3,643 research outputs found
Modeling termination kinetics of non-stationary free-radical polymerizations
No full textPulsed-laser induced polymerization is modeled via an approach presented in a previous paper. An equation for the time dependence of free-radical concentration is derived. It is shown that the termination rate coefficient may vary significantly as a function of time after applying the laser pulse despite of the fact that the change in monomer concentration during one experiment is negligible. For the limiting case of t ≫ c-1 (kpM)-1, where c is a dimensionless chain-transfer constant, kp the propagation rate coefficient and M the monomer concentration, an analytical expression for kt is derived. It is also shown that time-resolved single pulsed-laser polymerization (SP-PLP) experiments can yield the parameters that allow the modeling of kt in quasi-stationary polymerization. The influence of inhibitors is also considered. The conditions are analyzed under which M (t) curves recorded at different extents of laser-induced photo-initiator decomposition intersect. It is shown that such type of behavior is associated with chain-length dependence of kt
The J-Band of J-Aggregates as the Egorov Nano-Resonance
No full textThe well-known narrow and intense optical absorption J-band was discovered experimentally by Jelley and independently Scheibe in 1936. In 1938, Franck and Teller, associating the appearance of the J-band with the formation of molecular J-aggregates, gave a theoretical explanation for the J-band based on the Frenkel exciton model. This explanation has been developed in detail over a long period of time by many authors, including the author of this paper. The main shortcoming of all those explanations is the inability to explain the shape of the dye monomer bands from which J-aggregates are formed. In this mini-review, the author gives an explanation of the J-band as the so-called Egorov nano-resonance discovered in a new theory, quantum–classical mechanics, which includes an explanation of the shape of monomer bands
Dominated Convergence and Egorov Theorems for Filter Convergen
No full textWe study the filters, such that for convergence with respect to this filters the Lebesgue dominated convergence theorem and the Egorov theorem on almost uniform convergence are valid (the Lebesgue filters and the Egorov filters, respectively). Some characterizations of the Egorov and the Lebesgue filters are given. It is shown that the class of Egorov filters is a proper subset of the class of Lebesgue filters, in particular, statistical convergence filter is the Lebesgue but not the Egorov filter. It is also shown that there are no free Lebesgue ultrafilters. Significant attention is paid to the filters generated by a matrix summability method
Unknown pages of cardiovascular surgery history in Sakhalin Region (Surgeon Alfred Egorov)
No full textThe article is dedicated to the history of cardiac surgery in the Sakhalin Region, which over a 20-year period of its development has achieved much success and is now mastering open heart surgery, and to Sakhalin Chief Surgeon Alfred Egorov (1926–1996). Doctor A. Egorov was a great healthcare manager and a surgeon, Honorary Physician of Russian Federation, Member of the USSR and Russian Federation Surgical Society, who over a period of 1964–1986 made a major contribution to the development of anesthesia and surgical care in Sakhalin Region, while strengthening the material and technical facilities of regional medical institutions. The emphasis in the article is placed on Doctor A. Egorov’s role in the development of cardiovascular surgery and on the support that Novosibirsk Institute of Circulation Pathology (now Evgeny Meshalkin National Medical Research Center) has given in this process. As early as 1966 he introduced new methods of cardiac diagnostics and performed pioneer heart operations. His invention, a dilator of heart stenosed orifices (valvulotome), came into common use in heart surgery. It was A. Egorov who performed the first open heart surgery (February 1969) in the Far Eastern Region of Russian Federation.Received 21 May 2018. Revised 2 July 2018. Accepted 3 July 2018.Funding: The study did not have sponsorship.Conflict of interest: Author declares no conflict of interest.AcknowledgmentThe author expresses the gratitude to Oleg S. Egorov, Alfred V. Egorov’s grandson for access to the photos from their family archive.</p
A. N. Egorov. Slaviano-Germanskia otnochenia v srednic vieka. Kolonizatsia Meklenburga v XIII v. (Germains et Slaves au moyen âge. La colonisation du Mecklenbourg au XIIIe siècle)
No full textLéger Louis. A. N. Egorov. Slaviano-Germanskia otnochenia v srednic vieka. Kolonizatsia Meklenburga v XIII v. (Germains et Slaves au moyen âge. La colonisation du Mecklenbourg au XIIIe siècle). In: Journal des savants. 14ᵉ année, Juillet 1916. pp. 332-333
Modeling the effects of primary radicals in free-radical polymerization
No full textThe effects of non-ideal initiator decomposition, i.e., decomposition into two primary radicals of different reactivity toward the monomer, and of primary radical termination, on the kinetics of steady-state free-radical polymerization are considered. Analytical expressions for the exponent n in the power-law dependence of polymerization rate on initiation rate are derived for these two situations. Theory predicts that n should be below the classical value of 1/2. In the case of non-ideal initiator decomposition, n decreases with the size of the dimensionless parameter alpha drop (k(tz)/k(dz))rootr(in)/k(t), where k(tz) is the termination rate coefficient for the reaction of a non-propagating primary radical with a macroradical, k(dz) is the first-order decomposition rate coefficient of non-propagating (passive) radicals, r(in) is initiation rate, and k(t) is the termination rate coefficient of two active radicals. In the case of primary radical termination, n decreases with the M 1/2 size of the dimensionless parameter beta drop k(l,s) r(in)(1/2)/k(p,s)Mk(t,l)(1/2), where k(t,s) is the termination rate coeificients for the reaction of a primary ("shorf") radical with a macroradical, k(t,l) is the termination rate coefficients of two large radicals, k(p,s) is the propagation rate coefficient of primary radicals and M is monomer concentration. As k(t) is deduced from coupled parameters such as k(l)/k(p), the dependence of k(p) on chain length is also briefly discussed. This dependence is particularly pronounced at small chain lengths. Moreover, effects of chain transfer to monomer on n are discussed
A. N. Egorov. Slaviano-Germanskia otnochenia v srednic vieka. Kolonizatsia Meklenburga v XIII v. (Germains et Slaves au moyen âge. La colonisation du Mecklenbourg au XIIIe siècle)
No full textLéger Louis. A. N. Egorov. Slaviano-Germanskia otnochenia v srednic vieka. Kolonizatsia Meklenburga v XIII v. (Germains et Slaves au moyen âge. La colonisation du Mecklenbourg au XIIIe siècle). In: Journal des savants. 14ᵉ année, Juillet 1916. pp. 332-333
Quantum-classical mechanics: On the problem of a two-photon resonance band shape in polymethine dyes +
No full textDependence of the model two-photon band on the energy of nuclear reorganization.
Dependence of the model two-photon band on the concentration of the dye in the solution and on the temperature
Dozy-Chaos Mechanics for a Broad Audience
No full textA new and universal theoretical approach to the dynamics of the transient state in elementary physico-chemical processes, called dozy-chaos mechanics (Egorov, V.V. Heliyon Physics2019, 5, e02579), is introduced to a wide general readership
Chemical composition of Helichrysum arenarium and Helichrysum nogaicum essential oils, growing in the Astrakhan region
No full textPlants of Helichrysum genus belong to Asteraceae family and abound with species. The’re two species of plants of Helichrysum genus in the Astrakhan region – Helichrysum arenarium Moench and Hеlichrisum nogaicum Zvelev that was discovered later and isn’t studied well enough yet. Helichrysum arenarium is a well-known medical plant widely used in both academic and traditional medicine and included into the State Pharmacopoeia. Inflorescences of Helichrysum arenarium produce cholagogic, hemostatic, detoxicating, laxative, anti-inflammatory and diuretic effects, which is due to content of flavonoids, terpenoids and other components. This works shows results of studies of chemical composition of extracted essential oils of Hеlichrisum nogaicum and Helichrysum arenarium growing in the Astrakhan Region. Samples of essential oils of plants under studies have been obtained by steam distillation. Optimal steam distillation process duration has been determined by experiment taking studies of dynamics of essential oil yield change through time as a ground. Quantitative analysis of main components of Helichrysum arenarium and Hеlichrisum nogaicum essential oils has been carried out by gas-liquid chromatography. It has been identified that Helichrysum arenarium essential oil contains 21 substances. Its main components are camphor (14.59%) and carboxylic acids (37.02%), and 1,8-cineole (5.97%). The main components of the oil Helichrisum nogaicum are camphor (38.33%), borneol (14.21%), cineol-1.8 (11.37%) and terpene-4-ol (5.18%), sesquiterpene compounds (6.28%), and the content of carboxylic acids is insignificant and amounts to 6.58%
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