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Hydrazine-assisted water electrolysis offers a feasible path for low-voltage green hydrogen production. Herein, the design and synthesis of ultrathin RhRu0.5 -alloy wavy nanowires as bifunctional electrocatalysts for both the anodic hydrazine oxidation reaction (HzOR) and the cathodic hydrogen evolution reaction (HER) is reported. It is shown that the RhRu0.5 -alloy wavy nanowires can achieve complete electrooxidation of hydrazine with a low overpotential and high mass activity, as well as improved performance for the HER. The resulting RhRu0.5 bifunctional electrocatalysts enable, high performance hydrazine-assisted water electrolysis delivering a current density of 100 mA cm-2 at an ultralow cell voltage of 54 mV and a high current density of 853 mA cm-2 at a cell voltage of 0.6 V. The RhRu0.5  electrocatalysts further demonstrate a stable operation at a high current density of 100 mA cm-2 for 80 hours of testing period with little irreversible degradation. The overall performance greatly exceeds that of the previously reported hydrazine-assisted water electrolyzers, offering a pathway for efficiently converting hazardous hydrazine into molecular hydrogen.

Using an industrial CT scanning system, we observed the characteristics of micro-fracture Generation and expansion in coal under different gas pressure conditions, providing a new basis for revealing the factors controlling the gas flow output of coal seams. The results of the test analysis showed that: under the action of non-adsorbed gas, the growth rate of fracture volume and fracture area percentage decreases gradually as the pore pressure increases and the sprouting and expansion of microfractures inside coal becomes more obvious. Fracture expansion equation under the influence of pore pressure is satisfied; microfracture extension is mainly controlled by stress concentration effect and coal matrix shrinkage effect. Under the action of adsorptive gas, with the extension of adsorption time, generation and expansion in coal of micro fissures become more and more significant until the expansion equilibrium; the growth rate of fissure volume and fissure area percentage then gradually becomes smaller, in line with the fissure expansion equation under the influence of adsorption time; the fracture extension is mainly affected by stress concentration effect, coal matrix shrinkage effect, erosion effect and deterioration mechanism. The larger the adsorption pressure the longer the adsorption equilibrium time required for the coal; the micro fissure expansion equilibrium time is longer than the gas adsorption equilibrium time, and the fissure expansion has obvious hysteresis.

Aiming at the problem that existing image text cross-modal retrieval is difficult to fully exploit the local consistency in the mode in the common subspace, a cross-modal retrieval method based on improved graph convolution is proposed. In order to improve the local consistency within each mode, the modal diagram is constructed with a single sample as a node, fully mining the interactive information between features. In order to solve the problem that graph convolution network can only do shallow learning, the method of adding initial residual link and weight identity map in each layer of graph convolution is adopted to alleviate this phenomenon. In order to jointly update the central node features through higher-order and lower-order neighbor information, an improvement is proposed to reduce neighbor nodes and increase the number of layers in graph convolution network. In order to learn highly locally consistent and semantically consistent public representation, it shares the weights of common representation learning layer, and jointly optimizes the semantic constraints within the modes and the modal invariant constraints between modes in the common subspace. The experimental results show that on the two cross-modal data sets of Wikipedia and Pascal sentence, the average mAP values of different retrieval tasks are 2.2%~42.1% and 3.0%~54.0% higher than the 11 existing methods. [ABSTRACT FROM AUTHOR]

In order to study the characteristic parameters of particulate coal gas desorption and diffusion within a negative pressure environment, a self-made particulate coal gas desorption experimental system was used to simulate the law of gas desorption and diffusion in the initial negative pressure stage of the negative pressure sampling process, and to study the particulate coal at different adsorption equilibrium pressures （0.5 MPa, 0.74 MPa and 1 MPa） and different negative pressures （-40 kPa, -50 kPa and -60 kPa） gas desorption and diffusion laws, and based on the classical diffusion model of the third kind of boundary conditions, the characteristic parameters of gas desorption and diffusion are analyzed. The research result shows that the ultimate gas desorption capacity of particulate coal increases with the increase of the negative pressure value of the environment, and the ultimate gas desorption capacity increases with the increase of the adsorption equilibrium pressure and rate of increase becomes smaller; under the same adsorption equilibrium pressure, with the increase of the negative pressure value, the mass transfer Biotherm and the mass transfer Fourier increase accordingly. The larger the negative pressure value, the smaller the external convective mass transfer resistance of particulate coal, the depth of the disturbance of the diffusion field goes deeper into the coal particles; the diffusion coefficient increases with the increase of the negative pressure value under the same adsorption equilibrium pressure, and decreases with the increase of the adsorption equilibrium pressure under the same negative pressure value, and the negative pressure value increases. The increase of negative pressure changes the kinetic parameters of gas desorption and accelerates the gas desorption and diffusion.

Background Lung cancer is the leading cause of cancer‐related death. Even if early detection and treatment have proven to be effective, the survival outcomes are still poor. Methods Tissue samples and clinicopathological data of 244 patients with clinical T1N0M0 NSCLC were collected. We investigated CXCR4, CXCR5 and CCR7 expression levels using the immunohistochemical method and analyzed their correlations with clinicopathological characteristics and survival outcomes. Results Elevated expression levels of CXCR4, CXCR5 and CCR7 were found in tumor tissues (P

An experimental apparatus was custom-designed to scrutinize the evolution of temperature and methane pressure during the freezing process in both soft and hard coal samples. Additionally, a thermal–hydrological–mechanical coupling theoretical model was developed, and temperature and methane pressure evolutions were simulated using COMSOL software. It was observed that methane pressure and temperature within the coal samples underwent two distinct phases during the freezing process: an initial rapid decline followed by a more gradual reduction. An exponential function was found to describe aptly the correlation of methane pressure or temperature in the coal samples with both freezing time and radial direction. Moreover, it was discerned that the thermal conductivity of soft coal is inferior to that of hard coal, and the radial decay coefficient of methane pressure or temperature in both types of coal is inversely proportional to freezing time. Significantly, it was revealed that, in post-freezing treatment, ethane pressure in both soft and hard coal could be reduced to 0.74 MPa. This finding elucidates the potential applicability of cryogenic methods for the theoretical elimination of coal seam outbursts. The results furnish a vital understanding of the physical properties of coal under cryogenic conditions, and they can inform the optimization of cryogenic treatment procedures for industrial applications. [ABSTRACT FROM AUTHOR]