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961.
Tomoharu Sakai Hiroyuki Nakagawa Shinya Kitagawa Hajime Ohtani 《Analytical sciences》2008,24(6):735-738
Dual-gradient capillary electrochromatography (DG-CEC) was developed to provide superior performance with regard to the separation of ionized analytes; in this method, both the eluent composition and the applied voltage are varied during the separation procedure. As for the gradient in the eluent composition, a shift in the pH is employed to control not only the electrophoretic mobility, but also the retention factor of the analytes. The dual-gradient method was shown to be effective in increasing the resolution and reducing the chromatographic period of ionized analytes. Fourteen kinds of o-phthalaldehyde labeled amino acids were separated within 8 min using DG-CEC with multistage enlargement in the applied voltage. The separation efficiency increased particularly for highly retained amino acids in the dual-gradient, as compared to those in the ordinary single-gradient for the eluent. 相似文献
962.
Tokuji Ikeda Hirosuke Tatsumi Hajime Katano Mizue Wanibuchi Takao Hibi Tsutomu Kajino 《Analytical sciences》2008,24(2):237-241
The thermal stability of a redox enzyme, bilirubin oxidase (BOD), has been quantitatively evaluated by measuring the inactivation kinetics of BOD at several temperatures. The enzyme activity is directly related to the mediated bioelectrocatalytic current for the BOD-catalyzed reduction of O(2). Thus, the inactivation process is measured by the time-dependent decrease in the bioelectrocatalytic current. The results reveal that the inactivation obeys first-order kinetics, whose rate constants (k) are determined at pH 7.0 and at 50 - 70 degrees C. The half life of BOD activity, calculated from the k value at 50 degrees C is 114 min, which is in harmony with the thermal-stability data given in a catalog by Amano Enzyme Inc. The bioelectrocatalysis method allows in situ measurements of the inactivation kinetics in the period of a few minutes at relatively high temperatures. The rate constants show a large temperature dependence, leading to a large Arrhenius activation energy (E(A)) of 221 kJ mol(-1). The activation Gibbs energy (DeltaG(not equal)), activation enthalpy (DeltaH(not equal)), and activation entropy (DeltaS(not equal)) are also determined. 相似文献
963.
Kazutoshi Nose Tatsuo Mizuno Norio Yamane Takaharu Kondo Hajime Ohtani Shuki Araki Takao Tsuda 《Analytical sciences》2005,21(12):1471-1474
Identifying and measuring the ammonia gas that emanates from human skin, which we called skin gas, has been achieved using a modified gas chromatographic system with a nitrogen-selective detector (flame-thermoionic detector: FTD). The skin gas is collected with a home-made sampling probe or bag, which is used to cover the skin surface of a subject's wrist, or a finger, for 5 min. It was proved that ammonia was present in skin gas for healthy persons and patients with hepatic disease. The average amounts of ammonia were 1.7 +/- 0.4 and 2.7 +/- 0.8 ng/cm2; furthermore, there was a significant difference between them (p < 0.05). In addition, the ammonia levels present in skin gas were correlated with that in blood (r = 0.64, p < 0.05). 相似文献
964.
Taro Ueda Takayuki Nagano Hajime Okawa Seiji Takahashi 《Electrochemistry communications》2009,11(8):1654-1656
An amperometric zirconia-based sensor attached with perovskite-type oxide sensing electrode was examined for monitoring NO2 in automobile exhaust. The sensor using La0.6Sr0.4Co0.98Mn0.02O3 showed high response to NO2. The response was almost linear to NO2 concentration in the range between 50 and 800 ppm, and a 90% reaction time to 400 ppm NO2 was less than 20 s. Though the NO2 response of the sensor was slightly affected by the changes in O2 concentrations, it showed still high response in the examined range of 5–21 vol%. 相似文献
965.
Hajime Moriya 《Journal of statistical physics》2018,172(5):1270-1290
We investigate dynamics of a supersymmetric fermion lattice model introduced by Nicolai (J Phys A 9:1497–1505, 1976). We show that the Nicolai model has infinitely many local constants of motion for its Heisenberg time evolution, and therefore ergodicity (with respect to thermal equilibrium states) breaks. It has infinitely many degenerated classical ground states. This phenomena is considered as localization at zero temperature. From a viewpoint of perturbation theory, we explain why delocalization is suppressed at zero temperature despite its disorder-free translation-invariant quantum interaction. 相似文献
966.
ABSTRACTWe have investigated conformational fluctuations in a new green fluorescent protein(GFP)-like protein rb-Akane found in a red-brown-colored octocoral, Scleronephthya gracillima (Kuekenthal)), with high pressure fluorescence spectroscopy at 0.1–700?MPa. Besides the green fluorescence at 510?nm, two red fluorescence peaks are observed at 590 and 629?nm, the relative intensity of which varies reversibly with pressure. The phenomenon is interpreted as representing the cis–trans isomerization of the chromophore accompanied by the conformational transition between two sub-states of the red fluorescence form of rb-Akane. The two sub-states are separated only marginally in free energy (ΔG0?=?1.9?±?0.4?kJ?mol?1), but significantly in partial molar volume (ΔV0?=??19.8?±?1.4?ml?mol?1) at 0.1?MPa (pH 7.5, 25°C). Above 500?MPa, the fluorescence at λmax 629?nm undergoes another reversible change with pressure, showing the onset of unfolding. 相似文献
967.
Akira Sasaki Atsushi Sunahara Hiroyuki Furukawa Katsunobu Nishihara Takeshi Nishikawa Fumihiro Koike Hajime Tanuma 《High Energy Density Physics》2009,5(3):147-151
We present the development of population kinetics models for tin plasmas that can be employed to design an EUV source for microlithography. The atomic kinetic code is constrained for the requirement that the model must be able to calculate spectral emissivity and opacity that can be used in radiation hydrodynamic simulations. Methods to develop compact and reliable atomic model with an appropriate set of atomic states are discussed. Specifically, after investigation of model dependencies and comparison experiment, we improve the effect of configuration interaction and the treatment of satellite lines. Using the present atomic model we discuss the temperature and density dependencies of the emissivity, as well as conditions necessary to obtain high efficiency EUV power at λ = 13.5 nm. 相似文献
968.
In [11] it was proved that, given a compact toric Sasaki manifold with positive basic first Chern class and trivial first
Chern class of the contact bundle, one can find a deformed Sasaki structure on which a Sasaki-Einstein metric exists. In the
present paper we first prove the uniqueness of such Einstein metrics on compact toric Sasaki manifolds modulo the action of
the identity component of the automorphism group for the transverse holomorphic structure, and secondly remark that the result
of [11] implies the existence of compatible Einstein metrics on all compact Sasaki manifolds obtained from the toric diagrams
with any height, or equivalently on all compact toric Sasaki manifolds whose cones have flat canonical bundle. We further
show that there exists an infinite family of inequivalent toric Sasaki-Einstein metrics on for each positive integer k. 相似文献
969.
Kiriyama H Mori M Nakai Y Shimomura T Tanoue M Akutsu A Kondo S Kanazawa S Okada H Motomura T Daido H Kimura T Tajima T 《Optics letters》2008,33(7):645-647
We report a high-contrast, high-intensity Ti:sapphire chirped-pulse amplification system that incorporates a nonlinear preamplifier based on optical parametric chirped-pulse amplification (OPCPA). By cooling the Ti:sapphire crystal in the final amplifier down to 77 K, the chirped-pulses are amplified to 2.9 J at a 10 Hz repetition rate without a thermal lensing effect. Pulse compression down to 19 fs duration obtained after amplification indicates a peak power of 80 TW. With the OPCPA, the temporal contrast is significantly improved to better than 7x10(-9) in a few picoseconds interval prior to the main laser pulse. 相似文献
970.
Mitsuhiro Hashimoto Kenji Miura Hiroaki Muraoka Hajime Aoi Roger Wood Michael Salo Yoshihiro Ikeda 《Journal of magnetism and magnetic materials》2008
The read/write characteristics of non-patterned media (NPM), discrete track media (DTM), and bit patterned media (BPM) are examined by modeling the magnetization distribution of NPM and patterning fluctuation of DTM. By comparing spin-stand measurement with calculation, the magnetization distribution of NPM was well characterized with a new Voronoi cell magnetic cluster model, in which the cluster size at the track edge, 〈Dedge〉, was larger than that at the track center, 〈Dcenter〉 by a factor of two. Based on an analysis of patterning fluctuations seen in SEM images of DTM, line-edge roughness (LER) was modeled as a long-wavelength center-line roughness (CLR) plus a short-wavelength line-width roughness (LWR). It was confirmed that the standard deviation of the patterning fluctuation was much smaller than that of the magnetic fluctuation for NPM. This allowed DTM to achieve higher off-track performance than NPM. By examining the 747 curves, it was revealed that DTM could have an advantage in track-density of up to approximately 25% assuming patterning fluctuations can be well controlled at high track density. In BPM, fabricating accurate dots is essential. The relationship between dot defect rate and patterning fluctuation was examined, and the maximum allowable standard deviation of LER was derived as 2 nm for achieving 1 Tbspi. 相似文献