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261.
262.
Suttinart Noothongkaew Hideki Nakajima Anusorn Tong-on Worawat Meevasana Prayoon Songsiriritthigul 《Applied Surface Science》2012,258(6):1955-1957
Thermal oxidation of polycrystalline Zn foils at 5 × 10−7 Torr oxygen pressure and at room temperature, 50 °C, 70 °C, 90 °C and 110 °C was studied. In situ photoemission spectroscopy using synchrotron light with photon energy of 57 eV was used to monitor the formation of ZnO and to determine the thickness of the oxide overlayer. At the initial oxidation, the oxidation rate follows a two-stage logarithmic equation and later trends to saturate at a certain thickness depending on the oxidation temperature. The saturated thickness was found to increase with the oxidation temperature. The two-stage oxidation process may be governed by two kinds of space charge presumably formed in the thin oxide overlayer. 相似文献
263.
Tsutomu Furuta Toshihiro IsobeMunetoshi Sakai Sachiko MatsushitaAkira Nakajima 《Applied Surface Science》2012,258(7):2378-2383
During evaporation, shape changes of nanoliter-scale (80-100 nL) water droplets were evaluated on two superhydrophobic surfaces with different random roughness (nm-coating, μm-coating). The square of the contact radius and the square of the droplet height decreased linearly with evaporation time. However, trend changes were observed at around 170 s (nm-coating) and around 150 s (μm-coating) suggesting a wetting mode transition. The calculated droplet radii for the wetting mode transition from the average roughness distance and the average roughness height of these surface structures were approximately equal to the experimental values at these trend changes. A certain level of correlation between the roughness size and droplet radius at the wetting mode transition was confirmed on surfaces with random roughness. 相似文献
264.
Kentaro Kutsukake Hideaki Ise Yuki Tokumoto Yutaka Ohno Kazuo Nakajima Ichiro Yonenaga 《Journal of Crystal Growth》2012,352(1):173-176
We propose a simple numerical model for incorporation of oxygen and carbon impurities into multicrystalline Si during one-directional crystal growth in comparison with experimental results. The model includes parameters that are oxygen and carbon concentrations in the melt in the beginning of the growth, carbon flux form the atmosphere, oxygen fluxes from the crucible and to the atmosphere. Variation of oxygen and carbon concentrations in multicrystalline Si ingots with a diameter of 30 cm and a height of 7.5 cm solidified one-directionally was measured by infra red absorption spectroscopy at room temperature. By fitting the numerical results on the experimental results, the parameters were evaluated. In the modeling we found fruitful suggestions for suppressing and controlling the oxygen and carbon concentrations in multicrystalline Si for solar cells. 相似文献
265.
Fengming Chen Zhen Lin Yongzan Zheng Hulie Zeng Hizuru Nakajima Katsumi Uchiyama Jin-Ming Lin 《Analytica chimica acta》2012
In this work, an automatic multi-channel ink-jet for chemiluminescence (CL) analysis was developed. The four-channel ink-jet device was controlled by a home-made circuit. Differing from the classic flow injection CL, the whole procedure for CL analysis was automatically completed on a hydrophobic glass side. CL reaction of luminal and hydrogen peroxide for the determination of horseradish peroxidase (HRP) was selected as an application to automatic CL analysis platform. All solutions delivered by different channels were precisely ejected to the same position of the glass slide for the CL analysis. The consumption of reaction solution was reduced to nanoliter level. The whole CL analysis could be completed in less than 4 min, which was benefited from the prompt solution mixing in small size of droplet. The CL intensity increased linearly with HRP concentration in the range from 0.01 to 0.5 μg mL−1. The limit of detection (LOD) (S/N = 3) was 0.005 μg mL−1. Finally, the automatic CL system could also be used for the detection of HRP in HRP–protein conjugates, which showed its practical application in immunoassay. 相似文献
266.
Kazuhiko Tsukagoshi Miwa Otsuka Yukihiro Shikataand Riichiro Nakajima 《Journal of chromatography. A》2001,930(1-2):165-169
Peak areas, peak heights, and apparent theoretical plate numbers were examined as a function of sample injection times by use of the batch-type CL detection cell. Comparing the experimental data with those obtained by absorption detector, some considerations were carried out about the peak shape. The peak shape in CL detection was influenced by not only concentration distribution of sample in a sample zone but also sample diffusion and CL reaction at the capillary outlet. The sample injection time of ca. 35 s was recommended for the present CE with CL detector. The injection time much influenced peak shape as well as sensitivity in the CL detection cell. 相似文献
267.
Matthew T. Parsons Peter Westh James V. Davies Christa Trandum Eric C. H. To Wesley M. Chiang Eric G. M. Yee Yoshikata Koga 《Journal of solution chemistry》2001,30(11):1007-1028
The excess chemical potential, partial molar enthalpy, and volume of 1-propanol were determined in ternary mixtures of 1-propanol–glycerol–H2O at 25°C. The mole fraction dependence of all these thermodynamic functions was used to elucidate the effect of glycerol on the molecular organization of H2O. The glycerol molecules do not exert a hydrophobic effect on H2O. Rather, the hydroxyl groups of glycerol, perhaps by forming clusters via its alkyl backbone with hydroxyl groups pointing outward, interact with H2O so as to reduce the characteristics of liquid H2O. The global hydrogen bond probability and, hence, the percolation nature of the hydrogen bond network is reduced. In addition, the degree of fluctuation inherent in liquid H2O is reduced by glycerol perhaps by participating in the hydrogen bond network via OH groups. At infinite dilution, the pair interaction coefficients in enthalpy were evaluated and these data suggest a possibility that the interaction is mediated through H2O. 相似文献
268.
Haruhisa Nakajima 《manuscripta mathematica》2000,102(2):139-158
In order to inquire into invariants of non-semisimple groups, we introduce and study relative versions of equidimensionality
and stabilty, which are called relative quasi-equidimensionality and relative stability, of actions of affine algebraic groups,
especially of reductive groups, on affine varieties. As an application of our results, for complex reductive groups of semisimple
rank one, we characterize, respectively, relatively stable representations and relatively equidimensional representations
and, consequently, show that every equidimensional representation is cofree.
Received: 23 October 1998 相似文献
269.
We have developed a compact polytetrafluoroethylene (PTFE) assembly-type capillary electrophoresis with chemiluminescence (CL) detection system. Luminol-microperoxidase-hydrogen peroxide chemiluminescence reaction was adopted. The device is rectangular in shape (60 mm x 40 mm x 30 mm) and includes three reservoirs (sample, migration buffer, and detection reservoirs) with electrodes. The detection reservoir includes an optical fiber to transport light at the capillary tip to a photomultiplier tube. Isoluminol isothiocyanate (ILITC) was analyzed as a model using this device with fused-silica or polytetrafluoroethylene capillary tubes 10 cm in length. We also used the sample reservoir as a reactor for an immune reaction between anti-human serum albumin immobilized on glass beads and isoluminol isothiocyanate-labeled human serum albumin. The present polytetrafluoroethylene assembly with the capillary tube was useful as a palm-sized analysis device for separation and detection, as well as a reactor. 相似文献
270.