摘要：
A novel carbazole functionalized bis-β-diketone type organic ligand, 1,1′-(2,6-bispyridyl)bis-3-(9-ethylcarbazole-3-yl)-1,3-propanedione (H2L) and its corresponding lanthanide complexes Eu2(L)3and Tb2(L)3 were successfully prepared. The ligand and complexes were characterized in detail based on FT-IR spectra, 1H NMR and elemental analysis. The observed UV-Vis absorption and photoluminescence properties of the complexes were investigated, it shows that the Eu(III) and Tb(III) ions can be sensitized efficiently by the ligand (H2L) to some extent, in particular, the complex Tb2(L)3 exhibits a more excellent luminescence property than the Eu(III) complex. Meanwhile, the introduction of the carbazole moiety can enlarge the π-conjugated system of the ligand and enhance the luminescent intensity of the complexes. The results show that the complexes would be used as excellent luminescent materials.
摘要：
The modified Schultz index of a graph is defined as S*(G) = Σ{u, v}⊂V(G)(d(u)·d(v))dG(u, v) where d(u) (or d(v)) is the degree of the vertex u (or v), and dG(u, v) is the distance between u and v. Explicit formulas for calculating the modified Schultz index of Zig-zag polyhex nanotubes are provided in this paper.
摘要：
For a graph G = (V, E), the modified Schultz index of G is defined as S*(G) = Σ{u, v}⊂V(G) (d(u)·d(v))dG(u, v) where d(u) (or d(v)) is the degree of the vertex u (or v) of G, and dG(u, v) is the distance between u and v. Explicit formulas for calculating the modified Schultz index of armchair polyhex nanotubes are provided in this paper.
摘要：
In this paper, we deal with a class of inequality problems for dynamic frictional contact between a piezoelectric body and a foundation. The model consists of a system of the hemivariational inequality of hyperbolic type for the displacement, the time dependent elliptic equation for the electric potential. The friction condition is described to be the Clarke subdifferential relations of nonmonotone and multivalued character in the tangential directions on the boundary. The existence of a weak solution to the model is proved by embedding the problem into a class of second-order evolution inclusions, and by applying a surjectivity result for multivalued operators.
期刊：
African Journal of Biotechnology,2009年8(23):6634-6637 ISSN：1684-5315
通讯作者：
Jing, Longjun
作者机构：
[Zhou, Zhengwei] Hunan City Univ, Yiyang 413000, Hunan, Peoples R China.;[Feng, Qiang; Jing, Longjun; Xiao, Yuanshi] Qujing Normal Univ, Qujing 655011, Yunnan, Peoples R China.;[Cui, Guowen] Yuxi Normal Univ, Yuxi 653100, Yunnan, Peoples R China.
通讯机构：
[Jing, Longjun] Q;Qujing Normal Univ, Qujing 655011, Yunnan, Peoples R China.
关键词：
A study was undertaken to evaluate the effects of polysaccharide from Lycium barbarum (LBP) in alloxan-induced diabetic mice. The various parameters studied included body weight;fasting blood glucose levels;total cholesterol (TC) andtriglyceride (TG) in diabetic and normal mice. LBP treatment (20;40 mg/ kg body weight) for 28 days resulted in a significant decrease in the concentration of fasting blood glucose (FBG);total cholesterol (TC) and triglyceride (TG) in diabetes mellitus mice. Furthermore;LBP significantly increased body weight (bw). The data demonstrated LBP at the dose of 40 mg/kg bw exhibited the optimal effect.
关键词：
Bose-Einstein condensation;Gravitational field;Finite number effects
摘要：
Microscopic bouncing balls, i.e., particles confined within a positive one-half-dimensional gravitational potential, display Bose-Einstein condensation (BEC) not only in the thermodynamic limit but also in the case of a finite number of particles, and the critical temperature with a finite number of particles is higher than that in the thermodynamic limit. This system is different from the one-dimensional harmonic potential one, for which the standard result indicates that the BEC is not possible unless the number of particles is finite. (c) 2009 Elsevier B.V. All rights reserved.
作者：
Li Wen-bin;Pan Qing-lin*;Liu Jun-sheng;Liang Wen-jie;He Yun-bin;...
期刊：
中南大学学报(英文版),2009年16(4):530-534 ISSN：2095-2899
通讯作者：
Pan Qing-lin
作者机构：
[Liu Jun-sheng; Pan Qing-lin; Liang Wen-jie; Li Wen-bin; Liu Xiao-yan; He Yun-bin] Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China.;[Li Wen-bin] Hunan City Univ, Dept Civil Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Pan Qing-lin] C;Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China.
关键词：
Al-Zn-Cu-Mg-Sc-Zr alloy;hot deformation;flow softening;microstructural evolution;activation energy
摘要：
The deformation behavior of a new Al-Zn-Cu-Mg-Sc-Zr alloy was investigated with compression tests in temperature range of 380–470 °C and strain rate range of 0.001–10 s−1 using Gleeble 1500 system, and the associated microstructural evolutions were studied by metallographic microscopy and transmission electron microscopy. The results show that true stress—strain curves exhibit a peak stress, followed by a dynamic flow softening at low strains (ɛ<0.05). The stress decreases with increasing deformation temperature and decreasing strain rate, which can be represented by a Zener-Hollomon exponential equation with the activation energy for deformation of 157.9 kJ/mol. The substructure in the deformed specimens consists of few fine precipitates with equaixed polygonized subgrains in the elongated grains and developed serrations at the grain boundaries. The dynamic flow softening is attributed mainly to dynamic recovery and dynamic recrystallization.
期刊：
Journal of Computational and Theoretical Nanoscience,2009年6(3):662-666 ISSN：1546-1955
通讯作者：
Chen, Shubo
作者机构：
[Xiao, Zhengming] Hunan Univ Technol, Zhuzhou 412008, Hunan, Peoples R China.;[Li, Junfeng; Chen, Shubo] Hunan City Univ, Dept Math & Comp Sci, Yiyang 413000, Hunan, Peoples R China.
通讯机构：
[Chen, Shubo] H;Hunan City Univ, Dept Math & Comp Sci, Yiyang 413000, Hunan, Peoples R China.
关键词：
Distance;Modified Schultz index;Nanotube;Schultz index
摘要：
The modified Schultz index of a graph G is defined as S*(G) = Σ{u, v⊂V(G)(d(u)·d(v))dG(u, v) where d(u) (or d(v)) is the degree of the vertex u (or v), and dG (u, v) is the distance between u and v. Explicit formulas for calculating the modified Schultz index of nanotubes covered by C4 are provided in this report.
摘要：
Learning-based image steganalysis is an effective and universal approach to cope with the following two difficulties: unknown statistics and steganographic algorithms. A crucial part of the learning-based process is the selection of low-dimensional features, which strongly impacts the accuracy of classification. A novel principal feature selection and fusion (PFSF) method is presented to reduce features, and then it is applied to image steganalysis. First, we analyze the multicollinearity among features to eliminate redundant features. Next, we implement the linear transform based on principal components analysis (PCA) and use Savage decision-making to eliminate insignificant features. Last, in order to further reduce features, we fuse the selected features, followed by selecting the principal features from the fused features to form a new feature set. The advantage of the proposed method is that it needs the cover images only, without requiring the availability of the stego-images in the process of the features selection. Moreover, the proposed method greatly reduces the computational time. Our method has been tested on two feature sets from Moulin's and Fridrich's features. The experimental results show that our method not only reduces the feature number by 90%, but also provides more reliable detection results than the previous steganalysis methods do.
摘要：
Cry5Ba is a delta-endotoxin produced by Bacillus thuringiensis PS86A1 NRRL B-18900. It is active against nematodes and has great potential for nematode control. Here, we predict the first theoretical model of the three-dimensional (3D) structure of a Cry5Ba toxin by homology modeling on the structure of the Cry1Aa toxin, which is specific to Lepidopteran insects. Cry5Ba resembles the previously reported Cry1Aa toxin structure in that they share a common 3D structure with three domains, but there are some distinctions, with the main differences being located in the loops of domain I. Cry5Ba exhibits a changeable extending conformation structure, and this special structure may also be involved in pore-forming and specificity determination. A fuller understanding of the 3D structure will be helpful in the design of mutagenesis experiments aimed at improving toxicity, and lead to a deep understanding of the mechanism of action of nematicidal toxins.
期刊：
PROCEEDINGS OF THE EDINBURGH MATHEMATICAL SOCIETY,2008年51(2):407-419 ISSN：0013-0915
通讯作者：
Liu, Zhenhai
作者机构：
[Liu, Zhenhai] Cent S Univ, Dept Math, Changsha 410075, Hunan, Peoples R China.;[Liu, Guifang] Hunan City Univ, Dept Math, Yiyang 413049, Hunan, Peoples R China.
通讯机构：
[Liu, Zhenhai] C;Cent S Univ, Dept Math, Changsha 410075, Hunan, Peoples R China.
关键词：
Primary 35B34;47J20;49J40;65N25;elliptic hemivariational inequality;generalized Clarke subdifferential;pseudo-monotone operator;existence of solutions
摘要：
This paper is devoted to the Dirichlet problem for quasilinear elliptic hemivariational inequalities at resonance as well as at non-resonance. Using Clarke's notion of the generalized gradient and the property of the first eigenfunction, we also build a Landesman-Lazer theory in the non-smooth framework of quasilinear elliptic hemivariational inequalities.
摘要：
In this paper, we present an eigenvalue method for testing positive definiteness of a multivariate form. This problem plays an important role in the stability study of nonlinear autonomous systems via Lyapunov's direct method in automatic control. At first we apply the D'Andrea-Dickenstein version of the classical Macaulay formulas of the resultant to compute the symmetric hyperdeterminant of an even order supersymmetric tensor. By using the supersymmetry property, we give detailed computation procedures for the Bezoutians and specified ordering of monomials in this approach. We then use these formulas to calculate the characteristic polynomial of a fourth order three dimensional supersymmetric tensor and give an eigenvalue method for testing positive definiteness of a quartic form of three variables. Some numerical results of this method are reported.
摘要：
The interactions of meso-tetraphenylporphyrin (TPP), meso-tetraphenylporphyrin cobalt(II) (CoTPP) and protein in the presence of a cyclodextrin derivative, heptakis(2,6-di-O-n-octyl)-beta-cyclodextrin (Oc-beta-CD), have been investigated. In the presence of Oc-beta-CD, significant increase of TPP fluorescence was realized, but the increased fluorescence was quenched by CoTPP. To further investigate the fluorescence-quenched system and explore its potential application in bioanalysis, a strategy has been devised to restore the quenching fluorescence of TPP upon interacting with protein. The restoration of TPP fluorescence in the present system is fast and accomplished upon interaction with bovine serum albumin (BSA) or human serum albumin (HSA). On the basis of the spectroscopic measurement and excited state fluorescence lifetime, the mechanism of TPP fluorescence quenching is attributed to formation of a ground-state complex of TPP and CoTPP, and the fluorescence restoration is attributed to the binding of CoTPP with the protein molecule which destroys the aggregate, releasing the free base porphyrin. With optimized conditions, the calibration equations are linear from 0.80 to 75.4 mu g mL(-1) BSA and from 3.20 to 93.2 mu g mL(-1) HSA. The corresponding detection limits are 0.32 mu g mL(-1) for BSA and 1.06 mu g mL(-1) for HSA, respectively The method was used for the direct assay of HSA content in human serum. The result is comparable to that obtained by another method. The recovery from BSA in synthetic sample is also satisfactory.
摘要：
The PI index is a graph invariant defined as the summation of the sums of n(eu)(e vertical bar G) and n(ev)(e vertical bar G) over all the edges e = uv of a connected graph G, i.e., PI(G) = Sigma(e epsilon E(G))[n(eu)(e vertical bar G) + n(ev)(e vertical bar G)], where n(eu)(e vertical bar G), where n(eu)(e vertical bar G) is the number of edges of G lying closer to u than to v and n(eu)(e vertical bar G) is the number of edges of G lying closer to v than to u. An efficient formula for calculating the PI index of polyomino chains is given, and the bounds for the PI index of polyomino chains are established. (C) 2008 Elsevier Ltd. All rights reserved.
期刊：
Microwave and Optical Technology Letters,2008年50(8):2158-2161 ISSN：0895-2477
通讯作者：
Xu, Lan Yun
作者机构：
[Xu, Lan Yun] Hunan City Univ, Dept Phys & Elect Engn, Yiyang 413000, Hunan, Peoples R China.;[Yu, Jian Guo] Beijing No Fiberhome Technol Co Ltd, Beijing 100088, Peoples R China.;[Xu, Hong Yun] S China Univ Technol, Sch Comp Sci & Engn, Guangzhou 510640, Peoples R China.
通讯机构：
[Xu, Lan Yun] H;Hunan City Univ, Dept Phys & Elect Engn, Yiyang 413000, Hunan, Peoples R China.
