The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and...The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and number concentration and median particle diameter of PM10 and PM2.5 as well as their correlation with relative humidity were analyzed. The results showed that the three indicators of PM10 and PM2.5 except for the mass concentration correlated with relative humidity,of which the correlation between the mass median particle diameter and relative humidity was the best. The correlation coefficient R^2 between the mass median particle diameter of PM10（ PM2.5） and relative humidity was up to 0. 943（ 0. 832）. Therefore,relative humidity and pressure are key impact factors of indicators of particles.展开更多
Airborne inhalable particles are a potent environmental pollutant. Formed via industrial processes, separation of these particles is difficult using conventional clean up techniques. In this work, solid nuclei particl...Airborne inhalable particles are a potent environmental pollutant. Formed via industrial processes, separation of these particles is difficult using conventional clean up techniques. In this work, solid nuclei particles of different chemical compositions were introduced into an agglomeration chamber with simulated flue gases to investigate their ability to remove these particles. Organic nuclei were able to capture more inhalable particles from coal-derived fly ash than inorganic nuclei, though these proved more effective for the agglomeration of inhalable particles in refuse-derived fly ash. Increasing the diameter of the solid nuclei benefitted the agglomeration process for both types of ash. Varying the local humidity changed adhesion between the particles and encouraged them to aggregate. Increasing the relative humidity consistently increased particle agglomeration for the refuse-derived ash. For coal-derived fly ash, the removal efficiency increased initially with relative humidity but then further increases in humidity had no impact on the relatively high efficiencies. After agglomeration in an atmosphere of 62% relative humidity, the mean mass diameter of inhalable particles in the coal-derived fly ash increased from 3.3 to 9.2 μm. For refuse-derived fly ash, agglomeration caused the percentage of particles that were less than 2μm to decrease from 40% to 15%. After treatment at a relative humidity of 61%, the mean size of inhalable particles exceeded 10 μm.展开更多
Based on the method of energy principle, an analytical approach for computing the capillary force for sphere/sphere geometry is presented in this paper. In modeling the capillary force, we consider spheres with both e...Based on the method of energy principle, an analytical approach for computing the capillary force for sphere/sphere geometry is presented in this paper. In modeling the capillary force, we consider spheres with both equal and non-equal radii, for both symmetric and asymmetric configurations at liquid/solid interfaces. We use numerical analysis to investigate the validity and efficiency of the derived model. The effect of various parameters including humidity, distance between two spheres, radii of spheres and contact angles on the meniscus force are investigated. Finally the results obtained from the model are compared with experimental measurements, and the accuracy and precision of the presented approach is verified.展开更多
文摘The TSI-3321 APS was used to measure concentration of atmospheric particulates in Ranjiaba region of Yubei District in Chongqing City during March 21- 29,2014,and the temporal variations in the hourly average mass and number concentration and median particle diameter of PM10 and PM2.5 as well as their correlation with relative humidity were analyzed. The results showed that the three indicators of PM10 and PM2.5 except for the mass concentration correlated with relative humidity,of which the correlation between the mass median particle diameter and relative humidity was the best. The correlation coefficient R^2 between the mass median particle diameter of PM10（ PM2.5） and relative humidity was up to 0. 943（ 0. 832）. Therefore,relative humidity and pressure are key impact factors of indicators of particles.
基金The authors wish to acknowledge the financial supports from the National Natural Science Foundation of China （Contract No. 21206080） and from the Major Project of Shandong Province for Research and Development （Contract No. 2015GSF117026）.
文摘Airborne inhalable particles are a potent environmental pollutant. Formed via industrial processes, separation of these particles is difficult using conventional clean up techniques. In this work, solid nuclei particles of different chemical compositions were introduced into an agglomeration chamber with simulated flue gases to investigate their ability to remove these particles. Organic nuclei were able to capture more inhalable particles from coal-derived fly ash than inorganic nuclei, though these proved more effective for the agglomeration of inhalable particles in refuse-derived fly ash. Increasing the diameter of the solid nuclei benefitted the agglomeration process for both types of ash. Varying the local humidity changed adhesion between the particles and encouraged them to aggregate. Increasing the relative humidity consistently increased particle agglomeration for the refuse-derived ash. For coal-derived fly ash, the removal efficiency increased initially with relative humidity but then further increases in humidity had no impact on the relatively high efficiencies. After agglomeration in an atmosphere of 62% relative humidity, the mean mass diameter of inhalable particles in the coal-derived fly ash increased from 3.3 to 9.2 μm. For refuse-derived fly ash, agglomeration caused the percentage of particles that were less than 2μm to decrease from 40% to 15%. After treatment at a relative humidity of 61%, the mean size of inhalable particles exceeded 10 μm.
文摘Based on the method of energy principle, an analytical approach for computing the capillary force for sphere/sphere geometry is presented in this paper. In modeling the capillary force, we consider spheres with both equal and non-equal radii, for both symmetric and asymmetric configurations at liquid/solid interfaces. We use numerical analysis to investigate the validity and efficiency of the derived model. The effect of various parameters including humidity, distance between two spheres, radii of spheres and contact angles on the meniscus force are investigated. Finally the results obtained from the model are compared with experimental measurements, and the accuracy and precision of the presented approach is verified.
