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A good bifunctional electrocatalyst can effectively drive water splitting to produce hydrogen gas. In this paper, NiMoO4an nanomaterial was prepared and combined with black phosphorus (BP) in a one-step method. Used as a bifunctional electrocatalyst, the composite demonstrated outstanding electrochemical performance with 162.7 mV and 137.6 mV achieving current densities of 20 mA cm−2 and 10 mA cm−2 for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), respectively. For overall water splitting, the potential was just 1.55 V to achieve 10 mA cm−2, and, especially, the value only rises by0.05 V after 2000 cycles of CV. Here, the one-step synthesis method favors the dispersion of NiMoO4 nanomaterial on the BP surfaces, and facilitates a combination between the nickel molybdate and the BP. Also, the excellent performance of the samples should benefit from the synergistic action between the components. [ABSTRACT FROM AUTHOR]

Based on the excellent piezoelectric properties of 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 (PMN–PT) single crystals, a hole-doped manganite film/PMN–PT heterostructure has been constructed to achieve electric-field and light co-control of physical properties. Here, we report the resistivity switching behavior of Eu0.7Sr0.3MnO3/PMN–PT(111) multiferroic heterostructures under different in-plane reading currents, temperatures, light stimuli and electric fields, and discuss the underlying coupling mechanisms of resistivity change. The transition from the electric-field induced lattice strain effect to polarization current effect can be controlled effectively by decreasing the in-plane reading current at room temperature. With the decrease of temperature, the interfacial charge effect dominates over the lattice strain effect due to the reduced charge carrier density. In addition, light stimulus can lead to the delocalization of eg carriers, and thus enhance the lattice strain effect and suppress the interfacial charge effect. This work helps to understand essential physics of magnetoelectric coupling and also provides a potential method to realize energy-efficient multi-field control of manganite thin films. [ABSTRACT FROM AUTHOR]

Background: Hsian‐tsao gum (HG) has unique gel‐promoting and nutritional properties; however, its use in processed foods is limited to starchy foods, partially due to a lack of knowledge related to its interaction with proteins. This study elucidated the interaction mechanism of heat‐induced gelatin (G) (50 g kg−1) gel fortified with HG (0 ~ 20 g kg−1) using rheology, Fourier‐transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), large deformation tests, low‐field nuclear magnetic resonance (LF‐NMR), and confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM). Results: Heating promoted synergistic interactions between G and more HG molecules with enhanced apparent viscosity and higher storage modulus G′ than loss modulus G″, thus shortening the gel time (tg) of G‐HG sols into gels. Fourier‐transform infrared spectroscopy and DSC also confirmed the chemical interactions that occurred, facilitating the formation of β‐sheet structures of G. The microstructure of G gradually formed separate, coarse strands, and aggregated as HG was added, as observed by CLSM and SEM. This accelerated the gel formation rate and changed the textural properties. Although HG caused a disruptive decrease in the helix structure of G, it was possible to compensate for this by accelerating synergistic interactions, including depletion attractions and Maillard reactions, by heating. Conclusion: Hsian‐tsao gum interacted synergistically with G as a result of heating and this accelerated the gel formation rate and improved the gel properties. Novel complex gels could be designed by blending HG to improve the gel properties of G in the heat processing of the food gel formulation. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Anti-oxidation coatings of MoSi2-SiC-Si-ZrB2 were prepared on the graphite surface by laser cladding. The XRD, scratching bonding force, SEM and isothermal oxidation tests were used to investigate the microstructure and properties of the coatings. The coating with 40 wt% ZrB2 added (MoSi2:SiC:Si:ZrB2 = 16:4:5:16.6) has the lowest degree of oxidation, the best oxidation resistance and the highest bonding strength between coating and matrix. The scratching bonding force still maintained at about 9.9 N after laser ablation, and there were no obvious destructive defects but some pores and cracks on the coating. After a Si-enriched amorphous layer was formed, the relative oxygen permeability was significantly decreased and the oxidation of the coating was passivated, which prevented the matrix from further oxidation. [ABSTRACT FROM AUTHOR]

In this paper, α-Fe2O3 was prepared by hydrothermal and chemical precipitation methods, respectively, and its gas sensing properties toward CH4 were systematically studied. The larger specific surface area of the materials provided them potential and considerable gas adsorption abilities. The results of gas-sensing measurements indicated the synthesized α-Fe2O3 materials presented a p-type conductive nature. The sensitivities of the devices based on the different material fabrication methods were measured to be 195% and 214%, respectively, at 370°C for the concentration of 2000 ppm CH4. In addition, the sensing mechanism was discussed and simulated by first-principles calculation. The results revealed the higher surface adsorption energy of α-Fe2O3, which verified the experimental conclusions of our work. Our research suggests that α-Fe2O3 is a promising candidate for CH4 gas sensing in many fields such as mining safety and environmental monitoring. [ABSTRACT FROM AUTHOR]

Scanning and transmission electron microscopy were used to characterize the morphology of the carbon microcoils (CMCs). The Raman spectra showed that CMCs had local regular structure as ID/IG = 0.841. Then, aligned CMCs/silicone-rubber composites (5 x 5 x 1 mm³) were fabricated by coating of silicone rubber on the CMCs. Their alternating current impedance characteristics were measured as a function of applied load and the pressure sensitivity was discussed. The results showed that the impedance decreased as the increasing applied load, and the sample with less CMCs owned high pressure sensitivity, which indicated a novel composite ?lm could act as an alternative of tactile sensor. [ABSTRACT FROM AUTHOR]

In the last decade, with the combined application of high efficiency preparation techniques, high resolution HPLC MS/MS and sophisticated NMR technologies, novel bitter derivatives of α-, iso-α-, β-acids have been identified in beer and model solutions, which has updated our knowledge of hop chemistry. In this review, newly identified cyclic and oxidative products of α-, iso-α-, β-acids in hops and beer, have been comprehensively described to give brewers a more in depth understanding of hop and beer bitterness chemistry. A total of 39 unique substances: 15 derived from α-acids, 15 from iso-α-acids, and 9 derived from β-acids are elucidated, including their structures, suggested formation mechanism, distribution profiles in model solutions or beer, reactions during fermentation, thresholds of some of these compounds, and their evolution during storage. [ABSTRACT FROM AUTHOR]

Four different mediums have been developed for the synthesis of PbSe nanostructures, with different size and morphology. The particles were obtained in solid state medium with size of only 60 nm on average which are much smaller than those gained in liquid and molten state mediums. The growth mechanisms of these PbSe nanostructures were discussed. Results show that the state of medium have a direct impact on the size of PbSe nanostructures and the alkalinity of environment plays a key part in the formation of PbSe nanocubes. On the other hand, the electrochemical property of two typical nanostructures was studied. In the CV curves, there are four reaction peaks corresponding to oxidation of the PbSe and Pb(OH), and the reduction of PbO and Pb(OH). Otherwise, nanorods with size of only 60 nm have greater structural stability than nanocubes. [ABSTRACT FROM AUTHOR]

A series of polymeric thin films with BFDT (BFDT = 4,5-bis(foroylsulfanyl)-1,3-dithiole-2-thione) doped in PMMA (polymethylmethacrylate) were fabricated by means of spin-coating on quartz substrate. The third-order nonlinear optical properties of the films were investigated by Z-scan technique at 532 nm wavelength with 20 ps pulse width. The influences of doping concentration for third-order nonlinearity were also studied. A self-defocusing effect was observed from the Z-scan curves and the nonlinear refractive index of the film increases with the increase in doping concentration. Our results suggest that considerable nonlinear optical properties were found in BFDT. In addition, it was found that the nonlinear coefficient of the BFDT-doped PMMA thin film was about two orders of magnitude larger than that of homologous materials with organic solvents. By analysis, we can conclude that the material is a potential candidate for applications of nonlinear optics and can be considered in the fabrication of all-optical switching devices, etc. [ABSTRACT FROM AUTHOR]

Given different crystallization habit of CoC 2 O 4 ·2H 2 O and NiC 2 O 4 ·2H 2 O, Co 1-x Ni x C 2 O 4 ·2H 2 O solid solutions with hierarchical structures have been rationally designed and fabricated via a chemical co-precipitation process. Typically, Co 0.5 Ni 0.5 C 2 O 4 ·2H 2 O presents hierarchical flower-like morphology due to the rivaling competing crystallization of orthorhombic and monoclinic phase. The sample possesses high specific surface area (124.8 m2/g) and delivers a superior specific capacitance of 1226 F g-1 at the current density of 1cA g−1. Moreover, Co 0.5 Ni 0.5 C 2 O 4 ·2H 2 O exhibits excellent rate capability (82.9% retention at 20 A g−1) and remarkable cycling stability (84.6% retention after 3000 cycles). The outstanding pseudocapacitive performance can be related to its orthorhombic-monoclinic hierarchical nanostructure, which not only improve ion and electron transfer but also facilitate surface redox reaction. Our work demonstrates Co 0.5 Ni 0.5 C 2 O 4 ·2H 2 O can be a promising candidate in energy storage for supercapacitors. Image 1 • Orthorhombic-monoclinic Co 1-x Ni x C 2 O 4 ·2H 2 O solid solutions were fabricated by a co-precipitation process. • Co 0.5 Ni 0.5 C 2 O 4 ·2H 2 O presents hierarchical nanostructure with high specific area. • Co 0.5 Ni 0.5 C 2 O 4 ·2H 2 O possesses superior specific capacitance, excellent rate capability and good cycle stability. [ABSTRACT FROM AUTHOR]

Based on the excellent piezoelectric properties of 0.7Pb(Mg 1/3 Nb 2/3 )O 3 -0.3PbTiO 3 (PMN-PT) single crystals, a hole-doped manganite film/PMN-PT heterostructure has been constructed to achieve electric-field and light co-control of physical properties. Here, we report the resistivity switching behavior of Eu 0.7 Sr 0.3 MnO 3 /PMN-PT(111) multiferroic heterostructures under different in-plane reading currents, temperatures, light stimuli and electric fields, and discuss the underlying coupling mechanisms of resistivity change. The transition from the electric-field induced lattice strain effect to polarization current effect can be controlled effectively by decreasing the in-plane reading current at room temperature. With the decrease of temperature, the interfacial charge effect dominates over the lattice strain effect due to the reduced charge carrier density. In addition, light stimulus can lead to the delocalization of e g carriers, and thus enhance the lattice strain effect and suppress the interfacial charge effect. This work helps to understand essential physics of magnetoelectric coupling and also provides a potential method to realize energy-efficient multi-field control of manganite thin films.

The increasing burden and health risks of antimicrobial resistance (AMR) pose a great threat to society overall. Lipopeptides exhibit great potential as novel and safe alternatives to traditional antibiotics. In this study, the strain YA215, which was isolated from the mangrove area in Beibu Gulf, Guangxi, China, was identified as Bacillus velezensis. Then, YA215 lipopeptide extracts (YA215LE) from B. velezensis was found to exhibit a wide spectrum of antibacterial and antifungal activities. Additionally, YA215LE was identified and found to contain three groups of lipopeptides (surfactin, iturin, and fengycin). Furthermore, one separation fraction (BVYA1) with significant antibacterial activity was obtained. Additionally, liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis of BVYA1 showed three molecular ion peaks ([M + H] + : m/z 980.62; 994.66; 1008.66) corresponding to conventional surfactin homologs. By MS/MS analysis, BVYA1 was identified as sufactin with the precise amino acid sequence Glu-Leu/Ile-Leu-Val-Asp-Leu-Leu/Ile and hydroxyl fatty acids with 11-13 carbons. [M + H] + at m/z 980.62 was detected for the first time in B. velezensis, which demonstrates that the strain corresponds to a new surfactin variant. In particular, BVYA1 showed antibacterial activity with the minimum inhibitory concentration (MIC) values of 7.5-15 μg/ml. Finally, the preliminary mechanism of inhibiting E. coli treated with BVYA1 showed that BVYA1 effectively permeabilized the cytoplasmic membrane and disrupted the morphology of targeted bacterial cells. In conclusion, this study suggests that the YA215LE from B. velezensis YA215 might be a potential candidate for a bactericide., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yu, Shen, Qin, Pang, Fan, Peng, Pei and Liu.)