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41.
Mihály Molnár László Palcsu István Futó Éva Svingor Zoltán Major Mihály Veres Péter Ormai István Barnabás 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):745-750
To obtain reliable estimates of the quantities and rates of the gas production in L/ILW a series of measurements was carried
in the last 7 years in Hungary. The typical gas production rates were 0.05–0.2 STP litre gas/day for CO2 and CH4 generation, and less for H2. No explosive gas mixture was indicated in the L/ILW drums during the investigated storage period. Compositions of headspace
gases in closed L/ILW vaults were in agreement with gas generation processes observed in L/ILW drums. The stable carbon isotope
measurements show that the main source of the CO2 gas is the degradation of organic matter and indicates microbial degradation processes as the main sources of CH4. Typical tritium activity concentrations were <10 Bq/l gas in the drums and <1,000 Bq/l gas in the vaults. Typical 14C activity values of the headspace gases were <2.0 Bq/l gas in the drums and <1,000 Bq/l gas in the vaults. 相似文献
42.
Imre Bucsi Szabolcs Cserényi Károly Felf?ldi Mihály Bartók 《Reaction Kinetics and Catalysis Letters》2006,87(2):281-289
Summary We synthesized C9-O-silyl ethers of cinchonidine and dihydrocinchonidine (1-8), seven of which have not been known before. The structures of the compounds were verified by ESI-ion-trap MS and 1H-NMR. Fragmentation of silyl ethers containing Si-phenyl bonds was studied for the first time. The compounds obtained will
be utilized as chiral catalysts of certain asymmetric syntheses.</o:p> 相似文献
43.
The paper is devoted to the study of wave propagation through materials with internal state variables under two main assumptions: finite speed of propagation and symmetry of acceleration waves. Additional constitutive assumptions are also used: heat flux does not depend on the temperature gradient and the time-derivatives of internal state variables are linear functions of the temperature gradient. Under all these hypotheses, in the neighborhood of a strong equilibrium state, one finds four real and symmetric possible acceleration waves, at least two of them being coupled waves, and heat flux results an internal state variable. All these results are obtained in the general three-dimensional case. As an illustration, the isotropic linear theory is considered, where both acceleration and shock waves are treated. 相似文献
44.
Balázsik K Szori K Szollosi G Bartók M 《Chemical communications (Cambridge, England)》2011,47(5):1551-1552
In competitive racemic hydrogenation of methyl benzoylformate (MBF) + ethyl pyruvate (EP) binary mixture over Pt/Al(2)O(3): k(MBF) > k(EP), but in competitive enantioselective hydrogenation k(MBF) < k(EP); the phenomenon verified for the first time is dependent on the adsorption strength of the surface complexes of various compositions (MBF-Pt, EP-Pt, MBF-CD-Pt, EP-CD-Pt, CD = cinchonidine). 相似文献
45.
László Mihályffy 《Central European Journal of Operations Research》2011,19(2):225-238
Calibration is a common technique of data processing in survey sampling. Although convex programming would be an obvious tool
for this purpose, usually other methods are used in the practice of statistical institutes. A comparison of those methods
and convex programming is reported on in this paper. 相似文献
46.
I. Ursu I. Apostol D. Bǎrbulescu I.N. Mihǎilescu M. Moldovan A.M. Prokhorov V.P. Ageev A.A. Gorbunov V.I. Konov 《Optics Communications》1981,39(3):180-185
The analysis of some new experimental data has proved that the evaporation of a stainless steel target in vacuum under the action of powerful TE-CO2 microsecond pulsed laser radiation is initiated on the initial spike or not at all. The minimum “tail” duration to get evaporation was deduced as a function of the temporal pulse shape characteristics and the metal thermophysical properties. The vaporisation process was accompanied by nonequilibrium heating of vapour clouds leading to the target surface shielding. Two self-regulated evolutions were recognised which were attributed to the intense vaporisation and the target evaporation by the UV plasma emitted radiation, respectively. 相似文献
47.
The P-V-T relations of high pressure polyethylene free of additives have been studied in a modified universal testing machine. These polymers show a rapid compression at the melting point of the crystalline phase. 相似文献
48.
I. Ursu R. Alexandrescu V. Drăgănescu C. Grigoriu I. N. Mihăilescu I. Morjan A. M. Prokhorov N. V. Karlov A. S. Lagutchev A. N. Orlov Yu. N. Petrov 《Applied physics. B, Lasers and optics》1988,47(1):61-65
New experimental results are reported pointing to the possibility of a laser control of the resonant gases transit through capillaries in the Knudsen and intermediate regimes. 相似文献
49.
Riemann and Goursat step data problems for extensible nonlinear elastic strings are solved in the class of regulated functions. In the first paragraph, the solution to the simplest initial and boundary value problem, i.e., Goursat problem in strains, is constructed. This solution points out four vector-valued functions of a vector variable, which are the tools used in solving the Goursat problem in velocity and the Riemann problem. 相似文献
50.
DC conductivity and thermoelectric power measurements are presented on the organic charge transfer salt TTT-I1.6. It is argued that the metallic low temperature behaviour srises from the joint influence of a finite interchain bandwidth and weak disorder. 相似文献