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101.
It is proved that the even-order equationy
(2n)
+p(t)y=0 is (n,n) oscillatory at if
相似文献
102.
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
103.
In the framework of the Nilsson model the calculations of the so called shape factor for the first forbidden
– transitions 5/2+
241Pu 5/2–
241Am and 7/2+
177Lu 7/2–
177Hf are carried out. The dependence on the Nilsson potential parameters is studied. It turns out that for the transitions considered the calculated shape factor depends linearly on the electron energy and its slope is 10–3 per 20 keV. This can affect the analysis of electron spectra if the endpoint energy is sufficiently large. 相似文献
104.
M. Petráš 《Czechoslovak Journal of Physics》1995,45(6):455-464
Dirac's and Proca's equations are unified in the sense that the algebras of Dirac -matrices and Duffin-Kemmer-matrices are shown to furnish two distinct matrix representations of the Lie algebra of the SO(3,3)-group. This fact is then interpreted as evidence for the classical picture of particles described by the above-mentioned equations to be a relativistic top. It is also argued that the shape of the top is rod-like. 相似文献
105.
Individual extraction constants of some dicarbollylcobaltate anions in the water-nitrobenzene system
E. Makrlík J. Rais K. Baše J. Plešek P. Vaňura 《Journal of Radioanalytical and Nuclear Chemistry》1995,198(2):359-365
Individual extraction constants of nine dicarbollylcobaltate anions in the two-phase water-nitrobenzene system were determined radiometrically assuming that the changes of Gibbs energy of the transfer of the tetraphenylarsonium cation, Ph4As+, and of the tetraphenylborate anion, BPh
4
–
, from the aqueous into the nitrobenzene phase are equal. The constants obtained by this method were correlated with Hansch's constants of hydrophobity. 相似文献
106.
A. Baranowski M. Dębowska K. Jerie J. Rudzińska-Girulska Z. Paweŀka R. T. Sikorski 《Journal of Radioanalytical and Nuclear Chemistry》1995,190(2):463-467
Results of angular correlation of annihilation radiation (ACAR) and positron annihilation lifetime (PAL) measurements are presented for five styrene copolymers: poly(co-styrene-phenylmaleimide) and its three derivatives with chlorine as well as for one with the OH group substituted at the benzene ring. It occurs that the chlorine substituted at three different positions at the benzene ring poly(co-styrene-o (or-m,-p)-chlorophenylmaleimide) inhibits the formation of the positronium to different extent. The greatest effect is observed in case of the chlorine atom substituted at the benzene ring at the ortho-position towards the nitrogen atom. The two long lifetimes (3 and 4) observed in the lifetime spectra are connected with the bimodal distributions of the free volume radius in the samples. 相似文献
107.
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
108.
Christoph Meingast Frank Gugenberger Georg Roth Miro Haluška Hans Kuzmany 《Zeitschrift für Physik B Condensed Matter》1994,95(1):67-71
The thermal expansion of vapor-grownC
70 single crystals ahs been investigated using high-resolution capacitance dilatometry from 5–380 K. Measurements were made both parallel and perpendicular to the hexagonalc-axis. Three first-order phase transitions which we associate with the consecutive disordering of theC
70 molecules are observed upon heating at 280 K (long-axis spinning), 300 K (long-axis precession) and 355 K (quasi-free rotation), respectively. The highest-temperature transition exhibits a very large (50 K) thermal hysteresis. Powder and single-crystal X-ray diffraction show that the crystals are predominantly hexagonal-close-packed (HCP) with an idealc/a1.63 above 360 K andc/a1.84 at 295 K. 相似文献
109.
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
110.
A. Brablec J. Janča V. Kapička D. Trunec Yu. Chutov V. Pikozh 《Czechoslovak Journal of Physics》1996,46(6):587-594
An expansion of finite plasma clots into the background neutral gas is studied numerically. The presented model includes the quasineutrality violation as well as the interpenetration of plasma and neutral gas at the boundary of the plasma. We estimate the region of plasma parameters where the model is correct. Space distributions of main plasma parameters, cooling of electrons and the process of inter-penetration of the plasma and the neutral gas are analysed as well as an empiric formula for electron temperature is found. Finally, it is shown that the most intensive plasma-gas inter-penetration occurs in the case where the initial plasma and gas densities are the same. 相似文献
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