Effect Of Dynamic Characteristics of Power Supplies on Aerosol Composition While Welding With Coated Electrodes

In the context of a significant increase in production output and use of welding technologies in the manufacturing of engineering products the problem of hygienic characteristics of working conditions in arc fusion welding is becoming increasingly important. The work represents how the dynamic characteristics of a power supply affect the transfer of alloying elements from a coated electrode into a base metal, a slag phase and a solid component of welding fumes

Improving Hygienic Characteristics of Coated Electrodes for Welding High-Alloy Steels

The article presents the results of experimental studies showing that the use of an inverter power supply instead of a diode rectifier provides:: fine-droplet electrode metal transfer which reduces generation time by 46% and transfer time by 28%; transfer of alloying elements from welding materials into the weld metal which reduces its loss from the welding line by 6% and the heat affected area by 3%; reducing the emission rate of welding fumes and their components by 23%; reducing specific emission of welding fumes and their components by 23%

Development of methods for the preparation of radiopure ⁸²Se sources for the SuperNEMO neutrinoless double-beta decay experiment

A radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8-54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.</p

DEVELOPMENT OF MOBILE ELECTRONIC CARDS

Главным конкурентным преимуществом разрабатываемого сервиса является возможность анализа по использования карты и простота интеграции сервиса с базой клиента. При создании сервиса решались вопросы предоставления клиентам удобного пользовательского интерфейса. Удалось максимально упростить процесс создания шаблона карты. Приведены результаты разработки аналитических средств по использованию карт. Разработан инструментарий для интеграции сервиса в бизнес логику компании партнера. Сервис разрабатывался с учетом масштабируемости. Решены вопросы с распределением нагрузки при массовом подключении клиентов к сервису. Проведена разработка готовых решений для интеграции с популярными системами управления взаимоотношениями с клиентами 1С, R-kеереr, Iiko.The work is devoted to developing a server application that generates electronic cards. The main competitive advantage is the ability to tailor services for the analysis of card use and ease of integration of the service with the customer base. When you create a service we decide on the granting customers a user-friendly interface. It was possible to simplify the process of creating a template card. The results of the development of analytical tools for the use of cards. Developed tools for service integration in the business logic of the partner company. Service was designed with scalability in mind. The issues with the distribution of the load in mass clients connect to the service. Spend the development of turnkey solutions for integration with popular customer relationship management 1C, R-keerer, Iiko

Purification of selenium from thorium, uranium, radium, actinium and potassium impurities for low background measurements

Summary A technique of selenium purification from 232Th, 238U, 226,228Ra, 227Ac and 40K was developed. This technique is simple to perform and employs a minimum number of highly pure reagents (bidistilled water, nitric acid). Operations carried out during purification (elution, evaporation) practically exclude losses of the target product (chemical yields of Se &gt; 99%). A test purification of 100 g of selenium was carried out using this technique. The efficiency of this technique was confirmed by low background gamma spectrometry of the purified selenium sample. Distribution coefficients of Th, U, Ra and Ac on DOWEX 50W-×8 cation-exchange resin at different concentrations of selenium and nitric acid were experimentally determinated. Instrumental neutron activation analysis of bidistilled water, deionized water and nitric acid was performed.</jats:p

Copolymerization of N-[3-dialkylaminopropyl]methacrylamides with acrylic amides and esters in organic solvents

The radical copolymerization of N-[3-(dialkylamino)-propyl]methacrylamides with a number of (meth)acrylic amides and esters in organic solvents over a wide range of molar ratios has been studied. Co-polymerisation constants for five polymerisation systems in 1,4-dioxane and toluene have been determined by the Feinman and Ross method. The influence of the solvent on the kinetics of the copolymerization of the studied monomers was found, which manifests itself in a change of the reactivity ratios of the monomers upon varying the polarity of the medium. For the obtained polymers, the presence of thermosensitive properties in aqueous solutions and the effect of the concentration and composition of copolymers on their solubility in water were shown.</jats:p