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151.
Chuande Wu Xiang Lin Rongmin Yu Wenbin Yang Canzhong Lu Honghui Zhuang 《中国科学:化学(英文版)》2001,44(1):49-54
The reaction of an aqueous solution of sodium molybdate with iron powder at low pH (~0.184) gives rise to the formation of a six-member Mo ring-shape cluster with an Fe (II) encapsulated at the center, [Na4(H2O)7][Fe(OH)6Mo6O18](1), which is further linked to a remarkable three-dimensional network via sodium ions. 相似文献
152.
规模化蛋白质生物质谱鉴定中肽段氨基端环化修饰现象 总被引:1,自引:1,他引:0
对蛋白质样品制备中引入的氨基酸残基的一种现象--蛋白质酶切肽段氨基端的环化修饰现象的初步研究结果显示,很多以谷氨酰胺(Q)或氨乙酰化修饰的半胱氨酸(CAM_C)残基起始的肽段会发生氨基端的环化修饰,且修饰反应不完全,在同一样本中修饰与非修饰两种状态常同时存在,并且环化修饰后的肽段的反相色谱保留时间发生延迟.在数据库检索时添加环化修饰,可以提高蛋白质的鉴定成功率.本研究结果为大规模的蛋白质质谱数据解析提供了有价值的参考. 相似文献
153.
Yuanlin Ren Bowen Cheng Jinshu Zhang Weimin Kang Zhenhuan Li Xupin Zhuang 《Frontiers of Chemistry in China》2009,4(2):136-141
The thermal decomposition kinetics of the N,N′-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylenediamine (DPTDEDA) in air were studied by TGDTG techniques. The
kinetic parameters of the decomposition process for the title compound in the two main thermal decomposition steps were calculated
through the Friedman and Flynn-Wall-Ozawsa (FWO) methods and the thermal decomposition mechanism of DPTDEDA was also studied
with the Coats-Redfern and Achar methods. The results show that the activation energies for the two main thermal decomposition
steps are 128.03 and 92.59 kJ·mol−1 with the Friedman method, and 138.75 and 106.78 kJ·mol−1 with the FWO method, respectively. Although there are two main thermal decomposition steps for DPTDEDA in air, the thermal
decomposition mechanism of DPTDEDA in the two steps are the same, i.e. f(α) = 3/2(1 − α)4/3[(1 − α)−1/3 − 1]−1.
__________
Translated from Acta Chimica Sinica, 2008, 66(9) (in Chinese) 相似文献
154.
A conductive carbon paste electrode (CPE) comprising a new zinc complex of [Zn(C11H15N3)2Cl2] and carbon powder was fabricated by the direct mixing method. The structure of [Zn(C11H15N3)2Cl2] was characterized by X-ray crystallography and elemental analysis. The electrochemical behavior and electrocatalysis of
the new zinc complex modified CPE (Zn–CPE) have been studied in detail. This bulk-modified Zn–CPE displayed good electrocatalytic
activity toward the reduction of the hydrogen peroxide and nitrite. The results are reproducible with a lower detection limit
than reported currently using other modified electrodes. Also, this bulk-modified CPE exhibits remarkable long-term stability,
simple preparation, and inexpensive material, which is important for practical application on electrochemistry sensors. 相似文献
155.
Yong‐Qin Wei Ke‐Chen Wu Bo‐Tao Zhuang Zhang‐Feng Zhou Ming‐Xin Zhang Cai‐Ping Liu 《无机化学与普通化学杂志》2005,631(8):1532-1535
The silver complex Ag(PPh3)2(H2TMT) ( 1 )(H3TMT = 2,4,6‐trimercapto‐1,3,5‐triazine) has been synthesized and characterized. The ligand trimercaptotriazine exhibits a novel coordination mode and the complex shows a special hydrogen bonding linkage in the crystal packing. The colorless crystals of 1 exhibit broad emission in the visible region at room temperature. TDDFT calculation indicated that the π–π attraction is crucial for fluorescence of the title complex. 相似文献
156.
157.
Let C be a class of unital C*-algebras. The class TAC of C*-algebras which can be tracially approximated (in the Egorov-like sense first considered by Lin) by the C*-algebras in C is studied (Lin considered the case that C consists of finite-dimensional C*-algebras or the tensor products of such with C([0,1])). In particular, the question is considered whether, for any simple separable A∈TAC, there is a C*-algebra B which is a simple inductive limit of certain basic homogeneous C*-algebras together with C*-algebras in C, such that the Elliott invariant of A is isomorphic to the Elliott invariant of B. An interesting case of this question is answered. In the final part of the paper, the question is also considered which properties of C*-algebras are inherited by tracial approximation. (Results of this kind are obtained which are used in the proof of the main theorem of the paper, and also in the proof of the classification theorem of the second author given in [Z. Niu, A classification of tracially approximately splitting tree algebra, in preparation] and [Z. Niu, A classification of certain tracially approximately subhomogeneous C*-algebras, PhD thesis, University of Toronto, 2005]—which also uses the main result of the present paper.) 相似文献
158.
159.
160.
Xuan Pang Xuesi Chen Xiuli Zhuang Xiabin Jing 《Journal of polymer science. Part A, Polymer chemistry》2008,46(2):643-649
Enolic Schiff base zinc (II) complex 1 was synthesized. XRD revealed 1 was a novel crown‐like macrocycle structure consisted of hexanuclear units of (LZnEt)6 via the coordination chelation between the Zn atom and adjacent amine nitrogen atom. Further reaction of 1 with one equivalent 2‐propanol at RT produced Zn‐alkoxide 2 by in situ alcoholysis. Complex 2 was used as an initiator to polymerize rac‐lactide in a controlled manner to give heterotactic enriched polylactide. Factors that influenced the polymerization such as the polymerization time and the temperature as well as the monomer concentration were discussed in detail in this paper. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 643–649, 2008 相似文献