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161.
Absolute configuration of miyakosyne A at its isolated branched methyl stereogenic center has been studied by chemical degradation in combination with esterification with the Ohrui's acid. Comparison of the 1H NMR data of the relevant diesters for the degradation product and the synthetic standards indicated the 14R-configuration. 相似文献
162.
乙炔分子振动光谱的相互作用模式计算 总被引:1,自引:0,他引:1
应用量子自陷理论,发展了分子振动光变的相互作用模式方法,对C2H2与C2D2分子振动光谱进行了计算。计算结果与观测值很符合。 相似文献
163.
164.
M. Herman 《Molecular physics》2013,111(17-18):2217-2241
The evolution of high-resolution spectroscopic investigation of the vibration–rotation energy states of acetylene in its ground electronic state is presented, focusing on advances co-authored by the ULB group. The emergence of a global picture accounting for all available spectroscopic fingerprints, at their full accuracy, is highlighted. The contributions of this research to various topics is illustrated, including instrumental developments, local mode trends, quantum vs. classical correspondence, energy vs. time approaches and nucleation processes. 相似文献
165.
166.
Reaction ergodography for the addition of lithium hydride to acetylene indicates that the lithium hydride, in both monomeric and dimeric forms, reacts with the acetylene via two similar and competitive pathways. Hence, we have obtained the pseudo-first-order rate constant of this reaction. 相似文献
167.
A series of pyridines substituted in the 2-position were synthesized by cobalt(I)-catalyzed cotrimerization of alkynes and nitriles. The reactions are usually enhanced by light. The reaction conditions are very mild. Activity and selectivity are satisfactory with respect to formation of pyridines, but depend on the type of nitrile. 相似文献
168.
169.
We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102 nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (13C2H2) and hydrogen cyanide (H13C14N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode. 相似文献
170.
J.L. Hardwick Z.T. Martin M.J. Pilkenton E.N. Wolf 《Journal of Molecular Spectroscopy》2007,243(1):10-15
The absorption spectra of H12C13CD and H13C12CD have been observed at high resolution between 6480 and 6610 cm−1 using an external cavity diode laser. The strong 2ν1 band has been observed for each species using a sample enriched in deuterium at natural abundance of 13C. Rotational analyses reveal bands of both species to be essentially unperturbed. Centers of unblended lines are determined with an accuracy of approximately 10 MHz. 相似文献