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981.
Zhuoshi Wang Junjie Cui Yongri Liang Tie Chen Myongsoo Lee Bingzhu Yin Long Yi Jin 《Journal of polymer science. Part A, Polymer chemistry》2013,51(23):5021-5028
T‐shaped coil–rod–coil oligomers, consisting of a dibenzo[a,c]phenazine unit and phenyl groups linked together with acetylenyl bonds at the 2,7‐position of dibenzo[a,c]phenazine as a rigid segment have been synthesized. The coil segments of these new molecules composed of poly(ethylene oxide) (PEO)–poly(propylene oxide) (PPO) incorporating lateral methyl groups between the rod and coil segment and two flexible alkyl groups connecting with the rigid segment at the 4,6‐position of dibenzo[a,c]phenazine, respectively. The experimental results reveal that the length of the flexible PEO coil chain influence construction of various supra‐nanostructures from lamellar structure to rectangular columnar structure. It is also shown that introduction of different length of alkyl side chain groups in the backbone of the T‐shaped molecules affect the self‐organization behavior to form hexagonal perforate layer or oblique columnar structures. In addition, lateral methyl groups attached to the surface of rod and coil segments, dramatically influence the self‐assembling behavior in the crystalline phase. T‐shaped molecules containing a lateral methyl group at the surface of rod and PEO coil segments, self‐assemble into 3D body‐centered tetragonal structures in the crystalline phase, while molecules without a lateral methyl group based on PEO coil chain self‐organize into 2D oblique columnar crystalline structures. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 5021–5028 相似文献
982.
Xinyi Cui Xiaogang Chu Zweigenbaum Jerry A. Yanyan Fang Wei Yong Yun Ling 《Chromatographia》2010,71(1-2):139-142
This study evaluated the screening of Sudan dyes in salty egg using liquid chromatography/time-of-flight mass spectrometry (LC–TOF-MS). With this technology, accurate mass measurements were made to generate elemental compositions of ions and to provide complementary structural information. This approach is useful for the elucidation of organic pollutants at trace levels in complex food extracts and in the present study salty egg samples were analyzed for the presence of Sudan IV. TOF accurate mass elemental composition data of Sudan IV were found to be crucial for structural elucidation which was applied to the investigation of nine salty egg samples.
相似文献983.
Haitao Zhang Zaihang Zheng Xuejun Cui Hongyan Wang Mei Han 《Journal of mathematical chemistry》2010,48(3):720-732
In order to quantify and predict the water resistance of membrane, a multi-scales association model was built up based on
the Fick’s second law. Two water resistance indexes, balance time and seepage velocity, were put forward and calculated by
the model for measuring the property of membrane water resistance. The association model linked macro-scale factors and micro-scale
parameters together. The influence of macro-scale factors, environmental temperature and membrane thickness, and micro-scale
parameters, water molecules diffusivity, membrane saturated water absorption rate and water escape concentration, were discussed.
The properties of water resistances for two groups including 10 waterborne acrylate membranes samples were measured for validating
the indexes calculated by the model. The well consistency between the results of calculations and experiments proved that
the method of multi-scales association modeling for quantifying and predicting the membrane water resistance was feasible. 相似文献
984.
985.
The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst system. This system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene (T p = 20 °C, 98.2%; T p = ?20 °C, > 99%). Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000), reaching high number-average molecular weight (M n = 1582 kg/mol) and relatively narrow molecular weight distribution (PDI = 1.68), which was, however, influenced by the amount and bulkiness of aluminum alkyls. Dynamic investigation of the polymerization was performed, which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion, suggesting, in some degree, the polymerization with this catalytic system was controllable. 相似文献
986.
The mechanism of magnetic exchange interaction in an interesting CuII coordination polymer with the CuI2X2 (X = I or Br) moiety bridge is investigated by the calculations based on density functional theory combined with the broken-symmetry approach (DFT-BS). Surprisingly, different from the experiment results, the calculations reveal that the complex between the magnetic CuII centers has a fairly weak antiferromagnetic interaction for the long distance (∼10 Å). The analyses show of the molecular orbitals and the spin density distribution favor the very weak antiferromagnetic coupling interactions of the systems. 相似文献
987.
988.
Haixin Cui Jianfang Jiang Wei Gu Changjiao Sun Donglai Wu Tao Yang Guochen Yang 《Photochemistry and photobiology》2010,86(5):1135-1139
This study was conducted to investigate efficiency of TiO2nanomaterial as a novel environment-friendly disinfectant to control avian influenza (AI) by its photochemical sterilization ability. Anatase nano-TiO2sol, a neutral, viscous aqueous colloid of 1.6% TiO2, was synthesized from peroxotitanic acid solution according to the Ichinose method. Transmission electron microscope images showed that the TiO2particles were spindle-shaped with an average size of 50 nm. X-ray diffraction patterns revealed that the crystal phase of TiO2particles was anatase type with photocatalytic effect. A photocatalytic film of nano-TiO2sol was tested as a means of inactivating H9N2avian influenza virus (AIV). Inactivation capabilities were examined with 365 nm ultraviolet (UV) radiation under black light by adjusting the UV intensity, the UV irradiation time and the quantity of AIV. The titer change of AIV was determined by hemagglutination tests. Cytopathic effect of Madin Darby canine kidney (MDCK) cells was monitored by inverted fluorescence microscope. The results showed that anatase nano-TiO2sol significantly inactivated AIV under UV irradiation of 365 nm. The inactivation of AIV viruses reached up to 100%. Therefore, anatase nano-TiO2sol is a potentially environment-friendly antivirus agent to prevent AI. 相似文献
989.
WANG Cui ZHANG Quan ZHANG XiaoFeng LIU Jing & LIU WeiPing College of Biological Environmental Engineering Zhejiang University of Technology Hangzhou China Key Laboratory of Environmental Remediation Ecosystem Health Ministry of Education College of Environmental Resource Sciences Zhejiang University Hangzhou China 《中国科学:化学》2010,(5)
Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The re... 相似文献
990.
We study a class of symmetric discontinuous Galerkin methods on graded meshes. Optimal order error estimates are derived in both the energy norm and the L 2 norm, and we establish the uniform convergence of V-cycle, F-cycle and W-cycle multigrid algorithms for the resulting discrete problems. Numerical results that confirm the theoretical results are also presented. 相似文献