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31.
32.
Various N-cycloalkyl fumaramides having different characters of N-cycloalkyl groups such as piperidine, morpholine, or pyrrolidone were synthesized and homopolymerized or copolymerized with styrene by use of a radical initiator and ultraviolet irradiation, respectively. N,N′-Dipiperidinyl or -dimorpholyl fumaramides copolymerized with styrene to form a random copolymer, while N,N′-fumaroyl dipyrrolidone tended to form an alternating copolymer with styrene, indicating that the electron distribution of the N-cycloalkyl group affects the polymerizability of fumaramide derivatives. Photopolymerizability of these fumaramides was not as great as that of α,β-unsaturated esters. 相似文献
33.
34.
Ogata A. Nakajima K. Kozawa T. Yoshida Y. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1996,24(2):453-459
A conceptual design of a linac for pulse radiolysis is presented based on laser wakefield acceleration. Pulse radiolysis spectroscopically studies the initial stage of chemical reactions induced by electron beams. Single-bunched beams with a bunch-length on the order of a femtosecond are ideal for this purpose. The present design gives pure 20 pC single-bunches with an RMS bunch length of less than 10 fs. It accelerates and compresses only the head part of a high-current beam from a photocathode. Some practical problems concerning the design are also presented 相似文献
35.
Tokutaro Ogata 《Tetrahedron letters》2007,48(38):6648-6650
Asymmetric intramolecular cyclization of aminoalkenes was catalyzed by a catalytic amount of n-butyllithium, diisopropylamine, and a newly designed chiral bisoxazoline in toluene to produce kinetically controlled exo-cyclized amines with up to 91% ee quantitatively. 相似文献
36.
Tadahiro Minamikawa Seido Ogura Tetsuo Sakka Yukio Ogata Matae Iwasaki 《国际化学动力学杂志》1994,26(5):561-569
Photolysis of CClF2CH2Cl was studied by 147 nm vacuum ultraviolet irradiation. In the presence of NO; CF2CH2, CF2CHCl, and CClF2CN were produced. These products represent three different reaction paths; the molecular dechlorination, molecular dehydrochlorination, and chlorine radical elimination reactions. The reactant pressure and the addition gas (He or NO) pressure effects upon the product yield were studied. © 1994 John Wiley & Sons, Inc. 相似文献
37.
T. Ohshima M. Tanaka K. Katori M. Fujiwara H. Ogata M. Kondo N. Shimakura 《Hyperfine Interactions》1993,78(1-4):251-257
Nuclear polarization was measured by means of beam foil spectroscopy for a3He+ ion produced by an electron capture process of a3He2+ from a polarized sodium atom in an incident energy range from 20 to 28 keV. Assuming that a polarized electron of a sodium atom is predominantly captured to the 3d orbital of a3He+ ion andcascades down to the 1s ground state via the 2p orbital, an alignment factorA
0
col
(L=2) for the 3d orbital of a3He+ ion was extracted by comparing the observed initial sodium polarization andfinal nuclear polarization. The observedA
0
col
(L=2) showed a less pronounced energy dependence andwere qualitatively reproduced by the theoretical calculation. 相似文献
38.
Bingxin LiuYoshio Tatamitani Jun ShimadaTeruhiko Ogata 《Journal of Molecular Spectroscopy》2002,211(1):99-106
The microwave spectrum of the 35Cl and 37Cl isotopic species of 1-chloro-1,1,2-trifluoroethane (HCFC-133b) has been investigated in the frequency region 10 to 50 GHz using a Stark modulation microwave spectrometer. A pulsed jet Fourier transform microwave spectrometer was also used for the measurement of hyperfine splittings. A least-squares analysis of the observed b-type Q- and R-branch transition frequencies gave rotational and centrifugal distortion constants and components of the chlorine nuclear quadrupole coupling constant tensors in the principal axes system as follows: A=4625.161 (3) MHz, B=2004.127 (2) MHz, C=1875.813 (2) MHz, ΔJ=0.144 (9) kHz, ΔJK=1.0748 (8) kHz, ΔK=1.57 (1) kHz, δJ=0.01376 (4) kHz, δK=−0.146 (4) kHz, χaa=−57.958 (10) MHz, χbb=21.231 (11) MHz, and χcc=36.727 (11) MHz for 35ClCF2CH2F species, and A=4607.684 (6) MHz, B=1960.565 (2) MHz, C=1834.823 (2) MHz, ΔJ=0.106 (7) kHz, ΔJK=1.022 (3) kHz, ΔK=1.48 (1) kHz, δJ=0.0142 (2) kHz, δK=−0.18 (2) kHz, χaa=−46.268 (11) MHz, χbb=17.319 (13) MHz, and χcc=28.950 (13) MHz for 37ClCF2CH2F species. The structural parameters are calculated from the observed six rotational constants by assuming the partial structure of ab initio calculation. The electronic properties of the C-Cl bond are evaluated from the observed nuclear quadrupole constants of chlorine. These molecular properties are compared with those of other related molecules. 相似文献
39.
40.
Hidekatsu Yokoyama Toshiyuki Sato Tateaki Ogata Hiroaki Ohya-Nishiguchi Hitoshi Kamada 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,129(2):201-206
A signal detector of longitudinally detected ESR (LODESR) is independent of the resonant frequency. We developed anin vivoLODESR spectrometer operating in the regions of 300, 700, and 900 MHz. Using this apparatus, we estimated signal intensities at different operating frequencies obtained from non- or high-dielectric loss phantoms that contained nitroxide radical solutions and from live rats that had received a nitroxide radical. Our result, higher signal intensities in the high-dielectric loss samples (such as physiological saline solution and animals) at a lower frequency, shows that the influence of a decrease in dielectric loss dominates over the signal reduction caused by smaller Zeeman splitting. We believe that this finding strongly supports anin vivoESR resonant frequency that tends to be low. 相似文献