scholarly journals Determination of Methodology and Research of the Influence of the Trial Run of High-Precision Reducers on the Change of Their Characterizing Properties

2021 ◽  
Vol 11 (9) ◽  
pp. 3859
Author(s):  
Marek Kočiško ◽  
Martin Pollák ◽  
Monika Töröková ◽  
Petr Baron ◽  
Dušan Paulišin ◽  
...  
Keyword(s):  
High Precision ◽  
Dynamic Properties ◽  
Critical Parameters ◽  
Positioning Accuracy ◽  
Subsequent Determination ◽  
Wide Range ◽  
Correct Implementation

This paper describes, in detail, the research of the influence of the trial run of high-precision reducers on the change of their characterizing parameters with the subsequent determination of the methodology for the identification of their critical parameters and positioning accuracy. The research was carried out on a sample of high-precision reducers during a 48 h run-in with the evaluation of changes in their characterizing parameters. The developed methodology unifies the approach to measuring the static and dynamic properties of high-precision reducers to identify their critical parameters and positioning accuracy. The article also points to the need for the correct implementation of the process for the introduction of the bearing reducer into operation after its incorporation into the relevant equipment with emphasis on improving the monitored critical parameters. The running-in of reducers is a little-explored area in terms of its effect on changing the wide range of characterizing properties of high-precision reducers. At the same time, it is complicated by the non-existent uniform methodology for the implementation of their run-in.

Dynamic Properties of a Circuit Breaker with Friction-Based Seismic Dampers

1996 ◽  
Vol 12 (2) ◽  
pp. 297-314 ◽  
Author(s):  
R. Kar ◽  
J. H. Rainer ◽  
A. C. Lefrançois
Keyword(s):  
Design Parameter ◽  
Natural Frequencies ◽  
Dynamic Properties ◽  
Circuit Breaker ◽  
Ground Acceleration ◽  
Discrete Parameter ◽  
Wide Range ◽  
Sf6 Circuit Breaker ◽  
Energy Dissipated

The design parameter of 1.05 g peak seismic ground acceleration for a 300 kV SF6 circuit breaker necessitated the provision of supplemental friction-based dampers. This paper describes the dampers and the dynamic properties of the circuit breaker as obtained from a series of pull-release tests with increasing force amplitudes. These tests permitted a determination of a wide range of damping ratios and natural frequencies as a function of displacements. A comparison is also presented between the measured and the calculated damping ratios and frequencies, using common engineering approximation of the energy dissipated per cycle for damping, and a discrete parameter and linearized stiffness approach for the calculation of natural frequency. Reasonable comparisons were achieved between the measured and calculated values.

scholarly journals Adsorption-Semiconductor Sensor Based on Nanosized SnO2 for Early Warning of Indoor Fires

2021 ◽  
Author(s):  
Nelli Maksymovych ◽  
Ludmila Oleksenko ◽  
George Fedorenko
Keyword(s):  
Tin Dioxide ◽  
Early Stage ◽  
Dynamic Properties ◽  
Sol Gel ◽  
Average Particle Size ◽  
High Sensitivity ◽  
Average Particle ◽  
Semiconductor Sensor ◽  
Wide Range

The paper is devoted for a solution of indoors fires prevention at early stage by determination of H2 (fire precursor gas) in air using a semiconductor sensor. A material based on Pt-containing nanosized tin dioxide with an average particle size of 10–11 nm obtained via a sol–gel method was created for a gas sensitive layer of the sensor. The developed sensor has high sensitivity to H2 micro concentration, a wide range of its detectable content in air, selectivity of H2 measuring in the presence of СО and СН4, good dynamic properties. The combination of these properties is very important for prevention of inflammations on their early stages before the open fires appearance. Economic benefit of the proposed sensor is due to a lower cost and higher reliability of the fire situation detection.

Determination of the liquid evaporation rate when categorizing rooms and outdoor installations

2020 ◽  
pp. 120-129
Author(s):  
Геннадий Тимофеевич Земский ◽  
Владимир Александрович Зуйков ◽  
Александр Валерьевич Ильичев ◽  
Наталья Валентиновна Кондратюк ◽  
Александр Владимирович Зуйков
Keyword(s):  
Evaporation Rate ◽  
Saturated Vapor ◽  
State Diagram ◽  
Critical Parameters ◽  
Normative Documents ◽  
Ambient Temperatures ◽  
Wide Range ◽  
Evaporation Intensity ◽  
Liquid Evaporation

Возможность взрыва паровоздушной смеси при аварийном проливе жидкости из технологического аппарата во многом зависит от интенсивности испарения жидкости. Для определения интенсивности испарения существуют уравнения, в которые входят величины, характеризующие свойства жидкости, условия ее нахождения в аппарате перед аварией и условия, в которые попадает выливающаяся жидкость. Критически рассмотрены известные уравнения для определения интенсивности испарения, начиная от уравнения Ленгмюра - Кнудсена и заканчивая уравнениями, вошедшими в нормативные документы по обеспечению пожарной безопасности. Рассмотрены варианты аварийного пролива пожароопасных жидкостей в зависимости от сочетания следующих температур: температуры кипения жидкости, температуры вспышки жидкости, температуры жидкости до пролива и температуры окружающей среды. The possibility of an explosion of a steam-air mixture in the event of an emergency spillage of liquid from the process apparatus largely depends on the liquid evaporation intensity. The evaporation intensity is influenced by the following factors: the properties of the liquid (such as critical parameters, liquid temperature, saturated vapor pressure, flash point) as well as the temperature and pressure of the surrounding atmosphere. To determine the intensity of evaporation there are equations that include values that characterize the properties of the liquid, the conditions of its presence in the device before the accident, and the conditions for the spilling liquid after the accident. There is critically considered the wide range of known equations for determining the evaporation intensity beginning with the Langmuir-Knudsen equation and ending with the equations included in the normative documents on fire safety. The Langmuir-Knudsen equation is valid when liquid evaporation occurs in vacuum. When liquid vaporizes in real conditions it is necessary to take into account the non-isothermic nature of the process and the diffusion of vapors into the atmosphere, as well as the possible entrainment of vapors by convective air flows. After the appropriate corrections as a result of special tests there was obtained the equation for determining the evaporation rate. Variants of emergency spillage of fire-hazardous liquids are considered depending on a combination of the following temperatures: the boiling temperature of the liquid, the flash temperature of the liquid, the temperature of the liquid before the spill and the ambient temperature. Equations for calculating the evaporation intensity are defined for every variant. There is carried out correlation of the variants with liquid evaporation during emergency spill with the classification of liquids according to the state diagram in relation to the range of ambient temperatures according to Marshall.

A Theoretical and Experimental Study of the Vibratory Behavior of a High-Precision Optical Positioning Table

1997 ◽  
Author(s):  
Ipek Basdogan ◽  
Thomas J. Royston ◽  
Juan Barraza ◽  
Deming Shu ◽  
Tuncer M. Kuzay
Keyword(s):  
High Precision ◽  
Dynamic Properties ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Theoretical Models ◽  
Positioning Systems ◽  
Wide Range ◽  
Optical Table ◽  
The Individual ◽  
Optical Positioning

Abstract At the Advanced Photon Source (APS), a state-of-the-art synchrotron radiation facility at Argonne National Laboratory (ANL), high-precision optical positioning systems are needed to conduct a wide range of experiments utilizing the high-brilliance x-ray beam. The high-precision, multi-dimensional positioning capability required for these positioning systems may be compromised by vibratory motion. The vibratory dynamics of the complex kinematic joints and components that comprise these multibody structures are not easily described by simple theoretical models. A combined experimental and theoretical approach has been developed to predict the dynamic properties of the individual components and joints and of the assembled multibody system. A prototypical optical table has been analyzed as an example case.

scholarly journals Dynamics of a Carriage System of Comparator for Calibrating the Line Standards of Length

2015 ◽  
Vol 12 (2) ◽  
pp. 15
Author(s):  
A. Kilikevičius ◽  
V. Vekteris ◽  
V. Mokšin
Keyword(s):  
Mathematical Models ◽  
High Precision ◽  
Dynamic Properties ◽  
Resonant Frequencies ◽  
Frequency Responses ◽  
Calculated Amplitude ◽  
Multi Body ◽  
Body Dynamic

This paper presents research dynamic properties of a calibration comparator which is used to calibrate high precision line standards of length. For this purpose, multi-body dynamic and mathematical models of a carriage system of the comparator were presented. Calculated amplitude-frequency responses and modes of oscillations allowed a determination of resonant frequencies of the system.  

Deep eutectic solvent-based extraction of uranium(vi) from a wide range acidity and subsequent determination by direct loading in thermal ionization mass spectrometry

2021 ◽  
Author(s):  
Raju V. Shah ◽  
Ashok K. Pandey ◽  
K. Sasi Bhushan ◽  
S. Jagadish Kumar ◽  
Radhika M. Rao ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Thermal Ionization Mass Spectrometry ◽  
Deep Eutectic Solvent ◽  
Thermal Ionization ◽  
Ionization Mass Spectrometry ◽  
Ionization Mass ◽  
Subsequent Determination ◽  
Wide Range ◽  
Thermal Ionization Mass

Deep eutectic solvent impregnated membrane capable of the extracting U(vi) from wide acidity range was prepared and employed for the determination of uranium by thermal ionization mass spectrometry.

On effects of non-systematic reflections on weak-beam images of partial dislocations

1991 ◽  
Vol 49 ◽  
pp. 688-689
Author(s):  
K. Z. Botros ◽  
S. S. Sheinin
Keyword(s):  
High Precision ◽  
Stacking Fault ◽  
Important Application ◽  
Stacking Fault Energy ◽  
Sharp Peak ◽  
Weak Beam ◽  
Partial Dislocations ◽  
Deviation Parameter ◽  
Beam Diffraction

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.

Automation of selected brazes' dynamic properties in high-temperatures' measurement process

2013 ◽  
Vol 18 (2-3) ◽  
pp. 33-41
Author(s):  
Dominik Sankowski ◽  
Marcin Bakala ◽  
Rafał Wojciechowski
Keyword(s):  
Surface Tension ◽  
High Temperatures ◽  
Dynamic Properties ◽  
Automatic Measurement ◽  
Measurement Methodology ◽  
Joining Process ◽  
Wetting Force ◽  
Research Grant

Abstract The good quality of several manufactured components frequently depends on solidliquid interactions existing during processing. Nowadays, the research in material engineering focuses also on modern, automatic measurement methods of joining process properties, i.a. wetting force and surface tension, which allows for quantitative determination of above mentioned parameters. In the paper, the brazes’ dynamic properties in high-temperatures’ measurement methodology and the stand for automatic determination of braze’s properties, constructed and implmented within the research grant nr KBN N N519 441 839 - An integrated platform for automatic measurement of wettability and surface tension of solders at high temperatures, are widely described

Sorption of Se (IV) from aqueous solutions with subsequent determination by X-ray fluorescence analysis

2020 ◽  
Vol 86 (10) ◽  
pp. 5-9
Author(s):  
D. G. Filatova ◽  
A. A. Arkhipenko ◽  
M. A. Statkus ◽  
V. V. Es’kina ◽  
V. B. Baranovskaya ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Fluorescence Analysis ◽  
Standard Samples ◽  
Phase Contact Time ◽  
Sorbent Phase ◽  
X Ray ◽  
Fundamental Parameters ◽  
Inductively Coupled ◽  
Subsequent Determination

An approach to sorptive separation of Se (IV) from solutions on a novel S,N-containing sorbent with subsequent determination of the analyte in the sorbent phase by micro-x-ray fluorescence method is presented. The sorbent copolymethylenesulfide-N-alkyl-methylenamine (CMA) was synthesized using «snake in the cage» procedure and proven to be stable in acid solutions. Conditions for quantitative extraction of Se (IV) were determined: sorption in 5 M HCl or 0.05 M HNO3 solutions when heated to 60°C, phase contact time being 1 h. The residual selenium content in the solution was determined by inductively coupled plasma mass spectrometry (ICP-MS) using 82Se isotope. The absence of selenium losses is proved and the mechanism of sorption interaction under specified conditions is proposed. The method of micro-x-ray fluorescence analysis (micro-RFA) with mapping revealed a uniform distribution of selenium on the sorbent surface. The possibility of determining selenium in the sorbent phase by micro-RFA is shown. When comparing the obtained results with the results of calculations by the method of fundamental parameters, it is shown the necessity of using standard samples of sorbates to obtain correct results of RFA determination of selenium in the sorbent phase.

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