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51.
少数载流子寿命是长波红外HgCdTe材料的重要性能参数。从大量实际数据统计中发现长波红外n型HgCdTe材料的液氮温度电阻和室温电阻的比值与材料载流子寿命有定关系,电阻比值在2 ̄6之间有较大的载流子寿命值,而电阻比值大于10的寿命值较小。 相似文献
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53.
LIU Dacheng CAO Chunan WANG Fuhui LOU Hanyi ZHA NG Lixin Institute of Corrosion Protection of Metals Academia Sinica Shenyang ChinaOriginally published in ACTA METALL SIN 《金属学报(英文版)》1989,2(8):143-145
The resistances against localized corrosion of 1Cr18Ni9Ti microcrystals with normal grainsize and bcc structure obtained hy magnetron sputtering have been compared.The two kindsof microcrystals with (110) and (211) textures respectively were obtained under differentsputtering conditions.Both microcrystals were found to have better resistance against local-ized corrosion than the crystal with normal grain.The microcrystal with (110) preferredorientation has larger resistance to localized corrosion than that with (211) preferredorientation. 相似文献
54.
E. G. Il’in A. S. Parshakov A. Yu. Teterin K. I. Maslakov Yu. A. Teterin 《Inorganic Materials》2011,47(4):442-448
The surface of a MoCl2C30H30 composite in the form of molybdenum nanoclusters in a polyacetylene matrix, produced by reacting MoCl5 with C2H2 in benzene and toluene, has been studied by X-ray photoelectron spectroscopy before and after Ar+ ion milling. The composite actively reacts with atmospheric oxygen and moisture. As a result, the molybdenum clusters on its surface oxidize to molybdenum(V) or molybdenum(VI) oxides or oxychlorides (E b(Mo 3d 5/2) = 232.3–232.5 eV) during the sample preparation process. The electron binding energy of molybdenum affter surface etching (E b(Mo 3d 5/2) = 228.5 eV) suggests that the oxidation state of the molybdenum in the composite is 2+ or 3+. Analysis of the structure of the spectrum of the C 2s electrons of the inner valence molecular orbitals using the energy level diagram of the C2 molecule suggests that the hydrocarbon matrix of the composite contains, in addition to-CH=CH-CH=CH- conjugate bonds, linear carbyne fragments: -HC=C=CH- or -C≡C-. After etching, the surface layer of the composite contained argon, which might be due to adsorption because of the small particle size of the composite or chemisorption on the surface of the polyacetylene matrix. The composite is stable in a high vacuum of 1.3 × 10−5 Pa up to 350°C and does not experience charging when exposed to X-rays, which indicates that it has weak dielectric properties. 相似文献
55.
Tevfik Tozkoparan Emre Ulas Macit Olcer Cavit Arikan Meric Batmaz Aylin Saracoglu Goknur Murat Ozyilmaz Sevgi Kayhan Ebru Soydas Izmir Branch Archives Noyan Sancar Mehmet Yasa Guven Incirlioglu 李璠 《世界建筑》2010,(7):26-31
<正>一座建筑的性能应当如何来衡量?除了通过统治当代建筑舆论的美学、技术以及经济价值来进行描述之外,我们还能够如何来阐释一座建筑,尤其是一座致力于庇护那些渴望展现自己的艺术家的建筑?有人会问成功的表演是如何实现的,表演者是如何进行伪装的、又是如何展现自己的?根据海德格尔的理论,当我们看不到钉子的时候,铁锤的表现才是成功的;钉子本身的出现通常表明出现了问题。 相似文献
56.
The effect of slip in flows of power-law liquids past smooth spherical particles is numerically studied by using Navier’s linear slip model. For computational simplicity, a sphere-in-sphere type computational domain has been chosen. Thus, the governing conservation equations of mass and momentum are considered in spherical coordinates. These are solved by using a finite difference method-based simplified marker and cell algorithm implemented on a staggered grid arrangement. The non-Newtonian terms of the momentum equation are discretized by a second-order central differencing scheme, whereas the convective terms are discretized by using QUICK scheme. The reliability and accuracy of the solver is established by comparing the present numerical results with the existing literature counterparts. Furthermore, extensive new results are obtained in the range of conditions for Reynolds number, Re: 0.1–200; power-law behavior index, n: 0.5–1.6; and a dimensionless slip parameter, λ: 0.01–100. Finally, effects of these dimensionless parameters on near surface flow kinematics are thoroughly delineated. 相似文献
57.
58.
Kutlu B. Kavaklıoğlu Süheyla Aydin Miray Çelikbilek A. Erçin Ersundu 《International Journal of Applied Glass Science》2015,6(4):406-418
Thermal behavior, structural properties, and phase equilibria of the (100−x)TeO2-xNa2O system were studied in the 5 ≤ x ≤ 50 mol% composition range. Investigation of glass formation behavior in the binary system was realized, and the glass formation range was determined as 7.5 ≤ x ≤ 40 mol%. Differential thermal analysis (DTA) and Fourier transform infrared (FTIR) spectroscopy techniques were used for thermal and structural characterization of the glasses. Influence of Na2O content on glass transition temperature (Tg), glass stability (∆T), density (ρ), molar volume (VM), oxygen molar volume (VO), and oxygen packing density (OPD) values of sodium tellurite glasses was evaluated considering the structural transformations in the glass network. For the phase equilibria studies, DTA, X-ray diffraction (XRD), and scanning electron microscopy/energy dispersive X-ray (SEM/EDS) techniques were utilized to characterize the heat-treated samples. According to the phase equilibria studies, three eutectic regions were detected in the 0 < x < 50 mol% composition range of the (100−x)TeO2-xNa2O system. A new invariant endothermic reaction was detected for the compositions between 40 ≤ x ≤ 45 mol%. Na2O.8TeO2 (11.11 mol% Na2O) compound that was claimed to exist in the binary system in the literature was found to be the metastable δ-TeO2 phase. 相似文献
59.
预应力框架弯矩调幅规律与连续梁相比有着自己的特点,通过对柱梁线刚度比、外荷载形式、次弯矩和柱铰可行性几个方面进行分析,希望可以对预应力框架弯矩调幅设计提供一点参考和帮助。 相似文献
60.
Ivan Spasojevic Ines Batinic-Haberle Dubravka Barisin 《Propellants, Explosives, Pyrotechnics》1993,18(2):89-92
The igniter consisting of 34% Mg, 60% KNO3, 3% KClO4 and 3% organic binder was subjected to accelerated aging under the conditions of 85% relative humidity at 65°C, 75°C and 85°C, and at 75°C with 92% relative humidity. Chemical aging was followed through formation of Mg(OH)2 and KNO2. Functional characterization was accomplished in a device constructed to enable simultaneous determination of the heat of combustion and pressure-time recording of the combustion process of both fresh and aged samples. The maximum acceptable deterioration occured at different times depending upon the conditions. The acceleration factor for every 10°C at 85% relative humidity is on average 2.8, leading to a prediction of shelf life of not more than 4 years at 25°C. At the time when burning characteristics were significantly changed, the mixture suffered only slight chemical changes, with only about 1% Mg(OH)2 and 0.5% KNO2 being formed. Thus, no chemical changes should be tolerated in such formulations. 相似文献