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981.
Journal of Applied Spectroscopy - 相似文献
982.
Michael J. Puls 《Archiv der Mathematik》2007,88(6):500-506
Let p be a real number greater than one. In this paper we study the vanishing and nonvanishing of the first L
p
-cohomology space of some groups that have one end. We also make a connection between the first L
p
-cohomolgy space and the Floyd boundary of the Cayley graph of a group. We apply the result about Floyd boundaries to show
that there exists a real number p such that the first L
p
-cohomology space of a nonelementary hyperbolic group does not vanish.
Received: 4 August 2006 Revised: 2 November 2006 相似文献
983.
This paper is concerned with the spectral analysis of a one-velocity transport operator with Maxwell boundary condition in
L
1-space. After a detailed spectral analysis it is shown that the associated Cauchy problem is governed by a C
0-semigroup. Next, we discuss the irreducibility of the transport semigroup. In particular, we show that the transport semigroup
is irreducible. Finally, a spectral decomposition of the solutions into an asymptotic term and a transient one which will
be estimated for smooth initial data is given. 相似文献
984.
In this paper we examine clathrate formation in the tetraisoamylammonium propionate-water binary system. We have found formation
of four polyhydrates, two of which are metastable over the whole temperature range studied. All polyhydrate crystals were
isolated and their compositions and densities determined; for (i-C5H11)4NC2H5COO·36.5H2O, unit cell parameters were additionally found. The results are compared with data for tetra-n-butylammonium carboxylate
polyhydrates, and the structure of the title compounds is suggested. It is confirmed that the isoamyl radical stabilizes the
tetradecahedral void of the clathrate hydrate framework better than the n-butyl radical.
Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 3, pp. 67–71, May–June, 1994.
Translated by L. Smolina 相似文献
985.
986.
L. G. I. Bennett A. M. C. Harnden B. J. Lewis 《Journal of Radioanalytical and Nuclear Chemistry》1994,180(2):209-216
Normally, gamma-ray spectroscopy is performed by equipment positioned in the SLOWPOKE-2 Facility at the Royal Military College; however, there have occasionally been requirements for analyses externally. A transportable gamma spectroscopy system was thus assembled by acquiring a commercially available multichannel analyzer, analysis program and detector, and by designing and constructing a transportable shielding castle. It was then used to take measurements of fission product concentrations at several research reactors. 相似文献
987.
C. Oproiu S. Marghitu S. Jipa I. Mihalcea 《Journal of Radioanalytical and Nuclear Chemistry》1994,181(1):109-116
This paper presents the results of an experimental study undertaken on the irradiation process of polyethylene tubing in an electron beam. Isodoses of distribution through material thickness in case of irradiation in one or two irradiation directions have been analyzed. 相似文献
988.
Classical methods of structural analysis cannot be applied to liquid crystals because higher order reflections disappear during the transition from crystal to liquid crystal due to the reduction in long range orientational and translational correlations. However, in order to relate physical properties to the molecular architecture, it is essential to have information about molecular positions and orientations in the crystalline state as well as in the liquid crystalline state. In this work, the transition from crystalline to liquid crystalline phase is carefully monitored and the relationship between the original lattice and the new molecular positions found using electron diffraction. In addition to this, a new high resolution electron-microscopic technique is described in which the positions of molecules in the crystalline and the quenched discotic phase are directly imaged and the defects observed in the crystalline and LC phase compared and quantitatively analysed. 相似文献
989.
Di[2-(4-substituted-phenyl)-3-mercapto-propenato]-nickel(II) complexes have been synthesized and investigated. All of them are mesomorphic; they have nematic phases with wide ranges and typical Schlieren textures. 相似文献
990.
V. I. Saloutin I. T. Bazyl' Z. E. Skryabina P. N. Kondrat'ev O. N. Chupakhin 《Russian Chemical Bulletin》1994,43(2):279-282
Reactions of pentafluorobenzoylpyruvic acid with amines afford the respective enamines. The intramolecular cyclization of the latter results inN-substituted 4-quinolone-2-carboxylic acids. Ammonia and triethylamine favor the cyclization of pentafluorobenzoylpyruvic acid to 2-carboxychromone.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 299–302, February, 1994. 相似文献