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161.
The microwave spectrum of 1-thia-closo-dodecaborane(11), 1-SB(11)H(11), has been investigated in the 23-62 GHz spectral region. The molecule is found to have C(5v) symmetry. The spectra of several isotopomers have been assigned and a precise substitution structure of the non-hydrogen atoms has been determined. The structure is in quite good agreement with the one determined previously by electron diffraction. Density functional theory calculations at the B3LYP/cc-pVTZ level were found to predict a structure that is in good agreement with the substitution structure. 相似文献
162.
Karásek P Planeta J Varad'ová Ostrá E Mikesová M Goliás J Roth M Vejrosta J 《Journal of chromatography. A》2003,1002(1-2):13-23
Direct supercritical fluid extraction (SFE) of wines with carbon dioxide was compared to SFE of the sorbent used for solid-phase extraction of the same wine samples (SPE-SFE). Compared to SPE-SFE, the direct SFE results in amore specific and representative gas chromatographic fingerprint of the wine sample. The multivariate statistical processing of the direct SFE-GC data provides a clear-cut and sharp discrimination among the individual wine varieties while the discrimination based on the SPE-SFE-GC data is relatively poor. This finding reflects the adverse effects of additional analyte-sorbent interactions and sorption/desorption steps involved in SPE-SFE. 相似文献
163.
Volume Contents
Contents of Volume 23 (2003) 相似文献164.
The progress in the field of high resolution X-ray microscopy is caused in particular by the rapid developments of synchrotron radiation sources and X-ray optical elements, by the extension of the energy range, improved designs of X-ray microscopes and scanning X-ray microscopes, the use of CCD detectors with high detective quantum efficiency, the introduction of new imaging techniques, and the development of new fields of application. 相似文献
165.
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167.
Entwicklung eines Produktes zweier Kugelfunktionen mit verschiedenen Argumenten nach Kugelfunktionen
Josef Meixner 《Archiv der Mathematik》1948,1(3):173-181
Ohne Zusammenfassung 相似文献
168.
A critical review of the phonon-assisted hopping theory of the dc conductivity σ is given. It is argued that the current theories either contain uncontrollable approximations, or they yield the result of the same order of magnitude as the approximations used or they may also lead to temperature dependence of σ other than that described by the Mott law. For the simplest usually accepted model of amorphous Ge (a-Ge), the low-temperature asymptote of σ is obtained in the form of a power law. In the experimental part of the work, careful measurements from 300 down to 8 K are reported, both for the pure and the gold-doped a-Ge films. Since the results of such measurements yield a straight line in a wide interval of temperature both in the log σ versus and log σ versus log T scale, the power law appears to be equally well justified as the Mott law, both from the point of view of theory and that of experiment. 相似文献
169.
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Monatshefte für Mathematik - 相似文献