The main aggregation pheromone component(1)of stored grain pest,Cryptolestes Pusillus, was synthesized with organosilicon and organolithium reagents in an overall yield of 18% from 1,7- heptanediol.
The mass fiat raft foundation Section is large and Cement is in large quantities, the temperature changes in the larger cement hydration heat of the water releasing, the temperature stress is main reason reducing crac...The mass fiat raft foundation Section is large and Cement is in large quantities, the temperature changes in the larger cement hydration heat of the water releasing, the temperature stress is main reason reducing cracking. According to the basement of a project of Guangzhou large slab raft foundation engineering as an example, Discussing the construction technology measures of early crack of large volume concrete of raft plate in the process of construction,. The results show that it Can effectively prevents the slab foundation structure cracking and achieves good results through controlling Concrete materials and concrete temperature Parameter such as the lifting machine temperature and the pouring temperature and the expansion joint or the whole pouring length.展开更多
The theory of stochastic equations and the theory of equivalence of measures previously applied to flows in the boundary layer and in the pipe are considered to calculate the velocity profile of the flat jet.This theo...The theory of stochastic equations and the theory of equivalence of measures previously applied to flows in the boundary layer and in the pipe are considered to calculate the velocity profile of the flat jet.This theory previously made it possible to determine the critical Reynolds number and the critical point for the flow of the plane jet.Here based on these results the analytical dependence for the index of the velocity profile is derived.Velocity profiles are calculated for a laminar-turbulent transition in the jet.This formula reliably reflects an increase of the energy transferred from a deterministic state to a random one with an increase of the index of the velocity profile.Results show satisfactory agreement with the known experimental data for the velocity profile of the flat jet.Using obtained results it is possible to determine the location of technical devices for laminarization of the flow in the jet.This is important both for reducing friction in the flow around aerodynamic vehicles and for maintaining the jet profile if it is necessary to ensure the stability of the flow characteristics.Also the obtained relations can be useful for researching of the processes in combustion chambers,in the case of welding and in other technical devices.展开更多
文摘The main aggregation pheromone component(1)of stored grain pest,Cryptolestes Pusillus, was synthesized with organosilicon and organolithium reagents in an overall yield of 18% from 1,7- heptanediol.
文摘The mass fiat raft foundation Section is large and Cement is in large quantities, the temperature changes in the larger cement hydration heat of the water releasing, the temperature stress is main reason reducing cracking. According to the basement of a project of Guangzhou large slab raft foundation engineering as an example, Discussing the construction technology measures of early crack of large volume concrete of raft plate in the process of construction,. The results show that it Can effectively prevents the slab foundation structure cracking and achieves good results through controlling Concrete materials and concrete temperature Parameter such as the lifting machine temperature and the pouring temperature and the expansion joint or the whole pouring length.
文摘The theory of stochastic equations and the theory of equivalence of measures previously applied to flows in the boundary layer and in the pipe are considered to calculate the velocity profile of the flat jet.This theory previously made it possible to determine the critical Reynolds number and the critical point for the flow of the plane jet.Here based on these results the analytical dependence for the index of the velocity profile is derived.Velocity profiles are calculated for a laminar-turbulent transition in the jet.This formula reliably reflects an increase of the energy transferred from a deterministic state to a random one with an increase of the index of the velocity profile.Results show satisfactory agreement with the known experimental data for the velocity profile of the flat jet.Using obtained results it is possible to determine the location of technical devices for laminarization of the flow in the jet.This is important both for reducing friction in the flow around aerodynamic vehicles and for maintaining the jet profile if it is necessary to ensure the stability of the flow characteristics.Also the obtained relations can be useful for researching of the processes in combustion chambers,in the case of welding and in other technical devices.
