Abstract: The present disclosure provides a method for testing an internal force increment of an arch bridge suspender by inertial measurement, including the following steps: (1) selecting a suspender to be tested with internal force increment, and mounting an acceleration sensing device or a speed sensing device at a lower edge of the suspender to be tested; (2) setting an appropriate sampling frequency and collecting signals; (3) processing information data collected in step (2) by using Formulas; and (4) recording a result of the information data processing and obtaining the internal force increment of the suspender. The method can obtain the internal force increment of the suspender by collecting acceleration or speed signals of the lower edge of the suspender and performing calculation from the signals. This method has the advantages of simple and convenient testing, high replicability and low test cost.

Abstract: A method for treating fluorine-containing rare earth mineral particles may include mixing a first batch of the fluorine-containing rare earth mineral particles with a first sulfuric acid solution in a weight ratio in the range of 2-10:1 of the sulfuric acid in the first sulfuric acid solution to the first batch of fluorine-containing rare earth mineral particles, and heating the mixture to cause a liquid-solid reaction. The solid phase and liquid phase may be separated after the reaction to obtain an acid filtrate and an acid residue. The acid residue may be leached with water to obtain an aqueous leaching liquor that comprises a rare earth sulfate and an aqueous leaching residue. A second sulfuric acid solution may be added to the acid filtrate in an amount such that the sulfuric acid concentration of the acid filtrate is 40-85 wt %.

Abstract: A method for treating fluorine-containing rare earth mineral particles may include mixing a first batch of the fluorine-containing rare earth mineral particles with a first sulfuric acid solution in a weight ratio in the range of 2-10:1 of the sulfuric acid in the first sulfuric acid solution to the first batch of fluorine-containing rare earth mineral particles, and heating the mixture to cause a liquid-solid reaction. The solid phase and liquid phase may be separated after the reaction to obtain an acid filtrate and an acid residue. The acid residue may be leached with water to obtain an aqueous leaching liquor that comprises a rare earth sulfate and an aqueous leaching residue. A second sulfuric acid solution may be added to the acid filtrate in an amount such that the sulfuric acid concentration of the acid filtrate is 40-85 wt %.