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101.
Moslem Mansour Lakouraj Mahmood Tajbakhsh Hamed Tashakkorian 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):83-88
Summary. An efficient method for the selective oxidation of sulfides to sulfoxides under mild and environmentally safe conditions is
achieved using hydrogen peroxide in the presence of Amberlyst 15 and Amberlite IR-400 at room temperature. This procedure
can be applied for dialkyl and diaryl sulfides with a variety of functional groups. Functional groups such as hydroxyl, methoxy,
amino, aldehyde, and olefinic double bonds remain intact. 相似文献
102.
103.
Simple and efficient CuI/PEG-400 system for amination of aryl halides with aqueous ammonia 总被引:1,自引:0,他引:1
The cross-coupling reaction between aryl halides with aqueous ammonia was efficiently catalyzed in CuI/PEG-400 System with high yield. A range of electron-withdrawing or electron-donating aryl iodides and bromides were found to be applicable to the environmentally benign system. The process allows assembly of primary arylamines in great diversity which bear a wide range of functional groups including cyano, nitro, acetyl, ether, or amino moiety. 相似文献
104.
Nucleophilic species of tellurium and sulfur were generated in situ from the reaction of the respective diorganyl dichalcogenides with NaBH4 in PEG-400 as solvent and selectively added to electron-deficient alkenes. Chalcogenolate anions were directly added at mild conditions by this simple procedure and in all cases furnished the respective Michael adducts in short reaction times and good yields. 相似文献
105.
106.
稀土有机配合物进行无机化能提高热稳定性,但无机化基质对稀土有机配合物的荧光性影响较大,采用PEG3400对复合体进行改性,有利于改善荧光性.文章采用溶胶-凝胶法合成Eu(BA)3/SiO2和Eu(BA)3/PEG400-SiO2复合发光材料.研究了PEG400掺入量对SiO2中Eu(BA)3发光性能的影响,PEG400作为路易斯硬酸和稀土离子配体增强了Eu(BA)3的发光性能.用红外光谱说明PEG400的掺人有利于减少发光材料中的结晶水和羟基数目.通过原子力显微镜分析了PEG400的掺入量对SiO2基质结构的影响. 相似文献
107.
《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):831-835
e
+
e
- production was studied using the High Acceptance DiElectron Spectrometer (HADES). In pp collisions at 2.2GeV kinetic beam energy, the exclusive η production and the Dalitz decay η→γe
+
e
- have been reconstructed. The electromagnetic form factor of the latter decay was found to be in good agreement with the existing
theoretical predictions. In addition, an inclusive e
+
e
- invariant-mass spectrum from the 12C + 12C reaction at 2AGeV is presented and compared with a simplified thermal model. 相似文献
108.
Stress corrosion of silicate glass: a review 总被引:1,自引:0,他引:1
René Gy 《Journal of Non》2003,316(1):1-11
In the first section of the present paper, some examples, from the field, of the manifestations or consequences of the fatigue of silicate glass are briefly presented. In the second section, the interpretation of fatigue in terms of stress corrosion is reviewed: the role of ambient molecular water is well established. Whatever the details of the mechanism of action of water, it takes place very efficiently in the highly strained material close to the tip of a surface crack. This enables its sub-critical growth to be explained. But it does not explain many other observed effects of the environment on the mechanical behavior of silicate glass, and, in the last section, questions and issues are presented, which would still need to be investigated. 相似文献
109.
流动注射化学发光法对安乃近进行选择性定量测定 总被引:5,自引:0,他引:5
通过对药物中安乃近的选择性定量测定 ,提出一种新的化学发光分析法。当安乃近溶液与酸性的聚乙二醇 4 0 0及罗丹明 6G混合溶液相遇时 ,会产生强烈的化学发光信号 ,根据光信号的大小即可定量测定安乃近的含量。反应中无任何氧化剂使用 ,因此 ,很难解释光信号产生的原因 ,该反应发光机理仍在探讨之中。这种测定方法具有极高的选择性 ,无论被测物是否含有磺酸基团 ,实验中未发现任何其他药物或化学物质会产生有意义的光信号 ,所以 ,不会象其他化学发光体系存在其他物质干扰问题。另外 ,此反应具有高度的灵敏性 ,其工作曲线线性范围为 0 0 1~ 1 0 0 μg·mL-1 ,检出限为 0 0 0 3μg·mL-1 ,此为目前安乃近的所有化学发光测定法中最低的检出限值。该测定方法已成功用于针剂及片剂药物中乃安近的定量测定 相似文献
110.