High sensitivity Cavity Ring Down spectroscopy of 18O enriched carbon dioxide between 5850 and 7000 cm-1: Part III-Analysis and theoretical modeling of the 12C17O2, 16O12C17O, 17O12C18O, 16O13C17O and 17O13C18O spectra

More than 19,700 transitions belonging to 11 isotopologues of carbon dioxide have been assigned in the room temperature absorption spectrum of highly 18O enriched carbon dioxide recorded by very high sensitivity CW-Cavity Ring Down spectroscopy between 5851 and 6990 cm-1 (1.71-1.43 \mum). This third and last report is devoted to the analysis of the bands of five 17O containing isotopologues present at very low concentration in the studied spectra: 16O12C17O, 17O12C18O, 16O13C17O, 17O13C18O and 12C17O2 (627, 728, 637, 738 and 727 in short hand notation). On the basis of the predictions of effective Hamiltonian models, a total of 1759, 1786, 335, 273 and 551 transitions belonging to 24, 24, 5, 4 and 7 bands were rovibrationally assigned for 627, 728, 637, 738 and 727, respectively. For comparison, only five bands were previously measured in the region for the 728 species. All the identified bands belong to the \deltaP=8 and 9 series of transitions, where P=2V1+V2+3V3 is the polyad number (Vi are vibrational quantum numbers). The band-by-band analysis has allowed deriving accurate spectroscopic parameters of 61 bands from a fit of the measured line positions. Two interpolyad resonance perturbations were identified

A room temperature CO2_2 line list with ab initio computed intensities

Atmospheric carbon dioxide concentrations are being closely monitored by remote sensing experiments which rely on knowing line intensities with an uncertainty of 0.5% or better. We report a theoretical study providing rotation-vibration line intensities substantially within the required accuracy based on the use of a highly accurate {\it ab initio} dipole moment surface (DMS). The theoretical model developed is used to compute CO$_2$ intensities with uncertainty estimates informed by cross comparing line lists calculated using pairs of potential energy surfaces (PES) and DMS's of similar high quality. This yields lines sensitivities which are utilized in reliability analysis of our results. The final outcome is compared to recent accurate measurements as well as the HITRAN2012 database. Transition frequencies are obtained from effective Hamiltonian calculations to produce a comprehensive line list covering all $^{12}$C$^{16}$O$_2$ transitions below 8000 cm$^{-1}$ and stronger than 10$^{-30}$ cm / molecule at $T=296$~

An Abundance of K3 Fibrations from Polyhedra with Interchangeable Parts

Even a cursory inspection of the Hodge plot associated with Calabi-Yau threefolds that are hypersurfaces in toric varieties reveals striking structures. These patterns correspond to webs of elliptic-K3 fibrations whose mirror images are also elliptic-K3 fibrations. Such manifolds arise from reflexive polytopes that can be cut into two parts along slices corresponding to the K3 fibers. Any two half-polytopes over a given slice can be combined into a reflexive polytope. This fact, together with a remarkable relation on the additivity of Hodge numbers, explains much of the structure of the observed patterns.Comment: 30 pages, 15 colour figure

Цифровизация российской высшей школы: технологии образовательного процесса (опыт вузов Уральского федерального округа Российской Федерации)

The Russian higher school is in constant transformation, which is associated with the entry of the Russian Federation into the world market of educational services. To achieve the goals of positioning Russian universities in world rankings, various federal projects are being created, for example, within the framework of the state program “Development of Education” for 2019-2025, the project “Modern Digital Educational Environment in the Russian Federation” has been developed. To analyze the readiness of Russian universities for digital transformation, a study was conducted in which students of universities of the Ural Federal District (N = 300) took part, who evaluated the degree of implementation of various digital technologies in the educational process at the moment. It is for students as the main consumers of educational services to master the digital components of the educational process, to use technical means. The results of the study revealed the high willingness of students to work in a digital educational environment, the use of distance learning. Moreover, a higher level of readiness was demonstrated by students of technical and IT areas. At the same time, a contradiction was revealed between the readiness of students and their perception of the technical equipment of universities and the willingness of teachers to carry out the educational process in the new digital environment. Obviously, the use of centralized digital technologies (included by universities in the educational process) is significantly inferior to the students' spontaneous development of instant messengers, smartphone applications, and other software that facilitates the development of courses and disciplines (initiated by students on their own). Thus, to implement state programs to create a digital educational environment, it is necessary to strengthen the technical infrastructure of universities and improve the qualifications of teachers for the effective implementation of digitalization processes in higher education. © 2020 LLC Ecological Help. All rights reserved