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111.
We have succeeded in video rate analysis of fringes stabilized by an active interferometer placed outside optical benches.
The interferometer uses the closed loop control of injection current of a laser diode to compensate for fringe movement that
is detected by a spatial filtering detector. A video image of the locked fringes with tilt is supplied to the real-time fringe
analyzer that delivers unwrapped phase distribution from the three phase shifted fringes generated by the electronic moiré
method. For a concave mirror of 130 mm diameter placed on a wooden desk we observed the repeatability of λ/60 for P-V surface
error of λ/5. 相似文献
112.
Hiroshi Tabata Kinya Kumazawa Masami Funakawa Jun-ichi Takimoto Makio Akimoto 《Optical Review》1996,3(2):139-145
This paper describes the mechanism generating the beautiful wing colors of various male butterflies and the relationship between the wing material and the color appearance. The microstructure of the scales covering the upper surface of the wings was analyzed with the aid of a scanning electron microscope. The basic mechanism of color generation of structurally colored scales is determined for the first time in accordance with the theory of optical interference in thin film layers using a model of wing scales. Optical properties were found in relation to the three-dimensional spectral reflectance of the samples, and differences were observed between the brightness perceived in subjective evaluations and calculated values based on the reflective spectra of the structurally colored wings. The results of this study suggest that the microroughness of the upper wing surface may influence the perceived gloss of structurally colored wings. 相似文献
113.
Yasumitsu Tamura Takayuki Yakura Jun-ichi Haruta Yasuyuki Kita 《Tetrahedron letters》1985,26(32):3837-3840
A short and efficient synthesis of dihydroxyacetone groups from keto groups involving the oxidation of ethynylcarbinol intermediates with [bis(trifluoroacetoxy) iodo] benzene (PIFA), is described. 相似文献
114.
The most sensitive metal reagents, water-soluble porphyrins with anionic side-chain, and cationic side-chain and their metal complexes were found to be associated by the surfactants with opposite charges and to be collected on membrane filters quantitatively. The ion-associates were dissolved in a few ml of H2SO4/DMF together with the filter paper, and the absorbance of the solution was readily measured. Concentration of 1/200 to 1/1000 of original volume was possible. Determination of 50 to 500 ng/1 level of copper ion will be presented. 相似文献
115.
Ikeda A Sato T Kitamura K Nishiguchi K Sasaki Y Kikuchi J Ogawa T Yogo K Takeya T 《Organic & biomolecular chemistry》2005,3(16):2907-2909
Various types of lipid membrane-incorporated C60 with high C60 concentrations can be prepared easily in several hours using the C60 exchange method and the photocleaving activity of cationic lipid membrane-incorporated C60 was appreciably higher than that of the C60.gamma-CDx complex. 相似文献
116.
Nagawa Y Suga J Hiratani K Koyama E Kanesato M 《Chemical communications (Cambridge, England)》2005,(6):749-751
A novel [3]rotaxane composed of two 25-membered crownophanes and one axle molecule having two anthryl end groups was successfully synthesized via covalent bond formation followed by aminolysis, and can incorporate caesium ion into the space between the two macrocycles as a 1 : 1 sandwich-type complex, whereas it makes a 1 : 2 complex with lithium ion. 相似文献
117.
Yamada Ji Satoki S Mishima S Akashi N Takahashi K Masuda N Nishimoto Y Takasaki S Anzai H 《The Journal of organic chemistry》1996,61(12):3987-3995
Efficient synthetic methods for the construction of a wide variety of unsymmetrical tetrathiafulvalenes (TTFs) via the Me(3)Al-promoted reactions of organotin thiolates or selenolates with esters are described. Reaction of tin thiolates (3a-c and 10) and selenolates (3d, 5, and 7) with esters (11a,b) in the presence of Me(3)Al as a Lewis acid gave dihydrotetrathiafulvalene derivatives (12, 14, 15, and 17-20) and 1,3-dithiane derivatives (13 and 16). In addition, the synthesis of diselenadithiafulvalene derivatives (25-28) could be accomplished by Me(3)Al-mediated reaction of tin thiolate (2a) or selenolates (3d and 5) with esters (22a, 22d, and 24). Furthermore, the application of the Me(3)Al-promoted reaction of tin thiolate (34) with esters (11a-b, 22a-d, and 35a-b) for the synthesis of unsymmetrical TTFs-fused donors enabled us to obtain various TTFs-fused systems (29-33) in short steps. 相似文献
118.
A new catalytic regioselective one-pot synthesis of hydroxyl-capped polyolefins is reported. This synthesis employs a new stereorigid bridged metallocene having an indenyl and a fluorenyl ligand named IF catalyst 1, exhibiting high catalytic performances. Here, we report on (1) the first example of allyl alcohol incorporation into the nonpolar polymer backbone using IF catalyst 1 and methylaluminoxane with high activity, high molecular weight, and high polar monomer uptake at high temperature, and (2) the first example of predominant end-site-selective introduction of an alcohol group into the polyolefins. Moreover, we observed the mixed regioselectivity by the type of alkylaluminum. 相似文献
119.
Jun-ichi TaniHiroyasu Kido 《Journal of solid state chemistry》2002,163(1):248-252
The geometrical and electronic structures of impurity (Cr, Mn, Co, Ni)-doped β-FeSi2 were investigated using first principles pseudopotential calculations based on generalized gradient approximation (GGA) density function theory. The calculated structural parameters depend strongly on the kinds of dopants and sites. The total energy calculations for substitution of dopants at the FeI and the FeII sites revealed that Mn prefers the FeI site, whereas Cr, Co, and Ni prefer the FeII site. The electronic structure is analyzed and discussed in terms of the atomic charges, bond overlap population, and total and partial densities of states (DOS). 相似文献
120.