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151.
<正>An electrochemical sensor for the detection of the natural double-stranded DNA(dsDNA) damage induced by PbSe quantum dots(QDs) under UV irradiation was developed.The biosensing membranes were prepared by successively assembling 3- mercaptopropionic acid,polycationic poly(diallyldimethyl ammonium) and dsDNA on the surface of the gold electrode.Damage of dsDNA was fulfilled by immersing the sensing membrane electrode in PbSe QDs suspension and illuminating it with an UV lamp. Cyclic voltammetry was utilized to detect dsDNA damage with Co(phen)_3~(3+) as the electroactive probe.The UV irradiation,Pb~(2+) ions liberated from the PbSe QDs under the UV irradiation and the reactive oxygen species(ROS) generated in the presence of the PbSe QDs also under the UV irradiation were the three factors of inducing the dsDNA damage.The synergistic effect of the three factors might dramatically enhance the damage of dsDNA.This electrochemical sensor provided a simple method for detecting DNA damage,and may be used for investigating the DNA damage induced by other QDs. 相似文献
152.
Facile synthesis of a melt-spinnable polyborazine from asymmetric alkylaminoborazine 总被引:1,自引:0,他引:1
Yong Peng Lei Ying De Wang Yong Cai Song Yi He Li Hao Wang Cheng Deng Zheng Fang Xie 《中国化学快报》2010,21(9):1079-1082
<正>A novel asymmetric alkylaminoborazine monomer,2-propylamino-4,6-bis(methylamino)borazine,was synthesized for the first time,and directly polymerized to give a melt-spinnable polyborazine(PBN).This asymmetric alkylaminoborazine was synthesized by an aminolysis reaction of 2,4,6-trichloroborazine(TCB) with different amines under mild conditions.This route turns out to be much cheaper and simpler than the conventional routes.The chemical composition,structure,molecular weights and ceramic yield were investigated by EA,FTIR,NMR,GPC and TG analysis.The PBN exhibits suitable rheological property for melt-spinning, which suggests that it is a potential precursor for BN fibers. 相似文献
153.
<正>Nitration of 4,4'-biphenyldicarboxylic acid(BPDC) was studied and an aromatic carboxylic acid containing two nitro groups was synthesized and characterized through elemental analysis and IR spectra.Crystal structure of DNBPDC(DNBPDC=2,2'- dinitro-4,4'-biphenyldicarboxylic acid) was determined by X-ray single crystal diffraction and the thermal decomposition was carried out through DSC and TG-DTG analyses. 相似文献
154.
<正>"One-step"method for the synthesis of secondary aliphatic amine substituted nitrobenzaldehyde was developed.In the presence of Pd catalyst,halogenated nitrobenzaldehyde could be smoothly coupled with secondary aliphatic amine to give the target product in hexamethylphosphamide(HMPT) media without the protection of aldehyde groups. 相似文献
155.
HUANG Yu LIU JunLiang ZHANG Ji LIU Qiang HOU JiTing ZHANG Yu ZHANG DaWei LU QiaoSen CHEN ShanYong LIN HongHui & YU XiaoQi Key Laboratory of Green Chemistry Technology Ministry of Education College of Chemistry Sichuan University Chengdu China Key Laboratory of Bio-resources Eco-environment College of Life Sciences China. 《中国科学:化学》2010,(1)
A series of novel molecules with a cyclen(1,4,7,10-tetraazacyclododecane) moiety appended on and bearing different aromatic fragments in the structures were synthesized and characterized.The binding activities of these compounds towards DNA were systematically studied by spectroscopic,viscometric and gel electrophoresis methods.The results suggest that the stacking interaction plays an important role in improving the DNA binding ability of the compounds.The binding modes of the compounds towards DNA are als... 相似文献
156.
FAN Zhi GUO MinJie DONG Bin DIAO ChunHua JING ZuoLiang & CHEN Xin College of Sciences Tianjin University of Science Technology Tianjin China 《中国科学:化学》2010,(5)
The mono-modified β-cyclodextrin derivative,6-O-(4-aminobenzoyl)-β-cyclodextrin(1) ,was synthesized and characterized. We compared its self-assembling behavior with structurally related β-cyclodextrin derivative,6-O-(4-hydroxybenzoyl)-βcyclodextrin(2) ,in aqueous solution and in the solid state using NMR spectroscopy and single crystal X-ray structure analysis. The two complexes displayed different self-assembling behaviors.Complex 1 formed a head-to-tail helical columnar superstructure in which the substit... 相似文献
157.
TANG Ke HONG Xin ZHAO YongHua SONG LiJuan & SUN ZhaoLin School of Material Chemical Engineering Liaoning Institute of Technology Jinzhou China College of Petrochemical Engineering Liaoning University of Petroleum & Chemical Technology Fushun 《中国科学:化学》2010,(1)
Gallium atoms have been introduced into the framework of Y zeolite by treating the zeolite with an aqueous solution of ammonium hexafluoro gallate.Desulfurization of various model fuels containing about 500 μg/g sulfur has been studied over the synthesized Y zeolite(GaAlY).The sulfur adsorption capacity is 7.0,17.4,14.5,16.9,6.9 and 5.8 mg(S)/g adsorbent for thiophene,tetrahydrothiophene(THT),4,6-dimethyldibenzothiophene(4,6-DMDBT),dibenzophiophene(DBT),benzothiophene(BT) and 4-methyldibenzothiophene(4-MDBT... 相似文献
158.
YU YanLi BAI Wei ZHAO KongShuang& ZHOU YunLong College of Chemistry Beijing Normal University Beijing China College of Life Science 《中国科学:化学》2010,(3)
Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2+ solution to Microcystis aeruginosa.It was found that 0.04 mM Cu2+ had no effect on dielectric increment,whereas the Cu2+ concentrations above 0.1 mM decreased the value of Δε/Δε intact.The toxic effect of Cu2+ on M.aeruginosa cells was time-dependent and concentration-dependent.There was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2+ at the concentrations higher than 0... 相似文献
159.
空穴传输基团修饰的吡嗪铱配合物的合成及其发光性质 总被引:1,自引:0,他引:1
设计合成了空穴传输性咔唑基团修饰的吡嗪配体, 2,3-二(4-(9-咔唑基甲基)苯基)-5-甲基吡嗪(CzMPMP)及其铱配合物Ir(CzMPMP)2(acac)(acac: 乙酰丙酮). 用核磁共振(NMR)、质谱、元素分析等方法对其进行了表征, 并用紫外-可见吸收光谱、液相和固相光致发光光谱对其光学性质进行了研究. 通过与没有咔唑取代基的2,3-二苯基-5-甲基吡嗪铱配合物Ir(DPMP)2(acac)进行对照, 说明咔唑基团对配合物的光学性质有显著影响. 不含咔唑取代基的配合物Ir(DPMP)2(acac)的固态光致发光光谱中存在很强的激活双体(excimer)峰, 而Ir(CzMPMP)2(acac)的固态光致发光光谱中未发现有激活双体峰; 并且在溶液中, 含有咔唑取代基的配合物Ir(CzMPMP)2(acac)较Ir(DPMP)2(acac)的光致发光强度有显著提高. 这些结果说明咔唑基团的空间位阻可以有效阻止配合物成膜时产生激活双体, 从而消除发射峰红移现象并提高发光效率. 相似文献
160.
FAN CuiLing LEI JianGuo & SHAN XiuLing School of Sciences Nantong University Nantong China College of Mathematics Information Science Hebei Normal University Shijiazhuang 《中国科学 数学(英文版)》2011,(1)
Difference systems of sets (DSSs) are combinatorial configurations which were introduced in 1971 by Levenstein for the construction of codes for synchronization. In this paper, we present two kinds of constructions of difference systems of sets by using disjoint difference families and a special type of difference sets, respectively. As a consequence, new infinite classes of optimal DSSs are obtained. 相似文献