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排序方式: 共有9795条查询结果,搜索用时 15 毫秒
991.
992.
基态He2Ne^+分子结构与性质的理论计算 总被引:1,自引:0,他引:1
利用Gaussian 92程序和UHF/6-31G方法,计算了基诚He2N3^+分子的结构、能量,振动光主、热化学数据与静电参数。得到线型和弯曲的两处平衡结构。 相似文献
993.
New results on elements 111 and 112 总被引:1,自引:0,他引:1
S. Hofmann F.P. Heßberger D. Ackermann G. Münzenberg S. Antalic P. Cagarda B. Kindler J. Kojouharova M. Leino B. Lommel R. Mann A.G. Popeko S. Reshitko S. Śaro J. Uusitalo A.V. Yeremin 《The European Physical Journal A - Hadrons and Nuclei》2002,14(2):147-157
Experiments on the synthesis and identification of the nuclei 272111 and 277112 were performed in order to confirm previous results. Three additional decay chains were measured in the reaction 64Ni + 209Bi →273111*. The study revealed considerably improved data on the decay chain originating from 272111. One additional chain was measured in the reaction 70Zn + 208Pb →278112*. The decay properties of the chain starting at 277112 are in excellent agreement with the second chain of the first experiment down to 265Sg, where the new chain ends by a previously unknown spontaneous-fission branch. A re-analysis of all the data on elements
110, 111, and 112 measured at GSI since 1994 (a total of 34 decay chains was investigated) revealed that for 2 chains (the
second chain of 269110 measured in 1994 and the first chain of 277112 measured in 1996) the results of the new analysis differed from the previous one. In all other cases the earlier data
are exactly reproduced.
Received: 21 December 2001 / Accepted: 15 January 2002 相似文献
994.
Six surface models for the Fe3O4(1 1 0) surface were studied using the density functional theory (DFT), namely the AB-terminated surface (AB model), the AB-terminated with FeA vacancy (AB-FeA vac model), the AB-terminated with FeB vacancy (AB-FeB vac model), the B-terminated surface (B model), the B-terminated surface with FeB vacancy (B-FeB vac model), and the B-terminated surface with O vacancy (B-O vac model). Here, A and B denoted the Fe cations in tetrahedrally (FeA) and octahedrally (FeB) coordinated interstices. The stability, the electronic structure and the magnetic properties of the six surface models were also calculated. The results predict that the B-O vac model is more stable than other surface models. The half-metallic property remains in the AB and B models, while the other four surface models exhibit metallic properties. At the same time, the AB, AB-FeA vac, AB-FeB vac, B and the B-FeB vac models have ferrimagnetic properties, while the B-O vac model has antiferromagnetic property. 相似文献
995.
Based on a review of the current literature, a surface phase diagram is proposed for the submonolayer Au on Si(111) system. Kinetic considerations are reviewed and key surface phase diagram features such as the Θ < 0.4 ML metastable
structure and the high temperature
to Si(111)-(1 × 1)Au second order phase transition are discussed. Experiments to verify certain portions of the phase diagram are proposed. 相似文献
996.
The stability of high‐frequency potential surface waves at a dense magnetized plasma – metal interface with respect to a low‐frequency plasma density modulation is studied in the point of view of the surface waves control. The discussion is addressed to the situation, when an external steady magnetic field is directed perpendicularly to the interface. The nonlinear interaction process of the high‐frequency surface wave, its satellites and the low‐frequency plasma density perturbation is investigated. It is shown that the low‐frequency plasma density perturbation can be represented as a superposition of forced waves of surface and volume types and can lead to an additional attenuation of the surface waves. This attenuation arises when the surface wave amplitude exceeds the threshold value. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
997.
Martin L. Banson Gary P. Cofer Laurence W. Hedlund G. Allan Johnson 《Magnetic resonance imaging》1992,10(6):929-934
An inductively coupled surface coil for imaging the rat spine at 7 T is described. This planar circular probe was made from microwave substrate to limit the size of the coil and to minimize the magnetic susceptibility. The surface coil was used as a single transmit/receive coil and as a receive-only coil with a birdcage body coil for excitation. The signal-to-noise ratio (SNR) of the probe was compared to a 5-cm birdcage coil and exceeded the birdcage coil's SNR by three to six times at superficial structures. The main advantages of the probe are an improved SNR for superficial structures and a simple design and use. Images with 50 × 50 × 500 μm voxels were obtained of the rat spine with excellent anatomical detail. 相似文献
998.
999.
Angel Licea-Claverıe Simona Schwarz Frank Simon Omar Urzúa-Sánchez Jürgen Nagel Dieter Pleul Klaus-Jochen Eichhorn Andreas Janke 《Colloid and polymer science》2005,283(8):826-835
The polycation preparation of poly(dimethylaminoethylmethacrylate) hydrochloride and the multilayer formation in combination with poly(sodium 4-styrenesulphonate) as polyanion studies onto different substrates, as followed by streaming potential measurements, in situ surface plasmon resonance spectroscopy, and multi-wavelength ellipsometry, are reported. Furthermore, we studied the resulting multilayer buildup of dry surfaces by UV-Vis spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy measurements. Thereby, the layer built up at the solid/liquid-interface could be followed and quantified at the molecular level.This revised version was published online in April 2005 with corrections to the article category. 相似文献
1000.
I. Nachev 《Il Nuovo Cimento D》1990,12(8):1143-1151
Summary The subband structure of the narrow-gap semiconductor Hg1−x
Cd
x
Te is investigated theoretically at finite temperature by a modified sixbandk·p model based on the effective-mass approximation. A study of the complete surface energy spectrum is reported. The mobile,
bound and resonant states are treated by considering energy states in a large quantum box. The theory is applied to cases
with strong interband interaction when the resonant character of the subband states is prominent.
The authors of this paper have agreed to not receive the proofs for correction. 相似文献