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781.
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783.
H.G.C. Human N.P. Ferreira C.J. Rademeyer P.K. Faure 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(7):593-602
A method and computer program were developed for calculating the temperature of any part of a graphite furnace tube at any instant of time after onset of the heating cycle. Results for tubes of the Massman design show large differences in spatial temperature distributions during and at the end of the heating cycle when equilibrium is reached. When constant current is applied to contoured tubes, greater heating rates at the tube centres are obtained than with standard tubes. 相似文献
784.
M. V. Davidovich 《Radiophysics and Quantum Electronics》2006,49(3):210-219
We propose a method which transforms homogeneous integral equations into inhomogeneous ones for problems of diffraction by
semi-infinite structures. New integral equations and the corresponding stationary functionals dependent on the desired scattering
parameters are obtained. The consideration is performed for the open-end diffraction problem of a parallel-plate waveguide
which has a rigorous solution, but the method has sufficient generality to use it for two-dimensional surface integral equations
describing planar and nonplanar structures as well as for an arbitrary structure of waveguide transformer type, the solution
for which can be sought in the finite domain. The method is based on field representation at the infinity as incident and
scattered waves.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 3, pp. 235–245, March 2006. 相似文献
785.
786.
787.
788.
A method for estimating the systematic uncertainty associated with radon in the SAGE experiment1) aimed at observing the solar-neutrino flux is described. For the gallium target used in this experiment, the systematic uncertainty in the measured neutrino-capture rate of 75 SNU2) is below 0.3 SNU. 相似文献
789.
Ivonin I. V. Lavrent'eva L. G. Aleksandrova G. A. Devyat'yarova L. L. 《Russian Physics Journal》2002,45(10):997-1000
The effect of the arsenic concentration in the vapor phase on the growth step distribution over the surface of GaAs epitaxial layers grown in a chlorine-hydride vapor-transport system on substrates with 4° (111)A and (113)A orientations is studied. It is demonstrated that the average distance between steps in the echelon depends on the arsenic concentration and increases with it up to a certain constant value. It is assumed that this is connected with the change in the kink density at the steps. 相似文献
790.
N. V. Studenichnik 《Acoustical Physics》2002,48(5):598-606
Experimental data are presented on the fine structure of the sound field in an underwater sound channel for low and infralow sound frequencies. The experiments are performed in the Black Sea, on a 600-km-long path, with explosive sound sources. The intensity, space-time, and frequency characteristics of the sound field are analyzed. The geometric dispersion of the first normal wave is experimentally studied. The role of the channel inhomogeneities in the violation of the sound field coherence is determined for different frequency bands. On the basis of the experimental data, the vertical distribution of the critical frequencies of the waveguide is obtained, and the validity limits are established for the wave and ray calculation methods. The applicability of the phase methods for calculating the sound fields in waveguides with dispersion is discussed. The frequency-angular dependence of the effective sound attenuation coefficient in an underwater waveguide is revealed and explained. 相似文献