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71.
72.
Gyrgy Kalaus Lajos Szab Jnos les Csaba Szntay Imre Juhsz Istvn Greiner Jnos Brlik Mria Kajtr‐Peredy 《Journal of heterocyclic chemistry》2000,37(2):245-251
The individual epimerization steps of vincadifformine ( 1 ), deethylvincadifformine isomers ( 2,3 ), their synthetic intermediates ( 4–13 ) as well as that of simpler compounds with D‐secoaspidospermane skeleton ( 15–17 ) were studied a ) in protic medium (boiling deuteroacetic acidic) and b ) under reductive (with sodium borodeuteride in boiling acetic acid, or with sodium borohydride in boiling deuteroacetic acid) conditions. 相似文献
73.
Stiedl Bernadett Kovcs-Kiss Dorottya Ludnyi Krisztina Bdis Attila Klebovich Imre Antal Istvn 《Chromatographia》2010,71(1):109-113
Tolperisone HCl is a central muscle relaxant, which was incorporated in a matrix system formulated with poly(ethylene oxide)–PEO, in order to achieve adequate gastric residence time. This tablet presents considerable analytical difficulties in the quantitative determination of the drug, because the PEO matrix causes significant increase of viscosity in the samples. Our purpose was to develop a reproducible sample preparation method, which is adapted from parameters of the in vitro dissolution test and validate an LC-UV analytical method, which allows good recovery of the drug (99.97%). The developed analytical method was suitable for quantitative analysis of tolperisone HCl in matrix tablets. 相似文献
74.
s , the surface diffusion coefficient, Ds
′, and the surface reaction rate coefficient, βs
′, of Cu on alumina are determined in the temperature range 1048–1198 K. Measuring simultaneously the time dependence of the
effective thickness, Heff(t), the lateral shift of the boundary, y(t) of beaded films (BF) and using vapour pressure data we concluded that the process
is controlled by surface reaction at the perimeters of beads. Supposing Arrhenius-type temperature dependence for Ds
′, βs
′ and λs the activation energies and preexponential factors have been calculated.
Received: 2 October 1996/Accepted: 27 November 1996 相似文献
75.
Zoltán Imre Szabó 《Annals of Global Analysis and Geometry》2008,34(4):381-386
This article negatively answers the long standing problem concerning the existence of non-Berwald Landsberg metrics. 相似文献
76.
77.
Imre Bucsi Szabolcs Cserényi Károly Felf?ldi Mihály Bartók 《Reaction Kinetics and Catalysis Letters》2006,87(2):281-289
Summary We synthesized C9-O-silyl ethers of cinchonidine and dihydrocinchonidine (1-8), seven of which have not been known before. The structures of the compounds were verified by ESI-ion-trap MS and 1H-NMR. Fragmentation of silyl ethers containing Si-phenyl bonds was studied for the first time. The compounds obtained will
be utilized as chiral catalysts of certain asymmetric syntheses.</o:p> 相似文献
78.
Attila R.Imre 《高分子科学》2003,(2):241-249
In this paper we would like to give a brief review about the extensibility of the liquid-liquid locus into the negativepressure region. Negative pressure states are hardly explored; most researchers believe that the pressure scale ends at p = 0.We would like to show that this is not true, the p = 0 point is not a special point for liquids, it can be "easily" crossed. We aregoing to give a few example, where the extension of liquid-liquid locus for polymer blends and solutions below p = 0 givesus some interesting results, like the merging of UCST and LCST branches in weakly interacting polymer solutions or thereason why most UCST blends exhibit pressure induced immiscibility. Also, we will see what happens with the immiscibilityisland of aqueous polymer solutions when -- reaching the critical molar mass -- it "disappears". 相似文献
79.
80.
We consider Nash equilibria in 2‐player random games and analyze a simple Las Vegas algorithm for finding an equilibrium. The algorithm is combinatorial and always finds a Nash equilibrium; on m × n payoff matrices, it runs in time O(m2nloglog n + n2mloglog m) with high probability. Our result follows from showing that a 2‐player random game has a Nash equilibrium with supports of size two with high probability, at least 1 − O(1/log n). Our main tool is a polytope formulation of equilibria. © 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2007 相似文献