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981.
V. Vescoli F. Zwick W. Henderson L. Degiorgi M. Grioni G. Gruner L.K. Montgomery 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(3):503-511
Combined optical and photoemission experiments on the quasi-one dimensional Bechgaard salts reveal the non-Fermi liquid character
of these prototype quasi-one dimensional interacting electron systems. We show that various aspects of the exotic normal state
properties along the chains are consistent with the predictions of the Tomonaga-Luttinger liquid theory. We also discuss the
effect of interchain coupling on the insulator-metal transition, associated with the electron confinement-deconfinement crossover.
Received 17 May 1999 and Received in final form 13 July 1999 相似文献
982.
In this contribution, we highlight the state of the art in the determination of structures with ultrafast electrons and X‐rays. We provide our perspectives and reflections on the principles, techniques and methods, and on applications from different disciplines, with some focus on physical, chemical and biological structures. Although this article is not a survey of all the work done with these techniques, it provides a comprehensive referencing to current research. 相似文献
983.
《Colloids and surfaces. A, Physicochemical and engineering aspects》2000,170(2-3):107-112
The calcium phosphate which corresponds to the formula Ca3(PO)4 · nH2O (2<n<3) was isolated from solutions with Ca/P molar ratio 0.2 and pH 7. The compound was characterised by chemical and thermogravimetric analyses, Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction. The FTIR spectra were compared with spectra of β-tricalcium phosphate (β-TCP) in the atlases for analysis of urinary calculi and other literature data. 相似文献
984.
V. Tsurkan St. Plogmann M. Demeter D. Hartmann M. Neumann 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,15(3):401-403
X-ray photoelectron spectroscopy was used to investigate ACr2S4 (, Zn, Mn, Fe, Fe:Cu) and BCr2Se4 (, Cu, Hg, Hg:Cu) single crystals. Well defined splitting of the Cr 2p core level has been found. The local magnetic moments of the Cr ions are responsible for the observed effect.
Received 2 November 1999 相似文献
985.
986.
在部分相干理论的基础上,分别用表观传递函数和能量分布作评价指标,计算了部分相干光学系统的最佳象面位置,并讨论了其与相干度、空间频率及象差的关系。 相似文献
987.
S. V. Shishkina S. M. Desenko K. G. Nazarenko O. V. Shishkin 《Journal of Structural Chemistry》2005,46(1):191-194
X-ray diffraction investigation showed that protonation of 4H-benzo-[1,4]-oxazin-3-ylidene-cyclohexylamine occurs at the exocyclic nitrogen atom. In crystal, the cation has a structure with a distinct exocyclic C=N bond. 相似文献
988.
Thin films of Cu(In,Ga)Se2 were fabricated by evaporation from ternary CuGaSe2 and CuInSe2 compounds for photovoltaic device applications and their properties were investigated. From XRF analysis, the Cu:(In+Ga):Se atomic ratio in all thin films was approximately 1:1:2. The Ga/(In+Ga) atomic ratio in the thin films changed linearly from 0 to 1.0 with increasing the [CGS]/([CGS]+[CIS]) mole ratio in the evaporating materials. However, for thin films prepared at the [CGS]/([CGS]+[CIS]) mole ratio above 0.4, the composition by EPMA analysis was not consistent with that by XRF analysis. The result of EPMA analysis showed that the surface of a thin film was Cu-rich. XRD studies demonstrated that the thin films prepared at the [CGS]/([CGS]+[CIS]) mole ratio under 0.2 had a chalcopyrite Cu(In,Ga)Se2 structure and the preferred orientation to the 112 plane. On the other hand, XRD patterns of the thin films produced at the [CGS]/([CGS]+[CIS]) mole ratio above 0.6 showed the diffraction lines from a chalcopyrite Cu(In,Ga)Se2 and a foreign phase. The separation of a peak was observed near 2θ=27°, indicative the graded Ga concentration in Cu(In,Ga)Se2 thin film. 相似文献
989.
The lattice parameters of CsBr at eight different temperatures from room temperature to 78.2 °K were measured and the true
lattice parameters were obtained by the least squares method using the Nelson-Riley extrapolation function. Using these parameters
the thermal expansion coefficients of CsBr were estimated at each temperature by fitting them into a cubic polynomial involving
temperatureT. Theα
T
thus obtained were compared with the values of earlier workers who used an interferometric technique and the agreement was
found to be good. 相似文献
990.
Junichiro Otomo Hitoshi Shigeoka Hiroshi Takahashi 《Journal of Physics and Chemistry of Solids》2005,66(1):21-30
Proton conduction and crystal structure in CsHSO4/SiO2 composite composed of polycrystalline CsHSO4 and mesoporous silica particles were investigated based on conductivity measurement and characterizations using Raman spectroscopy, XRD, and differential thermal analysis. The conductivity of pure CsHSO4 abruptly changes at around 414 K (superprotonic phase transition), being accompanied with the structural transformation from a monoclinic phase to a tetragonal phase, while the conductivity of CsHSO4/SiO2 composite is significantly larger by over three orders of magnitude than that of pure CsHSO4 below the critical temperature of the superprotonic phase transition (353-414 K). Raman spectroscopy and XRD indicate that this remarkable conductivity-enhancement in the composite is not due to the stabilization of the tetragonal phase (superprotonic phase) below its critical temperature. The line-broadening of the internal modes in the Raman spectra suggests that the rapid reorientational motion of the HSO4− ion, which leads to superprotonic conduction, is induced in the composite even below the critical temperature. The reorientational motion of the HSO4− ion below the critical temperature will occur at the interfacial phase which is structurally disordered and forms between CsHSO4 and SiO2 in the mesopores and/or on the surfaces of silica particles. Proton transfer will be accelerated via the interfacial conduction-pathway in the composite. 相似文献