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111.
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A. M. Pristrem N. I. Danilovich V. A. Labunov 《Journal of Engineering Physics and Thermophysics》1987,53(6):1464-1472
By using integral transform methods, an approach is developed to the solution of a problem on the temprature distribution in multilayer structures heated by cw scanning laser radiation, with phase transitions in the layers taken into account.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 6, pp. 1000–1010, December, 1987. 相似文献
114.
Mostafa A. G. Sanad A. M. Kashif I. El-Saghier A. A. 《Journal of Materials Science Letters》1985,4(5):571-574
Journal of Materials Science Letters - 相似文献
115.
Oliveira M. Dart-Mao Cheung C. Al-Zayed A. Chio I.-F.F. Swisher R.R. Lecuyer F. DeLisio M.P. 《Antennas and Propagation, IEEE Transactions on》2002,50(5):698-702
Grid-mixer arrays can achieve high linearity and dynamic range through quasi-optical power combining. We present a 100-element single-ended diode grid mixer operating at 2.45 GHz. Each element incorporates two diodes in series. We measure an input third-order intercept of 11 W (40.5 dBm), and output third-order intercept of 3.4 W (35.4 dBm), and an associated conversion loss of 5.1 dB. The power-handling capability of the array is 100 times larger than that of a microstrip mixer using a single element. The local oscillator (LO) drive requirement for the entire array is 1.4 W (31.6 dBm). The angular dependence of the array's IF power is also presented and is in agreement with theory 相似文献
116.
117.
This report deals with direct observations of microcrack linkage at the crack tip prior to macroscopic crack initiation. It is shown that this process is directly linked to the inclusion distribution in the material and can be considered in terms of an R curve to describe microcrack development. 相似文献
118.
On the basis of the experimental data, we show that the difference between the macroscopic and microscopic fatigue crack growth rates in the second section of the kinetic diagram of fatigue fracture is caused by the effect of crack closure within the limits of its existence. We establish the relationships between the macroscopic and microscopic fatigue crack growth rates and the structure of the material in the second section of the diagram for various values of the load ratio with regard for the effect of crack closure and propose a procedure of examination of the fracture processes in structural materials based on the analysis of microscopic and macroscopic fatigue crack growth rates. 相似文献
119.
Incremental transmission loss analysis has been used for decades, but recent interest in its application to loss allocation calls for new in-depth results. This paper demonstrates that, for incremental methods to be applied correctly in loss allocation, it is first necessary to specify the load distribution and loss supply strategies. Incremental loss allocation among bus power injections is shown to be arbitrary and, therefore, open to challenge as discriminatory. Loss allocation is possible among incremental loads and/or generators, but the proportion of the total losses assigned to either one is arbitrary. Unique, nonarbitrary incremental loss allocations are however possible among the "equivalent" incremental bilateral exchanges between generators and loads. From these basic components it is possible then to calculate the allocation among generators or loads in any specified proportion. The main results, although developed initially for small increments, are extended to large variations. Finally, a general incremental loss allocation algorithm is developed and tested 相似文献
120.
Androstenedione labeled with tritium at positions 1 and 2 was prepared. The molar radioactivity of the sample prepared using homogeneous catalysts was as high as 1.4-1.5 PBq mol-
1. [1,2-3H]Androst-4-ene-3,17-dione can be converted into the [1-3H]steroid with the molar radioactivity of 0.9 PBq mol-
1. 相似文献