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71.
M. Elena Mart��n M. Luz S��nchez Jos�� C. Corchado Aurora Mu?oz-Losa Ignacio Fdez. Galv��n Francisco J. Olivares del Valle Manuel A. Aguilar 《Theoretical chemistry accounts》2011,128(4-6):783-793
The possible influence of the solvent Stark effect (SSE) on the solvatochromic shift in electron transitions has been analyzed by using the ASEP/MD (averaged solvent electrostatic potential from molecular dynamics) method. With this purpose, four molecules, two polar (acrolein and formaldehyde) and two non-polar (p-difluorobenzene and trans-difluoroethene) have been studied in solvents of diverse polarity. Independently of the nature of the system we found that the contribution of SSE on the average value of the solvent shift or on the multipole moment values is negligible. In the case of centro-symmetric molecules, our results permit to discard the SSE as cause of the solvent shift found, which must be assigned to the electrostatic interaction of the solute quadrupole and higher multipoles with the solvent. As the SSE values provide also a measure of the errors introduced by the mean field approximation (MFA), these results indicate that MFA permits a very accurate determination of the solvent shift at the same time that it reduces drastically the computational cost. Finally, a new procedure suited to the ASEP/MD method has been presented that permits to estimate the inhomogeneous broadening of spectral bands, complementing the information provided by mean field theories. This procedure does not need additional quantum calculations and its computational cost is minimal. 相似文献
72.
Pál Perjési Gábor Maász Renáta Reisch András Benk? 《Monatshefte für Chemie / Chemical Monthly》2012,5(3):1107-1114
Abstract
The non-enzyme-catalyzed reaction of reduced glutathione (GSH) with two tumor cell cytotoxic cyclic chalcone analogues was investigated by reversed-phase high-performance liquid chromatography (RP-HPLC). HPLC analysis of the reaction mixtures indicated the formation of two diastereomeric chalcone–GSH adducts in each case, whose structural assignments were supported by MALDI-TOF-MS and HPLC–MS with electrospray ionization (ESI) measurements. Such reactivity accounts for the previously observed effect of the two cyclic chalcone analogues on the in vivo cellular thiol level of Jurkat T cells. 相似文献73.
Á Császár 《Acta Mathematica Hungarica》2002,95(1-2):83-99
We study properties of the operation
, defined for structures corresponding to different subcategories of MER, as merotopies, filter merotopies, contiguities,
-contiguities and closures. In particular, we examine commutativity of
and the operation according to which a structure induces a structure of another type (as e.g.\ a merotopy induces a closure) and the inverse operations of the former. 相似文献
74.
A new trust-region and affine scaling algorithm for linearly constrained optimization is presented in this paper. Under no
nondegenerate assumption, we prove that any limit point of the sequence generated by the new algorithm satisfies the first
order necessary condition and there exists at least one limit point of the sequence which satisfies the second order necessary
condition. Some preliminary numerical experiments are reported.
The work was done while visiting Institute of Applied Mathematics, AMSS, CAS. 相似文献
75.
Tishchenko G Dybal J Mészárosová K Sedláková Z Bleha M 《Journal of chromatography. A》2002,954(1-2):115-126
Ni2+ complexes of the chelating nonporous and porous bead sorbents based on methacrylic esters crosslinked with ethylene dimethacrylate were used in isolation of the horseradish peroxidase-specific immunoglobulin IgG1 from the crude mouse ascitic fluid by immobilized metal ion affinity chromatography (IMAC). Iminodiacetic and aspartic acids were attached to porous poly(glycidyl methacrylate) beads differing in size, morphology and chemical composition. Ethylenediaminetriacetic acid and quinolin-8-ol chelating groups were attached mainly to the surface hydroxyl groups in nonporous poly(diethylene glycol methacrylate) beads through spacers. The latter sorbents exhibited better kinetic characteristics than the former but a very low IgG1 sorption capacity. In a single-step IMAC procedure, the best efficiency in the specific IgG1 purification was obtained with porous sorbents (recovery 92%, purity 73%). Differences in IMAC separations are discussed from the point of view of morphology of polymer beads as well as of the type and concentration of chelating ligands. 相似文献
76.
Widmann E Eades J Ishikawa T Sakaguchi J Tasaki T Yamaguchi H Hayano RS Hori M Torii HA Juhász B Horváth D Yamazaki T 《Physical review letters》2002,89(24):243402
Using a newly developed laser-microwave-laser resonance method, we observed a pair of microwave transitions between hyperfine levels of the (n,L)=(37,35) state of antiprotonic helium. This experiment confirms the quadruplet hyperfine structure arising from the interaction of the antiproton orbital angular momentum, the electron spin and the antiproton spin as predicted by Bakalov and Korobov. The measured frequencies of nu(+)(HF)=12.895 96+/-0.000 34 GHz and nu(-)(HF)=12.924 67+/-0.000 29 GHz agree with recent theoretical calculations on a level of 6x10(-5). 相似文献
77.
Hori M Eades J Hayano RS Ishikawa T Sakaguchi J Tasaki T Widmann E Yamaguchi H Torii HA Juhász B Horváth D Yamazaki T 《Physical review letters》2002,89(9):093401
Initial distributions of metastable antiprotonic (4)He and (3)He atoms over principal (n) and angular momentum (l) quantum numbers have been deduced using laser spectroscopy experiments. The regions n = 37-40 and n = 35-38 in the two atoms account for almost all of the observed fractions [(3.0 +/- 0.1)% and (2.4 +/- 0.1)%] of antiprotons captured into metastable states. 相似文献
78.
P. Révész 《Stochastic Processes and their Applications》1983,15(2):169-179
Let U1, U2,… be a sequence of independent, uniform (0, 1) r.v.'s and let R1, R2,… be the lengths of increasing runs of {Ui}, i.e., X1=R1=inf{i:Ui+1<Ui},…, Xn=R1+R2+?+Rn=inf{i:i>Xn?1,Ui+1<Ui}. The first theorem states that the sequence can be approximated by a Wiener process in strong sense.Let τ(n) be the largest integer for which R1+R2+?+Rτ(n)?n, and . Here Mn is the length of the longest increasing block. A strong theorem is given to characterize the limit behaviour of Mn.The limit distribution of the lengths of increasing runs is our third problem. 相似文献
79.
80.