Base de dados : MEDLINE
Pesquisa : E05.799.700 [Categoria DeCS]
Referências encontradas : 3640 [refinar]
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[PMID]:29176834
[Au] Autor:Wieczorek A; Dulski K; Niedzwiecki S; Alfs D; Bialas P; Curceanu C; Czerwinski E; Danel A; Gajos A; Glowacz B; Gorgol M; Hiesmayr B; Jasinska B; Kacprzak K; Kaminska D; Kaplon L; Kochanowski A; Korcyl G; Kowalski P; Kozik T; Krzemien W; Kubicz E; Kucharek M; Mohammed M; Pawlik-Niedzwiecka M; Palka M; Raczynski L; Rudy Z; Rundel O; Sharma NG; Silarski M; Uchacz T; Wislicki W; Zgardzinska B; Zielinski M; Moskal P
[Ad] Endereço:Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, Kraków, Poland.
[Ti] Título:Novel scintillating material 2-(4-styrylphenyl)benzoxazole for the fully digital and MRI compatible J-PET tomograph based on plastic scintillators.
[So] Source:PLoS One;12(11):e0186728, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A novel plastic scintillator is developed for the application in the digital positron emission tomography (PET). The novelty of the concept lies in application of the 2-(4-styrylphenyl)benzoxazole as a wavelength shifter. The substance has not been used as scintillator dopant before. A dopant shifts the scintillation spectrum towards longer wavelengths making it more suitable for applications in scintillators of long strips geometry and light detection with digital silicon photomultipliers. These features open perspectives for the construction of the cost-effective and MRI-compatible PET scanner with the large field of view. In this article we present the synthesis method and characterize performance of the elaborated scintillator by determining its light emission spectrum, light emission efficiency, rising and decay time of the scintillation pulses and resulting timing resolution when applied in the positron emission tomography. The optimal concentration of the novel wavelength shifter was established by maximizing the light output and it was found to be 0.05 ‰ for cuboidal scintillator with dimensions of 14 mm x 14 mm x 20 mm.
[Mh] Termos MeSH primário: Benzoxazóis/química
Imagem por Ressonância Magnética
Tomografia por Emissão de Pósitrons
Contagem de Cintilação/instrumentação
Estirenos/química
Tomografia
[Mh] Termos MeSH secundário: Luz
Peso Molecular
Polimerização
Espectrometria de Fluorescência
Temperatura Ambiente
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Benzoxazoles); 0 (Styrenes)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171219
[Lr] Data última revisão:
171219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186728


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[PMID]:28452339
[Au] Autor:Stockhoff M; Jan S; Dubois A; Cherry SR; Roncali E
[Ad] Endereço:Department of Biomedical Engineering, University of California Davis, One Shields Avenue, Davis, CA 95616, United States of America.
[Ti] Título:Advanced optical simulation of scintillation detectors in GATE V8.0: first implementation of a reflectance model based on measured data.
[So] Source:Phys Med Biol;62(12):L1-L8, 2017 Jun 21.
[Is] ISSN:1361-6560
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Typical PET detectors are composed of a scintillator coupled to a photodetector that detects scintillation photons produced when high energy gamma photons interact with the crystal. A critical performance factor is the collection efficiency of these scintillation photons, which can be optimized through simulation. Accurate modelling of photon interactions with crystal surfaces is essential in optical simulations, but the existing UNIFIED model in GATE is often inaccurate, especially for rough surfaces. Previously a new approach for modelling surface reflections based on measured surfaces was validated using custom Monte Carlo code. In this work, the LUT Davis model is implemented and validated in GATE and GEANT4, and is made accessible for all users in the nuclear imaging research community. Look-up-tables (LUTs) from various crystal surfaces are calculated based on measured surfaces obtained by atomic force microscopy. The LUTs include photon reflection probabilities and directions depending on incidence angle. We provide LUTs for rough and polished surfaces with different reflectors and coupling media. Validation parameters include light output measured at different depths of interaction in the crystal and photon track lengths, as both parameters are strongly dependent on reflector characteristics and distinguish between models. Results from the GATE/GEANT4 beta version are compared to those from our custom code and experimental data, as well as the UNIFIED model. GATE simulations with the LUT Davis model show average variations in light output of <2% from the custom code and excellent agreement for track lengths with R > 0.99. Experimental data agree within 9% for relative light output. The new model also simplifies surface definition, as no complex input parameters are needed. The LUT Davis model makes optical simulations for nuclear imaging detectors much more precise, especially for studies with rough crystal surfaces. It will be available in GATE V8.0.
[Mh] Termos MeSH primário: Método de Monte Carlo
Fenômenos Ópticos
Fótons
Contagem de Cintilação
[Mh] Termos MeSH secundário: Tomografia por Emissão de Pósitrons
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171218
[Lr] Data última revisão:
171218
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1088/1361-6560/aa7007


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[PMID]:28452337
[Au] Autor:Raczynski L; Wislicki W; Krzemien W; Kowalski P; Alfs D; Bednarski T; Bialas P; Curceanu C; Czerwinski E; Dulski K; Gajos A; Glowacz B; Gorgol M; Hiesmayr B; Jasinska B; Kaminska D; Korcyl G; Kozik T; Krawczyk N; Kubicz E; Mohammed M; Pawlik-Niedzwiecka M; Niedzwiecki S; Palka M; Rudy Z; Rundel O; Sharma NG; Silarski M; Smyrski J; Strzelecki A; Wieczorek A; Zgardzinska B; Zielinski M; Moskal P
[Ad] Endereço:Department of Complex Systems, National Centre for Nuclear Research, 05-400 Otwock-Swierk, Poland.
[Ti] Título:Calculation of the time resolution of the J-PET tomograph using kernel density estimation.
[So] Source:Phys Med Biol;62(12):5076-5097, 2017 Jun 21.
[Is] ISSN:1361-6560
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In this paper we estimate the time resolution of the J-PET scanner built from plastic scintillators. We incorporate the method of signal processing using the Tikhonov regularization framework and the kernel density estimation method. We obtain simple, closed-form analytical formulae for time resolution. The proposed method is validated using signals registered by means of the single detection unit of the J-PET tomograph built from a 30 cm long plastic scintillator strip. It is shown that the experimental and theoretical results obtained for the J-PET scanner equipped with vacuum tube photomultipliers are consistent.
[Mh] Termos MeSH primário: Tomografia por Emissão de Pósitrons/instrumentação
Contagem de Cintilação/instrumentação
[Mh] Termos MeSH secundário: Desenho de Equipamento
Seres Humanos
Plásticos
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Plastics)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171218
[Lr] Data última revisão:
171218
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1088/1361-6560/aa7005


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[PMID]:28915436
[Au] Autor:Al-Shboul KF; Alali AE; Batayneh IM; Al-Khodire HY
[Ad] Endereço:Department of Nuclear Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan. Electronic address: kfshboul@just.edu.jo.
[Ti] Título:Radiation hazards and lifetime risk assessment of tap water using liquid scintillation counting and high-resolution gamma spectrometry.
[So] Source:J Environ Radioact;178-179:245-252, 2017 Nov.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In this work, two complementary techniques, viz. liquid scintillation counting and high-resolution gamma spectrometry are utilized to analyze radionuclides concentrations in tap water of Irbid governorate, Jordan, and study their correlation. Gross alpha and gross beta concentrations, in the tap water samples collected from the nine districts of Irbid governorate, ranged from <82 to 484 mBq/L with a mean of 295 mBq/L and from <216 to 984 mBq/L with a mean of 611 mBq/L, respectively. Furthermore, gamma spectrometry analysis, for the tap water samples, shows that the activity concentrations of Ra, Th, and K ranged between <19 and 302 mBq/L, 24 to 119 mBq/L, and <101 to 342 mBq/L, respectively. There was a weak or even no correlation among the identified natural radionuclides with no trace of artificial radioactivity. In addition, the results of both techniques show that storing tap water in drilled wells leads to higher levels of radioactivity concentrations beyond the international permissible limits. Furthermore, the average lifetime risk and annual effective dose received by age-grouped inhabitants due to direct and indirect tap water consumption are evaluated, where most of the received dose is attributed to Ra.
[Mh] Termos MeSH primário: Água Potável/química
Exposição à Radiação/estatística & dados numéricos
Monitoramento de Radiação
Poluição Radioativa da Água/estatística & dados numéricos
[Mh] Termos MeSH secundário: Seres Humanos
Jordânia
Dose de Radiação
Medição de Risco
Contagem de Cintilação
Espectrometria gama
Poluentes Radioativos da Água/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Drinking Water); 0 (Water Pollutants, Radioactive)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171110
[Lr] Data última revisão:
171110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170916
[St] Status:MEDLINE


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[PMID]:28796751
[Au] Autor:Asano Y
[Ad] Endereço:*Spring-8 Center/RIKEN, 1-1 Koto, Sayo, Hyogo 679-5148, Japan.
[Ti] Título:Estimation of Airborne Radioactivity Induced by 8-GeV-Class Electron LINAC Accelerator.
[So] Source:Health Phys;113(4):237-245, 2017 Oct.
[Is] ISSN:1538-5159
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Airborne radioactivity induced by high-energy electrons from 6 to 10 GeV is estimated by using analytical methods and the Monte Carlo codes PHITS and FLUKA. Measurements using a gas monitor with a NaI(Tl) scintillator are carried out in air from a dump room at SACLA, an x-ray free-electron laser facility with 7.8-GeV electrons and are compared to the simulations.
[Mh] Termos MeSH primário: Poluentes Radioativos do Ar
Síncrotrons
[Mh] Termos MeSH secundário: Monitoramento Ambiental/métodos
Exposição por Inalação
Método de Monte Carlo
Radioatividade
Contagem de Cintilação/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants, Radioactive)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE
[do] DOI:10.1097/HP.0000000000000700


  6 / 3640 MEDLINE  
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[PMID]:28327464
[Au] Autor:Derenzo SE
[Ad] Endereço:Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States of America.
[Ti] Título:Monte Carlo simulations of time-of-flight PET with double-ended readout: calibration, coincidence resolving times and statistical lower bounds.
[So] Source:Phys Med Biol;62(9):3828-3858, 2017 May 07.
[Is] ISSN:1361-6560
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This paper demonstrates through Monte Carlo simulations that a practical positron emission tomograph with (1) deep scintillators for efficient detection, (2) double-ended readout for depth-of-interaction information, (3) fixed-level analog triggering, and (4) accurate calibration and timing data corrections can achieve a coincidence resolving time (CRT) that is not far above the statistical lower bound. One Monte Carlo algorithm simulates a calibration procedure that uses data from a positron point source. Annihilation events with an interaction near the entrance surface of one scintillator are selected, and data from the two photodetectors on the other scintillator provide depth-dependent timing corrections. Another Monte Carlo algorithm simulates normal operation using these corrections and determines the CRT. A third Monte Carlo algorithm determines the CRT statistical lower bound by generating a series of random interaction depths, and for each interaction a set of random photoelectron times for each of the two photodetectors. The most likely interaction times are determined by shifting the depth-dependent probability density function to maximize the joint likelihood for all the photoelectron times in each set. Example calculations are tabulated for different numbers of photoelectrons and photodetector time jitters for three 3 × 3 × 30 mm scintillators: Lu SiO :Ce,Ca (LSO), LaBr :Ce, and a hypothetical ultra-fast scintillator. To isolate the factors that depend on the scintillator length and the ability to estimate the DOI, CRT values are tabulated for perfect scintillator-photodetectors. For LSO with 4000 photoelectrons and single photoelectron time jitter of the photodetector J = 0.2 ns (FWHM), the CRT value using the statistically weighted average of corrected trigger times is 0.098 ns FWHM and the statistical lower bound is 0.091 ns FWHM. For LaBr :Ce with 8000 photoelectrons and J = 0.2 ns FWHM, the CRT values are 0.070 and 0.063 ns FWHM, respectively. For the ultra-fast scintillator with 1 ns decay time, 4000 photoelectrons, and J = 0.2 ns FWHM, the CRT values are 0.021 and 0.017 ns FWHM, respectively. The examples also show that calibration and correction for depth-dependent variations in pulse height and in annihilation and optical photon transit times are necessary to achieve these CRT values.
[Mh] Termos MeSH primário: Tomografia por Emissão de Pósitrons/métodos
Dosímetros de Radiação/normas
Contagem de Cintilação/instrumentação
[Mh] Termos MeSH secundário: Calibragem
Elétrons
Funções Verossimilhança
Lutécio/efeitos da radiação
Método de Monte Carlo
Fótons
Distribuição Aleatória
Contagem de Cintilação/métodos
Contagem de Cintilação/normas
Compostos de Silício/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Silicon Compounds); 0 (dilutetium silicon pentaoxide); 5H0DOZ21UJ (Lutetium)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE
[do] DOI:10.1088/1361-6560/aa6862


  7 / 3640 MEDLINE  
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[PMID]:28213127
[Au] Autor:May D; Nelson AN; Schultz MK
[Ad] Endereço:State Hygienic Laboratory at the University of Iowa, Coralville, IA 52241, United States; Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States. Electronic address: dustin-may@uiowa.edu.
[Ti] Título:Quantitation of lead-210 ( Pb) using lead-203 ( Pb) as a "Massless" yield tracer.
[So] Source:J Environ Radioact;171:93-98, 2017 May.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Determination of Pb-210 ( Pb) in aqueous solution is a common radioanalytical challenge in environmental science. Widely used methods for undertaking these analyses (e.g., ASTM D7535) rely on the use of stable lead (Pb) as a yield tracer that takes into account losses of Pb that inevitably occur during elemental/radiochemical separations of the procedures. Although effective, these methods introduce technical challenges that can be difficult to track and potentially introduce uncertainty that can be difficult to quantify. Examples of these challenges include interference from endogenous stable Pb in complex sample matrices; contamination of stable Pb carrier with Pb; and high detection limits due to counting efficiency limitations. We hypothesized that many of these challenges could be avoided by the use of the electron-capture, gamma-emitting isotope, Pb as a chemical yield tracer in the analysis of Pb. A series of experiments were performed to evaluate the efficacy of Pb as a tracer. Four different matrices were analyzed, including a complex matrix (hydraulic-fracturing produced fluids); and samples comprising less complicated matrices (i.e., river water, deionized water, and tap water). Separation techniques and counting methodologies were also compared and optimized. Due to a relatively short-half life (52 h), Pb tracer is effectively massless for the purposes of chemical separations, allowing for reduced chromatography column resin bed volumes. Because Pb is a gamma emitter (279 keV; 81% intensity), recovery can be determined non-destructively in a variety of matrices, including liquid scintillation cocktail. The use of liquid scintillation as a counting methodology allowed for determination of Pb activities via Pb or Po; and recoveries of greater than 90% are routinely achievable using this approach. The improved method for the analysis of Pb in aqueous matrices allows for the analysis of complex matrices, at reduced cost, while providing greater counting flexibility in achieving acceptable detections limits.
[Mh] Termos MeSH primário: Radioisótopos de Chumbo/análise
Monitoramento de Radiação/métodos
[Mh] Termos MeSH secundário: Limite de Detecção
Reprodutibilidade dos Testes
Contagem de Cintilação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lead Radioisotopes)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170428
[Lr] Data última revisão:
170428
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170219
[St] Status:MEDLINE


  8 / 3640 MEDLINE  
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[PMID]:28164865
[Au] Autor:Welch ML; Jaffray DA
[Ad] Endereço:Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
[Ti] Título:The correction of time and temperature effects in MR-based 3D Fricke xylenol orange dosimetry.
[So] Source:Phys Med Biol;62(8):3221-3236, 2017 Apr 21.
[Is] ISSN:1361-6560
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Previously developed MR-based three-dimensional (3D) Fricke-xylenol orange (FXG) dosimeters can provide end-to-end quality assurance and validation protocols for pre-clinical radiation platforms. FXG dosimeters quantify ionizing irradiation induced oxidation of Fe ions using pre- and post-irradiation MR imaging methods that detect changes in spin-lattice relaxation rates (R = [Formula: see text]) caused by irradiation induced oxidation of Fe . Chemical changes in MR-based FXG dosimeters that occur over time and with changes in temperature can decrease dosimetric accuracy if they are not properly characterized and corrected. This paper describes the characterization, development and utilization of an empirical model-based correction algorithm for time and temperature effects in the context of a pre-clinical irradiator and a 7 T pre-clinical MR imaging system. Time and temperature dependent changes of R values were characterized using variable TR spin-echo imaging. R -time and R -temperature dependencies were fit using non-linear least squares fitting methods. Models were validated using leave-one-out cross-validation and resampling. Subsequently, a correction algorithm was developed that employed the previously fit empirical models to predict and reduce baseline R shifts that occurred in the presence of time and temperature changes. The correction algorithm was tested on R -dose response curves and 3D dose distributions delivered using a small animal irradiator at 225 kVp. The correction algorithm reduced baseline R shifts from -2.8 × 10 s to 1.5 × 10 s . In terms of absolute dosimetric performance as assessed with traceable standards, the correction algorithm reduced dose discrepancies from approximately 3% to approximately 0.5% (2.90 ± 2.08% to 0.20 ± 0.07%, and 2.68 ± 1.84% to 0.46 ± 0.37% for the 10 × 10 and 8 × 12 mm fields, respectively). Chemical changes in MR-based FXG dosimeters produce time and temperature dependent R values for the time intervals and temperature changes found in a typical small animal imaging and irradiation laboratory setting. These changes cause baseline R shifts that negatively affect dosimeter accuracy. Characterization, modeling and correction of these effects improved in-field reported dose accuracy to less than 1% when compared to standardized ion chamber measurements.
[Mh] Termos MeSH primário: Corantes Fluorescentes/química
Fenóis/química
Contagem de Cintilação/métodos
Sulfóxidos/química
Temperatura Ambiente
[Mh] Termos MeSH secundário: Oxirredução
Contagem de Cintilação/instrumentação
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fluorescent Dyes); 0 (Phenols); 0 (Sulfoxides); S2VDY878QD (xylenol orange)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171003
[Lr] Data última revisão:
171003
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170207
[St] Status:MEDLINE
[do] DOI:10.1088/1361-6560/aa5e63


  9 / 3640 MEDLINE  
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[PMID]:28138947
[Au] Autor:Taguchi K
[Ad] Endereço:Division of Medical Imaging Physics, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 601 North Caroline Street, JHOC Room 4263, Baltimore, MD, 21287, USA. ktaguchi@jhmi.edu.
[Ti] Título:Energy-sensitive photon counting detector-based X-ray computed tomography.
[So] Source:Radiol Phys Technol;10(1):8-22, 2017 Mar.
[Is] ISSN:1865-0341
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Energy-sensitive photon counting detectors (PCDs) have recently been developed for medical X-ray computed tomography (CT) imaging and a handful of prototype PCD-CT systems have been built and evaluated. PCDs detect X-rays by using mechanisms that are completely different from the current CT detectors (i.e., energy integrating detectors or EIDs); PCDs count photons and obtain the information of the object tissues (i.e., the effective atomic numbers and mass densities) to be imaged. Therefore, these PCDs have the potential not only for evolution-to improve the current CT images such as providing dose reduction-but also for a revolution-to enable novel applications with a new concept such as molecular CT imaging. The performance of PCDs, however, is not flawless, and thus, it requires integrated efforts to develop PCD-CT for clinical use. In this article, we review the current status and the prediction for the future of PCDs, PCD-CT systems, and potential clinical applications.
[Mh] Termos MeSH primário: Fótons
Contagem de Cintilação/instrumentação
Tomografia Computadorizada por Raios X/instrumentação
[Mh] Termos MeSH secundário: Seres Humanos
Dose de Radiação
Espalhamento de Radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170201
[St] Status:MEDLINE
[do] DOI:10.1007/s12194-017-0390-9


  10 / 3640 MEDLINE  
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[PMID]:28135650
[Au] Autor:Todorovic N; Stojkovic I; Nikolov J; Tenjovic B
[Ad] Endereço:University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia. Electronic address: natasa.todorovic@df.uns.ac.rs.
[Ti] Título:Sr determination in water samples using Cerenkov radiation.
[So] Source:J Environ Radioact;169-170:197-202, 2017 Apr.
[Is] ISSN:1879-1700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A procedure for the determination of Sr in environmental water samples using Cerenkov radiation and low-level liquid scintillation counter Quantulus 1220 was applied and optimized. Low diffusion polyethylene vials, high performance glass counting vials and low potassium borosilicate glass vilas of 20 ml volume (all from PerkinElmer) were used in order to examine their potential effect on counting process. The derived efficiencies were 45.86(9)%, and a minimum detectable activity of 0.32 Bq l in a 20 ml polyethylene vial (20 ml water sample) has been achieved during 300 min of measurement. Environmental water samples might be colored and this will lead to color quenching, which one of the most important problems that affect Cerenkov is counting (Mosqueda et al., 2005). The sample channel ratio (SCR) method has been applied to correct this effect. The analytical procedures and measurement techniques were tested by participating in the IAEA-TEL-2015-03 world-wide proficiency test on determination of Sr in water sample.
[Mh] Termos MeSH primário: Monitoramento de Radiação
Radioisótopos de Estrôncio/análise
Poluentes Radioativos da Água/análise
[Mh] Termos MeSH secundário: Contagem de Cintilação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Strontium Radioisotopes); 0 (Water Pollutants, Radioactive)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170405
[Lr] Data última revisão:
170405
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170131
[St] Status:MEDLINE



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