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Chemical Ionization Mass Spectrometry
Advances in biochemical psychopharmacology, 1973The chemical ionization technique relies on the presence of a relatively high pressure in the ion source region. This high pressure promotes various ion molecule reactions which result in a highly sensitive method for ionization of sample molecules via ion molecule reactions. To obtain the high pressures desired in the ion source, one has to design and
E C, Horning +4 more
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Carbohydrate Research, 2010
Glucose, galactose, and mannose in H(2)O and D(2)O were ionized by an atmospheric pressure chemical ionization (APCI) method. Isotope effects on fragmentation patterns of the monosaccharides were examined by deuterium replacement of the -OH groups to distinguish the isomers with a single mass spectrometer. The most abundant ions were the [M+H(2)O](+)()
Sung-Seen, Choi, Jong-Chul, Kim
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Glucose, galactose, and mannose in H(2)O and D(2)O were ionized by an atmospheric pressure chemical ionization (APCI) method. Isotope effects on fragmentation patterns of the monosaccharides were examined by deuterium replacement of the -OH groups to distinguish the isomers with a single mass spectrometer. The most abundant ions were the [M+H(2)O](+)()
Sung-Seen, Choi, Jong-Chul, Kim
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Chemical protection against ionizing radiation
Advances in Space Research, 1989Some of the problems related to chemical protection against ionizing radiation are discussed with emphasis on: definition, classification, degree of protection, mechanisms of action and toxicity. Results on the biological response modifyers (BRMs) and on the combination of nontoxic (i.e. low) doses of sulphydryl radioprotectors and BRMs are presented.
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1979
The ion chemistry which proceeds in natural hydrocarbon flames, in particular CH4/O2 flames, is viewed from the perspective provided by recent room-temperature measurements of individual ion-molecule reactions. Limited reaction schemes are proposed for both positive and negative ions in the preheat region, the reaction zone, and the burnt gas ...
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The ion chemistry which proceeds in natural hydrocarbon flames, in particular CH4/O2 flames, is viewed from the perspective provided by recent room-temperature measurements of individual ion-molecule reactions. Limited reaction schemes are proposed for both positive and negative ions in the preheat region, the reaction zone, and the burnt gas ...
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Metastable ions in chemical ionization
Organic Mass Spectrometry, 1977AbstractThe ion [C3H5]+ generated in a chemical ionization source by a variety of methods, including protonation and charge exchange, exhibits a metastable peak for H2 loss which is two orders of magnitude weaker than that formed in an electron impact source. The stable [C3H5]+ ions generated by electron impact and chemical ionization undergo collision‐
D. Cameron +3 more
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Chemical Reaction and Ionization in Flames
1973Although the concept of a flame is clear to everyone, no completely satisfactory definition has been put forward. A flame results from an exothermic gaseous reaction, but not all such reactions sustain flames. A flame temperature may vary between a few hundred and over five thousand degrees, and the luminosity may be due to the spectra of species ...
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Chemical ionization of fullerenes
The Journal of Physical Chemistry, 1991Stephen W. McElvany, John H. Callahan
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Chemical Ionization Mass Spectrometry.
1980Abstract : Research results presented in this report include new methodology for obtaining mass spectra of thermally labile organics, for generating elemental composition data from low resolution GC/MS mass spectra, for counting protons in organic samples under GC/MS conditions, and for the direct analysis of complex mixtures by triple quadrupole mass ...
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