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	Influence of asymmetrical stator axes on the electromagnetic field and driving characteristics of canned induction motor 期刊论文 OAI收割 IET ELECTRIC POWER APPLICATIONS, 2019, 卷号: 13, 期号: 8, 页码: 1229-1239 作者: An Yuejun; Zhang Zhiheng; Li Ming; Wang Guangyu; Kong Xiangling \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2021/02/02 electric potential harmonic distortion stators finite element analysis induction motor drives machine control electromagnetic fields magnetic flux air gaps asymmetrical stator axes electromagnetic field driving characteristics canned induction motor high vacuum application asymmetrical stator phase healthy condition ASA conditions back-electromotive force winding theorem CIM control system finite-element models total harmonic distortion air-gap flux density stator current power 1 9 kW
	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	Design of high-resolution fourier transform lens (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 With the development of optical information processing high-resolution Fourier transform lens has often been used in holographic data storage system spatial filtering and observation of particles. This paper studies the optical design method of high-resolution Fourier transform optical lenses system which could be used in particles observation and holographic data storage system. According to Fourier transform relation between object and its frequency plane and the theory of geometrical optics the system with working wavelength 532nm and resolution 3 m was designed based on ZEMAX. A multi-configuration method was adopted to optimize the system's lenses. In the optical system a diaphragm was placed at the system's spectrum plane and the system demanded a low vacuum to cut down the influences of atmosphere and other particles. The result of finite element analysis indicated that the influences of vacuum pumping to optics spacing and mirror surface shape very minor and the imaging quality not being affected. This system has many advantages such as simple structure good image quality and a high resolution of 3 m. So it has a wide application prospect and can be used both in holographic data storage system and particles observation.
	Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文 OAI收割 Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom 作者: Liu L.; Liu L.; Wang W.; Wang W. 收藏 \| 浏览/下载：46/0 \| 提交时间：2013/03/25 Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material such as a high aspect ratio and sharp tip high chemical stability high mechanical strength stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2 and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM) as shown in fig.1(a b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another when the electric field between anode and cathode is 10V/ m the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material and the carbon microtubes have better field emission properties. 2005 IEEE.