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Peng X.-R.,Hunan Chemical Vocational Technology College
Proceedings - 2013 4th International Conference on Digital Manufacturing and Automation, ICDMA 2013

With outside disturbing effects, large hydraulic straightening machine's total load changes intricately and its precision is less than ideal requirements when being straightened. This paper preposes the fuzzy control strategy, and realizes high-precision control of the straightening machine. © 2013 IEEE. Source

Ying T.,Hunan Chemical Vocational Technology College
Proceedings - 2013 4th International Conference on Digital Manufacturing and Automation, ICDMA 2013

This thesis further study descent conjugate gradient methods based on the modified FR method and the modified PRP method give the class of conjugate gradient methods formed by the convex combination of the MFR method and the MPRP method. This class of methods enjoys the same nice properties as those of the MFR method and the MPRP method. Firstly the methods generate sufficient descent directions for the objective function. This property is independent of the line search used. Secondly if exact line search is used, the methods possess quadratic termination property. Thirdly if Armijo type line search is used, then the methods are globally convergent when used to minimize a general nonconvex function. Finally, we do extensive numerical experiments to test the performance of the members in the class with different parameters. And then compare the performance of one of the method in the class with the MFR method and the MPRP method. © 2013 IEEE. Source

Li J.,Hunan Chemical Vocational Technology College
Advanced Materials Research

In this paper, a precipitation method is investigated to prepare nanoscale zinc oxide (ZnO) as the precursor of silver coated antibacterial nanocomposite. Subsequently, silver loadeded zinc oxide nanocomposites (ZnO/Ag) are prepared by hydrolysis method. The average diameters and morphology of ZnO nanocomposites before and after silver loaded were compared. The results showed that the zinc oxide powder presented good dispersibility and uniform size a average diameter of 170 nm. Silver was coated on the precursor successfully, and the diameter of ZnO nanocomposites increased slightly. Source

Zhang R.-L.,Jiangsu University of Science and Technology | Tang S.-Z.,Hunan Chemical Vocational Technology College
Materials Science Forum

PbS nanocrystals was synthesized by a heterogeneous reaction of hydrogen sulfide gas and lead nitrate solution containing EDTA in ethanol. The influenceof initial molar concentration ratio of EDTA/Pb(NO3)2 (CEDTA/CPb(NO3)2), volume ratio of ethanol/water (Vethanol/VH2O), pH value and flux of H2S on the particle size of PbS were investigated. The structure, morphology, particle size, and particle size distribution ranges of PbS were characterized by XRD, FE-SEM, and laser particle size analyzer, respectively. Increasing CEDTA/CPb(NO3)2, Vethanol/VH2O, and pH value, as well as decreasing the flux of H2S decrease the particle size of PbS. PbS nanocrystals have an average particle size of 69 nm, a narrow size distribution, and a quasi-spherical shape when CEDTA/CPb(NO3)2 is 1, Vethanol/VH2O is 1, pH is 3.5, and the flux of H2S is 20 ml/min. © (2015) Trans Tech Publications, Switzerland. Source

Xia Y.,Hunan Chemical Vocational Technology College
Advanced Materials Research

Industry is the foundation of national economy and military development, and machinery manufacture and production is the main content of industry. Therefore, each country attaches great importance to its own machinery manufacture capacity and production levels. Influenced by the special historical factors, China's economy started relatively late, with a low machinery manufacture capacity. To essentially change this phenomenon, the selection and processing technology of metal materials must be optimized. This paper analyzes the concept and characteristics of metal mechanics, together with the present situation of China's machinery manufacture and production. After studying the relationship between metal mechanical and machinery manufacture and production, it is found that the use of metal mechanics can improve the quality of mechanical products. © (2013) Trans Tech Publications, Switzerland. Source

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