共查询到20条相似文献,搜索用时 453 毫秒
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《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1991,19(6):1003-1012
High-pressure mercury lamps, metal halide arc lamps, high-pressure sodium lamps, xenon short-arc lamps, xenon flashlamps, and microwave-excited metal halide lamps are extremely important commercial applications of LTE and near-LTE plasma physics. The author outlines in very brief form the basic plasma science in such light sources. The factors controlling the power balance and the luminous efficacy of such sources are discussed. Current research in modeling these complex plasma devices is described. This has reached the stage that successful CAD models are available for new-product design in mercury and high-pressure sodium lamps, but not yet for metal halide lamps. The behavior of electrodes is discussed as an important practical determinant of lamp life. Directions of future research and development are briefly discussed 相似文献
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介绍了光学电流测量技术的发展情况,描述了目前几种主要的互感器结构及其基本原理,并对各自存在的问题及解决途径进行了讨论。从研究现状来看,块状玻璃型传感器技术相对成熟,已经有商业产品问世;混合型传感器测量精度较高,但传感头有源电路的供电技术复杂,还没有圆满的解决方案;全光纤型是光学电流互感器发展的最终目标,目前存在的主要问题是光纤的固有线性双折射难以处理,有赖于新型光纤材料及集成光学元件的进一步发展。最后综合评述了光学电流互感器技术的发展趋势及产业化前景。 相似文献
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S. Gozzini E. Mariotti C. Gabbanini A. Lucchesini C. Marinelli L. Moi 《Applied physics. B, Lasers and optics》1992,54(5):428-433
The performances of white light cooling are shortly reviewed and discussed. The velocity distributions modified by the cooling laser are calculated under different boundary conditions and a new experimental approach, which permits to obtain a sharp edge laser bandwidth, is taken into consideration. Finally, the preliminary experimental results on a sodium beam cooled by a lamp laser are reported. 相似文献
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S. D. Baker W. I. Milne P. A. Robertson 《Applied Physics A: Materials Science & Processing》1988,46(4):243-248
This paper reviews the production of silicon oxide thin films using a novel photoenhanced deposition technique incorporating a windowless nitrogen discharge lamp contained within the deposition vessel. This process has the potential to produce better semiconductor/insulator interfaces than those produced using conventional RF glow discharge techniques, since there is no damage to the growing film surface from energetic ions produced in the glow discharge plasma. The use of an internal lamp obviates the need for a window between the lamp and reaction chamber and thus overcomes the problems of attenuation of short wavelength ultraviolet radiation by the window. All the ultraviolet output of the lamp can now directly couple into the reaction gases, so the need for sensitising agents is also removed. Thin films of silicon oxide have been deposited onto single crystal silicon wafers from nitrous oxide-silane gas mixtures. The physical properties are comparable to those of high quality insulator films deposited by plasma enhanced techniques. The results of electrical measurements indicate that this material is of sufficiently high quality to be used as a low temperature deposited gate dielectric for thin film devices. To confirm this, thin film transistors (TFTs) have been fabricated using the material (and an active layer of amorphous silicon deposited in the same system) and characteristics of these TFTs are also presented. 相似文献
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Ҧΰ־������������ �����³������� �� 《核聚变与等离子体物理》2020,39(4):362-372
The interactions between charged particles and wall materials produce dusts in plasma devices. Progress of dust research on the main plasma devices are reviewed, the approaches to measure dusts and the results obtained in main plasma devices in the world are presented. The unsolved problems and possible directions for further advancements are commented. 相似文献
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等离子体装置中,带电粒子与壁材料相互作用会导致粉尘的产生。综述了主要等离子体装置中粉尘问题的实验研究现状,对主要装置中使用的诊断方法和所得到的实验结果进行了评述。提出了等离子体装置粉尘研究中存在的问题以及未来研究的方向。 相似文献
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为了研究不同黄疸治疗仪光源的发光光谱对新生儿产生紫外辐射、热辐射等潜在的光生物安全问题,本文利用光辐射安全测定系统OST-300对传统蓝光荧光灯、普通蓝光LED灯以及经简单遗传算法计算与拟合的蓝光LED灯进行了测试与对比分析。实验结果表明:传统蓝光荧光灯在315,330,365 nm的紫外光处有明显的波峰出现,且峰值波长在365 nm处较为明显;传统蓝光荧光灯在老化后其蓝光光谱光衰严重,且存在大量的红外光线;而基于简单遗传算法计算与拟合的蓝光LED发光光谱与体内胆红素的吸收光谱相吻合,能避免对新生儿的光辐射危害。因此,本文提出的蓝光LED是治疗新生儿黄疸的理想光源。 相似文献
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《应用光谱学评论》2013,48(4):475-507
Abstract The application of metal (tantalum, molybdenum, and platinum) devices in analytical atomic spectrometry is reviewed in this article. These metal devices have been employed in various analytical atomic spectrometric techniques for more than three decades, mainly as electrothermal atomizers or electrothermal vaporizers, in various physical shapes, such as tubes, platforms, loops, and wires (or coils/filaments). Their application spans from atomic absorption spectrometry (AAS), atomic emission spectrometry (AES) atomic fluorescence spectrometry (AFS), inductively coupled plasma atomic emission spectrometry (ICP‐AES) to inductively coupled plasma mass spectrometry (ICP‐MS). The analytical figures of merit and the practical applications reported for these metal devices are reviewed, and the atomization mechanism on these metal atomizers is briefly summarized, too. In addition, other applications of the metal devices are discussed, including analyte preconcentration by electrodeposition and sequential metal vapor elution analysis (SMVEA). Furthermore, the application of these metals in graphite furnaces encompasses the schemes with the metals in the form of furnace linings, platforms, or impregnated salts. 相似文献
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Michael Jaffe 《Journal of statistical physics》1991,62(5-6):985-995
The science and technology of liquid crystal polymers is selectively reviewed with an emphasis on those aspects key to successful commercial utility. The importance of the low viscosity demonstrated by nematic polymers under commercial processing conditions, coupled with the low volume change on cooling and high thermal stability associated with these nematogens, is identified as the major factor behind the success of the thermotropic copolyester as a high-performance molding resin. The developing area of side-chain liquid crystal polymers as electro-optical media is discussed, stressing the importance of combining function and processibility for ultimate commercial viability. Potential markets and projected commercial growth rates are discussed from the point of view of the enabling science needed to successfully define and implement new commercial applications for liquid crystal polymers. 相似文献
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Zavjalov M.A. Mitin L.A. Perevodchicov V.I. Tskhai V.N. Shapiro A.L. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1994,22(5):600-607
A powerful beam-plasma amplifier operating under continuous conditions is described. The amplifier is designed on new principles using hybrid plasma-cavity electrodynamic structures. The theory and foundation for calculating slow-wave structures having a plasma filled propagation channel, and the interaction of an electron beam with a hybrid plasma-cavity system, are considered. Considerably increased power of microwave radiation and expansion of the operating pass-band is shown to result when the propagation channel is filled with plasma. The use of new principles makes it possible to create an amplifier with an efficiency and 3 dB operating band width higher than those attained in vacuum devices 相似文献
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A. M. Valshin S. M. Pershin G. M. Mikheev 《Bulletin of the Lebedev Physics Institute》2017,44(8):228-231
It is experimentally justified for the first time that electrodeless induction pump of plasma of standard cylindrical luminescent lamps provides optimization of the high-frequency inductive–capacitive (HFI) discharge conditions. The acceptable frequency range and the effect of the capacitance between the inductor and plasma on the efficiency of resonant energy injection into discharge plasma are revealed. An increase in the luminous efficiency to 25% in the range of pump powers multiple of the lowest nominal power for the lamp under standard operating conditions is detected. Physics of the found phenomenon and the range of application of the power saving technology for electrodeless pumping of luminescent lamps with increased operation life are discussed. 相似文献
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The use of the optogalvanic effect (OGE) in a hollow cathode lamp for wavelength tuning of dye lasers is an established technique at laser wavelengths longer than 560 nm, corresponding to photon energies less than 2.2 eV. This work describes the first successful optogalvanic studies on caesium at higher photon energies. Once set up, OGE in a standard commercial hollow cathode lamp provides a quick and cheap means of tuning a continuously tunable laser to a chosen atomic transition. The
lines in caesium at 455.55 nm and 459.32 nm were resolved. This work is also believed to be the first to describe the detection of any caesium transition using the optogalvanic effect in a commercial hollow cathode lamp, rather than a specially constructed tube. The method used is applicable to other materials which have previously proved difficult. 相似文献
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Professor Stig Stenholm 《Contemporary Physics》2013,54(3):279-280
Current activity in the field of magnetic separation is reviewed in fundamental terms. The diverse subject matter is ordered into four main groupings whose characteristics are described in terms of numerous devices, both of present-day and historical significance. Existing as well as potential areas of scientific and commercial operation are discussed. The basic principles of recent major developments in high intensity magnetic Separation are closely examined. 相似文献
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Uo K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1988,16(4):401-415
A brief history of the heliotron, one of the promising candidates for a commercial fusion reactor, is given. The heliotron device can be operated in steady state, since it has a stable magnetic field with high rotational transform and high shear and without ohmic current in the plasma. The results of experimental and theoretical studies on heliotron devices are reported, and future prospects are given 相似文献