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71.
Efficient optical phase-conjugate (PC) signals in four kinds of novel polyester films containing cyanoazobenzene units in the side chain are reported. One of them can efficiently generate only the photoinduced anisotropy (PA) component of PC signal, while the other three films can simultaneously generate two types of PC signals, PA and holographic components. These polymers have good potential not only as a phase conjugator but also as a polarization-sensitive hologram-recording material.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994 相似文献
72.
Hirofumi Osada 《Communications in Mathematical Physics》1996,176(1):117-131
We construct infinite-dimensional Wiener processes with interactions by constructing specific quasi-regular Dirichlet forms. Our assumptions are very mild; accordingly, our results can be applied to singular interactions such as hard core potentials, Lennard-Jones type potentials, and Dyson's model. We construct nonequilibrium dynamics.Dedicated to Professor Masatoshi Fukushima on his 60th birthday 相似文献
73.
Cationic liposomes enhanced firefly bioluminescent assay of bacterial ATP in the presence of an ATP extractant. 总被引:1,自引:0,他引:1
Naohiro Nakata Akihiko Ishida Hirofumi Tani Tamio Kamidate 《Analytical sciences》2003,19(8):1183-1185
Cationic liposomes composed of two components, diethylaminoethyl-carbamoyl cholesterol and phosphatidylcholine, were applied to an enhancer for a firefly bioluminescent (BL) assay of bacterial ATP in the presence of an ATP extractant. Trichloroacetic acid (TCA), which inhibits the activity of luciferase, was used as an ATP extractant. Cationic liposomes enhanced the BL intensity as long as luciferase was active. The detection limits for cell numbers of Escherichia coli extracts in the presence of cationic liposomes and in water alone were 199 and 897 colony forming units ml(-1), respectively. The sensitivity for bacterial ATP in the presence of cationic liposomes was improved by a factor of 2.5 times compared to that in the presence of diethylaminoethyl-dextran. 相似文献
74.
Nobuhiro Kawatsuki Ryoji Tsutsumi Akie Hiraiwa Hirofumi Takatsuka Takeya Sakai 《Journal of polymer science. Part A, Polymer chemistry》2008,46(14):4712-4718
Thermally enhanced photoinduced in‐plane molecular reorientation in new photo‐cross‐linkable polymer liquid crystalline (PPLC) films comprising 4‐[ω‐(4‐methoxycinnamoyloxy)alkyloxy]biphenyl side groups is explored using linearly polarized ultraviolet (LPUV) light exposure and subsequent annealing. The influence of the alkylene spacer length between the photo‐cross‐linkable group and the biphenyl mesogenic moiety is investigated. The straight‐line characteristics of the photoreactive mesogenic side group and the 4‐methoxycinnamoyl group play important roles in the high photoreactivity and the large thermally enhanced molecular reorientation, where the in‐plane order and the birefringence of the reoriented film are 0.61 and 0.18 are obtained. Finally, cooperative molecular reorientation of dichroic dyes doped in PPLC films is also achieved to fabricate a linear polarizer. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4712–4718, 2008 相似文献
75.
Firefly bioluminescence (BL) was greatly affected by cationic surfactants coexisting with liposomes containing phosphatidylcholine and cholesterol. In this study, the effects of the type and concentration of cationic surfactants on BL were studied in the presence of the liposomes. Three types of cationic surfactant: benzalkonium chloride (BAC), n-dodecyltrimethylammonium bromide (DTAB), and benzethonium chloride (BZC), were used. As a common effect in these surfactants, BL intensity was increased and then drastically decreased with increasing surfactant concentration. This can be explained by the formation of cationic liposomes as BL enhancers at low concentration of the surfactant, and by the transformation into cationic (mixed) micelles as inhibitors at high concentration. The maximal BL intensity and the concentration for the maximal BL were dependent on the type of the surfactants. To explain the differences in these parameters in the enhanced BL, we determined the distribution coefficient, K, of the surfactants to the liposomal membrane. The result indicated that the surfactant with higher K value gives the maximal BL intensity at lower concentration. 相似文献
76.
Shinjiro Hayakawa Yuki Hajima Shan Qiao Hirofumi Namatame Takeshi Hirokawa 《Analytical sciences》2008,24(7):835-837
Ca K edge X-ray absorption fine structure (XAFS) spectroscopy was utilized for the characterization and quantification of calcium carbonate polymorphs and their mixtures. The advantage of the XAFS is the small sample quantity required for measurements, and a flexible sample environment. The near-edge XAFS spectra of calcite, aragonite and vaterite were measured with the conversion electron yield (CEY) method, and the obtained spectra showed characteristic features that can be utilized as fingerprints. The quantification of mixed polymorphs was examined by using a linear combination fitting of reference XAFS spectra. Though the quality of the fits was satisfactory, discrepancies in the evaluated values were observed between those with X-ray diffraction (XRD) and XAFS. The nonuniformity of samples may be enhanced by the surface sensitivity of the CEY method. 相似文献
77.
Tamotsu Fujisawa Toshio Sato Tatsuo Kawara Masatoshi Kawashima Hirofumi Shimizu Yasuhiro Ito 《Tetrahedron letters》1980,21(22):2181-2184
Various organocuprates react with β-propiolactones to give β-substituted propionic acids in high yields. 相似文献
78.
79.
80.
Hirofumi Kawazumi Takayuki Oomori Naoki Yamani Teiichiro Ogawa 《Chemical physics letters》1984,106(4):351-353
The 1B2u-1A1g fluorescence emission of benzene excited by controlled electron impact was measured in the 14 – 100 eV region. The optically forbidden 6° levels were preferentially, excited. This indicates that a non-dipole transition takes place under low-energy electron-molecule collisions. 相似文献