This study aims to investigate the responses of a perovskite-based direct-conversion dual-layer flat-panel detector(DL-FPD)numerically.To this end,the X-ray sensitivity,spatial resolution quantified by the modulation ...This study aims to investigate the responses of a perovskite-based direct-conversion dual-layer flat-panel detector(DL-FPD)numerically.To this end,the X-ray sensitivity,spatial resolution quantified by the modulation transfer function(MTF),and detective quantum efficiency(DQE)of the DL-FPD are evaluated numerically using a linear cascade model.In addition,both the single-crystal(SC)and polycrystalline(PC)structures of MAPbI_(3)are investigated,along with various other key parameters such as the material thickness,electric field strength,X-ray beam spectrum,and electronic readout noise.The results demonstrate that SC perovskite consistently exhibits better performance than PC perovskite owing to fewer material defects.Increasing the layer thickness may decrease the MTF,but can also enhance the sensitivity and DQE.Moreover,appropriately increasing the external electric field within the material can improve the sensitivity,MTF,and DQE.Finally,reducing the electronic readout noise can significantly enhance the DQE for low-dose imaging.This study demonstrates the potential of high-quality dual-energy X-ray imaging using direct-conversion perovskite DL-FPDs.展开更多
There is an increasing demand for salmonid authentication due to the globalization of the salmonid trade.DNA barcoding and mini-DNA barcoding are widely used for identifying fish species based on a fragment of the mit...There is an increasing demand for salmonid authentication due to the globalization of the salmonid trade.DNA barcoding and mini-DNA barcoding are widely used for identifying fish species based on a fragment of the mitochondrial cytochrome c oxidase subunit I(COI)sequence.In this study,rainbow trout(Oncorhynchus mykiss),steelhead trout(O.mykiss),and Atlantic salmon(Salmo salar)collected from two salmonid aquaculture bases in China were authenticated by DNA barcoding(about 650 bp)and mini-DNA barcoding(127 bp)to evaluate the accuracy of the two methods in the identification of different salmonid species.The results revealed that both methods could effectively distinguish O.mykiss and S.salar with 100%accuracy.However,the two methods failed to separate rainbow trout(O.mykiss)and steelhead trout(O.mykiss),which are the same species but cultured in different water environments.Moreover,salmonid samples from three main distribution channels in the Qingdao area(traditional supermarkets,online supermarkets,and sushi bars)were identified by the two methods.Substitution of S.salar with O.mykiss was discovered,and the 27.78%overall substitution rate of salmonids in the Qingdao area was higher than those in other regions reported in previous studies.In addition,the mislabeling rates of salmonids from traditional supermarkets,online supermarkets,and sushi bars were compared in this study.The mislabeling rate was significantly greater in sushi bars(50%)than in the other two channels(16.67%),suggesting that stronger monitoring and enforcement measures are necessary for the aquatic food catering industry.展开更多
基金supported in part by the National Natural Science Foundation of China(Nos.12305349,12235006,12027812)Shenzhen Science and Technology Program(No.JSGGKQTD20210831174329010)Guangdong Basic and Applied Basic Research Foundation(No.2021TQ06Y108).
文摘This study aims to investigate the responses of a perovskite-based direct-conversion dual-layer flat-panel detector(DL-FPD)numerically.To this end,the X-ray sensitivity,spatial resolution quantified by the modulation transfer function(MTF),and detective quantum efficiency(DQE)of the DL-FPD are evaluated numerically using a linear cascade model.In addition,both the single-crystal(SC)and polycrystalline(PC)structures of MAPbI_(3)are investigated,along with various other key parameters such as the material thickness,electric field strength,X-ray beam spectrum,and electronic readout noise.The results demonstrate that SC perovskite consistently exhibits better performance than PC perovskite owing to fewer material defects.Increasing the layer thickness may decrease the MTF,but can also enhance the sensitivity and DQE.Moreover,appropriately increasing the external electric field within the material can improve the sensitivity,MTF,and DQE.Finally,reducing the electronic readout noise can significantly enhance the DQE for low-dose imaging.This study demonstrates the potential of high-quality dual-energy X-ray imaging using direct-conversion perovskite DL-FPDs.
基金the National Key Research and Development Program of China(No.2019YFD0901000)the Natural Science Foundation of Shandong Pro-vince,China(No.ZR2020MC194).
文摘There is an increasing demand for salmonid authentication due to the globalization of the salmonid trade.DNA barcoding and mini-DNA barcoding are widely used for identifying fish species based on a fragment of the mitochondrial cytochrome c oxidase subunit I(COI)sequence.In this study,rainbow trout(Oncorhynchus mykiss),steelhead trout(O.mykiss),and Atlantic salmon(Salmo salar)collected from two salmonid aquaculture bases in China were authenticated by DNA barcoding(about 650 bp)and mini-DNA barcoding(127 bp)to evaluate the accuracy of the two methods in the identification of different salmonid species.The results revealed that both methods could effectively distinguish O.mykiss and S.salar with 100%accuracy.However,the two methods failed to separate rainbow trout(O.mykiss)and steelhead trout(O.mykiss),which are the same species but cultured in different water environments.Moreover,salmonid samples from three main distribution channels in the Qingdao area(traditional supermarkets,online supermarkets,and sushi bars)were identified by the two methods.Substitution of S.salar with O.mykiss was discovered,and the 27.78%overall substitution rate of salmonids in the Qingdao area was higher than those in other regions reported in previous studies.In addition,the mislabeling rates of salmonids from traditional supermarkets,online supermarkets,and sushi bars were compared in this study.The mislabeling rate was significantly greater in sushi bars(50%)than in the other two channels(16.67%),suggesting that stronger monitoring and enforcement measures are necessary for the aquatic food catering industry.
