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51.
S. V. Baires D. É Vallen K. M. Enikeev A. S. Khramov V. E. Bel'skii A. V. Il'yasov B. E. Ivanov 《Russian Chemical Bulletin》1992,41(10):1801-1804
The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2301–2305, October, 1992. 相似文献
52.
Jingjing Xu Yidong Lu Baohong Liu Chunhe Xu Jilie Kong 《Journal of Solid State Electrochemistry》2007,11(12):1689-1695
An ultrathin, ordered, and packed protein film, consisting of the 2-mercaptoacetic acid (MAA), polydimethyldiallylammonium
chloride (PDDA), and wild-type (WT) photosynthetic reaction center (RC; termed as WT-RC) or its pheophytin (Phe)-replaced
counterpart (termed as Phe-RC), was fabricated by self-assembling technique onto gold electrode for facilitating the electron
transfer (ET) between RC and the electrode surface. Near-infrared (NIR)-visible (Vis) absorption and fluorescence (FL) emission
spectra revealed the influence of pigment substitution on the cofactors arrangement and excitation relaxation of the proteins,
respectively. Square wave voltammetry (SWV) and photoelectric tests were employed to systematically address the differences
between the WT-RC films and mutant ones on the direct and photo-induced ET. The electrochemical results demonstrated that
ET initiated by the oxidation of the primary donor (P) was obviously slowed down, and the formed P+ had more population as well as more positive redox potential in the Phe-RC films compared with those in the WT ones. The
photoelectrochemical results displayed the dramatically enhanced photoelectric performances of the mutant ones, further suggesting
the slow-down formation of final charge-separated state in Phe-RC. The functionalized protein films introduced in this paper
provided an efficient approach to sensitively probe the redox cofactors and ET differences resulting from only minor changes
in pigment arrangement in the pigment–protein complex. The favored ET process observed for the membrane proteins RC was potentially
valuable for a deep understanding of the multi-step biological ET process and development of versatile bioelectronic devices. 相似文献
53.
L. I. Komarova Ts. M. Frenkel' A. E. Shvorak V. A. Pankratov B. N. Lokshin 《Russian Chemical Bulletin》1996,45(7):1572-1578
The structure of the dimethylbenzylamine (DMBA)—phenylglyc idyl ether (PGE)—phenol complex was studied by IR and1H NMR spectroscopy under various conditions of its formation. The active catalyst in the cyclotrimerization of isocyanates is a complex of composition DMBA : PGE : PhOH = 1 : 1 : 2, in which the oxygen atom of the zwitter-ion PhCH2N+Me2CH2CH(O–)CH2OPh that forms after opening, of the epoxide cycle is bound to two phenol molecules by a very strong hydrogen bonds. In this complex, the oxygen atom of both the zwitter-ion and the phenolate anion can be catalytic centers. Two schemes of the cyclotrimerization of isocyanate in the presence of the aforementioned catalytic system are suggested, depending on whether the catalytic complex has time to form or not.For Part I, see Ref. 1.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1662–1668, July, 1996. 相似文献
54.
Jan Budziski 《International journal of quantum chemistry》2004,97(4):832-843
An algorithm for evaluation of two‐center, three‐electron integrals with the correlation factors of the type rr and rrr as well as four‐electron integrals with the correlation factors rrr and rrr in the Slater basis is presented. This problem has been solved here in elliptical coordinates, using the generalized and modified form of the Neumann expansion of the interelectronic distance function r for k ≥ ?1. Some numerical results are also included. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
55.
The palladium-catalyzed regio- and diastereo-selective allylic alkylation of allyl acetates with carbon nucleophiles occurred. The stereochemistry was highly controlled by the palladium catalyst with 2-(diphenylphosphino)benzoic acid as the ligand, and vicinal quaternary and tertiary carbon centers were constructed. 相似文献
56.
X射线辐照前后,在BaF(Cl,Br):Sm^2+中以560nm的Nd:YAG脉冲光在液氮温度下进行了双光子烧孔实验和光激励发光实验,结果表明,Sm^2+掺杂的碱土金属氟卤化物光谱烧孔过程中伴随着光激励发光过程,这一过程直接影响光谱烧孔过程的进行。 相似文献
57.
本文通过对TiCl_3-Al(C_2H_5)_3聚合1-辛烯产物的双峰型分子量分布曲线用Schulz函数进行拟合、分峰处理,发现这种双峰型分布中的高分子量峰部分由一种活性中心生成,低分子量峰部分则由至少两种活性中心生成.将不同转化率时聚辛烯的分子量分布分峰拟合数据与聚合速率、活性中心数等测定数据相结合,得到了高分子量和低分子量两部分产物相应的活性中心上各自的动力学参数(增长速率常数、活性中心数、链转移常数等)及各自的聚合速率曲线,从而证实了多种活性中心的存在、它们催化特性的差异及与聚合物分子量分布增宽的关系. 相似文献
58.
Single crystals of [CuCl0.85Br0.15(C6H4N3CH2=CH2)] (I) were obtained by alternating current electrochemical synthesis; their X-ray structural investigation has been carried
out (DARCh automatic diffractometer, MoK
α radiation, θ/2θ scanning; 1460 reflections with F ≥ 4σ(F), R = 0.0517). The crystals are monoclinic, their space group is P21/c, a = 7.292(3) Å, b = 17.947(8) Å, c = 7.398(4) Å, β = 93.56(4)°, V = 966(1) Å3, Z = 4). Complex I is close in structure to the previously investigated compound [CuCl(C6H4N3CH2=CH2)] (II). In both structures, the trigonal-pyramidal surroundings of the copper atom include two halide atoms (one is apical),
a nitrogen atom, and a C=C group. The Cu2X2 dimers are associated into {[Cu2X2(C6H5N3CH2=CH2)]}n layers due to the bridging function of the 1-allylbenzotriazole molecule. In spite of the similar coordination polyhedra
of the metal atoms and identical bridging function of the ligand molecule in I and II, the differences in the conformation
parameters of the allyl group π-coordinated by the copper(I) atom (trans-like in I and cis-like in II) caused by the presence
of bromine atoms in the coordination sphere predetermine different structures of the organometallic [Cu2X2(C6H5N3CH2=CH2)]4 tetramer subunits in the layers and, as a consequence, formation of different crystal structures.
Original Russian Text Copyright ? 2005 by E. A. Goreshnik, B. M. Mykhalichko, and V. N. Davydov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 1, pp. 174–178, January–February, 2005. 相似文献
59.
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