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91.
Feng X Lu JY Hao Y Banic C Schroeder WH 《Analytical and bioanalytical chemistry》2003,376(7):1137-1140
In this study, a diffusion-type device for generating gaseous mercuric chloride (HgCl2) was systematically evaluated and applied to validate the annular denuder method for sampling gaseous HgCl2 species in a synthetic gas stream. The results show that it takes at least 48 h for the system to reach a steady-state condition after the diffusion cell reaches the temperature set-point and the carrier gas is activated. The primary Hg species from the source was proven to be HgCl2. In the temperature range from –5.00 to 11.80 °C, the Hg emission rates from the source vary from 1.8 to 14.2 pg min–1. It is shown that, under the experimental conditions examined, KCl-coated annular quartz denuders designed for ambient reactive gaseous mercury (RGM) collection could quantitatively collect HgCl2. It is also demonstrated that the impactors used to remove coarse airborne particulate matter could lead to a loss of up to one third of the HgCl2 in the gas stream. 相似文献
92.
采用Monte Carlo方法模拟了HgI2、非晶Se和CdTe几种直接X射线转换探测器在医用X射线范围(10—100keV)的透过谱、背向散射谱、吸收效率和光电灵敏度. 对X射线和HgI2的作用过程模拟采用了EGSnrc Monte Carlo代码系统, 对信号电荷的产生考虑了电荷产生的高斯噪声和材料深陷阱作用造成的部分电荷收集影响. 结果表明, 载流子平均自由程(Schubweg)在相对于探测材料厚度较小时, 陷阱作用能很大地影响探测灵敏度. HgI2的灵敏度是非晶Se的5倍以上, CdTe的灵敏度是非晶Se的10倍以上, 采用高Z序数材料可以大大提高探测灵敏度. 相似文献
93.
N‐sulfonylimines (1) were induced by samarium(II) iodide to produce radical anion intermediates (2) in situ, which were trapped by aliphatic ketones (4) to afford heterocoupling products β‐sulfonamido alcohols (5) in moderate to good yields under mild and neutral conditions. 相似文献
94.
Ryanodine is a potent calcium channel modulator. In this Letter, we report the 10-step synthesis of the highly substituted tricyclic ring system of ryanodine. Diels-Alder reaction via dearomatization of 2,5-dimethylbenzene-1,4-diol and subsequent SmI2-mediated reductive coupling of eight-membered 1,5-diketone efficiently introduced the four consecutive fully substituted carbons of the tricyclo[3.3.2.02,6]decane system. 相似文献
95.
Jing Han Jin Mao Chen Xiao Wen Zhou Yuan Lin Jing Bo Zhang Jian Guang Jia 《中国化学快报》2008,19(8):1004-1007
The screen-printed nanoporous TiO2 thin film was employed to fabricate dye-sensitized solid-state solar cells using CuI as hole-transport materials. The solar cell based on nanoporous TiO2 thin film with large pores formed by the addition of polystyrene balls with diameter of 200 nm to the TiO2 paste exhibits photovoltaic performance enhancement, which is attributed to the good contact of CuI with surface of dye-sensitized thin film due to easy penetration of CuI in the film with large pores. 相似文献
96.
Zhi Chao Wang Lai Jun Wang Ping Zhang Song Zhe Chen Jing Ming Xu Jing Chen 《中国化学快报》2009,20(1):102-105
Three kinds of Pt/alumina catalysts were prepared by impregnation-hydrogen reduction,impregnation-hydrazine reduction and electroless plating methods.Their differences in the structures,specific areas and particle sizes were characterized by XRD,BET and TEM,respectively.Furthermore,their catalytic activities for the hydrogen iodide(HI)decomposition were evaluated in a fixed bed reactor.The results show that the catalyst 5%Pt/Al_2O_3 prepared by the electroless plating has the optimum catalytic properties... 相似文献
97.
Conductance data are reported for NaI, KI, RbI, CsI, NH4I, NaClO4, and KClO4 in propylene carbonate at 25°C in the concentration range 1×10–4 –8.3×10–3M. Analysis of the data with the current conductance theories indicates negligible ion-association, strong cation-solvent and weak anion-solvent interactions. 相似文献
98.
An efficient experimentally simple and inexpensive catalyst system for the selective amidation of aryl iodides using 15 mol% of CuI as catalyst, 15 mol% of L-proline as ligand and KF/Al2O3 as a base in toluene is described. 相似文献
99.
Zhaopeng Xu Lei Zhang Wenxiu Zhang Liangliang Ji 《Crystal Research and Technology》2016,51(1):110-114
According to the thermodynamics analysis, the molar enthalpy change, the molar entropy increase, the Gibbs free energy change and the balance constant of indium iodide polycrystal synthesis reaction were calculated in order to evaluate the feasibility of reaction temperature on 653 K. After the temperature 653 K was applied in the synthesis experiment, indium iodide polycrystal was successfully obtained by the two‐zone vapor transporting method. The result of X‐ray diffraction analysis indicates the temperature 653K can be used for indium iodide polycrystal synthesis. 相似文献
100.
《Tetrahedron letters》2017,58(30):2936-2939
An efficient route for the synthesis of unsymmetrical biaryls was developed via palladium catalyzed reaction of arenediazonium salts and aryl sulfinates under inert atmosphere. This synthesis involves cascade processes. Tetrabutylammonium iodide was used as an iodide source for in situ formation of aryl iodide, followed by desulfinylative cross-coupling reaction between aryl sulfinates and aryl iodides. A wide range of biaryls were selectively prepared in one pot from simple substrates in good to excellent yields. 相似文献