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1.
On the basis of the general class of solutions of 6D vacuum Einstein equations and using well-known results of the 6D geometric model of electroweak and gravitational interactions, the variations of fundamental physical constants and their influence on the observed red-shift of galaxies are investigated. By considering the interpretation of extra components of the 6D metric as reproducing the properties of matter in the 4D curved space-time, the effective quantities of matter are obtained. In particular, the states of dust and radiation are shown. The corresponding 5D models were also investigated. 相似文献
2.
We study the possibility of defining the (braided) comultiplication for the GL
q
(N)-covariant differential complexes on some quantum spaces. We discover suchdifferential bialgebras (and Hopf algebras) on the bosonic and fermionic quantum hyperplanes (with additive coproduct) and on the braided matrix algebra BM
q
(N) with both multiplicative and additive coproducts. The latter case is related (forN = 2) to theq-Minkowski space andq-Poincaré algebra. 相似文献
3.
A. A. Berezhnoy F. L. Vladimirov I. Yu. Grodetskii Yu. L. Korzinin V. I. Sukhanov 《Optics and Spectroscopy》2002,93(5):777-780
The possibility of usage of the spontaneous electrooptical (EO) effect in strontium barium niobate (SBN) crystals for the creation of controlled electroholographic elements is studied. It is found that unipolar EO properties of these crystals with respect to switching their spontaneous polarization make it possible to devise field-controlled holographic elements with reversible energy-independent memory for spatial position of an optical beam. 相似文献
4.
A mathematical model is constructed of a nonautonomous dynamic system containing a nonlinear capacitance and possessing a
four-dimensional phase space. A numerical investigation is performed of branching processes and phenomena accompanying variations
in the frequency and amplitude of an external force. The existence of complex dynamic processes that are a combination of
a nonlinear force resonance and a parametric resonance is demonstrated. It is found that both a strange chaotic and a strange
nonchaotic attractor exist in the phase space. It is shown that, in the case of a single-frequency external force, the latter
attractor exhibits the property of roughness. The results of numerical calculations are confirmed by the results of laboratory
experiments. 相似文献
5.
We consider a new model for passive mode locking in a semiconductor laser comprising a set of delay differential equations. Bifurcations leading to the appearance and break-up of the mode-locking regime are studied numerically. 相似文献
6.
Uwe Bandelow Mindaugas Radziunas Andrei Vladimirov Bernd Hüttl Ronald Kaiser 《Optical and Quantum Electronics》2006,38(4-6):495-512
We study both theoretically and experimentally typical operation regimes of 40 GHz monolithic mode-locked lasers. The underlying
Traveling Wave Equation model reveals quantitative agreement for characteristics of the fundamental mode-locking as pulse
width and repetition frequency tuning, as well as qualitative agreement with the experiments for other dynamic regimes. Especially
the appearance of stable harmonic mode-locking at 80 GHz has been predicted theoretically and confirmed by measurements. Furthermore,
we derive and apply a simplified Delay-Differential-Equation model which guides us to a qualitative analysis of bifurcations
responsible for the appearance and the breakup of different mode-locking regimes. Higher harmonics of mode-locking are predicted
by this model as well. 相似文献
7.
V. V. Vladimirov V. N. Gorshkov 《Applied Physics A: Materials Science & Processing》1988,46(2):131-136
In this paper we find the parameters (radii, lengths, velocities) of the jets produced in liquid-metal ion sources. The jet stability with respect to developing sausages (Rayleigh instability) is studied. The Rayleight instability is shown to occur for rather large currents (in long jets). The currents critical for the instability initiation are calculated for Ga and Au sources. The results are in accordance with the experimental data available. In the case of Ga, the accordance is achieved only for the hot jet model (TT
m
, whereT
m
is the melting temperature), when the viscosity is appreciably lower. 相似文献
8.
M. S. Jovanović J. Brborić S. Vladimirov Lj. Šuturkova 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(3):555-560
The partition coefficient (log P) for n-octanol/water system was calculated applying PACO program for various theoretically possible mono and dihalogenated IDA derivatives. Some of the synthesized ligands (SOLCOIODIDA, IODIDA and DIIODIDA) were labeled with the technetium-99m. The biodistribution and influence of bilirubin on their biokinetics were investigated in rats. The correlation between partition coefficients of ligands increase (log P) and better hepatobiliary properties of 99mTc-IDA derivatives was determined. The values of log P increase from 1.16 for SOLCOIODIDA, 3.11 for IODIDA to 3.47 for DIIODIDA. In correlation with these results, biliary excretion decreased for 59% for 99mTc-SOLCOIODIDA and 11% for 99mTc-IODIDA and 99mTc-DIIODIDA under hyperbilirubinemia (3.5 min after injection) and 45%, 11% and 0.38% respectively (15 min after injection). The highest biliary excretion had 99mTc-DIIODIDA (55.4% for 3.5 min). Considering the correlation between hepatobiliary properties and log P, the evaluation of biological properties for various trifluoromethyl mono and dihalogenated IDA derivatives was performed on the basis of the calculated log P in order to synthetize a new radiopharmaceutical for hepatobiliary scintigraphy. 相似文献
9.
Porphyrin and pyrene photoactive cores have been encapsulated within an isolating polymeric shell using an efficient and general strategy based on the use of dendritic initiators for the ring-opening polymerization of epsilon-caprolactone to yield functional core star polymers. The isolation of the core functionalities has been studied using fluorescence quenching and fluorescence resonance energy transfer (FRET) techniques as well as solvatochromic probes. With increasing chain length as well as solvent polarity, enhanced site isolation of the core has been observed. These findings have been correlated to actual molecular dimensions independently measured by pulsed field gradient spin-echo (PGSE) NMR. The developed synthetic methodology offers a rapid route to efficient encapsulation of functional moieties and therefore has potential for the design of new materials. 相似文献
10.
M. S. Jovanovic B. Zmbova D. Zivanov-Stakic S. Vladimirov 《Journal of Radioanalytical and Nuclear Chemistry》1993,171(2):451-456
The interaction of bilirubin and99mTc-HIDA and99mTc-IODIDA has been studied in rats. The mechanism of this interaction has been examined at the level of binding with human serum albumin (HSA) by the in vitro method. Percentage of binding with HSA, and affinity constants for99mTc-IODIDA were determined with and without bilirubin. Bilirubin was labeled with99mTc and its interaction with HSA was also examined. 相似文献