Objective Although many studies have examined the effects of ambient temperatures on mortality, little evidence is on health impacts of atmospheric pressure and relative humidity. This study aimed to assess the impact...Objective Although many studies have examined the effects of ambient temperatures on mortality, little evidence is on health impacts of atmospheric pressure and relative humidity. This study aimed to assess the impacts of atmospheric pressure and relative humidity on mortality in Guangzhou, China. Methods This study included 213,737 registered deaths during 2003-2011 in Guangzhou, China. A quasi-Poisson regression with a distributed lag non-linear model was used to assess the effects of atmospheric pressure/relative humidity. Results We found significant effect of low atmospheric pressure/relative humidity on mortality. There was a 1.79% （95% confidence interval： 0.38%-3.22%） increase in non-accidental mortality and a 2.27% （0.07%-4.51%） increase in cardiovascular mortality comparing the 5th and 25th percentile of atmospheric pressure. A 3.97% （0.67%-7.39%） increase in cardiovascular mortality was also observed comparing the 5th and 25th percentile of relative humidity. Women were more vulnerable to decrease in atmospheric pressure and relative humidity than men. Age and education attainment were also potential effect modifiers. Furthermore, low atmospheric pressure and relative humidity increased temperature-related mortality. Conclusion Both low atmospheric pressure and relative humidity are important risk factors of mortality. Our findings would be helpful to develop health risk assessment and climate policy interventions that would better protect vulnerable subgroups of the population.展开更多
Accelerated corrosion tests of the 7005-T4 aluminum alloy were conducted to determine a suitable service life prediction method by using alternating wet–dry cycles in three kinds of solutions. The morphology and comp...Accelerated corrosion tests of the 7005-T4 aluminum alloy were conducted to determine a suitable service life prediction method by using alternating wet–dry cycles in three kinds of solutions. The morphology and composition analysis of the corrosion product revealed that slight corrosion occurred on the surfaces of the samples immersed in a 0.25 wt% Na_2S_2O_8 solution. However, pitting corrosion occurred on the surfaces of the samples immersed in a 3.5 wt% NaCl solution, whereas exfoliation corrosion occurred on the surfaces of the samples immersed in a mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions. A power exponent relationship was observed between the mass loss and exposure time of the 7005-T4 aluminum alloy immersed in the three kinds of solutions. In the mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions, the mass loss of the aluminum alloy yielded the maximum value. Based on the calculation of the correlation coefficients, the alternating wet–dry procedure in a 3.5 wt% NaCl solution could be used to predict the corrosion behavior of 7005-T4 aluminum alloy exposed in the atmosphere of Qingdao, China. The prediction model is as follows: T = 104.28×t^(0.91), where T is the equivalent time and t is the exposure time.展开更多
Based on the case studies and statistical analysis of earthquake-related ionospheric disturbances mainly from DEMETER satellite, ground-based GPS and ionosounding data, this paper summarizes the statisw tical characte...Based on the case studies and statistical analysis of earthquake-related ionospheric disturbances mainly from DEMETER satellite, ground-based GPS and ionosounding data, this paper summarizes the statisw tical characteristics of earthquake-related ionospheric disturbances, including electromagnetic emissions, plasma perturbations and variation of energetic particle flux. According to the main results done by Chinese scientists, fusing with the existed study from global researches, seismo-ionospheric disturbances usually occurred a few days or hours before earthquake occurrence. Paralleling to these case studies, lithosphere-atmosphere-ionosphere （LAI） coupling mechanisms are checked and optimized. A thermo-electric model was proposed to explain the seismo-electromagnetic effects before earthquakes. A propagation model was put forward to explain the electromagnetic waves into the ionosphere. According to the requirement of earthquake prediction research, China seismo-electromagnetic satellite, the first space-based platform of Chinese earthquake stereoscopic observation system, is proposed and planned to launch at about the end of 2014. It focuses on checking the LAI model and distinguishing earthquake-related ionospheric disturbance. The preliminary design for the satellite will adopt CAST-2000 platform with eight payloads onboard. It is believed that the satellite will work together with the ground monitoring network to improve the capability to capture seismo-electromagnetic information, which is beneficial for earthquake monitoring and prediction researches.展开更多
In this paper we access the effects of two atmospheric variables (temperatureand relative humidity) on two important pollutants in the atmosphere(Nitrogen oxides (NOx) and carbon monoxide (CO)) by using one year(2016)...In this paper we access the effects of two atmospheric variables (temperatureand relative humidity) on two important pollutants in the atmosphere(Nitrogen oxides (NOx) and carbon monoxide (CO)) by using one year(2016) data of Addis Ababa. Temperature has impact on atmosphericmixing and cause for the reduction of NOx as temperature increases.There are positive correlation between temperature and CO concentrationfrom January to April with (R^2 = 0.69), negative correlation from Mayto August with (R2 = 0.92) and no correlation for the remaining months.NOx and CO have moderate positive and negative correlation with relativehumidity during the months January-April (R^2 = 0.294 for NOx and R^2 =0291 for CO) and in the months May-August are R2 = 0.97 and R2 = 0.15for NOx and CO respectively. But there are no clear correlation betweenthe NOx and CO with relative humidity from September-December.NOx concentrations during wet season was almost about twice that of thedry season, but no such difference was observed in the case of CO. Theseasonal average air temperature in wet season is relatively lower than dryseason. NOx exhibited positive and CO negative seasonal correlations withrelative humidity.展开更多
By using Lorenz’s moist general circulation model, a nonlinear and dissipative system describing atmospheric motion has been obtained in approximation of Low Order.The multiple equilibria and the transformation betwe...By using Lorenz’s moist general circulation model, a nonlinear and dissipative system describing atmospheric motion has been obtained in approximation of Low Order.The multiple equilibria and the transformation between the flow patterns of winter and summer, the latitudinal oscillation of subtropical high by thermal forcing and nonlinear interaction of general circulation are studied in this paper.The results show that the transformation of flow patterns is a discontinuous leaping, and is a process of resetting new flow pattern by rapid exchange inflow field.In the corresponding dry model, we cannot find the latitudinal oscillation of the center of subtropical high.In the moist model, after the thermal effect of water vapor is drawn into the model, nonlinear interaction appears between flow and heating fields.This effect helps to bring about the latitudinal oscillation of subtropical high.展开更多
基金funded by National Nature Science Foundation of China[81102207]Science and Technology Planning Project of Guangdong Province,China[2013B021800041]GUO Yu Ming is supported by NHMRC Centre for air quality and health research and evaluation,Australia[APP 1030259]
文摘Objective Although many studies have examined the effects of ambient temperatures on mortality, little evidence is on health impacts of atmospheric pressure and relative humidity. This study aimed to assess the impacts of atmospheric pressure and relative humidity on mortality in Guangzhou, China. Methods This study included 213,737 registered deaths during 2003-2011 in Guangzhou, China. A quasi-Poisson regression with a distributed lag non-linear model was used to assess the effects of atmospheric pressure/relative humidity. Results We found significant effect of low atmospheric pressure/relative humidity on mortality. There was a 1.79% （95% confidence interval： 0.38%-3.22%） increase in non-accidental mortality and a 2.27% （0.07%-4.51%） increase in cardiovascular mortality comparing the 5th and 25th percentile of atmospheric pressure. A 3.97% （0.67%-7.39%） increase in cardiovascular mortality was also observed comparing the 5th and 25th percentile of relative humidity. Women were more vulnerable to decrease in atmospheric pressure and relative humidity than men. Age and education attainment were also potential effect modifiers. Furthermore, low atmospheric pressure and relative humidity increased temperature-related mortality. Conclusion Both low atmospheric pressure and relative humidity are important risk factors of mortality. Our findings would be helpful to develop health risk assessment and climate policy interventions that would better protect vulnerable subgroups of the population.
基金supported by the National Key Research and Development Program of China (No. 2017YFB0702300)the National Natural Science Foundation of China (No. 51222106)+1 种基金the Fundamental Research Funds for the Central Universities of China (No. FRF-TP-14-011C1)the National Basic Research Program of China (973 Program, No. 2014CB643300)
文摘Accelerated corrosion tests of the 7005-T4 aluminum alloy were conducted to determine a suitable service life prediction method by using alternating wet–dry cycles in three kinds of solutions. The morphology and composition analysis of the corrosion product revealed that slight corrosion occurred on the surfaces of the samples immersed in a 0.25 wt% Na_2S_2O_8 solution. However, pitting corrosion occurred on the surfaces of the samples immersed in a 3.5 wt% NaCl solution, whereas exfoliation corrosion occurred on the surfaces of the samples immersed in a mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions. A power exponent relationship was observed between the mass loss and exposure time of the 7005-T4 aluminum alloy immersed in the three kinds of solutions. In the mixture of 0.25 wt% Na_2S_2O_8 and 3.5 wt% NaCl solutions, the mass loss of the aluminum alloy yielded the maximum value. Based on the calculation of the correlation coefficients, the alternating wet–dry procedure in a 3.5 wt% NaCl solution could be used to predict the corrosion behavior of 7005-T4 aluminum alloy exposed in the atmosphere of Qingdao, China. The prediction model is as follows: T = 104.28×t^(0.91), where T is the equivalent time and t is the exposure time.
基金funded by National Key Technology R&D Program in the 11th Five Year Plan of China (2008BAC35B00)the international cooperation project(2009DFA21480)
文摘Based on the case studies and statistical analysis of earthquake-related ionospheric disturbances mainly from DEMETER satellite, ground-based GPS and ionosounding data, this paper summarizes the statisw tical characteristics of earthquake-related ionospheric disturbances, including electromagnetic emissions, plasma perturbations and variation of energetic particle flux. According to the main results done by Chinese scientists, fusing with the existed study from global researches, seismo-ionospheric disturbances usually occurred a few days or hours before earthquake occurrence. Paralleling to these case studies, lithosphere-atmosphere-ionosphere （LAI） coupling mechanisms are checked and optimized. A thermo-electric model was proposed to explain the seismo-electromagnetic effects before earthquakes. A propagation model was put forward to explain the electromagnetic waves into the ionosphere. According to the requirement of earthquake prediction research, China seismo-electromagnetic satellite, the first space-based platform of Chinese earthquake stereoscopic observation system, is proposed and planned to launch at about the end of 2014. It focuses on checking the LAI model and distinguishing earthquake-related ionospheric disturbance. The preliminary design for the satellite will adopt CAST-2000 platform with eight payloads onboard. It is believed that the satellite will work together with the ground monitoring network to improve the capability to capture seismo-electromagnetic information, which is beneficial for earthquake monitoring and prediction researches.
文摘In this paper we access the effects of two atmospheric variables (temperatureand relative humidity) on two important pollutants in the atmosphere(Nitrogen oxides (NOx) and carbon monoxide (CO)) by using one year(2016) data of Addis Ababa. Temperature has impact on atmosphericmixing and cause for the reduction of NOx as temperature increases.There are positive correlation between temperature and CO concentrationfrom January to April with (R^2 = 0.69), negative correlation from Mayto August with (R2 = 0.92) and no correlation for the remaining months.NOx and CO have moderate positive and negative correlation with relativehumidity during the months January-April (R^2 = 0.294 for NOx and R^2 =0291 for CO) and in the months May-August are R2 = 0.97 and R2 = 0.15for NOx and CO respectively. But there are no clear correlation betweenthe NOx and CO with relative humidity from September-December.NOx concentrations during wet season was almost about twice that of thedry season, but no such difference was observed in the case of CO. Theseasonal average air temperature in wet season is relatively lower than dryseason. NOx exhibited positive and CO negative seasonal correlations withrelative humidity.
文摘By using Lorenz’s moist general circulation model, a nonlinear and dissipative system describing atmospheric motion has been obtained in approximation of Low Order.The multiple equilibria and the transformation between the flow patterns of winter and summer, the latitudinal oscillation of subtropical high by thermal forcing and nonlinear interaction of general circulation are studied in this paper.The results show that the transformation of flow patterns is a discontinuous leaping, and is a process of resetting new flow pattern by rapid exchange inflow field.In the corresponding dry model, we cannot find the latitudinal oscillation of the center of subtropical high.In the moist model, after the thermal effect of water vapor is drawn into the model, nonlinear interaction appears between flow and heating fields.This effect helps to bring about the latitudinal oscillation of subtropical high.
