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81.
Vladimír Olejček 《International Journal of Theoretical Physics》1995,34(8):1643-1646
The q--algebra, i.e., the system of sets closed under complementation, countable disjoint unions, and containing the empty set, generated by the system of open balls coincides with the -field of Borel sets inR
sun forn=1,2, and 3. A first step to extend the proof forn=4, 5, 6, and 7 is indicated. 相似文献
82.
I. Muzyčenková V. Kellnerová M. Koneracká P. Kopčanský M. Antalík J. Ďurišin 《Czechoslovak Journal of Physics》1995,45(9):727-734
The encapsulation of fine magnetite particles of 10 nm size and marker ANS within asolectin vesicles has been made by sonication of the mixture in water. For the proof of encapsulation of magnetite in vesicles the electron microscope and spectrofluoriphotometer technique were used. The theory for the calculation of the magnetic force acting on the system consisted of non-capsulated magnetic particles dispersed in water and magnetic vesicles was developed.This work was supported by the Slovak Academy of Sciences within the framework of Project GAV No. 1361. 相似文献
83.
In this paper large-scale properties of developed magnetohydrodynamic turbulence have been investigated by using double expansion method in the frame of quantum field renormalization group. It has been shown that universal kinetic scaling regime exists, but the double expansion in general leads to qualitatively different results than those provided by the usual -expansion treatment.This work was supported by Slovak Grant Agency for Science. 相似文献
84.
The radionuclides54Mn,60Co,90Sr,95Nb,95Zr,103Ru,106Ru,125Sb,131I,134Cs,137Cs,140Ba,144Ce,226Ra and228Ac have been studied in the Sava River environment since the Chernobyl accident in 1986. The measured periphyton concentration ratios (CR) for each radionuclide were correlated with the measured sediment distribution coefficients (Kd) for that radionuclide. The Kd-CR relationships obtained were defined by the equation ln Kd=–0.5 ln CR +7.4. These Kd-CR relationships were assumed to be referable to the Sava River ecosystem and were used to predict the missing soil Kd values and/or the missing CR values for the wide range of radionuclides, respectively. Moreover, the Kd-CR relationship characteristic for the Sava River ecosystem was compared with the Kd-CR relationship proposed by Baes1 and by Shepard2. The characterization of the partition coefficients in the Sava River environment and understanding of the mechanisms affecting radionuclide retardation and bioaccumulation are required for the planning of radioactive waste depositories in the area. 相似文献
85.
The Boussinesq approximation, where the viscosity depends polynomially on the shear rate, finds more and more frequent use in geological practice. In the paper, this modified Boussinesq approximation is investigated as a dynamical system for which the existence of a global attractor is proved. Finally, a new criterion for estimating the fractal dimension of invariant sets is formulated and its application to the problem under consideration is illustrated. 相似文献
86.
We give a necessary and sufficient condition for a Bell-type inequality to hold in a horizontal sum of finitely many finite Boolean algebras. 相似文献
87.
V. Hnatowicz J. Kvítek V. Švorčík V. Rybka V. Popok 《Czechoslovak Journal of Physics》1994,44(6):621-627
Samples of polyethylene (PE) loaded with carbon black up to 8 wt.% and implanted with 150 keV Sb+ ions to the doses from 2×1013–2×1015 cm–2 were studied using standard Rutherford Back Scattering (RBS) technique. On the PE samples implanted to the doses above 2×1014 cm–2, a considerable surface carbonization is observed. The measured parameters of the Sb depth profile are compared with theoretical TRIM estimations. The projected range is by 25% lower than the theoretical one and the range straggling is about twice of that predicted. The differences are explained by stepwise polymer degradation during the ion bombardment. Strong oxidation of the ion implanted polymers is also observed. The oxygen depth profiles from the sample surface up to the depth comparable with Sb+ ion range evolve from nearly uniform one for low ion doses to highly non-uniform one for doses above 1×1015 cm–2. The total oxygen content in the sample surface layer 300 nm thick reaches a maximum for the doses of (1–2)×1014 cm–2.On leave from Belorussian State University, 220050 Minsk, Belarus.The authors thank the member of electrostatic accelerator group at INP for help during RBS measurements. The work was partly (V.H. and J.K.) supported by the Internal Grant Agency of the Academy of Sciences of Czech Republic under the grant No. 14805 and by the Internal Grant Agency of the Ministry of Education of Czech Republic under the grant No. 1002 (V.., V.R., V.H. and J.K.). In the final stage, the work was also supported by the Grant Agency of Czech Republic under the grant No. 202/93/0121. 相似文献
88.
Results of the57Fe Mössbauer spectroscopy of greigite from the greigite-rich horizon of the middle part of the miocene series (Sokolov Basin, North Bohemia) are reported. From the room-temperature transmission spectra of the powdered samples magnetically separated from claystones, the Mössbauer analyses were performed. Relative abundances of various magnetic and non-magnetic Fe2+ and Fe3+ species led to the identification of the two magnetic iron sites in greigite in accordance with its spinel structure having mutually near effective magnetic inductions of 32.1 and 31.3 T, respectively. In addition, three pyrrhotite and two magnetite magnetic sites plus probably two pyrite and/or arsenopyrite iron positions were identified, of which some have been reported in the literature as the greigite iron contributions. 相似文献
89.
In the framework of noncommutative geometry we describe spinor fields with nonvanishing winding number on a truncated (fuzzy) sphere. The corresponding field theory actions conserve all basic symmetries of the standard commutative version (space isometries and global chiral symmetry), but due to the noncommutativity of the space the fields are regularized and they contain only a finite number of modes.Part of the Project P8916-PHY of the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich. 相似文献
90.
Precise values of energies and widths of low-lying resonances in some rare-gas atom systems (Ar-Ar, Ne-Kr, Ne-Xe) are reported. 相似文献