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991.
甲状腺素脱碘酶是一种膜硒蛋白[1], 它能够将甲状腺素降解为不同产物, 并对甲状腺素的生理功能起调控作用. 但是, 甲状腺素脱碘酶极易变性失活, 到目前为止仍未得到纯酶[2]. 近来, 此酶的人工模拟工作逐渐成为热点. 我们小组[3]首次以3,5,3′,5′-四碘甲状腺原氨酸五水钠盐(T4)为半抗原, 采用单克隆抗体技术和苯甲基磺酰氟及硒氢化钠修饰的方法, 成功地制备了具有甲状腺素脱碘酶活性的抗体酶. 相似文献
992.
Marcelo P. de Oliveira 《Geometriae Dedicata》2001,86(1-3):227-247
In this paper we present some expressions for the canonical kernel function of a bounded symmetric domain. We show how it is related both to the reproducing kernel of a holomorphic discrete series representation and to the contravariant form on highest weight modules over semisimple Lie algebras of Hermitian type. 相似文献
993.
61. IntroductionLet G be a trite grouP and S a subs6t of G such thst 1' S and S = S--1. The Cayleygraph X = Cay(G, S) Of G with respect to S is defined to have vertex set V(X) = G and edgeset E(X) = {(g, ag) I g E G, s E' S}. ~ the defection the following two faCts are obvious:(1) the automorphism group Ant(X) of X contains GR, the right regular representation ofG, as a subgroup, and (2) X is cormected if and only if S generates the group G.FOr a Cayley graph X = Cay(G, S) Of … 相似文献
994.
谈谈与图有关的几种复形的同调群 总被引:2,自引:0,他引:2
我们从组合拓扑方法在图论的应用中,着重介绍与图有关的几种复形的近期研究动态,论述其中一些基础性的问题,并提出一些可供研究的新问题。 相似文献
995.
Eight new homologous series of 4-alkyl-N-(4-alkloxysalicylidene)anilines were synthesized. The phase transitions of these homologues were determined using differential scanning calorimetry and polarizing optical microscopy. The homologues began to exhibit liquid crystalline phases as the terminal alkyl or alkoxyl chains were lengthened. In addition, some members of these homologues series exhibited photochromism in the solid state. 相似文献
996.
An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid was discovered in a diazo-coupling process.The reaction occurred under mild reaction conditions (pH 8.0-9.0.0-5 C,solvent:water) within a short reaction time(1h).A plausible substitution reaction mechanism by phenol-ketone resonance was proposed. 相似文献
997.
Alexander Ryabchun Alexey Bobrovsky Sung‐Ho Chun Valery Shibaev 《Journal of polymer science. Part A, Polymer chemistry》2013,51(19):4031-4041
A new approach to the synthesis of photoactive comb‐shaped homo‐ and copolyamides containing azobenzene, cinnamate, and coumarin side groups for photoalignment of liquid crystals was elaborated. Photooptical properties and photoorientational ability of these polymers with respect to liquid crystals were studied. It was shown that polarized UV irradiation of all spin‐coated polyamides leads to orientation of liquid crystalline molecules deposited on the polyamide thin films. The synthesized polymers containing cinnamate and coumarin side groups as well as azobenzene‐containing cyano‐ and nitro‐substituted polymers demonstrated good orientation ability in relation to liquid crystals displaying photoinduced planar orientation with high dichroism values within the range of 0.68–0.72. Contrary to the above‐mentioned polyamides, azobenzene‐containing fluorosubstituted polymers induced a homeotropic orientation of liquid crystals. It was shown that the synthesized photoactive polyamides can be considered as promising photoalignment materials for application in display technology, photonics, and other “smart” optical devices. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4031–4041 相似文献
998.
Tetsushi Kijima Masakazu Nishida Haruhiko Fukaya Masato Yoshida Hideo Sawada 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2555-2564
A reddish‐brown fluoroalkyl end‐capped 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) oligomer/acetone composite was prepared by heating the white oligomer powder with acetone at 80 °C for 3 h. The color was not observed in the corresponding non‐fluorinated AMPS oligomer/acetone composite, which was prepared under similar conditions. The coloring was probably caused by the formation of acetone polyaldol condensation products in the fluorinated oligomeric gel network cores. The colored RF‐(AMPS)n‐RF/acetone composite powders were stable and did not exhibit any color change after 2 years in natural light at room temperature. The colored composite powders dissolved in methanol to give a reddish‐brown solution at room temperature. However, the retro‐polyaldol condensation decolored the solution after 1 day at room temperature. This is the first example of the retro‐aldol polycondensation of acetone under mild conditions. The decoloration increased by between 38‐ and 70‐fold under UV irradiation, compared with that in dark conditions. The coloring–decoloring behavior was consistent and repeatable; therefore our fluorinated oligomer/acetone composites are promising candidates for new fluorinated coloring materials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2555–2564 相似文献
999.
Hongmei Qin Lisheng Li Tianxiang Liang Xiaobin Peng Junbiao Peng Yong Cao 《Journal of polymer science. Part A, Polymer chemistry》2013,51(7):1565-1572
Four new donor–acceptor (donor) [D–A(D)], PBDT‐PTQ, PBDT‐PTTQ, PBDT‐TQ, and PBDT‐TTQ, bearing the same backbone of alternative benzodithiophene (BDT) and quinoxaline units but with phenylene thienyl, phenylene di‐thienyl, thienyl and di‐thienyl groups (other donors), respectively, at the acceptor quinoxaline units, were designed and synthesized to investigate the impacts of the conjugated side chains at the acceptor units on the photovoltaic properties of polymers. The power conversion efficiencies (PCEs) of the polymer solar cells (PSCs) based on PBDT‐TQ:[6,6]‐phenyl‐C‐70‐butyric acid methyl ester (PC70BM) and PBDT‐PTQ:PC70BM reach to 4.39 and 3.58%, respectively, which are 43 and 17% higher, respectively, than that of a reported alkylphenyl substituted polymer with the same main chain. However, the PCEs based on PBDT‐TTQ and PBDT‐PTTQ, in which an additional thiophene is added at a side chain of PBDT‐TQ and PBDT‐PTQ, respectively, decline. The mechanism how the conjugated side chains affect the performance of the PSCs is also discussed. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
1000.
Inmaculada Robina Silvia Gómez-Bujedo José G. Fernández-Bolaños José Fuentes 《合成通讯》2013,43(13):2379-2397
To prepare C-sulfonate derivatives of disaccharides two different strategies were followed. Thus 6- and 6′-C-sulfocellobiosides 4 and 10–12 were prepared starting from a suitably protected cellobioside. The 6′-C-sulfoaminocellobioside 18 was prepared by construction of the molecule through a glycosylation reaction. In both cases, the synthetic pathway involves regioselective tosylation, introduction of a sulfur atom by nucleophilic displacement with potassium thioacetate and oxidation with hydrogen peroxide. 相似文献