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151.
Kohno S. Teramoto Y. Lisitsyn I.V. Katsuki S. Akiyama H. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(3):778-785
The characteristics of a plasma generated by cable plasma guns have been studied by a laser interferometer. Cable plasma guns are frequently used as a plasma source in plasma opening switches. In our experiments, the plasma source consists of eight coaxial cable guns mounted on the outer electrode of concentric coaxial electrodes. The reproducibility of the gun in subsequent shots is found to be better than 10%, and the gun-to-gun difference is less than 15%. Assuming a symmetry of eight guns, the contour maps of the electron plasma density are plotted as functions of time. The plasma density becomes maximum near the gun nozzle and near the inner coaxial electrode. The plasma density is low in the area between the coaxial electrodes during the early time of the discharge. At a later time, the plasma fills the space between the two guns more uniformly. Still photographs of the plasma luminosity show a good correspondence with the plasma density plots which were taken 10 μs after the discharge initiation. The plasma gun system is designed for use in a 400-kA inductive voltage adder with the inductive energy storage system 相似文献
152.
K Fuji Y Watanabe T Ohtsubo M Nuruzzaman Y Hamajima M Kohno 《Chemical & pharmaceutical bulletin》1999,47(9):1334-1337
Straight chain compounds having a phenylisoserine unit and an oxetane ring at the alpha- and omega- position, respectively as extremely simplified analogues of taxol were prepared. None of these compounds showed promising tubulin inhibitory activity. 相似文献
153.
154.
A self-contained theory of the domain wall dynamics in ferromagnets under finite electric current is presented. The current has two effects: one is momentum transfer, which is proportional to the charge current and wall resistivity (rho(w)); the other is spin transfer, proportional to spin current. For thick walls, as in metallic wires, the latter dominates and the threshold current for wall motion is determined by the hard-axis magnetic anisotropy, except for the case of very strong pinning. For thin walls, as in nanocontacts and magnetic semiconductors, the momentum-transfer effect dominates, and the threshold current is proportional to V(0)/rho(w), V0 being the pinning potential. 相似文献
155.
Two different types of orthogonality condition models (OCM) are equivalently formulated in the Faddeev formalism. One is the OCM which uses pairwise orthogonality conditions for the relative motion of clusters, and the other is the one which uses the orthogonalizing pseudo-potential method. By constructing a redundancy-free T-matrix, one can exactly eliminate the redundant components of the total wave function for the harmonic-oscillator Pauli-forbidden states, without introducing any limiting procedure. As an example, a three--particle model interacting via the deep potential by Buck, Friedrich, and Wheatley is investigated. 相似文献
156.
A study has been made of the improvement of the hydrophobicity of a fluorine-polymer (polytetra-fluorinethylene, PTFE) by Ar-ion bombardment. Ar-ion bombardment to PTFE) by Ar-ion bombardment. Ar-ion bombardment to PTFE sheets was carried out at the fluences ranging from 3.1x10(20) to 18.3x10(20) ions/m(2). The beam current densities were ranged from 1.25 to 7.5 A/m(2). The hydrophobicity of modified materials has been investigated by means of a sessile drop method of water. The roughness, morphology and structure of bombarded specimens have been estimated as a function of beam current density and acceleration energy. It was found that Ar-bombardment causes the contact angle of water to increase from the original value 103 to 170 degrees. The results indicate that Ar-bombardment at an optional condition results in the formation of ultrahydrdophobic surfaces. The effects of Ar-bombardment to hydrophobicity of PTFE are discussed with the relationship among roughness, morphology and chemical bonding states of the surfaces. 相似文献
157.
The mass distributions obtained from a K?p experiment at 5.5 GeV/c are used to study the recent suggestion of an s-wave Kπ resonance at 1360 MeV. Using a model including s- and p- wave and , s-, p- and d-wave amplitudes, we analyze the spherical harmonic moments 〈Yl0〉 of the Kπ decay angular distribution in the K1 (1420) mass region and obtain the result that the reported mass of 1360 MeV does not necessarily represent the resonance position and is influenced by cuts made in the Kπ decay angle. 相似文献
158.
159.
R. Hamatsu S. Kitamura T. Yamagata M. Bogdanski E. Jeannet A.M. Cooper S.N. Ganguli A. Gurtu P.K. Malhotra U. Mehtani R. Raghavan A. Subramanian T. Emura I. Kita K. Takahashi H. Kohno L. Montanet 《Nuclear Physics B》1978,137(3):283-293
annihilations with ? 3 prongs with an incident antineutron momentum between 0.5 and 0.8 GeV/c are analysed. We present the topological branching ratios and cross sections, the resonance production rates and possible ?-ω interference effects. 相似文献
160.
Kirihara M Okubo K Uchiyama T Kato Y Ochiai Y Matsushita S Hatano A Kanamori K 《Chemical & pharmaceutical bulletin》2004,52(5):625-627
Thiols were converted into disulfide by the aerobic oxidation catalyzed by trichlorooxyvanadium in the presence of molecular sieves 3A. 相似文献