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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A study is made of the electric fields and currents induced in the organs of the human body when exposed to high-voltage 50-60-Hz transmission lines and 10-30-kHz high-power transmitters. Relevant analyses previously carried out are summarized and supplemented with detailed investigations that complete the picture. Incomplete, misleading, and incorrect statements and methods in the related literature are pointed out, completed, and corrected. The major contribution is to provide quantitatively accurate, relatively simple analytic formulas that relate the incident electric field to the induced field in the organs of the body. The formulation and solution of the underlying integral equation are carried out in an Appendix 相似文献
992.
Pallares J. Marsal L.F. Correig X. Calderer J. Alcubilla R. 《Electron Devices, IEEE Transactions on》1998,45(1):54-61
This paper addresses the problem of the space charge region Shockley-Read-Hall (SRH) recombination currents in heterojunctions with one noncrystalline side. A formulation which generalizes previous works is discussed. The approach is based on the drift-diffusion model with a thermionic-field emission boundary condition. The main physical parameters which determine the relative contribution of each zone of the space charge region (SCR) to the total recombination current are identified. The general analysis is applied for the first time to amorphous/crystalline heterojunctions and design criteria are established to minimize the total recombination current 相似文献
993.
Gunapala S.D. Bundara S.V. Liu J.K. Winn Hong Mani Sundaram Maker P.D. Muller R.E. Shott C.A. Carralejo R. 《Electron Devices, IEEE Transactions on》1998,45(9):1890-1895
A 9-μm cutoff 640×486 snap-shot quantum well infrared photodetector (QWIP) camera has been demonstrated. The performance of this QWIP camera is reported including indoor and outdoor imaging. The noise equivalent differential temperature (NEΔT) of 36 mK has been achieved at 300 K background with f/2 optics. This is in good agreement with expected focal plane array sensitivity due to the practical limitations on charge handling capacity of the multiplexer, read noise, bias voltage, and operating temperature 相似文献
994.
R. L. Dotson 《Journal of Applied Electrochemistry》1993,23(9):897-904
Perchloric acid, HCLO4, and ammonium perchlorate, NH4ClO4, of high purity have been produced by electrolysis of chloric acid and subsequent reaction with high purity ammonium hydroxide
to produce ammonium perchlorate. The process involves no alkali metals, chlorides or transition metals such as chromates,
and thus produces propellant and explosive grade ammonium perchlorate of high purity and with no associated instability or
pollution problems. The products can be recovered by solution crystallization-drying or direct spray-drying, respectively. 相似文献
995.
Control of volatile organic compounds by an AC energizedferroelectric pellet reactor and a pulsed corona reactor 总被引:1,自引:0,他引:1
Yamamoto T. Ramanathan K. Lawless P.A. Ensor D.S. Newsome J.R. Plaks N. Ramsey G.H. 《Industry Applications, IEEE Transactions on》1992,28(3):528-534
Two laboratory-scale plasma reactors, an alternating current (AC) energized ferroelectric (high dielectric ceramic) packed bed reactor and a nanosecond pulsed corona reactor, were constructed. This study was done to develop baseline engineering data to demonstrate the feasibility of the application of plasma reactors to the destruction of various volatile organic compounds (VOCs) at PPM levels. Complete destruction was obtained for toluene. Conversions of methylene chloride at 95% and trichlorotrifluoroethane (known as CFC-113) at 67% were achieved for the plasma reactors used. The conversion was dependent on the mean electron energy in the reactor and was also related to how strongly halogen species were bonded with carbon 相似文献
996.
997.
D.L Orphal C.E Anderson Jr. R.R Franzen J.D Walker P.N Schneidewind M.E Majerus 《International Journal of Impact Engineering》1993,14(1-4):551-560
Calculations of steel target penetration by L/D ≤ 1 tungsten and tungsten alloy projectiles have been extended to L/D = 1/32 over the velocity range 1.5 to 5 km/s. The ratio of crater to projectile diameter tends to 1 as L/D decreases over this entire velocity range. For impact velocities of 1.5 and 3 km/s, penetration depth normalized by projectile length, P/L, increases with decreasing projectile L/D up to a maximum value and then decreases for still lower L/D. Experiments at impact velocities of 2 and 3 km/s confirm these results. For 5 km/s impact velocity, the calculations show P/L increasing with decreasing projectile L/D over the entire range 1/32 ≤ L/D ≤ 1. The projectile L/D for which the maximum P/L occurs appears to depend on the impact velocity. P/L generally scales with impact velocity as P/L vf(L/D) where f(L/D) ranges from 0 for a long rod to, we believe, 2 in the limit as projectile L/D approaches zero. The calculations show for 1/8 ≤ L/D ≤ 1/2, P/L v0.9; for L/D = 1/16, P/L v1.5; and for L/D = 1/32, the new results give P/L v1.9. 相似文献
998.
999.
1000.
This paper presents a selection of results of a comprehensive quantitative, research literature-based study of Dutch energy research. The primary goal of this paper is to provide an overview of what bibliometric data from ISI and non-ISI databases may offer to describe the state of affairs in a scientific field. It illustrates the added value of combining bibliometric indicators of publication output, international visibility, international co-operation, and interdisciplinarity in a study of nuclear energy research in the 1980's when its budget decreased dramatically. 相似文献