One of the six selected concepts to be part of Generation IV nuclear reactors is the Supercritical Light Water Cooled Reactor. The High-Performance Light Water Reactor (HPLWR) is the European version and it is a very promising design. In recent years, interest in the study of thorium-based fuel cycles has been renewed and its possibilities for current LWRs have been evaluated. The use of thorium-based fuels will be fundamental in the future sustainability of nuclear energy, since in addition to its abundance in nature, thorium has an important group of advantages. In this paper, performance of thorium-based fuels in the typical fuel assembly of the HPLWR reactor is evaluated, using a computational model based on CFD and Monte Carlo codes for the neutronic/thermal-hydraulic coupled analysis. The volumetric power density profiles, coolant temperature profiles, fuel temperature profiles and others are compared with those obtained for standard UO 2 fuel. When the thorium-based fuels are used, the obtained infinite multiplication coefficients are smaller than the value obtained when UO 2 is used, since the 232 Th isotope has a lower contribution to the multiplicative properties of the medium than 238 U. As a result, a difference of approximately 12 000 pcm was observed. The results verified that the HPLWR is a thermal reactor with a hard spectrum. There are no notable changes in the neutron spectrum if the mass fraction of thorium is slightly varied. With coupled analysis, the potential benefits of the utilization of thorium-based fuels were verified. Moreover, a significant temperature decrease by 136 K on the center line of the fuel elements was observed. When the mass fraction of thorium increases in the oxides mixture, the weighted average temperature on the fuel elements decreases .
{"title":"Coupled Analysis of Thorium-based Fuels in the High-Performance Light Water Reactor Fuel Assembly","authors":"Y. Pérez, C. R. García, F. Mena, L. Castro","doi":"10.17146/aij.2021.1081","DOIUrl":"https://doi.org/10.17146/aij.2021.1081","url":null,"abstract":"One of the six selected concepts to be part of Generation IV nuclear reactors is the Supercritical Light Water Cooled Reactor. The High-Performance Light Water Reactor (HPLWR) is the European version and it is a very promising design. In recent years, interest in the study of thorium-based fuel cycles has been renewed and its possibilities for current LWRs have been evaluated. The use of thorium-based fuels will be fundamental in the future sustainability of nuclear energy, since in addition to its abundance in nature, thorium has an important group of advantages. In this paper, performance of thorium-based fuels in the typical fuel assembly of the HPLWR reactor is evaluated, using a computational model based on CFD and Monte Carlo codes for the neutronic/thermal-hydraulic coupled analysis. The volumetric power density profiles, coolant temperature profiles, fuel temperature profiles and others are compared with those obtained for standard UO 2 fuel. When the thorium-based fuels are used, the obtained infinite multiplication coefficients are smaller than the value obtained when UO 2 is used, since the 232 Th isotope has a lower contribution to the multiplicative properties of the medium than 238 U. As a result, a difference of approximately 12 000 pcm was observed. The results verified that the HPLWR is a thermal reactor with a hard spectrum. There are no notable changes in the neutron spectrum if the mass fraction of thorium is slightly varied. With coupled analysis, the potential benefits of the utilization of thorium-based fuels were verified. Moreover, a significant temperature decrease by 136 K on the center line of the fuel elements was observed. When the mass fraction of thorium increases in the oxides mixture, the weighted average temperature on the fuel elements decreases .","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46162400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Nitasari, C. Anam, W. Budi, A. L. Wati, S. Syarifudin, G. Dougherty
Normal 0 false false false EN-ID JA AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman",serif; mso-ansi-language:EN-ID;} The size-specific dose estimate (SSDE) is a metric for an estimation of patient dose in computed tomography (CT). The SSDE strongly depends on the water-equivalent diameter (D W ). In abdominal CT examinations, a contrast agent is sometimes used to more clearly visualize tissue lesions. The Hounsfield unit (HU) of CT images with and without the use of a contrast agent at specific areas is slightly different and it may affect the D W value. This study aimed to compare the D W values calculated from axial CT images in patients who had undergone routine abdominal scans both with and without the use of a contrast agent. Axial images of 144 patients with a weight range of 3.5 kg to 90 kg who had undergone routine abdominal scans both with and without the use of a contrast agent using a Siemens Sensation 64 CT scanner were retrospectively collected. The D W values were automatically calculated using the Matlab-based IndoseCT (version 15a) software. The results show the percentage difference between D W,contrast and D W,non - contrast is below 2 %. As a result, the mean SSDE contrast is 1.5 % smaller than SSDE non - contrast . Due to the effect of a contrast agent on the D W and SSDE value s is below 2 %, the axial images of CT abdomen without the use of a contrast agent can be used as the accurate estimation of D W and SSDE for images with the use of a contrast agent. Normal 0 false false false EN-ID JA AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif"; mso-ansi-language:EN-ID; mso-fareast-language:EN-US;}
{"title":"Comparisons of Water-Equivalent Diameter Measured on Images of Abdominal Routine Computed Tomography with and without A Contrast Agent","authors":"A. Nitasari, C. Anam, W. Budi, A. L. Wati, S. Syarifudin, G. Dougherty","doi":"10.17146/aij.2021.1112","DOIUrl":"https://doi.org/10.17146/aij.2021.1112","url":null,"abstract":"Normal 0 false false false EN-ID JA AR-SA /* Style Definitions */ \u0000 table.MsoNormalTable \u0000 {mso-style-name:\"Table Normal\"; \u0000 mso-tstyle-rowband-size:0; \u0000 mso-tstyle-colband-size:0; \u0000 mso-style-noshow:yes; \u0000 mso-style-priority:99; \u0000 mso-style-parent:\"\"; \u0000 mso-padding-alt:0cm 5.4pt 0cm 5.4pt; \u0000 mso-para-margin:0cm; \u0000 mso-para-margin-bottom:.0001pt; \u0000 mso-pagination:widow-orphan; \u0000 font-size:10.0pt; \u0000 font-family:\"Times New Roman\",serif; \u0000 mso-ansi-language:EN-ID;} \u0000 The size-specific dose estimate (SSDE) is a metric for an estimation of patient dose in computed tomography (CT). The SSDE strongly depends on the water-equivalent diameter (D W ). In abdominal CT examinations, a contrast agent is sometimes used to more clearly visualize tissue lesions. The Hounsfield unit (HU) of CT images with and without the use of a contrast agent at specific areas is slightly different and it may affect the D W value. This study aimed to compare the D W values calculated from axial CT images in patients who had undergone routine abdominal scans both with and without the use of a contrast agent. Axial images of 144 patients with a weight range of 3.5 kg to 90 kg who had undergone routine abdominal scans both with and without the use of a contrast agent using a Siemens Sensation 64 CT scanner were retrospectively collected. The D W values were automatically calculated using the Matlab-based IndoseCT (version 15a) software. The results show the percentage difference between D W,contrast and D W,non - contrast is below 2 %. As a result, the mean SSDE contrast is 1.5 % smaller than SSDE non - contrast . Due to the effect of a contrast agent on the D W and SSDE value s is below 2 %, the axial images of CT abdomen without the use of a contrast agent can be used as the accurate estimation of D W and SSDE for images with the use of a contrast agent. Normal 0 false false false EN-ID JA AR-SA /* Style Definitions */ \u0000 table.MsoNormalTable \u0000 {mso-style-name:\"Table Normal\"; \u0000 mso-tstyle-rowband-size:0; \u0000 mso-tstyle-colband-size:0; \u0000 mso-style-noshow:yes; \u0000 mso-style-priority:99; \u0000 mso-style-parent:\"\"; \u0000 mso-padding-alt:0cm 5.4pt 0cm 5.4pt; \u0000 mso-para-margin:0cm; \u0000 mso-para-margin-bottom:.0001pt; \u0000 mso-pagination:widow-orphan; \u0000 font-size:10.0pt; \u0000 font-family:\"Times New Roman\",\"serif\"; \u0000 mso-ansi-language:EN-ID; \u0000 mso-fareast-language:EN-US;}","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43049374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Sofiyatun, C. Anam, Ummu Mar'atu Zahro, D. A. Rukmana, G. Dougherty
Measurement of the slice thickness in computed tomography (CT) is usually made using a special phantom, such as the AAPM CT performance phantom. Images of the phantom are analyzed manually and subjectively. The purpose of this study is to develop an automated system for measuring the slice thickness of the CT image of the phantom using MATLAB software. The CT AAPM performance phantom was scanned by a 128 multi-slice computed tomography scanner (Revolution Evo, GE Healthcare, Waukesha, WI) at a slice thickness of 5 mm with four different phantom orientations and also scanned by a 6 multi-slice CT scanner (Somatom Emotion 6, Siemens AG, Forchheim, Germany) for two slice thicknesses of 5 and 10 mm. Our automat ed method produce d an accurate slice thickness value less than 0.5 mm different from the nominal slice thicknesses and manual measurements. Similar results were obtained when the phantom was rotated. This system is more objective and effective compared to manual systems.
{"title":"An Automated Measurement of Image Slice Thickness of Computed Tomography","authors":"S. Sofiyatun, C. Anam, Ummu Mar'atu Zahro, D. A. Rukmana, G. Dougherty","doi":"10.17146/aij.2021.1111","DOIUrl":"https://doi.org/10.17146/aij.2021.1111","url":null,"abstract":"Measurement of the slice thickness in computed tomography (CT) is usually made using a special phantom, such as the AAPM CT performance phantom. Images of the phantom are analyzed manually and subjectively. The purpose of this study is to develop an automated system for measuring the slice thickness of the CT image of the phantom using MATLAB software. The CT AAPM performance phantom was scanned by a 128 multi-slice computed tomography scanner (Revolution Evo, GE Healthcare, Waukesha, WI) at a slice thickness of 5 mm with four different phantom orientations and also scanned by a 6 multi-slice CT scanner (Somatom Emotion 6, Siemens AG, Forchheim, Germany) for two slice thicknesses of 5 and 10 mm. Our automat ed method produce d an accurate slice thickness value less than 0.5 mm different from the nominal slice thicknesses and manual measurements. Similar results were obtained when the phantom was rotated. This system is more objective and effective compared to manual systems.","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45832716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ι-Carrageenan is a biodegradable and biocompatible biomaterial which potentially stabilizes colloidal silver nanoparticles (AgNPs). The present study explored gamma radiosynthesis of AgNPs at varied concentration of ι-carrageenan solutions. The reaction system contained 1.0 mM silver precursor from silver nitrate salt. Gamma irradiation was conducted at doses up to 20 kGy under simple condition, i.e., atmospheric gases and without addition of hydroxyl radical scavenger. The behavior of AgNPs in suspension was characterized based on their surface plasmon resonance (SPR) absorption spectra which were measured using UV-vis spectrophotometer. The results show that colloidal AgNPs were successfully radiosynthesized due to dual stabilizing/reducing activity of ι-carrageenan. The degradation product of ι-carrageenan shows antioxidant activities, which increase the reducing condition of the reaction system. TEM micrograph reveals that the nanoparticles are spheroid in shape and monodisperse with an average particle size of below 10 nm. The SPR spectra indicate that the highest AgNPs concentration is found for irradiation at a dose of 10 kGy and ι-carrageenan concentration of 1.0 % (w/v). However, instability of AgNPs occurred a day after radiosynthesis due to oxidative dissolution and agglomeration. Further works on pH adjustment and optimization on irradiation dose and ι-carrageenan concentration are critical to improve the stability of colloidal AgNPs. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}
{"title":"Gamma Radiosynthesis of Colloidal Silver Nanoparticles Stabilized in ι-Carrageenan Under Atmospheric Gases: A Surface Plasmon Resonance Based Study","authors":"D. Perkasa, M. Yunus, Y. Warastuti, B. Abbas","doi":"10.17146/aij.2021.963","DOIUrl":"https://doi.org/10.17146/aij.2021.963","url":null,"abstract":"ι-Carrageenan is a biodegradable and biocompatible biomaterial which potentially stabilizes colloidal silver nanoparticles (AgNPs). The present study explored gamma radiosynthesis of AgNPs at varied concentration of ι-carrageenan solutions. The reaction system contained 1.0 mM silver precursor from silver nitrate salt. Gamma irradiation was conducted at doses up to 20 kGy under simple condition, i.e., atmospheric gases and without addition of hydroxyl radical scavenger. The behavior of AgNPs in suspension was characterized based on their surface plasmon resonance (SPR) absorption spectra which were measured using UV-vis spectrophotometer. The results show that colloidal AgNPs were successfully radiosynthesized due to dual stabilizing/reducing activity of ι-carrageenan. The degradation product of ι-carrageenan shows antioxidant activities, which increase the reducing condition of the reaction system. TEM micrograph reveals that the nanoparticles are spheroid in shape and monodisperse with an average particle size of below 10 nm. The SPR spectra indicate that the highest AgNPs concentration is found for irradiation at a dose of 10 kGy and ι-carrageenan concentration of 1.0 % (w/v). However, instability of AgNPs occurred a day after radiosynthesis due to oxidative dissolution and agglomeration. Further works on pH adjustment and optimization on irradiation dose and ι-carrageenan concentration are critical to improve the stability of colloidal AgNPs. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ \u0000 table.MsoNormalTable \u0000 {mso-style-name:\"Table Normal\"; \u0000 mso-tstyle-rowband-size:0; \u0000 mso-tstyle-colband-size:0; \u0000 mso-style-noshow:yes; \u0000 mso-style-priority:99; \u0000 mso-style-parent:\"\"; \u0000 mso-padding-alt:0cm 5.4pt 0cm 5.4pt; \u0000 mso-para-margin:0cm; \u0000 mso-para-margin-bottom:.0001pt; \u0000 mso-pagination:widow-orphan; \u0000 font-size:10.0pt; \u0000 font-family:\"Times New Roman\",\"serif\";}","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48663034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Afrianti, D. Tahir, B. Y. E. B. Jumpeno, O. A. Firmansyah, J. Mellawati
Radiation shield ing aprons are needed by radiation workers to minimize radiation exposure to the body. The apron s at present use fabric-coated lead plates which are heavy and rigid materials and therefore are not comfortable to use. Polymer aprons from cassava starch and glycerin with addition of Pb- nitrate filler at 0 %, 2 %, 4 %, and 6 % have been synthesized. Mixtures for synthesizing the polymer apron composites were heated using a magnetic stirrer at a speed of 800 rpm at 160 °C for 25 minutes. Then, the polymer apron composites were dried in an oven for 24 hours at 70 °C. The effectiveness of the apron was determined by calculating the attenuation coefficient ( μ ), half-value layer (HVL), and radiation absorption. The mechanical properties of the aprons were characterized by testing their tensile strengths using an A&D MCT-2150 universal tester. The result shows that the optimal addition of Pb- nitrate filler of as much as 6 % produced aprons with an attenuation coefficient of 1248 cm ‑1 , HVL of 0.54 cm, and radiation absorption of 25 % , while the aprons’ tensile strength was obtained as 28.244 MPa. T he addition of Pb-nitrate as a filler in apron composites proportionally improves the quality of materials used as radiation shields. More detailed research is still needed to obtain the best apron. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}
{"title":"Addition of Lead (Pb)-Nitrate Filler on Polymer Composite Aprons for X-Ray Radiation Shielding","authors":"E. Afrianti, D. Tahir, B. Y. E. B. Jumpeno, O. A. Firmansyah, J. Mellawati","doi":"10.17146/aij.2021.1033","DOIUrl":"https://doi.org/10.17146/aij.2021.1033","url":null,"abstract":"Radiation shield ing aprons are needed by radiation workers to minimize radiation exposure to the body. The apron s at present use fabric-coated lead plates which are heavy and rigid materials and therefore are not comfortable to use. Polymer aprons from cassava starch and glycerin with addition of Pb- nitrate filler at 0 %, 2 %, 4 %, and 6 % have been synthesized. Mixtures for synthesizing the polymer apron composites were heated using a magnetic stirrer at a speed of 800 rpm at 160 °C for 25 minutes. Then, the polymer apron composites were dried in an oven for 24 hours at 70 °C. The effectiveness of the apron was determined by calculating the attenuation coefficient ( μ ), half-value layer (HVL), and radiation absorption. The mechanical properties of the aprons were characterized by testing their tensile strengths using an A&D MCT-2150 universal tester. The result shows that the optimal addition of Pb- nitrate filler of as much as 6 % produced aprons with an attenuation coefficient of 1248 cm ‑1 , HVL of 0.54 cm, and radiation absorption of 25 % , while the aprons’ tensile strength was obtained as 28.244 MPa. T he addition of Pb-nitrate as a filler in apron composites proportionally improves the quality of materials used as radiation shields. More detailed research is still needed to obtain the best apron. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ \u0000 table.MsoNormalTable \u0000 {mso-style-name:\"Table Normal\"; \u0000 mso-tstyle-rowband-size:0; \u0000 mso-tstyle-colband-size:0; \u0000 mso-style-noshow:yes; \u0000 mso-style-priority:99; \u0000 mso-style-parent:\"\"; \u0000 mso-padding-alt:0cm 5.4pt 0cm 5.4pt; \u0000 mso-para-margin-top:0cm; \u0000 mso-para-margin-right:0cm; \u0000 mso-para-margin-bottom:10.0pt; \u0000 mso-para-margin-left:0cm; \u0000 line-height:115%; \u0000 mso-pagination:widow-orphan; \u0000 font-size:11.0pt; \u0000 font-family:\"Calibri\",\"sans-serif\"; \u0000 mso-ascii-font-family:Calibri; \u0000 mso-ascii-theme-font:minor-latin; \u0000 mso-hansi-font-family:Calibri; \u0000 mso-hansi-theme-font:minor-latin; \u0000 mso-bidi-font-family:\"Times New Roman\"; \u0000 mso-bidi-theme-font:minor-bidi;}","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48600022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
During Computed Tomography (CT) scan examinations, it is important to ensure a good diagnosis by providing the maximum information to detect pathologies and this can be done with a reduced dose. In this respect, several methods of dose reduction have been studied and evaluated. This work investigates the effect of tube voltage while varying the tube current on image quality and radiation dose at Chest CT examination. This study was conducted on HITACHI CT 16 slice Scanner using two phantoms for evaluating the dose and image quality; a PMMA phantom and a CATPHAN 500. Two tube voltages of 120 KVp and 100 KVp have been used for some variation of the tube currents (mAs) and recording the values of the measured quantities (CTDIv, spatial resolution, contrast to noise ratio CNR and noise). The scanning with 100 KVp at Chest CT examination led to a reduction in CTDIv until 45 %, an increase of noise from 17 % to 45 %, and the Spatial Resolution fell slightly (6 and 7 pl/cm) compared to the 120 KVp. The CNR shows a slight regression from 11 to 22 % for the 120 KVp and 100 KVp. This study has shown that despite the increase in the image noise at low tube voltage 100 KVp, it is possible to reduce the radiation dose by up to 45 % without degradation of image quality at Chest CT examination. Further works will evaluate the effect of acquisition parameters in other CT examinations.
{"title":"Impact of Tube Voltage on Radiation Dose (CTDI) and Image Quality at Chest CT Examination","authors":"M. E. Mansouri, A. Choukri, M. Talbi, O. Hakam","doi":"10.17146/aij.2021.1120","DOIUrl":"https://doi.org/10.17146/aij.2021.1120","url":null,"abstract":"During Computed Tomography (CT) scan examinations, it is important to ensure a good diagnosis by providing the maximum information to detect pathologies and this can be done with a reduced dose. In this respect, several methods of dose reduction have been studied and evaluated. This work investigates the effect of tube voltage while varying the tube current on image quality and radiation dose at Chest CT examination. This study was conducted on HITACHI CT 16 slice Scanner using two phantoms for evaluating the dose and image quality; a PMMA phantom and a CATPHAN 500. Two tube voltages of 120 KVp and 100 KVp have been used for some variation of the tube currents (mAs) and recording the values of the measured quantities (CTDIv, spatial resolution, contrast to noise ratio CNR and noise). The scanning with 100 KVp at Chest CT examination led to a reduction in CTDIv until 45 %, an increase of noise from 17 % to 45 %, and the Spatial Resolution fell slightly (6 and 7 pl/cm) compared to the 120 KVp. The CNR shows a slight regression from 11 to 22 % for the 120 KVp and 100 KVp. This study has shown that despite the increase in the image noise at low tube voltage 100 KVp, it is possible to reduce the radiation dose by up to 45 % without degradation of image quality at Chest CT examination. Further works will evaluate the effect of acquisition parameters in other CT examinations.","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46652224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Zulfa, S. Yuliawati, M. Martini, R. Hestiningsih, B. Ernawan
Aedes aegypti is currently emerging as a main vector of Dengue, Zika, and Chikungunya transmission. Chemical control was reported to be less effective due to the resistance of this mosquito to some types of insecticides. Therefore, another vector control is needed which is most appropriate to be used, i.e. the sterile insect technique (SIT). Information about optimum range dispersal sterile male Aedes aegypti for optimalization SIT program are needed. This study was designed to determine the dispersal pattern and population estimation of Aedes aegypti sterilized with gamma rays using mark-release-recapture (MRR) method. After the male Aedes aegypti (pupal stage) was irradiated with 70 Gy of gamma rays, the mosquitoes were then marked with Rhodamine-B and released into the study site. MRR experiments were carried out in Batan Indah residential area, and the Aedes aegypti were released in center of the site. Mosquitoes were recaptured at 28 points spread over the Batan Indah Residence for 2, 4, 6, and 8 days after release by using BG-Sentinel Traps. The result showed that the population of Aedes aegypti in the site was estimated to be 5.402 (1.347–14.636; CI 95 %) with the furthest spread distance was 119 meters from the release point. This study also showed that the MRR experiment can be used to estimate the population size and dispersal pattern of Aedes aegypti movement in a given locality. The result of present study provide better understanding for optimalization mosquito-borne disease prevention based on SIT programs.
{"title":"Estimation of Population Size and Dispersal Pattern of Sterile Male Aedes aegypti Using Mark-Release-Recapture (MRR)","authors":"R. Zulfa, S. Yuliawati, M. Martini, R. Hestiningsih, B. Ernawan","doi":"10.17146/AIJ.2021.1052","DOIUrl":"https://doi.org/10.17146/AIJ.2021.1052","url":null,"abstract":"Aedes aegypti is currently emerging as a main vector of Dengue, Zika, and Chikungunya transmission. Chemical control was reported to be less effective due to the resistance of this mosquito to some types of insecticides. Therefore, another vector control is needed which is most appropriate to be used, i.e. the sterile insect technique (SIT). Information about optimum range dispersal sterile male Aedes aegypti for optimalization SIT program are needed. This study was designed to determine the dispersal pattern and population estimation of Aedes aegypti sterilized with gamma rays using mark-release-recapture (MRR) method. After the male Aedes aegypti (pupal stage) was irradiated with 70 Gy of gamma rays, the mosquitoes were then marked with Rhodamine-B and released into the study site. MRR experiments were carried out in Batan Indah residential area, and the Aedes aegypti were released in center of the site. Mosquitoes were recaptured at 28 points spread over the Batan Indah Residence for 2, 4, 6, and 8 days after release by using BG-Sentinel Traps. The result showed that the population of Aedes aegypti in the site was estimated to be 5.402 (1.347–14.636; CI 95 %) with the furthest spread distance was 119 meters from the release point. This study also showed that the MRR experiment can be used to estimate the population size and dispersal pattern of Aedes aegypti movement in a given locality. The result of present study provide better understanding for optimalization mosquito-borne disease prevention based on SIT programs.","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49406100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diffusion approximation is an important approximation used to model a nuclear reactor core with a quite good accuracy and less computational cost. This approximation has been used widely around the globe for various kinds of nuclear reactors. This diffusion approximation is applied in a two-step method, a method combining a high fidelity transport code and low fidelity diffusion code. Meanwhile, innovations in the nuclear core model continue to make the nuclear reactor core safer, more robust, and smaller. The trend of creating smaller and more modular reactor core is emerging in the last ten years. These innovations will affect the core modeling system. Consequently, for smaller reactors, it is important to evaluate the capability of diffusion approximation if one wants to use a computationally cheaper method to model the reactor core. In this paper, neutron diffusion calculation for 160 MWth integral pressurized water reactor (IPWR) core was conducted using the PARCS nodal diffusion code employing the few-group spatially homogenized cross-sections generated by the Serpent Monte Carlo code. Due to its capability to model any reactor geometry in the high-resolution calculation, the results from Serpent were also used as a reference. Two important parameters are compared between PARCS and Serpent: effective neutron multiplication factor and core power distribution. For the full IPWR core model, a discrepancy of 564 pcm between PARCS and Serpent k eff was observed, while the radial power distribution had a maximum error of 4.71 %. It can be said, to some extent, that the diffusion approximation can be applied to IPWR core analysis. However, further improvement is indeed required if one wants more accurate results with low computational costs.
扩散近似是一种重要的核反应堆堆芯建模方法，具有较好的精度和较低的计算成本。这种近似已在全球范围内广泛用于各种核反应堆。这种扩散近似应用于两步方法，一种结合高保真传输码和低保真扩散码的方法。与此同时，堆芯模型的创新继续使核反应堆堆芯更安全、更坚固、更小。近十年来出现了制造更小、更模块化反应堆堆芯的趋势。这些创新将影响核心建模系统。因此，对于较小的反应堆，如果想使用计算成本更低的方法来模拟反应堆堆芯，评估扩散近似的能力是很重要的。本文采用PARCS节点扩散程序，利用Serpent蒙特卡罗程序生成的少数群空间均匀化截面，对160 mw整体压水堆(IPWR)堆芯进行了中子扩散计算。由于它能够在高分辨率计算中模拟任何反应堆几何形状，因此Serpent的结果也被用作参考。PARCS和Serpent的两个重要参数:有效中子倍增系数和堆芯功率分布进行了比较。对于完整的IPWR核心模型，PARCS与Serpent k - eff之间的误差为564 pcm，而径向功率分布的最大误差为4.71%。可以说，扩散近似在一定程度上可以应用于压水堆堆芯分析。然而，如果想要以更低的计算成本获得更准确的结果，确实需要进一步的改进。
{"title":"Evaluating the Diffusion Approximation Capability on the Integral Pressurized Water Reactor (IPWR) Core Calculation","authors":"H. Ardiansyah, M. R. Oktavian","doi":"10.17146/aij.2021.1013","DOIUrl":"https://doi.org/10.17146/aij.2021.1013","url":null,"abstract":"Diffusion approximation is an important approximation used to model a nuclear reactor core with a quite good accuracy and less computational cost. This approximation has been used widely around the globe for various kinds of nuclear reactors. This diffusion approximation is applied in a two-step method, a method combining a high fidelity transport code and low fidelity diffusion code. Meanwhile, innovations in the nuclear core model continue to make the nuclear reactor core safer, more robust, and smaller. The trend of creating smaller and more modular reactor core is emerging in the last ten years. These innovations will affect the core modeling system. Consequently, for smaller reactors, it is important to evaluate the capability of diffusion approximation if one wants to use a computationally cheaper method to model the reactor core. In this paper, neutron diffusion calculation for 160 MWth integral pressurized water reactor (IPWR) core was conducted using the PARCS nodal diffusion code employing the few-group spatially homogenized cross-sections generated by the Serpent Monte Carlo code. Due to its capability to model any reactor geometry in the high-resolution calculation, the results from Serpent were also used as a reference. Two important parameters are compared between PARCS and Serpent: effective neutron multiplication factor and core power distribution. For the full IPWR core model, a discrepancy of 564 pcm between PARCS and Serpent k eff was observed, while the radial power distribution had a maximum error of 4.71 %. It can be said, to some extent, that the diffusion approximation can be applied to IPWR core analysis. However, further improvement is indeed required if one wants more accurate results with low computational costs.","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43247017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Exposure to low-dose radiation has been demonstrated to stimulate increased cell protection when receiving subsequent challenge dose in what is known as radioadaptation response. Hsp70 and SOD, especially SOD2, are cytoprotectors against superoxide radicals generated by radiation exposure. This study aims to measure the expressions of Hsp70 and SOD2 in parotid salivary gland acinar cells as an indicator of radioadaptation response stimulated by low-dose gamma irradiation. The study used 24 male Rattus norvegicus that are divided into four groups: normal control, positive control, with 50-mGy priming irradiation, and with 100-mGy priming irradiation. The animals were immobilized without anesthetics with special tools designed especially for this study. Irradiation was carried out using a cobalt-60 (gamma ray) teletherapy unit (Philips XK-100) directed to the dorsa of the animals’ heads . High-dose gamma irradiation (2 Gy) was administered 5 hours after priming irradiation. The expression of Hsp70 and SOD2 was measured through immunohistochemical technique on the parotid salivary gland acinar cells and observed using a light microscope with 1000× magnification. Data obtained was analyzed with one-way ANOVA test ( α = 0.05). The results showed that Hsp70 and SOD2 expressions in the priming irradiation groups were higher than those in control groups. The conclusion of this study: priming irradiation with low-dose gamma radiation before challenge irradiation with high-dose gamma radiation increases the radioadaptation response of salivary gland acinar cells through induction of Hsp70 and SOD2.
{"title":"Priming Low-Dose Gamma Irradiation Increases Cellular Radioadaptation Response through the Induction of Hsp70 and SOD2","authors":"S. Supriyadi","doi":"10.17146/aij.2021.1019","DOIUrl":"https://doi.org/10.17146/aij.2021.1019","url":null,"abstract":"Exposure to low-dose radiation has been demonstrated to stimulate increased cell protection when receiving subsequent challenge dose in what is known as radioadaptation response. Hsp70 and SOD, especially SOD2, are cytoprotectors against superoxide radicals generated by radiation exposure. This study aims to measure the expressions of Hsp70 and SOD2 in parotid salivary gland acinar cells as an indicator of radioadaptation response stimulated by low-dose gamma irradiation. The study used 24 male Rattus norvegicus that are divided into four groups: normal control, positive control, with 50-mGy priming irradiation, and with 100-mGy priming irradiation. The animals were immobilized without anesthetics with special tools designed especially for this study. Irradiation was carried out using a cobalt-60 (gamma ray) teletherapy unit (Philips XK-100) directed to the dorsa of the animals’ heads . High-dose gamma irradiation (2 Gy) was administered 5 hours after priming irradiation. The expression of Hsp70 and SOD2 was measured through immunohistochemical technique on the parotid salivary gland acinar cells and observed using a light microscope with 1000× magnification. Data obtained was analyzed with one-way ANOVA test ( α = 0.05). The results showed that Hsp70 and SOD2 expressions in the priming irradiation groups were higher than those in control groups. The conclusion of this study: priming irradiation with low-dose gamma radiation before challenge irradiation with high-dose gamma radiation increases the radioadaptation response of salivary gland acinar cells through induction of Hsp70 and SOD2.","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46654365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Priyanto, M. Muslih, A. Insani, B. Bharoto, A. Ramadhani, H. Mugirahardjo
Duplex stainless steel (DSS) is a type of stainless steel that’s used in the medical and industrial such as petrochemical, oil and gas, and pharmaceutical because it has an excellent corrosion resistance and high strength. Some characterization has been carried out to know the characteristic of DSS. Characterization using neutron diffraction method by means of BATAN’s texture diffractometer DN2 was performed on a DSS series 2205 sample. From crystal structure and phase analysis, the sample has dual phases,ferrite α-phase BCC and austenite -phase FCC as it is well known. It is found that lattice parameters of ferrite and austenite are 2.8736 A and 3.6076 A, respectively. Preferred orientation (G1) for ferrite and austenite are (-2.14 ± 0.03) and (0.35 ± 0.03), respectively. Pole figures refinement was calculated using triclinic to the orthorhombic sample symmetrization. From the calculation, some results are obtained. By using pole figures (110), ( 200), and (211), it is found ferrite α-phase component is oriented to {110} Goss orientation., and using the pole figures (111), (200), and (220), the austenite -phase component is oriented to {100} Cube orientation. Orientation distribution function (ODF) is calculated using Arbitrarily Defined Cells (ADC) method or direct method in the Euler angle space (1, Φ, 2). From the ODF calculation, the ferrite α-phase components, {110} Goss orientation has (ODF) = 30,737 m.r.d. The largest ODF = 32,108 m.r.d. has orientation in the basic region (110)[001] in the Euler angle space (1, Φ, 2) = (90,90,45). For the austenite -phase components {100} Cube orientation, the (ODF) = 5,149 m.r.d. is obtained. The highest ODF values, in the basic region of (010) [100] and (100) [0-10] orientation have the Euler angle space (1, Φ, 2) = (0, 90, 0) and (0, 90, 90), respectively, both have ODF = 5,224 m.r.d
{"title":"Texture Characterization of Duplex Stainless Steel 2205 Using Neutron Diffraction Method","authors":"T. Priyanto, M. Muslih, A. Insani, B. Bharoto, A. Ramadhani, H. Mugirahardjo","doi":"10.17146/aij.2020.1038","DOIUrl":"https://doi.org/10.17146/aij.2020.1038","url":null,"abstract":"Duplex stainless steel (DSS) is a type of stainless steel that’s used in the medical and industrial such as petrochemical, oil and gas, and pharmaceutical because it has an excellent corrosion resistance and high strength. Some characterization has been carried out to know the characteristic of DSS. Characterization using neutron diffraction method by means of BATAN’s texture diffractometer DN2 was performed on a DSS series 2205 sample. From crystal structure and phase analysis, the sample has dual phases,ferrite α-phase BCC and austenite -phase FCC as it is well known. It is found that lattice parameters of ferrite and austenite are 2.8736 A and 3.6076 A, respectively. Preferred orientation (G1) for ferrite and austenite are (-2.14 ± 0.03) and (0.35 ± 0.03), respectively. Pole figures refinement was calculated using triclinic to the orthorhombic sample symmetrization. From the calculation, some results are obtained. By using pole figures (110), ( 200), and (211), it is found ferrite α-phase component is oriented to {110} Goss orientation., and using the pole figures (111), (200), and (220), the austenite -phase component is oriented to {100} Cube orientation. Orientation distribution function (ODF) is calculated using Arbitrarily Defined Cells (ADC) method or direct method in the Euler angle space (1, Φ, 2). From the ODF calculation, the ferrite α-phase components, {110} Goss orientation has (ODF) = 30,737 m.r.d. The largest ODF = 32,108 m.r.d. has orientation in the basic region (110)[001] in the Euler angle space (1, Φ, 2) = (90,90,45). For the austenite -phase components {100} Cube orientation, the (ODF) = 5,149 m.r.d. is obtained. The highest ODF values, in the basic region of (010) [100] and (100) [0-10] orientation have the Euler angle space (1, Φ, 2) = (0, 90, 0) and (0, 90, 90), respectively, both have ODF = 5,224 m.r.d","PeriodicalId":8647,"journal":{"name":"Atom Indonesia","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46034198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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：