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Fadong Yan Tomoya Higashihara Ravi Mosurkal Lian Li Ke Yang Rudolf Faust 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):910-913
Self organization and redox behavior of a ferrocene containing triblock copolymer, poly(vinylferrocene)-block-poly(isobutylene)-block-poly(vinylferrocene), with narrow molecular weight distribution in solutions and in thin films were investigated. Dynamic light scattering studies of the block copolymer in dilute solutions indicated that the polymer chains aggregated at relatively low concentrations. The aggregations of polymer chains were observed in toluene, as well as in tetrahydrofuran at concentrations as low as 0.014 mg/mL and 0.0045 mg/mL, respectively. Thin films of the copolymer showed reversible single electron redox behavior, similar to that of ferrocene. Morphology and micro-phase separation of the copolymer was analyzed by transmission electron microscopy. 相似文献
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Soumitra Satapathi Lian Li Robinson Anandakathir Lynne A. Samuelson Jayant Kumar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1049-1054
Nanoparticles of a regioregular and soluble polythiophene were fabricated by mini-emulsion technique. The fabricated nanoparticles were characterized by optical spectroscopy and dynamic light scattering. The fluorescence quenching of these fabricated nanoparticles with 2,4-dinitrotolune (DNT) in aqueous and organic solutions was investigated. Significant fluorescence quenching was observed. The Stern-Volmer constants were determined to be higher than that of the bulk polymer in solution, indicating that the nanoparticles provide better sensitivity in DNT sensing. Strong two-photon-induced fluorescence was measured from these nanoparticles. 相似文献
106.
Fabrication of gold nano‐patterns has been demonstrated employing surface relief structures created on films of an azobenzene‐functionalized polymer as templates. The surface relief templates were photoinscribed on the azopolymer films in one‐step with two laser beams. Thin layers of gold were over‐coated on the polymer templates by thermal evaporation. Gold lines of a few hundred nanometer width were successfully fabricated by pyrolyzing the azobenzene polymer. Sub‐micron gold dots were also created. The resulting gold structures exhibited the same periodicity as the polymer templates. 相似文献
107.
We have designed and synthesized a new ruthenium complex, [(5‐amino‐1,10‐phenanthroline)bis(4,4′‐dicarboxylic acid‐2,2′‐bipyridine)]ruthenium(II) by introducing two types of ligands, 5‐amino‐1,10‐phenanthroline and 4,4′‐dicarboxylic acid‐2,2′‐bipyridine. We investigated the electronic, spectroscopic, electrochemical, and photovoltaic properties of the Ru(II) complex. The short‐circuit current density and overall solar‐to‐electric energy conversion efficiency of photovoltaic cells made with this Ru(II) complex were found to be 8.9 mA/cm2 and 2.1%, respectively. A series of analogous Ru(II) complexes have also been synthesized and investigated to compare the effects of functional groups on various ligands. HOMO‐LUMO energies and molecular orbital surfaces have been investigated using semiempirical quantum chemical methods. 相似文献
108.
Hongmei Yang Zong‐Jun Li Debin Wan Wenhui Lian Shuying Liu 《Journal of mass spectrometry : JMS》2013,48(5):539-543
In this work, laser‐enhanced in‐source decay (LEISD) technique of matrix‐assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI‐FT‐ICR‐MS) was used to distinguish reducing and nonreducing carbohydrates. Interestingly, easier cleavage of (1 → 2)‐linked glycosidic bonds for nonreducing carbohydrates containing D‐fructofuranosyl units was observed in MALDI‐FT‐ICR‐MS, which was in agreement with the result of theoretical calculation by the software package Gaussian 09. Importantly, no cross‐ring cleavage of fructofuranosyl residues was detected in the LEISD spectra of nonreducing carbohydrates. LEISD method therefore offers an attractive alternative for fast and efficient differentiation of reducing and nonreducing carbohydrates, and the positions of nonreducing monosaccharide residues in a carbohydrate chain could be easily speculated. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
109.
运用UPLC-MS联用技术对空白对照组、柴胡总皂苷(SS)组大鼠在给药后第3天和第5天的尿液样本进行分析检测,获得了以质荷比和保留时间为变量的矩阵数据。据此建立各组大鼠的尿液代谢轮廓图,并利用主成分分析(PCA)建立了SS的代谢组学毒性模型。结合肝组织病理,探讨了柴胡总皂苷的急性肝毒性。对于SS组与正常组,大鼠尿液代谢轮廓图表现出了一定的差异。在代谢组学毒性模型中,给药第3天和第5天的PCA分类均偏离正常组,而第5天的偏离程度强于第3天。同时,在第5天的肝组织病理切片中发现了组织病变。由此表明,给药组大鼠的代谢组偏离了正常组,这种偏离正是肝急性毒性的表现,且给药到第5天的肝毒性强于第3天,表明肝毒性与给药累积剂量呈正相关,表现出了明显的急性和累积肝毒性。 相似文献
110.
以城市污水处理厂剩余污泥为原料,添加微量钛铁矿,采用氯化锌活化法制备复合吸附剂,并考察了其对含Cr(Ⅵ)废水的处理效果。研究表明:钛铁矿添加量1.5%、氯化锌浓度3 mol/L、固液比1∶2、活化温度550℃和活化时间40 min时,复合吸附剂碘吸附值可达523.24mg/g,比表面积为285.003 m2/g,相对于不添加钛铁矿的纯污泥吸附剂分别提高了27.95%和43.08%;吸附Cr(Ⅵ)废水研究表明,当pH为1.5、吸附剂用量为4 g/L、吸附时间为120 min时,吸附率可达99.17%,吸附量为12.4 mg/g。 相似文献