In fluoroscopy guided interventional procedures, ceiling suspended screen is used to protect personel for scattered X-ray radiation arising from patents. The correct positioning of the screen is crucial for proper occupational radiation protection. The proposed solution in this paper provides reliable and efficient protection from scattered radiation, based on X-ray device and the protective screen merging into one system via an appropriate interface. After the initial manual positioning, automatic repositioning of the screen is ?xecuted, by curving the screen laterally, clockwise or counterclockwise, and then with the upper or lower edge forward. All potential clinical situations were analyzed, considering need for screen position correction: the semi-automatic solution is designed and realized to follow the medical procedure in order to keep the efficient level of staff radiation protection. Furthermore, the assessment of the occupational radiation dose, provided for screen position optimization, will be imported in the radiation dose structural report. With application of the universal interface, the presented solution can be applied not only on newly manufactured ones, but on existing C-arm X-ray devices as well.
{"title":"Semi - automatic positioning of the protective screen based on integration with C-arm X-ray device","authors":"M. Antić","doi":"10.2298/ntrp201210002a","DOIUrl":"https://doi.org/10.2298/ntrp201210002a","url":null,"abstract":"In fluoroscopy guided interventional procedures, ceiling suspended screen is used to protect personel for scattered X-ray radiation arising from patents. The correct positioning of the screen is crucial for proper occupational radiation protection. The proposed solution in this paper provides reliable and efficient protection from scattered radiation, based on X-ray device and the protective screen merging into one system via an appropriate interface. After the initial manual positioning, automatic repositioning of the screen is ?xecuted, by curving the screen laterally, clockwise or counterclockwise, and then with the upper or lower edge forward. All potential clinical situations were analyzed, considering need for screen position correction: the semi-automatic solution is designed and realized to follow the medical procedure in order to keep the efficient level of staff radiation protection. Furthermore, the assessment of the occupational radiation dose, provided for screen position optimization, will be imported in the radiation dose structural report. With application of the universal interface, the presented solution can be applied not only on newly manufactured ones, but on existing C-arm X-ray devices as well.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68545662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jelena Stankovic-Petrovic, Ž. Knežević, N. Kržanović, M. Majer, M. Živanović, O. Ciraj-Bjelac
Passive solid state dosimeters, such as thermoluminescence dosimeters, provide integrated measurement of the total dose and are widely used in environmental monitoring programs. The objective of this paper is to provide a comprehensive review on the use of thermoluminescent dosimetry methods for monitoring radiation dose in the environment. The article presents the part of the research results of the project PREPAREDNESS (EMPIR 2016 call for Metrology for Environment joint research project) with a particular objective to harmonize procedures used by dosimetry services, relevant authorities and Institutes across the Europe. To achieve this, different monitoring routines that are based on passive environ mental dosimetry methods are investigated. Differences in performing specific steps such as preheating, reading, annealing, minimizing fading, and others, are analyzed. The investigation was performed by means of qualitative literature review that showed the lack of information about specific steps. The conclusion of this work is that thermoluminescent dosimetry measurement system has to be type-tested even though the testing procedure is complicated. In addition to this, control dosimeters should be introduced, International Organization for Standardization protocols should be followed during calibration, and finally, parameters influencing the measurement uncertainty have to be identified and well understood in order to pro duce ac cu rate dose measurement results.
{"title":"Review of the thermoluminescent dosimetry method for the environmental dose monitoring","authors":"Jelena Stankovic-Petrovic, Ž. Knežević, N. Kržanović, M. Majer, M. Živanović, O. Ciraj-Bjelac","doi":"10.2298/ntrp2102150s","DOIUrl":"https://doi.org/10.2298/ntrp2102150s","url":null,"abstract":"Passive solid state dosimeters, such as thermoluminescence dosimeters, provide integrated measurement of the total dose and are widely used in environmental monitoring programs. The objective of this paper is to provide a comprehensive review on the use of thermoluminescent dosimetry methods for monitoring radiation dose in the environment. The article presents the part of the research results of the project PREPAREDNESS (EMPIR 2016 call for Metrology for Environment joint research project) with a particular objective to harmonize procedures used by dosimetry services, relevant authorities and Institutes across the Europe. To achieve this, different monitoring routines that are based on passive environ mental dosimetry methods are investigated. Differences in performing specific steps such as preheating, reading, annealing, minimizing fading, and others, are analyzed. The investigation was performed by means of qualitative literature review that showed the lack of information about specific steps. The conclusion of this work is that thermoluminescent dosimetry measurement system has to be type-tested even though the testing procedure is complicated. In addition to this, control dosimeters should be introduced, International Organization for Standardization protocols should be followed during calibration, and finally, parameters influencing the measurement uncertainty have to be identified and well understood in order to pro duce ac cu rate dose measurement results.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68546102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amro Obeid, B. El, Samad El, Z. Alsayed, R. Awad, M. Badawi
The X-rays of the narrow-spectrum N-series ranging from 40 kV to 150 kV were used to determine the radiation attenuation ability of a new category of a polymer composite fabricated for shielding purposes. High density polyethylene was synthesized through a compression molding technique, and incorporated with various filler amounts (10, 15, 25, and 35 wt.%) of bulk micro-sized WO 3 (Sample A), two WO 3 nanoparticles 45 nm (Sample B), and 24 nm (Sample C). The WO 3 filler was identified and characterized using X-ray diffraction and a transmission electron microscope. The mass distribution of the chemical elements of the synthesized composites was determined by energy dispersive X-ray analysis. The obtained results of the different attenuation parameters revealed that the particle size and weight fraction of WO particles have an outstanding effect on the X-ray shielding ability of this composite. The 3 experimental measurements of the mass attenuation coefficients were compared to the theoretical values tabulated in the NIST databases XCOM and FFAST. The mass attenuation coefficient was increased with the increment of WO 3 wt.% as well as with the decrease of the WO 3 particle size. This improvement in the attenuation parameters of the NP(C) composite suggests their promising applications in radiation protection at the diagnostic level.
{"title":"Effects of different nano size and bulk WO3 enriched by HDPE composites on attenuation of the X-ray narrow spectrum","authors":"Amro Obeid, B. El, Samad El, Z. Alsayed, R. Awad, M. Badawi","doi":"10.2298/ntrp2104315o","DOIUrl":"https://doi.org/10.2298/ntrp2104315o","url":null,"abstract":"The X-rays of the narrow-spectrum N-series ranging from 40 kV to 150 kV were used to determine the radiation attenuation ability of a new category of a polymer composite fabricated for shielding purposes. High density polyethylene was synthesized through a compression molding technique, and incorporated with various filler amounts (10, 15, 25, and 35 wt.%) of bulk micro-sized WO 3 (Sample A), two WO 3 nanoparticles 45 nm (Sample B), and 24 nm (Sample C). The WO 3 filler was identified and characterized using X-ray diffraction and a transmission electron microscope. The mass distribution of the chemical elements of the synthesized composites was determined by energy dispersive X-ray analysis. The obtained results of the different attenuation parameters revealed that the particle size and weight fraction of WO particles have an outstanding effect on the X-ray shielding ability of this composite. The 3 experimental measurements of the mass attenuation coefficients were compared to the theoretical values tabulated in the NIST databases XCOM and FFAST. The mass attenuation coefficient was increased with the increment of WO 3 wt.% as well as with the decrease of the WO 3 particle size. This improvement in the attenuation parameters of the NP(C) composite suggests their promising applications in radiation protection at the diagnostic level.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68546938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Milan N. Tanić, Denis Dinić, Ž. Mihaljev, B. Kartalović, M. Daković
This study aims to obtain data on terrestrial radioactivity coming from naturally occurring (40K, 226Ra, 232Th, and 238U) and artificial (137Cs) radionuclides in surface soil (0-10 cm) of selected eighteen public-access urban areas in Krusevac city, Serbia, and to assess the corresponding health effects for citizens using those areas for recreational purposes. The specific activities of investigated radionuclides were analyzed using HPGe gamma-ray spectrometry. The mean specific activity of 40K, 226Ra, 232Th, 238U, and 137Cs was found to be 353, 39.8, 38.9, 41.0, and 5.9, respectively, in compliance with their values in other parts of Serbia and neighboring countries reported in similar researches. To evaluate the human health risk associated with radionuclides, conservative exposure assumptions and models recommended by the United States Environmental Protection Agency were employed taking into account three exposure routes: ingestion, inhalation of soil, and external irradiation. The absorbed gamma dose rate in the air due to natural radionuclides in soil was calculated. The calculated indices suggested that the radiation risk arising from natural and artificial radionuclides was not significant. The total excess lifetime cancer based on the 95 % upper confidence limit of the specific activities mean was calculated to be 5.89?10?6, lower than the tolerable risk for regulatory purposes (10?4). Among investigated radiation exposure pathways, external exposure was the most contributing one for the health risk. The results obtained for the city's parks and playgrounds suggested their safe use for recreational purposes from the radioecological point of view.
{"title":"Risk assessment of human exposure to radionuclides in soil of urban areas (public parks and open playgrounds) in Krusevac, Serbia","authors":"Milan N. Tanić, Denis Dinić, Ž. Mihaljev, B. Kartalović, M. Daković","doi":"10.2298/ntrp2103271t","DOIUrl":"https://doi.org/10.2298/ntrp2103271t","url":null,"abstract":"This study aims to obtain data on terrestrial radioactivity coming from naturally occurring (40K, 226Ra, 232Th, and 238U) and artificial (137Cs) radionuclides in surface soil (0-10 cm) of selected eighteen public-access urban areas in Krusevac city, Serbia, and to assess the corresponding health effects for citizens using those areas for recreational purposes. The specific activities of investigated radionuclides were analyzed using HPGe gamma-ray spectrometry. The mean specific activity of 40K, 226Ra, 232Th, 238U, and 137Cs was found to be 353, 39.8, 38.9, 41.0, and 5.9, respectively, in compliance with their values in other parts of Serbia and neighboring countries reported in similar researches. To evaluate the human health risk associated with radionuclides, conservative exposure assumptions and models recommended by the United States Environmental Protection Agency were employed taking into account three exposure routes: ingestion, inhalation of soil, and external irradiation. The absorbed gamma dose rate in the air due to natural radionuclides in soil was calculated. The calculated indices suggested that the radiation risk arising from natural and artificial radionuclides was not significant. The total excess lifetime cancer based on the 95 % upper confidence limit of the specific activities mean was calculated to be 5.89?10?6, lower than the tolerable risk for regulatory purposes (10?4). Among investigated radiation exposure pathways, external exposure was the most contributing one for the health risk. The results obtained for the city's parks and playgrounds suggested their safe use for recreational purposes from the radioecological point of view.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68547075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Nenadovic, C. Ferone, Ljiljana M. Kljajević, M. Mirković, B. Todorović, I. Vukanac, S. Nenadović
Presented study deals with the final structure and radiological properties of different fly ash-based geopolymers. lignite fly-ash (lignite Kolubara - Serbia) and wood fly ash were obtained in combustion process together with commercial fly ash. Synthesis of the geopolymers was conducted by mixing fly ash, sodium silicate solution, NaOH and water. The samples were cured at 60?C for 48h after staying at room temperature in covering mold for 24 h. X - ray diffraction, Fourier transform infra - red and Scanning electron microscope measurements were conducted on the samples after 28 days of geopolymerization process. X-ray diffraction measurements of lignite fly ash samples show anhydrite as the main constituent, while wood fly ash samples consist of calcite, albite and gypsum minerals. Beside of determination of physical-chemical properties, the aim of this study was radiological characterization of lignite fly ash, wood fly ash and the obtained geopolymer products. Activity concentration of 40K and radionuclides from the 238U and 232Th decay series in ash samples and fly ash-based geopolymers were determined by means of gamma-ray spectrometry, and the absorbed dose rate rate (D) and the annual effective dose rate (E) were calculated in accordance with the UNSCEAR 2000 report.
{"title":"Alkali activation of different type of ash as a production of combustion process","authors":"M. Nenadovic, C. Ferone, Ljiljana M. Kljajević, M. Mirković, B. Todorović, I. Vukanac, S. Nenadović","doi":"10.2298/ntrp201120006n","DOIUrl":"https://doi.org/10.2298/ntrp201120006n","url":null,"abstract":"Presented study deals with the final structure and radiological properties of different fly ash-based geopolymers. lignite fly-ash (lignite Kolubara - Serbia) and wood fly ash were obtained in combustion process together with commercial fly ash. Synthesis of the geopolymers was conducted by mixing fly ash, sodium silicate solution, NaOH and water. The samples were cured at 60?C for 48h after staying at room temperature in covering mold for 24 h. X - ray diffraction, Fourier transform infra - red and Scanning electron microscope measurements were conducted on the samples after 28 days of geopolymerization process. X-ray diffraction measurements of lignite fly ash samples show anhydrite as the main constituent, while wood fly ash samples consist of calcite, albite and gypsum minerals. Beside of determination of physical-chemical properties, the aim of this study was radiological characterization of lignite fly ash, wood fly ash and the obtained geopolymer products. Activity concentration of 40K and radionuclides from the 238U and 232Th decay series in ash samples and fly ash-based geopolymers were determined by means of gamma-ray spectrometry, and the absorbed dose rate rate (D) and the annual effective dose rate (E) were calculated in accordance with the UNSCEAR 2000 report.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68544984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The probability of Cs+ and Co2+ ions retention by immobilization processes in the cement matrix was determinate as the subject of analyses: matrix design, water/cement ratio, and structure porosity. Comparison of experimental results was accomplished by Hespe standard leaching method. Diffusion and semi-empirical models were used for the assessment of the washing rate as a function of time. The higher value of cement matrix mechanical resistance corresponds to a lower value of Co2+ and Cs+ ions leaching. Co2+ leaching level was more than two orders of magnitude less than the leaching level of Cs+. The influence of bentonite and zeolite on Co2+ leaching reduction was significantly smaller in comparison with Cs+, while zeolite had a higher Cs+ and Co2+ sorption ability than bentonite. Under static leaching conditions, the contribution of diffusion to the total transport of ions in the matrix porous medium was dominant. The contribution of matrix dissolution was insignificant concerning the dominant contribution of diffusion and surface washing. The semi-empirical model showed a better approximation of the Co2+ and Cs+ ions laboratory leaching process.
{"title":"Influence of bentonite and zeolite on Cs+ and Co2+ cement matrix leaching phenomena","authors":"S. Dimović, I. Jelić, M. Šljivić-Ivanović","doi":"10.2298/ntrp201130003d","DOIUrl":"https://doi.org/10.2298/ntrp201130003d","url":null,"abstract":"The probability of Cs+ and Co2+ ions retention by immobilization processes in the cement matrix was determinate as the subject of analyses: matrix design, water/cement ratio, and structure porosity. Comparison of experimental results was accomplished by Hespe standard leaching method. Diffusion and semi-empirical models were used for the assessment of the washing rate as a function of time. The higher value of cement matrix mechanical resistance corresponds to a lower value of Co2+ and Cs+ ions leaching. Co2+ leaching level was more than two orders of magnitude less than the leaching level of Cs+. The influence of bentonite and zeolite on Co2+ leaching reduction was significantly smaller in comparison with Cs+, while zeolite had a higher Cs+ and Co2+ sorption ability than bentonite. Under static leaching conditions, the contribution of diffusion to the total transport of ions in the matrix porous medium was dominant. The contribution of matrix dissolution was insignificant concerning the dominant contribution of diffusion and surface washing. The semi-empirical model showed a better approximation of the Co2+ and Cs+ ions laboratory leaching process.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68545535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Stefanović, Nikola Krunić, Nataša Danilović-Hristić
In the Republic of Serbia, radioactive waste has been stored for many years at the Vinca location near Belgrade. However, the location is not suitable for this purpose. It is necessary to define a location for radioactive waste disposal in Serbia in accordance with international criteria, strict spatial conditions and planning solutions of national interest. The need to conduct research that will define potential zones for radioactive waste disposal is the basic starting point in this paper. The framework of the research is the development of the Spatial Plan of the Republic of Serbia from 2021 to 2035, on the basis of which it is possible to determine potential zones for the construction of a radioactive waste disposal. In this paper, the authors present the results of research on spatial constraints from the aspects of geological and hydrological conditions, spatial protection, and distribution of the population, settlements and buildings, etc. A special contribution it makes is the additional analysis of conditionality in relation to the planned purposes and activities of national and priority importance in Serbia. The collection, processing and presentation of spatial data is the result of analyses conducted with the support of geographic information systems. The research contributes to a definition of potential zones, within the scope of which it is necessary to conduct further research and select the optimal location for a radioactive waste disposal. The paper provides methodological guidelines for further scientific research into the spatial aspects of radioactive waste disposal in Serbia, at the same time pointing out possible directions for further resolution of this issue in practice.
{"title":"The spatial and planning aspect of solving the issue of radioactive waste disposal in the Republic of Serbia","authors":"N. Stefanović, Nikola Krunić, Nataša Danilović-Hristić","doi":"10.2298/ntrp210119011s","DOIUrl":"https://doi.org/10.2298/ntrp210119011s","url":null,"abstract":"In the Republic of Serbia, radioactive waste has been stored for many years at the Vinca location near Belgrade. However, the location is not suitable for this purpose. It is necessary to define a location for radioactive waste disposal in Serbia in accordance with international criteria, strict spatial conditions and planning solutions of national interest. The need to conduct research that will define potential zones for radioactive waste disposal is the basic starting point in this paper. The framework of the research is the development of the Spatial Plan of the Republic of Serbia from 2021 to 2035, on the basis of which it is possible to determine potential zones for the construction of a radioactive waste disposal. In this paper, the authors present the results of research on spatial constraints from the aspects of geological and hydrological conditions, spatial protection, and distribution of the population, settlements and buildings, etc. A special contribution it makes is the additional analysis of conditionality in relation to the planned purposes and activities of national and priority importance in Serbia. The collection, processing and presentation of spatial data is the result of analyses conducted with the support of geographic information systems. The research contributes to a definition of potential zones, within the scope of which it is necessary to conduct further research and select the optimal location for a radioactive waste disposal. The paper provides methodological guidelines for further scientific research into the spatial aspects of radioactive waste disposal in Serbia, at the same time pointing out possible directions for further resolution of this issue in practice.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68545566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ljiljana M. Kljajević, M. Mirković, S. Dolenec, Katarina Šter, M. Hadžalić, I. Vukanac, M. Nenadovic
The potential re-use of red mud in the building and construction industry has been the subject of research of many scientists. The presented research is a contribution to the potential solution of this environmental issue through the synthesis of potential construction materials based on red mud. A promising way of recycling these secondary raw materials is the synthesis of alkali-activated binders or alkali activated materials. Alkali-activated materials or inorganic binders based on red mud are a new class of materials obtained by activation of inorganic precursors mainly constituted by silica, alumina and low content of calcium oxide. Since red mud contains radioactive elements like 226Ra and 232Th, this may be a problem for its further utilization. The content of naturally occurring radionuclides in manufactured material products with potential application in the building and construction industry is important from the standpoint of radiation protection. Gamma radiation of the primordial radionuclides, 40K and members of the uranium and thorium series, increases the external gamma dose rate. However, more and more precedence is being given to limiting the radiological dose originating from building materials on the population these days. The aim of this research was to investigate the possible influence of alkali activation-polymerization processes on the natural radioactivity of alkali activated materials synthesized by red mud (BOKSIT a. d. Milici, Zvornik, Bosnia and Herzegovina) and their structural properties. This research confirmed that during the polymerization process the natural radioactivity was reduced, and that the process of alkali activation of raw materials has an influence on natural radioactivity of synthesized materials.
{"title":"Radiological and physico-chemical characterization of red mud as an Al-containing precursor in inorganic binders for the building industry","authors":"Ljiljana M. Kljajević, M. Mirković, S. Dolenec, Katarina Šter, M. Hadžalić, I. Vukanac, M. Nenadovic","doi":"10.2298/ntrp2102182k","DOIUrl":"https://doi.org/10.2298/ntrp2102182k","url":null,"abstract":"The potential re-use of red mud in the building and construction industry has been the subject of research of many scientists. The presented research is a contribution to the potential solution of this environmental issue through the synthesis of potential construction materials based on red mud. A promising way of recycling these secondary raw materials is the synthesis of alkali-activated binders or alkali activated materials. Alkali-activated materials or inorganic binders based on red mud are a new class of materials obtained by activation of inorganic precursors mainly constituted by silica, alumina and low content of calcium oxide. Since red mud contains radioactive elements like 226Ra and 232Th, this may be a problem for its further utilization. The content of naturally occurring radionuclides in manufactured material products with potential application in the building and construction industry is important from the standpoint of radiation protection. Gamma radiation of the primordial radionuclides, 40K and members of the uranium and thorium series, increases the external gamma dose rate. However, more and more precedence is being given to limiting the radiological dose originating from building materials on the population these days. The aim of this research was to investigate the possible influence of alkali activation-polymerization processes on the natural radioactivity of alkali activated materials synthesized by red mud (BOKSIT a. d. Milici, Zvornik, Bosnia and Herzegovina) and their structural properties. This research confirmed that during the polymerization process the natural radioactivity was reduced, and that the process of alkali activation of raw materials has an influence on natural radioactivity of synthesized materials.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68546165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Teodora Nedić, D. Lazarevic, K. Stanković, N. Kartalović
This paper considered the possibility of reducing the dissipation of the trigger time of the three-electrode spark gaps with a separated triggered electrode. The work is of a theoretical, numerical and of experimental nature. The experiments were performed on a spark gap model under well-controlled laboratory conditions. It was determined that the results obtained with the model can be applied to the spark gap prototype. Unlike the previous research in this area, the computer-designed spark gap that was used can be triggered with one mechanism only. Also, as opposed to the previous study, a mixture of SF6 and He gases and the third electrode with a double ionization effect were used. The obtained results showed the optimal combination of the construction solution, insulation gas, triggered impulse, and the triggered electrode's shape, reduce the stochastic dissipation of a random variable far in the sub-microsecond field. This result is of great significance for the parallel triggering of current and voltage generators to obtain the best superposition signals.
{"title":"Optimization of fast three-electrode spark gaps isolated with a SF6 and he mixture","authors":"Teodora Nedić, D. Lazarevic, K. Stanković, N. Kartalović","doi":"10.2298/ntrp2103234n","DOIUrl":"https://doi.org/10.2298/ntrp2103234n","url":null,"abstract":"This paper considered the possibility of reducing the dissipation of the trigger time of the three-electrode spark gaps with a separated triggered electrode. The work is of a theoretical, numerical and of experimental nature. The experiments were performed on a spark gap model under well-controlled laboratory conditions. It was determined that the results obtained with the model can be applied to the spark gap prototype. Unlike the previous research in this area, the computer-designed spark gap that was used can be triggered with one mechanism only. Also, as opposed to the previous study, a mixture of SF6 and He gases and the third electrode with a double ionization effect were used. The obtained results showed the optimal combination of the construction solution, insulation gas, triggered impulse, and the triggered electrode's shape, reduce the stochastic dissipation of a random variable far in the sub-microsecond field. This result is of great significance for the parallel triggering of current and voltage generators to obtain the best superposition signals.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68546695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The value of personal dose equivalent at10 mm depth is to characterize the energy deposition of strong penetrating radiation in human body and is derived by measurement of air kerma and application of conversion coefficients from ISO report. However, the conversion coefficients depend strongly on the photon energy and angles of incidence for low-energy photons. In order to overcome the problem that the conversion coefficient of low energy rays changes greatly due to the small change of energy, a secondary standard ionization chamber was used to measure personal dose equivalent directly. A matched reference field was established with (20-250) kV X-rays and correction factors with Hp(10) chamber were calculated under these radiation qualities with different angles of incidence. The results showed that the differences were almost 22.7 % of correction factors for the low energy photons at angles of incidence 0?. With conversion coefficient recommended in ISO 4037-3-2019, performance of the chamber response with respect to Hp(10) in the energy range from 33 keV to 208 keV was within about ?10%, and in the energy range from 12 keV to 208 keV and for angles of incidence between 0? and 75? was within about ?19%.
{"title":"Calibration and measurement of X-ray personal dose equivalent with a Hp(10) ionization chamber","authors":"Yang Xu, Rui Zhao","doi":"10.2298/ntrp210304019x","DOIUrl":"https://doi.org/10.2298/ntrp210304019x","url":null,"abstract":"The value of personal dose equivalent at10 mm depth is to characterize the energy deposition of strong penetrating radiation in human body and is derived by measurement of air kerma and application of conversion coefficients from ISO report. However, the conversion coefficients depend strongly on the photon energy and angles of incidence for low-energy photons. In order to overcome the problem that the conversion coefficient of low energy rays changes greatly due to the small change of energy, a secondary standard ionization chamber was used to measure personal dose equivalent directly. A matched reference field was established with (20-250) kV X-rays and correction factors with Hp(10) chamber were calculated under these radiation qualities with different angles of incidence. The results showed that the differences were almost 22.7 % of correction factors for the low energy photons at angles of incidence 0?. With conversion coefficient recommended in ISO 4037-3-2019, performance of the chamber response with respect to Hp(10) in the energy range from 33 keV to 208 keV was within about ?10%, and in the energy range from 12 keV to 208 keV and for angles of incidence between 0? and 75? was within about ?19%.","PeriodicalId":49734,"journal":{"name":"Nuclear Technology & Radiation Protection","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68546827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：