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Monodispersed nano-Pd particles were prepared by sonochemical reduction of a 1∶12 molar mixture of palladium(Ⅱ) chloride(PdCl2), and sodium dodecyl sulfate (SDS) in double deionized aqueous solution. The reducing substance was characterized by transmission electron microscopy (TEM) with selected area electron diffraction (SAED), Fourier transform infrared (FTIR) and X-ray photo electron specstropy analysis (XPS). The results show that the reduction of Pd(Ⅱ) to metallic Pd is achieved and that the obtained suspensions have a long life period. The Pd nanoparticles are highly dispersed and uniform in size (in the range of 1~10 nm). The protective effect of SDS for Pd nanoparticles was investigated and the results indicate that there are interactions between Pd and SDS. 相似文献
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1 INTRODUCTION The bimetallic nanoclusters are of standing inte- rest since they can exhibit catalytic, electronic and optical properties distinct from those of corre- sponding pure nanoclusters[1~4]. Palladium and pla- tinum, well known for their catalytic properties, are often used as the catalyst in different fuel cells[5~8]. Several experimental results illustrate that for the oxygen reduction reaction (ORR), which is one of the primary reactions taking place in many fuel cells and… 相似文献
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A novel assay of γ-globulin (γ-IgG) with a sensitivity at the nanogram level is proposed based on the measurement of enhanced resonance light-scattering (RLS) signals resulting from the interaction of functionalized nano-HgS with γ-globulin. At pH 5.03, the RLS signals of functionalized nano-HgS were greatly enhanced by γ-globulin in the region of 200-700 nm characterized by the peak around 362 nm. Linear relationship can be established between the enhanced RLS intensity and γ-globulin concentration in the range of 10-140 ng ml−1. The limit of detection is 2.71 ng ml−1. Based on this, a new direct quantitative determination method for γ-globulin in blood serum samples without separation of human serum albumin (HSA) is established. The contents of γ-IgG in blood serum samples were determined with recovery of 95.7-102.5% and R.S.D. of 1.6-2.4%. This method is proved to be very sensitive, rapid, simple and tolerance of most interfering substances. 相似文献
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C60-吡咯烷衍生物的合成及非线性光学性质的研究 总被引:1,自引:0,他引:1
通过富勒烯C60与肌氨酸和有机醛化合物的1,3-偶极环加成反应, 获得了九种含不同有机功能基团的C60吡咯烷衍生物1~9, 用1H NMR, 13C NMR, FTIR, UV-vis和FAB-MS进行了结构表征; 利用皮秒激光光源, 采用z扫描技术测定了分子的三阶非线性超极化率γ(3), 结果显示: 化合物3 (γ(3)=4.14×10-33 esu)具有最大的三阶非线性光学系数, 说明增加噻吩共轭链的长度, 使三阶非线性活性增加; 对具有相同共轭链的C60-噻吩吡咯烷衍生物(2, 5, 1和4), 吸电子取代基减小了三阶光学非线性活性, 给电子基增大了三阶光学非线性活性; 同时发现喹啉环2-位键联(7)比4-位(8)有更好的三阶光学非线性活性. 相似文献
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Yu-Xi Sun Ran Zhang De-Jun Ding Shu Liu Bao-Lin Wang Yan-Li Wang Yong-Xiang Lin 《Structural chemistry》2006,17(6):655-665
The Schiff base compounds, 4-(2-hydroxy-5-nitr- obenzylideneamino)-1,2-dihydro-1,5-dimethyl-2-phenylpy- razol-3-one and 4-(3-bromo-5-chloro-2-hydroxybenz-
ylideneamino)-1,2-dihydro-1,5-dimethyl-2-phenylpyrazol-3-one, have been synthesized and characterized by elemental analysis,
IR, and X-ray single crystal determination. Density functional calculations of the structures, natural bond orbitals, and
frontier molecular orbitals and Mülliken charge analysis on the compounds were performed at B3LYP/6-31+G(d) level of theory.
Vibrational frequencies were also predicted, assigned, and compared with the experimental values, which supported each other. 相似文献
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Transition Metal Chemistry - The crystal structures and magnetic properties of three coordination compounds constructed from various nitroxide radicals L and MII(hfac)2(H2O)2 building blocks... 相似文献
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