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91.
高纯度烟草过氧化物酶(TOP I)光谱特性研究 总被引:1,自引:0,他引:1
采用交换吸附脱色及柱层析新技术,成功地从烟叶中分离和纯化了一种烟草过氧化物酶同工酶(TOP I),并对其进行了一系列光谱特性研究。基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)测得TOP I分子量为21888.5,等电点pI为3.5;氨基酸组成分析表明TOP I为一含血红素的酸性蛋白酶。光谱学分析揭示,在402nm处有一典型的Soret带,在498和636nm处有特征吸收峰(α,β带),酸度和变性剂对TOP I在紫外可见区的特征吸收峰均产生一定的影响,TOP I的荧光光谱测定结果说明TOP I分子中含有Trp残基和Tyr残基以及其自身的独特的光谱学特性。 相似文献
92.
Elke Baum Patrik Dahlke Volker Kaiser Michel Molinier Roland E. Schmidt Jürgen Pebler Werner Massa Dietrich Babel 《无机化学与普通化学杂志》2006,632(14):2244-2250
93.
用Raman和IR光谱研究乙酰胺和Ag(Ⅰ)-C(Ⅱ)离子的作用。结果发现,Ag(Ⅰ)和Cu(Ⅱ)离子可增强对乙酰胺光谱频带的识别能力,原在AA中被掩盖的某些谱带,由于Ag-Cu离子的进入而得到了辨认。 相似文献
94.
The aim of this paper is to point out the equivalence between three notions respectively issued from recursion theory, computational complexity and finite model theory. One the one hand, the rudimentary languages are known to be characterized by the linear hierarchy. On the other hand, this complexity class can be proved to correspond to monadic second-order logic with addition. Our viewpoint sheds some new light on the close connection between these domains: We bring together the two extremal notions by providing a direct logical characterization of rudimentary languages and a representation result of second-order logic into these languages. We use natural arithmetical tools, and our proofs contain no ingredient from computational complexity. 相似文献
95.
96.
An induced matching of a graph G is a matching having no two edges joined by an edge. An efficient edge dominating set of G is an induced matching M such that every other edge of G is adjacent to some edge in M. We relate maximum induced matchings and efficient edge dominating sets, showing that efficient edge dominating sets are maximum induced matchings, and that maximum induced matchings on regular graphs with efficient edge dominating sets are efficient edge dominating sets. A necessary condition for the existence of efficient edge dominating sets in terms of spectra of graphs is established. We also prove that, for arbitrary fixed p≥3, deciding on the existence of efficient edge dominating sets on p-regular graphs is NP-complete. 相似文献
97.
Abbas Heydari 《Linear algebra and its applications》2008,429(7):1744-1757
Let H be a simple graph with n vertices and G be a sequence of n rooted graphs G1,G2,…,Gn. Godsil and McKay [C.D. Godsil, B.D. McKay, A new graph product and its spectrum, Bull. Austral. Math. Soc. 18 (1978) 21-28] defined the rooted product H(G), of H by G by identifying the root vertex of Gi with the ith vertex of H, and determined the characteristic polynomial of H(G). In this paper we prove a general result on the determinants of some special matrices and, as a corollary, determine the characteristic polynomials of adjacency and Laplacian matrices of H(G).Rojo and Soto [O. Rojo, R. Soto, The spectra of the adjacency matrix and Laplacian matrix for some balanced trees, Linear Algebra Appl. 403 (2005) 97-117] computed the characteristic polynomials and the spectrum of adjacency and Laplacian matrices of a class of balanced trees. As an application of our results, we obtain their conclusions by a simple method. 相似文献
98.
Preparation and Characterization of Iodoplatinates MexNH4–xPtI4 (x = 2–4), Mixed Valence Octaiododiplatinates(II,IV) with Pt2I8 Groups Iodoplatinates APtI4 (A = MexNH4–x with x = 2–4) have been prepared by partial oxidation of the correspondent hexaiododiplatinates(II) A2Pt2I6 with I2 in methanolic solutions. X-ray structure analyses of the bronze-coloured needle-shaped crystals of the compounds showed rows of dinuclear anions Pt2I82?, built up by edgesharing planar PtI4 groups with PtII und octahedral PtI6 groups with PtIV. The different space requirement of the cations leads to the formation of three different structures. Within the anion stacks weak intermolecular PtIV? I …? PtII interactions are detectable by Raman spectroscopy. 相似文献
99.
100.
使用四甲氧基硅烷(TMOS)和二甲基二甲氧基硅烷(DiMe-DMOS)为共先驱体,采用溶胶-凝胶的有机掺杂,制备对pH具有宽程响应的敏感膜。详细考察了包埋溴酚蓝和溴酚绿的敏感膜对pH的响应值、响应时间、泄漏和可逆性等响应性能指标,并进行了溴酚蓝和溴酚绿在水相与膜内吸收光谱的研究。 相似文献