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In this paper, Bacterial oxidation-cyanide leaching experiments were carried out and the carbonaceous substances composition of carbonaceous gold concentrate was been studied. The elemental composition was 9.73 % iron, 9.66 % sulfur, 4.84 % arsenic and 13.23 % carbon which element carbon and organic carbon was 12.11wt.% and 0.06 wt.% respectively. The main carbonaceous substances were elemental carbon which the morphology was dense and similar to graphite. The removal rates of iron, arsenic and sulfur were achieved to 93.78%, 97.02% and 95.54% respectively by bioleaching, and the gold recovery of oxidation residue reached 92.34% by carbon inhibited cyanide leaching process. The sulfide minerals packing problem could be effectively solved by bacterial oxidation process and greatly increased the gold recovery. So the bacteria oxidation and carbon inhibited leaching process is applicable to the carbonaceous gold ore.

This paper is mainly aimed at the problem of low bonding strength of soy bean protein adhesive,poor water resistance,with methyl methacrylate and vinyl acetate composite study made with rubber manufacturing class II plywood,meet the national standard,so as to solve the water resistance of soy protein adhesives and bonding strength of.Experiments that 3.5g soy protein, 5g PVA, 30g MMA, 0.3g APS and 100g water, modified soy protein adhesive bonding strength obtained is excellent, and cost reduction.Preparation of soybean protein-acrylate adhesive solid content,viscosity and strength of plywood detection.

Mineralogical examinations of Asheler copper mine flotation tailings have been carried out. Results show that the major metal sulphide minerals are pyrite and the main gangue constituents are quartz, chlorite-serpentine and muscovite. The main valuable metals are Cu, Zn and Ag. Basic mineral compositions of copper and zinc have been identified through chemical phase analysis. On the basis of mineralogical examinations, leaching test has been carried out in about 240g/l NaCl solution. The optimum conditions for leaching are found as follows: temperature at 86°C, pulp concentration is 24.19%wt, [Cu2+] =19.22g/l, [HCl] initial =0.17mol/L. Under these conditions, chloride leaching can extract 83.35%Cu, 92.10%Zn, and 85.26%Ag after 8 hours leaching.

Three commercial extractants LIX984N, LIX606N and LIX973N were chosen for the research on Cu2+extraction from the solutions bearing high concentration of sulfuric acid and iron. The ability of Cu2+extraction and Cu/Fe separation performance were totally compared among the three extractants. The results show that LIX606N and LIX973N both possess more powerful ability in Cu2+extraction as compared to LIX984N. But, LIX973N and LIX984N has better Cu/Fe separation performance than LIX606N. According to the performance of Cu2+extraction and Cu/Fe separation, LIX973N is more suitable for extracting Cu2+from the solution rich in sulfuric acid and Fe3+.Effects of sulfuric acid and Fe3+concentration on Cu2+extraction by 20%LIX973N-kerosene have been examined. When aqueous sulfuric acid concentration increases from 23.48g/L to 62.16g/L, Cu2+extraction recovery drops from 60.42% to 25.21%; When aqueous Fe3+concentration increases from 7.03g/L up to 42.94g/L, Fe3+concentration in organic phase increases from 0.26g/L to 0.82g/L.

Electrochemical impedance (EI) plays a very important role on the characteristics of proton exchange membrane (PEM) fuel cell. In this paper, the effects of the cell temperature and the humidification temperature on the electrochemical impedance are analyzed by the equivalent circuit. The results show: when the cell temperature is higher than the gas humidification temperature, ohms impedance and Faraday impedance increase markedly, and electric double layer in the PEM fuel cell inclines to the specialty of capacitive reactance; the more than the cell temperature the gas humidification temperatures is, the more the extent of specialty of capacitive reactance the electric double layer shows. These results are very helpful to understand the operating principle of PEM fuel cell and improve its performance.

Proton exchange membrane (PEM) fuel cell is a clean electrochemical device with great prospect of application. Performance plays an important role in the application of PEM fuel cell. In this paper, a voltage characteristics model of PEM fuel cell is established, its performance curves is simulated, and the influence of the operating parameters on its performance is analyzed. The results show that the simulated performance curves of PEM fuel cell and its experimental performance curves have a high degree of agreement; when the cell temperature is lower than the gas humidification temperature, the drooping extent in the high current density section of performance curve increases with the increase of the gas humidification temperatures. When the cell temperature is equal to or higher than the gas humidification temperature, the slope of the straight line section of the performance curve decreases with the increase of the gas humidification temperatures. The performance curve of the PEM fuel cell goes up with the increase of reaction gas pressure. The results are very helpful to optimization and application of PEM fuel cell.

The electrode structure, especially for the channel depth, plays an important role on the performance of the proton exchange membrane (PEM) fuel cell. In this paper, the performance and electrochemical impedance of the PEM fuel cell are measured experimentally. The simulation results of mass transfer and equivalent circuit for the electrochemical impedance are used to explain the effect of the channel depth on the performance of the PEM fuel cell. These results show that when the cell temperature is lower than the gas humidification temperatures, the performance of PEM fuel cell with the channel depth of 2mm is better than that of 1mm; there is more liquid water saturation in cathode for the channel depth of 1mm than that for the channel depth of 2mm. The charge transfer resistance of the PEM fuel cell with the channel depth of 2mm is less than that with the channel depth of 1mm. These results are very helpful to optimizing structure of the PEM fuel cell.

Electrode structure plays an important role on performance of the proton exchange membrane (PEM) fuel cell. A two-dimensional, two-phase flow model is presented to simulate the performance of PEM fuel cell with direct flow fields and its mass transfer in cathode in this paper. Effects of depth and width of channel and depth of gas diffusion layer on the performance of PEM fuel cell and mass transfer in its cathode are analyzed. The results show that electrode structure affects strongly the performance of fuel cell and mass transfer in its electrode; when depth of channel is 0.75mm, there are the worst performance and mass transfer; decreases of the width of the channel and depth of the gas diffusion layer are beneficial to improving mass transfer and increase performance of PEM fuel cell. These results are very helpful for optimization of PEM fuel cells.