A microcomputer-based UV/V in situ spectroelectrochemical measurement system has been developed.This paper presents a description of the experimental details regarding the methods and equipment.
Accurate aerodynamic measurements in the hypersonic flow of large aircraft models in tunnels have practical significance, but pose a significant challenge. Novel aerodynamic force measurement methods have been propose...Accurate aerodynamic measurements in the hypersonic flow of large aircraft models in tunnels have practical significance, but pose a significant challenge. Novel aerodynamic force measurement methods have been proposed,but lack theoretical support. The forms of the force signals techniques for signal processing and calculation of aerodynamics are especially problematic. A theoretical study is conducted to investigate the dynamic properties based on models of the draw-rod system and slender rods. The results indicate that the inertia item can be neglected in the rod governing equation;further, the solutions show that the signals of each rod are a combination of aerodynamic signals(with a constant value) and sine signals, which can be verified by experimental shock tunnel results. Signal processing and aerodynamics calculation techniques are also found to be achievable via the flat part of the signals.展开更多
A novel no-guide light pen type 3D-coordinate measurement system with three sets of position sensitive devices (PSDs) to realize intersection converge imaging is introduced. It is called as the light pen type measurem...A novel no-guide light pen type 3D-coordinate measurement system with three sets of position sensitive devices (PSDs) to realize intersection converge imaging is introduced. It is called as the light pen type measurement system, because the measuring head is shaped as a pen with several light sources on it. The structure design, measurement principle and experimental results are presented. The theoretical analysis and experimental results prove that this system has advanced features of simple structure, high automation, and high accuracy, and can be used in the measurement fields of mechanical manufacture, robot, auto, aviation and medicine effectively.展开更多
It has been known that the error of measuring acoustic veloicities of thin sediment layers by the well-known T2-X2 approach is usually untolerable, and that this approach is unavailable in the case where sea-bed is ha...It has been known that the error of measuring acoustic veloicities of thin sediment layers by the well-known T2-X2 approach is usually untolerable, and that this approach is unavailable in the case where sea-bed is hard because no echo from any subsurface below sea-bottom can be received. Therefore applying the ray-parameter method to thin layers and the refraction method to hard layers need to be considered in an acoustic velocity measurement system composed of a sound source and a towed hydrophone streamer. Some problems of practical importance about the applications of the two methods, such as echo-data processing procedures and error estimations in measuring acoustic veloicities, are discussed, and the effectiveness of theoretical analyses has been verified through computer simulations.展开更多
The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in...The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in the prediction of wind wave properties.展开更多
An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochem...An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochemical method in aqueous solution using K_4Fc(CN)_6 as supporting electrolyte, and the anions were doped into the film.Ion exchange behaviour of doped Fe(CN)_6^(3-/4-)in the PPY film with Cl^-,NO_3^- or F^- ions in solution has been studied,and the corresponding ion exchange selec- tivity coefficients were determined.展开更多
基金This work wag supported by the National Natural Science Foundation of China.
文摘A microcomputer-based UV/V in situ spectroelectrochemical measurement system has been developed.This paper presents a description of the experimental details regarding the methods and equipment.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11472281 and 11532014)
文摘Accurate aerodynamic measurements in the hypersonic flow of large aircraft models in tunnels have practical significance, but pose a significant challenge. Novel aerodynamic force measurement methods have been proposed,but lack theoretical support. The forms of the force signals techniques for signal processing and calculation of aerodynamics are especially problematic. A theoretical study is conducted to investigate the dynamic properties based on models of the draw-rod system and slender rods. The results indicate that the inertia item can be neglected in the rod governing equation;further, the solutions show that the signals of each rod are a combination of aerodynamic signals(with a constant value) and sine signals, which can be verified by experimental shock tunnel results. Signal processing and aerodynamics calculation techniques are also found to be achievable via the flat part of the signals.
基金This work was supported by the National Natural Science Foundation of China under Grant No. 59875066. X. Zhang's e-mail address is zhangxf@eyou.com.
文摘A novel no-guide light pen type 3D-coordinate measurement system with three sets of position sensitive devices (PSDs) to realize intersection converge imaging is introduced. It is called as the light pen type measurement system, because the measuring head is shaped as a pen with several light sources on it. The structure design, measurement principle and experimental results are presented. The theoretical analysis and experimental results prove that this system has advanced features of simple structure, high automation, and high accuracy, and can be used in the measurement fields of mechanical manufacture, robot, auto, aviation and medicine effectively.
文摘It has been known that the error of measuring acoustic veloicities of thin sediment layers by the well-known T2-X2 approach is usually untolerable, and that this approach is unavailable in the case where sea-bed is hard because no echo from any subsurface below sea-bottom can be received. Therefore applying the ray-parameter method to thin layers and the refraction method to hard layers need to be considered in an acoustic velocity measurement system composed of a sound source and a towed hydrophone streamer. Some problems of practical importance about the applications of the two methods, such as echo-data processing procedures and error estimations in measuring acoustic veloicities, are discussed, and the effectiveness of theoretical analyses has been verified through computer simulations.
文摘The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in the prediction of wind wave properties.
基金This work was financially supported by the National Natural Science Foundation of China.
文摘An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochemical method in aqueous solution using K_4Fc(CN)_6 as supporting electrolyte, and the anions were doped into the film.Ion exchange behaviour of doped Fe(CN)_6^(3-/4-)in the PPY film with Cl^-,NO_3^- or F^- ions in solution has been studied,and the corresponding ion exchange selec- tivity coefficients were determined.