47 research outputs found

    Control system of parameters of the azimuthal module

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    Analytical and experimental studies of the azimuthal module of two-component vibrational micromechanical gyroscope were conducted. It is shown that the micromechanical gyroscope is a system with distributed parameters. The frequency analysis is performed using software T-Flex. The influence of mechanical disturbances on the movement of azimuthal module in the form of translational and angular oscillations is shown; the natural frequencies of the azimuth are defined

    Physico-chemical Modification of the Fibrous Filter Nozzles for Purification Processes of Water and Air

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    A set of experiments to study physical and chemical modification of the surface of fibers is conducted to expand the area of their application for purification of water, gas and air (including that in conditions of space). The possibility of modification of filter nozzles in the process of fiber formation by particles of coal of BAU type, copper sulfide and silver chloride is experimentally shown. The fraction of the copper sulfide powder less than 50 microns in size was crushed in a spherical mill; it was deposited on fiber at air temperature of 50Β° C and powder consumption of 0.5 g/l of air. The resulting material contained 6–18 CuS particles per 1 cm of the fiber length. An effective bactericidal fibrous material can be produced using rather cheap material – CuS and relatively cheap natural compounds of sulphides and oxides of heavy metals

    Monitoring and Quality Control of Diesel Fraction Production Process

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    In this work the mathematical model of diesel fraction and atmospheric gasoil catalytic dewaxing process has been developed. Also the pattern of applying the created model to solving such problems as monitoring and quality control of diesel fraction production in the catalytic dewaxing process. It has been represented that to meet such challenges, the model should take into consideration thermodynamic and kinetic laws of hydrocarbon conversion on the catalyst surface, and instability factors that are specified by catalyst deactivation. The developed model allows controlling the quality of obtained diesel fraction depending on feed and temperature regime in the reactor. The value of model calculation absolute error does not exceed 2%, which corroborates the adequacy of the model to actual process. The computations using the model have shown that to provide the desired product yield (not less than 40% wt. of overall yield of the unit products) of programmed quality (cold filtering plugging point not higher than minus 34Β°C for winter diesel fuels and not lower than minus 40Β°C for arctic ones) at long-time catalyst operation (during 4 years), it is necessary to sustain the reactor temperature at the average level of 19Β°C higher than when working with fresh catalyst. This must be done to compensate catalyst activity loss due to its deactivation

    The development of radio and 3G based telemetry system for the remote gas accounting and control nodes

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    In this article we have described the use of vortex and recently developed ultrasonic flowmeters with high dynamic range of 1 to 1500 for industrial applications. Its software and the software of corresponding computing device is able to avoid gas leakage, to minimize energy consumption and to save human resources while maintaining metrological data. Described is the low power consumption that makes it possible to use this ultrasonic flowmeter in hard remote environment without direct management for a period of several month

    LEDs based upon AlGaInP heterostructures with multiple quantum wells: comparison of fast neutrons and gammaquanta irradiation

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    The paper presents the research results of watt and volt characteristics of LEDs based upon AlGaInP heterostructures with multiple quantum wells in the active region. The research is completed for LEDs (emission wavelengths 624 nm and 590 nm) under irradiation by fast neutron and gamma-quanta in passive powering mode. Watt-voltage characteristics in the average and high electron injection areas are described as a power function of the operating voltage. It has been revealed that the LEDs transition from average electron injection area to high electron injection area occurs by overcoming the transition area. It disappears as it get closer to the limit result of the irradiation LEDs that is low electron injection mode in the entire supply voltage range. It has been established that the gamma radiation facilitates initial defects restructuring only 42% compared to 100% when irradiation is performed by fast neutrons. Ratio between measured on the boundary between low and average electron injection areas current value and the contribution magnitude of the first stage LEDs emissive power reducing is established. It is allows to predict LEDs resistance to irradiation by fast neutrons and gamma rays

    Evaluation of the potential accuracy of the pulsed radio signals source coordinate determination by the positioning system using a single UAV-sensor

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    An approach to determining the coordinates of pulsed radio signals sources by the positioningsystem in the application of a single unmanned aerial vehicles sensor is shown in this article. Therange-difference location method allows to determinate an informative coordinate parameter withoutretransmission and internal synchronization of receiving points. The result is achieved by improving thewell-known scientific and methodological apparatus with considering some features of the operationmode of pulsed radio signals sources. Presenting results of the simulation allow to estimate theinfluence of main input factors on the potential accuracy of the pulsed radio signal source coordinatedetermination

    Pneumatic device of the preload and dynamic loads balancing to reduce the intensity of thermal processes in the metal cutting process

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    Improved reliability of the technological system "machine-tool-instrument-detail" is an important current task. Backlashes and insufficient stiffness of technological system lead to intensive wear of the cutting tool, increasing the heat in the cutting zone. Due to high temperature in the thin surface layers of the workpiece and tool thermal processes may occur which are similar to release and can cause the structural changes of the material. The current article presents the final design of the device which has been developed to reduce the intensity of thermal processes in metal cutting

    Determination technique of quasireference value of a carrier radio signal frequency of uncooperated onboard lighting source during radio monitoring

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    The article discloses the technique defining quasireference value of a carrier radio signal frequency of uncooperated onboard lighting source by calculation and compensation of the Doppler shift at radio monitoring. Provided simulation results show checked operability of the offered technique with assessment of observation accuracy and received quasireference value of a carrier frequency accepted a radio signal compared with real sample under various conditions

    STUDY OF MINIMAL RESIDUAL DISEASE BY MULTICOLOR FLOW CYTOMETRY IN MULTIPLE MYELOMA AFTER AUTOLOGOUS HEMATOPOIETIC STEM CELL TRANSPLANTATION

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    The frequency of achieving complete remission, as well as overall and disease-free survival, in multiple myeloma (MM) had increased due to introduction in MM treatment regimens of high-dose chemotherapy with following autologous hematopoietic stem cell transplantation (ASCT). However the number of relapses remains high, caused by persistence of residual tumor cells, i.e., the presence of minimal residual disease (MRD). One of the methods for MRD study is multicolor flow cytometry (MFC) where abnormal expression of surface antigens on myeloma plasma cells (PC) is determined. The aim of our study was to investigate the MRD by MFC before and after ASCT, the frequency of MRD-negative status achievement in complete remission (CR) patients at +100 days after ASCT and the frequency of abnormal expressed antigens on myeloma plasma cells. The study included40 MMpatients in CR at +100 days after ASCT and showed that the most common aberrations of PC were: abnormal absence of CD19 and/or CD27, decreased expression of CD38 and abnormal presence of CD56. The proportion of myeloma PCs from all bone marrow cells decreased significantly after ASCT: 20 % of patients acquired MRD-negative status, 10 % had a decrease in the number of abnormal PCs by one fold. Analysis of probability of immunochemical relapse showed that the worst prognosis was in patients with MRD-positive status before and after ASCT. During the MRD monitoring within 3-18 months, MRD-relapses were detected with the subsequent development of immunochemical relapse. The detection MRD in the dynamics is more informative than the study at only one step of therapy. It may help to select more adequate treatment for patient with multiple myeloma in each specific case

    Diagnostics and treatment challenges of Ph-like acute lymphoblastic leukemia: a description of 3 clinical cases

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    B-cell acute lymphoblastic leukemia (B-ALL) is a diverse group of malignant blood disorders both with regard to the biological properties of the tumor and to therapeutic approaches. Immunophenotyping, molecular genetic techniques, whole-genome sequencing characterize B-ALL as a very diverse group for sensitivity to chemotherapy and prognosis. We present three clinical cases of patients with B-ALL and expected good response to standard therapy, in whom standard protocol treatment failured: refractoriness, persistence of minimal residual disease (MRD), and progression (MRD increase). The remission in these patients was achieved after chemotherapy change to immunological targeted therapy. Nowadays a unified therapeutic approach to all primary patients of the B-ALL is considered generally outdated. Great efforts are carrying out to develop molecular genetic classifications. The molecular dissection of subtypes of B-ALL goes on, and new protocols for selective treatment with targeting are clearly outlined for each subtype of B-ALL
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