On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low backgrou...On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low background noise environment. A newly acoustic test section is presented in this paper, of which the contour is similar as the closed test section, and the wall is fabricated by the fiber fabric, both the characteristics of closed and open jet test section of conventional wind tunnel are combined in it. By thoroughly researching on the acoustics and aerodynamics of this acoustically transparent test section, significant progress in reducing the background noises in test section and improving the ratio of energy of the wind tunnel and some other aspects have been achieved. Acoustically transparent test section behaves better in acoustics and aerodynamics than conventional acoustic test section because of their high definition in detecting the sound sources and great performance in transmitting sounds.展开更多
Atmospheric particulate matter(PM)is a dominant source of air pollution,in particular,molecules less than 2.5μm in diameter,endangering human health.An estimated 2.1 million deaths from exposure to PM2.5 and 700,000 ...Atmospheric particulate matter(PM)is a dominant source of air pollution,in particular,molecules less than 2.5μm in diameter,endangering human health.An estimated 2.1 million deaths from exposure to PM2.5 and 700,000 cases of respiratory disease caused by atmospheric pollution were reported on an annual basis.The main components of PM2.5 include heavy metal elements,water-soluble ions,carbon aerosols,ozone,and organic compounds.Per-and polyfluoroalkyl substances(PFASs)are a large group of representative pollutants among the organic compounds absorbed in PM2.5.PFASs are widely used in industrial production and hardly degraded in the environment,resulting in their accumulation in water,food,and air,and abosorbed by humans via ingestion and inhalation.On the other hand,accumulation of PFAS in the human body is proving to be associated with some unfavorable health outcomes,whereas the mechanisms underlying the effects of PFAS exposure on human lung diseases remain unclear at present.The toxicological effects of organic components are a significant focus of research.This review will fix our attention on the changes in the distribution,composition,and content of PFAS in PM2.5 by location and year,and provide an overview on the influence of PM2.5 and PFAS on lung health,with indications of possible synergistic adverse effects of PM2.5 and PFAS on pulmonary homeostasis.展开更多
文摘On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low background noise environment. A newly acoustic test section is presented in this paper, of which the contour is similar as the closed test section, and the wall is fabricated by the fiber fabric, both the characteristics of closed and open jet test section of conventional wind tunnel are combined in it. By thoroughly researching on the acoustics and aerodynamics of this acoustically transparent test section, significant progress in reducing the background noises in test section and improving the ratio of energy of the wind tunnel and some other aspects have been achieved. Acoustically transparent test section behaves better in acoustics and aerodynamics than conventional acoustic test section because of their high definition in detecting the sound sources and great performance in transmitting sounds.
基金supported by the Major Research Plan-Integrated Program of National Natural Science Foundation of China(No.92143301)the National Natural Science Foundation of China(No.31971318)Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Science(No.CIFMS 2019-I2M-5-018).
文摘Atmospheric particulate matter(PM)is a dominant source of air pollution,in particular,molecules less than 2.5μm in diameter,endangering human health.An estimated 2.1 million deaths from exposure to PM2.5 and 700,000 cases of respiratory disease caused by atmospheric pollution were reported on an annual basis.The main components of PM2.5 include heavy metal elements,water-soluble ions,carbon aerosols,ozone,and organic compounds.Per-and polyfluoroalkyl substances(PFASs)are a large group of representative pollutants among the organic compounds absorbed in PM2.5.PFASs are widely used in industrial production and hardly degraded in the environment,resulting in their accumulation in water,food,and air,and abosorbed by humans via ingestion and inhalation.On the other hand,accumulation of PFAS in the human body is proving to be associated with some unfavorable health outcomes,whereas the mechanisms underlying the effects of PFAS exposure on human lung diseases remain unclear at present.The toxicological effects of organic components are a significant focus of research.This review will fix our attention on the changes in the distribution,composition,and content of PFAS in PM2.5 by location and year,and provide an overview on the influence of PM2.5 and PFAS on lung health,with indications of possible synergistic adverse effects of PM2.5 and PFAS on pulmonary homeostasis.