Introduction:To establish baseline radioactivity levels and ensure the safety of drinking water quality in China,gross alpha and gross beta radioactivity levels in drinking water were surveyed from 2012 to 2024.Method...Introduction:To establish baseline radioactivity levels and ensure the safety of drinking water quality in China,gross alpha and gross beta radioactivity levels in drinking water were surveyed from 2012 to 2024.Methods:The surveillance was conducted through the national monitoring system for radioactivity in drinking water,organized by The National Institute for Radiological Protection(NIRP)during the period 2012–2024.Drinking water samples were collected and pretreated in accordance with a unified protocol,and radioactivity was determined using alpha/beta counting systems by local laboratories.Results:From 2012 to 2024,over 11,000 drinking water samples were collected and analyzed across 29 provinces,including areas surrounding nuclear power plants.The mean concentration ranges of gross alpha and gross beta radioactivity levels in all regions and various water bodies were 0.01–0.17 Bq/L and 0.05–0.38 Bq/L,respectively,all of which are below the guidance values specified in the national standard GB 5749(0.5 Bq/L for gross alpha and 1 Bq/L for gross beta).However,the gross alpha and gross beta activity levels in well water were higher than those in other water bodies.The results indicate that radioactivity in drinking water primarily originates from natural radionuclides.Conclusions:Drinking water in China maintains normal background levels of radioactivity.Nuclear power plant operations do not seem to have an impact on surrounding water sources.展开更多
The covID-19 outbreak has brought unprecedented social attention to economic uncertainty and negative interest rate policy(NIRP).How does uncertainty affect economic activity,and how effective is a NIRP based on centr...The covID-19 outbreak has brought unprecedented social attention to economic uncertainty and negative interest rate policy(NIRP).How does uncertainty affect economic activity,and how effective is a NIRP based on central bank digital currency(CBDC)?To answer the two questions,we constructed a dynamic stochastic general equilibrium(DSGE)model that accommodates sticky prices and wages.The results indicated:(i)Economic uncertainty has substantially reduced investment,output,wage,and loans,which increases unemployment risk.In the short term,it has triggered impulsive consumption by households,while consumption has fallen into a slump in the long run.(ii)After suffering an uncertainty shock,the economy entered short-term stagflation and long-term deflation.The short-term stagflation was mainly caused by resident wage adjustment,and the long-term deflation was due to the decline in effective demand caused by unemployment risk.(ii)CBDC could eliminate the zero lower bound(ZLB)constraint,thereby improving the effectiveness of NIRP.Compared with traditional currency,CBDCbased NIRP could more effectively smooth macroeconomic fluctuations and alleviate the negative impact of an uncertainty shock,which is more conducive to restoring market confidence and promoting economic recovery.展开更多
文摘Introduction:To establish baseline radioactivity levels and ensure the safety of drinking water quality in China,gross alpha and gross beta radioactivity levels in drinking water were surveyed from 2012 to 2024.Methods:The surveillance was conducted through the national monitoring system for radioactivity in drinking water,organized by The National Institute for Radiological Protection(NIRP)during the period 2012–2024.Drinking water samples were collected and pretreated in accordance with a unified protocol,and radioactivity was determined using alpha/beta counting systems by local laboratories.Results:From 2012 to 2024,over 11,000 drinking water samples were collected and analyzed across 29 provinces,including areas surrounding nuclear power plants.The mean concentration ranges of gross alpha and gross beta radioactivity levels in all regions and various water bodies were 0.01–0.17 Bq/L and 0.05–0.38 Bq/L,respectively,all of which are below the guidance values specified in the national standard GB 5749(0.5 Bq/L for gross alpha and 1 Bq/L for gross beta).However,the gross alpha and gross beta activity levels in well water were higher than those in other water bodies.The results indicate that radioactivity in drinking water primarily originates from natural radionuclides.Conclusions:Drinking water in China maintains normal background levels of radioactivity.Nuclear power plant operations do not seem to have an impact on surrounding water sources.
基金the National Planning Office of Philosophy and Social Science of China(Grant No.21BJY206)。
文摘The covID-19 outbreak has brought unprecedented social attention to economic uncertainty and negative interest rate policy(NIRP).How does uncertainty affect economic activity,and how effective is a NIRP based on central bank digital currency(CBDC)?To answer the two questions,we constructed a dynamic stochastic general equilibrium(DSGE)model that accommodates sticky prices and wages.The results indicated:(i)Economic uncertainty has substantially reduced investment,output,wage,and loans,which increases unemployment risk.In the short term,it has triggered impulsive consumption by households,while consumption has fallen into a slump in the long run.(ii)After suffering an uncertainty shock,the economy entered short-term stagflation and long-term deflation.The short-term stagflation was mainly caused by resident wage adjustment,and the long-term deflation was due to the decline in effective demand caused by unemployment risk.(ii)CBDC could eliminate the zero lower bound(ZLB)constraint,thereby improving the effectiveness of NIRP.Compared with traditional currency,CBDCbased NIRP could more effectively smooth macroeconomic fluctuations and alleviate the negative impact of an uncertainty shock,which is more conducive to restoring market confidence and promoting economic recovery.
