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The synthesis and characterization of N,N'-p-xylylene-linked oligo-Janus [2]rotaxanes based on a permethylated alpha-cyclodextrin and their contractible and extendable nature coupled with photochromism are described. 相似文献
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This work examines the ozone electrogeneration(OE) at a binary coating of different nominal compositions(Pt)x-(TaOy)(100-x), where x(percentage in the precursor solution) varied between 1% and 100%, coated on titanium substrate prepared by a sol-gel technique. TheOE is performed in an artificial tap water at room temperature(25C). The percentages of Pt and TaOy in the coating significantly affect the electrocatalytic activity towards oxygen evolution. The oxygen evolution was retarded to a different extent based on the electrode composition. The largest retardation was obtained at the(Pt)10-(TaOy)90 electrode(ca. 480 m V positive shift) as compared with the(Pt)100-(TaOy)0 electrode.This was reflected in a high current efficiency(CE) ofOE(ca. 19.3%) at the former electrode. This value is considered to be among the highest values reported forOE at 25C in neutral media. The composite electrodes were characterized by voltammetric and surface techniques. A plausible explanation for the change of the efficiency ofOE with the electrode composition is given based on the electrochemical results. 相似文献
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Highly Efficient Dehydrogenative Coupling of Hydrosilanes with Amines or Amides Using Supported Gold Nanoparticles 下载免费PDF全文
Dr. Takato Mitsudome Teppei Urayama Dr. Zen Maeno Dr. Tomoo Mizugaki Prof. Dr. Koichiro Jitsukawa Prof. Dr. Kiyotomi Kaneda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3202-3205
Hydroxyapatite‐supported gold nanoparticles (Au/HAP) can act as a highly active and reusable catalyst for the coupling of hydrosilanes with amines under mild conditions. Various silylamines can be selectively obtained from diverse combinations of equimolar amounts of hydrosilanes with amines including less reactive bulky hydrosilanes. This study also highlights the applicability of Au/HAP to the selective synthesis of silylamides through the coupling of hydrosilanes with amides, demonstrating the first example of an efficient heterogeneous catalyst. Moreover, Au/HAP shows high reusability and applicability for gram‐scale synthesis. 相似文献
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Y. Ohuchi K. Tadatomo H. Nakayama N. Kaneda T. Detchprohm K. Hiramatsu N. Sawaki 《Journal of Crystal Growth》1997,170(1-4):325-328
Tetraethylsilane (TeESi) and bis(ethylcyclopentadienyl)Mg (ECp2Mg) were employed as Si and Mg dopant precursors for MOVPE growth of n-type and p-type GaN films, respectively. In Si doping, the electron concentration was observed to increase with the increase of the TeESi flow rate. The temperature dependence of the Hall mobility showed good agreement with n-type GaN films grown using different dopant precursors (SiH4, GeH4, Si2H6). The donor activation energy was estimated to be 27 meV, which is almost the same as the literature values. In Mg doping, we also found that the Mg concentration increases as the ECp2Mg flow rate increases. All of Mg-doped samples in this study showed p-type conduction after annealing. The acceptor activation energy was estimated to be 170 meV, which was close to the reported values. 相似文献
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Immobilization of glucose oxidase (GOD) within a hybrid mesoporous membrane with 12 nm pore diameter was successfully achieved, resulting in catalytically high efficiency during flow of a glucose solution across the membrane. 相似文献
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