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31.
Tsuji H Terada M Toshimitsu A Tamao K 《Journal of the American Chemical Society》2003,125(25):7486-7487
On the basis of the UV absorption spectra of the anti,cisoid alternating oligosilanes, the first experimental clear-cut evidence was presented for the generally accepted idea that the sigma conjugation in polysilanes does not effectively extend through a tetrasilane fragment with a small dihedral angle such as a cisoid turn. 相似文献
32.
Sugiura S Ichikawa S Sano Y Nakajima M Liu XQ Seki M Furusaki S 《Journal of colloid and interface science》2001,240(2):566-572
The formation of reversed micellar systems composed of phosphatidylcholine (PC) and fatty acid was newly demonstrated by a significant increase in water content in the organic ethyl oleate phase when the micelles were prepared by the contact method. The solubilized water concentration in the reversed micellar organic phase reached 3 wt%. The new systems are expected to be used as highly biocompatible reversed micellar systems. The structure of the reversed micelles composed of PC and oleic acid was characterized by determining the water concentration and by small-angle X-ray scattering analysis. The reversed micelles composed of PC and oleic acid formed in ethyl oleate were spherical. The radius of gyration was between 30 and 50 Å. The size of the reversed micelles decreased with an increase in the oleic acid concentration and was independent of the PC concentration. Experimental results indicated that the structure of the reversed micellar system was determined by the oleic acid concentration. An increase in the PC concentration caused an increase in the number of reversed micelles of the same size. These reversed micellar systems are expected to be used as solubilization media in pharmaceutical and food industries because they are not toxic. 相似文献
33.
New chiral stationary phases of polydimethylsiloxane anchored with (S)-(-)-t-leucine derivatives were provided for use in enantiomer separation of pharmaceuticals by capillary gas chromatography. Fifteen pharmaceuticals were separated into their enantiomeric pairs by converting them into pentafluoropropionyl and heptafluorobutyryl derivatives. The separation factor and resolution obtained from the new phases were superior to those from the conventional Chirasil-Val capillary column. 相似文献
34.
Velocity vector measurement by using fiber-optic low coherence interferometers is proposed and demonstrated. The interference outputs between the reference and backscattered light from the probing points in the flow are correlation processed. The probing points can be specified and are set on the x-, y-, and z-axis in the flow by using the fiber-optic low coherence interferometers. The direction (angles from each axis) and absolute value of the flow velocity can be measured from peak positions of correlations. 相似文献
35.
傅元勇 周书华T. Koike S. Kinoshita Y. Ma Y. Miura K. Miwa Y. Miyagi K. Shirotori T. Suzuki H. Tamura K. Tsukada M. Ukai K. Futatsukawa K. Hosomi M. Kawai M. Mimori N. Terada N. Maruyama K. Aoki H Fujioka Y Kakiguchi T. Nagae D. Nakajima H Noumi T Takahashi T.N. Takahashi A. Toyota M. Dairaku T. Fukuda S. Minami W. Imoto S. Aiimura K. Tanida 《中国物理快报》2007,24(8):2216-2218
From the ^12 C(π^+,K^+)^12 AC reaction the γ -rays of 261.6±0.24 ke V(7/2^+ →5/2^+)and 1481.7±0.7 ke V(1/2^+ →5/2^+) of ^11 A B,and 2667.3±2.8 keV(1^- 2 → 2^- 1)of ^12 A C hypernuclei have been identified using a large germanium detector array Hyperball2 at K6 beam line of KEK. The observed energies of the transitions 1481.7keV and 261.6 keV are significantly different from the values predicted by the shell model using the △ and SN parameters determined from the ^7 △ Li data. 相似文献
36.
(Z)-Propargylic oxime ethers derived from α,β-unsaturated aldehydes were converted to the corresponding 2,3,6-trisubstituted pyridine oxides in moderate to acceptable yields with high regioselectivity. The reaction proceeds via a tandem thermal [2,3] rearrangement, 4π electrocyclization, and ring expansion. 相似文献
37.
Yoichi Tanaka Yuji Taniguchi Daisaku Tanaka Masatoshi Toyoda Hideshi Ishii Teruo Tanabe Yasuko Terada Shinjiro Hayakawa Jun Kawai 《Analytical sciences》2005,21(7):839-843
The Kosa (yellow sand) aerosol affects the global environment as well as human health because it migrates from the interior of China to other areas, absorbing various atmospheric elements. Investigation into individual Kosa aerosol particles, which are submicroscopic to several tens of micrometers in diameter, is required to resolving the issue. We installed a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectrometer (EDX) on a synchrotron radiation (SR) beam line and introduced the SR beam into the SEM chamber for combinatorial application of SEM-EDX and SR X-ray fluorescence (SR-XRF) spectrometry to individual particles. It should be noted that detailed topographic observation by SEM and sensitive elemental analysis by SR-XRF, both crucial for individual particle measurement but which previously had to be carried out separately, were jointly performed inside the SEM chamber in this setup. Here, we show that SR-XRF results, in conjunction with SEM images, contributed toward resolving individual particle dispositions. Atmospheric sulfur primarily adheres to calcium in the aerosol particles and the particle surface roughens as a consequence of the chemical reaction between the two elements. 相似文献
38.
39.
Kayo Terada Toshio Masuda Fumio Sanda 《Journal of polymer science. Part A, Polymer chemistry》2009,47(19):4971-4981
Novel optically active ethynyl monomers were synthesized from L ‐valine and N‐methyl‐L ‐valine, and polymerized with a rhodium catalyst to provide the polymers with number‐average molecular weights over 200,000 in good yields. The CD and UV‐vis spectra of the polymers indicated that they took helical structures with predominantly one‐handed screw sense in solution. The polymers served as catalysts of asymmetric reduction of aromatic ketimines to afford optically active amines in moderate yields. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4971–4981, 2009 相似文献
40.