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991.
Junpei Tsuji Kohki Ebitani Hideshi Hattori Hideaki Kita 《Reaction Kinetics and Catalysis Letters》1992,48(1):17-22
Infrared studies of adsorbed pyridine and OH groups on H-ZSM-5 zeolite demonstrate that protonic acid sites are generated on the surfaces by exposure to molecular hydrogen above 373 K. By evacuation of gas phase hydrogen, the protonic acid sites are eliminated.
, H-ZSM-5 373 . .相似文献
992.
Sadao Nishigaki Hashime Kanazawa Yukako Kanamori Misuzu Ichiba Keitaro Senga 《Journal of heterocyclic chemistry》1982,19(6):1309-1312
A new synthesis of certain pyrimido[5,4-e]-as-triazine 4-oxides and their ring transformation to pyrrolo-[3,2-d]pyrimidines by the 1,3-dipolar cycloaddition reaction is described. Thus, reaction of 6-hydrazino-1,3-dimethyluracil ( 1 ) with triethyl orthoformate gave 6-ethoxymethylenehydrazino-1,3-dimethyluracil ( 2 ). Treatment of 2 with arylamines gave 6-arylaminomethylenehydrazino-1,3-dimethyluracils ( 3a-e ). Nitrosative cyclization of 3a-e with sodium nitrite afforded 3-arylaminofervenulin 4-oxides ( 6a-e ). Reaction of 6a-e with acetylenic esters yielded 7-alkoxycarbonyl-6-arylamino-1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4(1H,3H-diones ( 15a-e and 16 ). 相似文献
993.
Hideaki Morita 《Advances in Mathematics》2007,212(1):277-292
We consider the Green polynomials at roots of unity. We obtain a recursive formula for the Green polynomials at roots of unity whose orders do not exceed some positive integer. The formula is described in a combinatorial manner. The coefficients of the recursive formula are realized by the cardinality of a set of permutations. The formula gives an interpretation of a combinatorial property on a family of graded modules for the symmetric group in terms of representation theory. 相似文献
994.
A new principle to measure the magnetic susceptibility of a solution was proposed; it utilized the displacement of solution surface caused by the magnetic force applied to the solution. The interfacial displacement was measured with the sensitivity of 5 nm from a change of the interference fringes, so called Newton Ring, generated from the solution surface and an upper surface of a small plano-convex lens on the bottom wall of a cell. The surface displacement measurement was carried out in a homemade cell attached by one or two small Nd-Fe-B magnets. The performance of this method was investigated by the measurements of magnetic susceptibility of manganese(II) chloride solution and some lanthanide(III) solutions. An excellent linear relationship between the magnetic susceptibility and the interfacial displacement was observed for each solution system. Then, it was demonstrated that this relationship could be used for the determination of the magnetic susceptibility of solutions or the concentration of a solute by using the manganese(II) solution as a standard solution. 相似文献
995.
Norimichi Tsumura Hideki Sato Takayuki Hasegawa Hideaki Haneishi Yoichi Miyake 《Optical Review》1999,6(1):57-61
A new technique is proposed to improve the way of selecting samples used to estimate spectral reflectance from sensor responses in multi-band images. This technique limits the samples of reflectance spectra based on the spectral reflectance estimated by the conventional estimation method, and estimates it again using the limited samples. Vector angle and distance among reflectance spectra as the criteria for the limitation can be applied to improve the estimation of reflectance spectra. 相似文献
996.
Hoang The Ban Hideaki Hagihara Kei Nishii Yasuo Tsunogae Shuichi Nojima Takeshi Shiono 《Journal of polymer science. Part A, Polymer chemistry》2008,46(22):7395-7400
This article reports an original method to control the birefringent property of the cyclic olefin copolymer, which has been recently commercialized as a new type of optical resins, via introduction of a third monomer that possesses a negative birefringence into the cyclic olefin copolymer that exhibits an inherently positive birefringence. The mutual compensation between these opposite‐sign birefringences effectively reduced the birefringent magnitude of the corresponding terpolymer. In fact, terpolymerization of norbornene (N), ethylene (E), and styrene (S), in which S exhibits a negative birefringence regarding to the positive birefringence of the NE copolymer was successfully prepared using fluorenylamidodimethyltitanium‐based catalyst, yielding NES terpolymers with controllable birefringent property. Especially, when the S content in the NES terpolymer was controlled at optimum values, it is possible to synthesize a new type of the cyclic olefin copolymer that exhibits an extremely low birefringent magnitude close to zero regardless of high degrees of chain orientation. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7395–7400, 2008 相似文献
997.
998.
Shigeki Kudo Takashi Mitsui Hideaki Sakai Hiroyuki Murata Masahiro Kanazawa 《Optical Review》2009,16(2):66-73
A new measuring technique that can measure retardation and can output magnitude and direction of plane stress in each glass
of a panel composed of double transparent pieces of glass has been developed using reflective confocal optics. The linear
polarized probe beam is incident to the glass and we can detect a reflected beam converted to orthogonal polarization caused
by the photoelastic phenomenon. Using the high extinction ratio (106) beam-displacing prism as a polarization discriminator, we can measure the photoelasticity by rotating the polarization of
the probe beam from 0 to π rad without disturbing the optical axis. This system has the ability to measure retardation. The lowest one is estimated
as nearly 0.066 nm for 700 μm thickness glass which corresponds to 0.03 MPa stress from our calibration line. 相似文献
999.
We present a mechanism depicting how a hydrogen atom migrates from a platinum catalyst to a Nafion membrane using ab initio calculations based on density functional theory (DFT). The H atom initially adsorbed on Pt is extracted by the sulfonate group (-SO3−), which is a part of the side chain of Nafion. We found partial electron transfer from the H atom to the Pt, which directly binds to the -SO3− group, through this reaction. The electron-poor H atom conducts in Nafion, and the partial electron transfer from the H atom results in the generation of electric power in polymer electrolyte fuel cells (PEFCs). 相似文献
1000.
Taiichiro Ida Hideaki Iwazaki Toshiyuki Omuro Yasushi Kawaguchi Yasuyuki Tsunoi Satoko Kawauchi Shunichi Sato 《Optical Review》2018,25(1):33-39
We previously launched a high-resolution photoacoustic (PA) imaging scanner based on a unique lensless design for in vivo skin imaging. The design, imaging algorithm and characteristics of the system are described in this paper. Neither an optical lens nor an acoustic lens is used in the system. In the imaging head, four sensor elements are arranged quadrilaterally, and by checking the phase differences for PA waves detected with these four sensors, a set of PA signals only originating from a chromophore located on the sensor center axis is extracted for constructing an image. A phantom study using a carbon fiber showed a depth-independent horizontal resolution of 84.0 ± 3.5 µm, and the scan direction-dependent variation of PA signals was about ± 20%. We then performed imaging of vasculature phantoms: patterns of red ink lines with widths of 100 or 200 μm formed in an acrylic block co-polymer. The patterns were visualized with high contrast, showing the capability for imaging arterioles and venues in the skin. Vasculatures in rat burn models and healthy human skin were also clearly visualized in vivo. 相似文献