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971.
Katsumi Matsuura Masamitsu Hirota Keizo Shimada Mamoru Mimuro 《Photochemistry and photobiology》1993,57(1):92-97
Spectral forms of bacteriochlorophyll (Bchl) in chlorosomes were analyzed by linear dichroism, circular dichroism (CD), and deconvolution of these spectra. Isolated chlorosomes were embedded in polyacrylamide gels and compressed unidirectionally (along the x-axis) while allowing the gel to stretch in another direction (along the z-axis). The chlorosomes were aligned three-dimensionally due to their flat oblong shape; the longest axis was presumed to parallel the z-axis, its shortest axis was presumed to parallel the x-axis, and the intermediate-length axis was presumed to parallel the y-axis. Degrees of polarization (AI? A1)/(AI+ A1) of Bchl c and a measured from the y-axis with linearly polarized light were significantly different from those measured from the x-axis. Deconvolution of spectra into components revealed the presence of two major forms of Bchl c with peaks at 744 nm and 727 nm. The degrees of polarization of the 744 and 727 nm spectral forms were 0.76 and 0.59 from the y-axis and 0.48 and 0.39 from the x-axis, respectively. The degrees of polarization of Bchl a794 were –0.21 from the y-axis and 0.12 from the x-axis. These values indicate that the direction of the Qy transition moment of Bchl c744 is almost completely parallel to the longest axis of chlorosomes and that of Bchl c727 is also nearly, but slightly less so, parallel to the longest axis of the chlorosomes. The Qy transition moment of the baseplate Bchl a peak at 794 nm is nearly perpendicular to the longest axis and parallel to the shortest axis: that is, it is perpendicular to the associated membrane plane in the cell. These alignments of Bchl transition moments in chlorosomes were lost after suspending the chlorosomes in a solution saturated with 1-hexanol accompanying a shift in the peak position from 742 nm to 670 nm. The alignment recovered after the hexanol concentration was decreased. The presence of two major spectral forms of Bchl c was supported by the deconvolution of CD spectra and absorption spectra. 相似文献
972.
973.
A.D. Martin T. Shimada R. Baldi T. Böhringer P.A. Dorsaz V. Hungerbühler M.N. Kienzle-Focacci M. Martin A. Mermoud C. Nef P. Siegrist 《Nuclear Physics B》1978,134(3):392-412
High statistics data for the reactions K±p → KS0π±p at 10 GeV/c are analysed. The K1(1?), K1(2+), and K1(3?) resonance parameters and production cross sections are calculated. The Kπ production amplitudes are determined as a function of t and the produced Kπ mass. Isoscalar natural-parity-exchange (NPE) is dominant. The t dependence of the K± NPE amplitudes have a cross-over at t = ?0.3 (GeV/c)2 for both K1(890) and K1(1420) production, being more pronounced for the K1(1420). Natural-parity-exchange interference effects are isolated. The NPE amplitudes are decomposed into pomeron-, f-, and ω-exchange contributions. S-wave Kπ production is found to be consistent with the Kπ partial-wave analyses of charge-exchange reactions. 相似文献
974.
975.
976.
Satoshi Seino Takuya Kinoshita Takashi Nakagawa Takao Kojima Ryoichi Taniguci Shuichi Okuda Takao A. Yamamoto 《Journal of nanoparticle research》2008,10(6):1071-1076
Composite nanoparticles consisting of gold and iron oxide were synthesized in aqueous solution systems by using a high-energy
electron beam. The electron irradiation induces radiation-chemical reaction to form metallic gold nanoparticles. These gold
nanoparticles were firmly immobilized on the surface of the support iron oxide nanoparticles. Surface of the support iron
oxide nanoparticles are almost fully coated with fine gold nanoparticles. The size of these gold nanoparticles depended on
the concentrations of gold ions, polymers and iron oxide nanoparticles in the solutions before the irradiation. 相似文献
977.
An assay method for pregnenolone and dehydroepiandrosterone in rat brains is developed using gas chromatography (GC)-electron ionization-mass spectrometry (MS)-MS. The extract of the rat brain homogenate containing deuterated internal standard with organic solvent is purified by silica gel minicolumn chromatography. The obtained fraction is derivatized into methyloxime, treated with dimethylisopropylsilylimidazole, and then subjected to GC-MS-MS. The method is applied to the determination of these steroids in the gray matter and olfactory bulbs of rat brains, which are divided into control and acute stressed specimens. Although pregnenolone in both regions of the rat brains increases more than three times after stress, dehydroepiandrosterone in both regions is not so clearly influenced by stress. 相似文献
978.
We have measured the transport properties of capacitively coupled one-dimensional arrays of small aluminum Josephson junctions. Under suitable biasing conditions, the samples act as current mirrors; the currents in the two arrays couple to each other and become equally large. The coupling is found both for currents flowing in the same direction and in opposite directions. We have also measured the time dependent fluctuations of the currents in the two arrays, and we find a strong correlation or anticorrelation of the fluctuations depending on the relative direction of the two currents. 相似文献
979.
M. Fujii N. Nishimura H. Fumon S. Hayashi K. Akamatsu T. Tsuruoka M. Shimada H. Katayama D. Kovalev B. Goller 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):193-196
Hydrophilic porous Si is prepared by surface modification with polyethylene oxide (PEO) molecules. The surface modification
is confirmed by infrared absorption spectroscopy and photoluminescence
spectroscopy. The effect of surface modification on the efficiency of photosensitization of oxygen molecules, i.e., the efficiency
of singlet oxygen generation, is studied. The PEO-terminated hydrophilic porous Si is shown to hold the photosensitization
ability although the efficiency is reduced by the modification. 相似文献
980.
D. Kameda H. Ueno K. Asahi D. Nagae M. Takemura K. Shimada A. Yoshimi T. Nagatomo T. Sugimoto M. Uchida T. Arai K. Takase S. Suda T. Inoue J. Murata H. Kawamura H. Watanabe Y. Kobayashi M. Ishihara 《Hyperfine Interactions》2007,180(1-3):61-64
The electric quadrupole moments for the ground states of 32Al and 31Al have been measured by the β ray-detected nuclear quadrupole resonance method. Spin-polarized 32Al and 31Al nuclei were obtained from the fragmentation of 40Ar projectiles at E/A?=?95 MeV/nucleon, and were implanted in a single crystal α-Al2O3 stopper. The measured Q moment of 32Al, |Q(32Al)|?=?24(2) mb, is in good agreement with a conventional shell-model calculation with a full sd model space and empirical effective charges, while that of 31Al is considerably smaller than the sd calculations. 相似文献