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51.
H. Kuboki H. Okuno A. Hershcovitch T. Dantsuka H. Hasebe K. Ikegami H. Imao O. Kamigaito M. Kase T. Maie T. Nakagawa Y. Yano 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(2):1029-1034
A differential pumping system with a Plasma Window (PW) has been developed for an application to a window-less He gas charge stripper. A PW with Southern Methodist University design was newly fabricated and tested off-line for evaluation of differential pumping efficiency. Switching gases for plasma seed from Ar to He was tested. It was found that the PW reduced the pressure at the first differential pumping section to 1/13 for Ar and to 1/17 for He, comparing with differential pumping without PW. At the second pumping section, the pressures were drastically reduced to 1/160 and to 1/4,520 for Ar and He, respectively. These pressure reduction factors indicate that one differentially pumped stage could be removed from a conventional differential pumping system. 相似文献
52.
Yokokita Takuya Yano Shinya Komori Yukiko Haba Hiromitsu 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):1127-1134
Journal of Radioanalytical and Nuclear Chemistry - To investigate sulfate complex formation of Rf, we performed batch-wise ion-exchange experiments of its homologues Zr and Hf and its pseudo... 相似文献
53.
Guoce Yu Shinichi Yano Hiroyuki Inoue Seiichi Inoue Jianlong Wang Takashi Endo 《Applied biochemistry and biotechnology》2014,174(6):2278-2294
Pretreatment-induced structural alteration is critical in influencing the rate and extent of enzymatic saccharification of lignocellulosic biomass. The present work has investigated structural features of rice straw pretreated by hot-compressed water (HCW) from 140 to 240 °C for 10 or 30 min and enzymatic hydrolysis profiles of pretreated rice straw. Compositional profiles of pretreated rice straw were examined to offer the basis for structural changes. The wide-angle X-ray diffraction analysis revealed possible modification in crystalline microstructure of cellulose and the severity-dependent variation of crystallinity. The specific surface area (SSA) of pretreated samples was able to achieve more than 10-fold of that of the raw material and was in linear relationship with the removal of acetyl groups and xylan. The glucose yield by enzymatic hydrolysis of pretreated materials correlated linearly with the SSA increase and the dissolution of acetyl and xylan. A quantitatively intrinsic relationship was suggested to exist between enzymatic hydrolysis and the extraction of hemicellulose components in hydrothermally treated rice straw, and SSA was considered one important structural parameter signaling the efficiency of enzymatic digestibility in HCW-treated materials in which hemicellulose removal and lignin redistribution happened. 相似文献
54.
Seawater bittern (nigari) is a concentrated solution remaining after the crystallization process of salt that has been used as a coagulant for tofu. Recently, various nigari products are distributed in the East Asia. To clarify the properties of nigari products, major mineral composition of six nigari products was determined. Then, effects of the nigari on the browning and antioxidant activity during the glucose/lysine Maillard reaction were investigated. Though the predominant cation was Mg2+, the content was varied by each product (0.88–6.49 mol/L). The other major ion contents were also varied. Each 0.5 mol/L of d-glucose and l-lysine were incubated with the nigari (5–50 % (v/v)) or nigari-related salts (1 or 2 mol/L). The browning (OD at 465 nm) and antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity and ferrous-reducing power) were increased remarkably by the nigari containing high Mg2+ content. The browning tended to be high with sulfates (Na2SO4, (NH4)2SO4). On the other hand, high content of MgCl2 decreased slightly the browning and antioxidant activity. These results suggest that the reaction and antioxidant activities were affected not only by salinity and cations but also by anions and other elements in the nigari. 相似文献
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Manabu KuroboshiTomotake Yano Shogo KamenoueHiromu Kawakubo Hideo Tanaka 《Tetrahedron》2011,67(32):5825-5831
Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode, wherein Al3+, which was electrogenerated at the anode would react as a Lewis acid with triphenylphosphine dichloride to afford tetra-coordinate chlorotriphenylphosphonium species and subsequent two-electron reduction at the cathode would give triphenylphosphine. One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide with oxalyl chloride and subsequent electroreduction. In a similar manner, some tetra-coordinate triphenylphosphonium species derived from triphenylphosphine oxide were reduced electrochemically to triphenylphosphine in moderate yields. 相似文献
59.
Jun Yano Akihiko Muta Yutaka Harima Akira Kitani 《Journal of Solid State Electrochemistry》2011,15(3):601-605
A poly(2,5-dimethoxyaniline) (PDMA) film was coated on the iron surface by the electropolymerization of 2,5-dimethoxyaniline in neutral buffer solution (pH?6.86). The PDMA film strongly adhered to the surface because of the polar methoxy groups of the PDMA molecules. The fact that no electrochemical response of the PDMA film-coated iron electrode to dissolved Fe2+ exhibited that the PDMA film was less permeable to dissolved species, acting as a diffusion barrier against agents causing corrosion such as H2O and O2. The PDMA film coating greatly lowered the anodic current peak ascribed to the anodic dissolution of iron and the corrosion current in strongly acidic medium, 0.5?M H2SO4 aqueous solution (1?M?????mol?dm??) as well as neutral medium (pH?6.86). The high anti-corrosion ability was due to a hybrid effect of the PDMA film not only as the diffusion barrier, but also as an in situ oxidant in spite of the slight redox activity of PDMA. In addition, the PDMA film is much more durable and adhesive than polyaniline film against over-oxidation. 相似文献
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