The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons（PAH） bound to submicrometer particles（particulate matter, PM1） suspended in the air of universi...The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons（PAH） bound to submicrometer particles（particulate matter, PM1） suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland,and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM1-bound PAH, the ratio（I/O） of the indoor to outdoor 24-hr concentrations of PM1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH（ΣPAH） to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated,in Warsaw – they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions.展开更多
The micro-Raman method is a non-contact and non-destructive method for thermal conductivity measurement.To reduce the measurement error induced by the poor fit of the basic equation of the original micro-Raman method,...The micro-Raman method is a non-contact and non-destructive method for thermal conductivity measurement.To reduce the measurement error induced by the poor fit of the basic equation of the original micro-Raman method,we developed a new basic equation for the heat source of a Gaussian laser beam.Based on the new basic equation,an analytical heat transfer model has been built to extend the original micro-Raman method to thin films with submicrometer-or nanometer-scale thickness.Ex-periments were performed to measure the thermal conductivity of dielectric thin films with submicrometer-or nanometer-scale thickness.The thermal resistance of the interface between dielectric thin films and their silicon substrate was also obtained.The obtained thermal conductivity of silicon dioxide film is 1.23W/(m.K),and the interface thermal resistance between silicon dioxide film and substrate is 2.35×10-8m2.K/W.The thermal conductivity and interface thermal resistance of silicon nitride film are 1.07W/(m.K)and 3.69×10-8m2.K/W,respectively.The experimental results are consistent with reported data.展开更多
The red phosphor materials CaS∶Cu+,Eu 2+ were firstly synthesized in a microwave field, and characterized by XRD、SEM、fluorescent spectroscopy. The experimental results of XRD and SEM show that the phosphors of CaS...The red phosphor materials CaS∶Cu+,Eu 2+ were firstly synthesized in a microwave field, and characterized by XRD、SEM、fluorescent spectroscopy. The experimental results of XRD and SEM show that the phosphors of CaS∶Cu+,Eu 2+ possess a spherical crystallite structure, in the submicrometer(250～500 nm) size range. Compared to the conventional high temperature solid state reaction this new synthetic technique exhibits interesting features, such as rapid reactions without other protective atmosphere,phosphors with high purity, smaller particles,and higher efficient luminescence.展开更多
基金financed from the funds of the WULS project No.505-10-052600-N00411-99(Principal Investigator:Karolina Kociszewska)the funds of the National Science Centre project No.DEC-2013/09/N/ST10/04224(Principal Investigator:Patrycja Rogula-Kopiec)
文摘The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons（PAH） bound to submicrometer particles（particulate matter, PM1） suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland,and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM1-bound PAH, the ratio（I/O） of the indoor to outdoor 24-hr concentrations of PM1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH（ΣPAH） to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated,in Warsaw – they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions.
基金supported by the State Key Program of National Natural Science Foundation of China(No. 50335010)the Zhejiang Provincial Natural Science Foundation(No.R105008),China
文摘The micro-Raman method is a non-contact and non-destructive method for thermal conductivity measurement.To reduce the measurement error induced by the poor fit of the basic equation of the original micro-Raman method,we developed a new basic equation for the heat source of a Gaussian laser beam.Based on the new basic equation,an analytical heat transfer model has been built to extend the original micro-Raman method to thin films with submicrometer-or nanometer-scale thickness.Ex-periments were performed to measure the thermal conductivity of dielectric thin films with submicrometer-or nanometer-scale thickness.The thermal resistance of the interface between dielectric thin films and their silicon substrate was also obtained.The obtained thermal conductivity of silicon dioxide film is 1.23W/(m.K),and the interface thermal resistance between silicon dioxide film and substrate is 2.35×10-8m2.K/W.The thermal conductivity and interface thermal resistance of silicon nitride film are 1.07W/(m.K)and 3.69×10-8m2.K/W,respectively.The experimental results are consistent with reported data.
文摘The red phosphor materials CaS∶Cu+,Eu 2+ were firstly synthesized in a microwave field, and characterized by XRD、SEM、fluorescent spectroscopy. The experimental results of XRD and SEM show that the phosphors of CaS∶Cu+,Eu 2+ possess a spherical crystallite structure, in the submicrometer(250～500 nm) size range. Compared to the conventional high temperature solid state reaction this new synthetic technique exhibits interesting features, such as rapid reactions without other protective atmosphere,phosphors with high purity, smaller particles,and higher efficient luminescence.
