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Effect of Nano-anatase TiO_2 on spectral characterization of PhotosystemⅡParticles from Spinach

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Chemical Research in Chinese Universities 2005年第2期21卷 196-200页

作者： HONGFa-shui YANGPing GAOFeng-qing LIUChao ZHENGLei YANGFan ZHOUJuan CollegeofLifeSciences CollegeofChemistryandChemicalEngineering SuzhouUniversitySuzhou215006P.R.China

The photosystem Ⅱ(PSⅡ) particles were purified by means of nano-anatase TiO_2 treatment of spinach and studied by spectroscopy. The results show that the electron transport and the oxygen-evolving rate of PSⅡ are accelerated after it has been treated with nano-anatase TiO_2; the UV-Vis absorption spectrum of PSⅡ particles is increased; the red shift of fluorescence emission peak of PSⅡ is 2 nm; the peak intensity is decreased; the PSⅡ signal Ⅱs of low temperature electron paramagnetic resonanace(EPR) spectrum is intensified under light, and the PSⅡ circular dichroism(CD) spectrum is similar to that of control. It is suggested that nano-anatase TiO_2 might bind to the PSⅡ reaction center complex and intensify the function of the PSⅡ electron donor, however, nano-anatase TiO_2 treatment does not change the configuration of the PSⅡ reaction center complex.

关键词： Nano-anatase TiO_2 Spinach PhotosystemⅡ spectral characterization

Preparation and spectral characterization of 3-Benzyl-6-aryl-1,2,4-triazolothiadiazoles

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Chemical Research in Chinese Universities 2002年第3期18卷 280-283页

作者： ZHANG Li xue ZHANG An jiang CHEN Guang CHEN Fei yu JIANG Yi ping ZHANG Zi yi Department of Chemistry Wenzhou TeachersCollegeWenzhou 325003P.R.China Department of Chemistry Lanzhou UniversityLanzhou 730000P.R.China

Benzyl 4 amino 5 mercapto 1,2,4 triazole reacted with aromatic acids in the presence of phosphorus oxychloride, yielding a series of new compounds, i.e. , 3 benzyl 6 aryl 1,2,4 triazolothiadiazoles, each of which has an active methylene at 3 position. The structures of all the title compounds were confirmed by elementary analysis, IR, 1H NMR and 13 C NMR spectra.

关键词： 3-Benzyl-6-aryl-1,2,4-triazolo[3,4-b]thiadiazoles Preparation spectral characterization

A spectral characterization of the S-clique Extension of the Square Grid Graphs

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A Spectral Characterization of the S-clique Extension of the...

作者： Muhammad Riaz 中国科学技术大学

学位级别：硕士

This thesis focuses simultaneously on two problems in spectral graph theory,known as spectral characterization of graphs and characterization of distance regular graphs from their intersection *** particular,we show that any co-edge-regular graph which is cospectral with the s-clique extension of the t × t-grid is the s-clique extension of the t × t-grid,if t ≥ 11（S + 1）3（s + 2）,（s ≥ 2）.Gavrilyuk and Koolen used a weaker version of this result to show that the Grassmann graph Jq（2D,D）is determined by its intersection array as a distance-regular graph,if D＞20 and if q ≥ 9,then D＞*** thesis consist on four chapters and are organized as follows:In Chapter 1,we discuss the origin and motivation of our *** results are provided to understand its *** 2 focuses on defining all the necessary termi-nologies and *** important concepts such as interlacing,equitable partitions,clique extension of square grid graphs are *** upper bound on the order of a clique in a graph cospectral with the s-clique extension of the square grid graphs,say（?）,is *** Chapter 3,we present the proof of our *** 4 comprises conclusion and future work.

关键词： Co-edge-regular graph Eigenvalue Few eigenvalues spectral characterization

Flux Growth and spectral characterization of LiLa(MoO4)2 and Nd:LiLa(MoO4)2 Crystals

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Journal of the Chinese Ceramic Society 2014年第1期1卷 59-62页

作者： ZHANG Yang LI Jing JIANG Huaidong ZHAO Xian WANG Jiyang Robert BOUGHTON State Key Laboratory of Crystal Materials Shandong University Department of Physics and Astronomy Bowling Green State University

LiLa(MoO4)2, and Nd:LiLa(MoO4)2 crystals were grown by a spontaneous nucleation method. The crystals obtained were characterized by X-ray powder diffraction, derivative differential thermal analysis, Fourier transform infrared spectroscopy, UV–visible diffuse reflectance spectroscopy, and fluorescence spectroscopy, respectively. The electronic structure of LiLa(MoO4)2 was calculated based on the density functional theory, indicating that it has a direct band gap of 2.57 e V. Theoretically, the band structure and density of states reveal that the optical properties of LiL a(MoO4)2 are mainly determined by the Mo 4d orbital.

关键词： laser crystal flux growth electronic structure spectral characterization

On the Laplacian spectral characterization of some unicyclic graphs

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On the Laplacian spectral characterization of some unicyclic...

spectral characterizations of Veronese Surface in S^4

2011 World Congress on Engineering and Technology(CET 2011)

作者： Shengbiao Hu Department of Mathematics Qinghai Nationalities University Xining 810007 P.R.China

A graph G is said to be determined by its Laplacian spectrum if any graph having the same spectrum as G is isomorphic to G.A graph is called unicyclic if its the number of edges equals the number of *** this paper,we ... 详细信息

关键词： Laplacian spectra of graphs Cospectral graphs spectral characterization Starlike trees Unicyclic graphs

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Journal of Shanghai University(English Edition) 2001年第1期5卷 29-30页

作者： ZHENGYong－ai LIUYu－rong 等 DepartmentofMathematics CollegeofScienceShanghaiUniversityShanghai200436China DepartmentofMathematics YangzhouUniversityYangzhou225003China

In this paper, we prove that the Veronese surface can be determined by the 1 spectrum of the Laplace operator.

关键词： minimal submanifold spectral characterization Veronese surface second fundamental form

Synthesis and Crystal Structure of 1,4-Dimethyl-2,5-di{[2’-(3-pyridylmethylamino-formyl)phenoxyl]methyl}benzene Perchlorate

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Chinese Journal of Structural Chemistry 2008年第4期27卷 451-454页

作者： TANG Kuan-Zhen TANG Yu LI Ya-Fei LIU Wei-Sheng TAN Min-Yu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

The title compound, 1,4-dimethyl-2,5-di { [2′-（3-pyridylmethylaminoformyl）phenoxyl]- methyl}benzene perchlorate （C36H36Cl2N4O12, Mr = 787.59）, has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal crystallizes in the orthorhombic system, space group Pbca with a = 14.366（4）, b = 15.159（4）, c = 16.443（5）A, V = 3580.9（17）/A3 Z = 4, De = 1.461 g/cm^3, /t = 0.253 mm^-1, F（000） = 1640, R = 0.0618 and wR = 0.1525 for 1615 observed reflections （I 〉 2σ（I））. In the structure of the title compound, a two-dimensional supramolecular layer is formed via intermolecular hydrogen bonding interactions.

关键词： 2,5-dimethyl-l,4-di{ [2′-(3-pyridylmethylaminoformyl)phenoxyl]methyl)benzene,synthesis spectral characterization crystal structure

Prevention of La^(3+) on DNA Damage Caused by Hg^(2+) from Fish Intestines

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Journal of Rare Earths 2007年第2期25卷 243-248页

作者：洪法水王玲刘超苏明玉黄浩陈亮 College of Life Sciences Library Suzhou University

The aim of this study was to investigate the effects of rare earth elements （REEs） in preventing Hg^2＋ pollution, using fish intestinal DNA in vitro and study the mechanism of the interactions between Hg^2＋ , La^3＋ , the mixture of La^3＋ and Hg^2＋ and DNA by spectroscopy. The interactions between Hg^2＋ , La^3＋ , the mixture of La^3＋ and Hg^2＋ and DNA from fish intestine in vitro was investigate by using absorption spectrum and fluorescence emission spectrum. Ultraviolet absorption spectra indicated that the addition of Hg^2＋ , La^3＋ , and the mixture of La^3＋ and Hg^2＋ to DNA generated obvious hypochromic effect. Meanwhile, the 205.2 nm peak of DNA blue and the 258.2 nm peak of DNA red shifted. The hypochromic effect and peak shift was caused by these ions in an order of Hg^2＋〉 Hg^2＋＋ La^3＋〉 La^3＋ . The fluorescence emission spectra showed that as the addition of Hg^2＋ , La^3＋ , and the mixture of La^3＋ and Hg^2＋ , the emission peak at about 416.2 nm of DNA did not obviously change, but the fluorescence intensity reduced gradually with the order in treatment was Hg^2＋〉 Hg^2＋〉 La^3＋〉 La^3＋ . Hg^2＋ , La^3＋ , and the mixture of La^3＋ and Hg^2＋ had 1.12, 0.58, and 0.81 binding sites to DNA, the fluorescence quenching of DNA caused by them all attributed to static quenching. The binding constants KA of binding sites were 3.82×10^4 and 4.22×10^2 L·mol^-1 ; 2.50×10^4 and 2.95×10^3 L·mol^-1 ; 3.05×10^4 and 1.00×10^3 L·mol^-1. The results showed that La^3＋ could relieve destruction caused by Hg^2＋ on the DNA structure.

关键词： Hg^2+ , La^3+ fish intestinal DNA spectral characterization binding constants rare earths

Preparation and Crystal Structure of 3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H- 1,2,4-triazolo[3,4-b][1,3,4 ]thiadiazine

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Chemical Research in Chinese Universities 2005年第1期21卷 69-72页

作者： ZOUKai-huang ZHANGLi-xue ZHANGAn-jiang LEIXin-xiang HUANGHui-hua ZHANGZi-yi SchoolofChemistryandMaterialsScience WenzhouNormalCollegeWenzhou325027P.R.China／／DepartmentofBiologyandChemistryFujianEducationalCollegeFuzhou350001P.R.China SchoolofChemistryandMaterialsScience WenzhouNormalCollegeWenzhou325027P.R.China CollegeofChemistryandChemicalEngineering LanzhouUniversityLanzhou730000P.R.China

3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H-1,2,4-triazolo[3,4-b][1,3,4] thiadiazine, C 16H 11N 5O 3S, was prepared by the cyclization of 3-(2-hydroxyphenyl)-4-amino-5-mercapto-1,2,4-triazole with 2-bromo-4-nitroacetophenone. The compound was characterized by means of elemental analysis, IR, 1H NMR, 13C NMR, mass spectrometry, and X-ray diffraction. The compound crystallizes in a monoclinic system with space group C c, a=2.1853(4) nm, b=2.1192(5) nm, c=1.3526(3) nm, β=95.21(2)°, V=6.238(2) nm3 , D calcd.=1.505 Mg/m3, Z=16, F(000)=2916, R 1=0.0501, wR 2=0.0427. A comparison between the crystal structures of 1,2,4-triazolo[3,4-b] [1,3,4] thiadiazine and 1,2,4-triazolo[3,4-b][1,3,4] thiadiazole was made in the structural view. A two-dimensional network is formed by hydrogen bonds and π-π stacking interactions.

关键词： Triazolothiadiazine Preparation spectral characterization Crystal structure π-π stacking interaction