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3.
G. Ch. Shushkevich 《Technical Physics》1998,43(7):743-748
The electrostatic problem for a thin, unclosed spherical shell and a torus is reduced to paired summation equations in the
Legendre polynomials by means of formulas relating the spherical and toroidal harmonic functions. The paired equations are
transformed to a Fredholm integral equation of the second kind. Formulas are obtained for computing the charges of the conductors
in the form of a series in a small parameter. The capacitance is computed for certain geometrical parameters of the conductors.
Zh. Tekh. Fiz. 68, 1–6 (July 1998) 相似文献
4.
Julia K Pruns Jens-Peter Vietzke Manfred Strassner Claudius Rapp Ulrich Hintze Wilfried A K?nig 《Rapid communications in mass spectrometry : RCM》2002,16(3):208-211
A new solvent-free sample preparation method using silver trifluoroacetate (AgTFA) was developed for the analysis of low molecular weight paraffins and microcrystalline waxes by laser desorption/ionization time-of-flight mass spectrometry (LDI-TOFMS). Experiments show that spectral quality can be enhanced by dispersing AgTFA directly in liquid paraffins without the use of additional solvents. This preparation mixture is applied directly to the MALDI probe. Solid waxes could be examined by melting prior to analysis. The method also provides sufficiently reproducible spectra that peak area ratios between mono- and bicyclic alkane peaks indicated variations in the cycloalkane content of paraffin samples. Dehydrogenation of hydrocarbons observed during the desorption/ionization process was studied by analysis of alkane standards. 相似文献
5.
The versatile behavior of a trihydrazidophosphoradamantane allowing the synthesis of a variety of neutral, mono- or di-cationic water-soluble molecules of potential interest for biphasic catalysis is reported. 相似文献
6.
In this paper we construct an example of a word metric on an infinite cyclic subgroup. This example shows that subexponential
distortion does not obstruct non-trivial growth of connected radii. This answers a question of Gromov [6]. The constructed
metric has other pathological properies. Specifically, its asymptotic cone depends on the choice of ultrafilter and scaling
sequence.
The work has been partially supported by the Swiss National Science Foundation. 相似文献
7.
Two methods for multi-element preconcentration from copper by reductive matrix precipitation are presented. In systematic investigations on the coprecipitation behaviour of Ag, Al, Au, Bi, Cd, Co, Cr, Fe, Ga, In, Mn, Mo, NJ, Pb, Sb, Se, Sn, Te and Zn during precipitation of the copper matrix as Cu2O or CuSCN, the separation parameters were optimized. By combination with a hexamethyleneammonium hexamethylenedithiocarbamate collector precipitation, a concentration of 8 elements (Cu2O precipitation) or 13 elements (CuSCN precipitation) in a small volume was achieved. The limits of detection of the procedures are, depending on the element, 0.1–5 μg g?1 for flame atomic absorption spectrometry (AAS) and 0.01–0.1 μg g?1 for graphite furnace AAS. The relative standard deviations are about 3%. The analytical performance of the procedures is compared with that of an electrolytic copper separation. 相似文献
8.
We build a metric space which is homeomorphic to a Cantor set but cannot be realized as the attractor of an iterated function system. We give also an example of a Cantor set K in R3 such that every homeomorphism f of R3 which preserves K coincides with the identity on K. 相似文献
9.
Milan Medved? 《Journal of Mathematical Analysis and Applications》2002,267(2):643-650
A criterion for the nonexplosion of solutions to semilinear evolution equations on Banach spaces is proved. The result is obtained by applying a modification of the Bihari type inequality to the case of a weakly singular nonlinear integral inequality. 相似文献
10.
A. M. Lyudchik A. N. Krasovskii L. N. Turyshev L. Ch. Neverovich 《Journal of Applied Spectroscopy》1991,55(3):928-933
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 3, pp. 472–477, September, 1991. 相似文献