The Southwestern Sumatran Waters of the Eastern Indian Ocean are known to be affected by the South Java Current and the South Equatorial Counter Current. Many studies have been carried out in relation to upwelling and the Indonesian Through Flow. However, there has been no systematic study into the properties of the particulate organic matter in the Southwestern Sumatran Waters. Therefore, the organic matter in these waters in terms of its origin is unknown. As part of the Widya Nusantara Expedition 2015 research cruise, this study aimed to examine the stable isotope ?13C signature of particulate organic matter (POM), especially with regards to the origins of the organic matter. The stable isotope ?13C is complemented by other variables such as chlorophyll-a, particulate organic carbon (POC), and nutrients (phosphate, silicate, ammonium and nitrate). The POC tends to be depth-dependent. The values of ?13C are ?23.56, ?24.30 and ?24.06‰ for 5, 100 and 300 m depths, respectively. We found that POM tended to be isotopically lighter with increasing POC and chl-a, especially in the surface water, potentially due to the preferential lighter carbon isotope for metabolism by the primary producer. The origin of POM in the Southwestern Sumatran waters is marine end-member in the surface (up to 100 m depth) and mixed compositions at the surface of twilight zone (100–300 m depth). The next layer, i.e. twilight zone (more than 300 m depth), is terrigenous end-member. The surface POM of SSW, as shown in 5 m depth, is not freshly produced and tends to be either autochthonous or allochthonous.
{"title":"Stable Carbon Isotope Signature of Particulate Organic Matter in the Southwestern Sumatran Waters of the Eastern Indian Ocean","authors":"A. J. Wahyudi, A. Afdal, H. Meirinawati","doi":"10.29037/AJSTD.555","DOIUrl":"https://doi.org/10.29037/AJSTD.555","url":null,"abstract":"The Southwestern Sumatran Waters of the Eastern Indian Ocean are known to be affected by the South Java Current and the South Equatorial Counter Current. Many studies have been carried out in relation to upwelling and the Indonesian Through Flow. However, there has been no systematic study into the properties of the particulate organic matter in the Southwestern Sumatran Waters. Therefore, the organic matter in these waters in terms of its origin is unknown. As part of the Widya Nusantara Expedition 2015 research cruise, this study aimed to examine the stable isotope ?13C signature of particulate organic matter (POM), especially with regards to the origins of the organic matter. The stable isotope ?13C is complemented by other variables such as chlorophyll-a, particulate organic carbon (POC), and nutrients (phosphate, silicate, ammonium and nitrate). The POC tends to be depth-dependent. The values of ?13C are ?23.56, ?24.30 and ?24.06‰ for 5, 100 and 300 m depths, respectively. We found that POM tended to be isotopically lighter with increasing POC and chl-a, especially in the surface water, potentially due to the preferential lighter carbon isotope for metabolism by the primary producer. The origin of POM in the Southwestern Sumatran waters is marine end-member in the surface (up to 100 m depth) and mixed compositions at the surface of twilight zone (100–300 m depth). The next layer, i.e. twilight zone (more than 300 m depth), is terrigenous end-member. The surface POM of SSW, as shown in 5 m depth, is not freshly produced and tends to be either autochthonous or allochthonous.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49310295","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}
This paper discusses the spatial trends of urban physical growth of several cities in Java. Six cities in Java (Jakarta, Bandung, Semarang, Yogyakarta, Surabaya, and Malang) were chosen as samples to represent the characteristics of cities in Java based on their geographic settings, including their topography, size, population density, and history of their development. The objectives of this study were: (1) to understand the variations in physical growth of cities in Java; and (2) to explain the spatial trends of urban physical growth of these cities based on their geographic settings. Multi-temporal Landsat satellite images were chosen as data sources to identify urban morphological development processes. Based on results of analysis, it was found that the physical growth of cities in Java has had relatively diverse variations in the aspects of urban settlements, infrastructure, and urban functions. However, the diversity of urban physical growth can be simplified into four types based on the dominant form of physical development. These four types were found to be (1) a compact-rounded city that is formed by the domination of a densification process; (2) a spread-elongated city formed by the dominance of an extensification process; (3) a compact fan-shaped city that is formed by natural physical conditions; and (4) a scattered-random city formed by the domination of a leapfrogging process.
{"title":"Spatial Trends of Urban Physical Growth of Cities in Java, Indonesia, 1975–2015","authors":"D. Marwasta","doi":"10.29037/AJSTD.579","DOIUrl":"https://doi.org/10.29037/AJSTD.579","url":null,"abstract":"This paper discusses the spatial trends of urban physical growth of several cities in Java. Six cities in Java (Jakarta, Bandung, Semarang, Yogyakarta, Surabaya, and Malang) were chosen as samples to represent the characteristics of cities in Java based on their geographic settings, including their topography, size, population density, and history of their development. The objectives of this study were: (1) to understand the variations in physical growth of cities in Java; and (2) to explain the spatial trends of urban physical growth of these cities based on their geographic settings. Multi-temporal Landsat satellite images were chosen as data sources to identify urban morphological development processes. Based on results of analysis, it was found that the physical growth of cities in Java has had relatively diverse variations in the aspects of urban settlements, infrastructure, and urban functions. However, the diversity of urban physical growth can be simplified into four types based on the dominant form of physical development. These four types were found to be (1) a compact-rounded city that is formed by the domination of a densification process; (2) a spread-elongated city formed by the dominance of an extensification process; (3) a compact fan-shaped city that is formed by natural physical conditions; and (4) a scattered-random city formed by the domination of a leapfrogging process.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44528267","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. Rahmawati, Lutfi Ardianti, Salma Hayyu Nur Husna, Eni Paryani, Nur Amrina Rosidhah, T. Amalia, R. F. Putri
This study aimed to explain the conditions of poverty in Gorontalo Province, Sulawesi, Indonesia, to identify the causes of poverty in the province, and then to propose efforts to reduce this poverty. Data related to human and economic resources were used in the analysis. The condition of poverty was seen through the DPSIR approach, which consists of the driver (D), pressure (P), state (S), impact (I), and response (R). Poverty in Gorontalo Province could be reduced by utilizing the occupation that dominates the population, which is in agriculture sector. Therefore, developing an agropolitan system is a solution. In the first stage, the location quotient (LQ), shift share (SS), and Klassen typology methods were used to determine regencies or cities that have the potential to develop an agropolitan system. The results of the analysis showed that there were two districts that have the potential to develop agropolitan systems, namely Pohuwato Regency and Gorontalo Regency. Efforts to reduce poverty in Gorontalo Province with an agropolitan system can be continued with a second stage consisting of the preparation of products and forms of management organizations, and a third stage in the form of strengthening human resources.
{"title":"Poverty Approach and How to Reduce it with an Agropolitan Program in Gorontalo Province, Indonesia","authors":"A. Rahmawati, Lutfi Ardianti, Salma Hayyu Nur Husna, Eni Paryani, Nur Amrina Rosidhah, T. Amalia, R. F. Putri","doi":"10.29037/AJSTD.578","DOIUrl":"https://doi.org/10.29037/AJSTD.578","url":null,"abstract":"This study aimed to explain the conditions of poverty in Gorontalo Province, Sulawesi, Indonesia, to identify the causes of poverty in the province, and then to propose efforts to reduce this poverty. Data related to human and economic resources were used in the analysis. The condition of poverty was seen through the DPSIR approach, which consists of the driver (D), pressure (P), state (S), impact (I), and response (R). Poverty in Gorontalo Province could be reduced by utilizing the occupation that dominates the population, which is in agriculture sector. Therefore, developing an agropolitan system is a solution. In the first stage, the location quotient (LQ), shift share (SS), and Klassen typology methods were used to determine regencies or cities that have the potential to develop an agropolitan system. The results of the analysis showed that there were two districts that have the potential to develop agropolitan systems, namely Pohuwato Regency and Gorontalo Regency. Efforts to reduce poverty in Gorontalo Province with an agropolitan system can be continued with a second stage consisting of the preparation of products and forms of management organizations, and a third stage in the form of strengthening human resources.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42453140","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}
Mangrove ecosystems have multiple functions, including economic and environmental ones. For optimal benefits, mangrove ecosystem management should be well-proportioned. The purpose of this study was to determine the most appropriate scenario for managing a mangrove ecosystem alongside aquaculture ponds, by performing an economic valuation to find out the value of management with the most beneficial scenarios, both ecologically and economically. Data were collected through interviews using questionnaires, literature reviews, and institutional data. These data were then processed through economic valuations of the total economic value and cost-benefit analysis. Data were analysed spatially and descriptive-quantitatively. The total economic value of the mangrove ecosystem was USD 6.73 million. The benefit and costs of managing mangrove ecotourism were USD 3,930.74/ha/year and USD 1,701.69/ha/year, respectively, whereas the benefits and costs of managing ponds were USD 150,433.85/ha/year and USD 55,269.46/ha/year, respectively. The prioritized scenario of mangrove ecosystem management is one with an ideal proportion of mangrove and pond areas (i.e. 50:50) and the total ecological and economic benefits for a period of 25 years is USD 19.17 million.
{"title":"Developing Alternative Mangrove Ecosystem Management Scenarios through Economic Valuation in the Coastal Area of Jangkaran Village, Kulon Progo Regency, Indonesia","authors":"D. Ariestantya, R. Harini","doi":"10.29037/ajstd.575","DOIUrl":"https://doi.org/10.29037/ajstd.575","url":null,"abstract":"Mangrove ecosystems have multiple functions, including economic and environmental ones. For optimal benefits, mangrove ecosystem management should be well-proportioned. The purpose of this study was to determine the most appropriate scenario for managing a mangrove ecosystem alongside aquaculture ponds, by performing an economic valuation to find out the value of management with the most beneficial scenarios, both ecologically and economically. Data were collected through interviews using questionnaires, literature reviews, and institutional data. These data were then processed through economic valuations of the total economic value and cost-benefit analysis. Data were analysed spatially and descriptive-quantitatively. The total economic value of the mangrove ecosystem was USD 6.73 million. The benefit and costs of managing mangrove ecotourism were USD 3,930.74/ha/year and USD 1,701.69/ha/year, respectively, whereas the benefits and costs of managing ponds were USD 150,433.85/ha/year and USD 55,269.46/ha/year, respectively. The prioritized scenario of mangrove ecosystem management is one with an ideal proportion of mangrove and pond areas (i.e. 50:50) and the total ecological and economic benefits for a period of 25 years is USD 19.17 million.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45280246","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}
{"title":"X-RAY Radiography on Reflector Collimator for Boron Neutron Capture Therapy Component","authors":"Y. Sardjono, R. Adiputra, S. Budi","doi":"10.29037/AJSTD.513","DOIUrl":"https://doi.org/10.29037/AJSTD.513","url":null,"abstract":"","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49299606","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}
The oral application of probiotics in the poultry industry is time-consuming and laborious. Therefore, using a powdered probiotic supplement that can easily mix with feed is important. We investigated the effect of spray drying encapsulation on the viability of indigenous probiotic lactic acid bacteria during production and storage and evaluated broiler chicken performance after providing the supplement. Encapsulated probiotics exhibited >80% survival rates after spray drying. All bacterial species maintained up to 80% cell viability rates after exposure to 80–85°C temperatures for 15 or 30 s. The viable cell number of all encapsulated bacteria decreased over seven weeks of storage. The supplement was mixed with feed at concentrations 0.5 (T1), 1.0 (T2), and 1.5 (T3) g/kg feed and administered to 48 one-day-old Lohmann broiler chickens for 21 days; a T0 group was raised without probiotic supplementation. Probiotic supplementation affected body weight gain, live weight, and feed conversion ratio. The cecum length and duodenum and cecum weights significantly differed among the treatment groups. Probiotic supplementation was associated with improved villus development in the intestinal epithelium compared with that of the control. Thus, feed supplementation with indigenous probiotic powder stimulates intestinal epithelial proliferation in broiler chickens during the starter phase, improving their performance.
{"title":"Feed Supplementation with Encapsulated Indigenous Probiotic Lactic Acid Bacteria Increased Broiler Chicken Performance","authors":"M. S. I. Pradipta, S. Harimurti, W. Widodo","doi":"10.29037/AJSTD.569","DOIUrl":"https://doi.org/10.29037/AJSTD.569","url":null,"abstract":"The oral application of probiotics in the poultry industry is time-consuming and laborious. Therefore, using a powdered probiotic supplement that can easily mix with feed is important. We investigated the effect of spray drying encapsulation on the viability of indigenous probiotic lactic acid bacteria during production and storage and evaluated broiler chicken performance after providing the supplement. Encapsulated probiotics exhibited >80% survival rates after spray drying. All bacterial species maintained up to 80% cell viability rates after exposure to 80–85°C temperatures for 15 or 30 s. The viable cell number of all encapsulated bacteria decreased over seven weeks of storage. The supplement was mixed with feed at concentrations 0.5 (T1), 1.0 (T2), and 1.5 (T3) g/kg feed and administered to 48 one-day-old Lohmann broiler chickens for 21 days; a T0 group was raised without probiotic supplementation. Probiotic supplementation affected body weight gain, live weight, and feed conversion ratio. The cecum length and duodenum and cecum weights significantly differed among the treatment groups. Probiotic supplementation was associated with improved villus development in the intestinal epithelium compared with that of the control. Thus, feed supplementation with indigenous probiotic powder stimulates intestinal epithelial proliferation in broiler chickens during the starter phase, improving their performance.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44877328","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}
Deo Clinton Maranatha Simangunsong, Y. Sardjono, Budi Setyahandana, S. Santosa, F. Nurjaman
Boron neutron cancer therapy is a cancer treatment method that encompasses epithermal neutron irradiation of boron delivered to tumor cells. Using collimators, fast neutrons are moderated into epithermal neutrons. When radiation is performed, neutron beams are emitted and filtered by a collimator. In this study, 12 collimators used in the BNCT process were inspected for their quality, in terms of defects or flaws. The inspected collimators were manufactured by centrifugal casting and were composed of 99% pure nickel. They had the following dimensions: height of 145 mm, outer diameter of 190 mm, inner diameter of 160 mm, and thickness of 15 mm. The inspection method used was gamma radiography testing with an Iridium-192 gamma source. Using a single wall single image technique, the collimators were exposed for 30 seconds. Six FUJI films were placed behind the object to record the resulting images, which showed light or dark areas on each collimator, the latter of which indicated porosity or flaws. Based on these images, collimators 1 and 5 were found to contain cracks, and porosity was identified in almost all of the collimators. It is suggested that both collimators with cracks be recycled, while the collimators with porosities should be investigated further to determine their suitability for boron neutron cancer therapy.
{"title":"Gamma Radiography Testing of Collimators for Boron Neutron Capture Therapy","authors":"Deo Clinton Maranatha Simangunsong, Y. Sardjono, Budi Setyahandana, S. Santosa, F. Nurjaman","doi":"10.29037/AJSTD.567","DOIUrl":"https://doi.org/10.29037/AJSTD.567","url":null,"abstract":"Boron neutron cancer therapy is a cancer treatment method that encompasses epithermal neutron irradiation of boron delivered to tumor cells. Using collimators, fast neutrons are moderated into epithermal neutrons. When radiation is performed, neutron beams are emitted and filtered by a collimator. In this study, 12 collimators used in the BNCT process were inspected for their quality, in terms of defects or flaws. The inspected collimators were manufactured by centrifugal casting and were composed of 99% pure nickel. They had the following dimensions: height of 145 mm, outer diameter of 190 mm, inner diameter of 160 mm, and thickness of 15 mm. The inspection method used was gamma radiography testing with an Iridium-192 gamma source. Using a single wall single image technique, the collimators were exposed for 30 seconds. Six FUJI films were placed behind the object to record the resulting images, which showed light or dark areas on each collimator, the latter of which indicated porosity or flaws. Based on these images, collimators 1 and 5 were found to contain cracks, and porosity was identified in almost all of the collimators. It is suggested that both collimators with cracks be recycled, while the collimators with porosities should be investigated further to determine their suitability for boron neutron cancer therapy.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43424012","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}
Cocopeat, a by-product of coconut husk, was used as adsorbent material to remove mercury (Hg) and other heavy metals (As, Ba, Cd, Pb) from the wastewater gathered from the tailings collection tank of a ball mill facility at the small scale gold mining (SSGM) area in Camarines Norte province, Philippines. Batch sorption tests were carried out using actual wastewater samples with reduced suspended solids collected after 60 min of settling and without modifying the pH and other parameters to simulate the actual condition in the field. Batch tests of water samples with an initial pH of 7.30 and adsorbent dose of 1.0 g cocopeat/L were tested for Lagergren first-order, pseudo-second-order, intra-particle diffusion, and Freundlich models to evaluate kinetic parameters and adsorption isotherms. The removal efficiencies obtained for the heavy metals after the equilibrium time of 240 min were 97.14%, 94.74%, 10.00%, 66.67%, and 27.01% for Hg, As, Ba, Cd, and Pb, respectively. The pseudo-second order kinetics model represented well the adsorption process as demonstrated with its higher correlation coefficients among the models.
{"title":"Removal of Heavy Metals from an Actual Small Scale Gold Mining Wastewater by Sorption onto Cocopeat","authors":"J. Samaniego, M. Tanchuling","doi":"10.29037/AJSTD.558","DOIUrl":"https://doi.org/10.29037/AJSTD.558","url":null,"abstract":"Cocopeat, a by-product of coconut husk, was used as adsorbent material to remove mercury (Hg) and other heavy metals (As, Ba, Cd, Pb) from the wastewater gathered from the tailings collection tank of a ball mill facility at the small scale gold mining (SSGM) area in Camarines Norte province, Philippines. Batch sorption tests were carried out using actual wastewater samples with reduced suspended solids collected after 60 min of settling and without modifying the pH and other parameters to simulate the actual condition in the field. Batch tests of water samples with an initial pH of 7.30 and adsorbent dose of 1.0 g cocopeat/L were tested for Lagergren first-order, pseudo-second-order, intra-particle diffusion, and Freundlich models to evaluate kinetic parameters and adsorption isotherms. The removal efficiencies obtained for the heavy metals after the equilibrium time of 240 min were 97.14%, 94.74%, 10.00%, 66.67%, and 27.01% for Hg, As, Ba, Cd, and Pb, respectively. The pseudo-second order kinetics model represented well the adsorption process as demonstrated with its higher correlation coefficients among the models.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46893079","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}
In this study, Rockwell and Brinell hardness testing was used to examine material hardness. These methods were chosen because they are easy to carry out, relatively inexpensive, and almost all sizes and shapes can be tested, in which nickel hardness before and after centrifugal casting are identified and compared. These tests enable the determination of the hardness numbers of nickel collimators using for boron neutron capture therapy. The samples were five nickel plates with a dimension of 4.5 × 4.5 cm and five collimators. The collimators were cylindrical and made using centrifugal casting. The basic principle of the hardness test was to apply loading on the object being tested. The Rockwell test was used to assess the material's hardness from the difference of indentation depth, while the Brinell test was used to determine the hardness from the diameter of indentation. From the results of this test, the hardness number of nickel before centrifugal casting is 168.53 BHN or 86.13 HRB, while the hardness number after centrifugal casting is 115.68 BHN or 64.84 HRB. It can therefore be concluded that centrifugal casting decreased nickel hardness.
{"title":"Rockwell Hardness Testing of Pure Nickel Collimators for BNCT Application","authors":"Erasmus Prakasita, Y. Sardjono, Budi Setyahandana","doi":"10.29037/AJSTD.525","DOIUrl":"https://doi.org/10.29037/AJSTD.525","url":null,"abstract":"In this study, Rockwell and Brinell hardness testing was used to examine material hardness. These methods were chosen because they are easy to carry out, relatively inexpensive, and almost all sizes and shapes can be tested, in which nickel hardness before and after centrifugal casting are identified and compared. These tests enable the determination of the hardness numbers of nickel collimators using for boron neutron capture therapy. The samples were five nickel plates with a dimension of 4.5 × 4.5 cm and five collimators. The collimators were cylindrical and made using centrifugal casting. The basic principle of the hardness test was to apply loading on the object being tested. The Rockwell test was used to assess the material's hardness from the difference of indentation depth, while the Brinell test was used to determine the hardness from the diameter of indentation. From the results of this test, the hardness number of nickel before centrifugal casting is 168.53 BHN or 86.13 HRB, while the hardness number after centrifugal casting is 115.68 BHN or 64.84 HRB. It can therefore be concluded that centrifugal casting decreased nickel hardness.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48096010","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. Murtafi'atin, W. Widarto, S. Susilo, N. M. D. Putra
This research aimed to determine the potential of barite concrete as a neutron radiation shielding material in the development of boron neutron capture therapy, by obtaining its neutron attenuation coefficient. Barite concrete samples were supplied by the Center of Accelerator Science and Technology in Yogyakarta, Indonesia. The experiment consisted of two parts, namely density analysis and determination of the neutron attenuation coefficient. For the latter, plutonium-beryllium was used as the neutron source, while a high purity germanium detector was used to measure the neutron radiation level. The results showed that barite concrete with a 2130 kg.m–3 density had a neutron attenuation coefficient of 0.0871 cm–3.
{"title":"Analysis of Barite Concrete as a Potential Neutron Radiation Shielding Material for BNCT Facilities","authors":"R. Murtafi'atin, W. Widarto, S. Susilo, N. M. D. Putra","doi":"10.29037/AJSTD.528","DOIUrl":"https://doi.org/10.29037/AJSTD.528","url":null,"abstract":"This research aimed to determine the potential of barite concrete as a neutron radiation shielding material in the development of boron neutron capture therapy, by obtaining its neutron attenuation coefficient. Barite concrete samples were supplied by the Center of Accelerator Science and Technology in Yogyakarta, Indonesia. The experiment consisted of two parts, namely density analysis and determination of the neutron attenuation coefficient. For the latter, plutonium-beryllium was used as the neutron source, while a high purity germanium detector was used to measure the neutron radiation level. The results showed that barite concrete with a 2130 kg.m–3 density had a neutron attenuation coefficient of 0.0871 cm–3.","PeriodicalId":8479,"journal":{"name":"Asean Journal on Science and Technology for Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42934467","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}
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