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In order to solve the problem of difficult extraction of low permeability high gas coal seams, based on the existing research results, a coal seam gas-liquid composite fracturing pressure relief and permeability enhancement technology was proposed through theoretical analysis. The technology mainly relies on the high-pressure acid and high-pressure alkali liquid injected into the borehole to crack the coal seam, while the high-pressure CO2 gas generated by the liquid reaction plays a role in displacing and increasing the permeability; the technology has the dual effect of pressure relief and permeability increase, and cuts off the preparation stage of outburst; the ground stress field and gas pressure field are reduced and homogenized after the coal seam fracturing and permeability increase, and the extraction efficiency is improved. The outstanding features of the technology are: the reaction products are neutral and easy to dissolve, a small amount of acidification and permeability increasing products support the effect and weaken the fracture closure; the reaction temperature rises to avoid excessive CO2 adsorption and permeability reduction; the technology combination is flexible and changeable.

Wearable sensors designed for continuous, non‐invasive monitoring of physicochemical signals are important for portable healthcare. Oxide field‐effect transistor (FET)‐type biosensors provide high sensitivity and scalability. However, they face challenges in mechanical flexibility, multiplexed sensing of different modules, and the absence of integrated on‐site signal processing and wireless transmission functionalities for wearable sensing. In this work, a fully integrated wearable oxide FET‐based biosensor array is developed to facilitate the multiplexed and simultaneous measurement of ion concentrations (H+, Na+, K+) and temperature. The FET‐sensor array is achieved by utilizing a solution‐processed ultrathin (≈6 nm thick) In2O3 active channel layer, exhibiting high compatibility with standard semiconductor technology, good mechanical flexibility, high uniformity, and low operational voltage of 0.005 V. This work provides an effective method to enable oxide FET‐based biosensors for the fusion of multiplexed physicochemical information and wearable health monitoring applications. [ABSTRACT FROM AUTHOR]

Advanced photonic integrated circuits require large-scale integration of high-speed electro-optic (EO) functional components on a chip. Low power consumption and high operation speed are thus key metrics for almost all integrated EO devices. Here, we demonstrated a ring resonator modulator based on lead zirconate titanate (PZT) on a SiO2/Si substrate. The ridge waveguides were employed to keep a large spatial overlap between the optical field and the electric field within the PZT layer. The device exhibits a data rate of 56 Gbit/s and significant tuning efficiency, reaching up to 35.8 pm/V, corresponding to 1.17 V·cm. The demonstration of energy efficient and high-speed EO modulation paves the way for realizing dense PZT photonics integrated circuits. [ABSTRACT FROM AUTHOR]

High quality single-crystal fcc-Co(x)(Mg(y)Zn(1-y))(1-x)O(1-v) epitaxial thin films with high Co concentration up to x = 0.5 have been fabricated by molecular beam epitaxy. Systematic magnetic property characterization and soft X-ray absorption spectroscopy analysis indicate that the coexistence of ferromagnetic regions, superparamagnetic clusters, and non-magnetic boundaries in the as-prepared Co(x)(Mg(y)Zn(1-y))(1-x)O(1-v) films is a consequence of the intrinsic inhomogeneous distribution of oxygen vacancies. Furthermore, the relative strength of multiple phases could be modulated by controlling the oxygen partial pressure during sample preparation. Armed with both controllable magnetic properties and tunable band-gap, Co(x)(Mg(y)Zn(1-y))(1-x)O(1-v) films may have promising applications in future spintronics.

Bio‐inspired neuromorphic vision sensors, integrating optical sensing, and processing functions have attracted significant attention for developing future low‐power and high‐efficiency imaging systems. However, the compulsory electrical signal modulation to achieve inhibitory behaviors in most reported neuromorphic vision sensors results in additional hardware and computational latency. Herein, bidirectional photoresponsive optoelectronic synapses based on In2O3/Al2O3/Y6 phototransistors are achieved, realizing all‐optical‐configured synaptic weight updates enabled by dual photogates. The inhibitory and excitatory photoresponses originate from the photogating effects provided by trapped photogenerated electrons in Al2O3 under near‐infrared light and the ionized oxygen vacancies in In2O3 under ultra‐violet light, respectively. The bidirectional phototransistor illustrates outstanding optoelectronic synaptic characteristics with low nonlinearity and asymmetry, demonstrating high efficiencies in both preprocessing and postprocessing tasks, such as noise reduction, contrast enhancement, and pattern recognition. The proposed dual‐photogate optoelectronic synapses provide effective strategies to construct high‐efficiency neuromorphic vision sensors and in‐sensor computing systems. [ABSTRACT FROM AUTHOR]

In order to verify the influence law of water content in coal to gas adsorption and desorption characteristics, gas adsorption and desorption experiments were carried out in different equilibrium pressure conditions with different water content in coal. The experiment results show that the gas adsorption capacity decreases with increasing of water content in coal, it could be corrected by use of water content influence coefficient in practical application. With the water content increasing, the gas desorption became slower and the amount of gas remaining was greater. The water filled in the coal gap has inhibitory effect to gas adsorption and desorption.

Polymer electrolyte membrane fuel cells are considered one of the alternatives to fossil energy sources. The slow kinetics of the oxygen reduction reaction (ORR) at the cathode and the high price of Pt-based catalysts remain one of the key challenges for the commercial viability of proton exchange membrane fuel cells. However, their high cost and susceptibility to poisoning severely limit their use for large-scale commercial applications in fuel cells. Heteroatom-doped porous carbon has attracted extensive attention from scientists due to its advantages such as high specific surface area and the properties conferred by heteroatom doping. On the one hand, we discuss a variety of current methods for the preparation of heteroatom-doped porous carbons, including the template method and the activation method. On the other hand, we discuss the application of heteroatom-doped porous carbon in Pt catalysts, transition metal catalysts and metal-free catalysts. Finally, we also present the pre-existing and challenges of heteroatoms in ORR catalysis, which will drive the development of ORR catalysts. [ABSTRACT FROM AUTHOR]