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991.
Preparation and Characterization of Three-dimensionally Ordered Crystalline Macroporous CeO2 总被引:2,自引:0,他引:2
Xi Yan ZHANG Tong Wen WANG Wen Qing JIANG Di WU Ling LIU Ai Hong DUAN 《中国化学快报》2005,16(8):1109-1112
Three-dimensional ordered macroporous (3DOM) materials are of great potential importance in catalysis, selective separation, sensor arrays and communications with optical band gaps1. Many results in the synthesis of 3DOM materials have been reported, such as closed-packed silica spheres or polystyrenes (PS) templating routes for silica2, metal oxides1-6 and metals7. Recently, poly(methyl methacrylate) (PMMA) colloidal crystal templates have been used to prepare 3DOM materials of metals8,… 相似文献
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Tetragonal tungsten bronze K0.71Nd0.028WO3 was synthesized by rare earth co-permeation method using Keggin type POMs of α-K10[SiCu3(OH2)W9O37]·6H2O (abbreviated as SiW9Cu3) as precursor. XRD, XPS, XRF, TG-DTA were used to characterize the resulting material. The XPS results indicate that Nd has permeated and diffused into the body of the sample and exists in tungsten bronze in the form of K0.71Nd0.028WO3. The results of TG-DTA show that K0.71Nd0.028WO3 begins to decompose at 320 ℃. The consequence of DC four-probe shows that the conductivity of the sample permeated by rare earth is 103 times higher than that of the sample only permeated by methanol at room temperature. The conductivity of the sample only permeated by methanol is only 10-3 S·cm-1 but the conductivity of the sample permeated by rare earth is 1.65 S·cm-1. 相似文献
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建立了同时测定头发中10种蛋白同化激素液相色谱-串联质谱(LC/MS/MS)分析方法。头发样品经NaOH消解、戊烷液液提取后,用反相液相色谱分离,电喷雾正离子源进行离子化,用多反应监测方式(MRM)对这10种蛋白同化激素的母离子及子离子进行监测,三重四极杆质谱测定。10种蛋白同化激素的检出限为1~20ng/g;相对标准偏差(RSD)为1.72%~13.77%;回收率为38.20%~110.38%;线性回归系数(R2)为0.9958~0.9999。本方法简便快速、灵敏度高、专属性强,可满足在兴奋剂检测或毒物分析中对毛发中蛋白同化激素测定的要求。 相似文献
998.
Yan Ping Wang Wen Fa Xie Bin Li Wen Lian Li 《中国化学快报》2007,18(12):1501-1504
A new 1,3,4-oxadiazole-contanining rhenium(I) complex,with the formula [Re(CO)_3(Bphen)(PTOP)],(Bphen=bathophe- nardine,PTOP=4-(5-p-tolyl-1,3,4-oxadiazd-2-yl)pyridine),is synthesized and characterized by elemental analysis,IR,~1H NMR, UV-vis and luminescence spectroscopy.The double-layer electroluminescence devices based on the Re(I) complex have been fabricated by spin-coating technique.The turn-on voltage,maximum efficiency,and brightness for green emission obtained from the devices are 9V,2.1cd/A and 165cd/m~2,respectively. 相似文献
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The electrochemical behavior and the interaction of alizarin red S (ARS) with calf thymus DNA was investigated on a bare glassy carbon electrode (GCE) and DNA modified GCE (DNA/GCE), respectively. ARS showed a pair of redox peaks at ?0.445 V and ?0.414 V on a bare GCE. On addition of DNA into the ARS solution, the peak current of ARS decreased and the peak potential positively shifted, but without new redox peaks appeared. The ARS reduction peak current increased with immersion time on a DNA/GCE. The results showed that ARS could interact with DNA molecules by intercalative binding mode. The equilibrium constant, binding number and the ratio of binding constant for oxidized and reduced ARS forms were obtained. The DNA damage was directly detected by appearance of guanosine and adenosine bases oxidation signal. The influence of experimental conditions on DNA damage extent was discussed in detail. 相似文献
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