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41.
We estimated the energy barriers of proton transfers in the systems of (CF3SO3/H/SO3CF3)− and (CF3SO3/H/H2O/SO3CF3)− as models of a water-swollen Nafion membrane by an ab initio density functional quantum calculation method with consideration of the hydration effect. As a result, the proton transfer between the SO sites, which is accompanied by one water molecule, was found to be one of the proton-transfer mechanisms in the water-swollen Nafion membrane; that is, the surface diffusion mechanism was found to be important for the proton transfer in that membrane. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1905–1914, 2004 相似文献
42.
Kosaka T Yoneyama-Takazawa T Kubota K Matsuoka T Sato I Sasaki T Tanaka Y 《Journal of mass spectrometry : JMS》2003,38(12):1281-1287
We have developed a method for protein identification with peptide mass fingerprinting and sequence tagging using nano liquid chromatography (LC)/Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). To achieve greater sensitivity, a nanoelectrospray (nano-ES) needle packed with reversed-phase medium was used and connected to the nano-ES ion source of the FTICR mass spectrometer. To obtain peptide sequence tag information, infrared multiphoton dissociation (IRMPD) was carried out in nano-LC/FTICR-MS analysis. The analysis involves alternating nano-ES/FTICR-MS and nano-ES/IRMPD-FTICR-MS scans during a single LC run, which provides sets of parent and fragment ion masses of the proteolytic digest. The utility of this alternating-scan nano-LC/IRMPD-FTICR-MS approach was evaluated by using bovine serum albumin as a standard protein. We applied this approach to the protein identification of rat liver diacetyl-reducing enzyme. It was demonstrated that this enzyme was correctly identified as 3-alpha-hydroxysteroid dehydrogenase by the alternating-scan nano-LC/IRMPD-FTICR-MS approach with accurate peptide mass fingerprinting and peptide sequence tagging. 相似文献
43.
Synthesis and Rearrangement of P‐Nitroxyl‐Substituted PIII and PV Phosphanes: A Combined Experimental and Theoretical Case Study
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Tobias Heurich Dr. Zheng‐Wang Qu Dr. Senada Nožinović Dr. Gregor Schnakenburg Dr. Hideto Matsuoka Prof. Dr. Stefan Grimme Prof. Dr. Olav Schiemann Prof. Dr. Rainer Streubel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10102-10110
Low‐temperature generation of P‐nitroxyl phosphane 2 (Ph2POTEMP), which was obtained by the reaction of Ph2PH ( 1 ) with two equivalents of TEMPO, is presented. Upon warming, phosphane 2 decomposed to give P‐nitroxyl phosphane P‐oxide 3 (Ph2P(O)OTEMP) as one of the final products. This facile synthetic protocol also enabled access to P‐sulfide and P‐borane derivatives 7 and 13 , respectively, by using Ph2P(S)H ( 6 ) or Ph2P(BH3)H ( 11 ) and TEMPO. Phosphane sulfide 7 revealed a rearrangement to phosphane oxide 8 (Ph2P(O)STEMP) in CDCl3 at ambient temperature, whereas in THF, thermal decomposition of sulfide 7 yielded salt 10 ([TEMP‐H2][Ph2P(S)O]). As well as EPR and detailed NMR kinetic studies, indepth theoretical studies provided an insight into the reaction pathways and spin‐density distributions of the reactive intermediates. 相似文献
44.
In the present communication we would like to describe a novel method for the preparation of p-chloromethylstyrene and some reactions of this compound. 相似文献
45.
Abstract A memory type PDLC has been prepared by sandwiching a mixture of two-frequency-addressing liquid crystals and acrylate monomers with a hydoroxy group between two glass substrates with ITO electrodes followed by UV irradiation. This PDLC can be electrically switched between a transparent state and a light scattering state, which are maintained over several months without electric fields. 相似文献
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Yasuhiro Matoba Hiroshi Inoue Jun-Ichi Akagi Takuji Okabayashi Yasutaka Ishii Masaya Ogawa 《合成通讯》2013,43(9):865-873
Applicatims a Mo- and W-based heteropoly acids (HPA) as a catalyst in the oxidation of olefins have extensively been investigated1. However, a patent work is only attempted concerning the evoxidatim of olefins with H202 by HPA2) since the oxirane ring is cleaved because of a strong acidity of HPA itself. Herein, an effective epoxidatim of some allylic alcohols with H202 by a new Mo-species (MPCP), which was prepared from 12-molybdatophosphoric acid (H3PMo12040) and cetylpyridinium chloride (C5H5N (CH2), 15CH3- C1-) under two-phase conditions using chloroform as an organic solvent, is described. 相似文献
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50.
M. Matsuoka J. F. D. Chubaci J. P. Biersack S. Watanabe N. Kuratani K. Ogata 《辐射效应与固体损伤》2013,168(1-4)
Abstract Thin Ni films were prepared at room temperature by Ni metal vapour deposition and simultaneous irradiation by Ar ions with an energy of 2–20 keV. The reaction of Ni with Si during dynamic ion-beam mixing was studied. The fluences of the ion beam were 4.7 × 1017 and 8.9 × 1017 cm?2, and arrival rate ratios Ni/Ar were 9.7 and 5.1. Concentration profiles of Ni, Si, C, and O were analysed with Auger electron spectroscopy; the surface morphology and the crystalline structure were investigated with a cross-sectional scanning electron microscope and X-ray diffractometry. The theoretical profiles were calculated with the dynamic Monte Carlo simulation T-DYN for comparison with the experimentally obtained profiles. It was possible to observe the ballistic mixing effects and also thermally activated formation of nickel silicide. 相似文献