Stereoisomerism and thermodynamic properties of propyl ethers in the ideal gas state

© 2019 Elsevier Ltd The intramolecular rotation of several C–O and C–C bonds of a set of aliphatic ethers were studied using quantum-chemical calculations at the RB3LYP 6-311++G(3df,3pd) level of theory. For molecules of di-n-propyl (I), diisopropyl (II), methyl-n-propyl (III) and methyl isopropyl (IV) ether, the most stable conformations were found, geometric parameters and rotational constants were optimized, relative energies were estimated, and fundamental vibrations were simulated for each of them. The rotational (conformational) isomerism of these flexible aliphatic ethers with carbon and oxygen atoms in an sp3 hybridized state are examined. Thermodynamic functions for di-n-propyl (I), diisopropyl (II), methyl-n-propyl (III) and methyl isopropyl (IV) ethers in the ideal gas state in the temperature range T = (50–1500 K) were calculated for the first time using molecular and spectral data

Stereoisomerism and thermodynamic properties of propyl ethers in the ideal gas state

© 2019 Elsevier Ltd The intramolecular rotation of several C–O and C–C bonds of a set of aliphatic ethers were studied using quantum-chemical calculations at the RB3LYP 6-311++G(3df,3pd) level of theory. For molecules of di-n-propyl (I), diisopropyl (II), methyl-n-propyl (III) and methyl isopropyl (IV) ether, the most stable conformations were found, geometric parameters and rotational constants were optimized, relative energies were estimated, and fundamental vibrations were simulated for each of them. The rotational (conformational) isomerism of these flexible aliphatic ethers with carbon and oxygen atoms in an sp3 hybridized state are examined. Thermodynamic functions for di-n-propyl (I), diisopropyl (II), methyl-n-propyl (III) and methyl isopropyl (IV) ethers in the ideal gas state in the temperature range T = (50–1500 K) were calculated for the first time using molecular and spectral data

Mathematic modeling and calculation of force parameters at simultaneous insertion of two absolutely rigid wedges of various heights and vertex angles

Математическое моделирование и расчет силовых параметров при совместном внедрении двух абсолютно жестких клиньев различных высот и углов при вершине / В. Ф. Потапкин [и др.] // Захист металургійних машин від поломок: зб. наук. пр. / ПДТУ. - Маріуполь, 2000. - Вип. 5. - С. 209-216.Рассмотренную методику и программные средства, разработанные на её основе, можно использовать для расчета процесса накатки рабочей поверхности прокатных валков, для прогнозирования шероховатости прокатываемой полосы, расчета процесса прокатки сложных профилей и т.д.Розглянуту методику і програмні засоби, розроблені на її основі, можна використовувати для розрахунку процесу накатування робочої поверхні прокатних валків, для прогнозування шорсткості прокатуваної штаби, розрахунку процесу прокатування складних профілів тощо.The considered practice and software developed based on it can be used for calculation of the process of work-hardening of the mill roll working surface, for forecasting of roughness of the rolled strip, calculation of rolling of complicated profiles, etc