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961.
We consider mixtures of compressible viscous fluids consisting of two miscible species. In contrast to the theory of non-homogeneous
incompressible fluids where one has only one velocity field, here we have two densities and two velocity fields assigned to
each species of the fluid. We obtain global classical solutions for quasi-stationary Stokes-like system with interaction term.
This work was supported by SFB 611. 相似文献
962.
E. J. Wollack D. J. Fixsen R. Henry A. Kogut M. Limon P. Mirel 《International Journal of Infrared and Millimeter Waves》2008,29(1):51-61
We discuss the mechanical, thermal, and electromagnetic properties of a castable microwave absorber consisting of a mixture
of stainless steel powder suspended in a commercially available epoxy. The resulting mixture is well suited for cryogenic
applications. Its coefficient of thermal expansion closely matches most metals to reduce mechanical strain during cool down.
The absorption can be tuned by varying the volume filling fraction of the stainless steel powder in the mixture and exhibits
little change from room temperature to 4 K. We provide simple expressions for the real and imaginary parts of the dielectric
permittivity as a function of frequency and the stainless steel filling fraction. 相似文献
963.
《Analytical letters》2012,45(12):1373-1389
Abstract Four two-component mixtures have been assayed using both Vierordt's and first derivative spectrophotometric methods. Such mixtures are acepifylline and phenobarbitone, phenylbutazone and amidopyrine, procaine and caffeine, and sulphamethoxazole and trimethoprim. These selected applications illustrate the relative ease and simplicity offered by first derivative spectrophotometry for the assay of two component mixtures with spectral interferences from matrix formulations. 相似文献
964.
《Physics and Chemistry of Liquids》2012,50(1):39-45
Abstract Ultrasonic velocities and intermolecular free lengths in binary liquid mixtures of CC4 with toluene, aniline, o-cresol, m-cresol and p-cresol have been calculated theoretically, at different compositions and at temperature 298 K, based on Free Length Theory as revised recently by Kalidoss. It is observed that there is a close agreement of calculated velocities with experimental ones. The shape and thermostatic state picture built up in this formulation could be considered as a good representation of molecular state. 相似文献
965.
《Physics and Chemistry of Liquids》2012,50(2):211-216
Abstract Experimental solubilities are reported for trans-stilbene dissolved in six binary alkane + 1-butanol solvent mixtures at 25°C. The alkane cosoivents studied were hexane, heptane, octane, cyclohexane, methylcyclohexane and 2,2,4-trimethylpentane. Results of these measurements are used to test two mathematical representations based upon the combined Nearly Ideal Binary Solvent (NIBS)/Redlich-Kister and Modified Wilson equations. For the six systems studied, the Combined NIBS/Redlich-Kister equation was found to provide the better mathematical representation of the experimental data, with overall average absolute deviations between measured and calculated values being approximately ±0.6%. Slightly larger deviations were noted in the case of the Modified Wilson equation. 相似文献
966.
《Physics and Chemistry of Liquids》2012,50(1):113-136
Abstract The excess volume VE of the ternary water + diacetone alcohol (or DAA) + 2-propanol and of the three binaries water + DAA, water + 2-propanol and DAA + 2-propanol was evaluated from experimental density data (2772 values) as a function of the pressure P (between 0.1 MPa and 65 MPa), the temperature T (303.15K, 323.15K and 343.15K) and the composition. Various representative models are discussed. It is possible to account for the values of the density with an average absolute deviation of about 0.06% in the experimental P-T domain. 相似文献
967.
《Physics and Chemistry of Liquids》2012,50(2):279-284
Tricritical behaviour in three dimensions is accessible to experiment in, for example, 4He–3He mixtures and some polymeric assemblies. Here, by largely heuristic arguments, which appeal however to some specific model Hamiltonians, we indicate how one can understand the gist of the experimental results near the tricritical point in the systems cited above. We point out that the spin fluctuations at the tricritical point are much weaker than those at the critical point, which leads to the conclusion that the tricritical behaviours can be described well by the mean-field exponents with logarithmic corrections, at d = 3. 相似文献
968.
《Physics and Chemistry of Liquids》2012,50(2):171-182
Measurements of ultrasonic speeds, isentropic compressibilities and viscosities were carried out for six ternary mixtures namely dimethylsulphoxide (1) + 1,2-dichlorobenzene (2) + 1-alkanols (3) at 303.15 K. The 1-alkanols include 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol and 1-octanol. The ultrasonic speeds of these ternary mixtures were also evaluated on the basis of Jacobson's free length theory and Schaaff's collision factor theory. From the viscosity data, deviations in viscosity and interaction parameters for various models were also calculated. An attempt has also been made to explain the nature of intermolecular interactions in the light of deviation in isentropic compressibilities and interaction parameter. 相似文献
969.
The acidity constants of 4-(2-pyridylazo)resorcinol (PAR, Scheme 1) in binary mixtures of methanol-water at 25 °C and an ionic strength of 0.1 M have been determined spectrophotometrically. DATa ANalysis (DATAN) program applied for determination of acidity constants. As percent of methanol increases in solvent mixtures the pKa constants also increased. There is linear relationship between acidity constants and the mole fraction of methanol in the solvent mixtures. Effect of solvent composition on acidity constants and pure spectrum of each component are also discussed. 相似文献
970.
The structural theory of short-term damage is generalized to the case where the undamaged components of a granular composite deform nonlinearly. The basis for this generalization is the stochastic elasticity equations for a granular composite with porous components whose skeletons deform nonlinearly. Microvolumes of the composite components meet the Huber–Mises failure criterion. Damaged microvolume balance equations are derived for the physically nonlinear materials of the components. Together with the equations relating macrostresses and macrostrains of a granular composite with porous nonlinear components, they constitute a closed-form system. The system describes the coupled processes of physically nonlinear deformation and microdamage. Algorithms for calculating the microdamage–macrostrain relationship and plotting deformation diagrams are proposed. Uniaxial tension curves are plotted for the case where microdamages occur in the linearly hardened matrix and do not in the inclusions, which are linearly elastic 相似文献