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排序方式: 共有314条查询结果,搜索用时 15 毫秒
91.
92.
M. Asai J. L. Bailly H. B?ttcher F. Bruyant C. Caso Y. Chiba H. Dibon B. Epp A. Ferrando F. Fontanelli S. N. Ganguli T. Gémesy R. Hamatsu P. Hidas T. Hirose J. Hrubec T. Kageya N. Khalatyan E. Kistenev I. Kita S. Kitamura V. Kubik J. MacNaughton M. Markytan S. Matsumoto I. S. Mittra L. Montanet G. Neuhofer G. Pinter P. Porth T. Rodrigo J. Singh S. Squarcia K. Takahashi R. Tanaka L. A. Tikhonova U. Trevisan R. Wischnewski T. Yamagata S. A. Zotkin NA EHS-RCBC Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):593-598
Properties of proton diffractive dissociation have been investigated for four-prong final states in proton-proton reactions at 360 GeV/c, in particular forpp→ppπ +π? mπ 0(m=0,1,2). Mass distributions and decay angular distributions are given. The decay of the diffractive system is seen to be very anisotropic, and largep T is suppressed at higher masses. It is found that the “pomeron” couples with a single valence quark of the incident proton, but indications for a diquark-pomeron coupling are also found. Similarities with fragmentation in lepton-hadron deep inelastic scattering are underlined. 相似文献
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94.
新型燃料电池质子交换膜──含叔丁基的磺化聚芳醚砜 总被引:5,自引:1,他引:4
以3,3'-二磺酸钠基-4,4'-二氯二苯砜(SDCDPS)、叔丁基对苯二酚(TBHQ)、二氟二苯酮(DFBP)为原料,利用亲核缩聚反应,通过调整磺化单体(SDCDPS)和非磺化单体(DFBP)的比例与叔丁基对苯二酚(TBHQ)共聚,合成了不同磺化度的聚芳醚砜.聚合物成膜后的研究结果表明,该膜具有良好的机械性能和电化学性能,可能在质子交换膜燃料电池中得到应用. 相似文献
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96.
以4,4′,4″ 三氨基三苯胺为母体,以含有4种不同取代基的萘酚AS为偶合组分合成了一系列三芳胺三偶氮类有机光导颜料.用元素分析、红外光谱、紫外光谱、质谱和X射线衍射光谱对结构进行了表征.研究结果表明,含硫杂环三偶氮类有机光导颜料在520-730nm之间都有较强吸收. 相似文献
97.
99.
The dynamics of modulated waves are studied in the one-dimensional discrete nonlinear electrical transmission line. The contribution of the linear dispersive capacitance is taken into account, and it is shown via the reductive perturbation method that the evolution of such waves in this system is governed by the higher-order nonlinear Schrödinger equation. Passing through the Stokes analysis, we establish a generalized criterion for the Benjamin-Feir instability in the network and determine the exact solutions of the obtained wave equation by using the Pathria-Morris approach. 相似文献
100.
The strong infrared absorption in the ν3 S–F stretching region of sulphur hexafluoride (SF6) near 948 cm?1 makes it a powerful greenhouse gas. Although its present concentration in the atmosphere is very low, it is increasing rapidly, due to industrial pollution. The ground state population of this heavy species is only 32% at room temperature and thus many hot bands are present. Consequently, a reliable remote-sensing spectroscopic detection and monitoring of this species require an accurate modelling of these hot bands. We used two experimental set-ups at the SOLEIL French synchrotron facility to record some difference and combination bands of SF6: (1) a new cryogenic multiple pass cell with 93 m optical path length and regulated at 163 ± 2 K temperature and (2) the Jet-AILES supersonic expansion set-up. With this, we could obtain high-resolution absorption spectra of the ν3 ? ν1, ν3 ? ν2, ν1 + ν3 and ν2 + ν3 bands at low temperature. These spectra could be assigned and analysed, thanks to the SPVIEW and XTDS computer programs developed in Dijon. We performed two global fits of effective Hamiltonian parameters. The first one is a global fit of the ground state, ν2, ν3, ν3 ? ν2, ν2 + ν3, 2ν3 and 2ν3 ? ν3 rovibrational parameters, using the present spectra and previous infrared, Raman and two-photon absorption data. This allows a consistent refinement of the effective Hamiltonian parameters for all the implied vibrational levels and a new simulation of the 2ν3 + ν2 ? ν2 hot band. The second global fit involves the present ν3 ? ν1 and ν1 + ν3 lines, together with previous ν1 Raman data, in order to obtain refined ν1 parameters and also ν1 + ν3 parameters in a consistent way. This allows to simulate the ν3 + ν1 ? ν1 hot band. 相似文献