This paper presents the nuclear analysis performance of the Chinese Fusion Engineering Test Reactor(CFETR)divertor region using the MCNP-5 Monte Carlo N-particles code in a 3 D geometry model.We assessed the nuclear r...This paper presents the nuclear analysis performance of the Chinese Fusion Engineering Test Reactor(CFETR)divertor region using the MCNP-5 Monte Carlo N-particles code in a 3 D geometry model.We assessed the nuclear responses of the divertor region component systems and evaluated their shielding capability,which can support the development strategy of the physical and engineering design of the CFETR.Model specification based on the latest CAD model of the CFETR divertor has been integrated into the CFETR MCNP reference model with a major/minor radius R=7.2 m/a=2.2 m in the 22.5°model,and a fusion-power range of around 1-1.5 GW.The nuclear heating and radiation damage of the divertor system are enhanced compared to that of the ITER and the earlier CFETR design.The initial nuclear responses of the toroidal field coil and vacuum vessel systems showed that the shielding of the current divertor design is not sufficient and optimization work has been carried out.We also carried out calculations and analysis using a hypothetical operating scenario of over 14 years.An excellent improvement in the nuclear performance has been obtained by the improved additional shielding block in the divertor region when referring to the ITER design limit,which can support the design of the future update of the divertor region systems of the CFETR.展开更多
Fluorine contaminates the environment. The study of fluorine contamination profile can be made easy by the use of nuclear analytic method. Measurement of prompt gamma emitted from bombarding fluorine polluted environm...Fluorine contaminates the environment. The study of fluorine contamination profile can be made easy by the use of nuclear analytic method. Measurement of prompt gamma emitted from bombarding fluorine polluted environmental sample with proton beam from accelerator provides rapid assessment of fluorine contamination. In this paper, 340 keV proton beam induced F 19 (P,αγ) O 16 reaction is performed, measurement of prompt gamma 6130 keV gives fluorine content in the soil and leaves of plants (parasol, cotton and glossy privet), taken from the fluorine polluted area.展开更多
This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are describ...This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are described in detail. The accuracy of our system has been checked up with the determination of standard reference materials. The preliminary results on correlations between trace elements in human tissues are discussed. Application of the method described in the paper gives evidence in favour of the PIXE as a good tool on environmental life elements and health studies.展开更多
The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shi...The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shielding module （BSM） were presented. The finite element analysis （FEA） and numerical calculation of the system were performed under the maximum loads. According to the American Society of Mechanical Engineers （ASME） criteria, the EM stress is far below the admissible failure boundary, which indicates that the system can resist the cooperative action of EM loads and device deadweight. The analysis could provide technical data and references for further analysis and optimized design of the system.展开更多
This paper deals with the toxic effects of selenium uptakes in the tissues of marine fish. The selenium concentration in skin, liver, muscle and gill of the fish were determined by proton induce X-ray emission (PIXE)....This paper deals with the toxic effects of selenium uptakes in the tissues of marine fish. The selenium concentration in skin, liver, muscle and gill of the fish were determined by proton induce X-ray emission (PIXE). The enzyme levels in liver tissues also were measured and evaluated . The results are shown that 50% lethal dose was LD50= 0. 29μg/g and it was found independent on the injected doses. The enzymes in serviving fish showed a gradual and complete recovery during the observation period. A very low Se uptake in muscle was found. The biological half lives of Se concentration in liver and gill were nearly identical, while the skin exhibited a half life 2. 5 times greater.展开更多
Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-seali...Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing efect.Nanosized magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing efect.Nuclear magnetic resonance spectrometry and scanning electron microscopy were adopted to study the efects of nanosized magnesia on the hydration of borehole-sealing cements used with diferent preparation methods.The results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration,and the mass fraction was positively correlated with the promotion efect.The use of diferent preparation methods did not change the water-phase distribution in the cement.When using the wet-mixing preparation method,nanosized magnesia promoted the induction,acceleration,and deceleration periods of hydration;when using the dry-mixing preparation method,the nanosized magnesia promoted the induction period of cement hydration,and the promotion efect was less obvious than that seen when using the wet-mixing method.When using the wet-mixing preparation method,the nanosized magnesia was uniformly dispersed,thus enlarging the surface area of the reaction,which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration reaction.When using the dry-mixing preparation method,the nanosized magnesia powders were dispersed nonuniformly and aggregated.Under these conditions,only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration,so only a small number of nucleation sites were provided for the hydration products of cement.This led to inconsistent hydration of cement pastes prepared using the dry-mixing method.The surface porosity of the cement prepared with the wet-mixing preparation method frst decreased and then increased with increases in the mass fraction of the nanosized magnesia.The cement surface exhibited compact hydration products and few pores,and the surface was relatively smooth.In comparison,the surface porosity of the cement prepared using the dry-mixing method fuctuated with increasing mass fraction of the nanosized magnesia,resulting in a rough cement surface and microfractures on some surfaces.The two preparation methods both reduced the surface porosity of the cement.The wet-mixing preparation was more efective and consistent in improving the compactness of the cement than the dry-mixing preparation.These results provide important guidance on the addition of nanosized magnesia in borehole-sealing engineering and the selection of cement preparation methods,and they also lay a solid foundation for realizing safe and efcient gas drainage.展开更多
Hydrogen distribution and content in diamond films deposited by DC arcjetunder gas recycling mode was evaluated by nuclear reaction analysis (NRA). The films werecharacterized using scanning electron microscopy, X-ray...Hydrogen distribution and content in diamond films deposited by DC arcjetunder gas recycling mode was evaluated by nuclear reaction analysis (NRA). The films werecharacterized using scanning electron microscopy, X-ray diffraction and Raman spectrometry. The NRAresults show that the hydrogen content in diamond films was approximately 0.6% (substratetemperature 770℃), and strongly depended on the substrate temperature. It was that the hydrogencontent increased with the increase of the substrate temperature. The possibility of hydrogentrapping in the films was also discussed.展开更多
The nuclear area (A)and nuclear roundness factor (NRF) of epithelial cells of 42 esophageal cancers and 10 normal esophagus’s were measured by morphometry and the results were compared with the extent of the tumor
Urban ecological resilience(UER)is a fundamental requirement for sustainable urban development.Ecosystem services(ESs)support urban resilience in many ways;however,it remains unknown how the various ES types affect UE...Urban ecological resilience(UER)is a fundamental requirement for sustainable urban development.Ecosystem services(ESs)support urban resilience in many ways;however,it remains unknown how the various ES types affect UER.In this study,10 ESs were selected to characterize the 4 types of ES in the Pearl River Delta urban agglomeration(PRD),and the InVEST model,CASA model,and nuclear density analysis were used to evaluate the various ESs.We used a morphological resilience-density resilienceeconomic resilience framework to assess UER,and the structure equation model was used to explore the effects of ESs on UER.展开更多
基金supported by the National Key Research and Development Program of China(Nos.2017YFE0300500,2017YFE0300503)。
文摘This paper presents the nuclear analysis performance of the Chinese Fusion Engineering Test Reactor(CFETR)divertor region using the MCNP-5 Monte Carlo N-particles code in a 3 D geometry model.We assessed the nuclear responses of the divertor region component systems and evaluated their shielding capability,which can support the development strategy of the physical and engineering design of the CFETR.Model specification based on the latest CAD model of the CFETR divertor has been integrated into the CFETR MCNP reference model with a major/minor radius R=7.2 m/a=2.2 m in the 22.5°model,and a fusion-power range of around 1-1.5 GW.The nuclear heating and radiation damage of the divertor system are enhanced compared to that of the ITER and the earlier CFETR design.The initial nuclear responses of the toroidal field coil and vacuum vessel systems showed that the shielding of the current divertor design is not sufficient and optimization work has been carried out.We also carried out calculations and analysis using a hypothetical operating scenario of over 14 years.An excellent improvement in the nuclear performance has been obtained by the improved additional shielding block in the divertor region when referring to the ITER design limit,which can support the design of the future update of the divertor region systems of the CFETR.
文摘Fluorine contaminates the environment. The study of fluorine contamination profile can be made easy by the use of nuclear analytic method. Measurement of prompt gamma emitted from bombarding fluorine polluted environmental sample with proton beam from accelerator provides rapid assessment of fluorine contamination. In this paper, 340 keV proton beam induced F 19 (P,αγ) O 16 reaction is performed, measurement of prompt gamma 6130 keV gives fluorine content in the soil and leaves of plants (parasol, cotton and glossy privet), taken from the fluorine polluted area.
文摘This paper deals with the determination of trace elements in normal human hair, liver and kidney by Proton Induced X-ray Emission (PIXE) analysis. Sampling, specimen preparation and experimental procedures are described in detail. The accuracy of our system has been checked up with the determination of standard reference materials. The preliminary results on correlations between trace elements in human tissues are discussed. Application of the method described in the paper gives evidence in favour of the PIXE as a good tool on environmental life elements and health studies.
文摘The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shielding module （BSM） were presented. The finite element analysis （FEA） and numerical calculation of the system were performed under the maximum loads. According to the American Society of Mechanical Engineers （ASME） criteria, the EM stress is far below the admissible failure boundary, which indicates that the system can resist the cooperative action of EM loads and device deadweight. The analysis could provide technical data and references for further analysis and optimized design of the system.
文摘This paper deals with the toxic effects of selenium uptakes in the tissues of marine fish. The selenium concentration in skin, liver, muscle and gill of the fish were determined by proton induce X-ray emission (PIXE). The enzyme levels in liver tissues also were measured and evaluated . The results are shown that 50% lethal dose was LD50= 0. 29μg/g and it was found independent on the injected doses. The enzymes in serviving fish showed a gradual and complete recovery during the observation period. A very low Se uptake in muscle was found. The biological half lives of Se concentration in liver and gill were nearly identical, while the skin exhibited a half life 2. 5 times greater.
基金supported by“Overall Rationing System”Project of Chongqing Talent Program(cstc2022ycjh-bgzxm0077)the National Natural Science Foundation of China(52074041)+1 种基金Natural Science Foundation of Chongqing,China(cstc2020jcyj-msxmX0836)Fundamental Research Funds for the Central Universities(2020CDJ-LHZZ-002),which are gratefully acknowledged.
文摘Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing efect.Nanosized magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing efect.Nuclear magnetic resonance spectrometry and scanning electron microscopy were adopted to study the efects of nanosized magnesia on the hydration of borehole-sealing cements used with diferent preparation methods.The results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration,and the mass fraction was positively correlated with the promotion efect.The use of diferent preparation methods did not change the water-phase distribution in the cement.When using the wet-mixing preparation method,nanosized magnesia promoted the induction,acceleration,and deceleration periods of hydration;when using the dry-mixing preparation method,the nanosized magnesia promoted the induction period of cement hydration,and the promotion efect was less obvious than that seen when using the wet-mixing method.When using the wet-mixing preparation method,the nanosized magnesia was uniformly dispersed,thus enlarging the surface area of the reaction,which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration reaction.When using the dry-mixing preparation method,the nanosized magnesia powders were dispersed nonuniformly and aggregated.Under these conditions,only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration,so only a small number of nucleation sites were provided for the hydration products of cement.This led to inconsistent hydration of cement pastes prepared using the dry-mixing method.The surface porosity of the cement prepared with the wet-mixing preparation method frst decreased and then increased with increases in the mass fraction of the nanosized magnesia.The cement surface exhibited compact hydration products and few pores,and the surface was relatively smooth.In comparison,the surface porosity of the cement prepared using the dry-mixing method fuctuated with increasing mass fraction of the nanosized magnesia,resulting in a rough cement surface and microfractures on some surfaces.The two preparation methods both reduced the surface porosity of the cement.The wet-mixing preparation was more efective and consistent in improving the compactness of the cement than the dry-mixing preparation.These results provide important guidance on the addition of nanosized magnesia in borehole-sealing engineering and the selection of cement preparation methods,and they also lay a solid foundation for realizing safe and efcient gas drainage.
文摘Hydrogen distribution and content in diamond films deposited by DC arcjetunder gas recycling mode was evaluated by nuclear reaction analysis (NRA). The films werecharacterized using scanning electron microscopy, X-ray diffraction and Raman spectrometry. The NRAresults show that the hydrogen content in diamond films was approximately 0.6% (substratetemperature 770℃), and strongly depended on the substrate temperature. It was that the hydrogencontent increased with the increase of the substrate temperature. The possibility of hydrogentrapping in the films was also discussed.
文摘The nuclear area (A)and nuclear roundness factor (NRF) of epithelial cells of 42 esophageal cancers and 10 normal esophagus’s were measured by morphometry and the results were compared with the extent of the tumor
基金supported by Chaohu University for the Start-UP grant(grant number KYQD-2023068)the National Natural Science Foundation of China(grant number42376226)
文摘Urban ecological resilience(UER)is a fundamental requirement for sustainable urban development.Ecosystem services(ESs)support urban resilience in many ways;however,it remains unknown how the various ES types affect UER.In this study,10 ESs were selected to characterize the 4 types of ES in the Pearl River Delta urban agglomeration(PRD),and the InVEST model,CASA model,and nuclear density analysis were used to evaluate the various ESs.We used a morphological resilience-density resilienceeconomic resilience framework to assess UER,and the structure equation model was used to explore the effects of ESs on UER.
