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131.
Nishizuka N. Nakatsuyama M. Nagahashi H. Sasaki T. Sato R. 《IEEE transactions on magnetics》1989,25(5):3260-3262
The pulse responses of magnetically coupled pulse transformers of arbitrary turn ratio n :1 are considered in the framework of a distributed parameter theory. Equivalent circuits for the calculation of pulse risetime and flat-top responses are introduced for inverting- and noninverting-type transformers, respectively. With these equivalent circuits, the pulse risetime responses are calculated more precisely than with the lumped-parameter circuit theory. Measured responses of pulse transformers agree well with the theoretical predictions 相似文献
132.
The effects of molybdenum, phosphorus and of microstructure on creep were studied at 550°C utilizing the model alloys Fe—3 Cr—0.05P, Fe—3 Cr—1 Mo—0.05P and Fe—3 Cr—1 Mo. The heat treatments were varied to obtain a ferritic or bainitic structure, the effect of a preheat treatment of 300 h at 550°C was investigated. Both Mo and P increase the creep strength by different mechanisms which lead to four types of creep curves, with 1 to 3 minima. The results are discussed using microstructural information from transmission electron-microscopy. 相似文献
133.
This paper presents a novel parallel processing system for image synthesis using ray tracing. An object space is divided into parts (subspaces), each of which is allocated to a processor. The processor detects, simultaneously the intersections of the surfaces of each object and a fixed number of rays over the whole space, and calculates the local intensity on an object in each subspace. The global intensities of pixels on a screen are calculated by the other kind of processors simultaneously. We also present the optimal data structure, based on an adaptive division algorithm, for parallel processing of the object space. 相似文献
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The tetragonal-to-monoclinic phase transformation of yttria partially stabilized zirconia by low temperature annealing in air was investigated in the temperature range 100 to 650° C using a sintered body of zirconia containing 2 to 4 mol% Y2O3. The amount of monoclinic phase formed was maximum at about 200° C. Both the decrease in grain size and increase in the yttria concentration were effective in decreasing the critical temperature below which the monoclinic phase was formed. The relationship between the critical temperature (T c) and the grain size was experimentally determined. 相似文献
136.
Intracarotid injection of a low dosage of amobarbital (75 mg, 5% solution) was studied in 30 temporal lobectomy candidates while naming achromatic, incongruously, and congruously colored pictorial objects and reading real, nonsense, and embedded words. Semantic errors and phonological alexia followed the left injection, while the right injection induced visuoperceptual errors. When the contralateral hemisphere was anesthetized, the left brain formulated supraordinate categories for words and objects, while the right brain applied concrete labels. The basic language proficiency of patients influenced recovery and outcome; left temporal patients who were interictally anomic performed especially poorly after both injections. Codifying phonological and perceptual changes during the intracarotid amobarbital procedure can improve interpretations about language laterality and organization. 相似文献
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Degradation mechanism of H2 permselectivity under atmosphere of steam/N2 = 3 at 773 K was investigated among amorphous silica membranes on γ-Al2O3-coated α-Al2O3 or Ni-doped γ-Al2O3-coated α-Al2O3 synthesized by counter diffusion chemical vapor deposition. Helium and H2 permeance drastically decreased during the first few hours of hydrothermal exposure. On the other hand, N2 permeance fluctuated during hydrothermal treatment in silica membrane on γ-Al2O3-coated α-Al2O3. The degree of N2 permeance change depended on the hydrothermal stability of the intermediate layer. Hydrogen permselectivity was affected by both the densification of amorphous silica and the sintering of the intermediate layer during hydrothermal exposure. 相似文献