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991.
迄今未见任何稀土氨基酸络合物的ESR波谱报道,本文在合成Gd3+分别与甘氨酸、β-丙氨酸、谷氨酸、天冬氨酸和天冬酰胺五种氨基酸络合物的基础上,测定了不同温度下,水溶液、粉末及分子筛吸附样品的ESR谱,讨论了络合物中晶体场强,对称性及成键特性。 相似文献
992.
Preparation and Molecular Structures of Oligofunctional Dirhenium Carbonyl Derivatives from Dirhenium Nonacarbonylphosphane Starting with dirheniumdecacarbonyl, one CO-Ligand was eliminated oxidatively and substituted by the labile acetonitrile ligand. As an intermediate eq-Re2(CO)9NCCH3 was received. The reaction of this labilised carbonyl with tris(trimethylsilyl)phosphine and subsequent methanolysis gave ax-Re2(CO)9PH3, which was isolated and characterized for the first time. Photochemical and thermal reaction of ax-Re2(CO)9PH3 led to the new bi- and trinuclear complexes Re2(μ-H)(μ3-PHRe(CO)5)(CO)8, Re2(μ-PH2)2(CO)8 and Re2(μ-H) · (μ-PH2)(CO)8, which were characterized by IR-, 1H- and 31P-NMR spectroscopy. The structures of ax-Re2(CO)9PH3, Re2(μ-H)(μ3-PHRe(CO)5)(CO)8 and Re2(μ-PH2)2(CO)8 were confirmed by single-crystal X-ray analysis. ax-Re2(CO)9PH3 has a very short Re? P bond length of 228(2) pm. 相似文献
993.
叙述运用CWCO2相干激光雷达测量运动目标速度的原理和实验装置,并给出了实验结果,测速精度为0.01m/s速度分辨率为0.05m/s,外场实验表明,对于漫射目标,作用距离200m。 相似文献
994.
995.
新型的不锈钢镀Pt(Ir)电极 总被引:1,自引:0,他引:1
应用欠电位沉积与锚定效应,研制了一种新型的不锈钢镀Pt(Ir)电极,此电极具有优越的电化学特性,可望用于微传感器。 相似文献
996.
M. I. Dykman D. G. Luchinsky R. Mannella P. V. E. McClintock N. D. Stein N. G. Stocks 《Il Nuovo Cimento D》1995,17(7-8):661-683
Summary We outline the historical development of stochastic resonance (SR), a phenomenon in which the signal and/or the signal-to-noise
ratio in a nonlinear system increase with increasing intensity of noise. We discuss basic theoretical ideas explaining and
describing SR, and we review some revealing experimental data that place SR within the wider context of statistical physics.
We emphasize the close relationship of SR to some effects that are well known in condensed-matter physics.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
997.
Approximation of a laminated microstructure for a rotationally invariant,double well energy density 总被引:3,自引:0,他引:3
Mitchell Luskin 《Numerische Mathematik》1996,75(2):205-221
Summary. We give error estimates for the approximation of a laminated microstructure which minimizes the energy for a rotationally invariant, double well energy density . We present error estimates for the convergence of the deformation in the convergence of directional derivatives of the deformation in the “twin planes,” the weak convergence of the deformation
gradient, the convergence of the microstructure (or Young measure) of the deformation gradients, and the convergence of nonlinear
integrals of the deformation gradient.
Received July 25, 1995 / Revised version received November 20, 1995 相似文献
998.
本文研究了用金属有机物热发解法制备PLT8薄膜的工艺过程和基片对薄膜结构的影响,并且给出了铁电性能的测量结果。 相似文献
999.
采用自行研制的LB自动提膜装置,制备出大面积(10×8cm2)、高质量的PMMA超薄抗蚀剂膜,并将其用于高分辨率铬掩模版的研制。通过电子束曝光,湿法蚀刻,制作了分辨率优于0.5μm,特征线宽0.38μm的4(100mm)铬掩模版。 相似文献
1000.
The behavior of zirconium atoms at the W(100) surface associated with oxygen adsorption at different sample temperatures has been studied by Auger electron spectroscopy (AES), ion scattering spectroscopy (ISS), and the relative change of the work function (Δф) measured by the onset of the secondary electron energy distribution. The results have revealed: (i) adsorption of zirconium onto the W(100) surface followed by the elevation of the sample temperature up to 1710 K in an oxygen partial pressure of 2.7 × 10−4 induces complete diffusion of zirconium atoms into the W(100) substrate; (ii) further exposure of oxygen induces co-existence of oxygen and tungsten on the surface at 1710 K, resulting in a work function of 4.37 eV; (iii) keeping the sample temperature at 1710 K, simple evacuation of the system has resulted in surface segregation of zirconium atoms to the surface to form a zirconium atomic layer on the top-most surface, reducing the work function to 2.7 eV. The results have revealed that this specific behavior of zirconium atoms at high temperature assures, with very good reproducibility, the highly stable performance and long service life of Zr---O/W(100)-emitters in practical use, even in a low vacuum of 10−6 Pa. 相似文献