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1.
The energies of negative-parity levels based on two-particle states exhibit a nonlinear behavior at low spins versus the core-rotation energy because the alignment process has not yet been completed for them. This behavior of negative-parity levels in the low-spin region is satisfactorily described upon the inclusion of octupole-octupole interactions. This is demonstrated within the rotational model involving the Coriolis mixing of states for the even-even isotopes 162–168Hf. 相似文献
2.
AbbasA. Zaman 《Particle & Particle Systems Characterization》2003,20(5):342-350
Effects of a low molecular weight physically adsorbed polyethylene oxide (PEO) and the range of the electrostatic repulsion on the rheological behavior of silica dispersions (as a model system) has been investigated. Particular attention is given to the evolution of the rheological behavior with increasing the polymer concentration in the system and also effectiveness of the polymer as a dispersant under extreme conditions (high ionic strength). Results indicate that at small separation distances and low polymer coverage, the polymer chains are long enough to adsorb on the surface of two particles simultaneously causing bridging flocculation in the system and hence increasing the viscosity and linear viscoelastic functions of the dispersion. A significant increase was observed in the viscosity of the dispersion at salt concentrations high enough to eliminate electrostatics between the particles. Under these conditions,the viscosity of the system increased significantly when PEO was added to the dispersion showing that at high electrolyte concentrations, a neutral polymer such as PEO is not able to stabilize the system. 相似文献
3.
The possible types of ordering diagrams of ternary substutional alloys with an fcc lattice are analyzed, taking account of interactions in two coordination spheres.Ural Polytechnic Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 38–41, December, 1992. 相似文献
4.
V. P. Maiboroda I. E. Troyanovskii I. I. Safarov M. G. Vazagashvili I. V. Katalymova 《Journal of Mathematical Sciences》1992,60(2):1379-1382
This article examines the propagation of viscoelastic (elastic) waves in a medium consisting of two layers of finite thickness. It is found that there is a mechanical effect manifest in the monotonic dependence of the damping factor on the parameters of the system. These dependences have distinct maxima and minima, thus making it possible to optimize the damping properties of systems by varying their geometric parameters.Translated from Dinamicheskie, Sistemy, No. 4, pp. 57–62, 1985. 相似文献
5.
P. Hayumbu M. B. Zaman S. S. Munsanje 《Journal of Radioanalytical and Nuclear Chemistry》1995,201(4):333-346
226Ra and232Th specific activities in coal from Maamba Collieries in Zambia have been measured at 46±8 and 56±9 Bq kg–1, respectively. These values are nearly two and a half times larger than the world average for coal and are close to those for lignite or brown coal. Determination of specific activities in coal waste at Maamba and coal ash at the fertilizer factory in Kafue showed enhancement factors of 2.6 and 2.0, respectively. These values are well within the world range of enhancement factors in coal ash. 相似文献
6.
S. A. Vasil'eva Yu. A. Kashina M. V. Kulikova M. N. Zemtsova M. G. Safarov 《Chemistry of Heterocyclic Compounds》1992,28(8):868-871
The reaction of 4-methyl-3,4-epoxytetrahydropyran with potassium thiocyanate occurs with expansion of the oxirane ring and leads to 6-methyl-8-amino-3,7-dioxa-9-thiabicyclo[4,3,0]nonane, the formation of which has been proven by the fact that products of its acylation by acid chlorides of 2-R-cinchonic acids are obtained, and also by the formation of Mannich bases when it is treated with formaldehyde and secondary amines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1039–1042, August, 1992. 相似文献
7.
M. M. R. Talukder M. M. Zaman Y. Hayashi J. C. Wu T. Kawanishi 《Applied biochemistry and biotechnology》2007,141(1):77-83
The thermostability of Cromobacterium viscosum lip ase (EC 3.1.1.3) entrapped in AOT (sodium bis-[2-ethylhexyl] sulfosuccinate) reverse micelles was in creased by the addition
of short-chain polyethylene glycol (PEG 400). Two different approaches were considered: (1) the determination of half-life
time and (2) the mechanistic analysis of deactivation kinetics. The half-life of lipase entrapped in AOT/isooctane reverse
micelles with PEG 400 at 60°C was 28h, ninefold higher than that in reverse micelles without PEG 400. The lip ase entrapped
in both reverse micellar systems followed a series-type deactivation mechanism involving two first-order steps. The deactivation
constant for the first step at 60°C in PEG containing reverse micelles was 0.055 h11, 11-fold lower than that in reverse micelles without PEG, whereas it remained almost constant for the second step. The inactivation
energy of the lip ase entrapped in reverse micelles with and without PEG 400 was 88.12 and 21.97 kJ/mol, respectively. 相似文献
8.
J. Kvasil I. N. Mikhailov R. Ch. Safarov B. Choriev 《Czechoslovak Journal of Physics》1978,28(8):843-856
Some generalizations of the model for odd nuclei suggested by Kerman are considered. The effects of phonon admixtures on matrix elements of Coriolis interaction are studied. Several schemes are considered for studying the role of non-adiabatic effects in the even-even core.One of the authors B. Ch. thanks L. A.Malov and V. O.Nesterenko for many discussions of some questions connected with the determination of the phonon-quasiparticle admixtures. 相似文献
9.
The decoloration yield of oxazine 720 in ethanolic solution was studied as a function of dose rate and concentration of the dye. Linear response for G values to a dose of 1.68 KGy was observed for various dye concentrations. The effect of various organic substances in the radiolysis of the dye was studied and the results were interpreted in terms of scavenging reactions. 相似文献
10.
The flow behavior of bidisperse aqueous silica suspensions has been studied at different electrolyte concentrations as a function of shear rate, total volume fraction of the particles, and volume ratio of small to large particles. It is shown that the range of the electrostatic repulsion plays an important role in determining the viscosity of the suspension. Binary mixtures of particles of longer range repulsive forces showed higher viscosities than the suspensions of shorter range electrostatic interactions. Bimodal suspensions of long-range interactions showed non-Newtonian behavior over wider ranges of shear due to the deformation of the ionic cloud around the particles, which is larger in these systems. The viscosity of bimodal suspensions used in this study was scaled with respect to the viscosity of the related monosized systems and the viscosity of one bimodal suspension at a fixed total volume fraction of the particles, employing our earlier scaling method. The model normalizes the effect of colloidal forces by introducing a scaling factor that collapses the data into a single curve for bimodal suspensions of a particular size ratio, and it is shown that the model is valid for systems with both short-range and long-range repulsive forces. Copyright 1999 Academic Press. 相似文献