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921.
A. L. Chistov 《Journal of Mathematical Sciences》2005,126(2):1117-1127
Consider a projective algebraic variety V, which is the set of all common zeros of homogeneous polynomials of degrees less than d in n + 1 variables over a field of characteristic zero. We suggest an algorithm that decides whether two (or more) given points of V belong to the same irreducible component of V. We also show how to construct, for each s < n, an (s + 1)-dimensional plane in the projective space such that the intersection of every irreducible component of dimension n — s of V with the constructed plane is transversal and is an irreducible curve. These algorithms are deterministic and polynomial in dn and the input size. Bibliography: 9 titles.Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 292, 2002, pp. 130–152.This revised version was published online in April 2005 with a corrected cover date and article title. 相似文献
922.
Metal ion uptake properties of polystyrene-supported chelating polymer resins functionalized with (i) glycine, (ii) hydroxy
benzoic acid, (iii) Schiff base and (iv) diethanol amine have been investigated. The effects of pH, time and initial concentration
on the uptake of metal ions have been studied. The uptake of metal ion depends on pH. The resins are more selective at pH
10 for Pb(II) and Hg(II), whereas at pH 6 they are found to be Cd(II) and Cr(VI) selective. Metal ion uptake properties of
resins follow Freundlich’s equation. The resins are recyclable and are therefore employed for the removal of heavy metal pollutants
from industrial waste water. 相似文献
923.
924.
925.
Valiuliene G. Zeliene A. Jasulaitiene V. Mozginskiene I. 《Russian Journal of Applied Chemistry》2003,76(1):71-75
X-ray photoelectrom spectroscopy was used to study the composition of the initial and electrochemically reduced cobalt coating formed by the adsorption procedure involving treatment of a carbon glass electrode in a solution of Co(II) ammine complexes, hydrolytic washing in water, and conversion to sulfide in Na2S solution. 相似文献
926.
927.
It is usually assumed, in classical statistical mechanics, that the temperature should coincide, apart from a suitable constant factor, with the mean kinetic energy of the particles. We show that this is not the case for Fermi–Pasta–Ulam systems, in conditions in which energy equipartition between the modes is not attained. We find that the temperature should be rather identified with the mean value of the energy of the low frequency modes. 相似文献
928.
We propose an integrable deformation of the known model of two interacting tops on the algebra so(p,q). We consider particular cases including the generalized Lagrange and Kovalevskaya tops. We construct the Lax matrices and the corresponding classical R-matrices. 相似文献
929.