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171.
172.
A sodium ion-conducting polymer electrolyte based on polyvinyl pyrrolidone (PVP) complexed with NaClO4 was prepared using the solution-cast technique. The cathode film of V2O5 xerogel modified with polyvinyl pyrrolidone was prepared using the sol-gel method. Investigations were conducted using X-ray diffractometry (XRD), Fourier transformation infrared (FT-IR) spectroscopy. The ionic conductivity and transference number measurements were performed to characterize the polymer electrolyte for battery applications. The transference number data indicated that the conducting species in these electrolytes are the anions. Using the electrolyte, electrochemical cells with a configuration Na/(PVP + NaClO4)/V2O5 modified by (PVP) were fabricated and their discharge profiles studied.  相似文献   
173.
Nanoparticulate gold supported on a Keggin‐type polyoxometalate (POM), Cs4[α‐SiW12O40]?n H2O, was prepared by the sol immobilization method. The size of the gold nanoparticles (NPs) was approximately 2 nm, which was almost the same as the size of the gold colloid precursor. Deposition of gold NPs smaller than 2 nm onto POM (Au/POM) was essential for a high catalytic activity for CO oxidation. The temperature for 50 % CO conversion was ?67 °C. The catalyst showed extremely high stability for at least one month at 0 °C with full conversion. The catalytic activity and the reaction mechanism drastically changed at temperatures higher than 40 °C, showing a unique behavior called a U‐shaped curve. It was revealed by IR measurement that Auδ+ was a CO adsorption site and that adsorbed water promoted CO oxidation for the Au/POM catalyst. This is the first report on CO oxidation utilizing Au/POMs catalysts, and there is a potential for expansion to various gas‐phase reactions.  相似文献   
174.
In many countries, the labeling of grains, feed, and foodstuff is mandatory if the genetically modified (GM) organism content exceeds a certain level of approved GM varieties. We previously developed an individual kernel detection system consisting of grinding individual kernels, DNA extraction from the individually ground kernels, GM detection using multiplex real-time PCR, and GM event detection using multiplex qualitative PCR to analyze the precise commingling level and varieties of GM maize in real sample grains. We performed the interlaboratory study of the DNA extraction with multiple ground samples, multiplex real-time PCR detection, and multiplex qualitative PCR detection to evaluate its applicability, practicality, and ruggedness for the individual kernel detection system of GM maize. DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR were evaluated by five laboratories in Japan, and all results from these laboratories were consistent with the expected results in terms of the commingling level and event analysis. Thus, the DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR for the individual kernel detection system is applicable and practicable in a laboratory to regulate the commingling level of GM maize grain for GM samples, including stacked GM maize.  相似文献   
175.
郗迈 《大学物理》1999,18(5):26-28,34
运用光反馈的原理和技术演示并验证激光功率表达式,说明激光介质和光学谐振腔的性质和作用。  相似文献   
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177.
β-active probe nuclei are implanted in nominally undoped ZnSe crystals. β-radiation detected nuclear magnetic resonance (β-NMR) studies are described for two different probe nuclei, 8Li and 12B. This way, the implantation behavior of two “opposite”dopants, one acceptor (Li) and one donor (B) can be characterized by the same microscopic technique. Such characterizations are attempted in terms of the structure of intermediate or final lattice sites, defect charge states, or the kinetics of defect reactions and site changes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Teufel showed that total absolute curvature of a submanifold in a sphere or a hyperbolic space equals to the mean value of the number of critical points of level functions. This is an extension of the classical work of Chern and Lashof. In this paper we shall prove a similar result holds for the total absolute curvature of Kaehler manifold in a complex projective space. We shall also express the total curvature by the Euler numbers.The present research was supported by Grant in Aid for Scientific Research No. 5754005.  相似文献   
180.
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