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211.
Near Hartree-Fock level ab initio molecular orbital calculations on H3O+ and a minimum energy structure with θ(HOH) = 112.5° and r(OH) = 0.963 Å and an inversion barrier of 1.9 kcal/mole. By comparing these results to calculations on NH3 and H2O, where precise experimental geometries are known, we estimate the “true” geometry of isolated H3O+ to have a structure with θ(HOH) = 110-112°, r(OH) = 0.97–0.98 Å and an inversion barrier of 2–3 kcal/mole. Our prediction for the proton affinity of water is ≈ 170 kcal/mole, which is somewhat smaller than the currently accepted value. 相似文献
212.
G. Peter 《Fresenius' Journal of Analytical Chemistry》1966,220(6):421-426
Summary It is outlined how the determination of Ca in food-stuffs by means of the oxalate method and potassium permanganate titration can be performed with sufficient accuracy. The influence of variable concentrations of the matrix elements P, Mg and Fe on the results is investigated.The relative standard deviation is of the order of ±0.3%. The given concentration of Ca in the presence of matrix elements is determined with an accuracy of ±0.5%.Zusammenfassung Es wird beschrieben, wie mit Hilfe des Oxalatverfahrens und anschließender Permanganat-Titration der Ca-Nachweis in Lebensmitteln mit ausreichender Genauigkeit durchgeführt werden kann. Der Einfluß verschiedener Konzentrationen der Matrixelemente P, Mg und Fe wird untersucht. Die relative Standardabweichung der gefundenen Resultate beträgt 0,3%. Die vorgegebene Konzentration des untersuchten Elements in Gegenwart von P, Mg und Fe wird mit einer Bestimmungsgenauigkeit von ±0,5% wiedergefunden. 相似文献
213.
Peter Minkowski 《Nuclear Physics B》1980,174(1):258-268
The color bond structure of a quark-antiquark system is extended, in the long-range approximation, self-consistently to the baryonic three-quark bond structure for SU(3)c and generally to the N-quark bond structure for SU(N)c. The universal (N-independent) mass square eigenvalues for massless quarks are . 相似文献
214.
Prof. Dr. Edmund Hlawka 《Monatshefte für Mathematik》1980,89(1):19-44
A new proof of a theorem of W. Neiss is given that the rays of the Quadratwurzelschnecke are uniformly distributed mod 2 . The exact order of the discrepancy of the sequence is determined. Multidimensional generalizations of this sequence are also considered. It is shown that the Quadratwurzelschnecke is something like a roulette.
Mit 2 Abbildungen
Herrn Prof. R. M. Redheffer in Freundschaft zum 60. Geburtstag gewidmet 相似文献
Mit 2 Abbildungen
Herrn Prof. R. M. Redheffer in Freundschaft zum 60. Geburtstag gewidmet 相似文献
215.
Dr. Lisa Hefendehl-Hebeker 《Monatshefte für Mathematik》1980,90(3):219-228
Motivated by an investigation ofKuz'min [2], in this note we introduce a topology on the set
of nonassociative algebras of a fixed dimensionr< over a local fieldF. We obtain a space, which is notT
1. If the trivial algebra
is removed, the remaining subspace is quasicompact. The space is homeomoprhic to the group of square classes ofF
*; forr3 the space is notT
1. The set of division algebras is open in. 相似文献
216.
Dr. Frank Piefke 《Monatshefte für Mathematik》1980,89(1):45-56
We continue our investigations started in a paper with the same title. The -length of a curve defined in this paper can be written as an integral along the curve. Furthermore, we determine necessary and sufficient conditions for the existence of a measure of orientated lines which generates a given non-symmetric pseudo-metric.
Herrn Prof. Dr. H.-J. Kanold zum 65. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. H.-J. Kanold zum 65. Geburtstag gewidmet 相似文献
217.
In this paper a new notion of uniform distribution of double sequences is introduced. In the most elementary case a double sequence (xmn)m, nN is called uniformly distributed in this sense if all finite matrices of equal size appear with the same frequency as submatrices of the infinite matrix (xmn). Some special double sequences with such a distribution property are studied and metric theorems are proved. 相似文献
218.
Dr. H. G. Kopetzky 《Monatshefte für Mathematik》1977,84(3):213-217
Arithmetic formulae and an asymptotic expression for the order of magnitude of the arithmetic function
ged (s, n) and of a generalisation of it are derived. 相似文献
219.
Prof. Dr. Alexander Aigner 《Monatshefte für Mathematik》1977,83(2):89-91
It is shown by a simple induction that any square-free natural number is the square-free kernel of Euler's -function of infinitely many natural numbers. Furthermore every square-free natural number >1 is the square-free kernel of Euler's -function of infinitely many square-numbers. 相似文献
220.
Dr. Moritz Armsen 《manuscripta mathematica》1977,20(3):245-253
The classical Gauss-Bonnet formula has the form I(gij)=2, where I(gij) represents a sum of three terms each of which depends on the metric tensor gij. It is shown that the first variation I of I(gij) with respect to the metric gij vanishes and that for the Euclidean metric ij we have I(ij)=2. From this the formula I(gij)=2 follows. In the process, explicit expressions are obtained for the first variation of each of the three terms which comprise I(gij). Furthermore, a general expression for the first variation of a multiple integral whose integrand is a scalar density depending on the metric tensor gij and its derivatives up to the second order is obtained with the aid of results of Rund [1]. 相似文献