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1.
Arthur G. Maki John C. Grecu Brenda Winnewisser Manfred Winnewisser 《Journal of Molecular Spectroscopy》2003,222(2):198-212
High-resolution spectra of 15N12C12C15N and 14N13C13C14N have been measured and analyzed from 200 to 3600 cm−1. All the vibrational levels below 900 cm−1 have been observed and characterized. The Fermi resonance between ν2 and 2ν4 has been studied and the resonance constant has been determined for several cases. Several Σ− states have been directly observed for the first time for each isotopomer, the (0001111)0f, (0011111)0f, and (0002222)0f states. The pattern of the energy levels for clusters of l-type resonance coupled levels, such as 0001131,3, has been determined for cyanogen for the first time. Among other things this involved the determination of the vibrational l-type resonance constant, r45. Many of the power series constants, αi and xij, and higher order constants have been determined. 相似文献
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M~++BrCN─→MCN~++Br气相反应的从头算研究朱荣顺,戴树珊(云南大学化学系,昆明,650091)关键词气相反应,过渡金属阳离子,溴化氰,从头算,相对论赝势对过渡金属离子与一些小分子的气相反应已有大量的实验和理论研究[1~5],MichelS... 相似文献
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1,2,4-三嗪类化合物的研究(ⅩⅫ)──咪唑并-(5,4-e)-1,2,4-三嗪衍生物的合成沙耀武,蔡孟深(北京医科大学药学院,北京,100083)关键词乙二脒腙,原甲酸三乙酯,1,2,4-三嗪,咪唑并-(5,4-e)-1,2,4-三嗪天然碱基拮抗... 相似文献
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双金属催化剂是一类重要的多相催化剂。其中d电子在催化活性方面起着重要的作用.本文在Co_3[Fe(CN)_6]_2的工作基础上,进一步研究了该配合物在硅胶、氧化铝、以及氧化镁上的热性质,同时考察了CN~-在Co-Fe体系双端基配位的活化加氢,探讨了载体的影响. 相似文献
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Arthur G. Maki 《Journal of Molecular Spectroscopy》2011,269(2):166-174
The high-resolution spectrum of cyanogen (14N12C12C14N) has been measured from 500 to 4900 cm−1. For this isotopomer many combination levels with both degenerate fundamentals, ν4 and ν5, have been measured for the first time and the effects of vibrational l-type resonance are observed as well as rotational l-type resonance. The effects of the vibrational resonance coupling ν2 and 2ν4 have also been studied. The data have been combined with earlier measurements below 500 cm−1 to give a comprehensive catalog of the vibrational energy levels and the rovibrational constants for the normal isotopomer of cyanogen. A comparison of the term value constants for the three major symmetric isotopomers is given and they are compared with a recent ab initio calculation. The present data were combined with earlier work on the two symmetric isotopomers, 13C214N2 and 12C215N2, to obtain the equilibrium bond lengths, rCC = 138.109(60) pm and rCN = 115.976(40) pm. 相似文献
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Regioselective One‐pot Synthesis of New Unsymmetric Spiro Dihydrofurans in the Reaction of Mixed Two Different Cyclic β‐Dicarbonyl Compounds with BrCN and Aldehydes in the Presence of Et3N 下载免费PDF全文
Crossed one‐pot reaction of mixed cyclic β‐dicarbonyl with various aldehydes in the presence of cyano gen bromide and triethylamine leads to the selective and efficient formation of crossed new unsymmetri cal spiro dihydrofurans at room temperature. The products were obtained in good to excellent yields. Structure elucidation was carried out by 1H NMR, 13C NMR, FT‐IR spectroscopy, Mass analyses and X‐ray crystallography technique. A proposed mechanism was discussed for the formation of products. 相似文献
7.
Morla A Poirier F Pons S Beaulieu C Charrier JP Ataman-Onal Y Gléhen O Jolivet M Choquet-Kastylevsky G 《Electrophoresis》2008,29(20):4158-4168
Proteomic approaches including high-resolution 2-DE are providing the tools needed to discover disease-associated biomarkers in complex biological samples. Although 2-DE is an extremely powerful approach to analyze the proteome, the separation of proteins with extreme molecular masses still remains an issue requiring improvement. Because high molecular mass (HMM) proteins larger than 150 kDa have already been observed to be differentially expressed in several pathologies such as cancer, we developed an original strategy to analyze this part of the proteome that is not easily separated by 2-DE in polyacrylamide gels. This strategy is based on the 2-DE separation of cyanogen bromide (CNBr) fragments of purified HMM protein fractions, and combines techniques including SEC fractionation, TCA precipitation, CNBr cleavage, 2-DE and MS analysis. The method was first tested on a model protein, the BSA. Preliminary results obtained using colonic tissues led to the identification of six HMM proteins with M(r) comprised between 163 and 533 kDa in their reduced state. These results demonstrated that our CNBr/2-DE approach should provide a powerful tool for identification of new biomarkers larger than 150 kDa. 相似文献
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Summary The response of a flame ionisation detector (FID) to cyanogen ((CN)2) and cyanogen chloride (CNCI) has been studied. The lower limits of detection for (CN)2 and CNCl were 6×10−12 moles and 2×10−11 moles respectively. In a comparative study a thermal conductivity detector gave as its lower limit of detection for both
(CN)2 and CNCl 4×10−11 moles. Both detectors showed excellent linearity over the range 0 to 10 micromoles. The ratio of the gradients of the FID
calibrations (CN)2/CNCI were found to be approximately two suggesting the response depended on the cyanide group.
The response and stability of the FID was investigated as a function of air and hydrogen flow-rates. The response increased
with increasing air flow-rate for both (CN)2 and CNCI up to 300cm3min−1, thereafter no significant increase was observed.
On raising the hydrogen flow from 10 to 25cm3min−1 only a slight increase in the sensitivity of the FID towards both (CN)2 and CNCI was observed. At higher flow rates the response for (CN)2 increased markedly whereas at the same flow rates the response for CNCI increased only slightly. 相似文献