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901.
902.
Veeramani Murugan Ponnusamy Parasuraman Jeyasigamani F. A. Selvin Michael M. Gromiha Kazuhiko Fukui 《Journal of carbohydrate chemistry》2017,36(2-3):111-128
In the present study, the hydroxyl groups at the C4 and C7 positions of sialic acid and C6 position of galactose in Neu5Acα(2–3)Gal (N23G) and the hydroxyl groups at the C8 position of sialic acid and C3 and C4 positions of galactose in Neu5Acα(2–6)Gal (N26G) were substituted with fluorine atoms, respectively. Molecular dynamics simulations of 100 ns duration were carried out to investigate the structural and dynamical behavior of H1 bound with the tri-fluorinated N23G and N26G (FN23G and FN26G). Based on energy analysis, it was concluded that FN26G should be a better binder for hemagglutinin (H1) than FN23G and it might act as an inhibitor for influenza. 相似文献
903.
Kazuhiko Yamaki 《manuscripta mathematica》2013,142(3-4):273-306
In this paper, we formulate the geometric Bogomolov conjecture for abelian varieties, and give some partial answers to it. In fact, we insist in a main theorem that under some degeneracy condition, a closed subvariety of an abelian variety does not have a dense subset of small points if it is a non-special subvariety. The key of the proof is the study of the minimal dimension of the components of a canonical measure on the tropicalization of the closed subvariety. Then we can apply the tropical version of equidistribution theory due to Gubler. This article includes an appendix by Walter Gubler. He shows that the minimal dimension of the components of a canonical measure is equal to the dimension of the abelian part of the subvariety. We can apply this result to make a further contribution to the geometric Bogomolov conjecture. 相似文献
904.
905.
906.
Qun Xu Chun Xu Yanping Wang Wen Zhang Litong Jin Kazuhiko Tanaka Hiroki Haraguchi Akihide Itoh 《Analytical and bioanalytical chemistry》2000,368(8):791-796
An amperometric detector with two working electrodes both modified with polydiphenylamine-dodecyl sulfate (PDPA-DS) was successfully used for the simultaneous determination of electroinactive anions (SO4 2–, Cl–, NO3 –) and cations (Na+, NH4 + and K+) in single-column ion-exclusion cation-exchange chromatography (IEC-CEC). The PDPA-DS chemical modified electrode (CME) was based on the incorporation of dodecyl sulfate (DS) into PDPA by electropolymerization of diphenylamine in the presence of sodium dodecyl sulfate. The electrochemical responses against the anions and cations at the PDPA-DS CME in differential pulse voltammetry were studied. A set of well-defined peaks of electroinactive anions and cations were obtained. The anions and cations were detected conveniently and reproducibly in a linear concentration range 0.01–5.0 mmol/L and their detection limits were in the range 5–9 μmol/L at a signal-to-noise ratio of 3 (S/N = 3). The proposed method was quick, sensitive and simple and was successfully applied to the analysis of lake water samples. The working electrode was stable over one week period of operation with no evidence of chemical and mechanical deterioration. 相似文献
907.
Hiroshi Ishimoto Yuji Zaizen Akihiro Uchiyama Kazuhiko Masuda Yuzo Mano 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(16):2434-2443
We present a shape model of mineral dust particles for use in light-scattering calculations. A spatial Poisson-Voronoi tessellation was applied to simulate the aggregate structure and, therefore, the rough surface of the mineral particles. To develop the shape model, we took into account statistics of shape parameters derived from the cross-sectional areas, maximum dimensions, and perimeters of field-collected dust particles. Light-scattering properties of the modeled Voronoi aggregates were examined by the finite-difference time-domain (FDTD) method. The results of randomly oriented scattering properties agreed with previously reported laboratory measurements of mineral dust particles. 相似文献
908.
Elimination of the arsenic (III) impurity AsF3 from anhydrous hydrogen fluoride has been demonstrated using a bench-scale apparatus (∼500 mL of HF), with a Ag(II) salt AgFAsF6 as a mediator. In this process, AsF3 is oxidized by AgFAsF6 to AsF5. In the next step, AsF5 is eliminated from HF by reaction with NaF. The oxidizer, AgFAsF6, is reduced to AgAsF6 which is regenerated to AgFAsF6 by F2 in HF at room temperature. This method can reduce the arsenic content in HF from a few hundred ppm to the industrially required level (<3 ppm). The results for three other methods (distillation, oxidation by F2 gas, and oxidation by K2NiF6) are reported and compared with the AgFAsF6 method in a preliminary examination (using ∼4 mL of HF). 相似文献
909.
A rhenium complex, [ReBr(CO)3(thf)]2, catalyzes the reaction of a 1,3-dicarbonyl cyclic compound with an acetylene to give a medium-sized cyclic compound in excellent yield. By using isocyanide as an additive, the catalytic activity of the rhenium complex changes dramatically, and the insertion of acetylenes into a carbon-carbon single bond occurs under mild conditions. A plausible mechanism is that the reaction proceeds via the formation of a rhenacyclopentene intermediate, ring opening by a retro-aldol reaction, isomerization, and reductive elimination. 相似文献
910.
The photoluminescence in amorphous semiconductors decays according to the power law t(-delta) at long times. The photoluminescence is controlled by dispersive transport of electrons. The latter is usually characterized by the power alpha of the transient current observed in the time-of-flight experiments. Geminate recombination occurs by radiative tunneling which has a distance dependence. In this paper, we formulate ways to calculate reaction rates and survival probabilities in the case carriers execute dispersive diffusion with long-range reactivity. The method is applied to obtain tunneling recombination rates under dispersive diffusion. The theoretical condition of observing the relation delta=alpha/2+1 is obtained and theoretical recombination rates are compared to the kinetics of observed photoluminescence decay in the whole time range measured. 相似文献