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The coal gangue are produced in a coal mine heap of Pan xian, Gui zhou, by using microwave assisted acid leaching methods and under certain reaction conditions, the products of different stages of acid leaching were characterized through different characterization methods like X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy. The related process mechanism of Microwave assisted technique acid leaching gangue was preliminarily studied by the characterization results from analyzing the products of different stages of acid leaching.

Static adsorption experiments were conducted to understand the impact of soil surface charge characteristics, such as pH, AEC and CECp values, on migration behavior of radioactive Uranium, Strontium and Cesium. The results demonstrate that distribution coefficient of Uranium (U-Kd value) increases with decreasing initial pH of solution, and increases with increasing AEC values for acidic clay and silty clay that were studied; distribution coefficients of Strontium and Cesium appear to be positively correlated with CECp values of and total contents of montomorillonite and illite in the soil.

Advantages and disadvantages of natural shields in a very low level waste (VLLW) disposal area were studied with regard to the adsorption and fixation capability of the natural shields against radioactive elements Uranium, Strontium and Cesium, with the understanding of the hydrogeological and geochemical characteristics of the surrounding area. Necessity of establishing geochemical engineering shield in the disposal area is discussed based on the understanding of the inadequacy of the natural shields against Uranium and Strontium. A physical chemistry model involving three-fold of shields suitable for the disposal area is proposed with integrated consideration of the results from efficacy and endurance experiments on the natural shield.

The composition, the texture and structure, the mineralogical characteristics of major minerals, the main occurrences of major elements and the distribution rules of vanadium titanium magnetite of Hongge area, Panzhihua, Sichuan Province of China, were studied in details by the methods of chemical multi-elements analysis, optical microscope, scanning electron microscope (SEM), electron probe micro-analysis (EPMA), X-ray diffraction (XRD) and X-ray fluorescence (XRF). The study results provide references to the vanadium titanium magnetite beneficiation process of this mining area.

This paper studied the concentration distribution of gas extinguishing agent numerically in high velocity flow field. Civil aircraft power plant compartment has been a difficult area for its high velocity flow field formed after fire happens. Focusing on this issue, certain results, such as mass flow rate of agent gas, total mass of agent and extinguishing efficiency were presented. A typical apparatus of fire extinguishing system was set up, and its fire-fighting efficiency was evaluated. Critical ratio of mass flow rate and flow velocity, gas discharge time and locations of gas sample tubes were recommended. The results and data can provide a practical way in fire extinguishing system evaluation in civil aircraft power plant compartment.

Neutral point grounding method with an arc suppression coil and a parallel resistance is a method that can inhibit arc overvoltage effectively. Through the simulation of arc suppression coil with parallel resistance in the situation of different resistance value, we can obtain if the parallel resistance is too big, it will produce overvoltage in the later of voltage recovery; if the parallel resistance is too small, it is easy to produce larger grounding residual flow, going against quenching of arc; Whether over compensation or owe compensation, oversized out-of-resonance degree will cause the fault phase voltage recovery oscillation overvoltage, small out-of-resonance degree is beneficial to the fault phase voltage rise slowly.