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81.
82.
Synthesis of grafting silane on a hydro soluble cellulose ether (HPMC) was described. In alkaline medium, this derivate is under gel form. With a decrease of the pH, a self-hardening occurs due to the silanol condensation. For potential biomedical use, we described the silated-HPMC synthesis, the gel behavior after steam sterilization and the parameters of the silanol condensation i.e. pH, silane percentage and temperature. Minimum kinetic of the condensation was observed for pH between 5.5 and 6.5. So temperature catalyzed the reaction and the self-hardening speed was increased by silane percentage. 相似文献
83.
John E. Gilbert Andrea R. Nahmod 《Transactions of the American Mathematical Society》1999,351(8):3267-3300
The study of bilinear operators associated to a class of non-smooth symbols can be reduced to ther study of certain special bilinear cone operators to which a time frequency analysis using smooth wave-packets is performed. In this paper we prove that when smooth wave-packets are replaced by Walsh wave-packets the corresponding discrete Walsh model for the cone operators is not only -bounded, as Thiele has shown in his thesis for the Walsh model corresponding to the bilinear Hilbert transform, but actually improves regularity as it maps into a Hardy space. The same result is expected to hold for the special bilinear cone operators.
84.
Gilbert Greefrath 《ZDM》1999,31(3):91
Information
Allgemeine Mathematik: Mathematik und Realit?t Darmstadt, 29.9–1.10.1999 相似文献85.
86.
87.
Approximation in the finite element method 总被引:2,自引:0,他引:2
Gilbert Strang 《Numerische Mathematik》1972,19(1):81-98
Summary The rate of convergence of the finite element method depends on the order to which the solutionu can be approximated by the trial space of piecewise polynomials. We attempt to unify the many published estimates, by proving that if the trial space is complete through polynomials of degreek–1, then it contains a functionv
h
such that |u–v
h
|
s
ch
k–s|u|
k
. The derivatives of orders andk are measured either in the maximum norm or in the mean-square norm, and the estimate can be made local: the error in a given element depends on the diameterh
i
of that element. The proof applies to domains in any number of dimensions, and employs a uniformity assumption which avoids degenerate element shapes.This research was supported by the National Science Foundation (GP-13778). 相似文献
88.
89.
G. V. Veriovkin E. N. Gilbert V. A. Mikhailov V. A. Yakhina 《Journal of Radioanalytical and Nuclear Chemistry》1980,59(2):361-365
A neutron activation (NA) method for the determination of 24 microimpurities in germanium has been developed. The method is based on the separation of the matrix and isotopes genetically connected by extraction chromatography. 相似文献
90.
A method of calculating expressions of the type which is simpler than that based on Wick's theorem is proposed. Expressions of the above type are widely used in studying the effects of temperature in electron and neutron diffraction. 相似文献