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171.
Nobuki Kashihara Heru Setyawan Manabu Shimada Yutaka Hayashi Chan Soo Kim Kikuo Okuyama Sugeng Winardi 《Journal of nanoparticle research》2006,8(3-4):395-403
Sine-wave modulated rf plasma has been used to control particle generation and growth in a plasma-enhanced chemical vapor deposition of silicon dioxide thin films using TEOS/O2. The density and the size of particles generated in the plasma are greatly reduced when the plasma is modulated with sine-wave modulation at low modulation frequency (<1000 Hz). In addition, particle contamination on the films is significantly reduced also for nanoparticles, and the film growth rates at the range of modulation frequencies where particle generation are greatly reduced do not decrease appreciably. Compared to its counterpart pulse-wave modulation plasma, the sine-wave modulation plasma has demonstrated a better performance in terms of reduction of particle generation and film contamination, and of film growth rate. Thus, the sine-wave modulation plasma has shown as a promising method to be applied in the production of thin film with a high deposition rate and a low particle contamination. 相似文献
172.
Laili Mahmoudian Jonas Melin Mohamad Reza Mohamadi Keiko Yamada Michio Ohta Noritada Kaji Manabu Tokeshi Mats Nilsson Yoshinobu Baba 《Analytical sciences》2008,24(3):327-332
We have developed a new method for a fast and precise analysis of circle-to-circle amplification (C2CA) product for specific gene detection by microchip electrophoresis. In this method, we have added a new enzymatic step to the C2CA reaction, which could be carried out isothermally at 37 degrees C. Compared to the original single-stranded DNA, the double-stranded DNA that is produced by this enzymatic reaction is more reliable for analysis by microchip electrophoresis. C2CA product was detected within 55 s with high reproducibility by this method which was successfully applied to the detection of 10-ng genomic DNA of the pathogenic bacteria Vibrio. cholerae within 110 s. Purification was found to be an indispensable step for the analysis of the C2CA product of genomic DNA samples. 相似文献
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For a given histogram, we consider an application of a simple rational spline to a shape preserving area true approximation of the histogram. An algorithm for determination of the spline is as easy as one with a quadratic polynomial spline, while the latter does not always preserve the shape of the histogram. Some numerical examples are given at the end of the paper. 相似文献
178.
Isolation of bufotalin 3-suberoyl-histidine and -3-methylhistidine esters from the skin of Schneider
Two novel bufotoxins, bufotalin 3-suberoyl-histidine and -3-methyl- histidine esters, were isolated from the skin of the Formosan toad, Schneider. 相似文献
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Masato Sakaguchi Hiromu Kinpara Yasuro Hori Shigetaka Shimada Hisatsugu Kashiwabara 《Journal of Polymer Science.Polymer Physics》1988,26(6):1307-1312
When poly(vinylidene fluoride) (PVDF) was ground with tetracyanoethylene (TCNE) powder in a vibration glass ball mill in vacuum in the dark at 77 K, the TCNE anion radical (TCNE-) was detected in the mixture by ESR spectroscopy. The TCNE.- is formed by the abstraction of electrons by TCNE from the anion that is produced by a heterogeneous bond scission of carbon-carbon bonds in the polymer main chain. The assignment of TCNE.- was carried out by the ESR spectral simulation on the basis of an anisotropic effective hyperfine tensor that includes a forbidden transition term. At least 85% of the bond scission of the PVDF main chain is induced by a heterogeneous process to produce ionic products. The yield of these mechanions seems to increase with the polarity of carbon-carbon bond owing to a substituent group bonded to the carbon in the polymer main chain. 相似文献