The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature a...The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature and well-developed. One of the advanced uses is for reversing a car and it is based on sending sound waves through a specific medium and observing the returning echoes to measure the distance from the device to the obstacle. In this report, a simple ultrasonic distance measurement system will be introduced including the design of hardware and software, the simulating results and the final product. This system was built to be cheaper, requires less power and delivers better performance.展开更多
Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom...Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom in capillary zone electrophoresis. The reason is due to the reduction of the average apparent mobilities of the analytes.展开更多
This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the econom...This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the economic andtechnological development zones to follow the“pattern of the special zones”,but a new pattern of“small scale,unitaryfunction and closeness to old city”should be adopted to fit in with the practical conditions in our country.The scale,landuse structure and the relations between the development zone and the old city are the basic issues in planning forthe development zones.These three essential elements constitute the pattern of planning which determines to a certainextent the success or failure of the development zones.展开更多
文摘The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature and well-developed. One of the advanced uses is for reversing a car and it is based on sending sound waves through a specific medium and observing the returning echoes to measure the distance from the device to the obstacle. In this report, a simple ultrasonic distance measurement system will be introduced including the design of hardware and software, the simulating results and the final product. This system was built to be cheaper, requires less power and delivers better performance.
文摘Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom in capillary zone electrophoresis. The reason is due to the reduction of the average apparent mobilities of the analytes.
文摘This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the economic andtechnological development zones to follow the“pattern of the special zones”,but a new pattern of“small scale,unitaryfunction and closeness to old city”should be adopted to fit in with the practical conditions in our country.The scale,landuse structure and the relations between the development zone and the old city are the basic issues in planning forthe development zones.These three essential elements constitute the pattern of planning which determines to a certainextent the success or failure of the development zones.
