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991.
Y. Matsuda 《Applied magnetic resonance》2003,23(3-4):469-480
Hydrogen atoms are encapsulated in octasilsesquioxane, R(SiO1.5)8, by irradiation with γ-rays at room temperature. In deca- and dodecasilsesquioxane, hydrogen atoms are encapsulated by irradiation at 77 K. The thermal decay of the encapsulated hydrogen is well described by a single-exponential function. The excitation energies of the decay are 110–117, 50.4, and 55.6 kJ/mol for the hydrogen atoms in Q8M8, Q10M10, and Q12M12, respectively. Theg-values and hyperfine splitting (hfs) constants of the hydrogen atoms in R(SiO1.5)8 are dependent on the substituents in the corners of the polyhedra, R. Theg-values are independent of the temperatures, while the hfs constants increase as the temperature decreases. Theg-values of the hydrogen atoms in a large encapsulating cavity decrease with increasing cavity size and approach 2.0023. The temperature dependence of the hfs constants for the hydrogen atoms in Q10M10 or Q12M12 suggests that the hydrogen atoms are localized within the encapsulating cages at low temperatures. 相似文献
992.
Improvement in reliability of probabilistic test of significant differences in GeneChip experiments.
Kyoko Toda Seiichi Ishida Kotoko Nakata Rieko Matsuda Yukari Shigemoto-Mogami Shogo Ozawa Jun-ichi Sawada Yasuo Ohno Kazuhide Inoue Koichi Shudo Yuzuru Hayashi 《Analytical sciences》2004,20(4):731-733
A probabilistic test (FUMI theory) for GeneChip experiments has been proposed for selecting the genes which show significant differences in the gene expression levels between a single pair of treatment and control. This paper describes that the reliability of the judgment by the FUMI theory can be enhanced, when the selected genes are referred to biomolecular-functional networks of a commercial database. The genes judged as being differently expressed are grouped into a cluster in the biomolecular networks. It is also demonstrated that false positive genes have a trend in the networks to be isolated from each other, and also away from the clustered genes, since the false positive genes are randomly selected. 相似文献
993.
Hideo Furuhashi Ryota Sugiyama Yoshiyuki Uchida Kiyofumi Matsuda Chander P. Grover 《Optical Review》2005,12(2):109-114
A new optical phase measurement method using a differentiation filter is proposed. The new method uses two images obtained by shifting the filter. This method has an advantage in that non-uniformity of the wavefront intensity does not produce errors. We present herein the theory of the newly proposed method and verify the theory by computer simulation. The effects of non-uniformity of the wavefront intensity, noise, and bias shifting length for errors are discussed. The system has been demonstrated for a plane wave and a spherical wave. For the proposed method, although the number of errors due to noise increases, the number of errors due to non-uniformity decreases. Therefore, the proposed method is useful for the phase measurement of a wavefront for which the intensity is not uniform. In addition, it improves the accuracy of the phase measurement system using a differentiation filter. 相似文献
994.
Formation of Anatase Nanocrystals-Precipitated Silica Coatings on Plastic Substrates by the Sol-Gel Process with Hot Water Treatment 总被引:3,自引:0,他引:3
Matsuda Atsunori Matoda Tatsuo Kogure Toshihiro Tadanaga Kiyoharu Minami Tsutomu Tatsumisago Masahiro 《Journal of Sol-Gel Science and Technology》2003,27(1):61-69
Anatase nanocrystals-precipitated silica coatings were formed on plastic substrates such as poly(ethylene terephtalate) (PET), acrylic resin (AC) and polycarbonate (PC) from silica-titania gel coatings with and without addition of poly(ethylene glycol) (PEG) by hot water treatment. The maximum thickness of the coatings which can be formed without cracking or peeling-off was 100 to 200 nm for PET and PC substrates, whereas it was less than 50 nm for AC substrates. After a hot water treatment at 90°C for 120 min, the size of the anatase nanocrystals increased to be 30 and 50 nm for the coatings obtained with and without PEG, respectively. Anatase nanocrystals were formed throughout the whole of the coatings obtained with PEG and were formed only on the surface of the coatings obtained without PEG. Both coatings obtained with and without PEG were highly transparent. The plastic substrates with coatings obtained without PEG showed good weathering resistance owing to the protective effects of the residual silica under-layer. The coatings obtained with PEG showed higher photocatalytic activities than those obtained without PEG due to smaller size and higher dispersion of anatase nanocrystals in the coatings. 相似文献
995.
Qingbin Xue Tatsumi Kimura Takashi Fukuda Satoru Shimada Hiro Matsuda 《Liquid crystals》2004,31(2):137-143
Chiral helical polymers have been expected to exhibit optical activity with a significantly large optical rotation power. In this paper polymethylphenylethylcarbodiimides (Poly-PhEMCDI) with helical structure were synthesized by the insertion polymerization of a corresponding chiral monomeric carbodiimide initiated by a copper complex. The circular dichroism spectra and optical rotation power induced by the ordered rigid main chain helical structure of polycarbodiimides, in solution and as cast films, were studied. Polycarbodiimides have a rigid rod helical structure and form lyotropic liquid crystal (LLC) in organic solvents such as dichloromethane (DCM), chloroform and THF. The LLC phase was studied using polarizing optical microscopy and X-ray diffraction. A chiral nematic phase was formed in DCM and chloroform in the concentration range 20-36%. Spherulites were formed in more concentrated solution. The formation of a LLC phase in polycarbodiimides organic solutions makes it possible to align the polymer helical chain to form an ordered film for electro-optical applications. 相似文献
996.
Jun Zhong Zhimei Qi Han Dai Chunhai Fan Genxi Li Naoki Matsuda 《Analytical sciences》2003,19(5):653-657
DNA and gold nanoparticles are co-immobilized at a gold electrode through elaborate self-assembly processes. This configuration has proven to be useful as a sensor for phenothiazine drugs, taking advantage of the well-known, relatively large surface area of gold nanoparticles and the strong intercalation between dsDNA and phenothiazine drugs. This modified electrode has demonstrated good sensitivity and stability towards the oxidation of two model phenothiazine drugs: promethazine and chlorpromazine. A linear dependence between the concentration of phenothiazine drugs and the peak current is observed, with a concentration range of 2.0 x 10(-5)-1.6 x 10(-4) M and 1.0 x 10(-5)-1.2 x 10(-4) M, and a detection limit of 1.0 x 10(-5) M and 7.0 x 10(-6) M, for promethazine and chlorpromazine, respectively. 相似文献
997.
Y. Hatsukawa T. Hayakawa K. Furutaka H. Nakada M. Kidera T. Ishii M. Matsuda M. Oshima S. Mitarai M. Sugawara H. Kusakari T. Komatsubara K. Furuno 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(1):3-4
The study of high spin states in 100Pd has indicated the presence of both single particle and collective states. More than twenty new transitions have been observed. A substantial modification and extension of the existing level scheme is proposed. The negative parity states can be understood in terms of collective excitations of the core coupled to the 9? and 5? bandheads, which are probably based upon two quasineutron ν(h11/2,g7/2) and two quasiproton π(g9/2,p1/2) configurations respectively. 相似文献
998.
Takeo Yamaguchi Bao‐Guo Wang Eriya Matsuda Shigejiro Suzuki Shin‐Ichi Nakao 《Journal of Polymer Science.Polymer Physics》2003,41(12):1393-1400
The relationship between polymer side‐chain length and the hole free volume that is effective for solvent diffusion was investigated for polyacrylates and polymethacrylates on the basis of free‐volume theory. Measurements of a polymer's viscoelasticity and solvent diffusivity provided experimental evidence for polymer segment mobility, and the results indicated that hole free volume in a linear polymer increases with hydrocarbon side‐chain length. Because the molecular mechanisms of polymer viscoelasticity and diffusivity are identical, the free‐volume parameters obtained for polyacrylates and polymethacrylates by measuring the polymer viscoelastic‐temperature dependence can reliably be used in predicting the solvent diffusion coefficient. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1393–1400, 2003 相似文献
999.
T. Shizuma Y. Toh M. Oshima M. Sugawara M. Matsuda T. Hayakawa M. Koizumi A. Osa Y.H. Zhang Z. Liu 《The European Physical Journal A - Hadrons and Nuclei》2003,17(2):159-165
Excited states in 187Re populated by inelastic scattering of a 500 MeV 82Se beam have been studied by means of in-beam γ-ray spectroscopy. Levels built on the 5/2+[402] and 9/2-[514] one-quasiparticle states were measured up to I
π = (21/2+) and (21/2-), respectively. In addition, several new levels including an isomer at 1682 keV with a half-life of 114(23) ns have been
found. Quasiparticle configurations of the levels and the transition rates are discussed.
Received: 12 December 2002 / Accepted: 13 March 2003 / Published online: 13 May 2003 相似文献
1000.
By introducing a cathode lens below or inside the objective lens of a scanning electron microscope, many experiments similar to those typical of the LEEM method can be performed. The conditions for the diffraction of slow electrons are modified by the convergence of the primary beam, and challenges include the necessity of managing the signal species propagating along the optical axis in a direction opposite to that of the primary beam. However, even a simple implementation, providing the integral dark-field signal only, has not only delivered plenty of results in the very low energy range below 50 eV, but the performance in the range of hundreds of eV and units of keV has also been substantially improved. The scanning LEEM method is illustrated using experimental results acquired by additionally employing multichannel detection and detection of transmitted electrons. 相似文献