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991.
合成了标题化合物{Mn(IBG)(4,4'-bipy)(H2O)2}·(H2O)2(H2IBG =1,3-苯二甲酰二甘氨酸,4,4'-bipy=4,4'-联吡啶),并通过X-射线衍射对其单晶结构进行了测定.该结构属于三斜晶系,空间群P-1,分子量Mr=561.41,晶胞参数a=0.90278(8)nm,b=1.16584(1)nm,c=1.31133(1)nm,V=1.21309(2)nm3,Z=2,Dc=1.537g·cm-3,F(000)=582.0.由于分子间氢键,使得分子结构更趋稳定.通过红外光谱、热重分析等对化合物进行了表征. 相似文献
992.
Yong-Hong Zhang Masao Nomura Yasuhiko Fujii Takao Oi 《Isotopes in environmental and health studies》2013,49(3):279-288
Isotope effects of cerium were observed in malate and lactate complex formations during the long-distance displacement chromatographic processes at 313 K. Heavier isotopes were found fractionated in the frontal edges of the Ce adsorption bands in both the systems, registering a preference of the heavier isotopes for the Ce(III) complexes in the solution phase over the simply hydrated Ce(III) ions in the resin phase. The fractionation coefficients ? for the 136Ce/140Ce, 138Ce/140Ce and 142Ce/140Ce isotopic pairs were 7.1 × 10?6, 5.2 × 10?6 and ?2.1 × 10?6 for the malate system, and 4.8 × 10?6, 4.5 × 10?6 and?2.6×10?6 for the lactate system, respectively. They all show the mass-dependent law if the deviation of ? for the 138Ce/140Ce pair was considered merely due to the isobaric interference in Ce isotopic ratio measurements, suggesting the molecular vibration, rather than the nuclear field shift, mainly contributes to the Ce isotope effects in the complex formation systems. The absolute values of ? between the two systems are comparable, suggesting no instinct difference in structural properties between Ce malate and lactate complexes involved. 相似文献
993.
We consider an infinite Hermitian positive definite matrix M which is the moment matrix associated with a measure μ with infinite and compact support on the complex plane. We prove that if the polynomials are dense in L2(μ) then the smallest eigenvalue λn of the truncated matrix Mn of M of size (n+1)×(n+1) tends to zero when n tends to infinity. In the case of measures in the closed unit disk we obtain some related results. 相似文献
994.
S. Jung 《Journal of Mathematical Analysis and Applications》2011,379(1):325-260
In this paper we study properties of complex symmetric operators. In particular, we prove that every complex symmetric operator having property (β) or (δ) is decomposable. Moreover, we show that complex symmetric operator T has Dunford?s property (C) and it satisfies Weyl?s theorem if and only if its adjoint does. 相似文献
995.
Laura Hitt O'Connor Gary McGuire Michael Naehrig Marco Streng 《Journal of Number Theory》2011,131(5):920-935
We construct Weil numbers corresponding to genus-2 curves with p-rank 1 over the finite field Fp2 of p2 elements. The corresponding curves can be constructed using explicit CM constructions. In one of our algorithms, the group of Fp2-valued points of the Jacobian has prime order, while another allows for a prescribed embedding degree with respect to a subgroup of prescribed order. The curves are defined over Fp2 out of necessity: we show that curves of p-rank 1 over Fp for large p cannot be efficiently constructed using explicit CM constructions. 相似文献
996.
We give a new method for generating genus 2 curves over a finite field with a given number of points on the Jacobian of the curve. We define two new invariants for genus 2 curves as values of modular functions on the Hilbert moduli space and show how to compute them. We relate them to the usual three Igusa invariants on the Siegel moduli space and give an algorithm to construct curves using these new invariants. Our approach simplifies the complex analytic method for computing genus 2 curves for cryptography and reduces the amount of computation required. 相似文献
997.
A 2-D separation platform was constructed using micro strong cation-exchange liquid chromatography (μ-SCXLC) and reversed-phase pressurized capillary electrochromatography (RP-pCEC) for the analysis of complex samples. Samples were fractionated by the first-dimension μ-SCXLC with a linear solvent gradient and then injected into the second-dimension RP-pCEC for further separation. The μ-SCXLC/RP-pCEC 2-D system with three separation mechanisms, namely strong cation-exchange, reversed-phase chromatography and electrophoresis, provided high selectivity, high resolution and high peak capacity compared to one-dimensional chromatographic approaches. Separation effectiveness of this 2-D system was demonstrated by the analysis of different kinds of complex samples, such as traditional Chinese medicine Cortex Phellodendri, bovine serum albumin (BSA) tryptic digest and real serum tryptic digest. A theoretical peak capacity of approximately 1200 was achieved, which proves its promising potential for the separation and analysis of complex samples. 相似文献
998.
In this paper, we develop methods for establishing improved bounds on the moduli of the zeros of complex and real polynomials. Specific (lacunary) as well as arbitrary polynomials are considered. The methods are applied to specific polynomials by way of example. Finally, we evaluate the quality of some bounds numerically. 相似文献
999.
Miguel Romance 《Journal of Computational and Applied Mathematics》2011,235(7):1868-1874
We will analyze several centrality measures by giving a general framework that includes the Bonacich centrality, PageRank centrality or in-degree vector, among others. We will get some local scale estimators for such global measures by giving some geometrical characterizations and some deviation results that help to quantify the error of approximating a spectral centrality by a local estimator. 相似文献
1000.