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41.
《Electroanalysis》2002,14(23):1648-1653
An electrochemical equation suitable for examining the interaction of irreversible redox compounds with DNA is established. According to the equation, diffusion coefficients of both free and binding compounds (Df , Db), binding constant (K) and binding site size (s) of compounds with DNA could be obtained simultaneously by nonlinear fit analysis of electrochemical data. Bis‐benzimidazole derivative (Hoechst 33258), as an irreversible redox compound, was investigated for its electrochemical behavior and the interaction with natural fish sperm DNA (fsDNA) using cyclic voltammetry, chronocoulometry, bulk electrolysis and scanning electrochemical microscope technique. A nonlinear fit analysis of the experimental data yielded: Df=8.3×10?5 cm2 s?1, Db=6.0×10?6 cm2 s?1, K=2.1×108 cm3 mol?1, s=3.9. The overall results suggest that Hoechst 33258 binds tightly to the minor groove of fsDNA and covers four base pairs. 相似文献
42.
在对未成年被告人判决宣告前,由专门机构或专门人员对未成年被告人犯罪行为的背景情况进行社会调查,并对其人身危险性和再犯可能性进行专业系统分析,以供法院参考,使判处的刑罚有利于未成年罪犯的改过自新及健康成长。从调查人员、调查机构、调查内容、调查程序和调查方式等各方面建构,完善未成年被告人判前社会调查制度,并应用于司法实践,努力实现对未成年罪犯的挽救教育和再社会化。 相似文献
43.
We report on an optical aptamer sensor for cocaine detection. The cocaine sensitive fluorescein isothiocyanate (FITC)-labeled aptamer underwent a conformational change from a partial single-stranded DNA with a short hairpin to a double-stranded T-junction in the presence of the target. The DNA minor groove binder Hoechst 33342 selectively bound to the double-stranded T-junction, bringing the dye within the Förster radius of FITC, and therefore initiating minor groove binder based energy transfer (MBET), and reporting on the presence of cocaine. The sensor showed a detection limit of 0.2 μM. The sensor was also implemented on a carboxy-functionalized polydimethylsiloxane (PDMS) surface by covalently immobilizing DNA aptamers. The ability of surface-bound cocaine detection is crucial for the development of microfluidic sensors. 相似文献
44.
Masao Ishikawa 《The Ramanujan Journal》2008,16(2):211-234
In the open problem session of the FPSAC’03, R.P. Stanley gave an open problem about a certain sum of the Schur functions.
The purpose of this paper is to give a proof of this open problem. The proof consists of three steps. At the first step we
express the sum by a Pfaffian as an application of our minor summation formula (Ishikawa and Wakayama in Linear Multilinear
Algebra 39:285–305, 1995). In the second step we prove a Pfaffian analogue of a Cauchy type identity which generalizes Sundquist’s
Pfaffian identities (J. Algebr. Comb. 5:135–148, 1996). Then we give a proof of Stanley’s open problem in Sect. 4. At the end of this paper we present certain corollaries obtained
from this identity involving the Big Schur functions and some polynomials arising from the Macdonald polynomials, which generalize
Stanley’s open problem.
相似文献
45.
In a previous paper (J. Combin. Theory 48 (1990) 255) we showed that for any infinite set of (finite) graphs drawn in a fixed surface, one of the graphs is isomorphic to a minor of another. In this paper we extend that result in two ways:
- • we generalize from graphs to hypergraphs drawn in a fixed surface, in which each edge has two or three ends, and
- • the edges of our hypergraphs are labelled from a well-quasi-order, and the minor relation is required to respect this order.
46.
A unique factorization theorem for matroids 总被引:2,自引:0,他引:2
We study the combinatorial, algebraic and geometric properties of the free product operation on matroids. After giving cryptomorphic definitions of free product in terms of independent sets, bases, circuits, closure, flats and rank function, we show that free product, which is a noncommutative operation, is associative and respects matroid duality. The free product of matroids M and N is maximal with respect to the weak order among matroids having M as a submatroid, with complementary contraction equal to N. Any minor of the free product of M and N is a free product of a repeated truncation of the corresponding minor of M with a repeated Higgs lift of the corresponding minor of N. We characterize, in terms of their cyclic flats, matroids that are irreducible with respect to free product, and prove that the factorization of a matroid into a free product of irreducibles is unique up to isomorphism. We use these results to determine, for K a field of characteristic zero, the structure of the minor coalgebra of a family of matroids that is closed under formation of minors and free products: namely, is cofree, cogenerated by the set of irreducible matroids belonging to . 相似文献
47.
48.
采用熔融玻璃片制样,选用标准样品,以经验α系数和散射线内标法校正元素谱线重叠干扰和基体效应,使用ZSX Primus Ⅱ X射线荧光光谱仪对黏土样品中的Al2O3、SiO2、Fe2O3、CaO、MgO、K2O、Na2O、MnO、P2O5、TiO2、Cu、Cr等组分进行测定,分析结果与标准值和化学值相吻合,12次测定的相对标准偏差小于10%. 相似文献
49.
Catharina Nästren Regis Jardin Marcus Walter Boris Brendebach 《Journal of solid state chemistry》2009,182(1):1-9463
Actinides (thorium, uranium, neptunium, plutonium, and americium) were infiltrated into a porous Nd1.8Zr2O6.7 matrix, prepared by gel-supported precipitation. (Nd1.8An0.2)Zr2O7+x pyrochlores were formed after sintering in Ar/H2 and the pyrochlore structure remains during oxidation at 800 °C in air. X-ray diffraction reveals a linear relationship between the pyrochlore lattice parameter and the ionic radii of the actinides. EXAFS measurements on actinide L3-edge show a split shell of nearest neighbour oxygen atoms similar to that surrounding of Nd. The actinide-oxygen bond distances decrease with the actinide ionic radii, which verifies that these actinides adopt the Nd site in the (Nd1.8An0.2)Zr2O7+x pyrochlore. The oxidation susceptibility of Np is related to the availability of oxygen vacancies and in contrast to stabilised zirconia Np(V) can be obtained in zirconia based pyrochlore. 相似文献
50.
给出了树宽≤2的图也就是系列并行图的几个等价刻画。证明了对有限图G(可以有环有重边)以下四断言彼此等价:(1)G是系列并行图,(2)G的任一个minor至少有一个点的度≤2;(3)G不以4阶完全图为minor;(4)G无子图同胚于4阶完全图。 相似文献