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31.
The second law of thermodynamics in nonextensive statistical mechanics is discussed in the quantum regime. Making use of the convexity property of the generalized relative entropy associated with the Tsallis entropy indexed by q, Clausius' inequality is shown to hold in the range q in (0, 2]. This restriction on the range of the entropic index, q, is purely quantum mechanical and there exists no upper bound of q for validity of the second law in classical theory. 相似文献
32.
Jackson YA Rajagopal D Bendolph J Guillory M Lakshmikantham MV Yang J Cava MP 《Organic letters》2003,5(11):1883-1885
[reaction: see text] The preparation of 1,3,5,7-tetramethyl-4,8-dihydrobenzo[1,2-c:4,5-c']dithiophene-4,8-dione and its conversion to the corresponding mono- and dithione are described. 相似文献
33.
We present the dispersion relations for quasiparticle excitations about the color-flavor locked ground state of QCD at high baryon density. In the presence of condensates which pair light and strange quarks there need not be an energy gap in the quasiparticle spectrum. This raises the possibility of gapless color superconductivity, with a Meissner effect but no minimum excitation energy. Analysis within a toy model suggests that gapless color superconductivity may occur only as a metastable phase. 相似文献
34.
35.
The IR and Raman spectra are measured and analysed for sodium pyrophosphate decahydrate. The spectra are interpreted on the
basis of P2O
7
4−
ion and water vibrations. The observed results fit with the features predicted for the factor goup model. The appearance
of two sets of frequencies in the stretching and bending regions of water suggests the existence of two kinds of water molecules
in the crystal. This is confirmed by deuterium substitution. 相似文献
36.
Kuldeep Sharma Gopal V. Pawar Sanjeev Giri Sriram Rajagopal Ramesh Mullangi 《Biomedical chromatography : BMC》2012,26(12):1589-1595
A highly sensitive, rapid assay method has been developed and validated for the estimation of bicalutamide in mouse plasma using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the negative‐ion mode. The assay procedure involves extraction of bicalutamide and tolbutamide (internal standard, IS) from mouse plasma with a simple protein precipitation method. Chromatographic separation was achieved using an isocratic mobile phase (0.2% formic acid:acetonitrile, 35:65, v/v) at a flow rate of 0.5 mL/min on an Atlantis dC18 column (maintained at 40 ± 1°C) with a total run time of 3.0 min. The MS/MS ion transitions monitored were m/z 428.9 → 254.7 for bicalutamide and m/z 269.0 → 169.6 for IS. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 1.04 ng/mL and the linearity range extended from 1.04 to 1877 ng/mL. The intra‐ and inter‐day precisions were in the ranges of 0.49–4.68 and 2.62–4.15, respectively. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
37.
38.
Barry Bernstein K. Rajagopal 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2008,59(3):537-553
A thermodynamic framework for hypoelasticity is constructed based on a modified Gibbs Function which depends on the stress
deviator and specific volume. In the hypoelastic equations considered here, the stress deviator is obtained from a rate equation
involving the corotational derivative and coefficients which depend on the invariants of the stress deviator as well as specific
volume. Non-negative entropy production is enforced, leading to a non-dissipative condition in the sense that entropy is produced
only by heat transfer. The resulting conditions lead to relations among the coefficients in the rate equation. These relations
underdetermine the coefficients, so that there is leeway in specifying these coefficients. An example of a set of rate equations
which satisfy the thermodynamics is presented. 相似文献
39.
We discuss the flow of BKZ fluids in an orthogonal rheometer. Some analytical results are proved, and numerical solutions are obtained for the Currie model. These solutions show a boundary layer behavior at high Reynolds numbers and the possibility of discontinuous solutions or nonexistence at high Weissenberg numbers. 相似文献
40.