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1.
选用新方法合成了2-碘—N-甲基苯磺酰胺,通过^1H NMR,^13C NMR,^13C DEPT NMR(Distortionless Enhancement by Polarization Transfer NMR)和MS确证的其结构。 相似文献
2.
本文用石蜡模拟油垢,用^60Co放射源的1.25MeV平均能量的γ射线垂直入射,以一定的散射角和不同的探测立体角接收散射γ光子敫.发现散射γ计数与被测石蜡厚度之间存在不同的线性关系.结果发现,放射源与探测器之间屏蔽的好坏和合理的探测距离对提高线性度有很大关系.本实验测得最佳线性相关系数平方值为0.9981,平均测量精度为1.26mm.这对研究散射法检测油垢厚度和选择合适的探测距离提供了实验基础. 相似文献
3.
In this article,we consider Orlicz-Lorentz sequence spaces equipped with the Orlicz norm(λφ,ω,‖·‖Oφ,ω) generated by any Orlicz function and any non-increasing weight sequence.As far as we know,research on such a general case is conducted for the first time.After showing that the Orlicz norm is equal to the Amemiya norm in general and giving some important properties of this norm,we study the problem of existence of order isomorphically isometric copies of l∞... 相似文献
4.
Ye Gao YIN* Willis FORSLING Dan BOSTR諱 Oleg ANTZUTKIN Mats LINDBERG Alexander IVANOV Department of Chemistry Faculty of Science The University of Shantou Shantou Division of Inorganic Chemistry Department of Chemical Metallurgical Engineering Lule?University of Technology. Lule?se- Sweden Department of Chemistry Ume University Ume se-- Sweden 《中国化学快报》2003,14(2)
Owing to the particular affinity toward metal ion and changeable dentation, dialkyldithiophosphates are commonly used ligands in preparation of the transition metal complexes with variable structures1. For instances relevant to this work, the IIB metal complexes defined crystallographically so far have provided the examples as follows2-12 (Scheme 1). Scheme 1 The frameworks of IIB metal complexes of dialkyldithiophosphate MMMMMMMMMM a b c d … 相似文献
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ZHAO Chunxia XU Guowang SHI Xianzhe MA Jianmei ZHANG Yan L?Shen & YANG Qing . Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian China . Cell Laboratory Second Affiliated Hospital Dalian Medical University Dalian China 《中国科学B辑(英文版)》2004,47(2):166-172
With the accomplishment of Human Genome Project (HGP), single nucleotide polymorphism (SNP) and mutation detection in human genome are becom-ing a new researching focus. These researches can help us to understand the phenotype diversity of indi-vidual, disease susceptibility and drug resistance of different colonies. Traditional method used for muta-tion detection is slab gel electrophoresis, which re-mains labor-intensive and time-consuming because of the requirement of radioactivity or te… 相似文献
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We propose and experimentally validate an optical true time delay beamforming scheme with straightforward integration into hybrid optical/millimeter(mm)-wave access networks. In the proposed approach, the most complex functions, including the beamforming network, are implemented in a central office, reducing the complexity and cost of remote antenna units. Different cores in a multi-core fiber are used to distribute the modulated signals to high-speed photodetectors acting as heterodyne mixers. The mm-wave carrier frequency is fixed to 50 GHz(VBand), thereby imposing a progressive delay between antenna elements of a few picoseconds. That true time delay is achieved with an accuracy lower than 1 ps and low phase noise. 相似文献
9.
Numerical tests of theoretical models describing ionization of H(1s) atom by linearly polarized flat pulse of laser radiation
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We derive the well-known Coulomb correction factor for the Gordon-Volkov wave function describing an outgoing electron in the process of ionization in an intense laser field. Although rigorous treatment would limit its use only to laser fields much lower than the so-called barrier-suppression field, it appears that in practice the correction factor may be used also close to and even above this critical value of the laser field. We compare predictions of several analytical expressions describing ionization rate of the hydrogen atom in its ground state in the strong linearly polarized laser field. We also compare ionization probabilities obtained by integrating these ionization rates over a temporal envelope of the laser pulse with predictions based on the exact numerical solution to the time-dependent Schr ¨odinger equation. 相似文献
10.
In this paper certain classes of meromorphic functions in punctured unit disk are defined. Some properties including coefficient inequalities, convolution and other results are investigated. 相似文献