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Tytuł:
The Mössbauer spectrometer MsAa-4
Autorzy:
Górnicki, R.
Ruebenbauer, K.
Powiązania:
https://bibliotekanauki.pl/articles/147400.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray spectroscopy
Mössbauer spectroscopy
spectrometers
Opis:
A description of the Mossbauer spectrometer MsAa-4 is given. The spectrometer has a modular design and it could be used as the gamma-ray spectrometer as well. It has almost entirely digital design to assure stability and repeatability. It is powered via the rechargeable battery to make it immune to the power failures. All settings are performed remotely over the Ethernet link used also to transfer data and spectrometer functions. External CAN bus could be used to attach auxiliary equipment. The status of the external equipment could be used to control spectrometer functions. Internal digital oscilloscope monitors vital functions of the spectrometer over the Ethernet link. Driving software operates under Microsoft Windows registered trademark systems and it is fully compatible with the Mosgraf-2009 data processing suite.
Źródło:
Nukleonika; 2013, 58, 1; 17-21
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A modified method for the determination of radioactive isotopes in building raw and construction materials with multichannel gamma spectrometry
Autorzy:
Charewicz, W.
Żebrowski, A.
Walkowiak, W.
Borek, B.
Powiązania:
https://bibliotekanauki.pl/articles/147083.pdf
Data publikacji:
2000
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
building materials
multichannel gamma-ray spectrometry
radioactive isotopes
Opis:
A modified method is presented for the determination of natural and artificial isotopes in building raws and materials using multichannel gamma-ray spectrometry. A procedure is given for the preparation of standards as well as for the determination of radioisotopes content in typical building raws and/or materials. Results of these determinations were compared with those from standard, tri-channel gamma spectrometry described in Instruction No. 234/95 [2] issued by the Institute of Building Technology in Warsaw, Poland.
Źródło:
Nukleonika; 2000, 45, 4; 243-247
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prompt gamma-ray methods for industrial process evaluation : a simulation study
Autorzy:
Mohammed, Mohammed Siddig H.
Alhawsawi, Abdulsalam M.
Aljohani, M. S.
Damoom, Mohammed M.
Banoqitah, Essam M.
Elmoujarkach, Ezzat
Powiązania:
https://bibliotekanauki.pl/articles/2105331.pdf
Data publikacji:
2022
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
prompt gamma ray
sealed sources
radiotracers
industrial process
Opis:
Radioisotope applications in industrial process inspection and evaluation using gamma-ray emitters provide otherwise unavailable information. Offering alternative gamma-ray sources can support the technology by complementing sources’ availability and radiation safety. This work proposes to replace gamma-ray from radioisotopes with prompt gamma-ray from the interaction of neutrons with stable isotopes injected into the industrial process or with the structural material of the industrial process equipment. Monte Carlo N-Particle Transport Code (MCNP5) was used to simulate the irradiation of two-phase fl ow pipes by 252Cf neutron source. Two simulations were run for each pipe, with and without mixing the liquid phase with the stable isotope 157Gd. The detected gamma-ray spectra were analysed, and images of the two phases inside the pipes were produced. The images were compared to images obtained from simulations of gamma transmission measurement using 60Co. Furthermore, results for prompt gamma computed tomography (CT) were presented and discussed. The studies’ outcomes indicate the potential of prompt gamma-ray to carry out the sealed sources applications of gamma transmission measurements and imaging.
Źródło:
Nukleonika; 2022, 67, 1; 11--18
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Self-absorption correction in gamma-ray spectrometry of environmental samples - an overview of methods and correction values obtained for the selected geometries
Autorzy:
Jodłowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/148531.pdf
Data publikacji:
2006
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray spectrometry
self-attenuation
self-absorption
correction factor
Opis:
Of major concern are the self-absorption correction factors Cs in precise gamma-ray spectrometry of environmental samples. The overview of Cs determination methods (experimental, Monte Carlo calculations, analytical function application) is presented. Among several available methods, the author chose the one proposed by Debertin where the uncertainty level of Cs correction factor is 1÷2%. The point-like detector model is assumed whilst its efficiency is taken to be proportional to the weighted sum (integral) of the number of photons coming from sample volume elements. Computer program was developed to support the computation of Cs by the Debertin's method for samples in cylindrical geometries and Marinelli beakers. The input data are sample dimensions, density and the mass attenuation coefficient. The Cs uncertainty due to an arbitrarily chosen position of a point-like detector would not exceed 1% for the considered photon energies and the sample density range. Utilising this computer program, the relationships Cs(E,ń) were obtained for the applied geometries and a SiO2 matrix to support routine measurements. The SiO2 matrix is widely encountered in environmental spectrometry. This relationship was derived by fitting the computed data with the function Cs(E,ń) in the form proposed by Bolivar. It was shown that while handling this function to samples with the H2O matrix, the error involved in estimations would not exceed 3%.
Źródło:
Nukleonika; 2006, 51,suppl.2; 21-25
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gamma-Ray Spectrometry Laboratory for high-precision measurements of radionuclide concentrations in environmental samples
Autorzy:
Jodłowski, P.
Kalita, S. J.
Powiązania:
https://bibliotekanauki.pl/articles/148485.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray spectrometry
environmental samples
efficiency
self-absorption
coincidence summing
Opis:
The paper outlines the methodology used in the Gamma-Ray Spectrometry Laboratory for high-precision measurements of radionuclide activity concentrations in environmental samples. The Laboratory equipment includes a semiconductor detector HPGe with a 42% relative efficiency. The detector is placed in a Pb housing made of bricks 10 cm in thickness. Three measurement geometries are considered: Marinelli beakers 710 cm3 in volume and two cylindrical geometries 121 and 48 cm3 in volume. In the efficiency calibration (E = 32 division sign 1836 keV) mixed gamma standard solutions were used. Obtained experimental efficiency values epsilon were fitted with two quadratic functions. The junction point is that equivalent to 200 keV. Uncertainty of the calibration curve is 2% for E > 200 keV. The relationship between the total efficiency and the energy epsilon t(E) was also found for energies E = 33 division sign 1250 keV. Self-absorption correction factors Cs are calculated by the method proposed by K. Debertin, the uncertainty level being 1 division sign 2% for E > 100 keV. These correction factors are calculated by an original computer program. Coincidence summing correction factors Cc for the selected nuclides are derived using the ETNA computer program, basing on the relationships epsilon(E) and epsilon t(E). Minimum detectable activity (MDA) for selected nuclides encountered in environmental samples was determined for the water matrix. The methodology used was successfully verified in the course of international intercomparison measurements.
Źródło:
Nukleonika; 2010, 55, 2; 143-148
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:
Measurement of anthropogenic radionuclides in post-Fukushima Pacific seawater samples
Autorzy:
Lutter, G.
Tzika, F.
Hult, M.
Aoyama, M.
Hamajima, Y.
Marissens, G.
Stroh, H.
Powiązania:
https://bibliotekanauki.pl/articles/148313.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
detection limit
Fukushima
gamma-ray spectrometry
Monte Carlo
radiocesium
underground laboratory
Opis:
Following the accident at the Daiichi Fukushima nuclear power plant in 2011, a vast number of Pacific seawater samples from many locations far from Fukushima have been collected by Japanese investigators. Due to dilution, the activities of radionuclides from North Pacifi c seawater samples are very low, which calls for extraordinary measures when being measured. This study focuses on the metrological aspects of the gamma-ray spectrometry measurements performed on such samples in two underground laboratories; at HADES (by JRC- -IRMM in Belgium), and at Ogoya (by Kanazawa University in Japan). Due to many samples and long measurement times, all available HPGe detectors needed to be employed. In addition to single coaxial detectors, this involved multidetector systems and well detectors. Optimization of detection limits for different radionuclides and detectors was performed using Monte Carlo simulations.
Źródło:
Nukleonika; 2015, 60, No. 3, part 2; 545-550
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Large Sample Neutron Activation Analysis: correction for neutron and gamma attenuation
Autorzy:
Tzika, F.
Stamatelatos, I.
Kalef-Ezra, J.
Bode, P.
Powiązania:
https://bibliotekanauki.pl/articles/147265.pdf
Data publikacji:
2004
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
neutron activation analysis
neutron self-shielding
gamma-ray attenuation
MCNP code
Opis:
A Large Sample Neutron Activation Analysis (LSNAA) facility is under development at the GRR-1 research reactor, NCSR "Demokritos". The LSNAA facility design incorporates sample irradiation in the reactor graphite thermal neutron column and subsequent measurement of the activity induced in a gamma spectroscopy system with gamma ray transmission measurement options included. The Monte Carlo neutron and photon transport code MCNP-4C was used to model the facility. Appropriate correction factors accounting for neutron field perturbation during sample irradiation and high-purity germanium detector efficiency for the volume source were derived. The results of the computations were experimentally verified by measurements for a set of known materials. The LSNAA facility will be used to perform multi-element, non-destructive, contamination-free analysis of large volume samples with high sensitivity and excellent sampling. End-users of the facility will be archaeological, environmental, bio-medical research laboratories and industry.
Źródło:
Nukleonika; 2004, 49, 3; 115-121
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Utilization of an energy-resolving detection system for mammography applications : a preliminary study
Autorzy:
Taha, Eslam M.
Elmoujarkach, Ezzat A.
Balamesh, Ahmed
Alzaidi, Samir A.
Alhawsawi, Abdulsalam M.
Powiązania:
https://bibliotekanauki.pl/articles/2171786.pdf
Data publikacji:
2022
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
energy-resolving detection systems
gamma-ray imaging
GATE simulation toolkit
mammography
Opis:
Breast cancer remains one of the major causes of mortality among female cancer patients. This fact caused a spark in the medical field, which in turn helped to improve the diagnostic and treatment of breast cancer patients over the years making this field always active with new ideas and innovative methods. In our study, a new method was explored using an energy-resolving detection system made from a NaI (Tl) scintillation detector to detect the gamma photons from an Am-241 radiation source to try and construct an image by scanning the American College of Radiology (ACR) mammography phantom. In addition to the experimental work, a Geant4 Application for Tomographic Emission (GATE) toolkit was used to investigate more complex options to improve the image quality of mammographic systems, which is limited by the experimental setup. From the experimental setup, the researchers were able to construct an image using the 26.3 keV and the 59.5 keV energy photons, to show the largest size tumour (12 mm) in the ACR phantom. With an improved setup in the simulation environment, the majority of the ACR phantom tumours was visible using both energy windows from the 26.3 keV and the 59.5 keV, where the 26.3 keV yielded better quality images showing four tumours compared to three when using 59.5 keV. The simulation results were promising; however, several improvements need to be incorporated into the experimental work so that the system can generate high-resolution mammographic images similar to the ones obtained by the GATE simulation setup.
Źródło:
Nukleonika; 2022, 67, 2; 35--40
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fluka simulation of PGNAA system for determining heavy metal pollution in the soil sample
Autorzy:
Zhang, Can
Yang, Jianbo
Li, Rui
Qiao, Yujie
Zhang, Xu
Xu, Jie
Powiązania:
https://bibliotekanauki.pl/articles/146960.pdf
Data publikacji:
2020
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
PGNAA
Fluka
heavy metal
prompt gamma-ray yield
metal ciężki
szybka wydajność
promieniowanie gamma
Opis:
This study presented a self-designed prompt gamma neutron activation analysis (PGNAA) model and used Fluka simulation to simulate the heavy metals (Mn, Cu, Hg, Ni, Cr, Pb) in soil samples. The relationship between the prompt gamma-ray yield of each heavy metal and soil thickness, content of heavy metals in the soil, and source distance was obtained. Simulation results show that the prompt gamma-ray yield of each heavy metal increases with the increase in soil thickness and reaches saturation at 18 cm. The greater the proportion of heavy metals in the soil, the greater the prompt gamma-ray yield. The highest content is approximately 3%, and the change in distance between the neutron source and soil sample does not affect the prompt gamma-ray yield of heavy metals.
Źródło:
Nukleonika; 2020, 65, 1; 13-17
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Np-237 incineration study in various beams in ADS setup QUINTA
Autorzy:
Kilim, S.
Strugalska-Gola, E.
Szuta, M.
Bielewicz, M.
Tyutyunnikov, S. I.
Furman, W. I.
Adam, J.
Stegailov, V. I.
Powiązania:
https://bibliotekanauki.pl/articles/146295.pdf
Data publikacji:
2018
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
Np-237
accelerator-driven system
ADS
gamma-ray spectrometry
fission
neutron capture
Opis:
Neptunium-237 samples were irradiated in a spallation neutron fi eld produced in accelerator-driven system (ADS) setup QUINTA. Five experiments were carried out on the accelerators at the JINR in Dubna – one in carbon (C6+), three in deuteron, and one in a proton beam. The energy in carbon was 24 GeV, in deuteron 2, 4 and 8 GeV, respectively, and 660 MeV in the proton beam. The incineration study method was based on gamma-ray spectrometry. During the analysis of the spectra several fi ssion products and one actinide were identifi ed. Fission product activities yielded the number of fi ssions. The actinide (Np-238), a result of neutron capture by Np-237, yielded the number of captures. The main goal of this work was to fi nd out if and how the incineration rate depended on parameters of the accelerator beam.
Źródło:
Nukleonika; 2018, 63, 1; 17-22
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Time of soil water thermodynamic equilibrium during retention curve establishment using gamma-ray beam attenuation
Autorzy:
Pires, L.
Bacchi, O.
Reichardt, K.
Powiązania:
https://bibliotekanauki.pl/articles/148674.pdf
Data publikacji:
2005
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray attenuation
time of equilibrium
pressure chamber
soil water retention curve
Opis:
The soil water retention curve (SWRC) represents a fundamental part of the characterization of the soil hydraulic properties. The establishment of SWRC is usually time-consuming and presents several problems such as the difficulty of a correct judgment of the time of equilibrium. This work presents a new methodology that involves gammaray beam attenuation technique associated with the traditional pressure chambers, having as objective the more precise judgment of the time to attain equilibrium. The gamma-ray source used has an activity of 3.7 GBq consisting of 241Am, with peak energy of 59.54 keV. For the determination of retention curves using the gamma-ray attenuation technique, an acrylic pressure chamber was projected and constructed to be positioned between the source and detector with the gamma-ray beam crossing the center of the chamber and the soil sample during water extraction. The proposed technique allowed, through a specifically elaborated software for data acquisition, to evaluate with precision the exact instant of the equilibrium and, consequently, to obtain the right moment to change the chamber pressure to a new desired level, leading to a reduction of the time required for the whole retention curve determination. The results obtained show that the gamma-ray attenuation technique can be very useful as an auxiliary tool to evaluate SWRC, utilizing the Richards chamber.
Źródło:
Nukleonika; 2005, 50, 4; 173-177
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gamma-ray beam attenuation to assess the influence of soil texture on structure deformation
Autorzy:
Pires, L.
Bacchi, O.
Dias, N.
Powiązania:
https://bibliotekanauki.pl/articles/147480.pdf
Data publikacji:
2006
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray attenuation
soil physical properties
soil structure deformation
soil sampling
soil porosity
Opis:
Gamma-ray beam attenuation is a non-invasive technique that permits analysis of soil porosity without disturbing the region of interest of the core sample. The technique has as additional advantage to allow measurements point by point on a millimetric scale in contrast to other methodologies that are invasive and analyze the soil properties in the bulk sample volume. Soil porosity can be used as an important parameter to quantify soil structural damages, which affect soil aeration, water movement and retention. In this study, porosities of three soils different in texture were measured at various positions in order to analyze the impact of the sampling procedure on the structure of each particular soil texture. The gamma-ray attenuation system consisted of an 241Am radioactive source having an activity of 3.7 GBq, collimated with cylindrical lead collimators of 2 mm diameter. The results obtained show the presence of dense regions near the edges of samples and that different soil textures can suffer distinct deformations at sampling.
Źródło:
Nukleonika; 2006, 51, 2; 125-129
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design, construction and performance of a pressure chamber for water retention curve determination through traditional and nuclear methods
Autorzy:
Pires, L.
Bacchi, O.
Powiązania:
https://bibliotekanauki.pl/articles/146181.pdf
Data publikacji:
2006
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
soil water potential
gamma-ray attenuation
soil water content
soil physics
radioisotope application
Opis:
We present in this work a detailed design of a small low-pressure chamber outfitted with a ceramic porous plate for evaluating the soil water retention curve (SWRC) in the water potential range from 0 to -100 kPa. The chamber is made of acrylic and permits the use of one unique soil sample each time. The use of this chamber allows quick measurements of soil moisture using nuclear (based on gamma-ray attenuation) and conventional methods and SWRC determinations made with the designed chamber are in agreement with those obtained using a commercial low-pressure chamber. The chamber was designed especially for testing the use of the nuclear method as an auxiliary tool for SWRC determinations but it can be easily adapted for routine investigations and a practical alternative for the conventional SWRC method.
Źródło:
Nukleonika; 2006, 51, 4; 225-230
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gamma-ray computed tomography as a tool to evaluate porosity changes along depth for surface crusted soils
Autorzy:
Pires, L. F.
Bacchi, O. O. S.
Reichardt, K.
Dias, N. M. P.
Powiązania:
https://bibliotekanauki.pl/articles/146838.pdf
Data publikacji:
2007
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray attenuation
soil density
soil structure
soil surface sealing
241 Am
applied nuclear physics
gamma tomography
Opis:
Assessment of changes in porosity (ö) along depth for soils with surface crusting is difficult because conventional soil physical investigation tools are destructive and usually require a long period of time for preparation and analysis of the samples. Computed tomography (CT) has frequently been used as a method to evaluate soil structure in a nondestructive, sensitive, and rapid manner. CT data can be used for measuring at a millimetric scale changes in ö along depth for soils with surface crusting. The main objective of this work was to investigate the sensibility of the gamma-ray CT to assess soil structural changes along depth in samples presenting structural crust. CT images were taken with a first generation scanner of 1.14 mm resolution along eight different soil layers within the 0 28 mm depth. Porosity increased along depth up to the 14 17.5 mm layer. Through the analysis of the ö distribution of each layer it was possible to show that the sealed surface layer presented ö values of approximately 30%, while the other layers were greater than 30% up to 60% (macropore regions). The sealing crust thickness was estimated to be in the range of 2.3 3.5 mm.
Źródło:
Nukleonika; 2007, 52, 3; 125-131
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
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