Abstract: A manganese-based carbonate precursor of a positive electrode material for a secondary battery has a specific structure and composition and contains a trace amount of uniformly distributed Na element, a content of Na is in a range of 0.5-3 mol %, which range can ensure that the structural integrity and consistency of carbonate crystals are not affected. In addition, the trace amount of Na element is uniformly distributed inside the manganese-based carbonate precursor provided in the present application, and by means of simple mixing with a lithium source and sintering, a lithium-rich manganese-based material uniformly doped with Na element can be directly obtained without the need for introducing other Na source, whereby uneven doping of Na is effectively avoided, the doping effect is improved, and the electrical properties of the material are significantly improved.

Abstract: This is an early identification method for a shallow soil landslide, belonging to the technical field of landslide prevention and control engineering. The present invention accurately determines and identifies a shallow soil landslide in a quantitative manner, improving the early identification efficiency of a landslide and helping to improve the disaster prevention effect.

Abstract: This is an early warning method for a shallow soil landslide based on a digital topographic map, belonging to the field of landslide prevention and control engineering. It has following steps: a. connecting a straight line along an upward bulged intermediate point of a contour line of the topographic map as an intermediate line; b. determining an intermediate point; c. constituting a three-point group of a plane curvature; d. taking an arithmetic average of slopes as a slope ? of a landslide mass. The shallow soil landslide can be early warned without a lot of historical observation data of landslide occurrence, and the dangerous landslide mass can be determined in advance, which greatly improves the applicability of disaster prevention and the early warning efficiency.

Abstract: Disclosed is an early warning method for a shallow soil landslide based on a digital topographic map, belonging to the field of landslide prevention and control engineering. The method is characterized by comprising the following steps: a. connecting a straight line along an upward bulged intermediate point of a contour line of the topographic map as an intermediate line; b. determining an intermediate point; c. constituting a three-point group of a plane curvature; d. taking an arithmetic average of slopes as a slope a of a landslide mass; e. according to the distribution principle of topographic DEM data, assigning all points in each grid with the same values; f. taking an arithmetic average; g. calculating a topographic factor T of a potential landslide mass; h. calculating a rainfall factor R; i. calculating an early warning determination value P of the shallow soil landslide; j. performing early warning according to the early warning determination value P of the shallow soil landslide.

Abstract: This is an early identification method for a shallow soil landslide, belonging to the technical field of landslide prevention and control engineering. The present invention accurately determines and identifies a shallow soil landslide in a quantitative manner, improving the early identification efficiency of a landslide and helping to improve the disaster prevention effect.

Abstract: A bio-trickling filter box device capable of purifying organic wastewater and generating electricity is provided, which includes battery component(s) and a bio-trickling filter box component. The battery component(s) is provided in the bio-trickling filter box. The other end of each of trickling filter tube(s) is connected with a water tank. A water pump operates to make water flow through the trickling filter tube(s), pass through leakage holes and trickling holes, and drip into the battery component(s) in a water-drop manner, so as to supply an electric apparatus component with power. The bio-trickling filter box component(s) and the battery component(s) are combined, and the long-term impingement of water droplets on the battery component(s) can accumulate electric charge and generate the electricity. so as to provide power required by the electric apparatus component, which forms a biological treatment system that generates the power while treating the wastewater.

Abstract: A bio-trickling filter box device capable of purifying organic wastewater and generating electricity is provided, which includes battery component(s) and a bio-trickling filter box component. The battery component(s) is provided in the bio-trickling filter box. The other end of each of trickling filter tube(s) is connected with a water tank. A water pump operates to make water flow through the trickling filter tube(s), pass through leakage holes and trickling holes, and drip into the battery component(s) in a water-drop manner, so as to supply an electric apparatus component with power. The bio-trickling filter box component(s) and the battery component(s) are combined, and the long-term impingement of water droplets on the battery component(s) can accumulate electric charge and generate the electricity. so as to provide power required by the electric apparatus component, which forms a biological treatment system that generates the power while treating the wastewater.