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401.
- The characteristics of deformation and strength of concrete under the plane strain condition are studied experimentally with the triaxial apparatus designed by the authors and are compared with those under the plane stress condition. A formula of stress transformation between plane stress and plane strain conditions is proposed for the elasto-plastic state, and it provides a theoretical basis for simplifying nonlinear analysis and fully using the strength of concrete. 相似文献
402.
Ma Liang Wang Jinying Xing Zhizhuang Sun Shaoshu
Professor Dalian University Dalian Senior Engineer China Offshore Oil Engineering Co. 《中国海洋工程》1994,(2)
- This article is aimed at the experimental study of the hydrodynamic loading induced by waves and current acting on the JZ 20-2 submarine composite pipelines. The corresponding hydrodynamic coefficients obtained in this experimental study can be applied to engineering projects. 相似文献
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1. Previous works on microscopy of anthracite. The existing method of coal petrography seems to be well adaptableonly to bituminous or lignitic coals; in the case of anthracite,because of itsextreme opacity to light and resistency to most chemical solvent 相似文献
407.
Professor Dr. Kurt Spangenberg Martha Müller 《Contributions to Mineralogy and Petrology》1949,1(5-6):560-572
Ohne ZusammenfassungAbgeschlossen im Juni 1947. 相似文献
408.
Professor Dr. Kurt Spangenberg Z. Heidenheim 《Contributions to Mineralogy and Petrology》1949,1(5-6):535-547
Ohne ZusammenfassungAbgeschlossen im Juni 1947. 相似文献
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M. R. Samarghandi M.R. M.Sc. Ph.D. J. Nouri Associate professor A. R. Mesdaghinia Professor Chairman A. H. Mahvi Associate professor S. Nasseri Professor F. Vaezi Associate professor 《International Journal of Environmental Science and Technology》2007,4(1):19-25
A variety of processes can be used in treatment of industrial wastewaters. The relatively newest of which is photo catalysis with titanium dioxide which may also be used plus hydrogen peroxide to improve the treatment rate. In this study, photo catalysis/ hydrogen peroxide processes had been employed for the removal of phenol, lead and cadmium by three different pHs of 3.5, 7 and 11. The treatment tests were also accomplished without UV irradiation. In both experiments, the variables were pH and concentrations of reagent chemicals, but the detention time was kept constant (180 min). Results indicated that the optimum efficiencies of phenol and Cd removal were 76 % and 97.7 % at pH=11, respectively, and for lead, it was 98.8% in all pHs. In other words, no pH dependency was regarded for lead treatment. These results were all obtained by simultaneous use of UV irradiation with 3 mL/L H2O2 and 0.8 g/L TiO2. Finally, the best pH for treatment, when all the three contaminants are presented is considered to be at 11. These results should be regarded by all industrial treatment plants which have experienced the problem of these three special contaminants in their effluents. 相似文献