A new technology for production of high purity paratungstate ammonium from low grade tungsten concentrateSpringer Science and Business Media LLC - Tập 3 - Trang 171-176 - 1996
Peimei Sun, Zhouxi Chen, Honggui Li, Yunjiao Li, Maosheng Liu, Shuqiao Chen, Yongtang Liang
A new technological process for production of paratungstate ammonium from low grade tungsten concentrate with a high content of calcium and impurities has been studied. The experiments show that average tungsten leaching efficiency of more than 96.92% can be obtained with a low NaOH consumption by using the mechanical activating caustic decomposition, and the content of main impurities (P, As, Si)...... hiện toàn bộ
Optimization analysis on gap size of molding for Pb-GF composite wireSpringer Science and Business Media LLC - Tập 12 - Trang 17-21 - 2005
Wen-bin Fang, Hong-fei Sun, Yao-hong Geng, Er-de Wang, Fei Han
Under the condition of equal flow, the maximum and minimum theoretical values of gap size were studied and an estimation equation was established for the clad extrusion of the brittle core cladded by plastic metal materials. The results show that the gap size is a key parameter for the continuous clad extrusion and the molding speed. Its maximum value (H
max) is 0.24 mm and the minimum one (H
min)...... hiện toàn bộ
Finite element simulation of influences of grain interaction on rolling textures of fcc metalsSpringer Science and Business Media LLC - - 2006
Jian-guo Tang, Xin-ming Zhang, Zhi-yong Chen, Yun-lai Deng
A rate dependent crystal plasticity constitutive model considering self and latent hardening in finite element analysis was developed to simulate rolling textures of pure aluminum. By changing the assignment of orientations to finite elements, i. e. assigning the same set of orientations to all elements or different orientations to different elements, the influences of grain interaction on the for...... hiện toàn bộ
Study on syntheses and characterizations of polymethylphenethylsilane, polymethylcyclohexylsilane and their copolymersSpringer Science and Business Media LLC - - 2000
Hui-ping Hu, Ke-long Huang, Chun-yue Pan, De-ben Chen
The effects of adding cosolvents of diglyme and 15-crown-5 to the reaction mixture of Wurtz-type coupling of dichlorosilanes on the yield and relative molecular mass dispersity of polymethylphenethylsilane(PMPES) were discussed. The results show that addition of 10% (volume ratio of diglyme to toluene) diglyme as a cosolvent to the reaction mixture leads to the yield increase of PMPES with a monom...... hiện toàn bộ
Estimation of compaction grouting pressure in strain softening soilsSpringer Science and Business Media LLC - Tập 16 - Trang 653-657 - 2009
Xiao-li Yang, Jin-feng Zou
A new method was proposed to predict the limited compaction grouting pressure for the soft soils. Theoretical basis of the method considered the conical shear failure above the grout bulb. Using the Mohr-Coulomb yield criterion as the initial yield function, the limited compaction grouting pressure was determined, according to the softening elastic-plastic model based on the conventional triaxial ...... hiện toàn bộ
Identification of structure and parameters of rheological constitutive model for rocks using differential evolution algorithmSpringer Science and Business Media LLC - Tập 15 - Trang 25-28 - 2010
Guo-shao Su, Xiao-fei Zhang, Guang-qiang Chen, Xing-yi Fu
To determine structure and parameters of a rheological constitutive model for rocks, a new method based on differential evolution (DE) algorithm combined with FLAC3D (a numerical code for geotechnical engineering) was proposed for identification of the global optimum coupled of model structure and its parameters. At first, stochastic coupled mode was initialized, the difference in displacement bet...... hiện toàn bộ
Microstructures and mechanical properties of Mg-Ce-Zn-Zr wrought alloySpringer Science and Business Media LLC - Tập 11 - Trang 367-370 - 2004
Wen-hua Wu, Chang-qing Xia
Microstructures and mechanical properties of Mg-2.0%Ce-0.7%Zn-0.7%Zr alloy were studied. The results of scanning electron microscopy show that Mg12Ce phase mainly distributes at the grain boundaries. The fine Mg12Ce phase can apparently elevate recrystallization temperature by preventing the grain boundary migration. No dynamic recrystallization occurs during the hot-extrusion. The mechanical prop...... hiện toàn bộ