scholarly journals Validation of EFFTRAN for efficiency transfer to distant geometries and volume sources

2021 ◽  
Author(s):  
H. Ramebäck ◽  
S. Jonsson ◽  
T. Vidmar
Keyword(s):  
Methyl Methacrylate ◽  
Gamma Ray ◽  
Germanium Detector ◽  
Gamma Ray Spectrometry ◽  
Volume Source ◽  
Two Stage ◽  
Poly Methyl Methacrylate ◽  
Fit For Purpose

AbstractThe efficiency transfer procedure from a geometry where a volume source was placed directly on the endcap of a germanium detector to three different distant geometries was carried out using the EFFTRAN code. One of these distant geometries included absorbers consisting of poly(methyl methacrylate). The efficiency transfer to this geometry therefore had to be realized as a two-stage transfer, since a direct efficiency transfer is not possible using EFFTRAN in such a case. Efficiency transfer to all three distant geometries yielded results which can be considered as fit-for-purpose in e.g. most of the applications of gamma ray spectrometry.

scholarly journals Determination of the activity concentration levels of the artificial radionuclide137Cs in soil samples collected from Qatar using high-resolution gamma-ray spectrometry

2016 ◽  
Vol 44 ◽  
pp. 1660237
Author(s):  
Huda Al-Sulaiti ◽  
Tabassum Nasir ◽  
K. S. Al Mugren ◽  
N. Alkhomashi ◽  
N. Al-Dahan ◽  
...  
Keyword(s):  
High Resolution ◽  
Nuclear Power ◽  
Activity Concentration ◽  
Gamma Ray ◽  
Germanium Detector ◽  
Soil Samples ◽  
Gamma Ray Spectrometry ◽  
Activity Concentrations ◽  
High Resolution Gamma

The goal of this study was to establish the first baseline measurements for radioactivity concentration of the artificial radionuclide [Formula: see text]Cs in soil samples collected from the Qatarian peninsula. The work focused on the determination of the activity concentrations levels of man-made radiation in 129 soil samples collected across the landscape of the State of Qatar. All the samples were collected before the most recent accident in Japan, “the 2011 Fukushima Dai-ichi nuclear power plant accident”. The activity concentrations have been measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector situated in a low-background environment with a copper inner-plated passive lead shield. A radiological map showing the activity concentrations of [Formula: see text]Cs is presented in this work. The concentration was[Formula: see text]found to range from 0.21 to 15.41 Bq/kg. The highest activity concentration of [Formula: see text]Cs was observed in sample no. 26 in North of Qatar. The mean value was found to be around 2.15 ± 0.27 Bq/kg. These values lie within the expected range relative to the countries in the region. It is expected that this contamination is mainly due to the Chernobyl accident on 26 April 1986, but this conclusion cannot be confirmed because of the lack of data before this accident.

scholarly journals ESTIMATION OF THE EFFICIENCY OF THE DRY METHOD OF DECONTAMINATION OF SURFACE CONTAMINATION OF ALPHA-EMITTING-RADIONUCLIDES

2019 ◽  
Vol 98 (8) ◽  
pp. 878-884
Author(s):  
Igor P. Korenkov ◽  
T. N. Lashchenova ◽  
N. K. Shandala ◽  
A. I. Ermakov ◽  
A. B. Mayzik
Keyword(s):  
Cluster Analysis ◽  
Gamma Ray ◽  
Specific Activity ◽  
Germanium Detector ◽  
Decontamination Factor ◽  
Surface Contamination ◽  
Gamma Ray Spectrometry ◽  
Building Structures ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent

The article describes the evaluation of the efficiency of using the technology of dry method of decontamination of α-radionuclides from working surfaces of premises for different materials, equipment and building structures. Materials and methods. Instruments for measuring of ambient dose equivalent rate (ADER) with a lower limit of 0.03 μSv/h. Specific activity of α-radionuclides in the samples was determined by radiometric, radiochemical and spectrometric methods using standard methods in the accredited laboratory. The measurements in situ were also carried out using the ISOCS «CANBERRA» mobile gamma-ray spectrometry system with high purity germanium detector and a collimator. Technological equipment included industrial vacuum cleaner with nozzles; high-pressure device; packing sets for RAW collection; HEPA filters; personal protective equipment. Results. Maps of spatial distribution of surface α-contamination in the building was constructed. We performed cluster analysis of data for zoning of contaminated surfaces. The decontamination factor for porous (brick, concrete), smooth (wood, brown tiles, laminate) and sticky (bitumen, mastic) surfaces was determined. Conclusion. The cluster analysis made it possible to identify 4 levels of surface α- and β- contamination, particles/cm2 ∙ min: zone I - for α- above 50, for β- above 10,000; zone II - for α- 5-50, for β- 2,000-10,000; zone III - for α- no more than 5, for β- 2000; zone IV - corresponds to the background values of the workspace surfaces. The dry decontamination method revealed a high content of fine dust aerosol fraction deposited in the lungs. To increase the efficiency of dust suppression, water aerosol with droplet size of 100 - 400 microns and quartz sand with particle size of 100-200 microns were sprayed at the rate of 200-400 g per 1 m2. The decontamination coefficient depends on the coating material and the level of surface contamination: concrete - 91 to 97.8%; brick - 85-86%, wood - 38.8-53%; brownstone tiles - up to 29%; mastic - 22-28%; bitumen - 15.9-20%. To protect the personnel, radiation-hygienic rationing of PM10 and PM2,5 content is necessary.

Cytotoxicity of Eluates from a Gamma-Ray-Polymerized Poly(Methyl Methacrylate)

2004 ◽  
Vol 18 (3) ◽  
pp. 223-231 ◽  
Author(s):  
Murat Cav[UNKNOWN]it Cehrel[UNKNOWN] ◽  
Sa[UNKNOWN]me Sah[UNKNOWN]in ◽  
Koray Ergunay ◽  
Semsett[UNKNOWN]n Ustaceleb ◽  
Ugur Adnan Sev[UNKNOWN]l
Keyword(s):  
Methyl Methacrylate ◽  
Gamma Ray ◽  
Poly Methyl Methacrylate

scholarly journals Effect of .GAMMA.-Ray Irradiation on Polystyrene, Poly(methyl methacrylate), and Their Copolymer Prepared by Cast Polymerization.

1998 ◽  
Vol 55 (8) ◽  
pp. 433-439
Author(s):  
Takahiro TSUKAME ◽  
Michio KUTSUZAWA ◽  
Hideki SAITOH ◽  
Yoshio SHIBASAKI
Keyword(s):  
Methyl Methacrylate ◽  
Gamma Ray ◽  
Poly Methyl Methacrylate ◽  
Gamma Ray Irradiation

7 years of monitoring of 40K in surface water samples from Olt River, Romania

2020 ◽  
pp. 49-60
Author(s):  
Mihaela Roxana Ene ◽  
◽  
Gheorghe Bulubasa ◽  
Alina Florentina Miu ◽  
◽  
...  
Keyword(s):  
Surface Water ◽  
Water Samples ◽  
Gamma Ray ◽  
Germanium Detector ◽  
Gamma Ray Spectrometry ◽  
Sampling Point ◽  
Naturally Occurring ◽  
Significant Difference ◽  
Monitoring Study ◽  
Surface Water Samples

The aim of this study was to determine naturally occurring radionuclide 40K in surface water samples from Olt River, Romania. A monitoring study during 7 years (2012-2018) was accomplished. A number of 728 surface water samples were collected and analysed. Several hundred pollution sources were identified for the Olt River basin in Romania. This study is of particular importance since it is the first effort to evaluate the activity concentrations of 40K in surface water from Romania for such a long period. For this reason, two sampling points along the Olt River were chosen, the first one upstream of the discharge point of the magistrate channel "Deversor Olt" (reference location) and respectively the second sampling point downstream of the liquid effluents discharges point (indicator location). The radioactivity concentration of 40K was determined from the 1460.8 keV photopeak. The method used was high resolution gamma ray spectrometry performed with a hyperpure germanium detector. An activity concentration for 40K, no more than 2.14 ± 0.32 Bq l -1 , is observed, but the values recorded for the background location had a slight, but not significant difference compared with the values recorded in the second sampling point.

scholarly journals Natural radiation exposure and radon exhalation rate of building materials used in Turkey

2018 ◽  
Vol 33 (2) ◽  
pp. 159-166
Author(s):  
Seref Turhan ◽  
Alper Temirci ◽  
Asli Kurnaz ◽  
Aydan Altikulac ◽  
Elif Goren ◽  
...  
Keyword(s):  
Radiation Exposure ◽  
Building Materials ◽  
Gamma Ray ◽  
Germanium Detector ◽  
Gamma Ray Spectrometry ◽  
Limit Values ◽  
Radon Exhalation ◽  
Activity Concentrations ◽  
Materials Used ◽  
Radioactivity Levels

Measuring the natural radioactivity levels and radon exhalation rates (surface and mass) in building materials is essential to evaluate the extent of radiation exposure (external and internal) for residents in dwellings. Gamma-ray spectrometry with a high purity germanium detector was used to measure the activity concentrations of 226Ra, 232Th, and 40K in some building materials used in Turkey. Moreover, an active radon gas analyser with an accumulation container was used to measure their radon surface and mass exhalation rates. Results showed that the activity concentrations of 226Ra, 232Th, and 40K varied from 5.2 ? 0.6 (satin plaster) to 187.0 ? 2.4 (granite) Bqkg-1, 2.6 ? 0.8 (gypsum) to 172.2 ? 7.6 (granite) Bqkg-1 and 12.3 ? ? 17.0 (sand) to 1958.0 ? 83.4 (brick) Bqkg-1, respectively. Radon surface and mass exhalation rates varied from 2.9 (marble) to 2734.6 mBqm-2h-1(granite) and 0.033 (marble) to 53.866 mBqkg-1h-1 (granite), respectively. The activity concentration index, indoor absorbed gamma dose rate and corresponding annual effective dose were estimated and compared with the recommended limit values. The results indicated that the building materials sampled presented no significant radiological risk.

Synthesis of cationic poly(methyl methacrylate)-poly(N-isopropyl acrylamide) core-shell latexes via two-stage emulsion copolymerization

Polymer ◽  
2005 ◽  
Vol 46 (4) ◽  
pp. 1181-1188 ◽  
Author(s):  
Andrea M. Santos ◽  
Abdelhamid Elaïssari ◽  
José M.G. Martinho ◽  
Christian Pichot
Keyword(s):  
Methyl Methacrylate ◽  
Core Shell ◽  
Two Stage ◽  
Emulsion Copolymerization ◽  
Poly Methyl Methacrylate ◽  
Isopropyl Acrylamide
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