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991.
Prof. Dr. F. J. Studnička 《Monatshefte für Mathematik》1899,10(1):338-342
Ohne Zusammenfassung 相似文献
992.
Summary The aim of our study was to monitor Cyclosporine A (CA) during a long-term period and to determine whether the whole-blood
levels, estimated by HPLC and radio-immunoassay (RIA), provide a relevant indicator of the toxic effect of CA, of the interference
of endogenous substances with CA and of interactions of erythromycin and ketoconazole with CA metabolims. The ratios of CA
concentrations, estimated by RIA and by HPLC were calculated in order to analyse changes in CA metabolism. A decrease in this
ratio was observed in these patients during periods of erythromycin and ketoconazole therapy deteriorating hepatic function.
We observed unusual higher CA concentrations measured by HPLC compared with RIA in heart transplant patient with marked renal
insiffuciency after one-year follow-up period of treatment of CA. The comparison of CA whole-blood levels estimated using
HPLC and RIA makes it possible to analyse the individual biotransformation of CA to its metabolites, and interference of endogenous
substance in special clinical situations. 相似文献
993.
Hye Seok Park Dong Wan Seo Seung Woo Choi Young Gi Jeong Ju Ho Lee Dong Il Kim Whan‐Gi Kim 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1792-1799
Branched sulfonated poly(ether ketone sulfone)s (Br‐SPEKS) were prepared with bisphenol A, bis(4‐fluorophenyl)sulfone, 3,3′‐disodiumsulfonyl‐4,4′‐difluorobenzophenone, and THPE (1,1,1‐tris‐p‐hydroxyphenylethane), respectively, at 180 °C using potassium carbonate in NMP (N‐methylpyrrolidinone). THPE, as a branching agent, was used with 0.4 mol % of bisphenol A to synthesize branched copolymers. Copolymers containing 10–50 mol % disulfonated units were cast from dimethylsulfoxide solutions to form films. Linear sulfonated poly(ether ketone sulfone)s (SPEKS) were also synthesized without THPE. The films were converted from the salt to acid forms with dilute hydrochloric acid. A series of copolymers were studied by Fourier transform infrared, 1H‐NMR spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of sulfonated polymers with water and methanol. The ion‐exchange capacity (IEC), a measure of proton conductivity, was evaluated. The synthesized Br‐SPEKS and SPEKS membranes exhibit conductivities (25 °C) from 1.04 × 10?3 to 4.32 × 10?3 S/cm, water swell from 20.18 to 62.35%, IEC from 0.24 to 0.83 mequiv/g, and methanol diffusion coefficients from 3.2 × 10?7 to 4.7 × 10?7 cm2/S at 25 °C. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1792–1799, 2008 相似文献
994.
Spectra of unicyclic graphs 总被引:8,自引:0,他引:8
Unicyclic graphs are discussed in the context of graph orderings related to eigenvalues. Several theorems involving lexicographical ordering by spectral moments as well as the ordering by the largest eigenvalue are proved. An appendix contains a table of the 89 unicyclic graphs on eight vertices together with their spectra, spectral moments and characteristic polynomials.Carnegie Research Fellow, University of Stirling, 1985–86. 相似文献
995.
Every LCC loop Q with Inn Q abelian is nilpotent class two. A loop Q of nilpotency class two is LCC ? L(x, y) = L(y, x) for all x, y ∈ Q ? ?/Z(Mlt Q) is abelian ? [x, y, z] = [x,z,y] for all x, y, z ∈ Q ? [x, y, z] = [xy, z][x, z]?1 for all x, y, z ∈ Q. All nilpotent LCC loops of order p2 are described, and some of their multiplication groups are computed. 相似文献
996.
A. Birštunas 《Lithuanian Mathematical Journal》2008,48(2):174-187
We study sequent calculus for multi-modal logic K D45n and its complexity. We introduce a loop-check free sequent calculus. Loop-check is eliminated by using the marked modal operator
□i•, which is used as an alternative to sequents with histories ([8], [3], [5]). All inference rules are invertible or semi-invertible.
To get this, we use or branches beside common and branches. We prove the equivalence between known sequent calculus and our newly introduced efficient sequent calculus.
We concentrate on the complexity analysis of the introduced sequent calculus for multi-modal logic K D45n. We prove that the space complexity of the given calculus is polynomial (O(l
3)). We show the maximum height of the constructed derivation tree that leads to the reduction of the time and space complexity.
We present a decision algorithm for multi-modal logic K D45n and some nontrivial examples to improve the introduced loop-check free sequent calculus. 相似文献
997.
Guey‐Sheng Liou Po‐Han Lin Hung‐Ju Yen Yang‐Yen Yu Wen‐Chang Chen 《Journal of polymer science. Part A, Polymer chemistry》2010,48(6):1433-1440
In this study, a novel synthetic route was developed to prepare polyimide–nanocrystalline–titania hybrid optical films with a relatively high titania content (up to 50 wt %) and thickness (20–30 μm) from soluble polyimides containing hydroxyl groups. Two series of newly soluble polyimides were synthesized from the hydroxy‐substituted diamines with various commercial tetracarboxylic dianhydrides. The hydroxyl groups on the backbone of the polyimides could provide the organic–inorganic bonding and resulted in homogeneous hybrid solutions by controlling the mole ratio of titanium butoxide/hydroxyl group. AFM, SEM, TEM, and XRD results indicated the formation of well‐dispersed nanocrystalline‐titania. The flexible hybrid films could be successfully obtained and revealed relatively good surface planarity, thermal dimensional stability, tunable refractive index, and high optical transparency. A three‐layer antireflection coating based on the hybrid films was prepared and showed a reflectance of less than 0.5% in the visible range indicated its potential optical applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1433–1440, 2010 相似文献
998.
A. Andraši 《The European Physical Journal C - Particles and Fields》2001,18(3):601-612
We test the renormalization of Wilson operators and the Mandelstam–Leibbrandt gauge in the case when the sides of the loop
are parallel to the vectors used in the M–L gauge. Graphs which in the Feynman gauge are free of ultra-violet divergences, in the M–L gauge show
double divergences and single divergences with non-local Si and Ci functions. These non-local functions cancel out when we
add all graphs together and the constraints of gauge invariance are satisfied. In Appendix C we briefly discuss the problems
of the M–L gauge for loops containing spacelike lines.
Received: 31 May 2000 / Published online: 23 January 2001 相似文献
999.
1000.