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961.
Aki Hayashi Hirokazu Nakayama Taro Eguchi Nobuo Nakamura Mitsutomo Tsuhako 《Molecular Crystals and Liquid Crystals》2013,570(2):573-578
Abstract Two kinds of diethylenetriamine (2E3A) intercalation compounds of α-zirconium phosphate with different interlayer distances could be obtained by regulating the reaction time and temperature. Phase I (d = 10.2 Å) slowly transforms to Phase II(d = 15. 8 Å) with transformation enthalpy of 30 kJ-mol?1 in 2E3A aqueous solution. The conformation of 2E3A in Phase I and Phase II were confirmed to be bent and all trans (straight) forms by31P MAS NMR and XRD measurements. Two phases have different adsorption behavior for gaseous carboxylic acids. Phase II can adsorb considerable amount of carboxylic acids whereas Phase I adsorb a little. 相似文献
962.
963.
964.
Minghui Shen 《代数通讯》2013,41(6):2202-2232
In this article, we define and study a new concept of projective Brauer characters. Following the direct approach as taken in Navarro (1998) and Isaacs (1975), we study the resulting projective blocks of projective Frobenius characters and projective Brauer characters of a given group determined by certain linkage condition as an introduction to a projective extension of classic Brauer theory. 相似文献
965.
966.
Mircea Crasmareanu 《Nonlinear Analysis: Real World Applications》2012,13(4):1551-1561
Given a pair (metric g, symmetric 2-covariant tensor field H though as a Rayleigh dissipation) on a path space (manifold M, semispray S), the family of nonlinear connections N such that H equals the dynamical derivative of g with respect to (S,N) is determined by using the Obata tensors. In this way, we generalize the case of metric nonlinear connections as well as that of recurrent metrics. As applications, we treat firstly the case of Finslerian (α,β)-metrics finding all nonlinear connections for which the associated Finsler-Sasaki metric is exactly the dynamical derivative of the Riemannian-Sasaki metric. Secondly, we apply our results for the case of Beil metrics used in Relativity and field theories. 相似文献
967.
968.
We carried out a comparative study of the thermal dilatation coefficient of molybdenum trioxide with and without Nd3+ doping. The doped samples were obtained from a solid state reaction of MoO3 and Nd2O3 in concentrations from 0.2 to 20.0 at%. The prepared samples were analyzed as a function of the temperature through X-Ray diffraction (XRD), the chemical composition of the resultant material was studied using Energy Dispersive X-ray Spectroscopy (EDS). The results of the XRD show that the MoO3 doped with Nd in concentrations of 0.2 and 1.0% atomic grows iso-structurally with α-MoO3. Moreover, MoO3 doped with Nd3+ in concentrations of 5.0, 10.0 and 20.0% atomic exhibits the monoclinic phase Mo9O26. Finally, we determined that the values of the thermal expansion coefficient of MoO3, doped and un-doped, differ by less than 3%. 相似文献
969.
Flood disasters are one of the most common and destructive natural hazards all over the world. In this paper, improved interior-outer-set model (IIOSM) based on information diffusion theory is introduced in detail to assess flood risk in an effort to obtain accurate analytical results that represent the actual situation. Then fuzzy α-cut technique is applied to calculate the fuzzy expected values under the possibility–probability distribution (PPD) calculated by IIOSM. Taking the value of α throughout the interval (0, 1], we correspondingly get access to the conservative risk value (RC) and venture risk value (RV). Selection of α, RC and RV is dependent on present technical conditions and risk preference of different people. To illustrate the procedure of IIOSM and fuzzy α-cut technique, we employ them respectively to analyze the flood risk in Sanshui District, located in the center of Guangdong province in China. The results, such as risk value estimations, as well as fuzzy expected values, i.e. RC and RV under the given α-cut level, can reflect the flood risk quite accurately. The outcomes of this research based on IIOSM and fuzzy α-cut technique offer new insights to carry out an efficient way for various flood protection strategies. 相似文献
970.
W.-L. Feng 《Optik》2009,120(14):696-2699
In this paper, the optical absorption spectra of Yb3+ in the α-Al2O3 crystal are reasonably explained by using the superposition model and local lattice structure analysis. Based on these studies, we find that the local geometrical structure around the Yb3+ ions possesses an elongated trigonal distortion above the O2−-triangle and a compressed trigonal distortion in the lower one. 相似文献