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1.
The Monte Carlo method is used to simulate video signals from a scanning electron microscope in backscattered electrons from slit-like structures with a rectangular profile and widths of 0.1, 0.5, and 4.0 m.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 22–23, August, 1995.  相似文献   
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The aim of this study was to identify conditions under which the presence of tall strike object can serve to increase or decrease lightning-induced voltages on a nearby overhead wire. We examined the ratios of magnitudes of lightning-induced voltages on the overhead wire for the cases of strikes to a tall object and to flat ground as a function of distance from the lightning channel d, current reflection coefficients at the top of the strike object /spl rho//sub top/ and at the bottom of the strike object /spl rho//sub bot/, the current reflection coefficient at the channel base (in the case of strikes to flat ground) /spl rho//sub gr/, and the return stroke speed v. Lightning-induced voltages were computed using the finite-difference time-domain (FDTD) method. The transmission line (TL) model was used to find the distribution of current along the lightning channel and the strike object. The ratio of magnitudes of lightning-induced voltages for tall-object and flat-ground cases increases with increasing d (ranging from 40--200 m), decreasing /spl rho//sub bot/(<1), decreasing /spl rho//sub top/ (<0, except for the case of /spl rho//sub bot/=0), and decreasing v (相似文献   
3.
Data are given on the test object for scanning electron microscopy in which the components (ridges) are of trapezoidal profile and have large angles of inclination for the side walls. The width of the top surface of a projection is less than 10 nm. Methods have been developed for measuring such dimensions of test objects on standard scanning electron microscopes. __________ Translated from Izmeritel'naya Tekhnika, No. 8, pp. 20–23, August, 2008.  相似文献   
4.
We present a comparison of data obtained during testing of lightning protective system of a residential structure in rocket-triggered lightning experiment at the International Center for Lightning Research and Testing(ICLRT)at Camp Blanding,Florida,and current surge generator experiment at Rzeszow University of Technology in Poland.Three different configurations of LPS were tested in Poland with the dc grounding resistances of the entire system 4.09 Ω(LPS 1a),1.65 Ω(LPS 1b),and 2.88 Ω(LPS 2).For LPS 1a with three ground rods the value of the peak current entering the electrical circuit neutral was about 56% of the injected current peak,and for LPS 1b with two additional ground rods and two 5 m long buried horizontal conductors it was about 16%.For LPS 2 with five ground rods interconnected by a buried loop conductor this ratio was 21%.The current waveshapes in the ground rods differed from the injected current waveshapes and the current waveshapes in other parts of the test system,especially,for poorer-grounding LPS 1a.The surge-generator results are consistent with those of triggered-lightning experiments at Camp Blanding,Florida(DeCarlo et al.,2008 [2]).  相似文献   
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X-ray diffraction analysis, transmission and scanning electron microscopy, and electron microprobe analysis were used to study Bi,Pb-2223/Ag composites annealed in a low-oxygen atmosphere (7.5% O2 + 92.5% N2). The ceramics was found to be characterized by some nonuniformity in the distribution of all the components. Two structural peculiarities of the 2223 phase were found. These are the existence of atomic displacement waves, which are related to the oxygen deficiency or nitrogen substitution for oxygen, and a more intense Ag penetration into the ceramics, which results from the annealing in the O2-N2 atmosphere at a pressure of 10 atm. The unstable state of the lattice characterized by oxygen atomic displacement waves is due to the prolonged annealing in oxygen-depleted atmosphere. Usually, in the case of other favorable factors of the ceramics structure, the lattice instability positively affects the superconducting properties of the ceramics.  相似文献   
7.
Measurements of the line width of one and the same test object under high- and low-voltage scanning electron microscopes are performed. Translated from Izmeritel’naya Tekhnika, No. 1, pp. 15–17, January, 2009.  相似文献   
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A periodic linear measure is described for use in scanning electron microscopes, which has eight values for line width in the micrometer and submicrometer ranges. Methods have been developed for calibrating the SEM with such a measure, which are not sensitive to errors in beam focusing. Translated from Izmeritel'naya Tekhnika, No. 4, pp. 48–52, April, 2000.  相似文献   
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