Aviation fuel is in great demand globally. The increased demand and high price for energy sources are driving efforts to convert natural non-renewable organic compounds into useful hydrocarbon fuel materials such as i...Aviation fuel is in great demand globally. The increased demand and high price for energy sources are driving efforts to convert natural non-renewable organic compounds into useful hydrocarbon fuel materials such as in form of aviation fuel. Alternate sources to these non-renewable hydrocarbon fuels are important and necessary. Much of these alternative sources are focused on biomass however, there are strong benefits of deriving fuels from waste plastic materials. Thermal processes can be used to convert waste plastics into hydrocarbon fuels like aviation fuel, which have unlimited applications in airline industries, as well as in transportation and power generation industries. These thermal processes are used to break down the long carbon chains found in plastics into the shorter chains in a temperature range from 300-450 ℃. This method has been carried out in succession in previous experiments. This simple and economically viable process has been developed to convert the hydrocarbon polymers of waste plastics into the short and medium chain hydrocarbons of liquid fuels. Based on the initial characterization, a fractionated portion of the developed fuel shows properties similar to some of the commercially available aviation fuels.展开更多
Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses...Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.展开更多
文摘Aviation fuel is in great demand globally. The increased demand and high price for energy sources are driving efforts to convert natural non-renewable organic compounds into useful hydrocarbon fuel materials such as in form of aviation fuel. Alternate sources to these non-renewable hydrocarbon fuels are important and necessary. Much of these alternative sources are focused on biomass however, there are strong benefits of deriving fuels from waste plastic materials. Thermal processes can be used to convert waste plastics into hydrocarbon fuels like aviation fuel, which have unlimited applications in airline industries, as well as in transportation and power generation industries. These thermal processes are used to break down the long carbon chains found in plastics into the shorter chains in a temperature range from 300-450 ℃. This method has been carried out in succession in previous experiments. This simple and economically viable process has been developed to convert the hydrocarbon polymers of waste plastics into the short and medium chain hydrocarbons of liquid fuels. Based on the initial characterization, a fractionated portion of the developed fuel shows properties similar to some of the commercially available aviation fuels.
文摘Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.
