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911.
P. Willsau H. Hübel W. Korten F. Azaiez M. A. Deleplanque R. M. Diamond A. O. Macchiavelli F. S. Stephens H. Kluge F. Hannachi J. C. Bacelar J. A. Becker M. J. Brinkman E. A. Henry A. Kuhnert T. F. Wang J. A. Draper E. Rubel 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(3):351-352
Lifetimes of superdeformed states in194Pb were measured by the Doppler-shift attenuation method. Quadrupole moments around 20 eb, that are constant over the observed frequency range, are derived. The results rule out large centrifugal stretching effects. 相似文献
912.
Dry chitosan is an excellent candidate for facilitated transport membranes that can be utilized in industrial applications, such as fuel cell operations and other purification processes. This article is the first to report temperature effects on transport properties of CO2, H2, and N2 in a gas mixture typical of such applications. At a feed pressure of 1.5 atm, CO2 permeabilities increased (0.381–26.1 barrers) at temperatures of 20–150 °C with decreasing CO2/N2 (19.7–4.55) and CO2/H2 (3.14–1.71) separation factors. The pressure effect on solubilities and permeabilities were fitted to the extended dual mode model and its corresponding mixed gas permeation model. The dual mode and transport parameters, the sorption heats and the activation energies of Henry's and Langmuir's regimes and their pre‐exponential parameters were determined. The Langmuir's capacity constants were utilized to estimate chitosan's glass transition temperature (CO2: 172 °C, N2: 175 °C, and H2: 171 °C). The activation energies of diffusion in the Henry's law and Langmuir regimes were dependent on the collision diameter of the gases. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2620–2631, 2007 相似文献
913.
The elliptic Calogero-Moser Hamiltonian and Lax pair associated with a general simple Lie algebra G are shown to scale to the (affine) Toda Hamiltonian and Lax pair. The limit consists in taking the elliptic modulus τ and the Calogero-Moser couplings m to infinity, while keeping fixed the combination M = m eiδθτ for some exponent δ. Critical scaling limits arise when 1/δ equals the Coxeter number or the dual Coxeter number for the untwisted and twisted Calogero-Moser systems respectively; the limit consists then of the Toda system for the affine Lie algebras G(1) and (G(1))V. The limits of the untwisted or twisted Calogero-Moser system, for δ less than these critical values, but non-zero, consists of the ordinary Toda system, while for δ = 0, it consists of the trigonometric Calogero-Moser systems for the algebras G and GV respectively. 相似文献
914.
915.
The fermion number current is evaluated to leading order in the derivative expansion for chiral fermions in the background of arbitrary Higgs and chiral gauge fields. This current is given by the gauge topological current plus a total divergence term. The total divergence term is absent in Weinberg-Salam theory with one scalar Higgs doublet, even for an arbitrary mass matrix, but appears when several Higgs doublets are present. 相似文献
916.
Eric L. McDowell 《Proceedings of the American Mathematical Society》1998,126(12):3733-3741
The notion of a multi-valued absolute fixed point set (MAFS) will be defined and characterized in the setting of set-valued maps with images containing multiple components.
917.
Thiophenyl glycosides are converted to C-glycosides by reaction with allyl or methallyltri--butylstannane using both “one-electron” and “two-electron” procedures, which give different stereoselectivities in some cases. 相似文献
918.
919.
920.
We have determined the degree of protonation (a) for a weak polybase (poly(2-vinyl-pyridine)) in aqueous solution without added salt by spectrophotometry and conductimetry. For acid solutions of poly(2-vinylpyridine), the use of Kolhrausch's law is adequate; we propose two expressions for the conductance of these solutions (from “ionic association” and “relaxation” models respectively). The values of a, as determined by spectrophotometric and conductimetric measurements, agree well for the highest concentrations and degree of neutralisation (ā). 相似文献