Voronezh State University

About: Voronezh State University is a education organization based out in Voronezh, Russia. It is known for research contribution in the topics: Silicon & Boundary value problem. The organization has 5166 authors who have published 6097 publications receiving 31680 citations. The organization is also known as: VSU & Voronezh University.

Structure of the cluster ions of ketones in the gas phase according to ion mobility spectrometry and ab initio calculations

Abstract: Ion mobility spectra were recorded for linear aliphatic ketones with three to nine carbon atoms. Two most intense peaks were found to be the peaks of the monomer and dimer and used to calculate the reduced ion mobilities and the scattering (collision) cross sections (by the Mason-Schamp equation). The scattering cross sections increased linearly with the molecular mass. Based on the results of experiments and quantum-chemical calculations, it was concluded that the formation of the acetone dimer is accompanied by a decrease in the dipole moment of the structure relative to that of the monomer. For higher ketones, there is no compensation of the dipole moment.

Some problems of the qualitative Sturm-Liouville theory on a spatial network

Abstract: An analogue of the Sturm oscillation theory of the distribution of the zeros of eigenfunctions is constructed for the problem (*)on a spatial network (in other terms, is a metric graph, a CW complex, a stratified locally one-dimensional manifold, a branching space, a quantum graph, and so on), where is the family of boundary vertices of . At interior points of the edges of the quasi-derivative has the classical form , and at interior nodes it is assumed that where the summation is taken over the edges incident to the node and, for an edge , stands for the `endpoint' derivative of the restriction of the function to . Despite the branching argument, which is a kind of intermediate type between the one-dimensional and multidimensional cases, the outward form of the results turns out to be quite classical. The classical nature of the operator is clarified, and exact analogues of the maximum principle and of the Sturm theorem on alternation of zeros are established, together with the sign-regular oscillation properties of the spectrum of the problem (*) (including the simplicity and positivity of the points of the spectrum and also the number of zeros and their alternation for the eigenfunctions).