Разработка устройства для получения самостоятельного газового разряда

В данной статье рассматривается сборка генератора высокого напряжения из подручныхматериалов, прототип может быть использован для учебных и исследовательских целей

ВНУТРЕННИЕ ОСТАТОЧНЫЕ НАПРЯЖЕНИЯ В ПОКРЫТИЯХ, СФОРМИРОВАННЫХ ЭЛЕКТРОМАГНИТНОЙ НАПЛАВКОЙ

The paper presents methods for determination of parameters pertaining to linear-stressed metal state over a roentgenogram line offset. Results of residual macro-stress determination in coatings, formed in the electromagnetic field are cited in the paper. The paper contains an analysis of residual stress values of coatings depending on chemical composition of powders and methods of mechanical machining.Приводится метод определения параметров линейно-напряженного состояния металла по смещению линий рентгенограммы. Представляются результаты определения остаточных макронапряжений покрытий, сформированных в электромагнитном поле. Дается анализ значений остаточных напряжений в покрытиях в зависимости от химического состава порошков и методов механической обработки

PLM-COMPETENCE FORMATION USING COMPUTATIONAL-GRAPHICAL PRACTICE

The description of a new kind of learning activity “Computational - graphical practice” is presented. This practice aimed at consolidating the knowledge and skills acquired by students in the study of the basic engineering disciplines and bridge the gap in the training of students in the field of PLM-technology. The goals, objectives, program practices and competencies, which should have a student after passing the training practice, are liste

Influence of anionic surfactant on stability of nanoparticles in aqueous solutions

Dispersion and aggregation of nanoparticles in aqueous solutions are important factors for safe and effective application of nanoparticles, for instance, in the oil industry. As conventional oil reserves are depleted, it is necessary to advance chemical enhanced oil recovery (cEOR) techniques to develop unconventional oil reservoirs. Nanoparticles modified by surfactants can be a promising reagent in cEOR. These nanomaterials can reduce interfacial tension and change the wettability of reservoir rock, which leads to an increase in oil recovery. However, the application of nanoparticles is limited by their substantial aggregation in aqueous solutions. The purpose of this work is to select nanoparticles for obtaining stable sols in water in the presence of an anionic surfactant and to optimize the conditions (pH) for further modifying the nanoparticles with the anionic surfactant. Sodium dodecyl sulfate (SDS) is used as an anionic surfactant. The aggregation of oxide and carbon nanoparticles in water and anionic surfactant solutions was studied by laser diffraction, dynamic and electrophoretic light scattering methods. Most of the studied nanoparticles in water form aggregates with bi-, three- and polymodal particle size distributions. TiO2 nanoparticles obtained by plasma dynamic synthesis form the most stable sols in anionic surfactant solutions. The range of 5–7 pH is defined as optimal for their modification with surfactants. The stability of carbon nanoparticles in aqueous solutions increases significantly in the presence of a surfactant. The obtained results form the basis for further research on the modification of marked nanoparticles in surfactant solutions

МИРНЫЕ ЯДЕРНЫЕ ВЗРЫВЫ В АРХАНГЕЛЬСКОЙ ОБЛАСТИ И ОТНОШЕНИЕ НАСЕЛЕНИЯ К ИХ ПОСЛЕДСТВИЯМ

The article presents survey results for local population attitude to the issue of peaceful nuclear explosions (PNE) performed in the last century on the territory of the Arkhangelsk region. Complex radiationhygienic study showed the absence of radioactive contamination in the communities most close to PNE locations. The vast majority of most socially active groups of responding population groups do not experience anxiety, they feel safe, confident and full of hope. However, they are fully aware of radiation risks related to PNE consequences. The population is willing and ready to receive objective information about PNE consequences from sources which it trusts. Recommendations on informing the public about the PNE problem are given.В статье приводятся результаты изучения отношения местного населения к проблеме мирных ядерных взрывов (МЯВ), проведенных в 1971–1988 гг. на территории Архангельской области. Комплексное радиационно-гигиеническое исследование показало отсутствие радиоактивных загрязнений в местах проживания, наиболее близко расположенных к местам осуществленных МЯВ. Подавляющее большинство опрошенных наиболее социально активных групп населения не испытывают тревоги, чувствуют себя спокойными, уверенными в себе и полными надежд. Однако они высоко оценивают опасность радиационной обстановки в связи с последствиями МЯВ. Население хочет и готово принять объективную информацию о последствиях МЯВ из источников, которым оно доверяет. Даны рекомендации по вопросам информирования населения о проблеме МЯВ

Роль магнитно-резонансной томографии в выборе тактики ведения пациентов с механической желтухой

The aim за this study was to estimate capabilities of magnetic-resonance imaging in diagnostics of patients with obstructive jaundice syndrome. Magnetic-resonance imaging was made for 112 patients with biliary hypertension. Malignancy was found in 31 (27.6%) cases случае, mostly in men and mostly cancer of the head of the pancreas. Noncancerous genesis in 74 (66.1%) cases was mostly represented by cholelithiasis and most often in women.Цель работы — оценить возможности магнитно-резонансной томографии в диагностике пациентов с синдромом механической желтухи. Магнитно-резонансная томография, включая магнитно-резонансную холангиопанкреатографию, выполнена 112 пациентам с билиарной гипертензией. Злокачественный характер выявлен в 31 (27,6%) случае, преобладал рак головки поджелудочной железы, преимущественно у мужчин. Доброкачественный генез в 74 (66,1%) наблюдениях был зачастую представлен холелитиазом и наиболее распространен у женщин

CAD and 3d-printing integration experience in the curriculum of engineers education

The paper examines the results of using the 3d-printing educational methodology for training the students in the spacecraft-configuration developing area.The first purpose of the considered methodology practice is to implement the rapid-prototyping skills into the educational process, to provide perfection of the student knowledge in configuring the internal on-board equipment of the spacecraft. The second purpose – is to habituate the students to the main principles of the available CAM technologies, to fill the available educational gap in the area of information support of the spacecraft life-cycle.The proposed curriculum includes six training exercises based on a special “Engineering drawing” course unit. The training exercises require using the SolidWorks geometric-simulation software. The preliminary obtained virtual prototypes of the spacecraft configuration elements are subjected to 3d-printing and assembled into a physical configuration model. The physical configuration models are obtained using one of the most accessible rapid-prototyping technologies – 3d-printing of extrusion type. Practicing in 3d-printing provides developing the student skills in managing all other digital-program control devices.The specified first experience of integrating the computer geometricsimulation methodology and the 3d-printing practices in a single course unit has proved: developing the physical-configuration models heightens the student interest to the configuration training.A ready-made physical model does not excuse the available configuration mistakes unlike a virtual model where the component interferences may remain undetected. So, developing a physical model requires additional endeavor and responsibility. Developing a project in a team has proved to be an effective means for solving a common creative problem.The first test of the proposed methodology has shown the importance of perfect adjustment of the available 3d-printing process and the Slicer program. The part-model manufacture cycle requires approximately from 2 to 3 hours per a component (from 1 to 1.5 hours for 3d-printing in that account). Large-scale blocks shall represent an assembly (containing a block body and a lid) to reduce the printing-plastic consumption. Average printing-plastic consumption is about 1 kg per a configuration model. The obtained 3d-printing experience shows that the printing speed is much more important than the printing accuracy for the given educational problem.The obtained educational-methodology test results are considered to be a success. It is recommended to purchase an additional high-productivity 3d-printer facility providing an effective fascinating spacecraftconfiguration process

INTERNAL RESIDUAL STRESSES IN COATINGS FORMED BY ELECTRO-MAGNETIC SURFACING

The paper presents methods for determination of parameters pertaining to linear-stressed metal state over a roentgenogram line offset. Results of residual macro-stress determination in coatings, formed in the electromagnetic field are cited in the paper. The paper contains an analysis of residual stress values of coatings depending on chemical composition of powders and methods of mechanical machining