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131.
I. B. Plećaš A. D. Perić J. D. Drljača A. M. Kostadinović 《Journal of Radioanalytical and Nuclear Chemistry》1992,157(1):95-104
An optimization of mortar (as matrix), improved with bentonite clay, used for immobilization of radionuclides60Co,137Cs,85Sr and54Mn, is presented. A relatively simple mathematical model is given, which permits minimization of leach rate and permeability and maximization of compressive strength. An optimal solution, based on experimental data, is given. These results will be used for a future Yugoslav radioactive waste storing center. 相似文献
132.
106Ru chloro and nitrosyl-nitrato complexes in sea water were separated into several species by continuous electrophoresis on
a filter paper curtain. Biological uptake experiments were carried out on sea algae Fucus virsoides with fractionated106Ru chloro and nitrosyl-nitrato complex species in sea water. The biological uptake of106Ru chloro complex species was about 8 times higher than the uptake of106Ru nitrosyl-nitrato species. Electrophoretically most mobile electrically positively charged cationic species in both systems
also showed about 8 times higher biological uptake than the most mobile negatively charged anionic species. A close relation
of the biological uptake to the sign of the electrical charge and the electrophoretic mobility of the species is demonstrated.
The results are discussed with respect to possible danger to the biological environment as a consequence of the aging of ruthenium
species in sea water resulting from106Ru waste disposal to the sea from a nuclear reprocessing plant.
On leave of absence from the National Institute of Radiological Sciences, 9-1, 4-chome, Anagawa, Chiba-shi, Japan, on a fellowship
from The Science and Technology Agency of the Japanese Govemment. 相似文献
133.
G. Mekuškiené P. Vainilavičius A. Hetzheim R. Shematovich 《Chemistry of Heterocyclic Compounds》1993,29(5):598-602
The reaction of the hydrazide of 4,6-dimethyl-2-pyrimidinecarboxylic acid with potassium ethylxnthate gave 5-(4,6-dimethyl-2-pyrimidinyl)-1,3,4-oxadiazole-2-thione. The alkylation of this product in an alkaline medium proceeds at the sulfur atom, while the aminomethylation and acylation proceed at the nitrogen atom. The major criterion for the structure of the S- and N-derivatives is the chemical shift of C(2) in the 1,3,4-oxadiazole ring in the 13C NMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 700–705, May, 1993. 相似文献
134.
Zusammenfassung 1,3-Dimethyl-4,5-diaminouracil (DAL) hat sich als sehr empfindliches Reagens zum selektiven Nachweis von Co2+-Ionen im stark alkalischen Medium einer Phosphatpufferlösung (pH=11,20) erwiesen. Es wurden vier Additionsverbindungen von DAL mit den Zentralatomen Cd(II), Pd(II), Ni(II) und Co(II) im Verhältnis Me DAL=1 2 hergestellt. Spektrophotometrische Untersuchungen weisen darauf hin, daß bei pH 6 bis 7 eine Komplexverbindung im Verhältnis CoDAL=12 gebildet wird.
Summary 1,3-dimethyl-4,5-diaminouracil (DAL) has been found to be a very sensitive reagent for the selective detection of Co2+ ions in strong alkaline medium of a phosphate buffer solution (pH=11.20). Four addition compounds of DAL with the central atoms Cd(II), Pd(II), Ni(II) and Co(II) with the ratio MeDal=12 have been prepared. Spectrophotometric studies indicate that at pH=6–7, complex compound is produced with the ratio CoDAL=12.相似文献
135.
Changes of the rheological properties of hyaluronic acid (sodium-magnesium salt) solutions after exposure to UV radiation
indicate a vigorous decrease in their viscosity, but its still strong shear rate dependence. Whereas the presence of the singlet
oxygen sensitizer (anthracene-1-sulphonic acid) brings about a loss of shear dependence; the studied solutions show newtonian
behavior. 相似文献
136.
A. Z. Dubničková S. Dubnička M. E. Biagini A. Castro 《Czechoslovak Journal of Physics》1991,41(12):1177-1188
The behaviour of the -hyperon electric and magnetic form factors is predicted within the modified three resonance ((783), (1020), (1680)) vector-meson dominance (VMD) model with correct analytic properties and the asymptotic behaviour predestinated by the quark model for baryons. The resonance couplings to are evaluated from the known couplings to nucleons by utilizing theSU(3) symmetry and normalization conditions for Dirac and Pauli form factors. The masses and widths of the considered vector mesons are fixed at the world averaged values. The optimal position of the effective inelastic threshold, common for Dirac and Pauli form factors, is determined from the fit of the only existing Orsay DM2 point on the
cross section att=5·693 GeV2. The mean square charge and magnetic radii of the -hyperon are found to be r
E
2
=0·018 F2 and r
M
2
=–0·027 F2, respectively.The authors are very much indebted to Prof. R. Baldini-Ferroli for calling their attention to the problem of -hyperon e.m. ff 's in connection with the FENICE experiment. 相似文献
137.
Jan Kučera 《Czechoslovak Journal of Physics》1991,41(9):825-846
Three parts of the paper [Czech. J. Phys.41 (1991) 620,7 are focused on the Landauer-Büttiker approach to the study of transport in two-dimensional electron systems, with particular attention to the influence of an external magnetic field. In the previous parts the Landauer formalism was generalized for two-dimensional systems in quantizing magnetic fields. In the present part we applied the formalism to an analysis of magnetoresistance measurements. The two-dimensional electron gas preserved in the non-dissipative quantum Hall regime acts as the ideal leads necessary in the Landauer-Büttiker approach. The voltage, applied to the gate, forms a scattering region in the gated part of the sample, in between of its undisturbed parts (ideal leads). The dependence of the resistance on the gate voltage and the number of available channels within the ideal leads are discussed.The author wishes to thank to Professor P. Steda for cooperation and to Professor L. Smrka for his encouragement and support. Dr. R. J. Haug should be acknowledged for providing his experimental results. 相似文献
138.
The geometro-stochastic quantization of a gauge theory based on the (4,1)-de Sitter group is presented. The theory contains an intrinsic elementary length parameter R of geometric origin taken to be of a size typical for hadron physics. Use is made of a soldered Hilbert bundle over curved spacetime carrying a phase space representation of SO(4, 1) with the Lorentz subgroup related to a vierbein formulation of gravitation. The typical fiber of is a resolution kernel Hilbert space
constructed in terms of generalized coherent states
related to the principal series of unitary irreducible representations of SO(4, 1), namely de Sitter horospherical waves for spinless particles characterized by the parameter . The framework is, finally, extended to a quantum field-theoretical formalism by using bundles with Fock space fibers constructed from
.Supported in part by NSERC Research Grant No. A5206. 相似文献
139.
Differential calculus on quantized simple lie groups 总被引:1,自引:0,他引:1
Branislav Jurčo 《Letters in Mathematical Physics》1991,22(3):177-186
Differential calculi, generalizations of Woronowicz's four-dimensional calculus on SU
q
(2), are introduced for quantized classical simple Lie groups in a constructive way. For this purpose, the approach of Faddeev and his collaborators to quantum groups was used. An equivalence of Woronowicz's enveloping algebra generated by the dual space to the left-invariant differential forms and the corresponding quantized universal enveloping algebra, is obtained for our differential calculi. Real forms for q are also discussed. 相似文献
140.
Dielectric properties of plasma polymerized PVCa and composite PVCa:Au films had been analyzed in the frequency range from 10 to 105 Hz. In order to explain experimental data obtained the modification of Maxwell-Garnett and Bruggeman self-consistent models for the case of three-component composite has been done. The theoretical analysis performed allows to determine peculiarities of dielectric behavior of a three-component system, as well as to disclose the procedure of evaluation of third-component parameters. Results of this analysis are in agreement with experimental ones. 相似文献