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61.
62.
The system to be considered in this paper is
63.
N,N‐Di(arenesulfonyl)‐N′,N′‐dimethyl‐hydrazines, readily prepared from arenesulfonyl chlorides and N,N‐dimethylhydrazine, were heated at 120°C in chlorobenzene to give S‐aryl arenethiosulfonates, ArSSO2Ar, in good yields. 相似文献
64.
An axial non-mechanical scan in the laser Doppler velocimeter (LDV) using a single diffraction grating is demonstrated. The measurement position in this LDV is axially scanned using a wavelength change and a dispersion function of the grating. The experimental result using a sensor probe setup indicates that a scanning function is successfully obtained with a simpler arrangement than that of the LDV previously reported, and the ratio of the scanning range to the working distance can be enhanced by virtue of using larger angular dispersion. 相似文献
65.
Seiichiro Onari Tetsuya Hata Yukio Tanaka Jun-ichiro Inoue 《Journal of Physics and Chemistry of Solids》2008,69(12):3307-3309
In order to clarify the tunneling spectroscopy in high-Tc cuprates, we study electronic state of the surface in the strongly correlated electron systems. First, we obtain Green's function of strongly correlated normal bulk system using the fluctuation exchange (FLEX) approximation. Next, we insert infinite potential into the bulk system and obtain Green's function of surface. We find that the density of states (DOS) in strongly correlated bulk systems are different from that on the surface, and the difference decreases as the magnitude of Coulomb interaction (U) increases. 相似文献
66.
2-Nonen-7-ynedioic or 2-decen-8-ynedioic acid derivatives were treated with an iron reagent generated from FeCl2 and t-BuMgCl in a ratio of 1:4 to give cyclized products after hydrolysis, deuteriolysis, or the addition of carbonyl compounds. Upon reaction with the same iron reagent, 2,7-nonadienedioates afforded bicyclic ketoesters (and their enol forms) after the addition of s-BuOH or carbonyl compounds. 相似文献
67.
Okada S Arayama K Murayama R Ishizuka T Hara K Hirone N Hata T Urabe H 《Angewandte Chemie (International ed. in English)》2008,47(36):6860-6864
68.
The optical resolution of 2-amino-1-phenylethanol (2-APE) by the solvent switch method was investigated using dehydroabietic acid (DAA), a natural chiral acid obtained as one of the main components of disproportionated rosin. The solvent dependency of optical rotation measurements of 2-APE, DAA and the diastereomeric salts suggested solvent control of optical resolution. Both (R)- and (S)-2-APE were resolved, as the first success for aminoalcohols, only by changing the resolving solvents: (S)-2-APE was obtained in high optical purity by a single crystallization operation with polar solvents (epsilon > 50), whereas the efficiency was lower for (R)-2-APE using less polar solvents (20 < epsilon < 40). The results were compared and discussed with reference to the crystal structures of the diastereomeric salts. 相似文献
69.
Yuko Hata Toyoko Suzuki Hideto Minami Masayoshi Okubo 《Colloid and polymer science》2008,286(13):1561-1567
Hollow polymer particles with multiple holes in the shell were prepared by aqueous microsuspension polymerization of micrometer-sized,
monodisperse divinylbenzene/n-hexadecane droplets in the presence of sodium dodecyl sulfate (SDS) at concentrations above 4 mM utilizing the Self-assembling Phase-Separated Polymer (SaPSeP) method developed by the authors. The total surface area of the holes per particle increased with an increase
in the SDS concentration. At [SDS] = 10 mM, “flower-like” non-spherical particles were formed.
Part CCCXV of series “Studies on Suspension and Emulsion” 相似文献
70.
Recently, cobalt (Co) is reported to be taken as a supplement by athletes for improving anaerobic performance. For the diagnosis of abuse, the limit of detection (LOD) of Co in the analysis should be lower than the concentrations of Co in plasma and urine of normal persons. A simple, rapid and sensitive method has been developed for the determination of Co in urine. Co was complexed with diethyldithiocarbamate (DDC) and extracted with isoamyl alcohol in the presence of citric acid. The detection of Co was achieved by injecting a 1-μL aliquot of isoamyl alcohol containing Co-DDC complex directly into an electrospray ionization tandem mass spectrometric (ESI-MS-MS) instrument without chromatographic separation. The quantification was performed using selected reaction monitoring at m/z 291 of the product ion Co(C4H10NCS)2+ which was produced by collision-induced dissociation from the precursor ion Co(DDC)2+ at m/z 355. ESI-MS-MS data were obtained in less than 10 min with an LOD of 0.05 μg L−1 and a linear calibration range of 0.1-100 μg L−1 using 10 μL of urine. The procedure was validated with certified reference materials (SRM 2670a and SRM 1643e). This method is suitable for the analysis of Co in the laboratories already equipped with an ESI-MS-MS instrument. 相似文献