Abstract: The invention provides a method for preparing pyrrolidone, and the invention provides a method for catalytically preparing pyrrolidone with ?-aminobutyric acid in the presence of carnitine-CoA ligase CaiC. The carnitine-CoA ligase CaiC has an amino acid sequence as shown in SEQ ID NO:1. The ligase has catalytic activity in the cyclization of ?-aminobutyric acid to produce pyrrolidone. The carnitine-CoA ligase provided in the present invention affords a yield of pyrrolidone of 3.26 g/L and a molar yield of 39.53% in 24 h when ?-aminobutyric acid is used as a substrate, thus reducing the production period, improving the production of pyrrolidone, and accelerating the industrialization process of producing pyrrolidone by enzymatic conversion method.

Abstract: A method for enhancing compressive strength of a lead smelting water-quenched slag-based cementitious material by mechanical activation is provided, belonging to the technical field of solid waste resource treatment. The method includes following steps: grinding and activating water-quenched slag from lead smelting, then mixing with calcium-based solid waste, magnesium-based solid waste, magnesium oxide, portland cement and water, and performing a steam curing and a curing at normal temperature on cementitious material slurry obtained to obtain the lead smelting water-quenched slag-based cementitious material.

Abstract: An apparatus for sensing motion of a subject's head comprises three conductive threads, each of which has a resistance that varies in response to strain thereof, circuitry for applying a voltage across the threads, circuitry for detecting current flowing through the threads, a data-collection system configured to detect the current, and a data-processing system that classifies, based on data provided by the data-collection system, a type of motion of the head and an extent of the motion.

Abstract: A disk lock management method, apparatus, and system are disclosed. The method is performed by a first node, including: sending an obtaining request to a data storage system, where the obtaining request is used to request to obtain a disk lock; receiving a release request, where the release request is used to request the first node to release the disk lock; and sending, a release message to the data storage system, where the release message is used to release the disk lock. This method avoids frequent application and releasing operations performed on the disk lock, reduces disk IO resource occupancy caused by application and releasing of the disk lock, and improves overall system performance.

Abstract: A disk lock management method, apparatus, and system are disclosed. The method is performed by a first node, including: sending an obtaining request to a data storage system, where the obtaining request is used to request to obtain a disk lock; receiving a release request, where the release request is used to request the first node to release the disk lock; and sending, a release message to the data storage system, where the release message is used to release the disk lock. This method avoids frequent application and releasing operations performed on the disk lock, reduces disk TO resource occupancy caused by application and releasing of the disk lock, and improves overall system performance.