The KCI：Eu2＋ system response to UV-C was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It...The KCI：Eu2＋ system response to UV-C was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It was found that after UV-C irra.diation, OSL was produced on a wide band of visible wavelengths with decay time that varied by several orders of magnitude depending on the Eu2＋ aggregation state. In spite of the low intensity of solar UV-C reaching the Earth＇s surface in Madrid （40° N, 700 m a.s.1.）, it was possible to measure the UV-C radiation dose at 6：48 solar time by using the TL response of the KCI：Eu2＋ system and differentiate it from the ambient beta radiation dose.展开更多
The radiation environment on the surface of Mars is a potential threat for future manned exploration missions to this planet.In this study,a simple geometrical model was built for simulating the radiation environment ...The radiation environment on the surface of Mars is a potential threat for future manned exploration missions to this planet.In this study,a simple geometrical model was built for simulating the radiation environment on the Mars surface caused by galactic cosmic rays;the model was built and studied using the Geant4 toolkit.The simulation results were compared with the data reported by a radiation assessment detector(RAD).The simulated spectra of neutrons,photons,protons,α particles,and particle groups Z=3-5,Z=6-8,Z=9-13,and Z=14-24 were in a reasonable agreement with the RAD data.However,for deuterons,tritons,and 3He,the simulations yielded much smaller values than for the corresponding RAD data.In addition,the particles’spectra within the 90 zenith angle were also obtained.Based on these spectra,we calculated the radiation dose that would have been received by an average human body on Mars.The distribution of the dose throughout the human body was not uniform.The absorbed and equivalent doses for the brain were the highest among all of the organs,reaching 62.0±1.7 mGy/y and 234.1±8.0 mSv/y,respectively.The average absorbed and equivalent doses for the entire body were approximately 44 mGy/y and 153 mSv/y,respectively.Further analysis revealed that most of the radiation dose was owing to a particles,protons,and heavy ions.We then studied the shielding effect of the Mars soil with respect to the radiation.The body dose decreased significantly with increasing soil depth.At the depth of 1.5 m,the effective dose for the entire body was 17.9±2.4 mSv/y,lower than the dose limit for occupational exposure.At the depth of 3 m,the effective dose to the body was 2.7±1.0 mSv/y,still higher than the accepted dose limit.展开更多
Knowledge of the electromagnetic radiation characteristics of 5G base stations under diferent circumstances is useful for risk prevention,assessment,and management.This paper selects several typical scenes(Open spaces...Knowledge of the electromagnetic radiation characteristics of 5G base stations under diferent circumstances is useful for risk prevention,assessment,and management.This paper selects several typical scenes(Open spaces,building concentration areas,user and building intensive areas)for electromagnetic radiation monitoring,and analyzes the relationship between ambient radiated power density and base station background.The results show that the factors that have signifcant impacts on the environmental radiation power density of 5G base stations including transmission distance,base station distribution,user density,building refection superposition and so on.The radiation energy decays rapidly with distance.When the density of the building distribution is too large,the superposition efect caused by the refected wave is concentrated at the distance of 50-70 meters.When the user density decreases(the superposition efect of refected waves decreases),the 5G monitoring value follows the direct wave attenuation law and decreases rapidly with the increase of distance.Points with higher measured radiation in the simple access condition also had higher measured radiation in the high-speed download condition.With the popularization of 5G mobile phones and the increase of user density,the resource utilization of a single user will decline to the normal operation state,and the radiation environmental impact will be further reduced.展开更多
An imported energy spectrum analyzer is powerful, but English operation interface is not easy to use. According to actual work needs, preliminary design of the Chinese energy spectrum analysis system is introduced in ...An imported energy spectrum analyzer is powerful, but English operation interface is not easy to use. According to actual work needs, preliminary design of the Chinese energy spectrum analysis system is introduced in the paper.展开更多
Missions flying to giant planets frequently provide telemetry data after substantial time lag. Determination of crucial environmental characteristic sometimes detrimental for the mission health may be further delayed ...Missions flying to giant planets frequently provide telemetry data after substantial time lag. Determination of crucial environmental characteristic sometimes detrimental for the mission health may be further delayed by duration of subsequent data analysis. We propose a fast method used in-flight to assess the electron total ionizing dose and dose rate onboard of the JUICE ESA mission to JUPITER. The procedure provides estimated values of dose rate behind various thickness of shielding using counting rates from the electron telescope EHD of the RADEM radiation hard electron monitor instrument onboard JUICE.展开更多
The WRNM(wide range neutron monitoring)is a newly developed neutron monitoring channel which was initially conceived as a means to meet Regulatory Guide 1.97 requirements for post-accident neutron monitoring.The scope...The WRNM(wide range neutron monitoring)is a newly developed neutron monitoring channel which was initially conceived as a means to meet Regulatory Guide 1.97 requirements for post-accident neutron monitoring.The scope was expanded to include the startup monitoring function with the aim of replacing both the source and IRMs(intermediate range monitors)in BWRs(boiling water reactors).The WRNMs,consisting of a newly designed fixed incore regenerative sensor and new electronics,which include both counting and MSV(mean square voltage)channels,have been tested in several reactors and its capabilities have been confirmed.The channel will cover the neutron flux range from 103 nv to 1.5×103 nv;it has greater than 1 decade overlap between the counting and MSV channels.Because of the regenerative fissile coating the sensor,even though fixed incore,has a life of approximately 6.0 full power years in a 51 kW/L BWR and similar situation has been proposed for newly designed small modular reactor such as BWRX-300 of General Electric Hitachi reactor.展开更多
文摘The KCI：Eu2＋ system response to UV-C was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It was found that after UV-C irra.diation, OSL was produced on a wide band of visible wavelengths with decay time that varied by several orders of magnitude depending on the Eu2＋ aggregation state. In spite of the low intensity of solar UV-C reaching the Earth＇s surface in Madrid （40° N, 700 m a.s.1.）, it was possible to measure the UV-C radiation dose at 6：48 solar time by using the TL response of the KCI：Eu2＋ system and differentiate it from the ambient beta radiation dose.
基金supported by the National Natural Science Foundation of China(Nos.12035011,11535004,11905103,11947211,11975167,11761161001,11565010,11961141003,11805103,11673075,11303107,11120101005,and 11235001)the National Key R&D Program of China(Nos.2018YFA0404403 and 2016YFE0129300)+2 种基金the Science and Technology Development Fund of Macao(No.008/2017/AFJ)the Fundamental Research Funds for the Central Universities(Nos.22120210138 and 22120200101)by the China Post-doctoral Science Foundation(Nos.2019M660095 and 2020T130478)。
文摘The radiation environment on the surface of Mars is a potential threat for future manned exploration missions to this planet.In this study,a simple geometrical model was built for simulating the radiation environment on the Mars surface caused by galactic cosmic rays;the model was built and studied using the Geant4 toolkit.The simulation results were compared with the data reported by a radiation assessment detector(RAD).The simulated spectra of neutrons,photons,protons,α particles,and particle groups Z=3-5,Z=6-8,Z=9-13,and Z=14-24 were in a reasonable agreement with the RAD data.However,for deuterons,tritons,and 3He,the simulations yielded much smaller values than for the corresponding RAD data.In addition,the particles’spectra within the 90 zenith angle were also obtained.Based on these spectra,we calculated the radiation dose that would have been received by an average human body on Mars.The distribution of the dose throughout the human body was not uniform.The absorbed and equivalent doses for the brain were the highest among all of the organs,reaching 62.0±1.7 mGy/y and 234.1±8.0 mSv/y,respectively.The average absorbed and equivalent doses for the entire body were approximately 44 mGy/y and 153 mSv/y,respectively.Further analysis revealed that most of the radiation dose was owing to a particles,protons,and heavy ions.We then studied the shielding effect of the Mars soil with respect to the radiation.The body dose decreased significantly with increasing soil depth.At the depth of 1.5 m,the effective dose for the entire body was 17.9±2.4 mSv/y,lower than the dose limit for occupational exposure.At the depth of 3 m,the effective dose to the body was 2.7±1.0 mSv/y,still higher than the accepted dose limit.
基金supported by the Ecological Environment Research Project of Jiangsu Province:5G Base station radiation environment monitoring technology and environmental impact research(No.2020014).
文摘Knowledge of the electromagnetic radiation characteristics of 5G base stations under diferent circumstances is useful for risk prevention,assessment,and management.This paper selects several typical scenes(Open spaces,building concentration areas,user and building intensive areas)for electromagnetic radiation monitoring,and analyzes the relationship between ambient radiated power density and base station background.The results show that the factors that have signifcant impacts on the environmental radiation power density of 5G base stations including transmission distance,base station distribution,user density,building refection superposition and so on.The radiation energy decays rapidly with distance.When the density of the building distribution is too large,the superposition efect caused by the refected wave is concentrated at the distance of 50-70 meters.When the user density decreases(the superposition efect of refected waves decreases),the 5G monitoring value follows the direct wave attenuation law and decreases rapidly with the increase of distance.Points with higher measured radiation in the simple access condition also had higher measured radiation in the high-speed download condition.With the popularization of 5G mobile phones and the increase of user density,the resource utilization of a single user will decline to the normal operation state,and the radiation environmental impact will be further reduced.
文摘An imported energy spectrum analyzer is powerful, but English operation interface is not easy to use. According to actual work needs, preliminary design of the Chinese energy spectrum analysis system is introduced in the paper.
文摘Missions flying to giant planets frequently provide telemetry data after substantial time lag. Determination of crucial environmental characteristic sometimes detrimental for the mission health may be further delayed by duration of subsequent data analysis. We propose a fast method used in-flight to assess the electron total ionizing dose and dose rate onboard of the JUICE ESA mission to JUPITER. The procedure provides estimated values of dose rate behind various thickness of shielding using counting rates from the electron telescope EHD of the RADEM radiation hard electron monitor instrument onboard JUICE.
文摘The WRNM(wide range neutron monitoring)is a newly developed neutron monitoring channel which was initially conceived as a means to meet Regulatory Guide 1.97 requirements for post-accident neutron monitoring.The scope was expanded to include the startup monitoring function with the aim of replacing both the source and IRMs(intermediate range monitors)in BWRs(boiling water reactors).The WRNMs,consisting of a newly designed fixed incore regenerative sensor and new electronics,which include both counting and MSV(mean square voltage)channels,have been tested in several reactors and its capabilities have been confirmed.The channel will cover the neutron flux range from 103 nv to 1.5×103 nv;it has greater than 1 decade overlap between the counting and MSV channels.Because of the regenerative fissile coating the sensor,even though fixed incore,has a life of approximately 6.0 full power years in a 51 kW/L BWR and similar situation has been proposed for newly designed small modular reactor such as BWRX-300 of General Electric Hitachi reactor.
