87% at 20 A g−1). The corresponding Ag2S-NiCo2S4/CF//AC/CF hybrid supercapacitor is assembled by Ag2S-NiCo2S4/CF as the positive electrode, which can provide an energy density of 35.978 Wh kg−1 at a high-power density of 800 W kg−1 and has significant cyclic stability (~80% of the initial capacitor after ~9600 cycles). Therefore, Ag2S-NiCo2S4/CF material is a promising electrode material that can be applied to hybrid supercapacitors.

In power storage technology, ion exchange is widely used to modify the electronic structures of electrode materials to stimulate their electrochemical properties. Here, we proposed a multistep ion exchange (cation exchange and anion exchange) strategy to synthesize amorphous Ni-Co-S and β-Co(OH)2 hybrid nanomaterials with a hollow polyhedron structures. The synergistic effects of different components and the remarkable superiorities of hollow structure endow Ni-Co-S/Co(OH)2 electrode with outstanding electrochemical performance, including ultra-high specific capacity (1440.0 C/g at 1 A/g), superior capacitance retention rate (79.1% retention at 20 A/g) and long operating lifespan (81.4% retention after 5000 cycles). Moreover, the corresponding hybrid supercapacitor enjoys a high energy density of 58.4 Wh/kg at the power density of 0.8 kW/kg, and a decent cyclability that the capacitances are maintained at 80.8% compared with the initial capacitance. This research presents a high-performance electrode material and provides a promising route for the construction of electrode materials for supercapacitors with both structural and component advantages.

Two-dimensional (2D) carbon nitride (CN) photocatalysts are attracting extensive attention owing to their excellent photocatalytic properties. In this study, we successfully prepared CN materials with heterogeneous structures via hydrothermal treatment, high-temperature roasting, ball milling, sintering, and other processes. Benefitting from interface interactions in hybrid architectures, the CN photocatalysts exhibited high photocatalytic activity. The rate of hydrogen production using these CN photocatalysts reached 17028.82 μmol h−1 g−1, and the apparent quantum efficiency was 11.2% at 420 nm. The ns-level time-resolved photoluminescence (PL) spectra provided information about the time-averaged lifetime of fluorescence charge carriers; the lifetime of the charge carriers causing the fluorescence of CN reached 9.99 ns. Significantly, the CN photocatalysts displayed satisfactory results in overall water splitting without the addition of sacrificial agents. The average hydrogen and oxygen production rates were 270.95 μmol h−1 g−1 and 115.21 μmol h−1 g−1 in 7 h, respectively, which were promising results for the applications of the catalysts in overall water splitting processes. We investigated the high efficiency of the prepared CN photocatalysts via a series of tests (UV-vis diffuse reflectance spectroscopy, photocurrent response measurements, PL emission spectroscopy, time-resolved PL spectroscopy, and Brunauer-Emmett-Teller analysis). Furthermore, the Mott-Schottky plot and current-voltage curve were acquired via electrochemical tests. The fabricated CN photocatalyst had a small p-n junction in its heterogeneous structure, which further enhanced its photocatalytic efficiency. Therefore, this work can promote the development of CN photocatalysts.

CdS is widely used in the field of photocatalysis owing to its excellent photocatalytic H2 evolution (PHE) activity, but the photocatalytic stability of CdS is inhibited because of the drawback of photocorrosion. Under light, the introduction of WS2 cocatalysts induces the growth of layered CdS on the WS2 nanosheets. Through the photocatalytic activity measurement, after adding ultrathin WS2 nanosheets, the amount of H2 released can reach 139.15 mmol g−1 after 7 h, which is 11.3 times higher than that of pure CdS nanoparticles. Furthermore, these composites illustrate excellent light absorption performance in the near-infrared region. A heterojunction is formed between WS2 and CdS under light, which greatly promotes the mobility of interface carriers and limits the recombination of photogenerated carriers. The hydrogen evolution output remains stable after 42 h, and the photocorrosion problem is effectively suppressed. In this work, we provide an effective and simple method to improve photocatalytic activity and stability, which is beneficial to the practical development of photocatalysis.

Carbon nitride (CN) photocatalysts have attracted much attention due to their excellent photocatalytic properties. And hydrothermal fluorination is a common method to improve the photocatalytic effect of CN photocatalyst. Here, the influence of the band gap was first revealed of fluorination and hydroxylation of CN photocatalyst based on the first theoretical principle. Here, the effect of fluorination and hydroxylation on the CN band gap was discussed for the first time using the first theoretical principle. With F atoms and OH doping, the band gap of CN was significantly improved, conduction band and valence band moved up. Then, F CN photocatalyst with F atoms and OH was successfully synthesized by a hydrothermal fluorinated method. Next, the reasons why F CN photocatalyst was more effective than that of traditional CN photocatalyst were fully discussed. From the photocatalytic effect of photocatalyst (12,593.2 μmol g−1 h−1 to the morphology (super-small nanosheets), structure (homojunctions), composition (metal‐free), specific surface area (54.1 m2/g), visible light absorption response (AQE is 10.9% at 420 nm) and photo-induced carrier life (14.13 ns). Therefore, this work has a great guiding effect on the development of CN photocatalyst.

g-C3N4 have been widely used in the fields of photocatalytic hydrogen production, photocatalytic degradation of dyes and oxidative degradation of toxic gases due to their excellent performance. It has attracted extensive attention in recent years due to its highly efficient photocatalytic capacity of hydrogen generation, water oxidation, carbon dioxide reduction and degradation of organic pollutants. Because of the abundant carbon and nitrogen composition of the earth, large-scale production and industrial applications of this material are possible. The modification of this material makes its performance more excellent so that this new material can obtain a steady stream of vitality. These outstanding works have become important materials and milestones on the road to mankind’s photocatalytic hydrogen production. This review will begin with the basic idea of designing, synthesizing and improving g-C3N4 based photocatalytic materials, and introduce the latest development of g-C3N4 photocatalysts in hydrogen production from four aspects of controlling the carbon/nitrogen ratio, morphology, element doping and heterojunction structure of g-C3N4 materials.

The use of cheap and efficient electrocatalyst for the production of hydrogen is the key to solving the current energy crisis. Herein, we used a two-step hydrothermal process to fabricate noble-metal-free 3D net-like Ni

The successful preparation and application of graphene shows that it is feasible for the materials with a thickness of a single atom or few atomic layers to exist stably in nature. These materials can exhibit unusual physical and chemical properties due to their special dimension effects. At present, researchers have made great achievements in the preparation, characterization, modification, and theoretical research of 2D materials. Because the structure of 2D materials is often similar, it has a certain degree of qualitative versatility. Besides, 2D materials often carry good catalytic performance on account of their more active sites and adjustable harmonic electronic structure. In this review, taking 2D materials as examples [graphene, boron nitride (h-BN), transition metal sulfide and so on], we review the crystal structure and preparation methods of these materials in recent years, focus on their photocatalyst properties (carbon dioxide reduction and hydrogen production), and discuss their applications and development prospects in the future.

The human DEC subfamily contains two highly conserved members belonging to basic helix-loop-helix (bHLH) transcription factors. This conserved family is spread widely among various species with the function of regulating various crucial molecular signaling pathways. Due to the significance of DECs for important biological processes, their relationship with diseases and the lack of experimentally proven structures, we have implemented a comparative modeling for the bHLH region of DECs as homodimers with themselves and heterodimers with HES-1. Three mutants with predicted roles in reducing intramolecular binding (H57A, R65A, and LL7879AA in DEC1 and LL7071AA in DEC2) were investigated on DEC monomers. Molecular dynamics (MD) simulations were also employed to evaluate the behavior of the mutant molecules in aqueous solution. The monomer was divided into subregions for accurate investigation. The fluctuation in the basic region of mutants was higher than that of wild-type molecules. The binding energy value between protein and DNA obviously increased in the homodimer harboring R65A mutants, which led to more unstable status between protein and DNA. Thus, the mutant R65A interfered DNA-binding affinity. A study on the spatial structures of wild-type and mutant DECs may facilitate functional prediction for mutation effects and dynamic behavior under various conditions and may ultimately help in targeted drug design.

Uniformly lamellar MoS2 nanoflowers have successfully grown on the surface of cornstalks with biocarbon based template. The as-formed biocarbon based composite materials (MoS2/C) were used in lithium-ion battery and supercapacitors. It showed outstanding electrochemical properties as anode materials in LIBs, the discharge capacity was 1129 mAh g−1 (or 339 mAh g−1) after 100 cycles at a current density of 0.1 A g−1 (or 1 A g−1). Furthermore, the composites possessed a high specific capacitance of 338.3 F g−1 and good cycling stability as negative electrode in supercapacitors. BET and XPS results confirmed the large specific surface areas and heterogeneous structures of the composite materials, which endowed them more active sites and excellent conductance properties conducive to improve the energy storage properties. So, biocarbon based template method and this composite material had great application prospects in the field of energy.

With the rise in biometric-based identity authentication, facial recognition software has already stimulated interesting research. However, facial recognition has also been subjected to criticism due to security concerns. The main attack methods include photo, video, and three-dimensional model attacks. In this paper, we propose a multifeature fusion scheme that combines dynamic and static joint analysis to detect fake face attacks. Since the texture differences between the real and the fake faces can be easily detected, LBP (local binary patter) texture operators and optical flow algorithms are often merged. Basic LBP methods are also modified by considering the nearest neighbour binary computing method instead of the fixed centre pixel method; the traditional optical flow algorithm is also modified by applying the multifusion feature superposition method, which reduces the noise of the image. In the pyramid model, image processing is performed in each layer by using block calculations that form multiple block images. The features of the image are obtained via two fused algorithms (MOLF), which are then trained and tested separately by an SVM classifier. Experimental results show that this method can improve detection accuracy while also reducing computational complexity. In this paper, we use the CASIA, PRINT-ATTACK, and REPLAY-ATTACK database to compare the various LBP algorithms that incorporate optical flow and fusion algorithms.

Aryl hydrocarbon-receptor nuclear translocator (ARNT2) is a member of the bHLH PAS (basic helix-loop-helix Period/ARNT/Single-minded) family of transcription factors. Recently, some studies indicate that ARNT2 is associated with the occurrence and development of carcinoma. However, its roles in gastric cancer (GC) remain unclear. In the present study, we found that ARNT2 expression level is lower in GC tissues compared with adjacent non-tumor tissues, and negatively correlated with depth of invasion of the tumor, differentiated degree, and poor survival of GC patients. Overexpression of ARNT2 inhibits cell proliferation. Furthermore, AKT pathway contributed to ARNT2 -mediated PC proliferation. Taken together, our results provide the first evidence that high expression of ARNT2 inhibited proliferation of GC cells and affected tumor aggressiveness in GC patients.

In recent years, face recognition has rapidly developed in the field of smartphones and control systems. It has been used to unlock the telephone and face-payment applications. With such rapid development, more and more demands are placed on the security of face recognition. However, face biometric-based recognition technologies are still vulnerable to spoofing attacks. Thus, developing robust and reliable antispoofing attack detection is critical to guarantee the security of facial analysis-based authentication. As deep learning techniques have achieved satisfactory performances in computer vision, they can also be employed to face spoofing detection. We present a multichannel linear local binary pattern optimization algorithm, which combines with Lucas–Kanade optical flow algorithm. The extracted facial features are fused and sent to a deep belief network classifier for classification and learning, and finally tested on the MSU-mobile facial spoofing database. Compared with existing deep leaning-based detection methods, our face spoofing detection algorithm has better scalability and robustness. To evaluate the performance of the proposed algorithm, the experiments are conducted on three crossed standard spoofing databases and excellent performance is also achieved.

Previous mining excavation in upper sublevels left several mined-out areas in Haigou gold mine. To ensure safety of the main and auxiliary shafts and mining production in deeper sublevels, systematical studies on regularity, prediction, and control of ground pressure in the mine were carried out. Through 3D-numerical modeling and in-situ monitoring of acoustic emission, pressure and displacement, the ground pressure activity and the stability status of surrounding rock masses and the two shafts were assessed. Based on in-situ monitoring practice in Haigou mine, 4 modes to judge rock stability according to the monitoring information of acoustic emission, pressure, and displacement were presented.

Blast design is a critical factor dominating fragmentation and cost of actual bench blasts. However, due to the varying nature of rock properties and geology as well as free surface conditions, reliable theoretic formulae are still unavailable at present and in most cases blast design is carried out by personal experience. As an effort to find a more scientific and reliable tool for blast design, a computer-aided bench blast design and simulation system, the BLAST-CODE model, is developed for Shuichang surface mine, Mining Industry Company of the Capital Iron and Steel Corporation Beijing. The BLAST-CODE model consists of a database representing geological and topographical conditions of the mine and the modules Frag + and Disp + for blast design and prediction of resultant fragmentation and displacement of rock mass. The two modules are established in accordance with cratering theory qualitatively and modified quantitatively by regression of the data collected from 85 bench blasting practices conducted i...