Abstract: A laterally diffused metal oxide semiconductor device and a preparation method thereof are disclosed. The semiconductor device includes: a substrate; a body region having a first conductivity type and formed in the substrate; a drift region, having a second conductivity type, formed in the substrate and adjacent to the body region; a field plate structure, formed on the drift region, a lower surface of an end of the field plate structure close to the body region being flush with the upper surface of the substrate, and the end of the field plate structure close to the body region also having an upwardly extending inclined surface; and a drain region, having a second conductivity type, formed in an upper layer of the drift region, and in contact with the end of the field plate structure away from the body region.

Abstract: A sampling device and method for evaluating ecological risk of soil in a high geological background area comprises an impact sampling mechanism, a soil layer stripping mechanism and an auxiliary support frame. The impact sampling mechanism comprises a sampling hopper with a downward opening. A connecting sliding rod is fixedly arranged on the top of the sampling hopper. An upper end of the connecting sliding rod is connected with an impact rod. The impact rod is internally provided with an impact hammer capable of reciprocating along an axis of the impact rod. The soil layer stripping mechanism comprises a stripping sliding cylinder in sliding fit with the connecting sliding rod, and a support disc. A plurality of stripping plates are connected to a lower side edge of the support disc in a sliding fit mode.

Abstract: A sampling device and method for evaluating ecological risk of soil in a high geological background area comprises an impact sampling mechanism, a soil layer stripping mechanism and an auxiliary support frame. The impact sampling mechanism comprises a sampling hopper with a downward opening. A connecting sliding rod is fixedly arranged on the top of the sampling hopper. An upper end of the connecting sliding rod is connected with an impact rod. The impact rod is internally provided with an impact hammer capable of reciprocating along an axis of the impact rod. The soil layer stripping mechanism comprises a stripping sliding cylinder in sliding fit with the connecting sliding rod, and a support disc. A plurality of stripping plates are connected to a lower side edge of the support disc in a sliding fit mode.

Abstract: The invention provides a continuous preparation method of 2,3,3,3-tetrafluoropropene, comprising the following steps: carrying out liquid-phase catalytic telomerization reaction on ethylene and carbon tetrachloride serving as initial raw materials in the presence of a composite catalyst to obtain a reaction product; performing two-stage membrane separation and purification on the reaction product, and then sequentially performing a primary high-temperature cracking reaction, a gas-phase chlorination reaction, a secondary high-temperature cracking reaction, a primary gas-phase catalytic fluorination reaction and a secondary gas-phase catalytic fluorination reaction to obtain a reaction product; condensing and rectifying the secondary gas-phase catalytic fluorination reaction product to obtain the 2,3,3,3-tetrafluoropropene product.

Abstract: An automatic cleaning device, comprising: a moving platform configured to automatically move on an operation surface; a cleaning module which is provided on the moving platform and comprises a wet-type cleaning module configured to clean at least a part of the operation surface in a wet-type cleaning mode and a dry-type cleaning module configured to clean at least a part of the operation surface in a dry-type cleaning mode; and a floating lifting/lowering structure connected to the dry-type cleaning module and configured to enable the dry-type cleaning module to passively move up and down relative to the moving platform.

Abstract: A self-inspection method for a hydraulic control turning system of a generator rotor includes: establishing a length dimension relationship table among a plurality of hydraulic cylinders of the hydraulic control turning system; selecting a reference hydraulic cylinder, and acquiring a reference length dimension when the reference hydraulic cylinder is located at a target working position, the target working position is a position at which a turning pin corresponding to the reference hydraulic cylinder is inserted into an adapted hole; and performing a function inspection of a motion execution module in sequence by the plurality of the hydraulic cylinders, based on the reference length dimension and the length dimension relationship table.

Abstract: A high temperature resistant polyimide film and its preparation method. The present invention relates to a polyimide film and its preparation method and solves the problems of honeycomb's and skin panel's core adhesive-polyimide film with insufficient heat resistance, no climbing of bonding core structure and adhesive fillet formation. The high temperature resistant polyimide film is made by polyimide solution, inorganic filler modifier and interface coupling agent by the steps of: under specific temperature and stirring conditions, adding inorganic filler modifier and interface coupling agent to polyimide solution, stirring to obtain the adhesive agent; filtering and degassing the adhesive agent, casting to a stainless steel drum with carrier cloth and release paper to obtain a self-supporting film; then heating and annealing to obtain the final polyimide film. The present invention is applied to high temperature resistant polyimide film and its preparation method.

Abstract: A liquid crystal composition, a liquid crystal display element and a liquid crystal display including the liquid crystal composition, belonging to the field of liquid crystal display. The liquid crystal composition includes a compound represented by formula I and one or more compounds represented by formula II. The liquid crystal composition can increase the dielectric anisotropy and improve the voltage retention rate.

Abstract: A data transmission method includes detecting a delay between a source end and a sink end; determining a to-be-used second path when a first path currently used to transmit a packet is determined to be a congested path; determining a delay difference between the first path and the second path based on a delay of the first path and a delay of the second path; and sending one or more to-be-sent packets to the sink end through the second path based on the delay difference.

Abstract: A system for controlling a generator rotor locking pin, comprising a fixed locking pin and a rotor formed with a locking hole, and further comprising a detection reference component synchronously rotating with the rotor and formed with a detection hole, the detection hole radially corresponding to the locking hole; an optical quantity detection component fixed with respect to the rotor; and a control component configured to output a first control instruction to a rotor driving component according to a position signal of the detection hole obtained by the optical quantity detection component. The detection hole is used as an object to be detected, so that the circumferential relative position relationship of the locking hole with respect to the locking pin can be accurately determined, to output the first control instruction to the rotor driving component, thereby accurately centering the locking pin and the locking hole along with the rotation of the rotor.

Abstract: The invention provides a continuous preparation method of 2,3,3,3-tetrafluoropropene, comprising the following steps: carrying out liquid-phase catalytic telomerization reaction on ethylene and carbon tetrachloride serving as initial raw materials in the presence of a composite catalyst to obtain a reaction product; performing two-stage membrane separation and purification on the reaction product, and then sequentially performing a primary high-temperature cracking reaction, a gas-phase chlorination reaction, a secondary high-temperature cracking reaction, a primary gas-phase catalytic fluorination reaction and a secondary gas-phase catalytic fluorination reaction to obtain a reaction product; condensing and rectifying the secondary gas-phase catalytic fluorination reaction product to obtain the 2,3,3,3-tetrafluoropropene product.

Abstract: A rotor rotation control system for a wind turbine and a control method thereof are provided. The control system includes a rotation unit configured to drive a rotor of the wind turbine to rotate relative to an engine base of the wind turbine, a driving unit configured to drive the rotation unit, and a processor configured to determine a bending moment load switching position on a rotating shaft of the rotor, and output an adjustment instruction to the driving unit based on the bending moment load switching position.

Abstract: The invention relates to a liquid crystal composition, a liquid crystal display element and a liquid crystal display comprising the liquid crystal composition, belonging to the field of liquid crystal display. The liquid crystal composition of the present disclosure comprises a compound represented by formula I and one or more compounds represented by formula II. The liquid crystal composition can increase the dielectric anisotropy and improve the voltage retention rate.

Abstract: The invention relates to a liquid crystal composition, a liquid crystal display element and a liquid crystal display comprising the liquid crystal composition, belonging to the field of liquid crystal display. The liquid crystal composition of the present disclosure comprises a compound of formula I and one or more compounds of formula II. The liquid crystal composition can increase the dielectric anisotropy and improve the voltage retention rate.

Abstract: A control method for a hydraulic control turning system of a generator rotor includes: establishing a length relationship table between multiple hydraulic cylinders of the hydraulic control turning system; selecting a reference hydraulic cylinder; acquiring current lengths of the multiple hydraulic cylinders when the multiple hydraulic cylinders are located at error correction positions; and adjusting lengths of the other hydraulic cylinders corresponding to a next driving stroke to conform with the length relationship table. With such an arrangement, the accumulated dimension error between the hydraulic cylinders may be dynamically corrected during the turning operation, thereby ensuring that the turning pins are accurately aligned with the pin holes in the generator, and the corresponding turning operation is performed after the generator set is locked. Based on this, a control device for a hydraulic control turning system of a generator rotor is further provided.

Abstract: A high temperature resistant polyimide film and its preparation method. The present invention relates to a polyimide film and its preparation method and solves the problems of honeycomb's and skin panel's core adhesive—polyimide film with insufficient heat resistance, no climbing of bonding core structure and adhesive fillet formation. The high temperature resistant polyimide film is made by polyimide solution, inorganic filler modifier and interface coupling agent by the steps of: under specific temperature and stirring conditions, adding inorganic filler modifier and interface coupling agent to polyimide solution, stirring to obtain the adhesive agent; filtering and degassing the adhesive agent, casting to a stainless steel drum with carrier cloth and release paper to obtain a self-supporting film; then heating and annealing to obtain the final polyimide film. The present invention is applied to high temperature resistant polyimide film and its preparation method.

Abstract: A high temperature resistant polyimide film and its preparation method. The present invention relates to a polyimide film and its preparation method and solves the problems of honeycomb's and skin panel's core adhesive—polyimide film with insufficient heat resistance, no climbing of bonding core structure and adhesive fillet formation. The high temperature resistant polyimide film is made by polyimide solution, inorganic filler modifier and interface coupling agent by the steps of: under specific temperature and stirring conditions, adding inorganic filler modifier and interface coupling agent to polyimide solution, stirring to obtain the adhesive agent; filtering and degassing the adhesive agent, casting to a stainless steel drum with carrier cloth and release paper to obtain a self-supporting film; then heating and annealing to obtain the final polyimide film. The present invention is applied to high temperature resistant polyimide film and its preparation method.

Abstract: A rotor rotation control system for a wind turbine and a control method thereof are provided. The control system includes a rotation unit configured to drive a rotor of the wind turbine to rotate relative to an engine base of the wind turbine, a driving unit configured to drive the rotation unit, and a processor configured to determine a bending moment load switching position on a rotating shaft of the rotor, and output an adjustment instruction to the driving unit based on the bending moment load switching position.

Abstract: A control method for a hydraulic control turning system of a generator rotor includes: establishing a length relationship table between multiple hydraulic cylinders of the hydraulic control turning system; selecting a reference hydraulic cylinder; acquiring current lengths of the multiple hydraulic cylinders when the multiple hydraulic cylinders are located at error correction positions; and adjusting lengths of the other hydraulic cylinders corresponding to a next driving stroke to conform with the length relationship table. With such an arrangement, the accumulated dimension error between the hydraulic cylinders may be dynamically corrected during the turning operation, thereby ensuring that the turning pins are accurately aligned with the pin holes in the generator, and the corresponding turning operation is performed after the generator set is locked. Based on this, a control device for a hydraulic control turning system of a generator rotor is further provided.