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191.
Synthesis of mevalonolactone (hiochic acid lactone) employing asymmetric epoxidation as the key-step
(R)( — )-Mevalonolactone (hiochic acid lactone)of 91–93%e.e. was synthesized from an achiral starting material employing the Sharpless asymmetric epoxidation as the key-step. 相似文献
192.
The IR spectra of cyclobutanecarbonyl chloride and bromide and their α-deuterated compounds have been recorded in the vapor, liquid and crystal states. The Raman spectra have also been measured in the liquid state. Comparison of the spectra in the liquid phase with those in the crystal phase reveals that these acyl halides exist in a conformational equilibrium in the liquid state. Tentative vibrational assignments are proposed on the basis of the isotope effect and previous published results for other simple cyclobutane compounds. 相似文献
193.
A general formalism is given for treating vibrational mode mixing, frequency shifts, and atomic equilibrium position shifts under electronic excitation in resonance Raman scattering. The theory is exact for first-order scattering at T = 0 K for all linear and quadratic electron-phonon coupling strengths. Numerical results illustrating mode mixing are presented. 相似文献
194.
The infrared and Raman spectra of solid state samples of pyromellitic dianhydride have been measured. The infrared—Raman mutual exclusion rule has been observed and the frequencies have been tentatively assigned on the basis of D2h symmetry. The values of the CO and skeletal ring stretching frequencies have been interpreted in terms of a conjugated π-system. 相似文献
195.
Multiconfigurational many-body perturbation theory is applied to the problem of calculating ionization potentials, electron affinities, and excitation energies. H2O, C2H4, and H2 are studied, with correlation corrections through third order and inclusive of certain higher-order terms. Results are compared with those by other many-body theoretical methods. 相似文献
196.
Toshiaki Munakata Koichi Ohno Yoshiya Harada Kozo Kuchitsu 《Chemical physics letters》1981,83(2):243-245
The Ne1(3P2) Penning electron spectra and the Ne I photoelectron spectra were measured in the gas phase. The observed systematic differences in their relative intensities were interpreted in terms of the electron distributions of the relevant molecular orbitals and used for assignment of the deep π bands, π1 (12.4 eV) for naphthalene, and π2 (11.9 eV) and π1 (12.8 eV) for anthracene. 相似文献
197.
A photolysis of di-t-butyl peroxide (BOOB) was studied by using a thermal lensing technique. This technique is found to be applicable to the determination Of the rate Constants of the decay of t-butoxy radical (BO ) and the hydrogen abstraction reaction. 相似文献
198.
目前在亚太地区,特别重视RFID应用的国家和地区有美国、日本、中国、新加坡、中国台湾和中国香港等。本文在研究、分析美国、日本和中国在应用RFID的不同特点的基础上,得出中国在RFID的应用上应该侧重于哪些方面的结论。 相似文献
199.
Sumio Sakka 《Journal of Sol-Gel Science and Technology》2006,37(2):135-140
In Japan, sol-gel research activities are very prosperous and there are many successful commercial products. It appears that
this trend will continue into the future. In this article, basic sol-gel research carried out in Japanese universities and
applications of the sol-gel method to industrial production will be described. It should be noted that many unique studies,
including photocatalysts and products involving coatings applied to automobiles and display panels, are found in Japan. 相似文献
200.