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Chemical speciation of aerosols and air quality degradation during the festival of lights (Diwali)
2016
Pervez, Shamsh | Chakrabarty, Rajan K. | Dewangan, Shippi | Watson, John G. | Chow, Judith C. | Matawle, Jeevan Lal
Ambient PM2.5 (particulate matter less than 2.5 μm) samples, collected in a 8-week wintertime sampling program in two residential sites of Bhilai, India during the Indian Diwali festival in November 2012, were chemically characterized for 38 chemical species including eight speciated carbonaceous fractions (SCFs) of elemental (EC) and organic carbon (OC), twenty one metallic elements, and nine water soluble ionic species. Our objectives were to investigate: 1) relative abundances of SCFs contained in PM2.5during the Diwali festival period compared to normal days, and 2) enrichment pattern of potential inorganic markers of firework emission in ambient PM2.5during the festival days. Eight-fold increase inPM2.5mass concentrations were measured during the Diwali festival days compared to concentrations occurring in normal days. Bursting of firecrackers in the residential streets have shown significant contribution to the emission markers (K, Mg, Zn, S, EC and OC) along with crustal markers (Ca, Fe, Al) in ambient PM2.5aerosol samples. Concentrations of water soluble ionic species were found to be 10 times greater than those found in normal days. Further, the anion/cation ratios were found to reach a factor of 2; indicating the acidic character of emissions resulting from fireworks. The relative abundance of SCFs and higher ratios of OC to EC during the Diwali episode suggested the significant formation of secondary organic carbon (SOC) aerosols. We estimate that aerosols emitted from firework bursting contribute up to 32% of total ambient PM2.5 during the Diwali festival.
显示更多 [+] 显示较少 [-]Numerical simulations of river discharges, nutrient flux and nutrient dispersal in Jakarta Bay, Indonesia
2016
van der Wulp, Simon A. | Damar, Ario | Ladwig, Norbert | Hesse, Karl-J.
The present application of numerical modelling techniques provides an overview of river discharges, nutrient flux and nutrient dispersal in Jakarta Bay. A hydrological model simulated river discharges with a total of 90 to 377m3s−1 entering Jakarta Bay. Daily total nitrogen and total phosphorus loads ranged from 40 to 174tons and 14 to 60tons, respectively. Flow model results indicate that nutrient gradients are subject to turbulent mixing by tides and advective transport through circulation driven by wind, barotropic and baroclinic pressure gradients. The bulk of nutrient loads originate from the Citarum and Cisadane rivers flowing through predominantly rural areas. Despite lower nutrient loads, river discharges from the urban area of Jakarta exhibit the highest impact of nutrient concentrations in the near shore area of Jakarta Bay and show that nutrient concentrations were not only regulated by nutrient loads but were strongly regulated by initial river concentrations and local flow characteristics.
显示更多 [+] 显示较少 [-]Evaluation of anthropogenic contamination using sterol markers in a tropical estuarine system of northeast Brazil
2016
Frena, Morgana | Souza, Michel R.R. | Damasceno, Flaviana C. | Madureira, Luiz A.S. | Alexandre, Marcelo R.
The São Francisco River estuarine system, located in the Northeast coast of Brazil, has great economic, tourist and social importance. Its waters are used for activities such as agriculture, aquaculture, navigation and fishery, which supplies the surrounding communities. In this study, sterols markers were determined in twenty-eight sediment samples from São Francisco River estuary by gas chromatography - mass spectrometry (GC–MS). Sterol analysis was useful to distinguish between anthropogenic and biogenic organic matter (OM) sources in the studied area. Six sterols were quantified, suggesting different sources. Concentrations of fecal sterol (coprostanol) were lower than 500ngg−1, suggesting no indicative of severe sewage contamination.However, two stations showed concentrations around 100ngg−1 and the values for the coprostanol/(coprostanol+cholestanol) and coprostanol/cholesterol ratios indicates sewage contamination. The results in this study may be considered as baseline concentrations to be used as future reference for monitoring programs to prevent anthropogenic impacts.
显示更多 [+] 显示较少 [-]Assessment of concentration, bioaccumulation and sources of polycyclic aromatic hydrocarbons in zooplankton of Chabahar Bay
2016
Ziyaadini, Morteza | Mehdinia, Ali | Khaleghi, Leila | Nassiri, Mahmoud
The amounts and sources of polycyclic aromatic hydrocarbons (PAHs) and their bioaccumulation factors (BAFs) in the zooplankton community of Chabahar Bay were investigated. The highest amounts of total PAHs (tPAHs) in the water and zooplankton samples were 62.2ngL−1 and 1478.6ngg−1 dry weights, in near the Shahid Beheshti Port and desalination, respectively. The greatest amount of BAF (51,780) was obtained in the entry of Bay, and it was related to the phenanthrene accumulation. Using molecular ratio, the results showed that the major input source of PAH compounds in zooplankton of Chabahar Bay was pyrolytic (fuel) source.
显示更多 [+] 显示较少 [-]Bioaccumulation of heavy metals in marine organisms and sediments from Admiralty Bay, King George Island, Antarctica
2016
Trevizani, Tailisi Hoppe | Figueira, Rubens Cesar Lopes | Ribeiro, Andreza Portella | Theophilo, Carolina Yume Sawamura | Majer, Alessandra Pereira | Petti, Mônica Angélica Varella | Corbisier, Thais Navajas | Montone, Rosalinda Carmela
The Antarctic continent is considered a low-impact environment; however, there is a tendency to increase the contaminants' levels due to human activities in the research stations. In this study, As, Cd, Cr, Cu, Hg, Ni, Pb and Zn levels in sediment and biota were determined in the environmental samples from Admiralty Bay (King George Island, Antarctica) collected in 2003. The results demonstrated high concentrations of Cu and Zn in the sediments. There was bioaccumulation of As in the biota from Admiralty Bay and bioaccumulation of Zn specifically in the biota from Martel Inlet. In addition, the results were useful in order to understand the heavy metal levels for the pre-accident condition of Comandante Ferraz Antarctic Station, where an accident occurred in 2012, and also for the comparison with current conditions within the monitoring work developed by INCT-APA (National Institute of Science and Technology for Environmental Research Antarctic).
显示更多 [+] 显示较少 [-]Modeling and optimization of Newfoundland shrimp waste hydrolysis for microbial growth using response surface methodology and artificial neural networks
2016
Zhang, Kedong | Zhang, Baiyu | Chen, Bing | Jing, Liang | Zhu, Zhiwen | Kazemi, Khoshrooz
The hydrolyzed protein derived from seafood waste is regarded as a premium and low-cost nitrogen source for microbial growth. In this study, optimization of enzymatic shrimp waste hydrolyzing process was investigated. The degree of hydrolysis (DH) with four processing variables including enzyme/substrate ratio (E/S), hydrolysis time, initial pH value and temperature, were monitored. The DH values were used for response surface methodology (RSM) optimization through central composite design (CCD) and for training artificial neural network (ANN) to make a process prediction. Results indicated that the optimum levels of variables are: E/S ratio at 1.64%, hydrolysis time at 3.59h, initial pH at 9 and temperature at 52.57°C. Hydrocarbon-degrading bacteria Bacillus subtilis N3-1P was cultivated using different DHs of hydrolysate. The associated growth curves were generated. The research output facilitated effective shrimp waste utilization.
显示更多 [+] 显示较少 [-]Total petroleum hydrocarbon degradation by hybrid electrobiochemical reactor in oilfield produced water
2016
Mousa, Ibrahim E.
The crude oil drilling and extraction operations are aimed to maximize the production may be counterbalanced by the huge production of contaminated produced water (PW). PW is conventionally treated through different physical, chemical, and biological technologies. The efficiency of suggested hybrid electrobiochemical (EBC) methods for the simultaneous removal of total petroleum hydrocarbon (TPH) and sulfate from PW generated by petroleum industry is studied. Also, the factors that affect the stability of PW quality are investigated. The results indicated that the effect of biological treatment is very important to keep control of the electrochemical by-products and more TPH removal in the EBC system. The maximum TPH and sulfate removal efficiency was achieved 75% and 25.3%, respectively when the detention time was about 5.1min and the energy consumption was 32.6mA/cm2. However, a slight increasing in total bacterial count was observed when the EBC compact unit worked at a flow rate of average 20L/h. Pseudo steady state was achieved after 30min of current application in the solution. Also, the results of the study indicate that when the current intensity was increased above optimum level, no significant results occurred due to the release of gases.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons (PAHs) in water from three estuaries of China: Distribution, seasonal variations and ecological risk assessment
2016
Yan, Jinxia | Liu, Jingling | Shi, Xuan | You, Xiaoguang | Cao, Zhiguo
The distribution, seasonal variations and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in water from three estuaries in Hai River Basin of China, which has been suffering from different anthropogenic pressures, were investigated. In three estuaries, the average concentration of ΣPAHs was the lowest in Luan River estuary, followed by Hai River estuary, and the highest in Zhangweixin River estuary. There were significant seasonal variations in ΣPAHs, the concentrations of ΣPAHs were higher in November than in May and August. The composition profiles of PAHs in different sites were significantly different, and illustrated seasonal variations. Generally, 2-ring (Nap) and 3-ring PAHs (Acp, Fl and Phe) were the most abundant components at most sampling sites in three estuaries. The PAHs in three estuaries were mainly originated from pyrogenic sources. A method based on toxic equivalency factors (TEFs) and risk quotient (RQ) was proposed to assess the ecological risk of ΣPAHs, with the ecological risk of individual PAHs being considered separately. The results showed that the ecological risks caused by ΣPAHs were high in Hai River estuary and Zhangweixin River estuary, and moderate in Luan River estuary. The mean values of ecological risk in August were lower than those in November. The contributions of individual PAHs to ecological risk were different in May, August and November. 3-ring and 4-ring PAHs accounted for much more ecological risk than 2-ring, 5-ring and 6-ring, although the contributions of 5-ring and 6-ring to ecological risk were higher than these to PAHs concentrations.
显示更多 [+] 显示较少 [-]Assessment of polycyclic aromatic hydrocarbons (PAHs) in mussels (Mytilus galloprovincialis) of Prince Islands, Marmara Sea
2016
Balcıoğlu, Esra Billur
In this study, PAH analyses have been conducted on indigenous mussels. Mussel samples (Mytilus galloprovincialis) have been collected from seven stations of Prince Islands during September 2015. Concentrations of total determined PAHs (sum of 16 compounds) ranged between 664 and 9083ngg−1. The origin of PAHs has been found to be pyrolytic according to the PHE/ANT and FA/PYR ratios in Büyükada. For other islands, PAH origins have been observed as pyrolytic and petrogenic together according to the PHE/ANT, FA/PYR and BaA/CHR ratios.
显示更多 [+] 显示较少 [-]Green Marine: An environmental program to establish sustainability in marine transportation
2016
Walker, Tony R.
European maritime companies have adopted programs to limit operational impacts on the environment. For maritime companies in North America, the Green Marine Environmental Program (GMEP) offers a framework to establish and reduce environmental footprints. Green Marine (GM) participants demonstrate annual improvements of specific environmental performance indicators (e.g., reductions in air pollution emissions) to maintain certification. Participants complete annual self-evaluations with results determining rankings for performance indicators on a 1-to-5 scale. Self-evaluations are independently verified every two years to ensure rigor and individual results are made publicly available annually to achieve transparency. GM benefits the marine industry across North America by encouraging sustainable development initiatives. GM's credibility is reflected through a diverse network of environmental groups and government agencies that endorse and help shape the program. Merits of this relatively new maritime certification (not previously described in the academic literature), are discussed.
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