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941.
942.
943.
It is shown that magnetic drift waves are unstable in the presence of electron temperature anisotropy. Saturation by a quasilinear process which reduces the anisotropy is discussed. 相似文献
944.
945.
K P Shukla 《Pramana》1978,10(1):17-31
A perturbation method in which attractive forces are taken as perturbation of the repulsive (reference) forces is applied
to calculate the thermodynamic properties of (12-6-n) fluids in terms of the properties of hard-sphere fluid. The numerical values of the thermodynamic properties (free energy
per particle, compressibility and excess internal energy) for a range of temperature and density are given for (12-6-8) fluids.
Further, two perturbation schemes are adopted to evaluate the total radial distribution function using the EXP version of
the optimized cluster theory (OCT). The numerical results are reliable as reported at two states (T* = 1·036,ρ* = 0·65 andT* = 0·719ρ* = 0·85) for the (12-6-8) fluid and the Lennard-Jones (12-6) fluid as well. 相似文献
946.
Summary An accurate method has been described for the determination of cysteine, cystine and methionine at the mg level with the use of ammonium hexanitratocerate(IV) as the oxidant. The sample is reacted with an excess of Ce(IV) solution at room temperature (25°) for about 30 min; the unreacted Ce(IV) reagent is then determined by titrating against Fe(II) using ferroin indicator. The precision and accuracy are within ±0.5%.
Zusammenfassung Eine genaue Methode zur Bestimmung von Milligrammengen Cystein, Cystin bzw. Methionin mit Ammoniumhexanitratocerat(IV) als Oxydationsmittel wurde beschrieben. Man läßt die Probe mit überschüssiger Ce(IV)-Lösung bei Zimmertemperatur reagieren und bestimmt nach ungefähr 30 min den Überschuß durch Titration mit Fe(II) gegen Ferroin als Indikator. Die Genauigkeit liegt innerhalb ±0,5%.相似文献
947.
It is shown analytically that the convective saturation of parametric instabilities in an infinite inhomogeneous medium can disappear in the presence of background turbulence. Absolute instability then occurs. 相似文献
948.
A molecular model based on an equation of state for pure argon is applied to various systems involving appreciably nonspherical molecules. Since the pure components are not described adequately, their potential parameters are fitted at each temperature separately to ensure the proper vapor pressures and liquid volumes. Used in this way, the model makes reasonable predictions of the thermodynamic behavior of the binary mixtures considered. Again, the introduction of a binary parameter in the dispersion potential does not lead to any significant overall improvement. 相似文献
949.
The thermal, mechanical and spectral properties of complex formed by picric acid with naphthalene and anthracene respectively have been studied using phase-diagram, linear velocity of solidification, degree of undercooling, fracture value, modulii of elasticity and IR, UV-visible spectral measurements. The phase-diagrams show that the 1:1 molecular complexes which are formed in these systems are stable in the solid state and remain intact in the molten state. The kinetics of solidification in both follows the Hilling and Turnbull equation and the observed kinetic data suggest the Winegard et al, mechanism for the solidification phenomena in the two complexes. The experimental and the theoretically calculated values of heats of fusion were compared. These properties of the pure components and the complexes were studied in the light of molecular interactions which play an important role in deciding the crystal structure of binary organic systems with the formation of congruent melting compounds having structures consisting of infinite stacks of alternate donor and acceptor molecules. 相似文献
950.