Проектирование параметрического маховика с использованием новых технологий

Статья содержит один из способов оптимизации характеристик маховика исполнительногооргана системы ориентации малого космического аппарата на основе анализа математической моделимаховика. Математическая модель позволяет оценить взаимное влияние его характеристик и установитьсвязи между ними, которые напрямую не определяются. Наиболее эффективным методом оптимизациихарактеристик является варьирование параметров конструкции через параметризацию с использованиемспециализированного программного обеспечения, реализующего геометрическую параметризацию ивозможность эффективного расчета требуемых характеристик. Создается параметрическая 3D-модель,включающая в себя расчет эксплуатационных характеристик. Варьированием параметров 3D-моделивозможно получить оптимальный комплекс эксплуатационных параметров. Это весьма актуально наэтапе проектирования, поскольку позволяет существенно повысить качество проектируемого устройстваи сократить общее время проектирования.Article contains a optimization ways of a flywheel characteristics of the navigation executive body systemof the small spacecraft on the basis of the a flywheel mathematical model analysis. The mathematical model allowsto estimate mutual influence of his characteristics and to establish connection between them which directly aren'tdefined. The variation of a design parameters through parametrization with use of the specialized software realizinggeometrical parametrization and a possibility effective calculation of the required characteristics is the mosteffective method of optimization of characteristics. The parametrical 3D model including calculation of operationalcharacteristics is created. It is possible to receive an optimum complex of operational parameters a variation of a3D model parameters. It is very actual at a design stage as allows to increase significantly quality of the designeddevice and to reduce the general time of design

Combined Extended High Spinal Anesthesia and Endotracheal Narcosis: a Clinical Case

Background. In recent years, various methods of combined anesthesia during abdominal surgery have been introduced into clinical practice.Aim. To demonstrate the possibilities of a combination of high prolonged spinal anesthesia and endotracheal anesthesia during abdominal surgery.Materials and methods. A clinical case of combined use of high prolonged spinal anesthesia and endotracheal anesthesia in a 48-year-old patient with a tumor in the right half of the ascending part of the right half of the colon is presented.Results. The patient received a puncture of the spinal space at a standard point and was installed a spinal catheter in the cranial direction for 3 cm. An isobaric solution of marcaine in the initial dose of 20 mg was injected into the catheter. The regulation of the development of the block was regulated by the inclination of the head end of the table by 60°. After that endotracheal anesthesia was performed on the basis of fentanyl and propofol. This combination allowed to expand the scope of surgical intervention, provided adequate pain relief intraoperatively and in the postoperative period, without the use of narcotic analgesics. With the appearance of signs of recovery of pain sensitivity, intraoperatively or in the postoperative period, re-introduction of the anesthetic into the spinal catheter was performed in half of the initial dose with liquor barbotage. In the early postoperative period, the patient was on strict bed rest with a head end of the bed raised at 30–45°. The method provides complete segmental blockade and muscle relaxation in the area of operation, stability of central hemodynamics during surgery and in the postoperative period.Conclusion. This type of anesthesia is more easily tolerated by patients, accompanied by early awakening and extubation, characterized by stability of central hemodynamics, reduced risk of complications, the possibility of prolonging anesthesia with lower doses of narcotic analgesics in the intraoperative period, providing high-quality anesthesia in the postoperative period without resorting to the use of narcotic analgesics

Gating system design for the space device case using T-Flex CAD

The judicious selection of gating system for the consumable pattern takes a lot of time, labour and other significant resources. The modern design technologies provide quick and effective ways for gating system calculation and casting process simulation. Gating system modeling allows estimating different kinds of defects which can occur at the developing stage of casting process. Moreover, it is possible to modify the whole gating system configuration if some parameters are changed. Analyzing these data and modifying the gating system characteristics high quality of castings can be achieved

Designing of space oriented body parts with the use of modern technologies

Proper selection of the gating system for investment pattern is a long and labor-intensive process that requires significant resources. The latest design technologies enable the calculation of the gating system and simulation of the casting process based on these calculations. Simulation and calculation of the gating system make it possible to determine defects which occur during the casting process at the design stage. The result of simulation is the distribution of flow and temperature velocity vectors. The process of cooling and crystallization is simulated, as well as a mold filling process. Analyzing these data and changing the characteristics of the gating system, it is possible to achieve the very high quality of castings

On the role of carbon support in the catalytic wet peroxide and air oxidation of organic contaminants

SSCI-VIDE+CARE:CDFA+CDS:MBEInternational audienceNon

Sibunit-Based Catalytic Materials for the Deep Oxidation of Organic Ecotoxicants in Aqueous Solutions. III: Wet air oxidation of Phenol over Oxidized Carbon and Ru/C Catalysts

International audienc

Ruthenium nanoparticles supported on nitrogen-containing carbon nanofibers for CWAO of phenol

SSCI-VIDE+CARE:CDFA+CDS:MBEInternational audienceNon

Sibunit-Based Catalytic Materials for the Deep Oxidation of Organic Ecotoxicants in Aqueous Solutions. III: Wet air oxidation of Phenol over Oxidized Carbon and Ru/C Catalysts

International audienc

Methane Catalytic Peroxide Oxidation Over Fe-Containing Zeolite

Изучена селективность Fe-MFI-катализаторов в парциальном пероксидном окислении метана до метанола и муравьиной кислоты в зависимости от их топологии (нанокристаллы, микрокристаллы и массивный коммерческий) и активации щавелевой кислотой. Катализаторы изучены методами РФА, ИСП-ОЭС, СЭМ, ЭСДО, ТПД- NH3, адсорбции N2. TOF окисления метана увеличивается в ряду: нанокристаллы < микрокристаллы << коммерческий. Селективность по метанолу зависит главным образом от размера кристаллитов и увеличивается в том же ряду. Увеличение TOF и селективности по муравьиной кислоте, а также резкое снижение селективности по CO2 на всех активированных катализаторах были объяснены увеличением общей кислотности катализаторов и количества олигомерных оксокластеров железа. Высказано предположение о различных путях образования метанола/ CO2 (по свободнорадикальному маршруту) и муравьиной кислоты (по гетерогенному маршруту) на катализаторах Fe-MFIThe selectivity of Fe-MFI catalysts to partial peroxide oxidation of methane to methanol and formic acid was studied depending on their topology (Nanocrystals, Microcrystals, and bulk Commercial) and activation with oxalic acid. The catalysts were characterized by XRD, ICP-OES, SEM, UV-vis DR, NH3-TPD, N2 adsorption. TOF of methane oxidation increased in the series: Nanocrystals < Microcrystals << Commercial. The selectivity to methanol depended mainly on the crystallite size and increased in the same series. The increase in TOF and selectivity to formic acid, as well as a sharp decrease in the selectivity to CO2 over all the activated catalysts were accounted for by an increase in the total acidity of the catalysts and the number of oligomeric Fe oxo-clusters. Different pathways to the formation of methanol/CO2 (via free radical mechanism) and formic acid (via heterogeneous route) over Fe-MFI catalysts were suggeste