Abstract: Wave-absorbing materials in the form of a nickel-carbon composite that includes a plurality of modified carbon particles, where each of the modified carbon particles includes a nickel nanoparticle core and a carbon layer wrapped on a surface of the nickel nanoparticle core; and a plurality of the modified carbon particles form an octahedral structure. When a high-frequency microwave interacts with the nickel-carbon composite, the composite has a stronger magnetic loss performance due to various magnetic loss characteristics such as natural resonance and eddy current loss of the magnetic nickel nanoparticles. In addition, the carbon layer, as a shell layer, can provide a directional electron migration path in a special octahedral space structure to construct a conductive network.

Abstract: Disclosed is an underwater robot for a mine flooding rescue, including a starting unit configured to control the implementation of a whole rescue action; a drive unit connected with the starting unit and configured to provide a robot with power to move; and an execution unit connected with the drive unit and configured to salvage underwater life sources.

Abstract: Disclosed is a synchronous detection system for a trace nitrogen-oxygen compound based on photoacoustic spectrometry, including a NOx (Nitrogen Oxide) detection air channel, a dust detection air channel and a double-photoacoustic spectrometry detection mechanism which are mutually connected in parallel; the NOx detection air channel includes a background interference detection air pipe, a NO2 detection air pipe and a NO detection air pipe that are mutually connected in parallel, and a NOx photoacoustic detection cavity; and the dust detection air channel includes a dust detection air pipe and a dust photoacoustic detection cavity communicating with the dust detection air pipe.

Abstract: The present application relates to an attitude self-correcting underground transportation apparatus based on UWB technology and a control method thereof. A transport clamping and fastening mechanism is mounted on an upper platform part of a six-degree-of-freedom motion platform. An attitude perception and sensing set at least includes three UWB tags being configured to acquire position information.

Abstract: Tandem methods and devices for separating coal and gangue based on visible light and an X-ray are provided. The method comprises: determining, based on a visible light image, an image feature set and a target region of coal gangue; recognizing the coal gangue and removing large gangue in the coal gangue; performing imaging on the coal gangue after the large gangue is removed; extracting a target image and determining a gray scale value of the target image; obtaining samples of coal and gangue of different granularity levels by performing sampling; establishing a database and obtaining a separation threshold of coal and gangue of each granularity level of the current mining area; forming a mapping set and storing the database in a storage space; and obtaining a gray scale value of subsequent coal gangue, importing the gray scale value of the subsequent coal gangue into the mapping set to subsequently separate coal and gangue.

Abstract: A system of monitoring vibration of a blasting model test for a jointed rock mass and a method are provided. The system includes: a loading subsystem for three-way load, a model-surface blasting-vibration acquisition subsystem, and a model-interior dynamic stress-strain acquisition subsystem. The system and the method are provided, and a blasting model for a transparent jointed rock mass and a monitoring method that are obtained can analyze the influence of a joint inclination angle on propagation and attenuation laws of blasting stress waves in the jointed rock mass, and can analyze the influence of different millisecond blasting modes on the stability of an existing tunnel in the jointed rock mass, and can capture a real-time dynamic evolution process of cracks. The stress and strain measurement technologies used can perform omnibearing monitoring and recording for large deformations of surrounding rock under blasting load, and can resist the electromagnetic interference.

Abstract: The present disclosure discloses a catalyst and a method for preparing 2-ethoxyphenol by catalytic depolymerization of lignin. The catalyst comprises sepiolite as a carrier and tungsten, nickel and molybdenum as active components supported on sepiolite. The catalyst for preparing 2-ethoxyphenol by catalytic depolymerization of lignin in the present disclosure can catalytically depolymerize lignin, realize the directional preparation of 2-ethoxyphenol from lignin, and co-produce lignin oil. It has a comparatively high selectivity for 2-ethoxyphenol and can achieve a lignin conversion rate of more than 95%, a 2-ethoxyphenol selectivity of more than 20% in a liquid product, and a yield of more than 100 mg/g of lignin.

Abstract: Disclosed is a synchronous detection system for a trace nitrogen-oxygen compound based on photoacoustic spectrometry, including a NOx (Nitrogen Oxide) detection air channel, a dust detection air channel and a double-photoacoustic spectrometry detection mechanism which are mutually connected in parallel; the NOx detection air channel includes a background interference detection air pipe, a NO2 detection air pipe and a NO detection air pipe that are mutually connected in parallel, and a NOx photoacoustic detection cavity; and the dust detection air channel includes a dust detection air pipe and a dust photoacoustic detection cavity communicating with the dust detection air pipe.

Abstract: Disclosed is an underwater robot for a mine flooding rescue, including a starting unit configured to control the implementation of a whole rescue action; a drive unit connected with the starting unit and configured to provide a robot with power to move; and an execution unit connected with the drive unit and configured to salvage underwater life sources.

Abstract: The present invention relates to the field of coal mine underground auxiliary transportation equipment, and particularly relates to an overhead monorail driving unit group realizing mechanical fast power distribution. The overhead monorail driving unit group realizing mechanical fast power distribution includes a rail, wherein the rail is connected with driving portions, carrying trolleys and a hoisting beam, the hoisting beam is disposed in a middle position of the driving portions and the carrying trolleys, and the driving portions, the carrying trolleys and the hoisting beam are connected through driving portion short pull rods, frame-shaped pull rods and driving portion long pull rods.

Abstract: The present invention discloses a multi-energy complementary system for a co-associated abandoned mine and a use method. The multi-energy complementary system for a co-associated abandoned mine includes a mining mechanism, a grouting mechanism and an energy mechanism. In the present invention, the mining of coal and uranium resources is realized through the mining mechanism, the subsidence and seepage reduction of the stratum is realized through the grouting mechanism, and the effective utilization of waste resources is realized through the energy mechanism. Finally, with the efficient cooperation of the three mechanisms, safe and efficient development and utilization of co-associated resources in the full life cycle are realized, and the purposes of green and efficient mining of coal and uranium resources and secondary development of a coal seam goaf are achieved, thereby facilitating the realization of dual-carbon goals and the development of low-carbon green energy.

Abstract: The present disclosure provides a test system and a method for measuring efficiency of underground coal gasification, and relates to the technical field of underground coal gasification, comprising a gasification agent supply system, a gasifier, an outlet and recycling system and a monitoring system, wherein the gasification agent is mainly injected into the gasifier and then chemically reacts with the coal by igniting the gasifier at a high temperature to generate gas, while after the gas passes through the outlet and recycling system, the composition and content are measured, and the monitoring system monitors an operating state of the gasifier, injection of the gasification agent and production of gas, temperature change in the gasification channel and ignition temperature and pressure gauge data.

Abstract: Disclosed is a method for measuring gas pressure of a close-distance seam group simultaneously, including the following steps: constructing a pressure-measuring drill hole inclined downwards; lowering a first seam piezometer tube, lowering a baffle and a polyurethane blocking material after a tube head reaching a lowermost seam; and installing a gas pressure gauge; lowering a second seam piezometer tube, lowering the baffle and the polyurethane blocking material after the tube head reaching a second layer of seam; and installing the gas pressure gauge; lowering a nth seam piezometer tube, lowering the baffle and the polyurethane blocking material after the tube head reaching a nth layer of seam; and installing the gas pressure gauge; injecting a high-water and quick-solidifying material into the drill hole; and connecting the gas pressure gauges through optical fibers, and connecting the gas pressure gauges with a ground control system.

Abstract: An intelligent experimental device for collaborative mining of associated resources includes a signal transmission mechanism, a pressure maintaining mechanism, a feeding mechanism, and a reaction mechanism. The signal transmission mechanism includes a centralized controller, an annunciator, signal receivers, a power supply, a power cord, signal transmitters, and signal sensing valves. The pressure maintaining mechanism includes ambient and axial pressure oil chambers, ambient and axial pressure pumps, ambient and axial pressure liquid distribution tanks, a comprehensive pressure distribution pipe, and hydraulic transmission pipes. The feeding mechanism includes monitoring analyzers, temperature controllers, solution transfer pipes, seepage pumps, mixture conveying pipes, a comprehensive liquid distributor, an aggregate chamber, a liquid chamber, an oil chamber, a gas chamber, a mixing chamber and an analytical purifier.

Abstract: A system for detecting a concentration of free SiO2 in coal dust includes a first sampling tube and a second sampling tube for sampling the coal dust, a three-way control valve communicated with the first sampling tube and the second sampling tube respectively, a photoacoustic spectrometry detection device communicated with the three-way control valve through a connecting pipeline, and a SiO2 reaction tube for reacting SiO2 in the coal dust; and the SiO2 reaction tube is disposed on the second sampling tube. In the present disclosure, a coal dust sampling line is convenient to change by disposing the three-way control valve, and the first sampling tube and the second sampling tube are respectively communicated with the photoacoustic spectrometry detection device, so as to perform a differential accurate detection of the reacted CO content, and to obtain the SiO2 content.

Abstract: Disclosed is a method for measuring gas pressure of a close-distance seam group simultaneously, including the following steps: constructing a pressure-measuring drill hole inclined downwards; lowering a first seam piezometer tube, lowering a baffle and a polyurethane blocking material after a tube head reaching a lowermost seam; and installing a gas pressure gauge; lowering a second seam piezometer tube, lowering the baffle and the polyurethane blocking material after the tube head reaching a second layer of seam; and installing the gas pressure gauge; lowering a nth seam piezometer tube, lowering the baffle and the polyurethane blocking material after the tube head reaching a nth layer of seam; and installing the gas pressure gauge; injecting a high-water and quick-solidifying material into the drill hole; and connecting the gas pressure gauges through optical fibers, and connecting the gas pressure gauges with a ground control system.

Abstract: A gas-liquid spray dust settlement system for a fully mechanized mining face includes an atomization humidification subsystem, a boundary mist curtain subsystem, and a dust mist recycling subsystem that are all arranged outside the fully mechanized mining face, where the boundary mist curtain subsystem includes high-pressure blade nozzles mounted to hydraulic supports. The atomization humidification subsystem includes a spray dust settler mounted to a rocker arm of a coal cutter and configured to spray water mist completely covering the high-pressure blade nozzle. The dust mist recycling subsystem includes a wind-water linkage dust remover mounted to a semi-encircling support base, arranged under the spray dust settler, and configured to collect the water mist sprayed by the spray dust settler.

Abstract: Methods for modifying a recycled fine powder of concrete and uses thereof. A method for modifying a recycled fine powder can include: crushing a collected waste concrete block with a crusher, grinding with a ball mill, and passing through a 100-mesh sieve, to obtain a recycled fine powder with d50 of 13.5 ?m; placing the obtained recycled fine powder in a dry environment at a high temperature, drying, then taking out, and cooling to room temperature; preparing tannic acid solutions with different concentrations, mixing the cooled recycled fine powder with the prepared tannic acid solutions, and continuously stirring by a glass rod.

Abstract: A system for detecting a concentration of free SiO2 in coal dust includes a first sampling tube and a second sampling tube for sampling the coal dust, a three-way control valve communicated with the first sampling tube and the second sampling tube respectively, a photoacoustic spectrometry detection device communicated with the three-way control valve through a connecting pipeline, and a SiO2 reaction tube for reacting SiO2 in the coal dust; and the SiO2 reaction tube is disposed on the second sampling tube. In the present disclosure, a coal dust sampling line is convenient to change by disposing the three-way control valve, and the first sampling tube and the second sampling tube are respectively communicated with the photoacoustic spectrometry detection device, so as to perform a differential accurate detection of the reacted CO content, and to obtain the SiO2 content.

Abstract: The present disclosure relates to a method and system for determining a rational width of a gob-side working face under a condition of thick and hard key strata. The method includes: constructing a piecewise function with a width of a gob-side working face as an independent variable; obtaining values of parameters of the gob-side working face; determining a solution set based on the values of the parameters of the gob-side working face, the piecewise function, and a predetermined function threshold; and determining a numerical value according to the solution set as a rational width and mining the gob-side working face according to the rational width.