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11.
12.
M. Rotter B. Sedlák J. Englich P. Čížek M. Finger P. Malinský V. N. Pavlov 《Hyperfine Interactions》1987,34(1-4):303-306
The results of NMR/ON measurements on56'57'60Co isotopes in iron are presented. To avoid the uncertainties caused by local demagnetizing field inhomogenities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factor ratios
57/
60 = 1.805 (20),
60/
56 = 0.761 (20),
56/
57 = 0.726 (20) and hyperfine anomalies5660 = -0.036 (10),60
57 = 0.017 (10) and5756 = 0.018 (10) have been calculated from the experimental results. 相似文献
13.
O. Čermáková 《Czechoslovak Journal of Physics》1986,36(9):1058-1062
This contribution presents birefringence spectra for orthorhombic YAlO3Ce single crystal in the region 2–5 eV. The spectra were measured by means of a reflection method of null ellipsometry and were compared with spectra of YAlO3:Nd determined from values measured in the region of lower energies (1·1–2·2 eV). We have found that there are differences between the spectra of YAlO3Nd and YAlO3:Ce which are most pronounced in thea-axis direction.The author is most grateful to Ing. . Viovský CSc. for helpful discussions during the course of this work and to Monokrystaly Turnov for preparation of the samples. 相似文献
14.
M. Rotter B. Sedlák J. Englich P. Čížek M. Finger P. Malinský 《Czechoslovak Journal of Physics》1986,36(11):1331-1335
The results of NMR/ON measurements on56,57,60Co isotopes in iron are presented in the paper. To avoid the uncertainties caused by local demagnetizing field inhomogeneities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factors ratios
57/
60=1·805(20),
60/
56 = 0·761(20),
56/
57 = 0·726(20) and hyperfme anomalies56
60 = –0·036(10),60
57 = 0·017(10) and57
56 = 0·018(10) have been calculated from the experimental results.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research. 相似文献
15.
Bimetallic ruthenium-tin catalysts were prepared using the sol-gel method and the method of carrier impregnation. Two different
procedures were used for their reduction — reduction in hydrogen atmosphere under an increased temperature, and reduction
using an aqueous solution of sodium borohydride. Hydrogenation of 3-phenylpropenal (cinnamaldehyde) in tetrahydrofuran at
433 K and the total pressure 7 MPa was used as the model reaction for comparing the catalytic properties of the prepared catalysts.
It was demonstrated that a tin addition notably affected catalytic properties of ruthenium in the sense of a selectivity increment
related to the production of an unsaturated alcohol. 相似文献
16.
Urška L. Štangar Urh Černigoj Polonca Trebše Ksenija Maver Silvia Gross 《Monatshefte für Chemie / Chemical Monthly》2006,137(5):647-655
Summary. Transparent TiO2 films with a high photodegradation activity towards an azo dye in aqueous solution were prepared by sol–gel processing. Films
on soda–lime glass supports protected with a thin silica barrier layer exhibited better crystallization and monodisperse nanoparticles,
higher absorption of light below 370 nm, and higher photocatalytic activity than those films deposited on bare glass supports
proving the detrimental effect of interdiffused sodium ions on the development of the anatase nanostructure. The effect of
substrate was more pronounced in thinner films (300 nm) than in thicker ones (1200 nm), which were achieved by adding a template
(i.e. Pluronic F127) to the sol. 相似文献
17.
Zusammenfassung Mit Hilfe von Gemischen wurden die formalen Redoxpotentials einiger einfacher Aminophenoxazone-(3) und 2-substituierter Gallocyaninmethylesterderivate (Prune) mit den Substituenten — NH-C6H4X [X = H, CH3, OCH3, OH, NH2, N(C2H5)2] in 50%iger Äthanollösung mit einer konstanten Ionenstärke in der Abhängigkeit vom pu bei 25° C gemessen.Die auf pH=0 extrapolierten Potentiale stehen mit den Hammetschen -Konstanten in guter Korrelation.
Wir danken Herrn Ing.Z. Stránský C. Sc. für wertvolle Erinnerungen bei der Interpretation der Ergebnisse. 相似文献
Summary With the aid of mixtures the formal redox potentials of several simple aminophenoxazones-(3) and 2-substituted gallocyaninmethylester derivates (Prunes) with the substituents -NH-C6H4X [X = H, CH3, OCH3, OH, NH2, N(C2H5)2] were measured in 50% ethanol solution with a constant ionic strength with respect to the dependence of pn at 25° C. The potentials extrapolated to pn = 0 are in good correlation with the Hammet -constants.
Wir danken Herrn Ing.Z. Stránský C. Sc. für wertvolle Erinnerungen bei der Interpretation der Ergebnisse. 相似文献
18.
The title compounds were prepared by dehydrocyclization of corresponding substituted N-nitrosoglycines obtained from isomeric o-, m- and p-aminodiphenyl ether with ethyl bromoacetate and subsequent nitrosation of the intermediate N-arylsubstituted glycines. 相似文献
19.
The reduction of Ni2+ ions at mercury electrodes in acidic perchlorate solutions, at perchlorate concentrations below 0.2 M, is characterized by absence of kinetic control in the preceding step, and by a complex reaction mechanism following the electron transfer. This reaction sequence is known to involve intermetallic compound formation between Ni and Hg and is best described, as shown here, by a parallel second and third order kinetic scheme. Apparent rate coefficients for this kinetic scheme were determined using cyclic chronopotentiometric data and fitting by digital simulation. A linearization test of computed kinetic rate coefficients versus the number of transitions permits quantitative tests of validity of assumptions made. 相似文献
20.
The electronic spectra of tetrathiotetracene (TTT) and of its mono- and dipositive ions have been calculated by the Pariser-Parr-Pople (PPP) method. Furthermore, the band polarizations of the first two bands of TTT have been measured. A reasonable band assignment is given using a new set of PPP parameters based on spectral data of a naphthalene derivative containing similar typical weak S-S bond. Other physical parameters as ionization potential, disproportionation energy, S-S bond length and net π-charges are discussed. 相似文献