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1.
Karol Jankowski Danuta Rutkowska Andrzej Rutkowski 《Theoretical chemistry accounts》1978,48(2):119-125
It is shown that the Galerkin-Petrov method if applied in a controlled way yields reliable results for excited states of the
same symmetry classifications as the ground state. Computations are performed for the 21
S and 31
S states of He. The problem of optimizing nonlinear parameters of the basis functions by means of the GP method is discussed.
A special optimization scheme is suggested and numerically illustrated for someS states of He. 相似文献
2.
Abstract— L5178Y-R (LY-R) and L5178Y-S (LY-S) cells differ in sensitivity to UVC radiation (D0 : 2.8 and 9.0 J/m2 respectively, for cells exposed in Fischer's medium). We used these cells and a DNA unwinding technique in conjunction with 1-β-D-arabinosyl cytosine to determine DNA strand breaks accumulating as a result of enzymatic incision during DNA repair. Following UVC exposure DNA strand break accumulation was observed in LY-S cells but not in LY-R cells. The repair defect in LY-R cells is accompanied by a delayed recovery of [3 H]thymidine incorporation. 相似文献
3.
Danuta Fr°Ckowiak Danuta Bauman Izabela Betkowska 《Photochemistry and photobiology》1981,33(5):779-781
Abstract— An electric field enhances the yield of fluorescence of chlorophyll in a liquid crystal solvent. The presented data suggest that the electric field effect is caused by the decrease in the efficiency of fluorescence quenching by ions. Quenching of each polarized component of fluorescence of chlorophyll molecules oriented by the liquid crystal matrix is different. The relative increase in fluorescence yield due to the applied electric field is stronger for a fluorescence component polarized parallel to the direction of liquid crystal orientation than for the perpendicular component. 相似文献
4.
The analysis of microbial communities is of increasing importance in life sciences and bioengineering. Traditional techniques of investigations like culture or cloning methods suffer from many disadvantages. They are unable to give a complete qualitative and quantitative view of the total amount of microorganisms themselves, their interactions among each other and with their environment. Obviously, the determination of static or dynamic balances among microorganisms is of fast growing interest. The generation of species specific and fluorescently labeled 16S ribosomal DNA (rDNA) fragments by the terminal restriction fragment length polymorphism (T-RFLP) technique is a suitable tool to overcome the problems other methods have. For the separation of these fragments polyacrylamide gel sequencers are preferred as compared to capillary sequencers using linear polymers until now because of their higher electrophoretic resolution and therefore sizing accuracy. But modern capillary sequencers, especially multicapillary sequencers, offer an advanced grade of automation and an increased throughput necessary for the investigation of complex communities in long-time studies. Therefore, we adapted a T-RFLP technique to an automated high-throughput multicapillary electrophoresis device (ABI 3100 Genetic Analysis) with regard to a precise qualitative and quantitative characterization of microbial communities. 相似文献
5.
The electrode kinetic parameters of the In(III)/In(I) couple in acidic 4M bromide solution have been determined by means of the rotating disc electrode technique.
Die elektrochemisch-kinetischen Parameter des In(III)/In(I)-Redoxsystems in Bromidlösung (Kurze Mitteilung)
Zusammenfassung Die elektrochemisch-kinetischen Parameter am In(III)/In(I)-Redoxsystem wurden in saurer 4-M-Bromidlösung mittels der rotierenden Scheibenelektrode bestimmt.相似文献
6.
Danuta Czakis-Sulikowska Anna Malinowska 《Journal of Thermal Analysis and Calorimetry》1998,51(2):575-584
New complexes of lead(II) with 2,4′-bipyridyl (L), with the general formulae PbL2X2 (where X ?1=Cl, Br, I, NCS) and PbL3X2 (where (X]?1=NO3, ClO4), have been prepared. Analysis of the IR spectra indicates that the 2,4′-bipyridyl is bonded to the Pb(II) ion through the least hindering N(4′). The thermal decompositions of the complexes were studied under non-isothermal conditions in air. The intermediates of decomposition at different temperatures were characterized by thermal analysis (TG and DTG), chemical analysis and X-ray diffraction. Upon heating, the complexes undergo full or partial deamination. The complexes PbL2Cl2 and PbL2Br2 decompose to volatile lead(II) halide. PbO is the final product of decomposition for the other complexes. 相似文献
7.
Ewa Katzenellenbogen Nina A. Kocharova Georgy V. Zatonsky Maria Bogulska Danuta Witkowska Aleksander S. Shashkov 《Journal of carbohydrate chemistry》2013,32(5):545-558
ABSTRACT Lipopolysaccharide (LPS) of Hafnia alvei 23 has an acid-labile O-specific polysaccharide (OPS) with a pentasaccharide-phosphate repeating unit containing D-Glc1P, D-GlcNAc, L-Fuc, 6-deoxy-D-talose (D-6dTal), 4-acetamido-4,6-dideoxy-D-glucose (D-Qui4NAc), and an O-acetyl group. A partially degraded OPS was obtained by hydrolysis of LPS with 0.25 M sodium acetate in aqueous 0.5% acetic acid. Fractionation of LPS on Sephadex G-200 in DOC buffer allowed isolation of long-chain LPS species which, together with OPS, were studied by methylation analysis, chemical degradations (O-deacetylation, dephosphorylation with 48% hydrofluoric acid, Smith degradation), and 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, and H-detected 1H,13C heteronuclear single-quantum coherence (HSQC) experiments. The following structure of the repeating unit of OPS was established: 相似文献
8.
Danuta Piskorska Janusz Sokolowski Marlin Friesen Gérard Descotes 《Journal of carbohydrate chemistry》2013,32(8):1015-1025
AbstractThe synthesis and structure of N-D-pentopyranosylamines derived from the amines tiyptamine tyramine and the pentoses D-xylose, D-arabinose and D-lyxose are presented. NMR spectroscopy and mass spectrometry were used to verify the proposed α,β-D-pentopyranosylamine structures. 相似文献
9.
10.
Langmuir films of binary mixtures of the following liquid crystal materials: 4-octyl-4′-cyanobiphenyl (8CB) or 4-pentyl-4″-cyano-p-terphenyl (5CT) with 4-(trans-4'-octylcyclohexyl)isothiocyanatobenzene (8CHBT), trans-4-octyl(4′-cyanophenyl)cyclohexane (8PCH) or 4-octyl4′-isothiocyanatobiphenyl (8BT) were investigated. Surface pressure-mean molecular area isotherms were recorded at various mixture compositions. It was found that only liquid crystal materials for which the molecules have a terminal -CN group are able to form a stable monolayer at the air-water interface. Moreover, information about the miscibility or the phase separation of the two components in the mixures was obtained by using the excess area criterion and surface phase rules. 相似文献