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Tytuł:
A comparison of the basic photon and electron dosimetry data for Neptun 10PC linear accelerators
Autorzy:
Shokrani, P.
Monadi, S.
Powiązania:
https://bibliotekanauki.pl/articles/147666.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
dosimetry
photon beam
electron beam
linear electron accelerator
Opis:
. In recent years the similarity of dosimetric characteristics of modern linear accelerators with the same make, model and nominal energy, has become more common. The goal of this study was to quantitatively investigate the reproducibility of the basic photon and electron dosimetry data from Neptun 10PC accelerators across the institutions. In the current study, the photon and electron dosimetry data collected during acceptance and initial commissioning of six Neptun 10PC linear accelerators are analyzed. The dates of original installations of these six machines were evenly spread out over a 5 year period and the series of measurements were conducted during an average of 1-2 months after original installations. All units had identical energies and beam modifiers. For photon beams, the collected data include depth dose data, output factors and beam profile data in water. For electron beams, in addition to depth dose data and output factors, the effective source skin distance for 10 × 10 cm field size is also presented. For most beam parameters the variation (one standard deviation), was less than 1.0% (less than 2% for 2 parameters). A variation of this magnitude is expected to be observed during annual calibration of well-maintained accelerators. In conclusion, this study is presenting a consistent set of data for Neptun 10PC linear accelerators. This consistency implies that for this model, a standard data set of basic photon and electron dosimetry could be established, as a guide for future commissioning, beam modeling and quality assurance purposes.
Źródło:
Nukleonika; 2008, 53, 4; 181-185
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Decomposition of toluene in air mixtures under electron beam irradiation
Autorzy:
Sun, Y.
Chmielewski, A. G.
Bułka, S.
Zimek, Z.
Powiązania:
https://bibliotekanauki.pl/articles/148028.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
toluene
4-chlorotoluene
decomposition
electron beam
Opis:
The model gases of toluene-air mixtures were prepared by blowing technical air into liquid toluene and then irradiated with an ILU-6 accelerator located at the Institute of Nuclear Chemistry and Technology (INCT), Poland. It was found that the decomposition efficiency of toluene increases with absorbed dose and decreases with initial concentration of toluene. At 14.5 kGy dose, the decomposition efficiencies of toluene were 50, 37 and 34.5% for the initial concentrations of toluene 32.0, 63.4 and 78.0 ppm, respectively. At 58.0 kGy dose, the decomposition efficiencies of toluene were 93.8 and 78.1%, the initial concentrations of toluene being 32.0 and 63.4 ppm, respectively. Benzaldehyde was identified as one of the by-products of toluene decomposition in an air mixture. The decomposition efficiency and by-product formation under EB irradiation were compared between toluene and 4-chlorotoluene.
Źródło:
Nukleonika; 2009, 54, 2; 65-70
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On possible formulation of problems of a Dense Plasma Focus used in material sciences
Autorzy:
Gribkov, V.
Powiązania:
https://bibliotekanauki.pl/articles/146787.pdf
Data publikacji:
2000
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
cumulative plasma streams
dense plasma focus (DPF)
electron beam
ion beam
material sciences
neutrons
X-rays
Opis:
The paper describes various possibilities at can be given by the use of dense plasma focus (DPF) device in material sciences. Main distinguishing features of such a device – availability of several different types of hard radiation and its high power flux density – determine the niche of applications of this type devices in the field. Some directions of materials investigation and treatment, which can be developed at present time, are discussed.
Źródło:
Nukleonika; 2000, 45, 3; 149-153
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computer-simulated degradation of CF3Cl, CF2Cl2, and CFCl3 under electron beam irradiation
Autorzy:
Kabasa, Stephen
Sun, Yongxia
Chmielewski, Andrzej G.
Nichipor, Henrietta
Powiązania:
https://bibliotekanauki.pl/articles/24202753.pdf
Data publikacji:
2023
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
chlorofluorocarbons (CFCs)
computer simulation
electron beam
mechanism
Opis:
Electron beam treatment technologies should be versatile in the removal of chlorofl uorocarbons (CFCs) owing to their exceptional cross sections for the thermal electrons generated in the radiolysis of air. Humidity, dose rates, O2 concentration, and CFC concentration infl uence the effi ciency of the destruction process under electron beam treatment. Computer simulations have been used to theoretically demonstrate the destruction of chlorotrifl uoromethane (CF3Cl), dichlorodifl uoromethane (CF2Cl2), and trichlorofl uoromethane (CFCl3) in the air (N2 + O2: 80% + 20%) in room temperature up to a dose of 13 kGy. Under these conditions, it is predicted that the removal effi ciency is in the order CF3Cl (0.1%) < CF2Cl2 (7%) < CFCl3 (34%), which shows the dependence of the process on the number of substituted Cl atoms. Dissociative electron attachment with the release of Cl– is the primary process initiating the destruction of CFCs from the air stream. Reactions with the first excited state of oxygen, namely, O(1 D), and charge-transfer reactions further promote the degradation process. The degradation products can be further degraded to CO2, Cl2, and F2 by prolonged radiation treatment. Other predicted products can also be removed through chemical processes.
Źródło:
Nukleonika; 2023, 68, 3; 67--76
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Combination of methods of thermal and radiation treatment of sediments associated with PCBs : the Delor type
Autorzy:
Fülöp, Marko
Šagátová, Andrea
Benkovský, Ivan
Prokes, Karel
Foltinova, Lubica
Powiązania:
https://bibliotekanauki.pl/articles/2055684.pdf
Data publikacji:
2021
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
electron beam
heat treatment
polychlorinated biphenyls
radiation degradation
Opis:
An efficient method of burning polychlorinated biphenyls (PCBs) is often used to remove the environmental burden of PCBs. However, combustion produces toxic dioxins and furans (PCDD/F), so residents are increasingly rejecting this method. The heat treatment (HT) method does not burn PCBs but evaporates it from sediments. Even in this process, PCDD/Fs are formed to a lesser extent, which are destroyed by radiation processing (RP) following the HT. At the same time, the RP method degrades PCB congeners down to biphenyls, which decompose easily in the environment. A block assembly of a complex synergistic combination of equipment for methods of thermal (HT) and radiation (RP) destruction of PCBs in sediments is proposed. The efficacy of this complex was preliminarily determined at a level of 70-fold reduction in PCB concentration in sediments. To achieve a higher reduction factor in the concentration of PCBs, possible procedures for optimizing the settings of individual devices of this complex are presented.
Źródło:
Nukleonika; 2021, 66, 4; 207--211
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetic modelling of NO heterogeneous radiation-catalytic oxidation on the TiO2 surface in humid air under the electron beam irradiation
Autorzy:
Nichipor, H.
Sun, Y.
Chmielewski, A. G.
Powiązania:
https://bibliotekanauki.pl/articles/148642.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
electron beam
catalyst
reaction kinetics
NOx removal
irradiation
modelling
Opis:
Theoretical study of NOx removal from humid air by a hybrid system (catalyst combined with electron beam) was carried out. The purpose of this work is to study the possibility to decrease energy consumption for NOx removal. The kinetics of radiation catalytic oxidation of NO on the catalyst TiO2 surface under electron beam irradiation was elaborated. Program Scilab 5.3.0 was used for numerical simulations. Influential parameters such as inlet NO concentration, dose, gas flow rate, water concentration and catalyst contents that can affect NOx removal efficiency were studied. The results of calculation show that the removal effiiency of NOx might be increased by 8–16% with the presence of a catalyst in the gas irradiated field.
Źródło:
Nukleonika; 2017, 62, 3; 235-240
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
10 MeV electron beam cross-linking of plasticized PVC in presence of EHPTM and TAC additives
Autorzy:
Behjat, A.
Gheysari, D.
Powiązania:
https://bibliotekanauki.pl/articles/146752.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
plasticized PVC
electron beam
cross-linking
EHPTM
triallylcyanurate (TAC)
Opis:
Irradiation of plasticized PVC (PPVC) compound containing a cross-linking monomer was carried out by a 10 MeV electron beam. This compound mainly is used as insulation in the wire and cable industry. The cross-linking monomers EHPTM and TAC at different ratio of 3, 6, and 9 phr were used. The dose range was varied from 50 to 150 kGy. The effects of monomers and radiation dose on radiation cross-linking were studied by hot-set testing and gel content measurements. In the absence of EHPTM and TAC, cross-linking did not take place by high energy electron beam at any dose and samples had very large elongation in a hot-set apparatus. But in the presence of these monomers, gel content augmented with an increase in radiation dose and EHPTM level. The highest value of approximately 76% gel content was obtained. In this case the lowest hot-set value was about 12%. Also, tensile strength, elongation at break, modulus, volume resistivity, dielectric strength, and limiting oxygen index of samples were examined. It was found that the mechanical properties of samples containing EHPTM and TAC improved significantly with increasing radiation dose. But for PPVC samples loaded with EHPTM, tensile strength values were higher than those of the loaded ones with TAC at all radiation doses. From the hot-set data it is concluded that the samples loaded with EHPTM had a low thermal expansion compared with samples loaded with TAC. The results indicated that EHPTM is a more effective cross-linking agent for PPVC compound compared with TAC.
Źródło:
Nukleonika; 2008, 53, 2; 57-62
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Remediation of polluted waters and wastewater by radiation processing
Autorzy:
Sampa, M. H. O.
Takács, E.
Gehringer, P.
Rela, P. R.
Ramirez, T.
Amro, H.
Trojanowicz, M.
Botelho, M. L.
Han, B.
Solpan, D.
Cooper, W. J.
Emmi, S. S.
Wojnárovits, L.
Powiązania:
https://bibliotekanauki.pl/articles/147644.pdf
Data publikacji:
2007
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
electron beam
wastewater treatment
pesticides
dyes
degradation
radiation technology
Opis:
Application of radiation processing for drinking water, wastewater, and groundwater treatment is a cost effective process which may insure adequate availability of that resource worldwide. This paper summarizes the results of a Coordinated Research Project (organized by the IAEA) with participants from 10 countries with the purpose of describing the degradation mechanism of organic impurities, and establishing optimal treatment conditions. Decoloration, disinfection, microbiological and toxicological experiments are also mentioned. These experiments led to pilot plants and also to a large scale industrial realization of radiation technology.
Źródło:
Nukleonika; 2007, 52, 4; 137-144
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of electron radiation on sugar content in inverted liquid sugar
Autorzy:
Podadera, P.
Sabato, S. F.
Powiązania:
https://bibliotekanauki.pl/articles/148037.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
electron beam
ionizing radiation
inverted liquid sugar
physicochemical properties
Opis:
Inverted liquid sugar is a mixture of sucrose, glucose and fructose, which shows its relevant characteristic on high sweetness power. Ionizing radiation has been applied to different kind of food and ingredients for different reasons, such as pathogens reduction, disinfestations, quarantine purposes, ripening delay among others. Radiation from an electron beam can be utilized as a technique to treat this ingredient because it can process a great volume of material per unit of time. The main goal of this paper was to verify the effect of radiation on the properties of inverted liquid sugar. This ingredient was irradiated in an electron accelerator (Radiation Dynamics) at a dose ranging from 5 to 50 kGy. Sucrose content measurements were reduced by 23% at 30 kGy when compared to control and the reduced sugar content increased around 11%. Density and moisture values were not affected by radiation. The total soluble solids (Brix degrees) rose in function of the absorbed dose.
Źródło:
Nukleonika; 2009, 54, 2; 85-87
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of hindered amine light stabilizers on the resistance of polypropylene towards ionizing radiation
Autorzy:
Przybytniak, G.
Mirkowski, K.
Rafalski, A.
Nowicki, A.
Legocka, I.
Zimek, Z.
Powiązania:
https://bibliotekanauki.pl/articles/148686.pdf
Data publikacji:
2005
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
polypropylene
stabilizers
HALS
electron beam
apparent viscosity
nucleation agent
Opis:
The influence of hindered amine light stabilizers (HALSs) on physical and mechanical properties of irradiated and non-irradiated isotactic polypropylene (PP) was studied. The stabilizers under investigation were: Tinuvin 765 (T765) and Tinuvin 622 (T622) - derivatives of 1,2,2,6,6-pentamethyl piperidine and Chimassorb 944 (C944) - a derivative of 2,2,6,6-tetramethyl piperidine. It was found that the stabilizers reduce the amount of peroxyl radicals in the amorphous phase of PP. The irradiation with electron beam causes a drop of apparent viscosity both in the original and in the modified PP however the effect is smaller in the presence of HALSs. Admixture of T622 and T765 stabilizers increases the crystallization temperature of non-irradiated PP by about 8 10°C (measured by DSC) what results from the facilitated formation of a large number small microcrystals. It was concluded that HALSs initiate two opposite tendencies - chemical protection against damage initiated by free radicals and, simultaneously, physical enhancement of sensitivity towards irradiation by the increase of nucleation density. In the studied systems, the presence of maleic anhydride does not improve compatibility between the polymeric matrix and HALSs.
Źródło:
Nukleonika; 2005, 50, 4; 153-159
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Decomposition of diclofenac in sewage from municipal wastewater treatment plant using ionizing radiation
Autorzy:
Bojanowska-Czajka, Anna
Powiązania:
https://bibliotekanauki.pl/articles/2055688.pdf
Data publikacji:
2021
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
diclofenac
degradation efficiency
electron beam
gamma rays
sewage sludge
Opis:
The decomposition of diclofenac (DCF) in sewage sludge from municipal wastewater treatment plant was investigated. It was found that adsorption of DCF on sludge is about 40%. Compared to previous studies, where the degradation yield in aqueous solution was 100%, in those experiments at the dose up to 5 kGy, only 50% of initial DCF concentration of 50 mg L−1 was decomposed in sediment and in solution over the sediment. The experiments were carried out using both gamma radiation and electron beam. It has been observed that DCF in the aqueous phase, above the sediment, was decomposed with the same efficiency using both gamma radiation and electron beam. Whereas for DCF in the sediment, a higher degradation efficiency was found when gamma radiation was applied. This is most likely due to the limited penetration depth of the electron beam into the sludge layer. It was shown that the applied peroxide addition (in a stoichiometric amount needed for complete mineralization of 50 mg L−1 DCF) did not cause increase in yield of DCF decomposition.
Źródło:
Nukleonika; 2021, 66, 4; 201--206
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation curing: coatings and composites
Autorzy:
Berejka, A. J.
Montoney, D.
Cleland, M. R.
Loiseau, L.
Powiązania:
https://bibliotekanauki.pl/articles/148453.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
radiation curing
fiber composites
coatings
electron beam
X-ray
matrices
Opis:
The initial experiments conducted in the late 1960's at Radiation Dynamics, Inc. (now IBA Industrial, Inc.) showed that by removing the pigment from a radiation curable coating formulation, the same binder system could be used as a matrix system for electron beam (EB) cured fiber reinforced composites. Recently, the binder systems used for EB curable coatings have also been successfully used (without pigments) as the matrices for EB and X-ray cured fiber composites. Insights gained from the development of coatings were translated into desirable properties for matrix materials. For example, understanding the surface wetting characteristics of a coating facilitated the development of a matrix that would wet fibers; the development of coatings that would adhere to rigid substrates as metal while being bent, as for coil coatings, and which would exhibit impact resistance when cured on a metal also imparted impact resistance to cured composite materials. Thermal analyses conducted on the coating binder cured at low energies were consistent with analyses performed on thick cross-sections as used for matrices. The configuration of the final product then dictated the modality of curing, be it low-energy EB for coatings or higher energy EB or X-ray curing for composites. In industrial radiation chemistry, one deals with monomers and oligomers (similar to 102 and similar to 103 to 104 Daltons molecular weight, respectively). Thus, one can approach the development of coating binders or matrix systems as one would approach the synthesis of organic polymers. The desired final material is a fully cured and cross-linked polymer. In contrast, concepts involved in “formulating” are often derived from dealing with high molecular weight polymers (similar to 105 + Daltons) in which intense mechanical mixing is used to bring different ingredients together. When synthesizing a radiation curable coating or matrix system, greater attention is given to microphase compatibility as reflected in the microhomogeneity of the entire material.
Źródło:
Nukleonika; 2010, 55, 1; 97-106
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of boundary effects on electron beam dose distribution formation in multilayer targets
Autorzy:
Kałuska, I.
Lazurik, V. T.
Lazurik, V. M.
Popov, G. F.
Rogov, Y. V.
Zimek, Z.
Powiązania:
https://bibliotekanauki.pl/articles/148556.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
absorbed dose
electron beam
simulation
Monte Carlo
software ModeStEB
dosimetry
Opis:
Computational dosimetry play a significant role in an industrial radiation processing at dose measurements in the product irradiated with electron beams (EB), X-ray and gamma ray from radionuclide sources. Accurate and validated programs for absorbed dose calculations are required for computational dosimetry. The program ModeStEB (modelling of EB processing in a three-dimensional (3D) multilayer flat targets) was designed specially for simulation and optimization of industrial radiation processing, calculation of the 3D absorbed dose distribution within multilayer packages. The package is irradiated with scanned EB on an industrial radiation facility that is based on the pulsed or continuous type of electron accelerators in the electron energy range from 0.1 to 25 MeV. Simulation of EB dose distributions in the multilayer targets was accomplished using the Monte Carlo (MC) method. Experimental verification of MC simulation prediction for EB dose distribution formation in a stack of plates interleaved with polyvinylchloride (PVC) dosimetric films (DF), within a packing box, and irradiated with a scanned 10 MeV EB on a moving conveyer is discussed.
Źródło:
Nukleonika; 2010, 55, 3; 363-368
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bone powder as EPR dosimetry system for electron and gamma radiation
Autorzy:
Ziaie, F.
Hajiloo, N.
Fathollahi, H.
Mehtieva, S. I.
Powiązania:
https://bibliotekanauki.pl/articles/148156.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
bone powder dosimeter
EPR response
dose rate
electron beam
gamma ray
Opis:
In this work bovine bone powder samples were irradiated at three different dose rates of 100, 260 and 630 kGy/min for the absorbed dose range of 3 to 110 kGy, using 10 MeV electron beam radiation. The samples were subjected to EPR measurement at room temperature in air. The variation of EPR signal intensities were constructed and evaluated base on quantitative data related to the absorbed doses. Moreover, they were compared with the obtained results from the samples irradiated by a 60Co gamma-ray source with a dose rate of 2.65 kGy/h. The time and temperature effects on the EPR response of this dosimeter were also studied. The results indicated that the bone sample was a suitable dosimeter especially for electron beam at high doses.
Źródło:
Nukleonika; 2009, 54, 4; 267-270
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability study of free radicals in 10 MeV electron beam irradiated quartz as an EPR dosimetry method
Autorzy:
Ziaie, F.
Mohammadzadeh, A.
Modarresi, M.
Powiązania:
https://bibliotekanauki.pl/articles/148163.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
quartz dosimeter
EPR response
dose rate
electron beam
EPR signal stability
Opis:
In this work the stability of free radicals induced by a 10 MeV electron beam in quartz samples was studied. The investigations have been done for different doses and different dose rates. For this reason, quartz samples in powder form were irradiated at different dose rates, i.e. 100, 260 and 630 kGy/min for absorbed dose range of similar to 5–80 kGy using the 10 MeV electron beam radiation. The dose values were validated using a polystyrene calorimeter system as a reference standard dosimetry system. The EPR optimum system parameters were defined and EPR responses at room temperature in air were measured and compared. The EPR signal, which is due to the free radicals induced by electron beam, was also investigated at different time intervals to check its stability. The main objective of this work was to study the feasibility of using quartz as a dosimeter. Thus, the variation of EPR signal intensities with the absorbed dose values were evaluated and plotted in a graph. The results show that the variation of dose rate, do not affect considerably the EPR response.
Źródło:
Nukleonika; 2009, 54, 4; 251-254
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł

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