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1.
A new preconditioned conjugate gradient (PCG)-based domain decomposition method is given for the solution of linear equations
arising in the finite element method applied to the elliptic Neumann problem. The novelty of the proposed method is in the
recommended preconditioner which is constructed by using cyclic matrix. The resulting preconditioned algorithms are well suited
to parallel computation. 相似文献
2.
T. Szitó J. G. Kiss GY. I. Garab L. A. Mustárdy Á. Faludi-Dániel 《Photochemistry and photobiology》1984,40(1):113-117
Abstract Orientation pattern of the Qy absorption and emission dipoles of chlorophyll a were studied in wild type Scenedesmus obliquus and in mutants deficient in chlorophyll b and carotenoids. Fluorescence polarization ratio at –140°C and linear dichroism at 25°C were measured in whole cells and thylakoids aligned in polyacrylamide gel. Unlike normal thylakoids, mutants displayed fluorescence polarization ratios significantly lower than 1.0 and showed a negative LD signal around 672 nm, indicating the tendency of the Qy dipoles to tilt out from the membrane plane. Such an orientation pattern can also be artificially induced by treating normal thylakoids with linolenic acid. 相似文献
3.
Guralchuk GY Sorokin AV Katrunov IK Yefimova SL Lebedenko AN Malyukin YV Yarmoluk SM 《Journal of fluorescence》2007,17(4):370-376
Optical spectroscopy experiments were used to study the features of cyanine dye 3,3′-dimethyl-9-(2-thienyl)-thiacarbocyanine
iodide (L-21) aggregation in binary solutions DMF:Tris–HCl buffer (pH = 8) containing nucleic acids (DNA or RNA). The appearance
of absorption and luminescence bands associated with J-aggregates and dimers that are formed within the minor groove of DNA
has been observed. The model of L-21 J-aggregate structure is proposed. It has been found that dimers are the building blocks
of L-21 J-aggregates. Disorientation in dimers caused by the minor groove curvature is reason of observation of Davydov splitting
in absorption spectrum of L-21 J-aggregates. In the solution containing DNA the absorption and luminescence bands of L-21
J-aggregates exhibit the specific properties that allows the dye L-21 to be used as a fluorescent probe for DNA detection. 相似文献
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6.
Lebedenko AN Guralchuk GY Sorokin AV Yefimova SL Malyukin YV 《The journal of physical chemistry. B》2006,110(36):17772-17775
Using fluorescent microscopy and microspectroscopy, optical properties and morphology transformations in individual pseudoisocyanine (PIC) J-aggregates in aqueous electrolyte solutions have been explored. A stringlike structure of J-aggregates with a string diameter much less than 1 microm has been observed. Photodestruction of the strings under short-wavelength excitation has been revealed. Rodlike PIC crystallites, about 1 microm in diameter, have been observed with time. The fluorescence spectrum of rodlike crystallites has been found to differ from that of stringlike J-aggregate and from PIC crystal powder spectra. The crystallites are very stable, and their photodestruction has not been observed under any excitation conditions. It has been found that rodlike crystallites in contrast to stringlike J-aggregates possess optical waveguide properties. The luminescence of crystallites can be observed only at the excitation spot and at butt ends located up to hundreds of micrometers from the excitation spot. 相似文献
7.
GY A'kos 《Optics & Laser Technology》1990,22(6):414-418
A two-dimensional diameter control apparatus has been devised and constructed on the laser scanning principle, which uses a reference grating to determine the outer diameter of an object as well as the position of the scanning beam. 相似文献
8.
A. S. Lebed S. L. Yefimova G. Ya. Guralchuk A. V. Sorokin I. A. Borovoy Yu. V. Malyukin 《Journal of Applied Spectroscopy》2010,77(2):183-188
The interaction of a series of cationic dialkyloxacarbocyanine perchlorate (DiOC
n
) dyes of different degrees of hydrophobicity with micelles of an anionic surfactant, sodium dodecylsulfate (SDS), has been
studied spectrophotometrically in aqueous solutions. The Benesi–Hildebrand equation was used to calculate binding constants
(K
b
) of the dyes to surfactant micelles, the fraction of dye bound to the micelles (f
mic
), and the standard free-energy change (ΔG
0) for the transfer of dye from the aqueous to micellar phase. It has been shown that the interaction of oppositely charged
dye molecules and surfactant micelles is controlled by both electrostatic and hydrophobic interactions. A small increase in
dye hydrophobicity due to lengthening of the hydrocarbon radical has been shown to cause an abrupt nonlinear increase of the
fmic value. This points to a key role of hydrophobic interactions in the binding of dye molecules with the micelles. 相似文献
9.
The thermal degradation of PVC powders and the inhibition of this process by cadmium laurate was investigated by the measurement of discoloration, diffuse reflectance spectra, and the quantity of hydrochloric acid formed. Kinetic analysis of the data obtained by us previously showed that both the data of color measurements and those of diffuse reflectance spectra may be used conveniently for the calculation of the number of double bonds formed during the degradation. 相似文献
10.
Z. Aigner GY. Dombi M. Kata 《Journal of inclusion phenomena and macrocyclic chemistry》1996,25(1-3):145-148
Levonorgestrel dissolves only slightly in water. Attempts were made to increase the solubility properties of this drug by complexing with cyclodextrins. The products were investigated with a dissolution tester and a Sartorius resorption model. X-ray and NMR spectra of the inclusion complexes were analysed. 相似文献