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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Wang K.C. Asbeck P.M. Chang M.F. Sullivan G.J. Miller D.L. Basit H.F. 《Electronics letters》1989,25(17):1111-1112
The authors report a novel noninterfering and simple approach for evaluation of circuits implemented with AlGaAs/GaAs heterojunction bipolar transistors (HBTs). This method makes use of radiative recombination in the base region of current-carrying HBTs. The infrared radiation emitted is 'visible' to the closed-circuit TV (CCTV) cameras. Therefore, one can view the operation of the HBT circuit under test at normal biases with a TV monitor. This method can be used to determine logic states of gates, as well as collector current of individual HBTs within integrated circuits.<> 相似文献
992.
993.
Estrogenic personal care products in a greywater reuse system. 总被引:1,自引:0,他引:1
H R Andersen M Lundsbye H V Wedel E Eriksson A Ledin 《Water science and technology》2007,56(12):45-49
The occurrence and fate of parabens in a greywater system was assessed. The potential for removal of residual paraben concentrations in effluent greywater with chlorine dioxide was also investigated. The influent to the greywater plant was characterised by considerable variation, with concentrations from below the detection limit to 40 microg/L and the five commonly used parabens in consumer products were frequently detected. After the biological treatment only two paraben were detected with concentration from 65-120 ng/L. Chlorine dioxide treatment of the biologically treated effluent with dosages down to 0.75 mg/L resulted in more than 97% reduction of all parabens. Formation of the by-product chloroform was insignificant from the chlorine dioxide treatment. 相似文献
994.
The objective of this research is to investigate the feasibility of a theoretical development which could lead to advanced manipulator concepts offering fast dynamic and control features. Specifically, the application of “dynamic linearization” to a kinematically redundant planar manipulator is studied. In comparing such a manipulator with a standard non-linear, non-redundant design it is shown that in addition to the expected merits in linearity, dexterity, and computational simplicity, savings in actuator energy consumption can also be realized using a relative simple trajectory optimization scheme. 相似文献
995.
The scattering absorption and profile losses of PCVD fibres are analysed. The Rayleigh scattering increases proportionally to the sum of the F- and Ge-dopant concentrations, the UV absorption is proportional to the Ge concentration, and profiling losses are negligible.<> 相似文献
996.
997.
Yu. I. Kadashevich 《Strength of Materials》1991,23(5):552-555
The significance of the concepts of thermodynamic time and microstress tensor introduced by A. A. Vakulenko for development of the theory of viscoplasticity is analyzed.Translated from Problemy Prochnosti, No. 5, pp. 56–58, May, 1991. 相似文献
998.
999.
V. A. Tsykanov A. A. Maershin A. A. Petukhov O. V. Skiba P. T. Porodnov G. I. Gadzhiev I. S. Golubenko E. P. Klochkov A. A. Teikovtsev V. K. Shamardin 《Atomic Energy》1989,66(5):329-333
Translated from Atomnaya Énergiya, Vol. 66, No. 5, pp. 299–302, May 1989. 相似文献
1000.