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Tytuł:
Review of computer codes for modeling corrosion product transport and activity build-up in light water reactors
Autorzy:
Rafique, M.
Mirza, N. M.
Mirza, S. M.
Iqbal, M. J.
Powiązania:
https://bibliotekanauki.pl/articles/148648.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
corrosion product
light water reactors
fuel cladding
radiation field
Opis:
The corrosion products are among the leading sources of radiation in primary coolant circuits of pressurized water reactors leading to prolongation of reactor down-time for routine maintenance entailing substantial loss of revenues. These deposits affect adversely coolant flow rates resulting in elevation of fuel and cladding temperature and become activated by high neutron flux in reactor core consequently creating high radiation field by accumulating in the out-of-core reactor components. In the case of light water reactors (LWRs), prevailing corrosion products include 59Fe, 99Mo, 56Mn, 58Co, and 60Co. The 56Mn is the leading corrosion product activity source during operation while cobalt isotopes dominate the activity after reactor shutdown. This paper presents a detailed discussion on some computer codes developed for prediction and transport of corrosion product activity in LWRs.
Źródło:
Nukleonika; 2010, 55, 3; 263-269
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on dose correction method of vehicle-borne environmental radiation measurement equipment
Autorzy:
Xu, Jie
Ren, Jizhou
Yang, Jianbo
Fan, Jiawen
Li, Rui
Li, Hui
Huang, Weiqi
Yuan, Biao
Powiązania:
https://bibliotekanauki.pl/articles/2055679.pdf
Data publikacji:
2021
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
dose correction factor
reference radiation field
vehicle-borne environmental radiation measurement equipment
Opis:
This study establishes a near-ground reference radiation field based on typical radionuclides of the Fukushima accident in response to the need for vehicle-borne environmental radiation measurement equipment that can accurately evaluate the environmental dose of nuclear accidents. The Monte Carlo code FLUKA is used to study the environmental dose of such equipment in the early and mid-late reference radiation fields of nuclear accidents. Results of the air dose rate at 1 m above the ground were corrected to eliminate data difference between diverse measurement platforms. Simulation results show that t he dose correction factor (CF) fluctuates at approximately 0.8813 in the early reference radiation field and at approximately 0.6711 in the mid-late reference radiation field . This deviation of the dose CF in the early and mid-late reference radiation field s is within 2% and is not affected by the change in detector position. This research can be applied to obtain more accurate measurement of an ambient dose in the near-ground radiation field and support the vehicle-borne environmental radiation measurement technology.
Źródło:
Nukleonika; 2021, 66, 3; 103--110
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of DC permanent magnet disc motor and improving its EMC
Autorzy:
Kovacova, I.
Kanuch, J.
Kovac, D.
Powiązania:
https://bibliotekanauki.pl/articles/262741.pdf
Data publikacji:
2005
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Tematy:
electromagnetic compatibility
disc motor
electromagnetic field radiation
Opis:
The paper deals with construction design of DC permanent magnet disc motor by classical calculation method and its verifying by computer finite element simulation method. The paper deals also with the computer analysis of the electromagnetic compatibility (EMC) problems focused to the area of electrical machines, which can also disclose the startling facts concerning. A problem of interference between electric motor and surroundings space caused by electromagnetic field radiation is discussed too.
Źródło:
Electrical Power Quality and Utilisation. Journal; 2005, 11, 2; 23-39
1896-4672
Pojawia się w:
Electrical Power Quality and Utilisation. Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kontrola i kształtowanie warunków pracy w polach i promieniowaniu elektromagnetycznym. Zakres częstotliwości od O Hz do 300 GHz
Principles of controlling and shaping working conditions in electromagnetic fields and radiation in the frequency range from0Hz to300GHz
Autorzy:
Karpowicz, J.
Gryz, K.
Powiązania:
https://bibliotekanauki.pl/articles/180772.pdf
Data publikacji:
2001
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
pole elektromagnetyczne
promieniowanie elektromagnetyczne
warunki pracy
narażenie zawodowe
electromagnetic field
electromagnetic field radiation
work conditions
occupational exposure
Opis:
W artykule omówiono nowelizację i ujednolicenie zasad ograniczania ekspozycji zawodowej w polach elektromagnetycznych z pasma od 0 Hz do 300 GHz, które weszły do stosowania 23 lipca (Dz. U. nr 4/2001, poz. 36). Wartości najwyższych dopuszczalnych natężeń (NDN) oparto na wynikach analizy dotychczas obowiązujących polskich przepisów (ustanawianych od 1972 r.), zaleceń międzynarodowych, projektów norm europejskich, przeglądu światowej literatury dotyczącej efektów biologicznych i zdrowotnych związanych z ekspozycją na pola elektromagnetyczne oraz wynikach badań krajowych.
The article discusses an amendment and unification of the principles of limiting occupational exposure to electromagnetic fields (EMF) in the range from O Hz to 300 GHz, which came into force on July 23 (DzU, 4/2001, item 36). The Maximal Admissible Intensity values were based on the results of an analysis of previous Polish regulations (established since 1972), international recommendations, drafts of European standards and a survey of the world literature on the biological effects of EMF and on the health effects of exposure to EMF and on the results of Polish research.
Źródło:
Bezpieczeństwo Pracy : nauka i praktyka; 2001, 10; 7-13
0137-7043
Pojawia się w:
Bezpieczeństwo Pracy : nauka i praktyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Full-wave Analysis of Periodic Baffle System in Beamforming Applications
Autorzy:
Tasinkevych, Y.
Danicki, E.
Powiązania:
https://bibliotekanauki.pl/articles/177861.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
sound field calculation
linear phased arrays
BIS expansion
far-field radiation pattern
beam-steering
transducer arrays
composite transducers
scattering
generation
fields
Opis:
Mixed boundary-value problem for periodic baffles in acoustic medium is solved with help of the method developed earlier in electrostatics. The nice feature of the method is that the resulting matrices are relatively easy for computations and that the results satisfy exactly the energy conservation law. Illustrative numerical examples present the wave-beam steering (in the far-field) in a baffle system that may be considered as a model of one-dimensional ultrasonic transducer array.
Źródło:
Archives of Acoustics; 2010, 35, 4; 661-675
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distributed radiation monitoring system for linear accelerators based on CAN bus
Autorzy:
Kozak, T.
Makowski, D.
Napieralski, A.
Powiązania:
https://bibliotekanauki.pl/articles/397933.pdf
Data publikacji:
2010
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
obszar pod kontrolą sieci
dozymetria promieniowania gamma
dozymetria promieniowania neutronowego
akcelerator liniowy
controller area network
gamma radiation dosimetry
neutron radiation dosimetry
radiation sensing Field Effect Transistor
linear accelerator
X-ray free electron laser
Opis:
Gamma and neutron radiation is produced during the normal operation of linear accelerators like Free-Electron Laser in Hamburg (FLASH) or X-ray Free Electron Laser (X-FEL). Gamma radiation cause general degeneration of electronics devices and neutron fluence can be a reason of soft error in memories and microcontrollers. X-FEL accelerator will be built only in one tunnel, therefore most of electronic control systems will be placed in radiation environment. Exposing control systems to radiation may lead to many errors and unexpected failure of the whole accelerator system. Thus, the radiation monitoring system able to monitor radiation doses produced near controlling systems is crucial. Knowledge of produced radiation doses allows to detect errors caused by radiation, schedule essential replacement of control systems and prevent accelerator from serious damages. The paper presents the project of radiation monitoring system able to monitor radiation environment in real time.
Źródło:
International Journal of Microelectronics and Computer Science; 2010, 1, 1; 52-55
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ambient fields generated by a laser spark
Autorzy:
Rohlena, K.
Mašek, M.
Powiązania:
https://bibliotekanauki.pl/articles/148063.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
laser spark
radiation chemistry
field generation
Opis:
The electric and magnetic fields surrounding a laser spark formed after an optical breakdown due to a focused nanosecond laser beam in a gaseous environment are examined in order to assess their possible influence on the processes going on in the gas medium, mainly chemical reactions triggered by the spark plasma radiation. The magnetic field is generated by the standard mechanism of crossed electron density and temperature gradients, the electric field is supposed to be produced by the plasma polarization due to its radial expansion across the self-generated magnetic field. A simple model of spark plasma formation near the tip of the focal cone is assumed, with a delayed breakdown, which allows the focused laser light to sweep the whole volume of the forming spark right down to the focal caustic and thus to form a centimeter long plasma cone. In this conical geometry, the value of plasma electric dipole moment is evaluated as a measurable quantity as well as approximate values of the electric and magnetic field near the focal caustic, where they both tend to grow in magnitude.
Źródło:
Nukleonika; 2016, 61, 2; 119-124
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electromagnetic fields and electromagnetic radiation as non-invasive external stimulants for seeds [selected methods and responses]
Autorzy:
Pietruszewski, S.
Muszynski, S.
Dziwulska, A.
Powiązania:
https://bibliotekanauki.pl/articles/24466.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
laser radiation
electromagnetic field
seedling
pre-sowing stimulation
electromagnetic radiation
seed
Źródło:
International Agrophysics; 2007, 21, 1
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Low-Frequency Noise Attenuation in a Closed Space Using Adaptive Directivity Control Sources of a Quadrupole Type
Autorzy:
Giouvanakis, Marios
Sevastiadis, Christos
Papanikolaou, George
Powiązania:
https://bibliotekanauki.pl/articles/176748.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
modal field
noise control
adaptive radiation sources
Opis:
A novel method of active noise control using adaptive radiation sound sources is investigated. A finite element model of a modal enclosed sound field is excited harmonically, representing a noise field in the low-frequency range. The control sources are comprised of elementary dipole sources for which the driving signals are adjusted by an optimization method. Two set-up cases of the proposed compound sources are investigated. The coupling of the control sources with the modal sound field is discussed. The simulated performance of the proposed method is compared with that of a system with distributed simple sources and the results show the effectiveness of the sources with adaptive radiation for active noise control in small enclosures.
Źródło:
Archives of Acoustics; 2019, 44, 1; 71-78
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyki wybranych źródeł niezamierzonego promieniowania elektromagnetycznego
Characteristics of selected unfolded sources electromagnetic radiation
Autorzy:
Paś, J.
Powiązania:
https://bibliotekanauki.pl/articles/309782.pdf
Data publikacji:
2017
Wydawca:
Instytut Naukowo-Wydawniczy "SPATIUM"
Tematy:
pole elektromagnetyczne
promieniowanie
indukcja
electromagnetic field
radiation
induction
Opis:
W artykule przedstawiono wybrane charakterystyki promieniowania niezamierzonych źródeł pola elektromagnetycznego z zakresu małych częstotliwości. Przedstawiono metodykę pomiaru poszczególnych składowych pola elektromagnetycznego – natężenia E pola elektrycznego i indukcji B pola magnetycznego. W artykule zaprezentowano przykładowe wyniki badań dla wybranych źródeł pola elektromagnetycznego oraz przeprowadzono analizę otrzymanych wyników według obowiązujących unormowań prawnych.
The article presents selected radiation characteristics of unintended sources of low frequency electromagnetic field. The methodology for measuring the individual components of the electromagnetic field - E of electric field and induction B of magnetic field - was presented. The article presents examples of research results for selected sources of electromagnetic field and analysis of obtained results according to current legal regulations.
Źródło:
Autobusy : technika, eksploatacja, systemy transportowe; 2017, 18, 12; 1204-1207, CD
1509-5878
2450-7725
Pojawia się w:
Autobusy : technika, eksploatacja, systemy transportowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-band coaxial monopole antenna with an additional metal screen
Autorzy:
Khruslov, M.
Pazynin, V.
Powiązania:
https://bibliotekanauki.pl/articles/307620.pdf
Data publikacji:
2007
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
monopole antenna
near field
radiation pattern
FDTD technique
Opis:
The novel coaxial monopole antenna design with an additional metal screen is presented. The radiation char- acteristics of this antenna are investigated depending on a dis- tance between the ground plane and additional metal screens, as well as on a size of the latter. Measured and calculated ra- diation patterns are compared within limits of the operative frequency band and their revealed distinctions are discussed. The antennas characteristics allow pronounce that it can be considered as a promising candidate for various practical ap- plications both a single radiator and a composite element of antenna arrays.
Źródło:
Journal of Telecommunications and Information Technology; 2007, 1; 30-34
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Laminar mixed convection flow from a vertical surface with induced magnetic field and convective boundary
Autorzy:
Chaudhary, K.
Sharma, A.
Jha, A. K.
Powiązania:
https://bibliotekanauki.pl/articles/264352.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
promieniowanie cieplne
absorpcja promieniowania
pole magnetyczne
thermal radiation
radiation absorption
convective boundary
induced magnetic field
Opis:
The objective of this investigation is to study the influence of thermal radiation and radiation absorption parameter on a mixed convection flow over a continuously moving porous vertical plate under the action of transverse applied magnetic field taking into account the induced magnetic field with convective boundary. Under certain assumptions, the solutions for the velocity field, temperature distribution and induced magnetic field are obtained. The influences of various parameters on the velocity, temperature fields and on induced magnetic fields are studied graphically. It is also found that the dimensionless Prandtl number, Grashof number, Schmidt number and magnetic parameter have an appreciable influence on the independent variables.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 2; 307-326
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Penetrative convection due to absorption of radiation in a magnetic nanofluid saturated porous layer
Autorzy:
Mahajan, Amit
Sharma, Mahesh Kumar
Powiązania:
https://bibliotekanauki.pl/articles/178577.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
magnetic nanofluids
penetrative convection
Darcy model
radiation absorption
magnetic field
Opis:
The present study investigates the onset of penetrative convection induced by selective absorption of radiation in a magnetic nanofluid saturated porous medium. The influence of Brownian motion, thermophoresis, and magnetophoresis on magnetic nanofluid treatment is taken into consideration. The Darcy’s model is selected for the porous medium. We conduct a linear stability analysis to examine the onset of instability and evaluate the results for two different configurations, namely, when the layer is heated from below and when the layer is heated from above. The numerical investigations are carried out by applying the Chebyshev pseudospectral method. The effect of the porosity parameter E, parameter Y (represents the ratio of internal heating to boundary heating), Lewis number Le, concentration Rayleigh number Rn, Langevin parameter αL, width of nanofluid layer d, diffusivity ratio η, and modified diffusivity ratio NA is examined at the onset of convection. The results indicate that the convection commences easily with an increase in the value of Y, Le, and NA but opposite in the case with a decrease in the value of E, αL, η and d for both the two configurations. The parameter Rn advances the onset of convection when the layer is heated from below, while delays the onset of convection when the layer is heated from above.
Źródło:
Studia Geotechnica et Mechanica; 2019, 41, 3; 129-142
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Size of Source Effect on Accuracy of LWIR Radiation Thermometers
Autorzy:
Cywiak, D.
Cárdenas-García, D.
Rodriguez-Arteaga, H.
Powiązania:
https://bibliotekanauki.pl/articles/221785.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
size of source effect
radiation thermometer
temperature
field of view
Opis:
Determining the size of source effect of a radiation thermometer is not an easy task and manufacturers of these thermometers usually do not indicate the deviation to the measured temperature due to this effect. It is one of the main uncertainty components when measuring with a radiation thermometer and it may lead to erroneous estimation of the actual temperature of the measured target. We present an empiric model to estimate the magnitude of deviation of the measured temperature with a long-wavelength infrared radiation thermometer due to the size of source effect. The deviation is calculated as a function of the field of view of the thermometer and the diameter of the radiating source. For thermometers whose field of view size at 90% power is approximately equal to the diameter of the radiating source, it was found that this effect may lead to deviations of the measured temperature of up to 6% at 200ºC and up to 14% at 500ºC. Calculations of the temperature deviation with the proposed model are performed as a function of temperature and as a function of the first order component of electrical signal.
Źródło:
Metrology and Measurement Systems; 2016, 23, 4; 661-667
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Protection against high-frequency radiation of aviation electronic support systems used in air transport
Autorzy:
Dzunda, M.
Cekanova, D.
Cobirka, L.
Zak, P.
Dzurovcin, P.
Powiązania:
https://bibliotekanauki.pl/articles/116582.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
air transport
aviation electronic support systems
high-frequency radiation
radiation
electromagnetic radiation
arport radars
air electronic safety technology
radar electric field
Opis:
The aim of the article is to analyze the impact of electromagnetic radiation of aviation electronic support systems on environmental segments and a human organism. We were looking for effects of electromagnetic radiation on inhabitants and environment in the vicinity of airport radars. We accomplished measuring and found out the level of radiation harmfulness of electromagnetic radiation sources. In the conclusion we suggest to eliminate the negative impact of electromagnetic radiation on the human organism. At the same time we present the ways how workers, performing their jobs in the vicinity of strong electromagnetic radiation source, can protect themselves in compliance with legislative of the Slovak Republic. We have proposed some possibilities of protection for workers who work close to a strong source of electromagnetic radiation.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2018, 12, 1; 183-186
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unsteady mixed convection nonlinear radiative Casson nanofluid flow with convective boundary condition, heat source and inclined magnetic field effects
Autorzy:
Unyong, Bundit
Govindaraju, Mathialagan
Gunasekaran, Nallappan
Vadivel, Rajarathinam
Powiązania:
https://bibliotekanauki.pl/articles/2141509.pdf
Data publikacji:
2021
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
Casson nanofluid
inclined magnetic field
convective boundary conditions
nonlinear thermal radiation
Opis:
In this paper, we have studied the effect of heat source/sink on unsteady Casson nanofluid past a stretching surface with mixed convection inclined magnetic field and nonlinear thermal radiation numerically. Brownian and thermophoresis effects are studied in this nanofluid model (Buongiorno’s). The governing momentum, energy, and concentration equations are PDEs that are changed into ordinary differential equations by means of suitable transformations. The fourth-order R-K method with shooting technique is adapted to yield the results of this work. The velocity, thermal, and concentration profiles are discussed with the several physical parameters. Also, skin friction, the Nusselt number, and the Sherwood number are examined with the help of the table. It is found that the enhancing value of the unsteady parameter and heat sink parameters reduce the fluid temperature, and the enhancing value of the Casson parameter and heat source parameters increase the fluid temperature. The increasing value of the inclined magnetic field parameter enhances the thermal boundary layer thickness.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2021, 20, 3; 65-76
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation effects on MHD flow past an impulsively started infinite vertical plate with mass diffusion
Autorzy:
Chandrakala, P.
Narayana Bhaskar, P.
Powiązania:
https://bibliotekanauki.pl/articles/955319.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
promieniowanie
pole magnetyczne
płyta pionowa
radiation
magnetic field
vertical plate
finite differences
Opis:
The effects of thermal radiation on a flow past an impulsively started infinite vertical plate in the presence of a magnetic field have been studied. The fluid considered is a gray, absorbing-emitting radiation but non-scattering medium. The dimensionless governing equations are solved by an efficient, more accurate, unconditionally stable and fast converging implicit scheme. The effects of velocity and temperature for different parameters such as the thermal radiation, magnetic field, Schmidt number, thermal Grashof number and mass Grashof number are studied. It is observed that the velocity decreases in the presence of thermal radiation or a magnetic field.
Źródło:
International Journal of Applied Mechanics and Engineering; 2014, 19, 1; 17-26
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation for Acoustic Radiation Force from Rectangular Weakly Focusing Transducer Using the Ray Acoustic Model
Autorzy:
Yu, Lili
Qiao, Shuchang
Shou, Wende
Li, Junhua
Powiązania:
https://bibliotekanauki.pl/articles/2141691.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
radiation force calculation
ray acoustic model
rectangular weakly focusing transducer
far-field integration
Opis:
Based on the ray acoustic model, a new relationship between the radiation force and the acoustic power is studied for a rectangular weakly focusing transducer. The effect of pressure reflection coefficient on this model is discussed. For a totally absorbing target, an approximate closed-form expression is also derived and the performance of this model is compared with that of the far-field integration model. The numerical results show that the agreement is excellent with these two models, which can be both used for correction of measured results, but the formula based on the ray acoustic model can be applied more widely in practice because of its simpler expression. The experimental results show further the effectiveness of the relationship between radiation force and acoustic power for rectangular weakly focusing transducer based on the ray acoustic model. The results presented in this paper are important for application of ultrasound transducers in therapy.
Źródło:
Archives of Acoustics; 2022, 47, 1; 81-88
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Environment Conditions on Ultrasonic and Electrostatic Precipitation of Aerosols of Wood Flour
Autorzy:
Stepkina, Maria
Kudryashova, Olga
Antonnikova, Alexandra
Powiązania:
https://bibliotekanauki.pl/articles/177035.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
dispersive medium
relative humidity
temperature
ultrasonic radiation
electrostatic field
finely-dispersed aerosol particles
Opis:
The risk of human exposure to finely-dispersed aerosol particles being airborne indoors is determined by the size and the number concentration of particles, the intensity of an aerosol emission source, the air filtration and ventilation efficiency, etc. The emphasis in this article is on behaviour patterns of aerosol particles when exposed to ultrasonic and electrostatic fields in different conditions of air temperature and relative humidity. Wood flour having sizes of interest (characteristic particle diameter about 10 μm) is chosen as a model aerosol. The article considers a physical and mathematical model presenting the evolution of aerosol particles in external fields, taking into account the moisture content and the temperature of a dispersive medium. The efficiency of ultrasonic and electrostatic precipitation in different relative humidity and temperature conditions in an enclosed space was studied using optical measurement methods of particle size and concentration.
Źródło:
Archives of Acoustics; 2020, 45, 1; 29-34
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ethological Changes and Teratogenesis of Model Organisms as an Indicator of Biotesting of the Electromagnetic Radiation Influence
Autorzy:
Wójcik, Waldemar
Kalizhanova, Aliya
Sakun, Oksana A.
Nykyforov, Volodymyr V.
Nykyforova, Larysa E.
Nahorniak, Svitlana V.
Kistion, Volodymyr Ev.
Shevchenko, Liudmyla S.
Yesmakhanova, Laura
Junisbekov, Mukhtar
Orazbekov, Zhaslan
Turgantarova, Aigul
Powiązania:
https://bibliotekanauki.pl/articles/2173307.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
biotesting
ecological safety
electromagnetic radiation
magnetic field
model organism
activity level
teratogenesis
mortality
Opis:
With the development of information technology, electromagnetic radiation becomes a tangible view of the physical (wave) environmental pollution. Modern scientific research aimed at the components of the elec tromagnetic environment pollution problems mainly involves the anthropocentric approach. There is no procedure for determining the influence of harmful physical factors on biota, in particular in terms of water (Daphnia magna Straus) and air (Drosophila melanogaster L.) environments. A clear system of rationing of maximum permissible levels of electromagnetic radiation, including volume and ecosystems protected areas has not been developed. The article considers the relevant scientific and practical problem of creating a framework for assessing and predicting the negative impact of electromagnetic radiation on the biota related to ethological changes and teratogenesis. The characteristic of all the constituent elements of the system determines the degree of the negative impact of the induction of the magnetic field on the biota: activity, mortality; reproduction; availability, and frequency of Teratology. A method for determining the activity levels of Daphnia and Drosophila total average activity biota was developed and described. The trajectory patterns of Daphnia motion at low activity in the state of stability, with increased activity in the excited state, were created. The results of the research on the negative impact of electromagnetic radiation of industrial frequency on biota were presented. The critical levels of the magnetic field and noise pollution, which cause the depletion and destruction of the test object, the relationship between ethological changes and the occurrence of mutations depending on radiation levels were determined. The biological test objects were proven to minimize the error of the results of determination of electromagnetic effects on the biota, in comparison with the mathematical methods of research.
Źródło:
Journal of Ecological Engineering; 2022, 23, 7; 42--49
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Profilaktyka zagrożeń elektromagnetycznych - symulacje komputerowe i badanie osłon ekranujących
Prevention of electromagnetic hazards - numerical simulations and an experimental study
Autorzy:
Zradziński, P.
Gryz, K.
Karpowicz, J.
Molenda, M.
Powiązania:
https://bibliotekanauki.pl/articles/179819.pdf
Data publikacji:
2003
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
promieniowanie elektromagnetyczne
osłony ekranujące
zagrożenia elektromagnetyczne
pole elektromagnetyczne
electromagnetic radiation
electromagnetic hazard
electromagnetic field
Opis:
Ekranowanie elektromagnetyczne jest jedną z bardziej skutecznych metod technicznych ograniczania zagrożeń elektromagnetycznych w środowisku pracy. W artykule omówiono metody ograniczania zagrożeń oraz zaprezentowano możliwości stosowania symulacji numerycznych, na przykładzie obliczeń i pomiarów parametrów prostych ekranów wykonanych z różnych materiałów. W podsumowaniu stwierdzono, że symulacje numeryczne mogą być wygodnym narzędziem doboru i projektowania właściwych rozwiązań osłon ekranujących.
Electromagnetic shielding is one of the more effective technical methods of reducing electromagnetic hazards in the working environment. Methods of hazards reduction are discussed and the possibility of using numerical simulations is presented, with sample calculations and measurements of characteristics of simple shields made from different materials. Numerical calculations can be a convenient tool for selecting and designing suitable shields.
Źródło:
Bezpieczeństwo Pracy : nauka i praktyka; 2003, 10; 27-31
0137-7043
Pojawia się w:
Bezpieczeństwo Pracy : nauka i praktyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Profilaktyka i ochrona zdrowia personelu wojskowego zatrudnionego w zasięgu promieniowania elektromagnetycznego w świetle najnowszych uregulowań prawnych resortu obrony narodowej
The prevention and health care requirements for the military personnel employed at the electromagnetic radiation exposure area in the light of the newest legal framework of the Ministry of Defense
Autorzy:
Sobiczewska, E.
Stankiewicz, W.
Kieliszek, J.
Powiązania:
https://bibliotekanauki.pl/articles/179012.pdf
Data publikacji:
2013
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
pole elektromagnetyczne
personel wojskowy
ochrona przed promieniowaniem EM
zasięg promieniowania
narażenie
electromagnetic field
military personnel
protection against electromagnetic radiation
radiation range
exposure
Opis:
Pole elektromagnetyczne jest jednym z istotnych czynników występujących na stanowiskach pracy w jednostkach organizacyjnych resortu obrony narodowej. Specyfika pracy personelu wojskowego w zasięgu promieniowania elektromagnetycznego ze względu na rodzaj stosowanych urządzeń, często utrudnia zastosowanie krajowych przepisów bezpieczeństwa i higieny pracy. W celu pełnej ochrony zdrowia personelu wojskowego i zapewnienia bezpieczeństwa pracy w Zakładzie Ochrony Mikrofalowej Wojskowego Instytutu Higieny i Epidemiologii opracowano projekt normy „Bezpieczeństwo i higiena pracy. Ochrona przed promieniowaniem elektromagnetycznym. Profilaktyka i ochrona zdrowia personelu zatrudnionego w zasięgu promieniowania elektromagnetycznego od 0 Hz do 300 GHz”. W artykule omówiono określone w normie wymagania dotyczące profilaktyki i ochrony zdrowia personelu wojskowego zatrudnionego w zasięgu promieniowania elektromagnetycznego, wymagania w zakresie oszacowania narażenia personelu na promieniowanie elektromagnetyczne według skali względnej dla potrzeb profilaktyki i ochrony zdrowia personelu, a także zasady postępowania w wydarzeniach wypadkowych związanych z promieniowaniem elektromagnetycznym.
The electromagnetic field ( the electromagnetic radiation) is one of the most essential factors, which exist at the workplace at the organizational units of the Ministry of National Defence. The specificity of work of the military personnel, within the electromagnetic radiation range, often impedes an application of the civil National Safety and Health at Work regulations. For the complete protection of health of the military personnel and assurance of work safety in the Department of Microwave Safety, at the Military Institute of Hygiene and Epidemiology was formulated the proposal of standard: “Occupational safety and health. Protection against electromagnetic radiation. Prophylaxis and health protection of personnel working at the range 0 Hz to 300 GHz of electromagnetic radiation”. The article presents specified in the standard the prevention and health care requirements for the military personnel, who is employed at the electromagnetic radiation exposure area, estimation of risk of the electromagnetic radiation exposure by a relative scale for the prevention and health purposes and the code of actions after accidents which may occur in the electromagnetic field area.
Źródło:
Bezpieczeństwo Pracy : nauka i praktyka; 2013, 9; 10-12
0137-7043
Pojawia się w:
Bezpieczeństwo Pracy : nauka i praktyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena przydatności metod fizycznych do zwalczania przechowalniczych chorób bulw ziemniaka
Feasibility study of physical methods for treating potato bulb diseases resulting from storage
Autorzy:
Marks, N.
Lipiec, J.
Jakubowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/286534.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Inżynierii Rolniczej
Tematy:
promieniowanie mikrofalowe
pole elektryczne
pole magnetyczne
choroba przechowalnicza
odmiana
ziemniak
microwave radiation
electric field
magnetic field
diseases resulting from storage
species
potato
Opis:
W pracy dokonano oceny przydatności wybranych metod fizycznych do zwalczania przechowalniczych chorób bulw ziemniaka jak rizoktonioza i parch zwykły. Badania prowadzono w latach 2002 – 2004 na trzech odmianach ziemniaków: Salto, Drop i Irga. Poddanie bulwy ziemniaka działaniu impulsowego pola elektrycznego, ekspozycji na działanie pola magnetycznego czy stosowanie promieni mikrofalowych redukuje rozwój i populację niektórych bakterii oraz grzybów charakterystycznych dla chorób przechowalniczych ziemniaków. Oceniając wpływ badanych czynników na stopień porażenia bulw rizoktoniozą i parchem zwykłym, stwierdzono pozytywny ich wpływ (poprawę zdrowotności bulw) w przypadku rizoktoniozy i negatywny wpływ w stosunku do kontroli w przypadku parcha zwykłego. Przedstawione rezultaty wskazują na celowość dalszych badań w tym zakresie.
The paper provides a feasibility study of selected physical methods for treating potato bulb diseases resulting from storage, such as rhizoctonia and common scab. The study was carried out between 2002 and 2004 on three potato species: Salto, Drop and Irga. Subjecting a potato bulb to pulsating electric field, exposure to magnetic field and application of microwaves inhibits growth of some bacteria, fungus and development of diseases typical for stored potatoes. While estimating the effect of studied factors on the extent of occurrence of rhizoctonia and common scab in potato bulbs, they have been found positive (improvement in bulb health) in case of rhizoctonia, and negative in relation to control, in case of the common scab. The results demonstrated indicate that it is quite reasonable to further investigate this issue.
Źródło:
Inżynieria Rolnicza; 2005, R. 9, nr 7, 7; 169-175
1429-7264
Pojawia się w:
Inżynieria Rolnicza
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Study on the Effects of Inclined Magnetic Field, Flow Medium Porosity and Thermal Radiation on Free Convection of Casson Nanofluid over a Vertical Plate
Autorzy:
Sobamowo, M. G.
Yinusa, A. A.
Makinde, O. D.
Powiązania:
https://bibliotekanauki.pl/articles/1046549.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Casson nanofluid
Flow medium porosity
Free convection
Inclined magnetic field
Thermal radiation
Variational homotopy perturbation method
Opis:
In this paper, variational homotopy perturbation method with Padé approximant technique is applied to investigate the impacts of inclined magnetic field, flow medium porosity and thermal radiation on free convection flow and heat transfer of Casson nanofluids over a vertical plate. The accuracies of the developed analytical methods are verified by comparing the results of the analytical solutions with the results of past works as presented in literature. Thereafter, the analytical solutions are used to investigate the effects of thermal radiation; Prandtl number, nanoparticles volume-fraction, shape and type on the flow and heat transfer behaviour of various nanofluids over the flat plate. It is observed that both the velocity and temperature of the nanofluid as well viscous and thermal boundary layers increase with increase in the radiation parameter. The velocity and temperature of the nanofluid decreases and increases, respectively as the Prandtl number and volume-fraction of the nanoparticles in the basefluid increase. The maximum decrease in velocity and maximum increase in temperature are caused lamina shaped nanoparticle and followed by platelets, cylinder, bricks and sphere-shaped nanoparticles, respectively. It is hoped that the present study will enhance the understanding of free convection boundary-layer problems under the influence of thermal radiation as applied in various engineering processes.
Źródło:
World Scientific News; 2019, 138, 1; 1-64
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of chemical reaction on transient MHD flow with mass transfer past an impulsively fixed infinite vertical plate in the presence of thermal radiation
Autorzy:
Reddy, B. Prabhakar
Powiązania:
https://bibliotekanauki.pl/articles/264441.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
magnetohydrodynamika
pole magnetyczne
reakcja chemiczna
MHD
magnetic field
fixed vertical plate
chemical reaction parameter
radiation parameter
Opis:
The effects of chemical reaction on a transient MHD mixed convection flow with mass transfer past an impulsively fixed infinite vertical plate under the influence of a transverse magnetic field have been presented. The medium is considered to be non-scattering and the fluid to be non-gray having emitting-absorbing and optically thick radiation limit properties. The dimensionless governing equations of the flow and mass transfer with boundary conditions are solved numerically by using the Ritz finite element method. The numerical results for the velocity, temperature and the concentration profiles as well as the skin-friction coefficient for different values of physical parameters such as the radiation parameter, magnetic parameter, Schmidt number and chemical reaction parameter have been obtained and presented through graphs and tables. It has been found that there is a fall in the temperature and velocity for both air and water as the radiation parameter is increased. An increase in the Schmidt number and chemical reaction parameter results a decrease in the concentration and velocity profiles for both air and water. Furthermore, an increase in the radiation parameter, magnetic parameter, Schmidt number and chemical reaction parameter decreases the skin-friction.
Źródło:
International Journal of Applied Mechanics and Engineering; 2019, 24, 4; 169-182
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 44

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