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Chloride ion batteries, as attractive energy storage systems, possess the merits of abundant resources, reliable safety, and high theoretical volumetric energy density. Among the current cathode materials for chloride ion batteries, metal chlorides with high theoretical gravimetric energy density have been regarded as some of the most promising candidates as cathode materials. However, owing to the dissolution of metal chlorides into the liquid electrolyte, forming soluble complex anions (e.g. [CuCl4]2− and [NiCl4]2−) that subsequently shuttle to the anode, their cycling lifespans are typically limited to just one cycle. Herein, graphene oxides with different loading contents are coated onto a commercial glass fiber separator by vacuum filtration and sandwiched between a CuCl2 or NiCl2 cathode and the separator. The as-prepared graphene oxide coating layers with appropriate channel size allow the selective passage of Cl− while blocking the transportation of complex anions across the separator. Through the incorporation of the permselective GO coating layers, the electrochemical performance of the metal chloride cathodes is significantly enhanced. The maximum initial discharge capacities of 452 and 541 mA h g−1 at 10 mA g−1 can be achieved with the CuCl2 and NiCl2 cathodes, respectively. Reversible capacities of 144 mA h g−1 and 177 mA h g−1 are still retained after 30 cycles for the CuCl2 and NiCl2 cathodes, respectively. The corresponding energy densities of 1107 W h kg−1 for CuCl2 and 1022 W h kg−1 for NiCl2 are superior to those of previously reported cathodes. [ABSTRACT FROM AUTHOR]

Introduction and application prospect of new technologies were discussed such as centralized control and unattended intelligent control of conveyor belt, anti-tearing of conveyor belt, new technology of energy saving and reduction, rapid installation and withdrawal technology. The realization of unattended monitoring was described from three aspects of vision function, hearing function and touch function. A new longitudinal tearing recognition device for mine conveyor belt was introduced, it uses camera video recognition technology to identify and judge damage of conveyor belt real timely. It is analyzed that application of new rubber conveyor belt with aramid as the skeleton material, the intelligent technology of video recognition, and low-resistance stainless steel roller can effectively save energy and reduce consumption. A non-foundation fixing method for rapid installation and withdrawal of belt conveyor was introduced. The application of the new technologies of mine-used belt conveyor will gradually realize the functions of high intelligence centralized automatic control, quick and efficient installation and withdrawal of belt conveyor, and lay a solid foundation for safe, high yield and high efficiency of coal mine.

Principles and shortcomings of balance jack control of hydraulic support by use of compensation valve, high pressure internal overflow valve, floating two-way lock and automatic balance valve respectively were analyzed, and an optimal design scheme of the balance jack control loop of hydraulic support was proposed according to pressure characteristics of the balance jack cavity. Automatic fluid replacement and unloading of the balance jack cavity are realized by reasonably disposing components such as hydraulic pressure controlled reversing valve and low pressure unloading valve, so as to solve problem of safety valve frequently opening under non-emergency situation. The simulation and test results verify effectiveness of the optimal design scheme.

In this study, a surface-enhanced Raman spectroscopy (SERS) magnetic sensor is established based on SERS principle and magnetic separation technology, and a highly sensitive, simple and fast method for quantitative detection of neutralizing antibodies (nABs) and specific IgG of SARS-CoV-2 in plasma is established combined with immunoassay. Two kinds of Raman nanospheres (RNPs) with different characteristic Raman shifts are used as signal sources and coupled to ACE2 and anti-IgG (FC) antibodies respectively, and magnetic beads are coupled to RBD. The competitive relationship between ACE2 and nABs, the binding relationship between specific IgG and anti-IgG (FC) antibodies are determined. The results show that the concentrations of nABs and specific IgG in the range of 10–2000 ng ml−1 are well correlated with SERS response intensity, and the recoveries are both between 90%–110%, with good precision. Bilirubin and common anticoagulants have no interference on the detection results. This method is accurate, reliable, sensitive and does not require complex pre-treatment, and is expected to be used for simultaneous detection of nABs and specific IgG in plasma of SARS-CoV-2. It has guiding significance for the development and evaluation of vaccines and the formulation of individualized vaccination schedule. [ABSTRACT FROM AUTHOR]

In view of problems of poor support effect, slow support speed, high support cost and great labor intensity of advance support with advanced hydraulic support, single hydraulic prop or timber in return airway of fully-mechanized high cutting coal mining face of a coal mine in Yulin mining area, a high cutting chock type hydraulic support was designed. Finite element analysis of the support was conducted under three kinds of operating conditions namely top beam eccentric load and pedestal torsion, top beam torsion and pedestal concentrated load, top beam concentrated load and pedestal eccentric load. The stress nephogram and deformation nephogram show that the whole support is stressed uniformly without apparent stress concentration phenomenon and large deformation. The field test result show that the support can effectively guarantee safety of working face roadway with small deformation of surrounding rock of roadway.

In view of safety problems such as premature separation of roof, advance of cutting line and rib fall of coal wall caused by being lack of initial support force of hydraulic support, a manual pressurization device for initial support force of hydraulic support was designed. The pressurization device is in parallel with hydraulic check valve of original support lifting hydraulic system, improves the initial support force through manual operation of pressurization under the premise that normal lift is not affected. AMESim modeling and simulation of the pressurization control circuit before and after applying the manual pressurization device were carried out. The simulation results show that the manual pressurization effect of the device is obvious. The field test result of pressurized situation for initial support force of ZY8500/21/45D type support on a coal mine working face shows that the manual pressurization device can significantly improve initial support force of the support and meet the coal mining demand.

The imbalance between energy density and power density largely limits lithium-ion hybrid capacitor (Li-HEC) advance for various applications. In this work, we report on the construction of a binder-free and porous electrode, which is self-standing T-Nb2O5/graphene hybrid aerogels, as Li-intercalating pseudocapacitive electrodes of Li-HECs. The aerogels, with ultrafine T-Nb2O5 nanorods (10 ~ 40 nm) uniformly growing on the surface of graphene, feature short lithium-ion transport length, large specific surface area, 3D porous structure and good conductivity, and thus demonstrate both reversible specific capacity (~190 mAh/g at 1 C) and good rate capability (~90 mAh/g at 20 C). Most importantly, Li-HEC devices using activated graphene foam as binder-free cathode can achieve excellent energy densities (53 and 19.7 Wh/kg at power of 355 and 2009 W/kg, respectively) and remarkable cycling performance (capacitance retention of 89% after 3000 cycles), benefitting from good matching between cathode and anode as well as their fascinating microstructures. [ABSTRACT FROM AUTHOR]