Abstract: Disclosed are a mine dust real-time detection system based on double-photoacoustic spectrometry and a detection method. The mine dust real-time detection system based on double-photoacoustic spectrometry includes a first sampling unit, a first photoacoustic detection cavity, a second sampling unit, a second photoacoustic detection cavity, a signal unit and a processing unit; the first sampling unit is used for sampling in respective, the first photoacoustic detection cavity provides a photoacoustic effect field to substances sampled by the first sampling unit, the second sampling unit is used for sampling in respective, the second photoacoustic detection cavity provides the photoacoustic effect field to substances sampled by the second sampling unit, the signal unit is used for providing a laser signal, and the processing unit is used for collecting and processing a photoacoustic signal.

Abstract: A high sensitivity flexible three-dimensional force tactile sensor includes a hemispherical contact, wherein the hemispherical contact includes a tray with a groove on the surface and a hemispherical protrusion arranged in the groove. A flexible inverted cone component connected to the lower surface of the hemispherical contact, wherein a plurality of flexible triangular excitation electrode is arranged on the side surface of the flexible inverted cone component. A flexible common electrode surrounding part of the flexible triangular excitation electrode, wherein a first cavity with an opening is opened inside the flexible common electrode, parts of the flexible triangular excitation electrode and the flexible inverted cone component are arranged in the first cavity of the flexible common electrode. The flexible triangular excitation electrode and the flexible inverted cone component have no contact with the inner wall of the first cavity of the flexible common electrode to form an air cavity.

Abstract: The present invention proposes a coal and gangue separation device, including a first supporting seat, a guide part and multiple material bins. The guide part is hinged with the first supporting seat; the guide part rotates in a vertical direction; and inlets of the plurality of material bins are sequentially distributed on a rotation track of a movable end of the guide part. In the coal and gangue separation device of the present invention, the high-pressure airflow of a high-pressure nozzle does not directly act on the materials, but on grate bar driving mechanisms; and cantilever grate bars are driven to rotate by the grate bar driving mechanisms so as to directionally discharge the mineral aggregate. Therefore, the gangue can accurately enter a gangue collection bin; and the clean coal can accurately enter a clean coal collection bin.

Abstract: Disclosed is a rake-free thickening device including driving area. The device includes a feed assembly, a diversion assembly and a clean coal collection assembly. The clean coal collection assembly includes a driving area. The diversion assembly includes a central tank. Slime water passes through the feed assembly and flows with a medicament from an upper part of the central tank to a middle of the central tank, and then diffuses around. Bubbles carry the fine slime up after reacting. The driving zone drives the dispersed bubbles to a defoaming zone located in the middle of the central tank. The slime water in the central tank flows through the central tank after defoaming. With the continuously filling of slime water, the slime water above the central tank overflows the central tank to the clean coal collection assembly within the diversion and settlement area.

Abstract: A pitch control method and system of a symmetrical-airfoil vertical axis wind turbine collects data by an anemometer, an anemoscope and an angle sensor, outputs an optimum pitch angle based on a control law of a pitch angle and controls the pitch angle to be the optimum pitch angle through a pitch control actuator. In addition to input variables of the control law such as a wind velocity vin and a blade azimuth angle ?, constants such as a rotation radius R, a rotation velocity ? of the blade and aerodynamic coefficients c1, c2 and c3 are also related. A Reynolds number has little influence on three aerodynamic coefficients c1, c2 and c3. The pitch actuator controls the adjustment rods to realize the automatic pitch control of the blades. An expression of the control law of the pitch is concise, the calculation time is short, and a response speed is fast.

Abstract: The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

Abstract: A flocculating, grading, and dewatering device includes a tank body, a mixing zone, a flocculent settling zone, a centrifugal dewatering zone, and a particle screening zone. An initial material is mixed with a chemical agent for a flocculation reaction, a lower sediment material settles and an upper liquid overflows. In the centrifugal dewatering zone, a screen basket is allowed to rotate to facilitate a centrifugal movement of the sediment material, water in the sediment material moves into a guide cavity and then flows to a centrifugate outlet, and then a dewatered material in the screen basket is removed out of the screen basket. In the particle screening zone, a screening mechanism screens particles of different size grades in the dewatered material, and water generated flows downward and is discharged; liquids discharged from the centrifugate outlet and the overflow port are combined, and then discharged through a mixed liquid outlet.

Abstract: A dosimetry assessment method for an organ at risk (OAR) in an esophageal radiotherapy plan includes: acquiring volumetric-modulated arc therapy (VMAT) plan data of a patient with esophageal cancer, and obtaining a distance-target histogram (DTH); subjecting a geometric feature vector of the DTH to dimension reduction to obtain a dimension-reduced geometric feature vector; establishing a deep belief network (DBN) model, and completing training the DBN model; non-linearly fitting a correlation between a dose feature vector and the dimension-reduced geometric feature vector to obtain a dose feature vector with a dimension being identical to a dimension of the dimension-reduced geometric feature vector; and reconstructing the dose feature vector through a decoding layer of an autoencoder structure to obtain a dose feature vector with a dimension being identical to a dimension of the geometric feature vector before the dimension reduction, and finally obtaining a dose-volume histogram (DVH) for predicting the OAR

Abstract: A sprayer for settling dust of a coal mine includes: an outer housing, having at least one opening configured to spray water mist; a sprayer, placed in the outer housing, configured to spray water mist through the opening; a plurality of water curtain nozzles, configured to spray water curtain lines outside the opening to block suspended dust; and a support, configured to support the outer housing. The water curtain nozzles are in an equidistant arrangement around a center of the opening. A plurality of the water curtain nozzles are constructed such that the nozzles are all oriented toward the same point, to form a circular or conical water curtain.

Abstract: The present disclosure discloses a modular large spherical tank internal detection device with a self-locking function, and belongs to the technical field of safety detection of large spherical tanks. The detection device includes a transmission group and a detection group. A movable pin is matched with the rotation of a second motor in an unconnected state, so that inner central shafts rotate to realize up-down movement of a detecting instrument in a vertical plane. The movable pin is matched with the rotation of a first motor in a connected state, so that the whole detection device rotates round a central axis of a large spherical tank to realize horizontal circumferential movement of the detecting instrument. All detection of a spherical surface inside the large spherical tank can be completed by combining two types of movement of the detecting instrument.

Abstract: A device for measuring a flow velocity and a flow direction and geological parameters of groundwater through cross holes of deep wells includes detectors and a device for throwing the tracer source. A method includes measuring a correspondence between a conductivity and a concentration of a tracer solution at different temperatures in a laboratory; selecting at least two boreholes; selecting a target aquifer section; placing the detectors in the target aquifer section in the hole to test a conductivity background value and a temperature value; using the device for throwing the tracer source to place the tracer solution in the hole for throwing the tracer source, and using the detectors to measure a water conductivity and temperature in a detection hole, to obtain a distribution curve of a tracer solution solubility with time; performing cross-test, and calculating the seepage flow velocity and flow direction of groundwater in the hole.

Abstract: The present disclosure provides a phase sensitivity calibration method based on a phase generated carrier (PGC) technology, which is characterized in that in the operation process of a PGC algorithm, an additional calibration signal with a phase of known magnitude is applied through a phase modulator. This signal is demodulated through an arctangent algorithm or a differential cross multiplication algorithm, and a demodulated output value corresponding to a unit phase in the algorithm is obtained. The phase of known magnitude can be obtained by converting a carrier modulation depth parameter according to a certain ratio.

Abstract: The present invention relates to a photoelectric coal and gangue sorting device and a sorting method therefor. The device comprises a support frame, a coal and gangue separation screen body, a sealing upper cover, a sieving mechanism, a driving mechanism, a separating and conveying mechanism, a positioning plate and a sorting unit; the coal and gangue separation screen body, on the top of which is provided with the sealing upper cover and inside of which is provided with the separating and conveying mechanism, is fixedly installed on one side of the support frame by means of bolts; the side wall of the positioning plate, which is arranged above the separating and conveying mechanism, is fixed to the inner wall of the coal and gangue separation screen body by means of spot welding.

Abstract: The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

Abstract: The present disclosure provides a sense amplifier, a memory, and a method for controlling a sense amplifier, relating to the technical field of semiconductor memories. The sense amplifier comprises: an amplification module; and a control module, electrically connected to the amplification module; wherein, in an offset compensation stage of the sense amplifier, the control module is used to configure the amplification module to comprise a diode structure, a current mirror structure, and an inverter with an input and an output connected together; and in a first amplification stage of the sense amplifier, the control module is used to configure the amplification module as an inverter. The present disclosure can realize the offset compensation of the sense amplifier, thereby improving the performance of semiconductor memories.

Abstract: An improved 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: A passive energy-storage exoskeleton for assisting elbow joint is provided, which includes an upper arm unit, a lower arm unit, and an elbow joint unit located therebetween, the upper arm unit is rotatably connected with the lower arm unit. The elbow joint unit includes an anti-gravity mechanism, a coil spring mechanism, and a lower-arm-unit self-locking mechanism. The anti-gravity mechanism generates an equilibrant moment to eliminate the influence of the weight of the arm of the user and the weight of the device on the elbow joint. The lower-arm-unit self-locking mechanism is configured for locking/releasing the lower arm unit at any specified angle of rotation. The coil spring mechanism is configured for capturing and storing kinetic energy generated by rotation and swing of the arm of the user and releasing the energy as required.

Abstract: The present disclosure provides a sense amplifier, a memory, and a method for controlling a sense amplifier, relating to the technical field of semiconductor memories. The sense amplifier comprises: an amplification module, configured to read data in a storage unit on a bit line or a storage unit on a reference bit line; and a first switch module, configured to control the amplification module to be disconnected from the reference bit line when the sense amplifier reads a first state for the bit line and the sense amplifier is in an amplification stage, and control the amplification module to be connected to the reference bit line when the sense amplifier reads a second state for the bit line and the sense amplifier is in the amplification stage. The present disclosure can reduce the power consumption of the sense amplifier.

Abstract: A preparation method of a cube-like ZnSnO3 composite coated with highly graphitized fine ash comprises steps: S1: with the gasified fine slag of pulverized coal as a raw material, preparing the fine ash by adopting a three-step acidification method; and S2: adding the fine ash prepared in the Si into a container filled with distilled water, ultrasonically dispersing for 20-40 min, adding equal molar masses of SnCl4.5H2O and (Zn(NO3).6H2O respectively, uniformly stirring, dropwise adding ammonia into the mixed solution and magnetically stirring until the pH value of the mixed solution is 12, heating the mixed solution, washing the product obtained with deionized water and ethanol for 2-4 times, and finally drying to obtain a ZnSnO3@fine composite. With the dielectric property and conductivity adjusted, the composite prepared reveals a good impedance matching performance and an improved MA performance.

Abstract: A dosimetry assessment method for an organ at risk (OAR) in an esophageal radiotherapy plan includes: acquiring volumetric-modulated arc therapy (VMAT) plan data of a patient with esophageal cancer, and obtaining a distance-target histogram (DTH); subjecting a geometric feature vector of the DTH to dimension reduction to obtain a dimension-reduced geometric feature vector; establishing a deep belief network (DBN) model, and completing training the DBN model; non-linearly fitting a correlation between a dose feature vector and the dimension-reduced geometric feature vector to obtain a dose feature vector with a dimension being identical to a dimension of the dimension-reduced geometric feature vector; and reconstructing the dose feature vector through a decoding layer of an autoencoder structure to obtain a dose feature vector with a dimension being identical to a dimension of the geometric feature vector before the dimension reduction, and finally obtaining a dose-volume histogram (DVH) for predicting the OAR