10 research outputs found
Key factors impacting performance of a salinity gradient solar pond exposed to Mediterranean climate
Solar ponds are low cost pools of brine solutions with integrated storage zones that harvest incident solar energy and store it as thermal energy. The current study examined the performance of a salinity gradient solar pond under the Mediterranean climatic condition for ten consecutive months of operation, from October 8, 2014 to July 31, 2015. The presented results are based on the experimental data of a small-scale circular pond, 61�cm in diameter a height of 55�cm, constructed and operated at Middle East Technical University, Northern Cyprus Campus (METUNCC). The study showed the necessity of regular surface washing and having excess undissolved salt at the lower convective zone (LCZ) to maintain the pond stability. The variations in the temperature of the non-convective (NCZ) and lower convective zones (LCZ) are found to be a function of both ambient temperature and solar irradiation (insolation). The variation of the overall pond's temperature strongly follows the changes in ambient temperature while solar insolation directly affects the increase in temperature gradient by depth. During the period of this study, the pond reached the highest average temperature of 48��C in July 2015 while the average ambient temperature for this month was 30��C. � 2016 Elsevier Lt
Suspended fine particulate matter (PM2.5), microplastics (MPs), and polycyclic aromatic hydrocarbons (PAHs) in air: Their possible relationships and health implications
Exposure to fine particulate matter (PM2.5) and their associated microcontaminants have been linked to increased harmful effects on the human health. In this study, the possible relationships between PM2.5, microplastics (MPs), and polycyclic aromatic hydrocarbons (PAHs) were analyzed in an urban area of Bushehr port, in the northern part of the Persian Gulf. Presence, sources, and health risks of MPs and PAHs in both normal and dusty days were also investigated. The median of PM2.5 and ƩPAHs were 52.8 μg/m3 and 14.1 ng/m3, respectively, indicating high pollution levels especially in dusty days. The mean level of MPs in urban suspended PM2.5 was 5.2 items/m3. Fragments were the most abundant shape of identified MPs and polyethylene terephthalate (PET) was the most plastic types in urban dust of Bushehr port. The results revealed that PM2.5 and MPs may possibly act as a carrier for airborne MPs and PAHs, respectively. In addition, the significant positive relationships between MPs, wind speed and wind direction, confirmed that the MPs transportation were highly controlled by atmospheric condition. Moreover, the source identification methods and trajectory analyses indicated that petrogenic sources from both proximal and distal origins play an important role in the level of PAHs. The results of chronic health risk evaluation via inhalation revealed that PM2.5-bound PAHs had high potential cancer risk in winter, while, the estimated risks for non-carcinogenic PAHs were not considerable. In the case of MPs, the assessment of human intake of MPs via inhalation highlighted the possible risks for habitants
Quantifying trace elements in the emitted particulate matter during cooking and health risk assessment
Particulate matter (PM) measurements were conducted during heating corn oil, heating corn oil mixed with the table salt and heating low fat ground beef meat using a PTFE-coated aluminum pan on an electric stove with low ventilation. The main objectives of this study were to measure the size segregated mass concentrations, emission rates, and fluxes of 24 trace elements emitted during heating cooking oil or oil with salt and cooking meat. Health risk assessments were performed based on the resulting exposure to trace elements from such cooking activities. The most abundant elements (significantly different from zero) were Ba (24.4 ug m(-3)) during grilling meat and Ti during heating oil with salt (24.4 ug m(-3)). The health assessment indicates that the cooking with an electric stove with poor ventilation leading to chronic exposures may pose the risk of significant adverse health effects. Carcinogenic risk exceeded the acceptable level (target cancer risk 1 x 10(-6), US EPA 2015) by four orders of magnitude, while non-carcinogenic risk exceeded the safe level (target HQ = 1, US EPA 2015) by a factor of 5-20. Cr and Co were the primary contributors to the highest carcinogenic and non-carcinogenic risks, respectively
A new exposure route to trace elements in indoor particulate matter.
Concentrations and emission rates of sixteen trace elements in emitted PM during heating soybean oil using three types of pans, including Teflon, granitium, and cast-iron, were investigated. Statistically significant decreases in Mn and Co emission rates were observed when the oil was heated in the cast-iron pan compared to Teflon and granitium pans. Among the released trace elements, Ni, Ba, Zn, and Cr had more contribution to the emission rate. The concentrations of Fe in the emitted PM1 were found to be higher when cast-iron pan (8.49 +/- 3.35 mu g/m(3)) was utilized compared to Teflon (8.05 +/- 2.27 mu g/m(3)) and granitium (7.45 +/- 1.38 mu g/m(3)). However, these increases were statistically insignificant. The results of our study support the hypothesis that the trace elements translocate from cooking pans into the heated oil and subsequently to the particulate phase. This translocation creates a new inhalation exposure route to trace elements in indoor environments
The state of science on severe air pollution episodes : quantitative and qualitative analysis
202207 bckwVersion of RecordOthersNational Key R&D Program of ChinaPublishe