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Prediction of GC Retention Times of PBDE Congeners Based on QSRR Xiaotong Zhang1,a, Xin Zhang2,b, Qiang Li3,c, Zhaolin Sun4,d, Lijuan Song5,e and Ting Sun6,f 1,2,4,5 Liaoning Key Laboratory of Petrochemical Engineering, Liaoning Shihua University, Fushun, Liaoning, China 3 College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, China 6 College of Sciences, Northeastern University, Shenyang, Liaoning, China axt.zhang@163.com, bzxliaoshihua@163.com, cqli0218@163.com, dmzdxg-1224@163.com, elsong56@263.net, fsun1th@163.com Keywords: Polybrominated diphenyl ether (PBDE), Quantitative structure retention relationships (QSRR), Gas chromatography (GC).
Therefore quantitative structure retention relationships (QSRR) models were developed to predict retention parameters efficiently by theoretical descriptors computed from chemical structure.
Molecular Descriptors Generation All structures were drawn with the ChemBioDraw 2010 software.
The major contributing molecular descriptors These are presented in Table 2 that GC-RRTs of PBDEs on the seven stationary phases are strongly dependent on the Wiener index, the first topological index used in chemistry.

Introduction The ability to control and manipulate the physical and chemical properties of materials as we desire is one of the challenging issues in chemistry and materials science.
X-ray powder diffraction (XRD) patterns were recorded using a Bruker D8 X-ray diffractometer with Cu Kɑ radiation, and the morphology and structure were determined using scanning electron microscopy (FESEM, JSM-6700F) and transmission electron microscopy (TEM, JEOL 2010).
Structure and Morphology of Nanobelts.
All the peaks of the XRD pattern in Figure 1 could be well indexed to the pure hexagonal structure of Cd(OH)2 (JCPDS. 31-228).

Adsorption characteristics of Hg2+ ions using Fe3O4/chitosan magnetic nanoparticles Bolin Liang1,a 1 Department of Chemistry and Biology, Hezhou University, Hezhou, Guangxi 542800, China a liangbolin01@126.com Keywords: Dialdehyde starch; Magnetic nanoparticles; Adsorption; Fe3O4 Abstract.
Fig. 4 TEM micrographs of Fe3O4/chitosan magnetic nanoparticles (a)and Fe3O4/chitosan magnetic nanoparticles adsorption with mercury ions (b) To confirm the presence of crystalline naked Fe3O4 and Fe3O4/chitosan magnetic nanoparticles, the structure of the magnetic particles was characterized by XRD and the XRD patterns were shown in Fig.5.
There were six well-defined peaks at 30.1°, 35.5°, 43.1°, 53.4°, 57.0°and 62.6° , which was the standard pattern for crystalline magnetite with a spinel structure.
These peaks revealed that the resulting nanoparticles were pure Fe3O4 with a spinel structure.

In this paper, some silane compounds containing Si-Ph bonds (MenPhmSiCl4-n-m, n=0-3, m=1-4)) in the ideal gas state at 298.15 K and 1.013 × 105 Pa were calculated at B3LYP/6-31G* level with Gaussian 03 program[12], to get some thermodynamic parameters such as the standard enthalpy of formation (ΔfHө) and standard free energy of formation (ΔfGө), constant volume heat capacity (CV), entropy (Sө) , molar heat capacity at constant pressure (Cp, m) Calculation methods The structure of phenyl substituted silane derivatives are illustrated in Fig. 1.
Molecular structure of phenyl substituted silane derivatives All calculations were used the Gaussian 03 program on the B3LYP/6-31G * level to obtain the thermodynamic properties parameters of the molecular, including constant-volume heat capacity (CV), entropy (Sө), enthalpy (Hө), free Energy (Gө).
Vibration analysis and calculation of the results showed no imaginary frequency which confirmed that the molecular structure optimized to corresponded to the energy minima.
Acknowledgement This work was financially supported by the National Natural Science Foundation of China (20906038), the Provincial Natural Science Foundation of Zhejiang (Y4090135)，Scientific Research Foundation for talented person of Jiaxing University(NO.70508010) and 2009 Open Foundation of Applied Chemistry Priority subject from Zhejiang University of Technology.

The main feature which makes it very interesting from engineering point of view is the presence of relatively high amount of water in its structure (2-6 wt. %).
Water is entrapped in perlite structure during solidification of hot volcanic lava.
The origin of that is the cellular structure of expanded perlite grains build of thin walls with a lot of empty spaces.
Kurdowski, Chemistry of cement and concrete, PWN/Polski Cement, Cracow/Warsaw, 2010 (in Polish)

Uniaxial compression draws the original fcc structure to the bcc one via tetragonal Bain's path.
Under tensile loading, there is no structure of a higher symmetry along the deformation path and the tensile stress maximum corresponds to tensile instability (the lattice planes perpendicular to the loading axis irreversibly separate).
Our electronic structure calculations were performed using Abinit Simulation Package [6].
Lide (ed.): Handbook of Chemistry and Physics (CRC Press, 2005)

Pyrimidine is one of the most popular N-heteroaromatic compounds incorporated into the structures of many pharmaceuticals.
Super critical water hydrothermal synthesis (SCWHS) is among the most active fields of green chemistry.
Fig. 2: XRD patterns of CuO particles prepared at supercritical condition and calcination of copper nitrate trihydrate Fig. 3: Transmission electron micrographs of CuO nanoparticles RESULT AND DISCUSSION Among methods to prepare nanoparticles, supercritical hydrothermal synthesis is a unique technique to synthesize metal oxide and hydroxide nanocrystals from aqueous solution of metal salts, in which the size, morphology and crystal structure are controllable.
IR spectra of fresh and used nano-CuO catalyst confirmed the fact that the structure and morphology of the catalyst remained the same during the course of the reaction (Fig. 4).

Research on a Novel Amphoteric Polymeric Flocculant p(DMC/NVP/FA) Processing Dyeing Wastewater Yao Ding 1, a, Yanni Jiang 2, Kunhong Yang1 and Ming Zhu 2,b 1Lab, Chengdu Academy of Environmental Sciences, Chengdu 610072, China 2Key Laboratory of Special Waste Water Treatment, Sichuan Province Higher Education System and College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, China adingyao1220@163.com, bzhuming19602003@aliyun.com Keywords: flocculant; dyeing wastewater; CODcr; chroma; intrinsic viscosity; Df Abstract.
Floc structures were Analysized with JSM－7500F field emission scanning electron microscope(Jeol Co.
It can be seen from Fig. 4, Fig. 6 and Fig. 8, the structure of flocs in Fig. 6 is the tightest and the rest two are looser.Higher Df values indicates tighter floc structures.

Synthesis of Titania Nanotubes and Its Application on Oxalic Acid Removal from Aquatic Environment Wen-Churng Lin1, a, Rui Liu2, b, Wein-Duo Yang3, c, Zen-Ja Chung4, d and Hui-Ju Chueng3, e 1 Department of Environmental Engineering, Kun Shan University, Tainan 710, Taiwan, ROC. 2 Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001, PR China 3 Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung, Taiwan, R.O.C 4 Division of Chemical Engineering, Institute of Nuclear Energy Research, Lungtan, Taoyuan 325, Taiwan, ROC alinwc@mail.ksu.edu.tw, bliurui19840601@yahoo.cn, cywd@cc.kuas.edu.tw, dzjchung@iner.gov.tw, ejeol0921@yahoo.com.tw Keywords: Titania nanotubes; Hydrothermal; Photocatalyst; Oxalic acid degradation Abstract.
The characteristics of calcined TiO2 nanotubes were also analyzed: the crystalline phase was identified by an X-ray diffractometer (XRD) and the surface structure and nanotube morphology were examined by a Transmission electron microscope (TEM).
This indicates that different phase structures were obtained after the calcination of the titanate precursors.
The difference in the phase structure of the calcined nanotubes may be attributed to different preparation and post-treatment conditions.

However, it is also important to note that the concentration of different nanoparticles plays a different role in tuning the optical energy band gap [12], which is due to the broadening or narrowing of the valence band or multivalence structures.
Undoubtedly, the incorporation of Au NPs in the glass host cause significant modifications of the network structure and consequently the local environment of RE ions.
The enhancement of photoluminescence originates from the field change on local structure.
Conclusions Nanoglass plasmonics is newly developed very vast and expanding paradigm of nanophotonics and is a unique part of physics/chemistry/materials science because it combines a wealth of scientific challenges with a large variety of near-term applications.