ABSTRACT
In this research, 29 surface sediments samples of three typical lake reservoirs (in Yuqiao Reservoir, Hengshui Lake, and Dahuofang Reservoir) in the Jin-Ji-Liao area were collected and investigated, and the contents of 16 polycyclic aromatic hydrocarbons were detected using GC-MS. The results show that the Sigma PAHs (ng·g-1) in the sediments were 337.3-1604.1 (mean value 820.0), 461.1-1497.5 (mean value 932.3), and 102.3-2240.5 (mean value 564.9), respectively. Compared with other domestic rivers and lakes, the pollution levels of the PAHs in the three typical lakes were all at a medium level. The three lakes and reservoirs had consistency in the ratio of the number of rings, which is primarily high. PAHs source analyses were carried out by the characteristic ratio and primary component analysis method, and the results show that three lakes reservoirs pollution were caused mostly by combustion sources (including petroleum, coal, and biomass combustion), with a few petroleum sources. Additionally, the pollution contribution ratio of incomplete combustion of gasoline and diesel oil was 51.4%, and the pollution contribution ratio of combustion of coal and firewood were 22.3%. The risk evaluation results indicate that PAHs in the surface sediments of Yuqiao Reservoir, Hengshui Lake, and Dahuofang Reservoir are generally at a medium and low level, but the monitoring of three types of substances, Flu, InP, and DahA, should be strengthened, and corresponding emergency measures should be taken.
ABSTRACT
CdS nanoflake arrays (NFAs) exhibit unprecedented light absorption capability, and they can serve as a scaffold to load thin organic absorbers for extraordinarily high light absorption. As a result, the hybrid solar cell consisting of NFAs and organic absorber yields a ten-times high short-circuit photocurrent compared to the counterpart device with a common planar structure.
ABSTRACT
Fenton catalytic degradation of dimethyl sulfoxide (DMSO) by using liquid-phase pulsed high voltage discharge was carried out. The discharge was driven by a self-made pulsed power supply providing a pulse rising time of 400 ns, discharge repetition rate of 96.2 Hz, peak voltage of 20 kV. The side surface of discharge electrode was insulated in order to limit the discharge current, followed by estimating its effect on single pulse power. The effects of aqueous conductivity, Fe(II), and O2 flow rate on liquid-phase discharge induced DMSO degradation and aqueous conductivity on corresponding H2O2 yield were investigated. The concentrations and selectivities of intermediates of DMSO degradation, were also studied. The results indicated that when using the insulated electrode, single pulse power had a limiting value with increasing the aqueous conductivity; DMSO degradation rate was reduced with increasing the aqueous conductivity and O2 flow rate,whereas Fe(II) showed a Fenton catalytic oxidation of DMSO; 80% of DMSO degradation rate was achieved at the pulsed high voltage discharge time of 45 min and the resultant biodegradability was enhanced by at least 32%-48%; the maximum energy efficiency in G(37%) was 0.0087 mol/(kW x h). The study suggested that the liquid-phase plasma combined catalyst promised the potential of organic compound degradation.
