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101.
A. D. Bulanov A. N. Moiseev O. Yu. Troshin V. V. Balabanov D. V. Isaev 《Inorganic Materials》2004,40(6):555-557
High-purity isotopically enriched (99.98% 28Si, 99.57% 29Si, and 99.83% 30Si) silane samples are prepared for the first time. The total hydrocarbon content of the samples is no higher than 0.1–0.3 ppm. The concentration of electroactive impurities in the silicon prepared from the purified monoisotopic silane is below 1015 cm–3. 相似文献
102.
I. A. Grishin V. A. Gur'ev E. B. Intyushin Yu. E. Elliev A. P. Savikin 《Inorganic Materials》2004,40(4):431-433
TeO2–WO3 glasses coactivated with Er3+ and Yb3+ are prepared. The effect of Yb content on the efficiency of Er photoluminescence (PL) in the visible and IR spectral regions is studied. The highest PL efficiency is achieved at an Er : Yb atomic ratio of 1 : 1. The PL lifetime for the Er3+
4
I
13/2 level is determined to be 7–9 ms. 相似文献
103.
V. N. Perevezentsev M. Yu. Shcherban’ M. Yu. Murashkin R. Z. Valiev 《Technical Physics Letters》2007,33(8):648-650
The structure and mechanical properties of nanocrystalline aluminum alloy 1570 obtained by means of severe plastic deformation have been studied. Being tested in a temperature range from 300 to 400°C, the alloy exhibits high-strain-rate superplasticity. At 400°C, the superplasticity is manifested in a very broad range of strain rates, extending from 5 × 10?3 to 1 s?1. 相似文献
104.
Broadband chaotic oscillations were monitored in a depressed potential collector of a traveling-wave oscillator (TWO). This signal appears due to the oscillations of a virtual cathode, which is formed in the spent electron beam under the action of retarding fields existing in the multistage depressed collector. 相似文献
105.
V. V. Mamutin O. V. Bondarenko A. P. Vasil’ev A. G. Gladyshev A. Yu. Egorov N. V. Kryzhanovskaya V. S. Mikhrin V. M. Ustinov 《Technical Physics Letters》2007,33(5):384-387
The optical properties of heterostructures comprising InAs/InGaAsN quantum wells in strain-compensated GaAsN/InGaAsN superlattices have been studied. It is demonstrated that, using such superlattices of various design and thickness and with additional InAs monolayer spacers, it is possible to control the wavelength of room-temperature emission from InGaAsN quantum wells within 1.3–1.6 μm without deteriorating the output radiation characteristics, which opens additional prospects for the development of lasers on GaAs substrates for telecommunication applications. 相似文献
106.
V. Yu. Karpov 《Materials Science》2007,43(5):746-749
We developed a new type of porous materials with anisotropic structure based on a large number of metals. It is shown that
these material, called gasars, have properties different from the properties of the other porous materials. Thus, the strength
of gasars is much higher than the strength of powder materials with the same porosity and their impact toughness is readily
regulated by the sizes of the pores. The internal structures of gasars and possible versions of the types of pores in these
materials are strongly diversified, which makes the spectrum of their possible applications very wide. We discuss some specific
directions of the potential applications of gasars. The results of measurements of the thermal conductivity of gasars and
monolithic specimens are presented. It is shown that, for a certain level of porosity, the specific thermal conductivity of
gasars is higher than for monolithic materials. We also make some basic conclusions concerning the characteristics of new
porous materials.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 125–127, September–October, 2007. 相似文献
107.
108.
Yu. A. Brodskii V. I. Bazikov I. V. Zubkov A. I. Krylov V. D. Stepanenko 《Chemical and Petroleum Engineering》2006,42(9-10):552-559
Modern designs are examined, and technical data presented for vibratory electric and convection driers, driers with infra-red sources, and steam driers. 相似文献
109.
随着国家对多家办电、混合式经济模式的鼓励和政策优惠,中小水电开发已掀起一股热潮,究其开发模式主要有国有全资、民营独资、股份制等几种。本文主要结合贵州乌江清水河水电开发有限公司对清水河中型水电开发的实际,探究股份制混合经济的投资控制及管理模式。 相似文献
110.