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41.
Masaki Matsui Yuya Tsuzuki Yasuhiro Kubota Kazumasa Funabiki Toshiyasu Inuzuka Kazuhiro Manseki Shinji Higashijima Hidetoshi Miura Hiroyasu Sato Tsukasa Yoshida 《Tetrahedron》2018,74(40):5867-5878
(2R,3aR,8bR)- and (2S,3aS,8bS)-2-Methyl indoline dye tetrabutylammonium carboxylates exhibited the highest conversion efficiency among four regio and stereo isomers. These indoline dyes also showed higher conversion efficiency than DN350. 相似文献
42.
Masahiro Mitsuyama Koichi Kondo 《Journal of polymer science. Part A, Polymer chemistry》2001,39(6):913-917
11‐Dodecyn‐1‐ol as an achiral, aliphatic, monosubstituted acetylene was copolymerized with cholesteryl 3‐butynyl carbonate as a chiral, aliphatic, monosubstituted acetylene with Rh(nbd)[B(C6H5)4] (nbd = norbornadiene) in tetrahydrofuran. The main chain of the obtained copolymers seemed to be mainly composed of the cis‐type structure. The backbone π–π* transition of these copolymers showed significant circular dichroism (CD), indicating an excess of one‐handed helical conformation. These CD signals were varied with the contents of the cholesteryl units in the copolymers. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 913–917, 2001 相似文献
43.
A model is presented for the potential distribution across a charged membrane. The membrane-fixed charges are assumed to be distributed through a surface layer of non-zero thickness on the membrane. We treat the surface layer as a different phase from the surrounding solution phase. The potential arises from the membrane-fixed charges and from different solubilities of positive and negative electrolyte ions in the two phases. Equations are presented for the potential distribution, which involve the partition coefficients of electrolyte ions and the relative permittivity of the surface layer. 相似文献
44.
Hesse-Ertelt S Witter R Ulrich AS Kondo T Heinze T 《Magnetic resonance in chemistry : MRC》2008,46(11):1030-1036
Solid-state (13)C-NMR spectroscopy was used to characterize native cellulose pellicles from two strains of Gluconacetobacter xylinus (ATCC 53582, ATCC 23769), which had been statically cultivated in Hestrin-Schramm (HS) medium containing fully (13)C-labeled beta-D-glucose-U-(13)C(6) as the sole source of carbon. For both samples, the (13)C-NMR chemical shifts were completely assigned for each (13)C-labeled site of cellulose I(alpha) with the aid of 2D refocused INADEQUATE NMR. To determine the principal chemical shift tensor components, a pulse sequence based on the recoupling of anisotropy information (RAI) was applied at 10 kHz MAS. The detailed (13)C tensors of cellulose I(alpha) from different bacterial celluloses are thus available now for the first time, and these results have been compared with previously published data of nonenriched material and with theoretical predictions. 相似文献
45.
A Permselective CeOx Coating To Improve the Stability of Oxygen Evolution Electrocatalysts 下载免费PDF全文
Keisuke Obata Prof. Kazuhiro Takanabe 《Angewandte Chemie (International ed. in English)》2018,57(6):1616-1620
Highly active NiFeOx electrocatalysts for the oxygen evolution reaction (OER) suffer gradual deactivation with time owing to the loss of Fe species from the active sites into solution during catalysis. The anodic deposition of a CeOx layer prevents the loss of such Fe species from the OER catalysts, achieving a highly stable performance. The CeOx layer does not affect the OER activity of the catalyst underneath but exhibits unique permselectivity, allowing the permeation of OH? and O2 through while preventing the diffusion of redox ions through the layer to function as a selective O2‐evolving electrode. The use of such a permselective protective layer provides a new strategy for improving the durability of electrocatalysts. 相似文献
46.
Pd(II)-SPRIX catalyst coupled with an environmentally benign molecular oxygen as the sole oxidant successfully exploited the construction of pyrrolizines/pyrroloindoles, imperative scaffolds of bio-potent molecules through intramolecular C-N and C-C bond forming reactions in good yields with appreciable enantioselectivities. 相似文献
47.
Silicon substrate surface and silica particle surface were modified with five kinds of polymers, poly(2-methoxyethyl methacrylate) (pMEMA), poly(2-hydroxyethyl methacrylate) (pHEMA), poly(acrylamide) (pAAm), poly(methyl methacrylate) (pMMA), and poly(styrene) (pSt), using a combined polymerization of surface-initiated polymerization that gives dense polymer chain layers and atom transfer radical polymerization (ATRP) that yields polymers with a narrow molecular weight distribution. Measurements of water contact angle and polymer chain amount on the modified silicon substrate surface and adsorption amounts of proteins (albumin and fibrinogen) on the modified silica particle surface revealed that the amount of polymer on the modified surface greatly affects the suppression of protein adsorption on the surface. 相似文献
48.
49.
Kondo M Miyazawa M Irie Y Shinagawa R Horiba T Nakamura A Naito T Maeda K Utsuno S Uchida F 《Chemical communications (Cambridge, England)》2002,(18):2156-2157
A coordination polymer [Zn(pyta)(OH)] (pyta = 4-pyridylthioacetate), was synthesized and structurally characterized; it is constructed by an alternating assembly of two types of homo-chiral helices, [Zn-OH] and [Zn-pyta], in which the sulfide moieties are fastened in the latter columns. 相似文献
50.
The reaction of 1-bromo-2-(1-isothiocyanatoalkyl)benzenes, which are easily derived from 2-bromophenyl ketones or (2-bromophenyl)methanamine, with butyllithium generates 1-(1-isothiocyanatoalkyl)-2-lithiobenzenes, which immediately underwent intramolecular cyclization to give rise to the corresponding 3-substituted and 3,3-disubstituted 2,3-dihydro-1H-isoindole-1-thiones in good yields. 相似文献