The study was undertaken to assess the extent of mercury contamination in the soil and three types of leaf plants in Campus AL-Mustansaryah University sites within Baghdad, Iraq, as well as to determine the relationsh...The study was undertaken to assess the extent of mercury contamination in the soil and three types of leaf plants in Campus AL-Mustansaryah University sites within Baghdad, Iraq, as well as to determine the relationship between environmental parameters and the distribution of the mercury contamination with carbon in soil samples were collected and analyzed for inorganic mercury. The highest mercury concentrations were recorded at the sites located lowest cover the plant and close to the diesel-electric generators. Mercury concentrations in leaf plant Ziziphusspina-christi higher concentration than the rest type and soil were mostly higher mercury concentration. Also ratio of carbon to coincide with the increase in the concentration of mercury in the soil of the study areas. Mercury is more biologically because of his preference to bind with carbon. This research confirms that Campus University is key areas for formation of bioavailable mercury distribution is tied to organic carbon.展开更多
Underground contamination by non-aqueous phase liquids (NAPLs) becomes increasingly serious. Rapid and reliable detection of contaminated zone and degree is the first step to site remediation. In this paper, diesel an...Underground contamination by non-aqueous phase liquids (NAPLs) becomes increasingly serious. Rapid and reliable detection of contaminated zone and degree is the first step to site remediation. In this paper, diesel and fine sand are used as experiment materials to investigate the applicability of using time-domain reflectometry (TDR) to detect LNAPLs contamination. The major work includes: measurement of dielectric constant and electrical conductivity for the diesel-water-air-sand mixtures; measurement of reflection waveform and dielectric constant for specimens with a diesel contaminated layer being sandwiched in sand. The experimental results show the followings: A significant decrease in both dielectric constant and electrical conductivity is observed for the diesel-water-air-sand mixtures when diesel displaces the pore water, and the content of diesel can be calculated by the model; insignificant change in dielectric properties is measured when diesel only displaces the pore gas; when the diesel contaminated sand is sandwiched between two saturated sand layers, the interfaces of the diesel contaminated layer can be identified by analyzing the reflection waveform; for field application, TDR method is valid for the case that LNAPLs seep into saturated sand layer, and the applicability of TDR method in vadose zone depends on the initial saturation of the sand layer. The findings obtained in this paper provide a guidance for the use of TDR for the field investigation of NAPLs contaminated site.展开更多
文摘The study was undertaken to assess the extent of mercury contamination in the soil and three types of leaf plants in Campus AL-Mustansaryah University sites within Baghdad, Iraq, as well as to determine the relationship between environmental parameters and the distribution of the mercury contamination with carbon in soil samples were collected and analyzed for inorganic mercury. The highest mercury concentrations were recorded at the sites located lowest cover the plant and close to the diesel-electric generators. Mercury concentrations in leaf plant Ziziphusspina-christi higher concentration than the rest type and soil were mostly higher mercury concentration. Also ratio of carbon to coincide with the increase in the concentration of mercury in the soil of the study areas. Mercury is more biologically because of his preference to bind with carbon. This research confirms that Campus University is key areas for formation of bioavailable mercury distribution is tied to organic carbon.
基金supported by the National High Technology Research and Development Program of China ("863" Project) (Grant No.2012AA062601)the National Natural Science Foundation of Major International Cooperation Projects (Grant No. 51010008)
文摘Underground contamination by non-aqueous phase liquids (NAPLs) becomes increasingly serious. Rapid and reliable detection of contaminated zone and degree is the first step to site remediation. In this paper, diesel and fine sand are used as experiment materials to investigate the applicability of using time-domain reflectometry (TDR) to detect LNAPLs contamination. The major work includes: measurement of dielectric constant and electrical conductivity for the diesel-water-air-sand mixtures; measurement of reflection waveform and dielectric constant for specimens with a diesel contaminated layer being sandwiched in sand. The experimental results show the followings: A significant decrease in both dielectric constant and electrical conductivity is observed for the diesel-water-air-sand mixtures when diesel displaces the pore water, and the content of diesel can be calculated by the model; insignificant change in dielectric properties is measured when diesel only displaces the pore gas; when the diesel contaminated sand is sandwiched between two saturated sand layers, the interfaces of the diesel contaminated layer can be identified by analyzing the reflection waveform; for field application, TDR method is valid for the case that LNAPLs seep into saturated sand layer, and the applicability of TDR method in vadose zone depends on the initial saturation of the sand layer. The findings obtained in this paper provide a guidance for the use of TDR for the field investigation of NAPLs contaminated site.
