Abstract: Provided are a precursor compound of a tetracyclic hydrocarbon and a preparation method thereof, and a tetracyclic hydrocarbon and a preparation method and use thereof. The precursor compound of the tetracyclic hydrocarbon with a structure shown in formula I has a polycyclic structure. The precursor compound is subjected to hydrodeoxygenation so as to be prepared into the tetracyclic hydrocarbon with a structure shown in formula II that has a high density (0.986 g/cm3), a high calorific value (41.14 MJ/L), and a low freezing point (less than ?60° C.).

Abstract: A method for improving smooth running of casting of rare earth stainless steel using pulse current includes the following steps: setting corresponding initial pulse voltage, pulse current, and pulse frequency in accordance with difference of rare earth element content in molten steel; and adjusting the pulse voltage, pulse current, and pulse frequency according to position change of stopper rod until the end of continuous casting. The method can stably improve the clogging of immersion nozzle during continuous casting, the smooth running of continuous casting and production efficiency, and decrease production cost.

Abstract: Provided are a precursor compound of a tetracyclic hydrocarbon and a preparation method thereof, and a tetracyclic hydrocarbon and a preparation method and use thereof. The precursor compound of the tetracyclic hydrocarbon with a structure shown in formula I has a polycyclic structure. The precursor compound is subjected to hydrodeoxygenation so as to be prepared into the tetracyclic hydrocarbon with a structure shown in formula II that has a high density (0.986 g/cm3), a high calorific value (41.14 MJ/L), and a low freezing point (less than ?60° C.).

Abstract: The present invention relates to the phosphatidylserine (PS) binding compound derivative and the fusion of PS binding compound with an arm compound. The present invention describes the methods of producing and using PS binding compound derivative and the fusion of PS binding compound with an arm compound by providing the functional group to couple with functional group containing fluorophore for multicolor flow cytometry and multiplex imaging; to conjugate with magnetic particle for depleting the PS positive cells; to couple with oligo comprising PCR handle sequence, and unique DNA barcode for PS positive cells and capture sequence for discriminating positive cells from live cells in Single-cell RNA sequencing.

Abstract: A device and method for preparing a low-impurity regenerated brass alloy through step-by-step insertion of an electrode are provided. The device includes a melt heating apparatus, an electrode displacement apparatus, and a pulse current generation apparatus. The automatic electrode lifting apparatus is controlled to adjust an insertion depth of the graphite electrode plate in the metal melt, and the pulse current generation apparatus is controlled to adjust the parameters of pulse current to achieve the impurity reduction on the metal melt. The preparation of a low-impurity regenerated brass alloy involves a short production process, simple operations, low energy consumption, and high impurity removal efficiency, and is suitable for regeneration and large-scale continuous production of non-ferrous metal alloys.

Abstract: A device and method for preparing a low-impurity regenerated brass alloy through step-by-step insertion of an electrode are provided. The device includes a melt heating apparatus, an electrode displacement apparatus, and a pulse current generation apparatus. The automatic electrode lifting apparatus is controlled to adjust an insertion depth of the graphite electrode plate in the metal melt, and the pulse current generation apparatus is controlled to adjust the parameters of pulse current to achieve the impurity reduction on the metal melt. The preparation of a low-impurity regenerated brass alloy involves a short production process, simple operations, low energy consumption, and high impurity removal efficiency, and is suitable for regeneration and large-scale continuous production of non-ferrous metal alloys.

Abstract: A vacuum solid solution method for nickel-free high manganese and nitrogen is provided and relates to the technical field of metal material heat treatment. By vacuumizing, heat homogenizing, keeping the temperature in the final temperature range, deoxidation, and rapid cooling treatment, the present method forms a single austenitic structure from the raw materials, and promotes full and uniform dispersion of nitrogen carbide, providing a nickel-free high nitrogen stainless steel with more stable comprehensive performance and wider range of application.

Abstract: A vacuum solid solution method for nickel-free high manganese and nitrogen is provided and relates to the technical field of metal material heat treatment. By vacuumizing, heat homogenizing, keeping the temperature in the final temperature range, deoxidation, and rapid cooling treatment, the present method forms a single austenitic structure from the raw materials, and promotes full and uniform dispersion of nitrogen carbide, providing a nickel-free high nitrogen stainless steel with more stable comprehensive performance and wider range of application.

Abstract: A method for recognizing a transformer partial discharge pattern based on a singular value decomposition (SVD) algorithm includes a training model and a classification recognizing process, comprising: firstly setting up an experimental environment having artificial defects, collecting at least one datum sample, and calculating statistical feature parameters of each datum sample to form a datum sample matrix; performing singular value decomposition on the datum sample matrix and determining an order of an optimal retention matrix by judging whether a feature of a retention matrix is clear, so as to obtain a type feature description matrix and a class-center description vector group after dimensionality reduction; preprocessing samples to be recognized to obtain a sample vector, and performing linear transformation on the sample vector utilizing a type space description matrix.