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The frequencies of high frequency quasi-periodic oscillations in two different frames in black hole LMXBs

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Research in Astronomy and Astrophysics 2011年第11期11卷 1327-1335页

作者： Chang-Sheng Shi College of Material science and chemical engineering,Hainan university,Hainan 570228,china key laboratory of Modern Astronomy and Astrophysics,nanjing university,nanjing 2.0093,china College of Material science and chemical engineering Hainan University Hainan 570228 China key laboratory of Modern Astronomy and Astrophysics Nanjing University Nanjing 210093 China

We discuss the modes of the Alfvén waves in the accretion disk with a toroidal magnetic field in black hole low mass X-ray binaries in a rotating frame. By solving the perturbed general relativistic magnetohydrodynamic equations in the rotating frame, we find two stable modes of the Alfvén wave which are the same as those in the fiducial observer frame. This gives a feasible way to transform between the two different frames, which validates the possible Alfvén wave modes in the accreting celestial bodies with a toroidal magnetic field.

关键词： accretion accretion disks-magnetohydrodynamics-relativity

Analysis of variance for testing method of cement in determination of strength

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Progress in Natural science:Materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State key laboratory of Materials-Oriented chemical engineering,College of Material science and engineering, nanjing university of Technology,nanjing 210009,china State key laboratory of Materials-Oriented chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

The interaction between furosemide-palladium (Ⅱ) chelate and basic triphenylmethane dyes by resonance Rayleigh scattering spectra and resonance non-linear scattering spectra and their analytical applications

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science china chemistry 2010年第8期53卷 1767-1777页

作者： LI CuiXia,LIU ShaoPu,LIU ZhongFang & HU XiaoLi key laboratory on Luminescence and Real-Time Analysis,ministry of education school of chemistry and chemical engineering,Southwest university,Chongqing 400715,china key laboratory on Luminescence and Real-Time Analysis Ministry of Education school of chemistry and chemical engineering Southwest University Chongqing China

In pH 4.5-7.0 Britton-Robinson buffer solution,furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic *** chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV),crystal violet (CV),methyl violet (MV),methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association *** not only resulted in the change of absorption spectra,but also led to the significant enhancement of resonance Rayleigh scattering (RRS),second-order scattering (SOS) and frequency doubling scattering (FDS).The maximum RRS wavelengths were located at 324 nm for the EV,CV and MV system,and 340 nm for the BG and MeG *** maximum SOS wavelengths were located at 550 nm for the EV,CV,BG and MeG system,and 530 nm for the MV *** maximum scattering peaks of all the systems were at 392 nm for *** enhanced RRS,SOS and FDS intensities were directly proportional to the concentration of *** detection limits for the different dye systems were 0.3-4.9 ng mL-1 for the RRS method,3.2-33.1 ng mL-1 for the SOS method and 9.0-85.7 ng mL-1 for the FDS *** methods could be used for the determination of trace amounts of *** effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption,RRS,SOS and FDS have been *** optimum conditions of these reactions,the influencing factors and the analytical properties have been *** influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high *** on the aforementioned research,the highly sensitive,simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established,which could be applied to the determination of FUR in tablet,injection,human serum and urine *** composition and structure of the ternary ion-association complex and the reaction mechanism were discusse

关键词： furosemide basic triphenylmethane dyes palladium (Ⅱ) resonance Rayleigh scattering resonance non-linear scattering

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:Materials International 2011年第3期21卷 246-253页

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

Fluorescence determination of platinum with dibromohydroxyphenyl-fluorone in microemulsion after separation and enrichment by sulfhydryl dextrose gel

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Rare Metals 2008年第1期27卷 101-105页

作者： LI Huizhi ZHAI Yubo ZHAI Diantang school of chemistry and chemical engineering Jinan University Jinan 250022 China school of life science Nanjing University Nanjing 210093 China

A new fluorescence quenching method has been developed for the determination of platinum in nonionic microemulsion *** method is based on the fact that platinum can form a stable chelate with dibromohydroxyphenyl-fluorine（DBHPF） when they are in the molar ratio of 1：2 in the nonionic microemulsion *** optimum conditions,the system,having the maximum excitation and emission wavelengths at 468 nm and 532 nm,respectively,shows constant fluorescence intensity in the pH range of 3.5-4.0 and high selectivity and sensitivity as well as low interference from foreign ***,this fluorescence intensity is a linear function of Pt（IV） concentration in the range of 0.002-1.00 μg·mL^-1 and the limit of detection is 2.90 ng·mL^-1.

关键词： analytical chemistry separation and enrichment fluorescence determination microemulsion platinum(IV)

Influence of steric and intramolecular inductive effects on the variable trends in R-X (R=Alkyl) bond dissociation energy

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science china chemistry 2009年第7期52卷 943-951页

作者： CAO ChenZhong school of chemistry and chemical engineering, Hunan university of science and Technology, Xiangtan 411201, china school of chemistry and chemical engineering Hunan University of Science and Technology Xiangtan 411201 China

The question "why are the variation trends of R-X bond dissociation energy different?" is answered. The R-X bond dissociation energy (BDE) may be influenced by three main factors: the C-X intrinsic bond energy, the 1,3 geminal repulsion, and the intramolecular charge-induced dipole. In the presence of atom X, the variation trend of BDE in R-X (R= Me, Et, i-Pr, t-Bu) is dominated by two factors, the 1,3 geminal repulsion and the intramolecular charge-induced dipole. The former decreases the R-X BDE, and the latter either increases or decreases the R-X BDE. For the series of R-X with the R-C bond (such as R-Me, R-CH == CH2, R-C≡CH, and R-CN), the 1,3 geminal repulsion decreases the R-X BDE, and the variation trends of R-C BDE decrease from Me to t-Bu. As regards the series of R-X (such as R-H, R-BH2, and R-SiH2) in which the electronegativity of atom X is smaller than that of the carbon atom, the above two factors decrease the R-X BDE, and the variation trends of the R-X BDE decrease from Me to t-Bu. As to the series of R-X (such as R-F, R-OH, R-Cl, R-Br, R-I, and R-NH2) in which the electronegativity of atom X is larger than that of the carbon atom, the 1,3 geminal repulsion decreases the R-X BDE, while the intramolecular charge-induced dipole increases the R-X BDE. In this case, the variation trends of R-X BDE depend on the competition of the two factors. As a result, some of them (e. g., R-F, R-OH) increase from Me to t-Bu, some (e. g., R-I) decrease from Me to t-Bu, and some (e. g., R-Br) change very little.

关键词： bond dissociation energy charge-induced dipole geminal repulsion ionic configuration

Two novel interpenetrated zinc(Ⅱ) and cadmium(Ⅱ) coordination polymers based on 4-imidazole-benzoate:Syntheses,crystal structures and properties

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science china chemistry 2009年第4期52卷 459-464页

作者： BAI ZhengShuai,CHEN ShuiSheng,ZHANG ZhengHua,CHEN ManSheng,LIU GuangXiang & SUN WeiYin State key laboratory of Coordination chemistry,Institute of Coordination chemistry,school of chemistry and chemical engineering,nanjing university,nanjing 2.0093,china State key laboratory of Coordination chemistry Institute of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing China

Two novel interpenetrated coordination polymers,[Zn(IBA)2]n (1) and {[Cd(IBA)2(H2O)].4H2O}n (2),have been synthesized by using 4-imidazole-benzoic acid (HIBA) as ligand under hydrothermal con-ditions. Complex 1 crystallizes in a chiral space group and has a two-fold interpenetrated 2D network structure with (4,4) topology,while complex 2 is a 3D porous dia network with four nets interpene-trating each other. The SHG activity of 1 and the photoluminescent property of 2 have been investi-gated.

关键词： coordination polymer interpenetration crystal structure photoluminescence property

Aptamer-based competitive electrochemical assay of small biomolecules

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science china chemistry 2011年第5期54卷 822-826页

作者： ZHANG YuYong,XIANG Yun,CHAI YaQin & YUAN Ruo key laboratory on Luminescence and Real-Time Analysis,ministry of education school of chemistry and chemical engineering,Southwest university,Chongqing 400715,china 1. key laboratory on Luminescence and Real-Time Analysis Ministry of Education school of chemistry and chemical engineering Southwest University Chongqing 400715 China

A convenient aptamer-based competitive electrochemical biosensor for a small biomolecule,adenosine,was described. The sensing surface was fabricated by self-assembly of an aptamer/mercaptohexanol monolayer on a gold disk electrode. The principle of this aptasensor is based on the competition between an adenosine target molecule and a ferrocene-conjugated signaling DNA strand for the aptamer binding site on the sensing surface. Due to the competitive nature of this assay,the electrochemical responses of the surface captured ferrocene are inversely proportional to log[adenosine] in the range from 0.05 to 3.2 μM,with a detection limit of 25 nM. Moreover,the aptasensor also shows high selectivity for adenosine. The proposed aptasensor thus holds great potential for the detection of other small biomolecules.

关键词： aptamer adenosine biosensor competitive assay differential pulse voltammetry

Progress in the development of techniques based on light scattering for single nanoparticle detection

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science china chemistry 2011年第8期54卷 1244-1253页

作者： ZHU ShaoBin, WANG Shuo, YANG LingLing, HUANG TianXun & YAN XiaoMei Department of chemical Biology, College of chemistry and chemical engineering key laboratory for chemical Biology of Fujian Province key laboratory of analytical science, Xiamen university, Xiamen 361005, china 1. Department of chemical Biology College of Chemistry and Chemical Engineering key laboratory for chemical Biology of Fujian Province key laboratory of analytical science Xiamen University Xiamen 361005 China

Nanoparticles have recendy attracted extensive attention in view of their great potential in biomedicine and bioanalytical applications. Single particle detection via light scattering offers a simple and efficient approach for the size, size distribution, and concentration analysis of nanoparticles. In particular, intrinsic heterogeneity or rare events masked by ensemble averaging can be revealed. However, the sixth power dependence of Rayleigh scattering on particle size makes it very challenging to detect individual nanoparficles of small sizes. This article is intended to provide an overview of recent progress in the development of techniques based on light scattering for the detection of single nanoparticles.

关键词： light scattering single particle detection nanoparticles confocal correlation spectroscopy flow cytometry