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排序方式: 共有1359条查询结果,搜索用时 11 毫秒
71.
Takashi Aoki Yasuhiro Kombu Yasuo Ohno 《Proceedings of the American Mathematical Society》2008,136(2):387-395
A generating function for specified sums of multiple zeta values is defined and a differential equation that characterizes this function is given. As applications, some relations for multiple zeta values over the field of rational numbers are discussed.
72.
Koichi Aoki Mengjuan Li Jingyuan Chen Toyohiko Nishiumi 《Electrochemistry communications》2009,11(2):239-241
Water droplets were formed spontaneously at the interface of the 2-nitrophenyloctyl ether and aqueous phases on the oil phase side when the oil contained tetraalkylammonium chloride without surfactants. The droplets, less than some micrometers in diameter, gathered at the interface. The number density of the droplets was proportional to the concentration of tetraethylammonium chloride, and hence this salt should be responsible for the formation of the droplets as a surfactant. When positive voltage was applied to the aqueous phase against the oil, the droplets departed from the interface toward the oil bulk. The droplets should be negatively charged by chloride. The adsorption model of the salt was suggested, in which chloride is immobilized at the interface on the aqueous side electrostatically with tetraethylammonium ion on the oil side. 相似文献
73.
Eiji Hashimoto Yuichi Seshimo Keita Sasanuma Yuichiro Aoki Hitoshi Kanazawa Yuji Ike Seiji Kojima 《Journal of Thermal Analysis and Calorimetry》2010,99(1):45-50
The fragility of ethylene glycol and glucose aqueous solution systems has been investigated by temperature-modulated differential
scanning calorimetry (TMDSC). The frequency and temperature dependences of complex specific heat have been observed in the
vicinity of a glass-transition temperature T
g
. It is shown that the value of the fragility index m can be determined from the temperature dependence of the α-relaxation times observed by TMDSC. We have also studied the elastic
properties of these aqueous solutions by micro-Brillouin scattering, and determined these relaxation times of elastic properties
in the gigahertz range. 相似文献
74.
Yoshiro Kaneko Dr. Kazuya Fujisaki Tsuyoshi Kyutoku Hidemitsu Furukawa Dr. Jun‐ichi Kadokawa Prof. 《化学:亚洲杂志》2010,5(7):1627-1633
In this paper, we describe the preparation of hydrogels through the formation of an inclusion complex of amylose in a vine‐twining polymerization. This is achieved by the phosphorylase‐catalyzed polymerization of α‐D ‐glucose 1‐phosphate from maltoheptaose primer, in the presence of a water‐soluble copolymer having hydrophobic graft‐chains (poly(acrylic acid sodium salt‐graft‐δ‐valerolactone)). The mixture turns into a gel during the polymerization process. Evaluation of the hydrogels is conducted by shear‐viscosity measurements of the products. For the hydrogels with relatively high viscosities, fast relaxation modes of the cooperative diffusions are observed by scanning microscopic light scattering measurements, which indicate the nanometer‐size network structures of the hydrogels. In addition, we found that the enzymatic disruption and reproduction of the hydrogels are achieved by the combination of the amylase‐catalyzed hydrolysis of the amylose component and the formation of amylose by the phosphorylase‐catalyzed polymerization. 相似文献
75.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Angerami A Aoki K Apadula N Aphecetche L Aramaki Y Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Basye AT Bathe S Batsouli S Baublis V Baumann C Bazilevsky A Belikov S Belmont R Bennett R Berdnikov A Berdnikov Y Bhom JH Bickley AA Blau DS Boissevain JG Bok JS Borel H Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Camacho CM 《Physical review letters》2011,107(14):142301
We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200 GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2相似文献
76.
We studied the quantum interference of electrons in the Bi (p(x), p(y)) orbital-derived j = 1/2 spin-split surface states at Bi/Ag(111)√3 × √3 surfaces of 10 monolayer thick Ag(111) films on Si(111) substrates. Surface electron standing waves were observed clearly at the energy (E) below the intersection of the two spin-split downward dispersing parabola bands (E(x)). The E dependence of the standing wave pattern reveals the dispersion as the average of the two spin-split surface bands due to the interference between |(k + Δ), ↑> and |-(k - Δ), ↑> [or (|(k - Δ), ↓>) and |-(k + Δ), ↓>] states. In contrast, it was impossible to deduce the dispersion from the standing wave pattern at E ≥ E(x) because the surface electron cannot find its backscattered state with the same spin polarization. 相似文献
77.
The pressure-induced disproportionation reaction of LaH2 was investigated by infrared reflection and Raman measurements at ambient temperature. The relative reflection intensity in the 4000-6000 cm−1 region began to decrease significantly at a pressure of about 12 GPa and fell to 10% of the initial value at 20 GPa. Absorption peaks, which appeared around 1200 and 700 cm−1 at pressures above 14 GPa, were assigned to the hydrogen vibrations at the tetrahedral and octahedral sites of the fcc metal lattice, respectively. The peak frequencies measured in the 14-30 GPa range were similar to those observed in LaH3. These infrared results indicated insulating LaH3 precipitated from metallic LaH2. Above 20 GPa, a Raman peak related to the hydrogen vibration in the octahedral sites appeared around 700 cm−1, and was likely due to lattice distortion. The disproportionation reaction of LaH2 into and solid solution LaHx (x<1) was confirmed. 相似文献
78.
S. Aoki 《Progress in Particle and Nuclear Physics》2011,66(4):687-726
Progress on the potential method, recently proposed to investigate hadron interactions in lattice QCD, is reviewed. The strategy to extract the potential in lattice QCD is explained in detail. The method is applied to extract NN potentials, hyperon potentials and the meson–baryon potentials. A theoretical investigation is made to understand the origin of the repulsive core using the operator product expansion. Some recent extensions of the method are also discussed. 相似文献
79.
M. Tauseef Tanvir T. FujiiY. Aoki K. FushimiH. Habazaki 《Applied Surface Science》2011,257(19):8295-8300
For electrolytic capacitor application of the single-phase Ti alloys containing supersaturated silicon, which form anodic oxide films with superior dielectric properties, porous Ti-7 at% Si columnar films, as well as Ti columnar films, have been prepared by oblique angle magnetron sputtering on to aluminum substrate with a concave cell structure to enhance the surface area and hence capacitance. The deposited films of both Ti and Ti-7 at% Si have isolated columnar morphology with each column revealing nanogranular texture. The distances between columns are ∼500 nm, corresponding to the cell size of the textured substrate and the gaps between columns are 100-200 nm. When the porous Ti-7 at% Si film is anodized at a constant current density in ammonium pentaborate electrolyte, the growth of a uniform amorphous oxide film continues to ∼35 V, while it is limited to less than 6 V on the porous Ti film. The maximum voltage of the growth of uniform amorphous oxide films on the Ti-7 at% Si films is similar for both the flat and porous columnar films, suggesting little influence of surface roughness on the amorphous-to-crystalline transition of growing anodic oxide under the high electric field. Due to the suppression of crystallization to sufficiently high voltages, the anodic oxide films formed on the porous Ti-7 at% Si film shows markedly improved dielectric properties, in comparison with those on the porous Ti film. 相似文献
80.
G. Rajesh M. Arivanandhan H. Morii T. Aoki T. Koyama Y. Momose A. Tanaka T. Ozawa Y. Inatomi Y. Hayakawa 《Journal of Crystal Growth》2010,312(19):2677-2682
Dissolution process of GaSb into InSb melt was observed by an X-ray penetration method. The intensity of X-rays penetrated through the rectangular shaped GaSb (seed)/InSb/GaSb (feed) sandwich sample was recorded by the CdTe line sensor detector. The penetrated X-ray intensities and images of the sample were obtained as a function of time and temperature. The gallium (Ga) composition profile of the sample was calculated as a function of time by making the calibration line with the penetrated X-ray intensities of GaSb and InSb standard samples. The calculated Ga composition profile of the grown sample agreed well with the data measured by energy dispersive X-ray spectroscopy analysis. The result suggested that lower GaSb seed dissolved faster than upper GaSb feed despite of the low temperature at the lower GaSb seed. It clearly indicates that the solutal transport induced by gravity strongly affects the dissolution process. 相似文献