Nitrogen-15 isotope-modified compounds are widely used in medicine, pharmacology, agriculture and various fields of science and their nomenclature is gradually increasing. Their widespread use depends on the availabil...Nitrogen-15 isotope-modified compounds are widely used in medicine, pharmacology, agriculture and various fields of science and their nomenclature is gradually increasing. Their widespread use depends on the availability of inexpensive and simple isotope analysis methods. The present article is an attempt to determine the nitrogen-15 isotope content directly in organic compounds without their conversion. The general principle of possibility of determination of the isotopes of nitrogen directly in organic compounds is proposed. Based on the study of mass-spectra of Carbamide Carbonyldiamide, isocyanic acid and nitrobenzene the mass peaks are selected, by which it is possible to determine the atomic fraction of the isotopes of nitrogen. The respective formulas are proposed.展开更多
The possibility of determining atomic fractions of the isotopes of carbon directly in urea, nitrobenzene, benzophenone, benzoic acid and 2-Hydroxybenzoic acid in compounds isotopically modified by all carbon centers, ...The possibility of determining atomic fractions of the isotopes of carbon directly in urea, nitrobenzene, benzophenone, benzoic acid and 2-Hydroxybenzoic acid in compounds isotopically modified by all carbon centers, as well as by one or several identical carbon centers is considered. The mass peaks of the mass spectrum that allows determining the atomic fraction of carbon isotopes are selected. The respective formulas are proposed. Until now, isotope analysis of these compounds has been carried out by converting them to carbon monoxide or dioxide, and it has been impossible to determine the atomic fraction of carbon at individual centers.展开更多
文摘Nitrogen-15 isotope-modified compounds are widely used in medicine, pharmacology, agriculture and various fields of science and their nomenclature is gradually increasing. Their widespread use depends on the availability of inexpensive and simple isotope analysis methods. The present article is an attempt to determine the nitrogen-15 isotope content directly in organic compounds without their conversion. The general principle of possibility of determination of the isotopes of nitrogen directly in organic compounds is proposed. Based on the study of mass-spectra of Carbamide Carbonyldiamide, isocyanic acid and nitrobenzene the mass peaks are selected, by which it is possible to determine the atomic fraction of the isotopes of nitrogen. The respective formulas are proposed.
文摘The possibility of determining atomic fractions of the isotopes of carbon directly in urea, nitrobenzene, benzophenone, benzoic acid and 2-Hydroxybenzoic acid in compounds isotopically modified by all carbon centers, as well as by one or several identical carbon centers is considered. The mass peaks of the mass spectrum that allows determining the atomic fraction of carbon isotopes are selected. The respective formulas are proposed. Until now, isotope analysis of these compounds has been carried out by converting them to carbon monoxide or dioxide, and it has been impossible to determine the atomic fraction of carbon at individual centers.