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Distribution of heavy metals around the Barakah nuclear power plant in the United Arab Emirates Texto completo
2017
Al Rashdi, MouzaRashid | Alaabed, Sulaiman | El Tokhi, Mohamed | Howari, FaresM. | El Mowafi, Walid | Arabi, AlyaA.
Distribution of heavy metals around the Barakah nuclear power plant in the United Arab Emirates Texto completo
2017
Al Rashdi, MouzaRashid | Alaabed, Sulaiman | El Tokhi, Mohamed | Howari, FaresM. | El Mowafi, Walid | Arabi, AlyaA.
Inductively coupled plasma emission spectroscopy was used to measure the concentrations of heavy metals in 58 samples collected from the Barakah nuclear power plant (BNPP) area, UAE. The grain size distribution was symmetric, but the samples ranged from fine to coarse sand. The inverse relationship between grain size and heavy metal contaminations was validated. The pre-operational average heavy metal contaminations around the BNPP were 0.03, 0.40, 1.2, 2.05, 1.66, 1.6, 5.9, 7.3, 7, 8.8, 60, and 2521 ppm for Cd, Mo, Co, Cu, Pb, As, Zn, Ni, V, Cr, Mn, and Fe, respectively. The spatial distribution was more compact in the south compared to the north, with less severe contaminations in the east and west. The negative geoaccumulation indices suggest an uncontaminated area, and the BNPP has minor enrichments. All concentrations were significantly below the safe limits set by the Dutch guidelines. The levels of heavy metals reported in the UAE were lower than levels reported in countries around the world.
Mostrar más [+] Menos [-]Distribution of heavy metals around the Barakah nuclear power plant in the United Arab Emirates Texto completo
Al Rashdi, Mouza Rashid | Alaabed, Sulaiman | El Tokhi, Mohamed | Howari, Fares M. | El Mowafi, Walid | Arabi, Alya A.
© 2017, Springer-Verlag Berlin Heidelberg. Inductively coupled plasma emission spectroscopy was used to measure the concentrations of heavy metals in 58 samples collected from the Barakah nuclear power plant (BNPP) area, UAE. The grain size distribution was symmetric, but the samples ranged from fine to coarse sand. The inverse relationship between grain size and heavy metal contaminations was validated. The pre-operational average heavy metal contaminations around the BNPP were 0.03, 0.40, 1.2, 2.05, 1.66, 1.6, 5.9, 7.3, 7, 8.8, 60, and 2521 ppm for Cd, Mo, Co, Cu, Pb, As, Zn, Ni, V, Cr, Mn, and Fe, respectively. The spatial distribution was more compact in the south compared to the north, with less severe contaminations in the east and west. The negative geoaccumulation indices suggest an uncontaminated area, and the BNPP has minor enrichments. All concentrations were significantly below the safe limits set by the Dutch guidelines. The levels of heavy metals reported in the UAE were lower than levels reported in countries around the world.
Mostrar más [+] Menos [-]The effect of different surface materials on runoff quality in permeable pavement systems Texto completo
2017
Li, Haiyan | Li, Zhifei | Zhang, Xiaoran | Li, Zhuorong | Liu, Dongqing | Li, Tanghu | Zhang, Ziyang
To investigate the effect of different permeable pavement surface materials on the removal of pollutants from urban storm-runoff, six commonly surface materials (porous asphalt, porous concrete, cement brick, ceramic brick, sand base brick, and shale brick) were selected in this study and the research was carried out by column experiments. Except the concentrations of total suspended solids (TSS), chemical oxygen demand (COD), ammonia nitrogen (NH₄-N), nitrate nitrogen (NO₃-N), total nitrogen (TN), and total phosphorus (TP) in the influent and effluent that were measured, the removal mechanism of pollutants was discussed further. The results indicate that the surface materials influence the removal efficiency of pollutants greatly and have different effects on certain pollutant. Furthermore, the physical interception and adsorption would be the main mechanism for the removal of pollutants from runoff. For example, for all surface materials, the average removal efficiency of TSS is nearly about 90.0% because of physical interception. Due to the amount of iron oxide, the removal efficiency of COD, NO₃-N, and TN of shale brick was 88.2, 35.1, and 17.5%, respectively. NH₄-N and TN can be easily removed by porous asphalt due to the high content of organic matter. By lacking of useful adsorption sites, all the surface materials had little effect on the removal of TP from runoff. This research could offer useful guidelines for the better design of permeable pavement system and promote the insight into the removal mechanism of pollutants in permeable pavement system. Graphical abstract Different types of materials for the different types of pollutants in the runoff purification capacity were significantly different, overall, shale brick and porous asphalt Shale bricks and porous asphalt have a better purification effect according to the six kinds of materials
Mostrar más [+] Menos [-]Assessment of trace metal accumulation in native mussels (Brachidontes rodriguezii) from a South American temperate estuary Texto completo
2017
Buzzi, Natalia Sol | Oliva, Ana Laura | Arias, Andrés Hugo | Marcovecchio, Jorge Eduardo
Assessment of trace metal accumulation in native mussels (Brachidontes rodriguezii) from a South American temperate estuary Texto completo
2017
Buzzi, Natalia Sol | Oliva, Ana Laura | Arias, Andrés Hugo | Marcovecchio, Jorge Eduardo
The present work provides the first results in heavy metal bioaccumulation in the autochthonous mussel Brachidontes rodriguezii from the Bahía Blanca Estuary (Argentina), one of the most important coastal environments of South America, subjected to different anthropogenic pressure. The study is based on the detection of Cd, Cu, Pb, Mn, and Fe in mussels’ soft tissue and sediments’ fine fraction by means of inductively coupled plasma atomic emission spectroscopy (ICP-OES), in order to analyze the potential relationship between both components of the aquatic system. Additionally, different indices are calculated with the purpose of obtaining detailed data. The heavy metal burden in mussels varied seasonally, showing a clearer pattern for the stations located in the internal area of the estuary. Metals exhibited maximum values in summer and to a lesser extent in winter, followed by a decrease during spring. Multiple international guideline assessment allowed classifying the area as moderately polluted, including a low range for Cd and medium for Cu and Pb. Moreover, the average detected levels were within the measured ranges in other coastal areas. Regarding human health, trace metal content in mussels met the national and international standards for safe consumption.
Mostrar más [+] Menos [-]Assessment of trace metal accumulation in native mussels (Brachidontes rodriguezii) from a South American temperate estuary Texto completo
2017
Buzzi, Natalia Sol | Oliva, Ana Laura | Arias, Andres Hugo | Marcovecchio, Jorge Eduardo
The present work provides the first results in heavy metal bioaccumulation in t he autochthonous mussel Brachidontes rodriguezii from the Bahía Blanca Estuary (Argentina), one of the most important coastal environments of South America, subjected to different anthropogenic pressure. The study is based on the detection of Cd, Cu, Pb, Mn, and Fe in mussels ’ soft tissue and sediments ’ fine fraction by means of inductively coupled plasma atomic emission spec- troscopy (ICP-OES), in order to analyze the potential relation- ship between both components of the aquatic system. Additionally, different indices are calculated with the purpose of obtaining detailed data. The heavy metal burden in mussels varied seasonally, showing a clearer pattern for the stations located in the internal area of the estuary. Metals exhibited maximum values in summer and to a lesser extent in winter, followed by a decrease during spring. Multiple international guideline assessment allowed classifying the area as moder- ately polluted, including a low range for Cd and medium for Cu and Pb. Moreover, the average detected levels were within the measured ranges in other coastal areas. Regarding human health, trace metal content in mussels met the national and international standards for safe consumption. | Fil: Buzzi, Natalia Sol. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina | Fil: Oliva, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina | Fil: Arias, Andres Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur; Argentina | Fil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Tecnológica Nacional; Argentina. Universidad FASTA "Santo Tomas de Aquino"; Argentina
Mostrar más [+] Menos [-]A survey of mycotoxin contamination and chemical composition of distiller’s dried grains with solubles (DDGS) imported from the USA into Saudi Arabia Texto completo
2017
Abudabos, Alaeldein M. | Al-Atiyat, Raed M. | Khan, Rifat Ullah
Distiller’s dried grains with solubles (DDGS) is a source of nutritional feedstuff for poultry farmers and industry. The DDGS is a by-product of ethanol industry and an economical feed source of energy, amino acids, crude fiber, minerals, and vitamins. The use of DDGS as a feed ingredient is a novel idea and little information is available on its dietary composition. Many factors such as the type of plants, locality, year of production, and the conditions during distillation process affect the chemical composition of DDGS. In this paper, the chemical composition and the presence of mycotoxin in DDGS imported from the USA into Saudi Arabia as a feedstuff for poultry have been documented.
Mostrar más [+] Menos [-]Effect of organic manure on Cd and As accumulation in brown rice and grain yield in Cd-As-contaminated paddy fields Texto completo
2017
Xiao, Anwen | Ouyang, Yun | Li, Wai Chin | Ye, Zhihong
Large areas of paddy fields in mining areas in south China have been contaminated by mixed Cd and As. To test the possibility of using organic manure (OM) as a method of reducing Cd and As accumulation in brown rice and increase the grain yield in such paddy fields, two rice cultivars [Jianyou G2 (JY) and Fengyousimiao (FY)] and three amounts of OM (0, 0.5, 1.5 kg/m²) were examined in three Cd-As-contaminated paddy fields (Fogang, Dabaoshan, Fankou) in Guangdong Province. The results show that the application of OM can effectively increase the grain yield and reduce Cd. However, the As concentration was found to increase in brown rice, especially when high levels of OM were used. The addition of OM increased the soil pH and organic matter content in the soils and enhanced the activities of superoxide dismutase (SOD) and catalase (CAT) in plant tissues. Our results suggest that OM can be used as an amendment to effectively decrease Cd accumulation in brown rice in Cd-contaminated paddy fields. However, it is necessary to consider the negative effects of OM amendments when adding OM to As-contaminated paddy fields.
Mostrar más [+] Menos [-]Sources and fate of microplastics in marine and beach sediments of the Southern Baltic Sea—a preliminary study Texto completo
2017
Graca, Bożena | Szewc, Karolina | Zakrzewska, Danuta | Dołęga, Anna | Szczerbowska-Boruchowska, Magdalena
Microplastics’ (particles size ≤5 mm) sources and fate in marine bottom and beach sediments of the brackish are strongly polluted Baltic Sea have been investigated. Microplastics were extracted using sodium chloride (1.2 g cm⁻³). Their qualitative identification was conducted using micro-Fourier-transform infrared spectroscopy (μFT-IR). Concentration of microplastics varied from 25 particles kg⁻¹ d.w. at the open sea beach to 53 particles kg⁻¹ d.w. at beaches of strongly urbanized bay. In bottom sediments, microplastics concentration was visibly lower compared to beach sediments (0–27 particles kg⁻¹ d.w.) and decreased from the shore to the open, deep-sea regions. The most frequent microplastics dimensions ranged from 0.1 to 2.0 mm, and transparent fibers were predominant. Polyester, which is a popular fabrics component, was the most common type of microplastic in both marine bottom (50%) and beach sediments (27%). Additionally, poly(vinyl acetate) used in shipbuilding as well as poly(ethylene-propylene) used for packaging were numerous in marine bottom (25% of all polymers) and beach sediments (18% of all polymers). Polymer density seems to be an important factor influencing microplastics circulation. Low density plastic debris probably recirculates between beach sediments and seawater in a greater extent than higher density debris. Therefore, their deposition is potentially limited and physical degradation is favored. Consequently, low density microplastics concentration may be underestimated using current methods due to too small size of the debris. This influences also the findings of qualitative research of microplastics which provide the basis for conclusions about the sources of microplastics in the marine environment.
Mostrar más [+] Menos [-]Screening of inorganic and organic contaminants in floodwater in paddy fields of Hue and Thanh Hoa in Vietnam Texto completo
2017
Trinh, Ha Thu | Marcussen, Helle | Hansen, Hans Christian B. | Le, Giang Truong | Duong, Hanh Thi | Ta, Nguyen Thuy | Nguyen, Trung Quang | Hansen, Søren | Strobel, Bjarne W.
In the rainy season, rice growing areas in Vietnam often become flooded by up to 1.5 m water. The floodwater brings contaminants from cultivated areas, farms and villages to the rice fields resulting in widespread contamination. In 2012 and 2013, the inorganic and organic contaminants in floodwater was investigated in Thanh Hoa and Hue. Water samples were taken at 16 locations in canals, paddy fields and rivers before and during the flood. In total, 940 organic micro-pollutants in the water samples were determined simultaneously by GC-MS method with automatic identification and quantification system (AIQS), while ICP-MS was used for determination of ten trace elements in the samples. The concentrations of 277 organic micro-pollutants and ten elements (As, Cu, Cd, Cr, Co, Pb, Zn, Fe, Mn, Al) ranged from 0.01 to 7.6 μg L⁻¹ and 0.1 to 3170 μg L⁻¹, respectively, in the floodwater. Contaminants originated from industrial sources (e.g. PAH) were detected at low concentrations, ranged from 0.01 to 0.18 μg L⁻¹, while concentrations of pollutants originated from domestic sources (e.g. sterols, pharmaceuticals and personal care products and pesticides) were ranged from 0.01 to 2.12 μg L⁻¹. Isoprocarb had the highest detection frequency of 90%, followed by isoprothiolane (88%) and fenobucarb (71%). The results indicated that contaminants in floodwater come from untreated wastewater from villages, and the agricultural activities are the major sources of increased pesticides resuspended in the floodwater in this study.
Mostrar más [+] Menos [-]Evaluation of an activated carbon packed bed for the adsorption of phenols from petroleum refinery wastewater Texto completo
2017
El-Naas, Muftah H. | Alhaija, Manal A. | Al-Zuhair, Sulaiman
The performance of an adsorption column packed with granular activated carbon was evaluated for the removal of phenols from refinery wastewater. The effects of phenol feed concentration (80–182 mg/l), feed flow rate (5–20 ml/min), and activated carbon packing mass (5–15 g) on the breakthrough characteristics of the adsorption system were determined. The continuous adsorption process was simulated using batch data and the parameters for a new empirical model were determined. Different dynamic models such as Adams–Bohart, Wolborsko, Thomas, and Yoon-Nelson models were also fitted to the experimental data for the sake of comparison. The empirical, Yoon–Nelson and Thomas models showed a high degree of fitting at different operation conditions, with the empirical model giving the best fit based on the Akaike information criterion (AIC). At an initial phenol concentration of 175 mg/l, packing mass of 10 g, a flow rate of 10 ml/min and a temperature of 25 °C, the SSE of the new empirical and Thomas models were identical (248.35) and very close to that of the Yoon–Nelson model (259.49). The values were significantly lower than that of the Adams–Bohart model, which was determined to be 19,358.48. The superiority of the new empirical model and the Thomas model was also confirmed from the values of the R ² and AIC, which were 0.99 and 38.3, respectively, compared to 0.92 and 86.2 for Adams–Bohart model.
Mostrar más [+] Menos [-]Response to lead pollution: mycorrhizal Pinus sylvestris forms the biomineral pyromorphite in roots and needles Texto completo
2017
Bizo, Maria L. | Nietzsche, Sandor | Mansfeld, Ulrich | Langenhorst, Falko | Majzlan, Juraj | Göttlicher, Jörg | Ozunu, Alexandru | Formann, Steffi | Krause, Katrin | Kothe, Erika
The development of mycorrhized pine seedlings grown in the presence of lead was assessed in order to investigate how higher plants can tolerate lead pollution in the environment. Examination with scanning electron microscopy (SEM) revealed that Pb uptake was prominent in the roots, while a smaller amount was found in pine needles, which requires symplastic uptake and root-to-shoot transfer. Lead was concentrated in nanocrystalline aggregates attached to the cell wall and, according to elemental microanalyses, is associated with phosphorus and chlorine. The identification of the nanocrystalline phase in roots and needles was performed by transmission electron microscopy (TEM) and synchrotron X-ray micro-diffraction (μ-XRD), revealing the presence of pyromorphite, Pb₅[PO₄]₃(Cl, OH), in both roots and needles. The extracellular embedding of pyromorphite within plant cell walls, featuring an indented appearance of the cell wall due to a callus-like outcrop of minerals, suggests a biogenic origin. This biomineralization is interpreted as a defense mechanism of the plant against lead pollution.
Mostrar más [+] Menos [-]Bisection method for accurate modeling and simulation of fouling in hollow fiber membrane system Texto completo
2017
Liang, Shuang | Zhao, Yubo | Zhang, Jian | Song, Lianfa
Accurate description and modeling of fouling on hollow fibers imposes a serious challenge to more effective fouling mitigation and performance optimization of the membrane system. Although the governing equations for membrane fouling can be constructed based on the known theories from membrane filtration and fluid dynamics, they are unsolvable analytically due to the complex spatially and temporally varying nature of fouling on hollow fibers. The current available numerical solutions for the governing equations are either unreliable or inconvenient to use because of the uses of unfounded assumptions or cumbersome calculation methods. This work presented for the first time a rigorous numerical procedure to solve the governing equations for fouling development on hollow fibers. A critical step to achieve the goal is the use of bisection method to determine the transmembrane pressure at the dead end of the fibers. With this procedure, fouling behavior in the hollow fiber membrane system under a given condition can be simulated within a second. The model simulations were well calibrated and verified with the published experimental data from literature. Also presented in the paper were simulations for performances of the hollow fiber membrane system under various operation conditions. Graphical abstract ᅟ
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