The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron m...The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron microscopy,and energy dispersion spectroscopy.The results demonstrate that the addition of CaTiO_(3)corrosion inhibitor efficiently passivates the carbon anode and leads to the formation of a dense CaTiO_(3)layer during the electrolysis process in molten CaCl_(2)-CaO.Subsequently,the passivated carbon anode effectively undergoes the oxygen evolution reaction,with an optimal current density for passivation identified at 400 m A/cm^(2).Comprehensive investigations,including CaTiO_(3)solubility tests in molten CaCl_(2)-CaO and numerical modeling of the stability of complex ionic structures,provide compelling evidence supporting“complexation-precipitation”passivation mechanism.This mechanism involves the initial formation of a complex containing TiO_(2)·nCaO by CaTiO_(3)and CaO,which subsequently decomposes to yield CaTiO_(3),firmly coating the surface of the carbon anode.In practical applications,the integration of CaTiO_(3)corrosion inhibitor with the carbon anode leads to the successful preparation of the FeCoNiCrMn high-entropy alloy without carbon contamination in the molten CaCl_(2)-CaO.展开更多
An adaptable and compact fast pulse sampling module was developed for the neutron–gamma discrimination. The developed module is well suited for low-cost and low-power consumption applications. It is based on the Domi...An adaptable and compact fast pulse sampling module was developed for the neutron–gamma discrimination. The developed module is well suited for low-cost and low-power consumption applications. It is based on the Domino Ring Sampler 4(DRS4) chip, which offers fast sampling speeds up to 5.12 giga samples per second(GSPS) to digitize pulses from front-end detectors. The high-resolution GSPS data is useful for obtaining precise real-time neutron–gamma discrimination results directly in this module. In this study, we have implemented real-time data analysis in a field programmable gate array. Real-time data analysis involves two aspects: digital waveform integral and digital pulse shape discrimination(PSD). It can significantly reduce the system dead time and data rate processed offline. Plastic scintillators(EJ-299-33), which have proven capable of PSD, were adopted as neutron detectors in the experiments. A photomultiplier tube(PMT)(model #XP2020) was coupled to one end of a detector to collect the output light from it. The pulse output from the anode of the PMT was directly passed onto the fast sampling module. The fast pulse sampling module was operated at 1 GSPS and 2 GSPS in these experiments, and the AmBe-241 source was used to examine the neutron–gamma discrimination quality. The PSD results with different sampling rates and energy thresholds were evaluated. The figure of merit(FOM) was used to describe the neutron–gamma discrimination quality. The best FOM value of 0.91 was obtained at 2 GSPS and 1 GSPS sampling rates with an energy threshold of 1.5 MeV_(ee)(electron equivalent).展开更多
A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circui...A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circuit and charge-to-time conversion(QTC) circuit.The 64 outputs of a Hamamatsu H8500 position-sensitive photomultiplier tube were processed,and three digital pulses were generated.The widths of digital pulses were determined using the time-to-digital converter in an field programmable gate array.The energy and position information of incident y-rays is estimated based on the proportionality between the width of digital pulses and input charge created by y-photons.A prototype was built using discrete components and tested,and the energy and position resolutions were improved compared with that obtained with standard ADCs.This method greatly simplifies the front-end electronics and the digital interface.It enables a compact electronics system and an easy integration into an ASIC.展开更多
Objective This study was to examine the relationship between socioeconomic status and the incidence and mortality of non-Hodgkin lymphoma(NHL).Methods We compared the age-standardized incidence rate(ASIR),age-standard...Objective This study was to examine the relationship between socioeconomic status and the incidence and mortality of non-Hodgkin lymphoma(NHL).Methods We compared the age-standardized incidence rate(ASIR),age-standardized mortality rate(ASMR),and the ASMR to ASIR ratio(MIR)at national and regional levels and studied the correlation between the MIR and the human development index(HDI)in 2012 and 2018.Results The highest ASIR was in North America in 2012 and in Australia in 2018,and the lowest ASIR was in Central and South Asia in both 2012 and 2018.The highest ASMR was in North Africa in both 2012 and 2018,and the lowest ASMR was in Eastern Asia and South-Central Asia in 2012 and in South-Central Asia in 2018.The lowest MIR was in Australia in both 2012 and 2018,and the highest MIR was in Western Africa in both 2012 and 2018.HDI was strongly negatively correlated with MIR(r:−0.8810,P<0.0001,2012;r:−0.8895,P<0.0001,2018).Compared to the 2012 data,the MIR in the intermediate HDI countries significantly deceased and the HDI in low and high HDI countries significantly increased in 2018.Conclusion The MIR is negatively correlated with HDI.Increasing the HDI in low and intermediate HDI countries may reduce the MIR and increase the survival of patients with NHL.展开更多
Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintill...Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintillation fiber array coupled to 2×2 Hamamatsu H8500C position-sensitive photomultiplier tubes by optical fibers.The fiber array is fabricated with 0.5 mm×3 mm fibers and 3-mm square fibers.Results Due to the combined application of different sizes of fibers,the detector can broaden energy dynamic range and meanwhile have good detection efficiency.The method of the combined application of different sizes of plastic fibers in the array may provide a solution to measure wider energy range of solar neutrons.Conclusion In this paper,we used FLUKA to simulate the performance of the detector model and report the results of experimental studies with neutrons from a pulsed D-T neutron.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52031008,51874211,21673162,51325102,U22B2071)the International Science and Technology Cooperation Program of China(No.2015DFA90750)the China Postdoctoral Science Foundation(No.2020M682468)。
文摘The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron microscopy,and energy dispersion spectroscopy.The results demonstrate that the addition of CaTiO_(3)corrosion inhibitor efficiently passivates the carbon anode and leads to the formation of a dense CaTiO_(3)layer during the electrolysis process in molten CaCl_(2)-CaO.Subsequently,the passivated carbon anode effectively undergoes the oxygen evolution reaction,with an optimal current density for passivation identified at 400 m A/cm^(2).Comprehensive investigations,including CaTiO_(3)solubility tests in molten CaCl_(2)-CaO and numerical modeling of the stability of complex ionic structures,provide compelling evidence supporting“complexation-precipitation”passivation mechanism.This mechanism involves the initial formation of a complex containing TiO_(2)·nCaO by CaTiO_(3)and CaO,which subsequently decomposes to yield CaTiO_(3),firmly coating the surface of the carbon anode.In practical applications,the integration of CaTiO_(3)corrosion inhibitor with the carbon anode leads to the successful preparation of the FeCoNiCrMn high-entropy alloy without carbon contamination in the molten CaCl_(2)-CaO.
基金supported by the Instrument Developing Project of the Chinese Academy of Sciences(No.29201707)
文摘An adaptable and compact fast pulse sampling module was developed for the neutron–gamma discrimination. The developed module is well suited for low-cost and low-power consumption applications. It is based on the Domino Ring Sampler 4(DRS4) chip, which offers fast sampling speeds up to 5.12 giga samples per second(GSPS) to digitize pulses from front-end detectors. The high-resolution GSPS data is useful for obtaining precise real-time neutron–gamma discrimination results directly in this module. In this study, we have implemented real-time data analysis in a field programmable gate array. Real-time data analysis involves two aspects: digital waveform integral and digital pulse shape discrimination(PSD). It can significantly reduce the system dead time and data rate processed offline. Plastic scintillators(EJ-299-33), which have proven capable of PSD, were adopted as neutron detectors in the experiments. A photomultiplier tube(PMT)(model #XP2020) was coupled to one end of a detector to collect the output light from it. The pulse output from the anode of the PMT was directly passed onto the fast sampling module. The fast pulse sampling module was operated at 1 GSPS and 2 GSPS in these experiments, and the AmBe-241 source was used to examine the neutron–gamma discrimination quality. The PSD results with different sampling rates and energy thresholds were evaluated. The figure of merit(FOM) was used to describe the neutron–gamma discrimination quality. The best FOM value of 0.91 was obtained at 2 GSPS and 1 GSPS sampling rates with an energy threshold of 1.5 MeV_(ee)(electron equivalent).
基金supported by the National Key Scientific Instrument and Equipment Development Project(No.2011YQ120096)National Instrumentation Program(No.2013YQ030629)the National Natural Science Foundation of China(Nos.11475206,11175200 and11205170)
文摘A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circuit and charge-to-time conversion(QTC) circuit.The 64 outputs of a Hamamatsu H8500 position-sensitive photomultiplier tube were processed,and three digital pulses were generated.The widths of digital pulses were determined using the time-to-digital converter in an field programmable gate array.The energy and position information of incident y-rays is estimated based on the proportionality between the width of digital pulses and input charge created by y-photons.A prototype was built using discrete components and tested,and the energy and position resolutions were improved compared with that obtained with standard ADCs.This method greatly simplifies the front-end electronics and the digital interface.It enables a compact electronics system and an easy integration into an ASIC.
基金supported by the National Natural Science Foundation of China(No.81700147).
文摘Objective This study was to examine the relationship between socioeconomic status and the incidence and mortality of non-Hodgkin lymphoma(NHL).Methods We compared the age-standardized incidence rate(ASIR),age-standardized mortality rate(ASMR),and the ASMR to ASIR ratio(MIR)at national and regional levels and studied the correlation between the MIR and the human development index(HDI)in 2012 and 2018.Results The highest ASIR was in North America in 2012 and in Australia in 2018,and the lowest ASIR was in Central and South Asia in both 2012 and 2018.The highest ASMR was in North Africa in both 2012 and 2018,and the lowest ASMR was in Eastern Asia and South-Central Asia in 2012 and in South-Central Asia in 2018.The lowest MIR was in Australia in both 2012 and 2018,and the highest MIR was in Western Africa in both 2012 and 2018.HDI was strongly negatively correlated with MIR(r:−0.8810,P<0.0001,2012;r:−0.8895,P<0.0001,2018).Compared to the 2012 data,the MIR in the intermediate HDI countries significantly deceased and the HDI in low and high HDI countries significantly increased in 2018.Conclusion The MIR is negatively correlated with HDI.Increasing the HDI in low and intermediate HDI countries may reduce the MIR and increase the survival of patients with NHL.
文摘Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintillation fiber array coupled to 2×2 Hamamatsu H8500C position-sensitive photomultiplier tubes by optical fibers.The fiber array is fabricated with 0.5 mm×3 mm fibers and 3-mm square fibers.Results Due to the combined application of different sizes of fibers,the detector can broaden energy dynamic range and meanwhile have good detection efficiency.The method of the combined application of different sizes of plastic fibers in the array may provide a solution to measure wider energy range of solar neutrons.Conclusion In this paper,we used FLUKA to simulate the performance of the detector model and report the results of experimental studies with neutrons from a pulsed D-T neutron.
