Abstract: A composite solution for enhancing induced disease resistance of lentinan (LNT) to a plant, a preparation method of the composite solution, and a method for enhancing induced disease resistance of LNT to a plant are provided. The composite solution for enhancing induced disease resistance of LNT to a plant includes: an LNT-containing solution and an SPc-containing solution, where SPc is a dendritic macromolecule functionalized by an amino functional group, and has a structural formula shown in formula I, where n=1 to 100. An LNT/SPc complex is produced in the composite solution. SPc spontaneously combines with LNT through hydrogen bonding, such that an agglomerate structure formed by LNT in an aqueous solution is broken and reduced to a nano-scale particle size, and a spherical particle is produced, which can significantly reduce a contact angle of the LNT aqueous solution, and promote the distribution and diffusion of LNT.

Abstract: A closed variable-frequency heat pump drying device with a heat regenerator includes a variable-frequency compressor, a condenser, a throttling valve, an evaporator, a heat regenerator, a three-way valve, a variable-frequency fan, an air inlet temperature sensor, an air inlet humidity sensor, a drying bin, an air outlet temperature sensor, an air outlet humidity sensor and a controller. The controller regulates frequency of the variable-frequency compressor by comparing magnitudes of actual and set air inlet temperatures; a ratio of a straight-through air volume to a regenerated air volume of the three-way valve by comparing magnitudes of actual and set air inlet humidity; and frequency of the variable-frequency fan by comparing magnitudes of actual and set air humidity difference and magnitudes of actual and set air temperature difference of medium air entering and exiting the drying bin.

Abstract: A method for detecting abnormal direct current voltage measurement in a modular multilevel converter high voltage direct current transmission system is provided. In the method, a valve group voltage at a detection pole is obtained, voltages at voltage measurement points at the detection pole are collected, and comparison and determination are performed based on the actual arrangement of the voltage measurement points, and then whether an abnormal measurement occurs at each of the voltage measurement points is determined.

Abstract: Provided is a steam turbine overspeed protection system, includes a drive gear arranged to match a rotation speed of a rotor of a steam turbine; a rotating shaft parallel to an axis of the drive gear and capable of rotating at a critical rotation speed; a protective gear arranged on the rotating shaft and forming a lead screw nut mechanism with the rotating shaft, and arranged to be capable of engaging with the drive gear when the rotation speed of the drive gear exceeds the critical rotation speed; and an operating rod connected to the protective gear; wherein, when the drive gear engages with the protective gear, the protective gear can move in the axial direction of the rotating shaft and thereby drive the operating rod to move and produce an action that activates a protection device for preventing steam turbine overspeed.

Abstract: Provided is a steam turbine overspeed protection system, includes a drive gear arranged to match a rotation speed of a rotor of a steam turbine; a rotating shaft parallel to an axis of the drive gear and capable of rotating at a critical rotation speed; a protective gear arranged on the rotating shaft and forming a lead screw nut mechanism with the rotating shaft, and arranged to be capable of engaging with the drive gear when the rotation speed of the drive gear exceeds the critical rotation speed; and an operating rod connected to the protective gear; wherein, when the drive gear engages with the protective gear, the protective gear can move in the axial direction of the rotating shaft and thereby drive the operating rod to move and produce an action that activates a protection device for preventing steam turbine overspeed.