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The global energy shortage has become more and more serious, which promotes the urgent need to shift to sustainable development. The value-added 5-hydroxymethylfurfural (HMF) can be derived from biomass wastes and can be used to synthesize various valuable chemicals, recently gaining researchers’ attention. Reaction from glucose or fructose to HMF is the most common method for HMF production and has been widely studied in the presence of various catalysts. Among these catalysts, heterogeneous catalysts, such as metal-supported catalysts, have been extensively developed due to its easy recovery and little secondary pollution formation. This review provides a systematic critical overview of recent researches on conventional metal-supported catalysts for the conversion of glucose and fructose to HMF. We compared the catalytic characteristics of metals in the preparation of HMF under various supporting materials and indicated their reaction mechanism. This review aims to provide references for further in-depth development of green and efficient catalysts and to make recommendations for future industrial applications of such catalysts.

Sulfonamides as the major antibiotic have become emerging contaminants worldwide in aquatic environments. Herein, a heterogeneous Fenton-like oxidation driven by a novel BF-PMCs bismuth ferrites reported firstly for efficient degradation of sulfamethoxazole (SMX) in which the possible degradation pathways are thoroughly analyzed through identifying some of key intermediates (i.e., C8H11N3O4S, C4H4NO2, etc.) using liquid chromatography-mass spectrum (LC-MS), monitoring organic acids (i.e., acetic acid, pyruvic acid) and inorganic anions (i.e., sulfate, nitrate) using ion chromatography (IC), and detecting radical species (i.e., HO ) using both chemical quenchers and fluorescence technique, simultaneously. The optimal operations in BF-PMCs/H2O2 system for SMX degradation are recommended at the conditions of initial pH ~4.5, 1.5 mg L−1 [SMX], 70 mM [H2O2], and BF-PMCs loading of 0.2 g L−1. The degradation rates (kinetic value of kapp) for SMX, azoxystrobin, bisphenol A, and 2,4-dichlorophenol are 9.5 × 10−3, 13.6 × 10−3, 7.3 × 10−3, and 5.9 × 10−3 min−1, respectively. Meanwhile, the degradation rates in BF-PMCs/H2O2 system for SMX degradation are slightly slower in the presence of inorganic anions (e.g., Cl−, NO3−) and NOM (e.g., humic acid). Based on an overall consideration, the BF-PMCs/H2O2 system has great potential for degradation of emerging organic pollutants (EOPs) in natural water systems.

Synthesis of precursor Ni0.8Co0.1Mn0.1(OH)2 in regular sphere shape as nickel-rich cathode material for Li-ion batteries remains challenging. Here, we report that the morphology of Ni0.8Co0.1Mn0.1(OH)2 can be tuned by controlling the reaction conditions of co-precipitation. The effects of the concentration of NH3·H2O, pH of reaction solution, and stirring speed were studied in detailed. Precursor Ni0.8Co0.1Mn0.1(OH)2 with outstanding spherical hierarchical structure was successfully prepared. The cathode material of LiNi0.8Co0.1Mn0.1O2 was then synthesized based on the prepared Ni0.8Co0.1Mn0.1(OH)2. It showed excellent crystal structure, morphology and electrochemical properties. Within the voltage range of 2.7–4.3V, the initial discharge specific capacity was 203.7mAh·g-1 and 198.8mAh·g-1 at rate of 0.1C and 0.2C (1C = 200 mA g-1, at 30°C), and the capacity retention were 94.4% and 88.0% for 100cycles and 200cycles (0.2C, at 30°C), respectively.

In spaceborne gravitational-wave detectors, the stringent requirements on the magnetic cleanliness of the test masses (TMs) make the development of ground-based characterization techniques of their magnetic properties important. An electrostatically controlled torsion pendulum has been built to measure the magnetic properties of TianQin-like solid TMs. The remanent magnetization ${m}_{r}$ and the magnetic susceptibility $\ensuremath{\chi}$ of TMs can be measured at the level of 1 nA ${\mathrm{m}}^{2}$ and $8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$, respectively. The precisions of measurements are mainly limited by the mechanical sensitivity of silicon fiber. The experimental results from a solid tungsten TM as an example show that the apparatus provides a feasible way to investigate the bulk effect of a full-size TM for the TianQin mission with enough resolution.

With the presence of emerging organic pollutants (EOPs) in aqueous systems, the heavy metals (HMs)-transfer mechanism has been given considerable attention again. Here, a facile molten-salt method is used to successfully convert banana waste into nanoflake-assembled biochar (BC350) for the first time. It is a type of macro-mesoporous biochar with a pore size composed of ~ 3.8 nm and ~ 50 nm, and its maximum adsorption capacities are 459 mg g−1 for Pb2+ and 148 mg g−1 for tetracycline (TC), which outperforms the reported adsorbents ranging from several times to dozens of times. The pore-filling effect, electrostatic interaction, coordination affinities and π-π stacking as synergistically physical/chemical adsorption behaviors of BC350 on Pb2+/TC that has been comprehensively elucidated relying on adsorption kinetics and isotherms, and key effect parameter investigation. The competitive adsorption effect becomes insignificantly in the adsorption efficiency of BC350 on Pb2+/TC cross contamination at a control condition. Moreover, BC350 also exhibits outstanding adsorption efficiency (>95%) on Pb2+/TC in five industrial wastewater samples. This study contributes to a plausible mechanism in biochar adsorption removal of metal/organics cross contamination and its potential application explored in industrial wastewater treatment.

High energy density lithium-ion batteries are eagerly required to electric vehicles more competitive. In a variety of circumstances closely associated with the energy density of the battery, positive electrode material is known as a crucial one to be tackled. Among all kinds of materials for lithium-ion batteries, nickel-rich layered oxides have the merit of high specific capacity compared to LiCoO2, LiMn2O4 and LiFePO4. They have already become one of the most attractive candidates for the mainstream batteries in industries. In this work, the recent advances on three commonly concerned nickel-rich layered oxides are presented. The preparation, microstructure, electrochemical performances are focused, the modification including coating design as well as dopant selection is specially discussed in details, which is essential to enhance the durability and energy density of lithium-ion batteries. Additionally, the prospects and challenges are also systematically discussed, as well as the potential applications in the field of energy storage technologies.

Nickel-rich LiNi0.8Co0.1Mn0.1O2 is a promising and attractive positive electrode material for application in lithium-ion battery for electric vehicles, due to its high specific capacity, low cost and lower toxicity. However, poor calendar storage performance, high initial capacity loss, low cycle life, and poor thermal stability have seriously hindered its commercialization. In this work we focus on the recent progress on the synthesis and modification of layered LiNi0.8Co0.1Mn0.1O2 positive electrode material. Developments in synthesis, effect of doping and coating, and the concentration gradient LiNi0.8Co0.1Mn0.1O2 are presented.

Aim Dilated cardiomyopathy (DCM) is characterised by left ventricular dilation and associated with systolic dysfunction. Recent evidence has reported the high expression of latent transforming growth factor beta binding protein 2 (LTBP2) in heart diseases, which may play a role in regulating multiple biological functions of myocardial cells. Thus, this study set out to investigate the molecular mechanism and effects of LTBP2 in myocardial oxidative stress injury, fibrosis and remodelling in a rat model of DCM, with the involvement of NF-κB signalling pathway. Methods The rat model of DCM was treated with si-LTBP2 and/or activator of NF-κB signalling pathway to examine the haemodynamic indexes, cardiac functions, oxidative stress injury, fibrosis and remodelling. Moreover, in vitro experiments were conducted to verify the regulatory role of LTBP2 and NF-κB signalling pathway in DCM. Results LTBP2 was up-regulated in DCM rats. After LTBP2 was knocked down, haemodynamic indexes, HW/BW ratio, collagen volume fraction (CVF) level, positive expression of LTBP2, levels of reactive oxygen species (ROS), malondialdehyde (MDA), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), tumour necrosis factor beta 1 (TGF-β1) and brain natriuretic peptide (BNP) were all decreased. Meanwhile, levels of LTBP2, Col-I, Col-III, p65 and p52 were also reduced, while HW, BW and levels of SOD and TAOC were increased. In contrast, activation of NF-κB signalling pathway reversed effects of LTBP2 gene silencing. These findings were confirmed by in vivo experiments. Conclusions LTBP2 silencing can attenuate myocardial oxidative stress injury, myocardial fibrosis and myocardial remodelling in DCM rats by down-regulating the NF-κB signalling pathway.

A simple approach to the highly fluorescent near-infrared aza-BODIPY dyes with higher fluorescence quantum yields (up to 0.81 in toluene) in comparison with their known analogues is presented. Our approach is based on the restricted rotations of the 1,7-phenyl groups to the mean plane of the aza-BODIPYs, which is achieved through the installation of bulky substituents on the 1,7-phenyl groups of aza-BODIPYs and results in a reduced nonradiative relaxation process in solution. The large torsion angles between the 1,7-phenyl groups and the aza-BODIPY core (ϕ1 and ϕ2 in these novel conformationally restricted aza-BODIPYs) were confirmed by X-ray diffraction studies.

Recombinant Escherichia coli cells expressing d -hydantoinase were used as the biocatalysts for the production of N-carbamoyl- d -hydroxyphenylglycine from dl -p-hydroxyphenylhydantoin. Although high concentrations of DMSO could lead to enzyme denaturation, in the presence of 1.5% DMSO, the rate of product formation increased by more than 80% due to enhanced permeability of the cell membrane and increased substrate concentration. Reduced mass transfer resistance, achieved by the permeabilization of cell membrane with CTAB and glutaraldehyde, led to a 60% increase in the rate of production. However, in addition to causing a shift of optimal pH toward lower pH, permeabilization of the cell membrane resulted in reduced enzyme stability toward thermal and organic denaturation. Nevertheless, the stability of the d -hydantoinase of the recombinant cells toward pH, temperature and organic solvents can be significantly enhanced by immobilization.

Recombinant Escherichia coli BL21 (DE3) harbouring plasmid pET36 encoding d -hydantoinase from Pseudomonas putida were used as biocatalyst for the production of N -carbamoyl- d -hydroxyphenylglycine from dl - p -hydroxyphenylhydantoin. The optimum d -hydantoinase activity was observed at 40°C and pH 8.5. At a substrate concentration of 300 mg/l, an initial reaction rate of 24.52 mM/h g cells was obtained and 91% of the substrate was converted into product after a 24-h reaction. Recombinant cells were immobilized within calcium alginate beads with diameters ranging from 2 to 3 mm. The specific activity of the immobilized cells increased with cell loads, probably due to reduced mass transfer resistance. The immobilized cells also exhibited an optimal pH of 8.5. However, under the conditions described above, the initial reaction rate with the immobilized cells as the biocatalysts was reduced by 87% to 3.19 mM/h g cells, probably due to the formation of cell aggregates inaccessible to substrate. Thermostability and reusability of d -hydantoinase were increased upon immobilization. The initial reaction rate with immobilized cells was increased with temperature at least up to 60°C. More than 95% of the d -hydantoinase activity was recovered after three cycles for the immobilized cells, compared to 22% for the free cell systems.