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Ahmad Mushtaq - One of the best experts on this subject based on the ideXlab platform.
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Conversion of Molybdenum-99 production process to low enriched uranium: Neutronic and thermal hydraulic analyses of HEU and LEU target plates for irradiation in Pakistan Research Reactor-1
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2012Co-Authors: Ahmad Mushtaq, Masood Iqbal, Ishtiaq Hussain Bokhari, Tayyab Mahmood, Atta MuhammadAbstract:Abstract Technetium-99m, the daughter product of Molybdenum-99 is the most widely needed radionuclide for diagnostic studies in Pakistan. Molybdenum-99 Production Facility has been established at PINSTECH. Highly enriched uranium (93% 235 U) U/Al alloy targets have been irradiated in Pakistan Research Reactor-1 (PARR-1) for the generation of fission Mo-99, while basic dissolution technique is used for separation of Mo-99 from target matrix activity. In line with the international objective of minimizing and eventually eliminating the use of HEU in civil commerce, national and international efforts have been underway to shift the production of medical isotopes from HEU to LEU (LEU; 235 U enrichment) targets. To achieve the equivalent amount of 99 Mo with LEU targets, approximately 5 times uranium is needed. LEU aluminum uranium dispersion target has been developed, which may replace existing HEU aluminum/uranium alloy targets for production of 99 Mo using basic dissolution technique. Neutronic and thermal hydraulic calculations were performed for safe irradiation of targets in the core of PARR-1.
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Disposition of plutonium-239 via production of fission Molybdenum-99.
Applied radiation and isotopes : including data instrumentation and methods for use in agriculture industry and medicine, 2011Co-Authors: Ahmad MushtaqAbstract:Abstract A heritage of physical consequences of the U.S.–Soviet arms race has accumulated, the weapons-grade plutonium (WPu), which will become excess as a result of the dismantlement of the nuclear weapons under the arms reduction agreements. Disposition of Pu has been proposed by mixing WPu with high-level radioactive waste with subsequent vitrification into large, highly radioactive glass logs or fabrication into mixed oxide fuel with subsequent irradiation in existing light water reactors. A potential option may be the production of medical isotope Molybdenum-99 by using Pu-239 targets.
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Specifications and qualification of uranium/aluminum alloy plate target for the production of fission Molybdenum-99
Nuclear Engineering and Design, 2011Co-Authors: Ahmad MushtaqAbstract:In all probability, the same criteria applied to evaluate the safety of the reactor fuel shall be used to evaluate the safety of the targets used for the production of fission Molybdenum-99. Thus, neutronic and thermal hydraulics considerations will dictate the maximum power of the targets, their uranium content, and the uniformity requirements for their loading. Radiography technique is capable of characterizing both meat location and density. Specifically, target plates that meet fuel density specifications can be irradiated with little risk of power peaking and hot spots. An adequate characterization and qualification of target plate cladding is also critical, because cladding breaches will contaminate the reactor coolant. Bend testing is a dependable way of testing bond strength while Ultrasonic Testing (UT) examinations qualify both bonding homogeneity and minimum thickness of that cladding. The bonding quality is inspected by means of a blister test. Lastly, optical microscopy is applied for clad thickness, which further supports the veracity of the UT characterization method. Natural U/Al alloy plate targets have been safely irradiated in the core of Pakistan Research Reactor-1.
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low enriched uranium foil plate target for the production of fission Molybdenum 99 in pakistan research reactor 1
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2009Co-Authors: Ahmad Mushtaq, Masood Iqbal, Ishtiaq Hussain Bokhari, Tayyab MahmoodAbstract:Low enriched uranium foil (19.99% 235U) will be used as target material for the production of fission Molybdenum-99 in Pakistan Research Reactor-1 (PARR-1). LEU foil plate target proposed by University of Missouri Research Reactor (MURR) will be irradiated in PARR-1 for the production of 100Ci of Molybdenum-99 at the end of irradiation, which will be sufficient to prepare required 99Mo/99mTc generators at Pakistan Institute of Nuclear Science and Technology, Islamabad (PINSTECH) and its supply in the country. Neutronic and thermal hydraulic analysis for the fission Molybdenum-99 production at PARR-1 has been performed. Power levels in target foil plates and their corresponding irradiation time durations were initially determined by neutronic analysis to have the required neutron fluence. Finally, the thermal hydraulic analysis has been carried out for the proposed design of the target holder using LEU foil plates for fission Molybdenum-99 production at PARR-1. Data shows that LEU foil plate targets can be safely irradiated in PARR-1 for production of desired amount of fission Molybdenum-99.
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Neutronic and thermal hydraulic analysis for production of fission Molybdenum-99 at Pakistan Research Reactor-1
Annals of Nuclear Energy, 2008Co-Authors: Ahmad Mushtaq, Massod Iqbal, Ishtiaq Hussain Bokhari, Tariq Mahmood, Tayyab Mahmood, Zahoor Ahmad, Qamar ZamanAbstract:Abstract Neutronic and thermal hydraulic analysis for the fission Molybdenum-99 production at PARR-1 has been performed. Low enriched uranium foil ( 235 U) will be used as target material. Annular target designed by ANL (USA) will be irradiated in PARR-1 for the production of 100 Ci of Molybdenum-99 at the end of irradiation, which will be sufficient to prepare required 99 Mo/ 99m Tc generators at PINSTECH and its supply in the country. Neutronic and thermal hydraulic analysis were performed using various codes. Data shows that annular targets can be safely irradiated in PARR-1 for production of required amount of fission Molybdenum-99.
Ann Voslar - One of the best experts on this subject based on the ideXlab platform.
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Effects of technetium-99m/Molybdenum-99 shortage on Wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine
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effects of technetium 99m Molybdenum 99 shortage on wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine
Charlie W. Allen - One of the best experts on this subject based on the ideXlab platform.
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Thermal-Mechanical Response of Non-Uniformly Heated Nominally Flat and Curved LEU Foil Based Target
Volume 7: Fluids and Heat Transfer Parts A B C and D, 2012Co-Authors: Kyler K. Turner, Gary L. Solbrekken, Charlie W. AllenAbstract:Technetium-99m is a radiopharmaceutical currently used in 85% of all diagnostic imaging procedures. The relative long lived parent isotope of technetium-99m is Molybdenum-99, which is commonly produced by irradiating highly enriched uranium. In accordance with the Department of Energy: National Nuclear Security Administration’s Global Threat Reduction Initiative an effort is underway to develop low enriched uranium based Molybdenum-99 production concepts. Achieving comparable Molybdenum-99 yields in a low enriched uranium target effectively mandates the use of a high density metal low enriched uranium foil. Using a foil requires a significant modification to the current highly enriched uranium dispersion target designs. One design concept uses a low enriched uranium foil sandwiched between either two flat or curved aluminum plates. The low enriched uranium is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by low enriched uranium fuel plates with the exception that the low enriched uranium is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. The lack of bonding between the low enriched uranium foil and the plates allows easy removal of the foil after irradiation for chemically processing and separation. The un-heated edges of the plate target produce three-dimensional temperature gradients inducing deformations and stress. This paper will review the thermal mechanical response of a low enriched uranium foil based Molybdenum-99 production target. This study describes the effect of various curvatures, thermal loads, and heat transfer coefficients on the thermal-induced deflection and stress.Copyright © 2012 by ASME
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Thermal-Mechanical Response of Non-Uniformly Heated LEU Foil Based Target
Volume 10: Heat and Mass Transport Processes Parts A and B, 2011Co-Authors: Kyler K. Turner, Gary L. Solbrekken, Charlie W. AllenAbstract:Technetium-99m is a diagnostic radiopharmaceutical that is currently used in 80% of the global nuclear diagnostic imaging procedures. The parent isotope for technetium-99m is Molybdenum-99, most commonly obtained through the irradiation of high enriched uranium (HEU) targets. In accordance with the Department of Energy’s Global Threat Reduction Initiative (GTRI) an effort is underway to develop a process to produce Molybdenum-99 using low enriched uranium (LEU) targets to maintain production yield relative to HEU targets. Conversion of targets to LEU material effectively mandates that the most efficient process is to cast LEU in the form of a metal foil as opposed to current powder based dispersion designs for HEU. Using a foil requires a significant modification to the current target design. One design concept uses an LEU foil sandwiched between two nominally flat aluminum plates. The LEU is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by high density monolithic LEU fuel plates with the exception that the LEU is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. The lack of bonding between the LEU foil and the plates allows the edges of the plate to be cut off so the foil can be removed after irradiation to be chemically processed. The un-heated edges of the plate target produce 3-D temperature gradients that induce plate deformations. This paper will review thermal mechanical response of an LEU foil based Molybdenum-99 plate target geometry. This study describes the effect of various edge holding conditions, thermal loads, and heat transfer coefficients on the thermal-induced deflection and stress in the plates.Copyright © 2011 by ASME
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Thermal-Mechanical Analysis of Varying Boundary Conditions on a LEU Foil Based Molybdenum-99 Plate Processing Target
Volume 9: Mechanics of Solids Structures and Fluids, 2010Co-Authors: Kyler K. Turner, Gary L. Solbrekken, Charlie W. AllenAbstract:Technetium-99m is a diagnostic radio-pharmaceutical that is currently used in 85% of the United States diagnostic imaging procedures [1]. All supplies of technetium-99m’s parent isotope Molybdenum-99 currently originate from the irradiation of high enriched uranium (HEU) in nuclear reactor facilities located outside the United States. In accordance with the Global Threat Reduction Initiative all uranium used in future Molybdenum-99 production will use low enriched uranium (LEU). Conversion to LEU material effectively mandates using LEU in the form of a metal foil as opposed to current powder based dispersion designs for HEU. Using a foil requires a significant modification to the current target design. One design approach uses an LEU foil sandwiched between two nominally flat aluminum plates. The LEU is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by LEU fuel plates with the exception that the LEU is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. This paper will review the thermal-mechanical analysis of an LEU based Molybdenum-99 target with plate geometry. This study describes the impact of boundary conditions on the thermally-induced stress and strain in the aluminum plates.© 2010 ASME
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thermal mechanical analysis of annular target design for high volume production of Molybdenum 99 using low enriched uranium
ASME 2009 International Mechanical Engineering Congress and Exposition, 2009Co-Authors: Kyler K. Turner, Gary L. Solbrekken, Charlie W. AllenAbstract:Techenetium-99m is a diagnostic radioactive medical isotope that is currently used 30,000 times a day in the United States. All supplies of techenetium-99m’s parent isotope Molybdenum-99 currently originate from nuclear reactor facilities located in foreign countries and use highly enriched uranium (HEU). In accordance with the Global Threat Reduction Initiative all uranium used in future Molybdenum-99 production will use low enriched uranium (LEU). A design approach to using LEU in a cost-effective manner is to use a target that is based on LEU foil. A potential failure mode for the LEU foil based target is temperature excursion during irradiation due to poor thermal contact between the foil and the target cladding. The purpose of this study is to establish the theoretical basis for experimentally measuring the thermal contact resistance. Replicating in service heating conditions is nearly impossible when testing the thermal contact resistance as part of a study to establish LEU foil warpage tolerances, thus it is necessary to establish an alternate heating configuration that will allow a conservative estimate of the contact resistance. Thermal and mechanical analysis suggests that external heating of an annular target will place the interface into a state that will over-estimate the contact resistance relative to use conditions. Further, the magnitude of the heat load used for testing can be adjusted to control the degree of overestimation.
Stacy Sengpiel - One of the best experts on this subject based on the ideXlab platform.
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Effects of technetium-99m/Molybdenum-99 shortage on Wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine
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effects of technetium 99m Molybdenum 99 shortage on wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine
Amanda Keller - One of the best experts on this subject based on the ideXlab platform.
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Effects of technetium-99m/Molybdenum-99 shortage on Wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine
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effects of technetium 99m Molybdenum 99 shortage on wisconsin nuclear medicine departments
The Journal of Nuclear Medicine, 2010Co-Authors: Stacy Sengpiel, Amanda Keller, Ann VoslarAbstract:2110 Objectives The Chalk River Reactor shutdown has greatly reduced the amount of Tc-99m/Mo-99 available for nuclear medicine patient procedures. The severity of this problem was investigated. Methods All in-house Nuclear Medicine departments in Wisconsin were asked a series of questions to determine how the recent Chalk River Reactor shutdown has impacted their services. Hospitals were divided into two categories: small ( 150 staffed beds) to determine if size of the institution was a factor. Results Analyzed data included 34 small and 31 large hospitals. Both categories experienced difficulties in obtaining adequate amounts of Tc-99m essential in providing patients with the best quality of care. Hospitals of all sizes were forced to come up with solutions to rectify the shortage. Solutions included: 1) ordering unit doses rather than a generator 2) rescheduling patient procedures, and 3) using Tl-201 in place of Tc-99m. In some cases, patients were imaged using a different modality such as a spiral CT or stress echo. (Figure 1 attached). Conclusions In order for nuclear medicine to continue to be a valued and utilized department in the healthcare field it is necessary to discover a solution to the Tc-99m/Mo-99m shortage. While Tl-201 is a suitable replacement for nuclear cardiology studies, it increases patient radiation exposure and imaging time. It is more cost effective for large nuclear medicine departments to use Molybdenum-99 generators and that product also allows the department to have more flexibilty on their patient schedule. Rescheduling procedures, even by as little as one day, can be detrimental to patient health and certainly delays care and drives up health care costs. Approximately 21% of hospitals reported having diverted at least one patient to a different modality. This may be the most concerning statistic for the future of nuclear medicine. It is important that a new source of Tc-99m be found before physicians begin relying on other modalities more heavily for services previously performed in nuclear medicine