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991.
S. V. Valueva L. N. Borovikova V. V. Koreneva Ya. I. Nazarkina A. I. Kipper V. V. Kopeikin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(7):1170-1173
Nanostructures formed during the reduction of ionic selenium in the selenite-ascorbate redox system in an aqueous solution of bovine serum albumin (BSA) were studied using static and dynamic light scattering and flow birefringence. It was established that this process results in the formation of stable aggregates of selenium nanoparticles that adsorb BSA molecules. It was found that highly-ordered superhigh-molecular-weight spherical nanostructures with high density and unique morphology are formed. Experiments with a cell culture of promyelocytic leukemia HL-60 showed that BSA adsorbed on selenium nanoparticles can inhibit the growth of tumor cells and deactivate free radicals with an efficiency comparable with that of sodium selenite. 相似文献
992.
N. H. Abu-Hamdeh 《Heat and Mass Transfer》2002,38(7-8):687-693
The analytical solutions of equations describing the dynamics of distributed parameter systems are usually complicated in
form and derivations and inconvenient to use for simulation and control system design. The liquid–liquid counter flow heat
exchanger is an example of these disturbed parameter systems. An analytical solution of the dynamics of a symmetrically operated
counter flow heat exchanger in the form of transfer function matrix is investigated in open-loop and close-loop conditions.
The resulting non-linear model was linearized using perturbation approach. A feed-forward path controller to counteract at
any disturbances in the boundary temperature and a non-interactive controller to decouple the outputs were implemented.
Received on 22 February 2001 / Published online: 29 November 2001 相似文献
993.
994.
This work deals with the polymer latexes synthesized using zinc-containing monomers. The effect of the ligand environment of the zinc-containing monomers on the colloidal and rheological properties of the latexes, as well as on mechanical properties of their films is studied. Mixed zinc salts containing the residues of saturated and unsaturated carboxylic acids are shown to be more efficient cross-linking agents than the symmetric salts of this metal. 相似文献
995.
The Laplacian and Dirac operators on critical planar graphs 总被引:6,自引:0,他引:6
R. Kenyon 《Inventiones Mathematicae》2002,150(2):409-439
On a periodic planar graph whose edge weights satisfy a certain simple geometric condition, the discrete Laplacian and Dirac
operators have the property that their determinants and inverses only depend on the local geometry of the graph. We obtain
explicit expressions for the logarithms of the (normalized) determinants, as well as the inverses of these operators. We relate
the logarithm of the determinants to the volume plus mean curvature of an associated hyperbolic ideal polyhedron. In the associated
dimer and spanning tree models, for which the determinants of the Dirac operator and the Laplacian respectively play the role
of the partition function, this allows us to compute the entropy and correlations in terms of the local geometry. In addition,
we define a continuous family of special discrete holomorphic functions which, via convolutions, gives a general process for
constructing discrete holomorphic functions and discrete harmonic functions on critical planar graphs.
Oblatum 6-III-2002 & 12-VI-2002?Published online: 6 August 2002 相似文献
996.
997.
We derive a moderate deviation principle for the lower tail probabilities of the length of a longest increasing subsequence in a random permutation. It refers to the regime between the lower tail large deviation regime and the central limit regime. The present article together with the upper tail moderate deviation principle in Ref. 12 yields a complete picture for the whole moderate deviation regime. Other than in Ref. 12, we can directly apply estimates by Baik, Deift, and Johansson, who obtained a (non-standard) Central Limit Theorem for the same quantity. 相似文献
998.
This paper proposes a model for the parametric representation of linguistic hedges in Zadeh’s fuzzy logic. In this model each linguistic truth-value, which is generated from a primary term of the linguistic truth variable, is identified by a real number r depending on the primary term. It is shown that the model yields a method of efficiently computing linguistic truth expressions accompanied with a rich algebraic structure of the linguistic truth domain, namely De Morgan algebra. Also, a fuzzy logic based on the parametric representation of linguistic truth-values is introduced. 相似文献
999.
Effects of various cardioactive agents and a water extract of the pilose antler of Cervus nippon var. mantchuricus on periodic beating of cultured myocardial cell sheets were examined by using an image analyzing system. Norepinephrine increased the beating rate and the beating amplitude, whereas digoxin and forskolin enlarged only the beating amplitude. Verapamil and propranolol decreased both the beating rate and the beating amplitude. The water extract of the pilose antler showed no remarkable effects in a standard medium (2.1 mM Ca2+). However, it significantly increased the beating amplitude when the beating was suppressed by replacement with a low calcium medium (0.5 mM Ca2+). A similar effect was found for 70% ethanol-soluble and -insoluble fractions of the extract. 相似文献
1000.
P. N. Sapozhnikov 《Journal of Mathematical Sciences》1991,53(6):578-582
An analog of a sufficient statistic is proposed in the finite-dimensional linear space of statistics. It is shown that the unbiased estimator of the linear function of a parameter closest to a given function, expressed in terms of a minimal linearly sufficient statistic, is potentially unbiased and optimal.Translated from Statisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 51–58, 1986. 相似文献