The ongoing decommissioning of the Fukushima Daiichi (1F) nuclear power plant requires the inspection of the inside of containment vessels that have been submerged in water. These inspections must locate leaks and map...The ongoing decommissioning of the Fukushima Daiichi (1F) nuclear power plant requires the inspection of the inside of containment vessels that have been submerged in water. These inspections must locate leaks and map the distribution of fuel debris in water with very low visibility. This paper reports the design and testing of an echo-PIV system that uses a single divergent signal wave and delay-and-sum processing to efficiently map the interior and fluid flow within a submerged vessel. The diverging wave and delay-and-sum processing improve upon the performance of conventional ultrasound PIV methods specifically to meet the demands of containment vessel inspections. The imaging method uses an ultrasonic linear sensor array that emits a diverging wave that covers a wide angle with a single transmission. The delay-and-sum algorithm combines echo signals recorded by each element of the sensor array. We optimized the design of an echo-PIV system in laboratory-scale tests, and then tested the prototype with a mockup of a containment vessel in a water tank. The small-scale prototype successfully located a mock leak and mapped the surface of a piece of mock debris. This prototype can be scaled up readily for inspections at the Fukushima Daiichi plant.展开更多
Children can become HIV positive (HIV+) from their mother during home birth. If the infant ingests antiretroviral (ARV), medications immediately after birth, the risk of transmission can be dramatically reduced. We ha...Children can become HIV positive (HIV+) from their mother during home birth. If the infant ingests antiretroviral (ARV), medications immediately after birth, the risk of transmission can be dramatically reduced. We have previously proposed the use of foilized, polyethylene-lined pouches to store ARV’s. Using the pouch, the mother receives the medication at an antenatal care visit, months before delivery, and if she delivers at home, tears open the pouch and drips the medication into her child’s mouth. In this work, we extend the use of the pouch to store a modern ARV, Lamivudine (3TC), often used in multi-drug regimens. Under laboratory conditions, pouches were filled with 3TC and stored at 25?C/60% relative humidity (RH) for twelve months. We found that the 3TC was stable throughout the year (maximum 5.6% of labeled concentration change). The preservatives were somewhat degraded by the act of repackaging the medicine, but sufficient preservatives remained to maintain the medication. The same impurities were identified in the 3TC stored in the pouches and the samples removed from the bottles indicating that the pouches do not introduce new impurities (impurities that are not already introduced by the bottle). We conclude that the pouch can preserve this modern ARV for up to twelve months.展开更多
文摘The ongoing decommissioning of the Fukushima Daiichi (1F) nuclear power plant requires the inspection of the inside of containment vessels that have been submerged in water. These inspections must locate leaks and map the distribution of fuel debris in water with very low visibility. This paper reports the design and testing of an echo-PIV system that uses a single divergent signal wave and delay-and-sum processing to efficiently map the interior and fluid flow within a submerged vessel. The diverging wave and delay-and-sum processing improve upon the performance of conventional ultrasound PIV methods specifically to meet the demands of containment vessel inspections. The imaging method uses an ultrasonic linear sensor array that emits a diverging wave that covers a wide angle with a single transmission. The delay-and-sum algorithm combines echo signals recorded by each element of the sensor array. We optimized the design of an echo-PIV system in laboratory-scale tests, and then tested the prototype with a mockup of a containment vessel in a water tank. The small-scale prototype successfully located a mock leak and mapped the surface of a piece of mock debris. This prototype can be scaled up readily for inspections at the Fukushima Daiichi plant.
文摘Children can become HIV positive (HIV+) from their mother during home birth. If the infant ingests antiretroviral (ARV), medications immediately after birth, the risk of transmission can be dramatically reduced. We have previously proposed the use of foilized, polyethylene-lined pouches to store ARV’s. Using the pouch, the mother receives the medication at an antenatal care visit, months before delivery, and if she delivers at home, tears open the pouch and drips the medication into her child’s mouth. In this work, we extend the use of the pouch to store a modern ARV, Lamivudine (3TC), often used in multi-drug regimens. Under laboratory conditions, pouches were filled with 3TC and stored at 25?C/60% relative humidity (RH) for twelve months. We found that the 3TC was stable throughout the year (maximum 5.6% of labeled concentration change). The preservatives were somewhat degraded by the act of repackaging the medicine, but sufficient preservatives remained to maintain the medication. The same impurities were identified in the 3TC stored in the pouches and the samples removed from the bottles indicating that the pouches do not introduce new impurities (impurities that are not already introduced by the bottle). We conclude that the pouch can preserve this modern ARV for up to twelve months.
