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Concrete production is a complex process, which consists of several important tasks. Design of concrete — the first and most demanding task in this list. Successful solving of this task determines the efficiency, reliability and safety of constructions.The paper is devoted to the use of mathematical and computer modeling for solving the problem of concrete designing for constructions of railways.A great amount of literature, which focuses on questions of concrete mix designing, is an indicator of the importance and relevance of the chosen direction.Methodology of concrete mix design, which has been developed in the Ukrainian Academy of Railways, provides a high mechanical and physical properties of concrete and selected as the basis.The methodology supplemented possibility of account of influence of plasticizers and additives hardening accelerators.Expediency and relevance of the use of information technology to solve the problem of designing the concrete composition confirmed by the existence of software for solving such problems (of both domestic and foreign developers), its active development and improvement, and positive experience of the authors in the development of such projects.The goal of research — the improvement of models, methods and algorithms designing of concrete for construction of railways.The model represents the mechanical state of the equation in the form of analytical dependence, which approximates the stress–strain diagram of core concrete elements. This model is considered as a parametric curve, the points of which are the result of the experimental curves. The basis of this model is the experimental dependence in the form of diagrams «s–e« (stress — strain). In experimental studies, different stress–strain diagram for the same concrete under different load conditions that exceed the limits of its long–term strength.Modeling of the deformation diagram of concrete and as a result, the definition of the strength characteristics of concrete made, Рассматриваются вопросы, связанные с моделированием бетона для конструкций и сооружений железных дорог. Приводится деформационная модель расчета бетона. Показана целесообразность использования информационных технологий для оценки прочностных характерис.тик бетона., Розглядаються питання, пов'язані з моделюванням бетону для конструкцій і споруд залізниць. Наведено деформаційну модель розрахунку бетону. Показано доцільність викорис.тання інформаційних технологій для оцінки характерис.тик міцності бетону.

© 2019, Pleiades Publishing, Ltd. The structure of the products of anodic oxidation of triphenylphosphine in the presence of camphene carried out in acetonitrile with sodium perchlorate as supporting electrolyte has been studied. The major product, triphenylphosphine oxide, has been isolated from the solution in the form of cocrystals of free triphenylphosphine oxide and its complex with sodium perchlorate. The molecular structure of the cocrystals has been studied by X-ray diffraction analysis. Triphenylcamphenylphosphonium perchlorate, bornylacetamide, and a terpene compound with triphenylphosphonium and acetamide substituents in the cycle have been detected by NMR 13C as the electrolysis side products.

On of the products of electrochemical phosphorylation of camphene was 2-(C-methyl-C-trialkylphosphonio) methyleneimino-10-trialkylphosphoniomethyl) bornane diperhlorates. A mechanism of their formation was suggested consisting in the rearrangement of the intermediate camphenylphosphonium dication followed by selective addition of acetonitrile and a second trialkylphosphine molecules. The diperhlorate hydrolysis was found to lead to the synthesis of 2-acetamido-10-trialkylphosphoniobornane perchlorates. The 2-(C-methyl-C- tripropylphosphonio)methyleneimino-10-tripropylphosphoniomethyl)bornane and 2-acetamidoyl-10-tripropylphosphoniobornane structures were established by the X-ray diffraction study. © 2013 Pleiades Publishing, Ltd.

Anodic oxidation of tertiary phosphines (tripropyl-, tributyl-, and triphenylphosphine) in the presence of a bicyclic alkene (camphene) on a platinum and a glassy carbon electrodes was studied. For the first time the voltammetric characteristics of the process of camphene anodic oxidation were obtained. The electrochemical reactions with alkyl and aromatic phosphine were found to be dissimilar. The results of preparative electrooxidation of trialkylphosphines showed that in the course of electrolysis the tertiary phosphine cation-radicals generated on the anode enter into two concurrent reactions: (1) with the parent phosphine to form eventually trialkylphosphonium salts and trialkylphosphine oxides presumably as complex compounds and (2) with camphene to form trialkylcamphenylphosphonium salts and probably phosphonium salts with a monocyclic substituent. Preparative electrochemical oxidation of triphenylphosphine in the presence of camphene affords almost exclusively either triphenylphosphine oxide (in the experiment with platinum anode) or the triphenylphosphine oxide complex with perchloric acid (at the electrolysis on a glassy carbon anode). © 2009 Pleiades Publishing, Ltd.

Anodic oxidation of tertiary phosphines (Et 3P, Pr 3P, Bu 3P, i-Bu 3P and Am 3P) in the presence of camphene and heterogenic base (trisodium phosphate) on platinum anode in acetonitrile solution of sodium perchlorate was studied. It is established that trialkylphosphine radical cations react with camphene to give two types of products: Camphenylphosphonium salts formed by elimination of proton, and phosphiniminoterpenylphosphonium salts which are obtained due to the rearrangement of terpenyl skeleton. Conditions of electrosynthesis are found where the summary yield of terpenylphosphonium products increases. The effect of length and degree of branching of alkyl substituents in trialkylphosphines on the rate of the reaction of phosphine radical cations with camphene and starting phosphine is found. © Pleiades Publishing, Ltd., 2012.

Single crystal XRD is used to analyze the crystal structure of triethylcamphenylphosphonium salt produced during the electrochemical oxidation of triethylphosphine in the presence of camphene. © 2012 Pleiades Publishing, Ltd.

On of the products of electrochemical phosphorylation of camphene was 2-(C-methyl-C-trialkylphosphonio) methyleneimino-10-trialkylphosphoniomethyl) bornane diperhlorates. A mechanism of their formation was suggested consisting in the rearrangement of the intermediate camphenylphosphonium dication followed by selective addition of acetonitrile and a second trialkylphosphine molecules. The diperhlorate hydrolysis was found to lead to the synthesis of 2-acetamido-10-trialkylphosphoniobornane perchlorates. The 2-(C-methyl-C- tripropylphosphonio)methyleneimino-10-tripropylphosphoniomethyl)bornane and 2-acetamidoyl-10-tripropylphosphoniobornane structures were established by the X-ray diffraction study. © 2013 Pleiades Publishing, Ltd.

Anodic oxidation of tertiary phosphines (Et 3P, Pr 3P, Bu 3P, i-Bu 3P and Am 3P) in the presence of camphene and heterogenic base (trisodium phosphate) on platinum anode in acetonitrile solution of sodium perchlorate was studied. It is established that trialkylphosphine radical cations react with camphene to give two types of products: Camphenylphosphonium salts formed by elimination of proton, and phosphiniminoterpenylphosphonium salts which are obtained due to the rearrangement of terpenyl skeleton. Conditions of electrosynthesis are found where the summary yield of terpenylphosphonium products increases. The effect of length and degree of branching of alkyl substituents in trialkylphosphines on the rate of the reaction of phosphine radical cations with camphene and starting phosphine is found. © Pleiades Publishing, Ltd., 2012.

Anodic oxidation of tertiary phosphines (tripropyl-, tributyl-, and triphenylphosphine) in the presence of a bicyclic alkene (camphene) on a platinum and a glassy carbon electrodes was studied. For the first time the voltammetric characteristics of the process of camphene anodic oxidation were obtained. The electrochemical reactions with alkyl and aromatic phosphine were found to be dissimilar. The results of preparative electrooxidation of trialkylphosphines showed that in the course of electrolysis the tertiary phosphine cation-radicals generated on the anode enter into two concurrent reactions: (1) with the parent phosphine to form eventually trialkylphosphonium salts and trialkylphosphine oxides presumably as complex compounds and (2) with camphene to form trialkylcamphenylphosphonium salts and probably phosphonium salts with a monocyclic substituent. Preparative electrochemical oxidation of triphenylphosphine in the presence of camphene affords almost exclusively either triphenylphosphine oxide (in the experiment with platinum anode) or the triphenylphosphine oxide complex with perchloric acid (at the electrolysis on a glassy carbon anode). © 2009 Pleiades Publishing, Ltd.

Single crystal XRD is used to analyze the crystal structure of triethylcamphenylphosphonium salt produced during the electrochemical oxidation of triethylphosphine in the presence of camphene. © 2012 Pleiades Publishing, Ltd.