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Khoroshko LO Takhistov VV Petrova VN Viktorovskii IV Lahtiperä M Paasivirta J 《European journal of mass spectrometry (Chichester, England)》2004,10(5):731-736
Structures of six cyclic polysulfides, previously unknown as organic environmental pollutants, were analyzed from a sediment sample from the Eastern Gulf of Finland. The determinations were done by gas chromatography connected to mass spectrometry. High resolution (HRMS) measurements of the isotopic composition of four compounds could be done to confirm their molecular formulae. Total low resolution (LRMS) spectra were used to elucidate structures of all six compounds by thermochemical approach, application of fragmentation rules and by ICLU simulation of the spectra. The compounds were deduced to be (in the order of GC- retention) 1,2,4-trithiacycloheptane, tetrathiacyclopentane, 1,2,4,5-tetrathia-cyclohexane, 1,2,3,4- tetrathiacycloheptane, 1,2,3,4-tetrathiacyclohexane and 1,2,4,6-tetrathiacyclooctane. 相似文献
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V. A. Mazunov M. V. Muftakhov A. A. Krivoruchko V. V. Takhistov 《Russian Chemical Bulletin》1991,40(3):511-513
Appearance energies have been measured for negative ions formed in the gas phase upon dissociative capture of electrons by molecules of cyclopentadiene, pyrrole, selenophene, thiophene, furan, and furan derivatives. From an analysis of the enthalpies of formation of the fragmentation products, it has been established that electron capture by molecules of C4H4X (X=O, S, Se, NH, CH2) leads to the formation of ions with cyclic and acyclic structures.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 590–592, March, 1991. 相似文献
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I. N. Domnin A. M. Lakshin A. D. Misharev V. V. Takhistov W. A. Knig 《Journal of mass spectrometry : JMS》1985,20(11):674-676
The behaviour of substituted cyclopropenes under electron impact is to a large extent determined by the presence of the unsaturated three-membered ring which is capable of efficient delocalization of the positive charge. The loss of one of the substituents at the C(3) position of the small ring is characteristic for the fragmentation of cyclopropenes; the loss of the substituent which is less electron donating occurs preferentially. The presence of substituents with heteroatoms on the three-membered ring may lead to changes in the fragmentation scheme characteristic for the specific set of substituents. 相似文献