The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on t...The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on the surface layer model was established by introducing the scale parameters and modifying the classical Hall-Petch equation. The influence of the geometric dimensions and the grain size on the flow behavior of the material was discussed using the new material constitutive model. The results show that, the flow stress decreases while the sheet metal thickness decreases when the grain size keeps constant, and the micro-sheet metal with a larger grain size is more easily to be influenced by the size effects. The material constitutive model established is validated by the stress-strain curve of the micro-sheet metal with different thicknesses derived from the tensile experiments. The rationality of the material model is verified by the fact that the calculation results are consistent with the experimental results.展开更多
A wet impact crusher was used to breakdown waste printed circuit boards （PCB＇s） in a water medium. The relationship between the yield of crushed product and the operating parameters was established. The crushing me...A wet impact crusher was used to breakdown waste printed circuit boards （PCB＇s） in a water medium. The relationship between the yield of crushed product and the operating parameters was established. The crushing mechanism was analyzed and the effects of hammerhead style, rotation speed, and inlet water volume on particle size distribution were investigated. The results show that the highest yield of -1 ＋ 0.75 mm sized product was obtained with an inlet water volume flow rate of 5.97 m3/h and a smooth hammerhead turning at 1246.15 r/rain. Cumulative undersize-product yield curves were fitted to a nonlinear function： the fitting correlation coefficient was greater than 0.998. These research results provide a theoretical basis for the highly effective wet crushing of PCB＇s.展开更多
Active exploitation of solar energy is achieved in systems that absorb this energy through flat collectors. Hot water can be used for space heating, when its temperature is high, but it is used largely for DHW （domes...Active exploitation of solar energy is achieved in systems that absorb this energy through flat collectors. Hot water can be used for space heating, when its temperature is high, but it is used largely for DHW （domestic hot water） needs. Now days, this technology has resulted as the most viable for exploitation of solar energy, and various countries such as Israel, Turkey, and Greece provide hot water for residential and service sectors using systems of solar panels. In this proceeding we are writing about the dimension of the solar panels surface based to the net present value in Hotels of Albania.展开更多
基金Project(50975163)supported by the National Natural Science Foundation of ChinaProject(IRT0931)supported by Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China
文摘The inherent mechanism of size effect in micro-sheet material behavior of plastic forming was explained by the surface layer model and theory of metal crystal plasticity. A size-dependant constitutive model based on the surface layer model was established by introducing the scale parameters and modifying the classical Hall-Petch equation. The influence of the geometric dimensions and the grain size on the flow behavior of the material was discussed using the new material constitutive model. The results show that, the flow stress decreases while the sheet metal thickness decreases when the grain size keeps constant, and the micro-sheet metal with a larger grain size is more easily to be influenced by the size effects. The material constitutive model established is validated by the stress-strain curve of the micro-sheet metal with different thicknesses derived from the tensile experiments. The rationality of the material model is verified by the fact that the calculation results are consistent with the experimental results.
基金financially supported by the National Natural Science Foundation of China for Creative Research Groups Science Foundation (No.50921002)the National Natural Science Foundation of China (Nos.50574094 and 51074156)+2 种基金the China Postdoctoral Science (No.20090461153)the China Postdoctoral Science Foundation funded projects in particular (No.201003607)the Key Laboratory for Solid Waste Management and Environment Safety Open Foundation (No.swmes-2010-08)
文摘A wet impact crusher was used to breakdown waste printed circuit boards （PCB＇s） in a water medium. The relationship between the yield of crushed product and the operating parameters was established. The crushing mechanism was analyzed and the effects of hammerhead style, rotation speed, and inlet water volume on particle size distribution were investigated. The results show that the highest yield of -1 ＋ 0.75 mm sized product was obtained with an inlet water volume flow rate of 5.97 m3/h and a smooth hammerhead turning at 1246.15 r/rain. Cumulative undersize-product yield curves were fitted to a nonlinear function： the fitting correlation coefficient was greater than 0.998. These research results provide a theoretical basis for the highly effective wet crushing of PCB＇s.
文摘Active exploitation of solar energy is achieved in systems that absorb this energy through flat collectors. Hot water can be used for space heating, when its temperature is high, but it is used largely for DHW （domestic hot water） needs. Now days, this technology has resulted as the most viable for exploitation of solar energy, and various countries such as Israel, Turkey, and Greece provide hot water for residential and service sectors using systems of solar panels. In this proceeding we are writing about the dimension of the solar panels surface based to the net present value in Hotels of Albania.
