Abstract: A purification method for detection of a strontium isotope in a silk cultural relic. The method includes: (1) enrichment of the strontium isotope: after cleaning the silk cultural relic, adding the silk cultural relic to a digestion agent for microwave digestion, and conducting evaporation drying; and adding a dried product to a nitric acid solution for centrifugal separation, and extracting a supernatant; and (2) purification of the strontium isotope: first, mixing 4?,4?(5?)-di-tert-butyldicyclohexano-18-crown-6 and a defoamer and adsorbed to a purified resin separation column, and pre-cleaning the purified resin separation column with a nitric acid solution; next, injecting the supernatant in step (1) into the purified resin separation column with a nitric acid solution as a carrier solution; and then, injecting an 84Sr solution and an elution solution into the purified resin separation column in sequence to obtain a separated and purified strontium solution.

Abstract: Disclosed is a particle algorithm-based method for underwater detection and operation positioning of a reservoir dam system. A water body is stimulated by adopting a smoothed particle hydrodynamics (SPH) method, the ROV is simulated by adopting a discrete element method (DEM) unit formed by a series of particles, an umbilical cable between the ROV and a water surface control unit are simulated by a spring unit, dynamic interaction among the ROV, water flow and the cable are calculated by combining the SPH method and the DEM, and real-time motion positions of the ROV and the cable in complex environments are calculated and obtained; and a relative position between the ROV and the surface control unit can be calculated through the real-time position of the cable, and the real-time underwater positioning of the ROV is realized in combination with an absolute coordinate position of the surface control unit.

Abstract: The technical field of physical fitness facilities relates to a skating machine includes a rack, supporting shafts, and a synchronizing assembly. The two supporting shafts are hinged to the rack side by side, pedals are hinged to top portions of the supporting shafts, and the pedals are eccentrically arranged relative to the supporting shafts; and the synchronizing assembly is arranged between the two supporting shafts and enables the two supporting shafts to act synchronously. The application is rational in overall structural design, and utilizes a coordination effect of a body and movement trajectories of legs during skating, an apparatus is designed accordingly, and location simulation is-formed between the two pedals through the synchronizing assembly. The application can also be provided with an electric driver to assist a human body with rehabilitation training, or can be provided with a resistance adjusting assembly to improve the fitness effect and intensity.

Abstract: The invention provides a mobile networking method and system for minimizing interference. The mobile networking method comprises the following steps: unmanned aerial vehicles establish connection and communication with ground base stations through a wireless relay method; connection and communication between the unmanned aerial vehicles are established through a wireless self-networking method; multiple unmanned aerial vehicles cooperate to form a cellular network to provide wireless network services for users; the unmanned aerial vehicles receive a received signal strength indicator fed back by an user equipment and measure an angle of arrival of a signal beam from the user equipment; the main lobe of a signal is made to aim at the direction of arrival of service users through a mobile interference alignment method and a beam forming method thus enabling the optimal hovering position of the unmanned aerial vehicle to be obtained.

Abstract: The invention provides a mobile networking method and system for minimizing interference. The mobile networking method comprises the following steps: unmanned aerial vehicles establish connection and communication with ground base stations through a wireless relay method; connection and communication between the unmanned aerial vehicles are established through a wireless self-networking method; multiple unmanned aerial vehicles cooperate to form a cellular network to provide wireless network services for users; the unmanned aerial vehicles receive a received signal strength indicator fed back by user equipment and measure the angle of arrival of a signal beam from the user equipment; the main lobe of a signal is made to aim at the direction of arrival of service users and the null is made to aim at the direction of arrival of interference signals through a mobile interference alignment method and a beam forming method, and thus the optimal hovering position is searched out.