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1.
以工业偏钛酸、硫酸锌、氨水为主要原料,用直接沉淀法并进行热处理得到钛酸锌粉体,并用XRD对产物成分进行了检测。结果表明,不同的锌钛比对钛酸锌(ZnO-TiO2)体系的成分有较大影响。 相似文献
2.
通过适当的工艺措施,采用Bridgman法生长了直径为30mm的X射线及γ射线探测器级的Cd.9Zn0.1Te晶锭.测试结果表明:该晶锭结晶质量良好,位错密度低,成分均匀,杂质含量低,红外透过率和电阻率都十分接近本征Cd.9Zn0.1Te的值.并从晶体的生长特性、缺陷和杂质的角度,分析了生长高性能晶体的条件,研究了生长Cdl-xZnxTe晶体的x值与缺陷和杂质浓度之间的关系. 相似文献
3.
T. S. Lee S. B. Lee J. M. Kim J. S. Kim S. H. Suh J. H. Song I. H. Park S. U. Kim M. J. Park 《Journal of Electronic Materials》1995,24(9):1057-1059
In order to improve the Zn homogeneity along the axial direction of CdZnTe boule, we have employed a modified Bridgman technique
using a (Cd, Zn) alloy source in communication with the melt, whose temperature has been gradually changed from 800 to 840°C
during growth. Electron probe microanalysis (EPMA) measurements of Zn composition in the boule shows an excellent homogeneity
of Zn along the axis of the CdZnTe boule compared with results in a boule grown by using a fixed source temperature. We have
performed a numerical simulation to obtain the approximate temperatures of additional heating and cooling needed to improve
the radial Zn homogeneity. CdZnTe boule has been grown by seeded vertical Bridgman furnace with two zones of heater and cooler.
Ultraviolet/visible spectroscopic measurements of Zn composition over the length of the boule indicate that the radial distribution
of Zn composition is very homogeneous in the body region of the boule, where the radial variation of Zn composition is ±0.0005. 相似文献
4.
5.
The employment of the Zn(Se,Te) pseudo-graded contacting scheme to p-type ZnSe-based alloys contributes directly to the recent
demonstration of room temperature continuous-wave operation of II– VI green-blue laser diodes. Contact ohmicity is maintained
down to cryogenic temperatures which enabled the investigation of electrical transport properties associated with the p-type
nitrogen-doped ZnSe, Zn(S,Se), and (Zn,Mg)(S,Se). The observation of both persistent photoconductivity and a metastable population
of holes which are in thermodynamic equilibrium with hydrogenic acceptors having reduced activation energy suggests the presence
of a DX-like behavior for holes in p-type (Zn,Mg)(S,Se). 相似文献
6.
对Zn-22%Al超塑性合金进行了等温超塑压缩试验。在相同的温度、变形速率条件下,研究了不同的变形强度与流动应力及硬度,以及在相同的温度、变形程度条件下,不同的变形速率与流动应力等的关系。 相似文献
7.
By the NSS test and the test in SO2 gas atmosphere and detecting the φcorr-t curves, Rp-t curves and the cyclic voltammogram curves, the corrosion resistance of the electroplated Zn-Co alloy coating was studied. The corrosion resistance of the electroplated Zn-Co alloy coating is three times higher than that of the galvanized coating. Because the corrosion resistance of the Zn-Co alloy coating is especially remarkable in SO2 gas atmosphere, it is particularly fit to be used as a protective coating in industrial atmosphere. The reason why the Zn-Co alloy coating has such a high corrosion resistance is that its corrosive product has a comparatively great role in depressing the corrosive process. 相似文献
8.
研究了在250℃、不同挤压比下挤压变形对Mg95 Zn4.3 Y0.7合金组织及性能的影响。结果表明,Mg95 Zn4.3 Y0.7经过挤压变形后,合金中晶界处的共晶相破碎,弥散分布至晶粒内部,并且晶粒显著细化。同时,随着挤压比的增大,晶粒细化程度增加,合金的力学性能单调增加。当挤压比为16时,合金晶粒尺寸为5-8μm,抗拉强度为288.9MPa,显微硬度HV值为117.8。 相似文献
9.
Numerical analysis of galvanic corrosion of Zn/Fe interface beneath a thin electrolyte 总被引:1,自引:0,他引:1
Jong-Min Lee 《Electrochimica acta》2006,51(16):3256-3260
A numerical analysis of galvanic corrosion of a Zn/Fe interface beneath a thin layer electrolyte is presented. Specifically, a circular defect, where the zinc coating has been removed, is considered. It is assumed that both oxygen reduction and iron oxidation can occur on the Fe surface, while only zinc oxidation occurs on the Zn surface. The importance of electrolyte thickness and conductivity and defect radius is considered. It is assumed that the iron and zinc oxidation rates are described by a Tafel relationship. If the kinetic parameters of the oxidation reactions are known, the cathodic protection of Fe is a function of a Wagner number, the ratio of the electrolyte thickness to the defect radius, and the ratio of the radius of the defect to the outer radius of the zinc layer. 相似文献
10.