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251.
J. Hladký S. NĚmeček M. Novák A. Prokeš J. Votruba K. -F. Albrecht A. Meyer M. Sachwitz B. N. Guskov V. G. Krivokhizhin M. F. Likhachev I. A. Savin G. Vesztergombi 《Czechoslovak Journal of Physics》1977,27(11):1210-1218
Results of the first elastic K
S
o
regeneration experiment on carbon, using magnetic spark chamber spectrometer, are presented in the beam momentum interval 10p50 GeV/c. The d ifferentia cross section d/dt is reconstructed in the range 0·0025–t0·02 (GeV/c)2 and its slopeB is found to be momentum independent with an average valueB=(65±11) (GeV/c)–2. The results are in agreement with the calculations using the coherent production model. 相似文献
252.
The Galerkin method of solution of integral equations using splines is proposed. This method is applied to the Lippmann-Schwinger equation. Bound state energies and correspondingt-matrices are calculated for various potentials. This method can also be applied to reduce the Faddeev equation to the one-dimensional ones.The authors are grateful to Doc. J.Kvasnica for number of useful discussions and to M.erný for help with numerical calculations. 相似文献
253.
V. Babický K. Koláček J. Ullschmied N. I. Malych 《Czechoslovak Journal of Physics》1977,27(10):1125-1128
A laser interferometer, operating at the wavelength =0·337 mm suitable for the plasma density measurements in the range 1019–1022 m–3 as well as a simple construction of the HCN laser are described.The authors wish to thank Dr. P.unka for fruitful discussions and Dr. J.Musil for the design and construction of the detector. 相似文献
254.
D. Šokčević Z. Lenac R. Brako M. Šunjić 《Zeitschrift für Physik B Condensed Matter》1977,28(4):273-281
We develop a theory of low energy electron loss spectroscopy of vibrational modes of molecules adsorbed on metal surfaces. Differential and total cross sections are calculated in the Distorted Wave Born Approximation, assuming i) strong elastic scattering on the metal surface, ii) direct electron-molecule interaction via the electric dipole field associated with the molecular vibration. The angular distributions are calculated and discussed for molecules adsorbed at various distances above the metal surface and for several electron energies and impact angles. The influence of electronic screening of dipolar oscillations is discussed and the consequences of the classical induced image dipoles are explored. It is shown that the metal surface selection rule known in IR spectroscopy is only approximately valid in electron scattering. Finally, we give numerical estimates of the inelastic scattering cross sections for the stretching vibrations of CO molecule adsorbed on transition metal surfaces, in reasonable agreement with experiments. 相似文献
255.
Jozef Chomič Ján Skoršepa Juraj Černák Alexander Hudák 《Monatshefte für Chemie / Chemical Monthly》1982,113(6-7):713-714
The preparation, identification and some properties of three new clathrate compounds Cd(mea)[Pd(CN)4] · 2C6H6, Cd(mea)2[Pd(CN)4] · C4H4S and Cd(mea)2[Pd(CN)4] · C4H4NH (mea = HO-CH2-CH2-NH2) are described. 相似文献
256.
L. Mrkvičková 《Colloid and polymer science》1989,267(1):28-33
The structure of supermolecular formations and the interparticle interaction in aqueous poly(vinyl alcohol) solutions aging at different concentrations were investigated. Integral light scattering was used to determine the single particle scattering functionP(K), the structure functionS(K), and hence the radial distribution functiong(r). Nonrandom arrangement of the supermolecular formations in solutions under study is much less intensive than that of particles in polymer latices. 相似文献
257.
Summary A general definition of reaction graphs is presented. For a pair of isomeric molecular graphs
and
, related by a chemical transformation
, the reaction graph
is determined using a maximal common subgraph defined for vertex mapping
. A binary operation defined for graphs constructed over the same vertex set enables us to decompose the reaction graph
into the sum of prototype reaction graphs. A decomposition of an overall reaction graph can be advantageously used for the construction of a reaction network. An oriented path in this network beginning at
and ending at
corresponds to a breakdown of the transformation
into a sequence of intermediates. 相似文献
258.
K. Markova D. Minčev D. Rustschev O. Atanasov 《Journal of Thermal Analysis and Calorimetry》1988,34(1):65-69
The thermal behaviour of three gagates (Bulgaria) was investigated by DTA and TG. The characteristic endo- and exoeffects and the sequence of the thermal stabilities are established.
Zusammenfassung Das thermochemische Verhalten von drei Gagaten (Bulgarien) wurde mittels DTA und TG untersucht. Die charakteristischen endo- und exothermen Effekte und die Reihenfolge der thermischen Stabilitäten wurden ermittelt.
(). - .相似文献
259.
The quantitative electrochemical generation of bromine at a platinum electrode in acetic acid is described. Coulometric methods for the determination of hydroquinone and 2-methylhydroquinone are reported. The best results are obtained with 0.7–1.1 M potassium acetate solutions as supporting electrolyte, and biamperometric end-point detection. The effects of water and acetic anhydride on the accuracy of titrations are discussed. Determination of the formal redox potential of the Br2/Br- system in a 0.9 M potassium acetate solution in acetic acid showed that bromide is oxidized directly to bromine at a platinum electrode with 100% current efficiency. 相似文献
260.
Olefins are converted into allylic acetates by treatment in acetic acid with a catalytic amount of palladium bis(trifluoroacetate) and one equivalent of benzoquinone as oxidant. The reaction is selective for oxidation of a terminal methyl group of geranylacetone. 相似文献