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Sample records for heavy water enrichment

  1. Comparing DNA enrichment of proliferating cells following administration of different stable isotopes of heavy water.

    Science.gov (United States)

    Farthing, Don E; Buxbaum, Nataliya P; Lucas, Philip J; Maglakelidze, Natella; Oliver, Brittany; Wang, Jiun; Hu, Kevin; Castro, Ehydel; Bare, Catherine V; Gress, Ronald E

    2017-06-22

    Deuterated water (2H2O) is a label commonly used for safe quantitative measurement of deuterium enrichment into DNA of proliferating cells. More recently, it has been used for labeling proteins and other biomolecules. Our in vitro - in vivo research reports important stable isotopic labeling enrichment differences into the DNA nucleosides and their isotopologues (e.g. deoxyadenosine (dA) M + 1, dA M + 2, dA M + 3), as well as tumor cell proliferation effects for various forms of commercially available stable heavy water (2H2O, H218O, and 2H218O). Using an in vitro mouse thymus tumor cell line, we determined that H218O provides superior DNA labeling enrichment quantitation, as measured by GC-positive chemical ionization (PCI)-MS/MS. In addition, at higher but physiologically relevant doses, both 2H218O and 2H2O down modulated mouse thymus tumor cell proliferation, whereas H218O water had no observable effects on cell proliferation. The in vivo labeling studies, where normal mouse bone marrow cells (i.e. high turnover) were evaluated post labeling, demonstrated DNA enrichments concordant with measurements from the in vitro studies. Our research also reports a headspace-GC-NCI-MS method, which rapidly and quantitatively measures stable heavy water levels in total body water.

  2. Production of heavy water

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Larry S.; Brown, Sam W.; Phillips, Michael R.

    2017-06-06

    Disclosed are methods and apparatuses for producing heavy water. In one embodiment, a catalyst is treated with high purity air or a mixture of gaseous nitrogen and oxygen with gaseous deuterium all together flowing over the catalyst to produce the heavy water. In an alternate embodiment, the deuterium is combusted to form the heavy water. In an alternate embodiment, gaseous deuterium and gaseous oxygen is flowed into a fuel cell to produce the heavy water. In various embodiments, the deuterium may be produced by a thermal decomposition and distillation process that involves heating solid lithium deuteride to form liquid lithium deuteride and then extracting the gaseous deuterium from the liquid lithium deuteride.

  3. On Heavy Element Enrichment in Classical Novae

    Science.gov (United States)

    Alexakis, A.; Calder, A. C.; Heger, A.; Brown, E. F.; Dursi, L. J.; Truran, J. W.; Rosner, R.; Lamb, D. Q.; Timmes, F. X.; Fryxell, B.; Zingale, M.; Ricker, P. M.; Olson, K.

    2004-02-01

    Many classical nova ejecta are enriched in CNO and Ne. Rosner and coworkers recently suggested that the enrichment might originate in the resonant interaction between large-scale shear flows in the accreted H/He envelope and gravity waves at the interface between the envelope and the underlying C/O white dwarf (WD). The shear flow amplifies the waves, which eventually form cusps and break. This wave breaking injects a spray of C/O into the superincumbent H/He. Using two-dimensional simulations, we formulate a quantitative expression for the amount of C/O per unit area that can be entrained, at saturation, into the H/He. The fraction of the envelope that is enriched depends on the horizontal distribution of shear velocity and the density contrast between the C/O WD and the H/He layer but is roughly independent of the vertical shape of the shear profile. Using this parameterization for the mixed mass, we then perform several one-dimensional Lagrangian calculations of an accreting WD envelope and consider two scenarios: that the wave breaking and mixing is driven by the convective flows and that the mixing occurs prior to the onset of convection. In the absence of enrichment prior to ignition, the base of the convective zone, as calculated from mixing-length theory with the Ledoux instability criterion, does not reach the C/O interface. As a result, there is no additional mixing, and the runaway is slow. In contrast, the formation of a mixed layer during the accretion of H/He, prior to ignition, causes a more violent runaway. The envelope can be enriched by <~25% of C/O by mass (consistent with that observed in some ejecta) for shear velocities, over the surface, with Mach numbers <~0.4.

  4. Heavy metal enrichment in the riparian sediments and soils of the Three Gorges Reservoir, China

    Directory of Open Access Journals (Sweden)

    Q. Tang

    2015-03-01

    Full Text Available The Three Gorges Reservoir encompasses a riparian zone with a vertical height of 30 m and a total area of 349 km2 that has been subjected to alternate inundation and exposure due to regular impoundment. Sedimentation on the riparian landforms constitutes an important pathway for riverine contaminant redistribution. In an attempt to understand heavy metal enrichment since water inundation, riparian sediments and soils were sampled along five transects in a typical riparian zone composed of cultivated bench terraces in the middle reaches. Heavy metals (Cr, Ni, Cu, Zn, As, Cd and Pb were determined to characterize the lateral distribution and vertical transfer ratio. The results indicated that all heavy metals were enriched to varying extents both in the riparian sediments and soils, compared with regional background contents in soils and the reference levels in sediments. However, heavy metal levels in the riparian sediments were generally higher than those in the riparian soils, while those in the upper riparian soils (0–5 cm were overall slightly higher than those in the lower riparian soils (5–10 cm. There was a decreasing trend of heavy metal contents with increasing elevation. The elevated levels of heavy metals in the riparian sediments may be attributed to sediment yields from upstream anthropogenic sources, especially during major rainstorms in the wet season when large loads of contaminated sediment may be produced from diffuse source areas. Heavy metals can also be adsorbed to pure sediment in the course of mobilization or after deposition. Considering that the riparian soils are local weathering products without mobilization, the enrichment of heavy metals may principally be ascribed to chemical adsorption from dissolved fractions or vertical transfer from overlaid sediments. Heavy metal enrichment may further be affected by the specific type of hydrologic regime such that relatively long flooding duration caused by water

  5. Effects of nitrogen enrichment on heavy metals content of cattle ...

    African Journals Online (AJOL)

    The research was carried out at John Ker Nigeria Organo-Mineral Company site at Ikot Ekpene, Akwa Ibom State, Nigeria, to investigate the effect of nitrogen enrichment on contents of heavy metals in cattle dung/poultry manure compost and the growth of maize. Cattle dung was mixed with poultry manure in the ratio of 3:1 ...

  6. The ecological risk assessment of heavy metals in the Kuihe River basin (Xuzhou section) and the characteristics of plant enrichment

    Science.gov (United States)

    Sun, Ling; Zheng, Lei

    2018-01-01

    In order to investigate Kuihe River basin of heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) pollution, the determination of the Kuihe River water body, the bottom of the river silt, riparian soil plants and heavy metal content of 9 kinds of riparian plants, investigate the pollution situation, so as to screen out the plants that has potential of enrichment and rehabilitation of heavy metal pollution. The results showed that Cd and Mn in the water body exceed bid; The pollution of Zn and Cu in the bottom mud is serious, potential ecological risk of heavy metals is Zn>Cu>Pb>Ni>Cd>As>Cr>Mn Riparian soil affected by sewage and overflow of sediment has significant positive correlation with soil heavy metals, among them, the Zn and Cu are heavy pollution; The selective absorption of heavy metals by 9 kinds of dominant plant leads to its bio concentration factor (BCF) of Cr and Pb on the low side, are all less than 1, from the translocation factor (TF), Setcreasea purpurea and Poa annua showed obvious roots type hoarding. Poa annua and Lycium chinense have a resistance on the absorption of heavy metals, Lythrum salicaria, Photinia serrulata and Broussonetia papyrifera have a unique advantage on enrichment of heavy metals, Broussonetia papyri era on a variety of strong ability of enrichment and transfer of heavy metals suggests that the woody plants in the vast application prospect in the field of rehabilitation technology of heavy metals.

  7. Synthesis of Neutron Enriched Heavy and Superheavy Nuclei

    Science.gov (United States)

    Zagrebaev, V. I.; Karpov, A. V.; Greiner, Walter

    2014-09-01

    Applicability of different nuclear reactions (fusion of stable and radioactive nuclei, multi-nucleon transfers and neutron capture) for the production of new neutron enriched heavy nuclei is discussed in the paper. For the first time, a narrow pathway is found to the middle of the island of stability owing to possible β+-decay of SH isotopes which can be formed in ordinary fusion reactions of stable nuclei. Neutron capture reactions can be also used for the production of the long-living neutron rich SH nuclei. Strong neutron fluxes might be provided by pulsed nuclear reactors and by multiple nuclear explosions in laboratory conditions and by supernova explosions in nature. Low-energy multinucleon transfer reactions with actinide beams and targets are of special interest for synthesis of new neutron enriched transfermium nuclei and not-yet-known nuclei around the closed neutron shell N = 126 having largest impact on astrophysical r process. The estimated cross sections for the production of these nuclei look very promising to plan such experiments at available accelerators. Several new test experiments of such kind are proposed to perform including those in which a role of the shell effects in low-energy reaction dynamics could be clarify much better.

  8. HEAVY WATER MODERATED NEUTRONIC REACTOR

    Science.gov (United States)

    Szilard, L.

    1958-04-29

    A nuclear reactor of the type which utilizes uranium fuel elements and a liquid coolant is described. The fuel elements are in the form of elongated tubes and are disposed within outer tubes extending through a tank containing heavy water, which acts as a moderator. The ends of the fuel tubes are connected by inlet and discharge headers, and liquid bismuth is circulated between the headers and through the fuel tubes for cooling. Helium is circulated through the annular space between the outer tubes in the tank and the fuel tubes to cool the water moderator to prevent boiling. The fuel tubes are covered with a steel lining, and suitable control means, heat exchange means, and pumping means for the coolants are provided to complete the reactor assembly.

  9. Regional ecotoxicological hazards associated with anthropogenic enrichment of heavy metals

    NARCIS (Netherlands)

    Spijker, J.H.; Mol, G.; Posthuma, L.

    2011-01-01

    Regional geochemical data of heavy metals are commonly used for environmental risk assessment and management. Often these data are based on so-called total concentrations, whereas the exposure to the mobile or reactive fraction of these elements finally determines whether the exposed ecosystem is at

  10. Water issues associated with heavy oil production.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Quinn, J. J.; Environmental Science Division

    2008-11-28

    Crude oil occurs in many different forms throughout the world. An important characteristic of crude oil that affects the ease with which it can be produced is its density and viscosity. Lighter crude oil typically can be produced more easily and at lower cost than heavier crude oil. Historically, much of the nation's oil supply came from domestic or international light or medium crude oil sources. California's extensive heavy oil production for more than a century is a notable exception. Oil and gas companies are actively looking toward heavier crude oil sources to help meet demands and to take advantage of large heavy oil reserves located in North and South America. Heavy oil includes very viscous oil resources like those found in some fields in California and Venezuela, oil shale, and tar sands (called oil sands in Canada). These are described in more detail in the next chapter. Water is integrally associated with conventional oil production. Produced water is the largest byproduct associated with oil production. The cost of managing large volumes of produced water is an important component of the overall cost of producing oil. Most mature oil fields rely on injected water to maintain formation pressure during production. The processes involved with heavy oil production often require external water supplies for steam generation, washing, and other steps. While some heavy oil processes generate produced water, others generate different types of industrial wastewater. Management and disposition of the wastewater presents challenges and costs for the operators. This report describes water requirements relating to heavy oil production and potential sources for that water. The report also describes how water is used and the resulting water quality impacts associated with heavy oil production.

  11. On-line/on-site analysis of heavy metals in water and soils by laser induced breakdown spectroscopy

    Science.gov (United States)

    Meng, Deshuo; Zhao, Nanjing; Wang, Yuanyuan; Ma, Mingjun; Fang, Li; Gu, Yanhong; Jia, Yao; Liu, Jianguo

    2017-11-01

    The enrichment method of heavy metal in water with graphite and aluminum electrode was studied, and combined with plasma restraint device for improving the sensitivity of detection and reducing the limit of detection (LOD) of elements. For aluminum electrode enrichment, the LODs of Cd, Pb and Ni can be as low as several ppb. For graphite enrichment, the measurement time can be less than 3 min. The results showed that the graphite enrichment and aluminum electrode enrichment method can effectively improve the LIBS detection ability. The graphite enrichment method combined with plasma spatial confinement is more suitable for on-line monitoring of industrial waste water, the aluminum electrode enrichment method can be used for trace heavy metal detection in water. A LIBS method and device for soil heavy metals analysis was also developed, and a mobile LIBS system was tested in outfield. The measurement results deduced from LIBS and ICP-MS had a good consistency. The results provided an important application support for rapid and on-site monitoring of heavy metals in soil. (Left: the mobile LIBS system for analysis of heavy metals in soils. Top right: the spatial confinement device. Bottom right: automatic graphite enrichment device for on0line analysis of heavy metals in water).

  12. ``Heavy-water Lattice and Heavy-Quark''

    Science.gov (United States)

    Maksoed, Ssi, Wh-

    Refer to Birgitt Roettger-Roessler: ``Feelings at the Margins'', 2014 retrieved the Vienna, 2006 UNIDO Research Programme: Combating Marginalization and Poverty through Industrial Development/COMPID. Also from Vienna, on Feb 18-22, 1963 reported Technical Report Series 20 about ``Heavy Water Lattice''. Failed to relates scale-invariant properties of public-Debt growth to convergence in perturbation theory, sought JH Field: ``Convergence & Gauge Dependence Properties:..''. Furthers, in GP Lepage: ``On the Viabilities of Lattice Perturbation Theory'', 1992 stated: ``in terms of physical quantities, like the heavy-quark potential, greatly enhanced the predictive power of lattice perturbation theory''. Acknowledgements to HE. Mr. H. TUK SETYOHADI, Jl. Sriwijaya Raya 3, South-Jakarta, INDONESIA.

  13. Heavy Metal Enrichment in laminated lake sediments from N-Germany and N-Poland: Geochemical background, enrichment history and land surface changes

    Science.gov (United States)

    Hoelzmann, Philipp; Brauer, Achim; Dräger, Nadine; Kienel, Ulrike; Obremska, Milena; Ott, Florian; Słowinski, Michał

    2017-04-01

    For three lake sediment records, situated in rural environments in NE-Germany (Lake Tiefer See) and N-Poland (Lake Czechowskie, Lake Głęboczek), we present a detailed heavy metal enrichment history with sub-decadal resolution for the last 200 years. We determine the local and specific geogenic background values on the base of heavy-metal analysis of pre-industrial sediments and different sediment types (e.g. calcareous gyttja, organic gyttja etc.). These results provide means to calculate and quantify anthropogenic heavy metal accumulations and enrichment factors as well as to define regional measures for a state of reference, reflecting natural conditions without human impact. All three lakes show a similar pattern of relatively low heavy metal concentrations and only Pb, Zn and Cd show a clear parallel pattern of enrichment starting around 1850. This heavy metal enrichment mainly results from atmospheric input due to increasing industrialization within the framework of the Industrial Revolution. Highest concentrations of Cd, Zn, and Pb occur around 1960 to 1980 and thereafter a clear pattern of declining anthropogenic input is registered. This data is supplemented by calculations of mass accumulation rates to determine heavy metal input to the lakes for the past 200 years. For Lake Czechowskie the heavy metal input to the lake is compared to an on average five year resolved pollen record that reflects changes in land use and vegetation.

  14. RESEARCH OF SYSTEMS FOR WATER OXYGEN ENRICHMENT ON FISH FARM

    Directory of Open Access Journals (Sweden)

    Adnan Jažić

    2013-01-01

    Full Text Available Research of systems for oxygen enrichment of the water on the fish farms was carried out at the salmon farm, providing information on the practical application of the devices for oxygen enrichment of the water (sprinkler given the fact the salmon farm in question constantly faces the problem of reduced water inflow and consequent reduced concentration of oxygen (O2 in water. The aforementioned could result in lowered economic profitability of the production as well as serious health problems of fish on the farms. The role of the devices for efficient oxygen enrichment of water within the systems for intensive fish farming is to control and maintain optimal concentration of oxygen as a precondition for quality production, improvement of health and quality of fish, and to allow fish breeding in the fish farms during the drought season, lowered water levels in waterbeds and reduced inflow. Key words : Rainbow trout, oxygen, water sprinkler

  15. Page 1 THE RAMAN SPECTRA OF WATER, HEAVY WATER AND ...

    Indian Academy of Sciences (India)

    THE Raman spectra of water, heavy water and ice have been studied in detail by a large number of workers though not always with concurrent results. An investigation has been made on their Raman spectra by the present author employing the Rasetti technique of utilising the A 2536-5 resonance radiation of the mercury ...

  16. Removal of gadolinium nitrate from heavy water

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W.

    2000-03-22

    Work was conducted to develop a cost-effective process to purify 181 55-gallon drums containing spent heavy water moderator (D2O) contaminated with high concentrations of gadolinium nitrate, a chemical used as a neutron poison during former nuclear reactor operations at the Savannah River Site (SRS). These drums also contain low level radioactive contamination, including tritium, which complicates treatment options. Presently, the drums of degraded moderator are being stored on site. It was suggested that a process utilizing biological mechanisms could potentially lower the total cost of heavy water purification by allowing the use of smaller equipment with less product loss and a reduction in the quantity of secondary waste materials produced by the current baseline process (ion exchange).

  17. Assay of the deuterium enrichment of water via acetylene.

    Science.gov (United States)

    Previs, S F; Hazey, J W; Diraison, F; Beylot, M; David, F; Brunengraber, H

    1996-06-01

    A technique is presented for measuring the 2H enrichment of water in biological samples when this enrichment is greater than 0.2%. The sample is reacted with calcium carbide to form acetylene gas, which is determined by gas chromatography electron impact ionization mass spectrometry. Ion-molecule reactions, resulting in proton abstraction, are minimized by lowering the electron ionization energy from the usual 70 eV to 45 eV. This technique is much more rapid and economical than the classical isotope ratio mass spectrometric assay of the enrichment of hydrogen gas derived from reduction of water.

  18. Concentration, enrichment and distribution of heavy metals in surface sediments of the Tangier Bay, Morocco

    Directory of Open Access Journals (Sweden)

    María Rocío Rodríguez-Barroso

    2010-11-01

    Full Text Available The distribution, enrichment, and accumulation of heavy metals in the surface sediments of the Tangier Bay, Morocco, were investigated. Surface sediment samples from eleven locations in the Bay of Tangier were collected in 2007 and characterized for grain size, organic matter and metal content (e.g. Fe, Mn, Cr, Cu, Ni, Pb, Zn and Cd. The evaluation of the heavy metal contamination status of the bay showed minor enrichment by the enrichment factors (EF calculation, corroborated by the metal pollution index (MPI. The results of a Pearson correlation showed high positive correlations among organic carbon and most metals (0.788 < r < 0.939 and cluster analysis grouped the stations inside the harbour (stations 1, 10 and 9 and in the vicinity of the principal rivers in the bay (stations 3 and 11, which showed the highest concentrations of metal content. The main sources of contamination are domestic and industrial effluents, which arise due to the lack of sewage treatment. However, these areas could not be classified as polluted when the data were compared with sediment quality guidelines (USEPA, 1997.

  19. Heavy Metal Concentrations in Maltese Potable Water

    Directory of Open Access Journals (Sweden)

    Roberta Bugeja

    2015-05-01

    Full Text Available This study evaluates the levels of aluminum (Al, cadmium (Cd, chromium (Cr, copper (Cu, iron (Fe, lead (Pb, nickel (Ni and zinc (Zn in tap water samples of forty localities from around the Maltese Islands together with their corresponding service supply reservoirs. The heavy metal concentrations obtained indicated that concentrations of the elements were generally below the maximum allowed concentration established by the Maltese legislation. In terms of the Maltese and EU water quality regulations, 17.5% of the localities sampled yielded water that failed the acceptance criteria for a single metal in drinking water. Higher concentrations of some metals were observed in samples obtained at the end of the distribution network, when compared to the concentrations at the source. The observed changes in metal concentrations between the localities’ samples and the corresponding supply reservoirs were significant. The higher metal concentrations obtained in the samples from the localities can be attributed to leaching in the distribution network.

  20. HEAVY WATER COMPONENTS TEST REACTOR DECOMMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Austin, W.; Brinkley, D.

    2011-10-13

    The Heavy Water Components Test Reactor (HWCTR) Decommissioning Project was initiated in 2009 as a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Removal Action with funding from the American Recovery and Reinvestment Act (ARRA). This paper summarizes the history prior to 2009, the major D&D activities, and final end state of the facility at completion of decommissioning in June 2011. The HWCTR facility was built in 1961, operated from 1962 to 1964, and is located in the northwest quadrant of the Savannah River Site (SRS) approximately three miles from the site boundary. The HWCTR was a pressurized heavy water test reactor used to develop candidate fuel designs for heavy water power reactors. In December of 1964, operations were terminated and the facility was placed in a standby condition as a result of the decision by the U.S. Atomic Energy Commission to redirect research and development work on heavy water power reactors to reactors cooled with organic materials. For about one year, site personnel maintained the facility in a standby status, and then retired the reactor in place. In the early 1990s, DOE began planning to decommission HWCTR. Yet, in the face of new budget constraints, DOE deferred dismantlement and placed HWCTR in an extended surveillance and maintenance mode. The doors of the reactor facility were welded shut to protect workers and discourage intruders. In 2009 the $1.6 billion allocation from the ARRA to SRS for site footprint reduction at SRS reopened the doors to HWCTR - this time for final decommissioning. Alternative studies concluded that the most environmentally safe, cost effective option for final decommissioning was to remove the reactor vessel, both steam generators, and all equipment above grade including the dome. The transfer coffin, originally above grade, was to be placed in the cavity vacated by the reactor vessel and the remaining below grade spaces would be grouted. Once all above equipment

  1. Material Removes Heavy Metal Ions From Water

    Science.gov (United States)

    Philipp, Warren H., Jr.; Street, Kenneth W.; Hill, Carol; Savino, Joseph M.

    1995-01-01

    New high capacity ion-exchange polymer material removes toxic metal cations from contaminated water. Offers several advantages. High sensitivities for such heavy metals as lead, cadmium, and copper and capable of reducing concentrations in aqueous solutions to parts-per-billion range. Removes cations even when calcium present. Material made into variety of forms, such as thin films, coatings, pellets, and fibers. As result, adapted to many applications to purify contaminated water, usually hard wherever found, whether in wastewater-treatment systems, lakes, ponds, industrial plants, or homes. Another important feature that adsorbed metals easily reclaimed by either destructive or nondestructive process. Other tests show ion-exchange polymer made inexpensively; easy to use; strong, flexible, not easily torn; and chemically stable in storage, in aqueous solutions, and in acidic or basic solution.

  2. Heavy Water Vodka: flawless purity and award winning design

    OpenAIRE

    Storås, Arill; Sandbu, Kristoffer; Eriksen, Sandra Kristine; Isene, Frode

    2008-01-01

    This thesis presents the findings from an explorative research study of the Chinese vodka market. The research has been conducted on behalf of Heavy Water International, a Norwegian vodka producer. Heavy Water International believes that the vodka market in China has considerable growth potential the next 5-10 years, and wants to enter the Chinese vodka market within 2008. Their first goal is to establish a good distributor-connection and create brand awareness. Heavy Water ...

  3. assessment of heavy metals concentrations in the surface water of ...

    African Journals Online (AJOL)

    User

    This work aimed at assessing the concentrations of heavy metals in the surface water of Bompai-. Jakara drainage basin. The points of ... Keywords: Heavy metals, surface water, drainage basin, standard limit. INTRODUCTION. Water pollution in .... discrepancies in values obtained. Pb concentrations recorded in this study ...

  4. incidence of heavy metals in kano metropolis drinking water sources ...

    African Journals Online (AJOL)

    userpc

    into these sources as domestic sewage might be of kitchen and toilet origin heavily accumulated with soaps of heavy metals constituents. Heavy metal contamination with ... Water pollution has been a major challenge which requires ongoing evaluation. (Okonko et al., 2008).Presence of excessive amounts of heavy metals ...

  5. Air-Xe enrichments in Elk Hills oil field gases: role of water in migration and storage

    Science.gov (United States)

    Torgersen, T.; Kennedy, B. M.

    1999-04-01

    Hydrocarbons from the Elk Hills Naval Petroleum Reserve (NPR#1), Bakersfield, CA, are enriched in heavy noble gases. The 132Xe/ 36Ar ratios are as high as ˜576 times the ratio in air and represent the largest relative Xe-enrichments ever observed in terrestrial fluids. The Xe isotopic composition is indistinguishable from air. We show that these samples cannot be explained by equilibration of oil with air saturated water and secondary enrichment via a Rayleigh distillation gas stripping process. Based on laboratory studies of others with potential petroleum source rocks, we believe the source of this enriched heavy noble gas component was adsorbed air initially trapped in/on the source rocks that was expelled and mixed with the hydrocarbons during expulsion and primary migration. Kr and Xe enrichments decrease with increasing 36Ar concentration. We propose a model in which an initial Kr-Xe-enriched hydrocarbon becomes diluted with noble gases extracted from air saturated groundwater during expulsion, migration, and storage. The model generates an integrated water/hydrocarbon ratio for the production fluid which indicates a minimal role for water in hydrocarbon expulsion and migration. The results are interpreted to provide time/geometrical constraints on the mechanisms by which hydrocarbons can migrate as a separate phase.

  6. Enrichment of marsh soils with heavy metals by effect of anthropic pollution

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Flora A.; Covelo, Emma F.; Cerqueira, Beatriz [Departamento de Biologia Vegetal y Ciencia del Suelo, Universidad de Vigo, As Lagoas. Marcosende 4, 36310 Vigo (Spain); Andrade, Maria Luisa, E-mail: mandrade@uvigo.es [Departamento de Biologia Vegetal y Ciencia del Suelo, Universidad de Vigo, As Lagoas. Marcosende 4, 36310 Vigo (Spain)

    2009-10-30

    The impact of waste disposal on marsh soils was assessed in topsoil samples collected at eight randomly selected points in the salt marsh in Ramallosa (Pontevedra, Spain) at 4-month intervals for 2 years. Polluted soil samples were characterized in physico-chemical terms and their heavy metal contents determined by comparison with control, unpolluted samples. The results revealed a marked effect of waste discharges on the soils in the area, which have low contents in heavy metals under normal environmental conditions. In fact, the studied soils were found to contain substantial amounts of total and DTPA-extractable Cd, Cu, Pb and Zn. Based on the relationship of the redox potential with the DTPA-extractable Cd, Cu, Pb, and Zn contents of the soils, strongly reductive conditions raised the total contents in these elements by effect of their remaining in the soils as precipitated sulphides. Such contents, however, decreased as oxidative conditions gradually prevailed. The contents in DTPA-extractable metals increased with increasing Eh through the release of the metals in ionic form to the soil solution under oxidative conditions. The contents in heavy metals concentrating in the polluted soils were several times higher than those in the control soils (viz. 2 vs. 6 for Cd, 4 vs. 6 for Cu, 4 vs. 20 for Pb, and 2 vs. 15 for Zn, all in mg kg{sup -1}). This can be expected to influence the amounts of available heavy metals present in the soils, and hence the environmental quality of the area, in the near future. Based on its geoaccumulation index (Class {>=}3 for Cd and Cu, and 1-4 for Pb and Zn), the Ramallosa marsh is highly polluted with Cd and moderately to highly polluted with Cu, Pb and Zn. The enrichment factors obtained confirm that the salt marsh is highly polluted (especially with Cd) as the primary result of anthropic activity.

  7. Water Quality: Water Education for Teachers. A 4-H School Enrichment Program.

    Science.gov (United States)

    Powell, G. Morgan; Kling, Emily B.

    This looseleaf notebook is a teacher resource package that is designed for enrichment program use. It contains five units dealing with water quality: (1) The Water Cycle; (2) Our Water Supply; (3) Waste/Water Treatment; (4) Water Conservation; (5) Water Pollution. The units provide background information, experiments, stories, poems, plays, and…

  8. Distribution, enrichment, and source identification of selected heavy metals in surface sediments of the Siran River, Mansehra, Pakistan.

    Science.gov (United States)

    Raza, Ahmed; Farooqi, Abida; Javed, Asif; Ali, Waqar

    2016-10-01

    To assess the trace metal pollution in the Siran River, sediments were collected from 12 sites, from the left and right banks of the river in 2013. The concentrations, accumulation, distribution pattern, and pollution status of heavy metals in sediments were investigated using geoaccumulation index (I geo) and enrichment factor (EF). The toxic risk of heavy metals was assessed using interim sediment quality guidelines (ISQGs), portable effect level (PEL), threshold effect level (TEL), and toxic effect threshold (TET). I geo and EF values showed that sediments were loaded with Ni, Cd, Pb, and Co and no obvious variations were found among the left and right banks of the river. The EF and I geo values were found in order of Co > Pb > Ni > As > Cd > Cu > Zn > Fe and Cd > Co > Pb > Ni > As > Fe > Zn > Cu > Mn, respectively. Furthermore, multivariate statistical analysis like inter-metal correlation, cluster analysis (CA), and principal component analysis (PCA) results revealed that geogenic and anthropogenic activities were major sources of sediment contamination in the study area. These results indicated that more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution.

  9. Determination of heavy metals and genotoxicity of water from an ...

    African Journals Online (AJOL)

    Thus, the present study aimed to quantify and evaluate the heavy metal genotoxicity of artesian water in the city by Atomic absorption spectrophotometer analysis and testing with the Allium cepa test, respectively. This study reveals a chemical contamination in well water in the city, caused by the presence of heavy metals.

  10. Distribution and enrichment of heavy metals in Sabratha coastal sediments, Mediterranean Sea, Libya

    Science.gov (United States)

    Nour, Hamdy E.; El-Sorogy, Abdelbaset S.

    2017-10-01

    In order to assess heavy metal pollutants in Sabratha coastal sediments, Mediterranean Sea, Libya, 30 sediment samples were collected for Fe, Cu, Pb, Mn, Cd, Co, Ni and Zn analysis using Atomic Absorption Spectrometry. The analysis indicated that, the Sabratha 's coastal sediments were enriched with Cd, Pb, Cu, Ni, Co and Zn (EF = 81.48, 17.26, 12.80, 11.42, 9.85 and 8.56 respectively). The highest levels of Mn, Cu, Ni, Pb and Co were recorded nearby the Mellitah complex oil and gas station in the western Libyan region, while the highest levels of Zn and Cd were recorded at the central part of the study area nearby fishing port and Sabratha hospital. Average values of Cd, Pb and Co were mostly higher than the ones recorded from the Arabian and Oman gulfs, the Red Sea, the Gulf of Aqaba, the Caspian Sea, coast of Tanzania and the background shale and the earth's crust. The high levels of most of the studied heavy metals suggested significant anthropogenic sources along Sabratha coast. The results of the present study provide a useful background for further marine studies on the Mediterranean area.

  11. [Effect of Recycled Water Irrieation on Heavy Metal Pollution in Irrigation Soil].

    Science.gov (United States)

    Zhou, Yi-qi; Liu, Yun-xia; Fu, Hui-min

    2016-01-15

    With acceleration of urbanization, water shortages will become a serious problem. Usage of reclaimed water for flushing and watering of the green areas will be common in the future. To study the heavy metal contamination of soils after green area irrigation using recycled wastewater from special industries, we selected sewage and laboratory wastewater as water source for integrated oxidation ditch treatment, and the effluent was used as irrigation water of the green area. The irrigation units included broad-leaved forest, bush and lawn. Six samples sites were selected, and 0-20 cm soil of them were collected. Analysis of the heavy metals including Cr, Mn, Ni, Cu, Zn, As, Cd and Pb in the soil showed no significant differences with heavy metals concentration in soil irrigated with tap water. The heavy metals in the soil irrigated with recycled water were mainly enriched in the surface layer, among which the contents of Cr, Ni, Cu, Zn and Pb were below the soil background values of Beijing. A slight pollution of As and Cd was found in the soil irrigated by recycled water, which needs to be noticed.

  12. Heavy Metals Pollution on Surface Water Sources in Kaduna ...

    African Journals Online (AJOL)

    Heavy Metals Pollution on Surface Water Sources in Kaduna Metropolis, Nigeria. JA Aliyu, Y Saleh, S Kabiru. Abstract. This study examine the effects of heavy metal pollutants to aquatic ecosystems and the environment by considering the role of urban, municipal, agricultural, industrial and other anthropogenic processes ...

  13. Environmental assessment of ground water pollution by heavy ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the relationship between the concentrations of heavy metals in well water and bioaccumulation of the most abundant metals in chicken tissues in some areas in the province of Mecca Almokaramah, Saudi Arabia. Among the heavy metals (Cd, Zn, Cr, Mn, Cu Hg, Pb and Ni) studied, ...

  14. Urban water pollution by heavy metals and health implication in ...

    African Journals Online (AJOL)

    Studies of common heavy metals were conducted at Onitsha, Anambra State, the most urbanized city in Southeastern Nigeria. It was discovered that both surface and subsurface water were heavily polluted. Seven (7) heavy metals namely: arsenic (As+2), cadmium (Cd+2), lead (Pb+2), mercury (Hg+2), zinc (Zn+2), copper ...

  15. heavy metals pollution on surface water sources in kaduna ...

    African Journals Online (AJOL)

    ABSTRACT. This study examine the effects of heavy metal pollutants to aquatic ecosystems and the environment by considering the role of urban, municipal, agricultural, industrial and other anthropogenic processes as sources of heavy metal pollution in surface water sources of Kaduna metropolis. Samples of the polluted ...

  16. Determination of heavy metals in water sediments and Tilapia zilli ...

    African Journals Online (AJOL)

    The study investigated the heavy metal concentration in Tilapia zilli and water sediments along Kolo Creek in Ogbia Local Government Area, Bayelsa State. Tilapia fish and sediment samples were collected from 5 stations, and analyzed for heavy metals following standard procedures. Four metals (Copper, Lead. Cadmium ...

  17. assessment of heavy metal concentration in water around the ...

    African Journals Online (AJOL)

    nb

    lead, nickel and zinc (EU 1998, TBS 2005,. WHO 2008).When heavy metal concentrations in water exceed ... that the dependency of heavy metal concentration on rainfall variations can be complex (Meybeck ..... IAEA 2009 Nuclear energy series establishment of uranium mining and processing operations in the context of ...

  18. Biogenic precipitation of manganese oxides and enrichment of heavy metals at acidic soil pH

    Science.gov (United States)

    Mayanna, Sathish; Peacock, Caroline L.; Schäffner, Franziska; Grawunder, Anja; Merten, Dirk; Kothe, Erika; Büchel, Georg

    2014-05-01

    The precipitation of biogenic Mn oxides at acidic pH is rarely reported and poorly understood, compared to biogenic Mn oxide precipitation at near neutral conditions. Here we identified and investigated the precipitation of biogenic Mn oxides in acidic soil, and studied their role in the retention of heavy metals, at the former uranium mining site of Ronneburg, Germany. The site is characterized by acidic pH, low carbon content and high heavy metal loads including rare earth elements. Specifically, the Mn oxides were present in layers identified by detailed soil profiling and within these layers pH varied from 4.7 to 5.1, Eh varied from 640 to 660 mV and there were enriched total metal contents for Ba, Ni, Co, Cd and Zn in addition to high Mn levels. Using electron microprobe analysis, synchrotron X-ray diffraction and X-ray absorption spectroscopy, we identified poorly crystalline birnessite (δ-MnO2) as the dominant Mn oxide in the Mn layers, present as coatings covering and cementing quartz grains. With geochemical modelling we found that the environmental conditions at the site were not favourable for chemical oxidation of Mn(II), and thus we performed 16S rDNA sequencing to isolate the bacterial strains present in the Mn layers. Bacterial phyla present in the Mn layers belonged to Firmicutes, Actinobacteria and Proteobacteria, and from these phyla we isolated six strains of Mn(II) oxidizing bacteria and confirmed their ability to oxidise Mn(II) in the laboratory. The biogenic Mn oxide layers act as a sink for metals and the bioavailability of these metals was much lower in the Mn layers than in adjacent layers, reflecting their preferential sorption to the biogenic Mn oxide. In this presentation we will report our findings, concluding that the formation of natural biogenic poorly crystalline birnessite can occur at acidic pH, resulting in the formation of a biogeochemical barrier which, in turn, can control the mobility and bioavailability of heavy metals in

  19. Enrichment and assessment of the health risks posed by heavy metals in PM1 in Changji, Xinjiang, China.

    Science.gov (United States)

    Liu, Yu Y; Shen, Ya X; Liu, Cheng; Liu, Hao F

    2017-04-16

    The present study aims to investigate the influence of human activity on heavy metals in a typical arid urban area of China and assess human health risks posed by heavy metals in PM1 (particles metals. The results indicated that Mn was not enriched; Co, Cu, Cr, Ni, Tl, and V were slightly enriched; Mo, Pb, and Sb were moderately enriched; and Ag, As, and Cd were strongly enriched. To assess the health risks associated with inhaling PM1, the risk assessment code and loss in life expectancy based on the individual metals were calculated. The results showed that the elements Ag, Cu, Mo, Pb, Sb, Tl, and V in PM1 posed low levels of non-carcinogenic risks, but these metals may still pose risks to certain susceptible populations. In addition, the results also showed that As, Co, and Cr posed an appreciable carcinogenic risk, while Cd and Ni posed low levels of carcinogenic risk. The total predicted loss of life expectancy caused by the three metals As, Co, and Ni was 63.67 d for the elderly, 30.95 d for adult males, 26.62 d for adult females, and 48.22 d for children. Therefore, the safety of the elderly and children exposed to PM1 should be given more attention than the safety of adults. The results from this study demonstrate that the health risks posed by heavy metals in PM1 in Changji, Xinjiang, China should be examined.

  20. Heavy-ion beam induced effects in enriched gadolinium target films prepared by molecular plating

    Science.gov (United States)

    Mayorov, D. A.; Tereshatov, E. E.; Werke, T. A.; Frey, M. M.; Folden, C. M.

    2017-09-01

    A series of enriched gadolinium (Gd, Z = 64) targets was prepared using the molecular plating process for nuclear physics experiments at the Cyclotron Institute at Texas A&M University. After irradiation with 48Ca and 45Sc projectiles at center-of-target energies of Ecot = 3.8-4.7 MeV/u, the molecular films displayed visible discoloration. The morphology of the films was examined and compared to the intact target surface. The thin films underwent a heavy-ion beam-induced density change as identified by scanning electron microscopy and α-particle energy loss measurements. The films became thinner and more homogenous, with the transformation occurring early on in the irradiation. This transformation is best described as a crystalline-to-amorphous phase transition induced by atomic displacement and destruction of structural order of the original film. The chemical composition of the thin films was surveyed using energy dispersive spectroscopy and X-ray diffraction, with the results confirming the complex chemistry of the molecular films previously noted in other publications.

  1. SPECIATION OF HEAVY METALS AT WATER-SEDIMENT INTERFACE

    Directory of Open Access Journals (Sweden)

    Chiara Ferronato

    2013-09-01

    Full Text Available The objective of the study was to understand the equilibrium relationship between the heavy metals concentrations in superficial water and pore water. At  water-sediment interface, the equilibrium rapidly changed and it is influenced by chemico-physical parameters of aquatic ecosystems. The hydraulic safety of Bologna plain (North Italy depends on network of artificial canals and they are related with natural rivers of Reno basin (Reno river and its tributaries. The natural and artificial water courses flowed in agricultural, urban and industrial land. The heavy metals concentration in water and sediment discriminated the human pressure on the land and their spatial distribution in sediment could predict the hazard of pollution in aquatic ecosystems. We compared the heavy metals concentrations in pore water and superficial water determined in natural rivers and artificial canals, and more pollution in artificial canals than natural rivers was found. Furthermore, the coefficient of partition (log Kd between water and sediments was calculated to evaluate the bioavailability of heavy metals adsorbed on the sediments. The heavy metals extracted in deionised water at equilibrium after 16 h showed higher concentrations than those determined directly on water samples.

  2. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China

    OpenAIRE

    Huixuan Li; Yingru Li; Ming-Kuo Lee; Zhongwei Liu; Changhong Miao

    2015-01-01

    China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1) spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2) spatial statistical met...

  3. Three-component U-Pu-Th fuel for plutonium irradiation in heavy water reactors

    Directory of Open Access Journals (Sweden)

    Peel Ross

    2016-01-01

    Full Text Available This paper discusses concepts for three-component fuel bundles containing plutonium, uranium and thorium for use in pressurised heavy water reactors, and cases for and against implementation of such a nuclear energy system in the United Kingdom. Heavy water reactors are used extensively in Canada, and are deploying within India and China, whilst the UK is considering the use of heavy water reactors to manage its plutonium inventory of 140 tonnes. The UK heavy water reactor proposal uses a mixed oxide (MOX fuel of plutonium in depleted uranium, within the enhanced CANDU-6 (EC-6 reactor. This work proposes an alternative heterogeneous fuel concept based on the same reactor and CANFLEX fuel bundle, with eight large-diameter fuel elements loaded with natural thorium oxide and 35 small-diameter fuel elements loaded with a MOX of plutonium and reprocessed uranium stocks from UK MAGNOX and AGR reactors. Indicative neutronic calculations suggest that such a fuel would be neutronically feasible. A similar MOX may alternatively be fabricated from reprocessed <5% enriched light water reactor fuel, such as the fuel of the AREVA EPR reactor, to consume newly produced plutonium from reprocessing, similar to the DUPIC (direct use of PWR fuel in CANDU process.

  4. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R

    1991-01-01

    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  5. Concentration of Heavy Metals in Drinking Water from Urban Areas ...

    African Journals Online (AJOL)

    Bheema

    implications. This study, therefore, recommends the government and other responsible authorities to take appropriate corrective measures. Key words: Drinking water quality, Heavy metals, Maximum admissible limit, World health organization, Tigray. 1. INTRODUCTION. Safe drinking water is a human birthright – as much ...

  6. Heavy metals concentrations in water bodies around aquamarine ...

    African Journals Online (AJOL)

    Water samples from three streams in the mining area of Eggon Hill were analysed. The Physicochemical values obtained were compared with WHO permissible standards in drinking water. Except for Cu and Zn with levels within permissible limits, other heavy metals determined were found to have levels above the WHO ...

  7. Determination of selected heavy metals in inland fresh water of ...

    African Journals Online (AJOL)

    The concentrations of some ferruginous ore associated heavy metals were determined in freshwater from River Niger. Water samples were collected from both upstream and downstream along the mainstream drainage channel, traversing past the steel production industry Ajaokuta between 2003 and 2005. The water ...

  8. Heavy metal contamination in stream water and sediments of gold ...

    African Journals Online (AJOL)

    This study assessed the seasonal variation in heavy metal contamination of stream water and sediments in the gold mining area of Atakunmosa West local Government, Osun State, Nigeria. Twelve villages of prominence in illegal gold mining were selected for the study covering dry and wet seasons of 2012. Stream water ...

  9. Assessment of Heavy Metal Pollution in Drinking Water Due to ...

    African Journals Online (AJOL)

    Akorede

    water sources. The toxicity of these heavy metals from the mining, milling and smelting companies can cause harmful and even lethal effects on the human health. The objective of this study was to investigate the level of As, Cr, Zn,. Mg, Fe, Pb, Cd, Cu, Ag and Mn in well and tap water and assess the degree of pollution in ...

  10. Assessment of heavy metal concentration in water around the ...

    African Journals Online (AJOL)

    Effective verification for compliance with water quality standards in uranium mining in Tanzania requires data sensitive to monitor heavy metal concentration in water around the Mkuju River Uranium Project before mining commences. The area susceptible for pollution by the project was estimated using AERMOD ...

  11. Heavy metal concentrations in water, sediment and periwinkle ...

    African Journals Online (AJOL)

    Heavy metal concentration in water, sediment and Periwinkle samples from three locations (Itu-River, Abuloma River and Oron River) in the Niger Delta Region of Nigeria were evaluated using atomic absorption flame photometry. Result showed that cadmium (Cd) concentration was highest in water samples from Abuloma ...

  12. Assessment of Heavy Metals Concentrations in the Surface Water of ...

    African Journals Online (AJOL)

    This work aimed at assessing the concentrations of heavy metals in the surface water of Bompai-Jakara drainage basin. The points of sampling were designated as A, B, C, D, E, and F. Acid-washed (1L) plastic bottles were used in collecting the water samples, which were then digested using nitric acid (HNO3).

  13. Contaminations Of Heavy Metals In Water And Hemichromis ...

    African Journals Online (AJOL)

    ... Co and Cr exceeding WHO limits for some months. The findings reveal that the water and the fish (H. fasciatus) are contaminated and not fit for drinking and consumption by humans. Keywords: Heavy metals, water, fish, seasonality, distribution coefficients, burrow pit, Niger Delta, Nigeria. Tropical Freshwater Biology Vol.

  14. Heavy Metal Enrichment History in annually laminated Lake Tiefer See (NE-Germany) and Lake Czechowskie (N-Poland)

    Science.gov (United States)

    Hoelzmann, Philipp; Dräger, Nadine; Kienel, Ulrike; Ott, Florian; Brauer, Achim

    2015-04-01

    Within the Virtual Institute of Integrated Climate and Landscape Evolution Analyses (ICLEA) high-resolution geo-archives (e.g. lakes as natural data loggers) of the northeastern german and northern polish lowlands are investigated to identify influences of land-use on the landscape evolution. For two annually laminated lake sediment records, situated in rural environments in NE-Germany (Lake Tiefer See) and N-Poland (Czechowskie Lake), we present a detailed heavy metal enrichment history for Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn for the last two hundred years at 1 cm intervals. Both lakes show a similar pattern of relatively low heavy metal concentrations if compared to the so-called index of geoaccumulation (Müller 1979), which is based on the average global metal content in shales (Turekian and Wedepohl, 1961). Only Pb, Zn and Cd show a clear parallel pattern of enrichment in both lakes starting around 1850 according to mainly atmospheric input due to increasing industrialization within the framework of the Industrial Revolution. Highest input for Cd, Zn, and Pb occur around 1960 to 1980 and thereafter a clear pattern of declining anthropogenic input is registered. On the base of heavy-metal analysis of pre-industrial sediments and different sediment types (e.g. calcareous gyttja, organic gyttja etc.) the local and specific geogenic background values for various metals are determined. These results provide means to calculate and quantify with sub-decadal resolution anthropogenic heavy metal accumulations and enrichment factors as well as to define regional measures for a state of reference, reflecting natural conditions without human impact. Müller, G. (1979): Schwermetalle in den Sedimenten des Rheins - Veränderungen seit 1971. Umschau 79: 778-783. Turekian, K. and Wedepohl, K. (1961): Distribution of the elements in some major units of the earth's crust. Bull.Geol.Soc.Am. 72: 175-192.

  15. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China

    Directory of Open Access Journals (Sweden)

    Huixuan Li

    2015-07-01

    Full Text Available China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1 spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2 spatial statistical methods were used to examine the underlying socioeconomic and physical factors behind water pollution including socioeconomic transitions (industrialization, urbanization, globalization and economic development, and environmental characteristic (natural resources, hydrology and vegetation coverage. The results show that only Cr pollution levels increased over the years. The individual pollution levels of the other four heavy metals, As, Cd, Hg, and Pb, declined. High heavy metal water pollution levels are closely associated with both anthropogenic activities and physical environments, in particular abundant mineral resources and industrialization prosperity. On the other hand, economic development and urbanization play important roles in controlling water pollution problems. The analytical findings will provide valuable information for policy-makers to initiate and adjust protocols and strategies for protecting water sources and controlling water pollution; thus improving the quality of living environments.

  16. Heavy metal removal and speciation transformation through the calcination treatment of phosphorus-enriched sewage sludge ash.

    Science.gov (United States)

    Li, Rundong; Zhao, Weiwei; Li, Yanlong; Wang, Weiyun; Zhu, Xuan

    2015-01-01

    On the basis of the heavy metal (Cd, As, Pb, Zn, Cu, Cr, and Ni) control problem during the thermochemical recovery of phosphorus (P) from sewage sludge (SS), P-enriched sewage sludge ash (PSSA) was calcined at 1100°C. The effect of organic chlorinating agent (PVC) and inorganic chlorinating agent (MgCl2) on the fixed rate of P removal and the speciation transformation of heavy metal was studied. The removal of heavy metals Cd, Pb, As, Zn, and Cr exhibited an increasing tendency with the addition of chlorinating agent (PVC). However, an obvious peak under 100gCl/kg of PSSA appeared for Cu, owing to the presence of carbon and hydrogen in PVC. MgCl2 was found to be more effective than PVC in the removal of most heavy metals, such that up to 98.9% of Cu and 97.3% of Zn was effectively removed. Analyses of heavy metal forms showed that Pb and Zn occurred in the residue fraction after calcination. Meanwhile, the residue fraction of Cr, Ni, Cd, and Cu exhibited a decreasing tendency with the increase in the added chlorinating agent (MgCl2). Losses of P from PSSA were around 16.6% without the addition of chlorinating agent, which were greatly reduced to around 7.7% (PVC) and to only 1.7% (MgCl2). Copyright © 2014 Elsevier B.V. All rights reserved.

  17. [Heavy metals in environmental media around drinking water conservation area of Shanghai].

    Science.gov (United States)

    Shi, Gui-Tao; Chen, Zhen-Lou; Zhang, Cui; Bi, Chun-Juan; Cheng, Chen; Teng, Ji-Yan; Shen, Jun; Wang, Dong-Qi; Xu, Shi-Yuan

    2008-07-01

    The levels of heavy metals in Shanghai drinking water conservation area were determined, and the spatial distributions and main sources of heavy metals were investigated. Moreover, the ecological risk assessment of heavy metals was conducted. Some conclusions can be drawn as follows: (1) The average concentrations of Cd, Hg, Pb, Cu, Zn, Ni, Cr and As in road dust were 0.80, 0.23, 148.45, 127.52, 380.57, 63.17, 250.38 and 10.37 mg x kg(-1) respectively. In terms of the pollution level, the values of soils were relatively lower, with the mean contents of 0.16 (Cd), 0.33 (Hg), 30.14 (Pb), 30.66 (Cu), 103.79 (Zn), 24.04 (Ni), 65.75 (Cr) and 6.31 mg x kg(-1) (As) severally; meanwhile the average levels of heavy metals in vegetables were 0.010 (Cd), 0.016 (Hg), 0.36 (Pb), 12.80 (Cu), 61.69 (Zn), 2.04 (Ni), 2.41 (Cr) and 0.039 mg x kg(-1) (As) respectively. (2) Semivariogram and multivariate analysis indicated that heavy metals pollution of soils was induced by anthropogenic activities mostly, and the pollutants produced by traffic were the major source of heavy metals in road dust. (3) The order for heavy metal enrichment coefficients of vegetables was as following: Zn (0.589) > Cu (0.412) > 0.102 (Ni) > Cd (0.059) > Cr (0.061) > Hg (0.056) > Pb (0.012) > As (0.007), and the results indicated that Cd and Zn in vegetables were mainly from the soils, and the other metals were probably from the pollutants in the atmosphere. (4) Sediments in drinking water conservation area were probably derived from soils around; however, there was no significant relationship between heavy metals contents of them. (5) The results of ecological risk assessment of heavy metals showed that heavy metals in soils were in no-warning to warning situation, and warning to light-warning situation for road dust and vegetables. The fuzzy synthesis judgment for all the environmental media around drinking water conservation area was warning to light-warning.

  18. NATURAL MINERAL WATER ENRICHED WITH MAGNESIUM IN CHILDREN WITH CONSTIPATIONS

    Directory of Open Access Journals (Sweden)

    I. N. Zakharova

    2013-01-01

    Full Text Available Characteristics of medicinal mineral waters as well as the role of magnesium in human organism activity and normal functioning of the gastrointestinal tract are discussed in this article. Aim: to study the influence of mineral water enriched with magnesium on stool of children suffering from constipations, to determine the appropriate dosage and tolerance to such water and to research the effect of the combination of mineral and artesian drinking water on the functioning of the intestines of children with constipations. Patients and methods: 60 patients with chronic constipations (30 — in the study group and 30 — in control group were included into the first study. Children from the study group were administered mineral water at the dosage of 3–5 ml/kg of the body weight 3 times per day, the treatment course was 10 days at hospital and after that — for 3 weeks in outpatient conditions. The second study included 45 children at the age of 3–15 years old, suffered from chronic constipations, who received sanatorium-and-spa treatment. Patients were divided into 2 groups: 25 were included into the main group, they were administered simultaneously medicinal mineral and artesian water. Mineral water was given at the dosage of 3–5 ml/kg of the body weight 3 times per day before eating. Artesian drinking water was given at the dosage of 6 ml/kg of body weight after eating. The duration of combination treatment was 21 days. Comparison group consisted of 20 children, receiving moderate mineral water. During the first study clinical examination of children was performed, the number of defecation was assessed and the blood samples were performed. During the second study clinical effect of mineral water in the form of regular formed stool was assessed. Results: data from the first study allow to recommend mineral water in treatment of children with chronic constipations as laxative agent at the dosage of 3–5 ml/kg of the body weight.

  19. Nanopolysaccharides for adsorption of heavy metal ions from water

    OpenAIRE

    Liu, Peng

    2014-01-01

    With population expansion and industrialization, heavy metal has become one of the biggest and most toxic water pollutants, which is a serious problem for human society today. The aim of this work is to explore the potential of nanopolysaccharides including nanocellulose and nanochitin to remove metal ions from contaminated water. The above nano-polysaccharides are of interest in water purification technologies due to their high surface area, high mechanical properties, and versatile surface ...

  20. Enrichment of omnivorous cercozoan nanoflagellates from coastal Baltic Sea waters.

    Directory of Open Access Journals (Sweden)

    Kasia Piwosz

    Full Text Available Free-living nano-sized flagellates are important bacterivores in aquatic habitats. However, some slightly larger forms can also be omnivorous, i.e., forage upon both bacterial and eukaryotic resources. This hitherto largely ignored feeding mode may have pronounced implications for the interpretation of experiments about protistan bacterivory. We followed the response of an uncultured group of omnivorous cercozoan nanoflagellates from the Novel Clade 2 (Cerc_BAL02 to experimental food web manipulation in samples from the Gulf of Gdańsk (Southern Baltic Sea. Seawater was either prefiltered through 5 µm filters to exclude larger predators of nanoflagellates (F-treatment, or prefiltered and subsequently 1∶10 diluted with sterile seawater (F+D-treatment to stimulate the growth of both, flagellates and bacteria. Initially, Cerc_BAL02 were rapidly enriched under both conditions. They foraged on both, eukaryotic prey and bacteria, and were highly competitive at low concentrations of food. However, these omnivores were later only successful in the F+D treatment, where they eventually represented almost one fifth of all aplastidic nanoflagellates. By contrast, their numbers stagnated in the F-treatment, possibly due to top-down control by a concomitant bloom of other, unidentified flagellates. In analogy with observations about the enrichment of opportunistically growing bacteria in comparable experimental setups we suggest that the low numbers of omnivorous Cerc_Bal02 flagellates in waters of the Gulf of Gdańsk might also be related to their vulnerability to grazing pressure.

  1. Utilizing heavy metal-laden water hyacinth biomass in vermicomposting.

    Science.gov (United States)

    Tereshchenko, Natalya N; Akimova, Elena E; Pisarchuk, Anna D; Yunusova, Tatyana V; Minaeva, Oksana M

    2015-05-01

    We studied the efficiency of water treatment by water hyacinth (Eichhornia crassipes) from heavy metals (Zn, Cd, Pb, Cu), as well as a possibility of using water hyacinth biomass obtained during treatment for vermicomposting by Eisenia fetida and the vermicompost quality in a model experiment. The results showed that the concentration of heavy metals in the trials with water hyacinth decreased within 35 days. We introduced water hyacinth biomass to the organic substrate for vermicomposting, which promoted a significant weight gain of earthworms and growth in their number, as well as a 1.5- to 3-fold increase in coprolite production. In the trial with 40 % of Eichhornia biomass in the mixture, we observed a 26-fold increase in the number and a 16-fold weight gain of big mature individuals with clitellum; an increase in the number of small individuals 40 times and in the number of cocoons 140 times, as compared to the initial substrate. The utilization of water hyacinth biomass containing heavy metals in the mixture led to a 10-fold increase in the number of adult individuals and cocoons, which was higher than in control. We found out that adding 10 % of Eichhornia biomass to the initial mixture affected slightly the number of microorganisms and their species diversity in the vermicompost. Adding Eichhornia biomass with heavy metals reduced the total number of microorganisms and sharply diminished their species diversity. In all trials, adding water hyacinth in the mixture for vermicomposting had a positive impact on wheat biometric parameters in a 14-day laboratory experiment, even in the trial with heavy metals.

  2. Safety Evaluation of Osun River Water Containing Heavy Metals and ...

    African Journals Online (AJOL)

    olayemitoyin

    1Environmental, Analytical and Nutritional Chemistry Research Laboratory, Department of Chemical Sciences,. Osun State University ... Summary: This study evaluated the pH, heavy metals and volatile organic compounds (VOCs) in Osun river water. It also evaluated its ..... toxicity of pollutants. ALT and AST are markers of.

  3. levels of heavy metals in gubi dam water bauchi, nigeria

    African Journals Online (AJOL)

    Ada

    rivers to the ocean is in the form of particulate ... B.M. Wufem, Chemistry Programme, Abubakar Tafawa Balewa University, P.M.B. 0248, Bauchi. A.Q. Ibrahim ..... Chemistry. Wiley Interscience NY, p. 780. Sukiman, S.B., 1989. The determination of heavy metals in water, suspended materials and sediments from Langat River,.

  4. Water quality characteristics and pollution levels of heavy metals in ...

    African Journals Online (AJOL)

    The main aim of this study was to assess the level of water quality of Lake Haiq, Ethiopia with respect to selected physical parameters and heavy metals. Parameters such as temperature, pH, turbidity, electrical conductivity and total dissolved solids were measured in situ. While total alkalinity, chloride, ammonia, nitrate and ...

  5. Concentrations of heavy metals in untreated produced water from a ...

    African Journals Online (AJOL)

    product, residue or waste. One of such is an effluent from the mining of crude oil and gas, known as produced water, which contains varying quantities of hydrocarbons and heavy metals, thereby making it to require proper treatment in order to ...

  6. Safety Evaluation of Osun River Water Containing Heavy Metals and ...

    African Journals Online (AJOL)

    Male and female rats were exposed to Osun river water for three weeks and then sacrificed. The abundance of heavy metals in Osun river followed the trend Pb > Cd > Zn > Fe > Cr > Cu while VOCs followed the trend benzene < ethylbenzene < toluene < xylene. The concentrations of Pb, Cd and benzene were higher than ...

  7. Heavy metal pollution levels in water and oysters, Saccostrea ...

    African Journals Online (AJOL)

    Heavy metal (cadmium, chromium, copper, mercury, lead and zinc) concentrations in mangrove forests were investigated in water, suspended particulate matter (SPM) and oyster samples from the Mzinga Creek and Ras Dege mangrove stands, Tanzania, using Inductively Coupled Plasma–Atomic Emission Spectroscopy.

  8. Search for DD-fusion neutrons during heavy water electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Seeliger, D.; Wiesener, K.; Meister, A.; Marten, H.; Ohms, D.; Rahner, D.; Schwierz, R.; Wustner, P. (Technische Univ., Dresden (German Democratic Republic))

    1989-07-01

    The radiation obtained by the electrolysis of heavy water with a palladium cathode was measured, using a large volume liquid scintillation detector and some other neutron and gamma-ray detectors. An indication of a weak generation of fast neutrons (0.1 s{sup -1} of about 2.5 MeV) is found. (author).

  9. Physicochemical Characteristics and Heavy Metal Levels in Water ...

    African Journals Online (AJOL)

    MICHAEL

    ABSTRACT: Physicochemical characteristics and heavy metal levels in water samples from five river systems in central part of Delta State, Nigeria were investigated to access the quality status of the rivers. All the watersheds selected for study were well distributed and possessed similar geology, climate, soil, and ...

  10. Bioaccumulation of heavy metals in water, sediment and periwinkle ...

    African Journals Online (AJOL)

    The accumulation of three heavy metals; chromium (Cr), cadmium (Cd) and lead (Pb) in periwinkle (Tympanotonus fuscatus var radula; shell and soft tissues), water and sediment collected from four stations along Elechi Creek course was studied. Elechi Creek receives effluents discharges from heavily industrialized and ...

  11. Heavy metal enrichment in the seagrasses of Lakshadweep group of islands--a multivariate statistical analysis.

    Science.gov (United States)

    Thangaradjou, T; Raja, S; Subhashini, Pon; Nobi, E P; Dilipan, E

    2013-01-01

    An assessment on heavy metal (Al, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) accumulation by seven seagrass species of Lakshadweep group of islands was carried out using multivariate statistical tools like principal component analysis (PCA) and cluster analysis (CA). Among all the metals, Mg and Al were determined in higher concentration in all the seagrasses, and their values varied with respect to different seagrass species. The concentration of the four toxic heavy metals (Cd, Pb, Zn and Cu) was found higher in all the seagrasses when compared with the background values of seagrasses from Flores Sea, Indonesia. The contamination factor of these four heavy metals ranged as Cd (1.97-12.5), Cu (0.73-4.40), Pb (2.3-8.89) and Zn (1.27-2.787). In general, the Pollution Load Index (PLI) calculated was found to be maximum for Halophila decipiens (58.2). Results revealed that Halophila decipiens is a strong accumulator of heavy metals, followed by Halodule uninervis and Halodule pinifolia, among all the tested seagrasses. Interestingly, the small-leaved seagrasses were found to be efficient in heavy metal accumulation than the large-leaved seagrass species. Thus, seagrasses can better be used for biomonitoring, and seagrasses can be used as the heavy metal sink as the biomass take usually long term to get remineralize in nature.

  12. Obtaining for the first time in USSR heavy water samples of A. I. Brodskii’s laboratory in the country

    Directory of Open Access Journals (Sweden)

    Valerij S. Kovalenko

    2015-10-01

    Full Text Available This article is devoted to the significant event for national science – obtaining of initial portions of heavy (deuterium water. The receiving of heavy water by multiple-stage electrolysis was carried out by the group of Dnipropetrovsk scientists under the supervision of professor A I. Brodskii in summer 1934. The article dwells upon the prerequisites of discovery of heavy-hydrogen water, it shows the role of academician A. I. Brodskii in the organization and provision of scientific supervision of investigations. The authors adduce features of the experimental method used by the Dnipropetrovsk scientists (the multiple-stage electrolysis and also peculiarities of methods of control over the process of water enrichment by the heavy Hydrogen isotope (interferometric, differential and picnometric. The article tells about history of creation of experimental and semi-industrial equipment for obtaining heavy water. It accentuates the importance of Brodskii group’s success for the further development of research in the area of isotope chemistry and nuclear physics and also his role in solving of nuclear problem.

  13. Conceptual design of a large heavy water reactor for US siting

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, N L; Jesick, J F

    1979-09-01

    Information is presented concerning fuel management and safety and licensing assessment of the pressurized heavy water reactor; and commercial introduction of the pressurized heavy water reactor in the United States.

  14. Natural and anthropogenic enrichments of heavy metals in modern soils: the case study in the Jizera floodplain, Czech Republic

    Science.gov (United States)

    Matys Grygar, Tomas; Elznicova, Jitka; Vadinova, Nikola

    2013-04-01

    The timing and realistic quantification of the anthropogenic pollution of soils and sediments are among relevant topics of numerous current environmental geochemistry studies. Geochemical mapping and depth profiling of pollutants in soils and sediments is used for reconstruction of historical pollution and evaluation of previous (cumulative) impacts. In fact, the depth profiles of heavy metals in modern soils are a result of two main processes: deposition of atmospheric fallout (everywhere) or sediment (in floodplains) with anthropogenic components on one hand, and element migration due to biogeochemical processes (Fe oxide transformations, element recycling by plants and joint processes) on the other hand. These processes are not always taken into account, particularly when only one piece of the jigsaw puzzle is in focus, such as development of pollution proxy (e.g., stable lead isotope ratios, MS) or geochemical mapping. Mature soils, of which surface strata are enriched in heavy metals, are too complex systems to allow simple distinguishing natural and anthropogenic portions of that enrichment; possible natural enrichment factor (EF) ~1.5 has been assumed in the case of Pb and Zn by Reimann et al. Floodplains can offer a "natural isolation of pieces of jigsaw puzzle", if deposition and erosion in the floodplain have alternated in the past (such behaviour is relatively common). This alteration can produce terraces or related sediment units of different age, but composed of sediment with the same geochemistry, i.e. material with the same provenance and after the same hydraulic sorting before the deposition. We studied fluvisols in the Jizera floodplain (~50 north-east from Prague, Czech Republic), where a terrace is present along the currently inundated floodplain. We found that atmospheric fallout and/or past pedogenic processes in the terrace above that active floodplain do not cause enrichment of Cr, Cu, Ni, and Zn; perhaps there is an exception for Pb. In a

  15. 76 FR 52994 - Application for a License To Export Heavy Water

    Science.gov (United States)

    2011-08-24

    ... COMMISSION Application for a License To Export Heavy Water Pursuant to 10 CFR 110.70 (b) ``Public Notice of... end-use for China. (D2O--heavy (liters). producing an active water). pharmaceutical ingredient known as CTP-499, which incorporates heavy water as the source of deuterium to achieve the hydrogen...

  16. Accident analysis of heavy water cooled thorium breeder reactor

    Science.gov (United States)

    Yulianti, Yanti; Su'ud, Zaki; Takaki, Naoyuki

    2015-04-01

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of fuel and claddings during accident are still below limitations which are in secure condition.

  17. Enrichment of heavy metals in the inner shelf mud of the East China Sea and its indication to human activity

    Science.gov (United States)

    Chen, Bin; Fan, Dejiang; Li, Weiran; Wang, Liang; Zhang, Xilin; Liu, Ming; Guo, Zhigang

    2014-11-01

    The Yangtze River Basin, which has a population of 0.4 billion and an economic output accounting for 50% of China's Gross Domestic Product (GDP), is one of the most developed regions in China. With dramatic developments in the economy, large quantities of pollutants have entered the Yangtze River and have eventually been discharged into the East China Sea (ECS), and then most of them were preserved in the inner shelf coastal mud areas of the ECS. The inner shelf costal mud areas of the ECS, with sedimentation rate ranging from 0.8 cm/a to 1.2 cm/a, are an ideal place to obtain the high-resolution heavy metal record. In this work, two sediment cores collected in the inner shelf of the coastal mud areas of the ECS in 2009 were used to reconstruct historical records of anthropogenic heavy metal input from the Yangtze River Basin. The temporal distribution of enrichment factors (EFs) is in good accordance with social development of Yangtze River Basin. Before the 1930s, the EFs of Pb and Zn are considered as the background level of study area, according to the agricultural country of China in that time. The much higher EFs of Pb and Zn from the 1930s to 1980s were associated with significant improvement of industry of the Yangtze River Basin. After 1983, the dramatical incensement of EFs of Pb and Zn responded to the remarkable economic development of the Yangtze River Basin. Of particular interest, the construction of the Three Gorges Dam (TGD) in 2003 possibly induced a significant increase in the heavy metal levels in the coastal ECS, and the ban on leaded gasoline in China induced a remarkable decrease in Pb levels. Although heavy metal levels have increased since the 1930s, the coastal mud area of the ECS remains under low ecological risk.

  18. DEGRADATION EVALUATION OF HEAVY WATER DRUMS AND TANKS

    Energy Technology Data Exchange (ETDEWEB)

    Mickalonis, J.; Vormelker, P.

    2009-07-31

    Heavy water with varying chemistries is currently being stored in over 6700 drums in L- and K-areas and in seven tanks in L-, K-, and C-areas. A detailed evaluation of the potential degradation of the drums and tanks, specific to their design and service conditions, has been performed to support the demonstration of their integrity throughout the desired storage period. The 55-gallon drums are of several designs with Type 304 stainless steel as the material of construction. The tanks have capacities ranging from 8000 to 45600 gallons and are made of Type 304 stainless steel. The drums and tanks were designed and fabricated to national regulations, codes and standards per procurement specifications for the Savannah River Site. The drums have had approximately 25 leakage failures over their 50+ years of use with the last drum failure occurring in 2003. The tanks have experienced no leaks to date. The failures in the drums have occurred principally near the bottom weld, which attaches the bottom to the drum sidewall. Failures have occurred by pitting, crevice and stress corrosion cracking and are attributable, in part, to the presence of chloride ions in the heavy water. Probable degradation mechanisms for the continued storage of heavy water were evaluated that could lead to future failures in the drum or tanks. This evaluation will be used to support establishment of an inspection plan which will include susceptible locations, methods, and frequencies for the drums and tanks to avoid future leakage failures.

  19. The Battle for Heavy Water Three physicists' heroic exploits

    CERN Multimedia

    2002-01-01

    Up until the end of the 1970s you could still catch a glimpse of his massive silhouette in the corridors of CERN. Lew Kowarksi, one of the pioneers of the Laboratory, was not only a great physicist; he was also a genuine hero of World War II. In 1940, along with Frédéric Joliot and Hans von Halban, Lew Kowarski managed to get the entire world supply of heavy water away to safety from the Nazis after a fantastic escape from occupied France. At the end of the war, the three physicists played themselves in a film about their adventures entitled 'la Bataille de l'eau lourde'. This film, which has been loaned to us by the French National Film Library, will be shown at CERN for the first time next Thursday. At the beginning of the war, heavy water (D20, two atoms of deuterium and one oxygen atom) was of strategic importance. In 1939 Frédéric Joliot, aided by Hans von Halban and Lew Kowarski, demonstrated the nuclear chain reaction and the moderator role that heavy water plays in it. A few weeks before the inv...

  20. Neutron scattering of a floating heavy water bridge

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Elmar C [Wetsus, Center of Excellence for Sustainable Water Technology, Agora 1, 8900 CC Leeuwarden (Netherlands); Bitschnau, Brigitte [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Rechbauerstrasse 12, 8010 Graz (Austria); Woisetschlaeger, Jakob [Institute of Thermal Turbomachnery and Machine Dynamics, Graz University of Technology, Inffeldgasse 25A, Graz (Austria); Maier, Eugen [Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 16, 8010 Graz (Austria); Beuneu, Brigitte; Teixeira, Jose [Laboratoire Leon Brillouin, CEA-CNRS/IRAMIS, CEA/Saclay, 91191 Gif-sur-Yvette Cedex (France)

    2009-03-21

    When high voltage is applied to distilled water filled into two beakers close to each other, a water connection forms spontaneously, giving the impression of a floating water bridge (Fuchs et al 2007 J. Phys. D: Appl. Phys. 40 6112-4, 2008 J. Phys. D: Appl. Phys. 41 185502). This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. In this work, the first data on neutron scattering of a floating heavy water bridge are presented and possible interpretations are discussed. D{sub 2}O was measured instead of H{sub 2}O because of the very strong incoherent scattering of H. The obtained data support the 'bubble hypothesis' suggested earlier (Fuchs et al 2008).

  1. Heavy metal ions adsorption from mine waters by sawdust

    OpenAIRE

    G. Bogdanović; Milan Gorgievski; Dragana Božić; Velizar Stanković

    2009-01-01

    In this work the results on the batch and column adsorption of copper and some associated ions by employing linden and poplar sawdust as a low-cost adsorbent are presented. The mine water from a local abandoned copper mine, as well as synthetic solutions of those ions which are the main constituents of the mine water were both used as a model-system in this study. The adsorption ability of the chosen sawdust to adsorb heavy metal ions is considered as a function of the initial pH of the solut...

  2. Heavy Water Components Test Reactor Decommissioning - Major Component Removal

    Energy Technology Data Exchange (ETDEWEB)

    Austin, W.; Brinkley, D.

    2010-05-05

    The Heavy Water Components Test Reactor (HWCTR) facility (Figure 1) was built in 1961, operated from 1962 to 1964, and is located in the northwest quadrant of the Savannah River Site (SRS) approximately three miles from the site boundary. The HWCTR facility is on high, well-drained ground, about 30 meters above the water table. The HWCTR was a pressurized heavy water test reactor used to develop candidate fuel designs for heavy water power reactors. It was not a defense-related facility like the materials production reactors at SRS. The reactor was moderated with heavy water and was rated at 50 megawatts thermal power. In December of 1964, operations were terminated and the facility was placed in a standby condition as a result of the decision by the U.S. Atomic Energy Commission to redirect research and development work on heavy water power reactors to reactors cooled with organic materials. For about one year, site personnel maintained the facility in a standby status, and then retired the reactor in place. In 1965, fuel assemblies were removed, systems that contained heavy water were drained, fluid piping systems were drained, deenergized and disconnected and the spent fuel basin was drained and dried. The doors of the reactor facility were shut and it wasn't until 10 years later that decommissioning plans were considered and ultimately postponed due to budget constraints. In the early 1990s, DOE began planning to decommission HWCTR again. Yet, in the face of new budget constraints, DOE deferred dismantlement and placed HWCTR in an extended surveillance and maintenance mode. The doors of the reactor facility were welded shut to protect workers and discourage intruders. The $1.6 billion allocation from the American Recovery and Reinvestment Act to SRS for site clean up at SRS has opened the doors to the HWCTR again - this time for final decommissioning. During the lifetime of HWCTR, 36 different fuel assemblies were tested in the facility. Ten of these

  3. Anthropogenic Enrichment of Heavy Metals in Urban Dust and Possible Corresponding Sources

    Science.gov (United States)

    van Laaten, Neele; Merten, Dirk; Pirrung, Michael

    2017-04-01

    Atmospheric dust (particulate matter, PM) is regarded as a crucial factor for human health and a major environmental problem in densely populated areas. Due to anthropogenic processes like traffic, waste incineration and industry increased amounts of PM can be detected in those areas. To reduce the amounts detailed knowledge on both the composition of PM and the source contribution in a target area is needed. The latter has, to our knowledge, rarely been regarded in central Europe. Within this study, spider webs from various locations in the city of Jena (Germany), that act as natural trappers of PM, were analyzed for the contents of 27 trace elements using aqua regia digestion followed by ICP-OES and ICP-MS determinations. Aerosol-crust enrichment factors were calculated for selected elements and both a cluster analysis and a factor analysis were executed to identify sources of PM. High values for the enrichment factors clearly show an anthropogenic influence. In addition, the cluster analysis leads to a grouping of the sampling points mainly depending on the kind and volume of traffic at the corresponding locations. Five different possible sources of PM can be found by the factor analysis: Soil erosion (41% of variance), abrasion of rails (16%), tyre and break wear (16%), charcoal combustion (8%) and oil combustion (7%).

  4. Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Shakhawat, E-mail: Schowdhury@kfupm.edu.sa [Department of Civil and Environmental Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Mazumder, M.A. Jafar [Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Al-Attas, Omar [Department of Civil and Environmental Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Husain, Tahir [Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John’s, NL (Canada)

    2016-11-01

    Heavy metals in drinking water pose a threat to human health. Populations are exposed to heavy metals primarily through water consumption, but few heavy metals can bioaccumulate in the human body (e.g., in lipids and the gastrointestinal system) and may induce cancer and other risks. To date, few thousand publications have reported various aspects of heavy metals in drinking water, including the types and quantities of metals in drinking water, their sources, factors affecting their concentrations at exposure points, human exposure, potential risks, and their removal from drinking water. Many developing countries are faced with the challenge of reducing human exposure to heavy metals, mainly due to their limited economic capacities to use advanced technologies for heavy metal removal. This paper aims to review the state of research on heavy metals in drinking water in developing countries; understand their types and variability, sources, exposure, possible health effects, and removal; and analyze the factors contributing to heavy metals in drinking water. This study identifies the current challenges in developing countries, and future research needs to reduce the levels of heavy metals in drinking water. - Highlights: • Co-exposure to multiple heavy metals in drinking water needs better understanding • Low-cost technologies for arsenic removal needs urgent attention • Protonated alginate needs further research for drinking water applications • Community level and PoU devices need improvement and cost reduction • Developing countries are most affected by heavy metals in drinking water.

  5. Uptake of heavy metals and arsenic in black soldier fly (Hermetia illucens) larvae grown on seaweed-enriched media.

    Science.gov (United States)

    Biancarosa, Irene; Liland, Nina S; Biemans, Daan; Araujo, Pedro; Bruckner, Christian G; Waagbø, Rune; Torstensen, Bente E; Lock, Erik-Jan; Amlund, Heidi

    2017-09-27

    The black soldier fly (Hermetia illucens) is one of the most promising insect species for use in animal feed. However, studies investigating feed and food safety aspects of using black soldier fly as feed are scarce. In this study, we fed black soldier fly larvae feeding media enriched with seaweed, which contains naturally high concentrations of heavy metals and arsenic. The aim of this study was to investigate the potential transfer of such undesirable substances from the feeding media to the larvae. The larvae accumulated cadmium, lead, mercury and arsenic. Concentrations of these elements in the larvae increased when more seaweed was added to the feeding media. The highest retention was seen for cadmium (up to 93%) and the lowest for total arsenic (up to 22%). When seaweed inclusion exceeded 20% in the media, this resulted in larval concentrations of cadmium and total arsenic above the current European Union maximum levels for these elements in complete feed. Our results confirm that insect larvae can accumulate heavy metals and arsenic when present in the feeding media. A broader understanding of the occurrence of these undesirable substances in processed larvae products is needed to assess feed and food safety. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. Influence of enriched soaking water on shiitake (Lentinus edodes (Berk. Singer mushroom yield and properties

    Directory of Open Access Journals (Sweden)

    Mohammad Ebrahim RANJBAR

    2017-12-01

    Full Text Available Shiitake is an edible mushroom native to East Asia. In the present research, the soaking water was targeted as the vehicle to enrich the substrate. The amount of nutrients in the substrate is severely reduced by mycelium growth and development during spawn running and browning period. Some part of this reduction can be compensated by soaking the substrate in the enriched soaking water. In this study, soaking water was enriched by some complement materials and enrichment effects on some important properties of shiitake mushroom were evaluated. The highest biological efficiency (69.88 % was gained with soaking the blocks in wheat bran extraction suspension. The highest dry matter of mushroom was obtained by rice bran extraction suspension as the enriched soaking water. The results of this research showed that some important properties of shiitake mushroom can be improved by soaking the blocks with enriched soaking water. According to the results, wheat bran extraction suspension was the best enriched solution to increase productivity of shiitake mushrooms and rice bran extraction suspension was suitable to improve quality of mushrooms.

  7. Critical heat flux experiments in a circular tube with heavy water and light water. (AWBA Development Program)

    Energy Technology Data Exchange (ETDEWEB)

    Williams, C.L.; Beus, S.G.

    1980-05-01

    Experiments were performed to establish the critical heat flux (CHF) characteristics of heavy water and light water. Testing was performed with the up-flow of heavy and of light water within a 0.3744 inch inside diameter circular tube with 72.3 inches of heated length. Comparisons were made between heavy water and light water critical heat flux levels for the same local equilibrium quality at CHF, operating pressure, and nominal mass velocity. Results showed that heavy water CHF values were, on the average, 8 percent below the light water CHF values.

  8. Physiological and Metagenomic Analyses of Microbial Mats Involved in Self-Purification of Mine Waters Contaminated with Heavy Metals

    Science.gov (United States)

    Drewniak, Lukasz; Krawczyk, Pawel S.; Mielnicki, Sebastian; Adamska, Dorota; Sobczak, Adam; Lipinski, Leszek; Burec-Drewniak, Weronika; Sklodowska, Aleksandra

    2016-01-01

    Two microbial mats found inside two old (gold and uranium) mines in Zloty Stok and Kowary located in SW Poland seem to form a natural barrier that traps heavy metals leaking from dewatering systems. We performed complex physiological and metagenomic analyses to determine which microorganisms are the main driving agents responsible for self-purification of the mine waters and identify metabolic processes responsible for the observed features. SEM and energy dispersive X-ray microanalysis showed accumulation of heavy metals on the mat surface, whereas, sorption experiments showed that neither microbial mats were completely saturated with heavy metals present in the mine waters, indicating that they have a large potential to absorb significant quantities of metal. The metagenomic analysis revealed that Methylococcaceae and Methylophilaceae families were the most abundant in both communities, moreover, it strongly suggest that backbones of both mats were formed by filamentous bacteria, such as Leptothrix, Thiothrix, and Beggiatoa. The Kowary bacterial community was enriched with the Helicobacteraceae family, whereas the Zloty Stok community consist mainly of Sphingomonadaceae, Rhodobacteraceae, and Caulobacteraceae families. Functional (culture-based) and metagenome (sequence-based) analyses showed that bacteria involved in immobilization of heavy metals, rather than those engaged in mobilization, were the main driving force within the analyzed communities. In turn, a comparison of functional genes revealed that the biofilm formation and heavy metal resistance (HMR) functions are more desirable in microorganisms engaged in water purification than the ability to utilize heavy metals in the respiratory process (oxidation-reduction). These findings provide insight on the activity of bacteria leading, from biofilm formation to self-purification, of mine waters contaminated with heavy metals. PMID:27559332

  9. Water enriched in the rare stable isotopes : Preparation, measurement and applications

    NARCIS (Netherlands)

    Faghihi, Vahideh

    2016-01-01

    The subject of this thesis is water with increased abundances of the rare stable isotopes 2H and 18O (and to some extent also 17O). Such artificially enriched (or "labelled") waters are often used in biomedicine, for establishing the total amount of body water (and thus body composition) of humans

  10. Meta-Analysis of the Copper, Zinc, and Cadmium Absorption Capacities of Aquatic Plants in Heavy Metal-Polluted Water.

    Science.gov (United States)

    Li, Jing; Yu, Haixin; Luan, Yaning

    2015-11-26

    The use of aquatic plants for phytoremediation is an important method for restoring polluted ecosystems. We sought to analyze the capacity of different aquatic plant species to absorb heavy metals and to summarize available relevant scientific data on this topic. We present a meta-analysis of Cu, Zn, and Cd absorption capacities of aquatic plants to provide a scientific basis for the selection of aquatic plants suitable for remediation of heavy-metal pollution. Plants from the Gramineae, Pontederiaceae, Ceratophyllaceae, Typhaceae and Haloragaceae showed relatively strong abilities to absorb these metals. The ability of a particular plant species to absorb a given metal was strongly correlated with its ability to absorb the other metals. However, the absorption abilities varied with the plant organ, with the following trend: roots > stems > leaves. The pH of the water and the life habits of aquatic plants (submerged and emerged) also affect the plant's ability to absorb elements. Acidic water aids the uptake of heavy metals by plants. The correlation observed between element concentrations in plants with different aquatic life habits suggested that the enrichment mechanism is related to the surface area of the plant exposed to water. We argue that this meta-analysis would aid the selection of aquatic plants suitable for heavy-metal absorption from polluted waters.

  11. Ecological risk of heavy metals in sediments of the luan river source water

    Science.gov (United States)

    Liu, J.; Li, Y.; Zhang, B.; Cao, J.; Cao, Z.; Domagalski, Joseph L.

    2009-01-01

    Distribution and characteristics of heavy metals enrichment in sediment were surveyed including the bio-available form analyzed for assessment of the Luan River source water quality. The approaches of sediment quality guidelines (SQG), risk assessment code and Hakanson potential ecological risk index were used for the ecological risk assessment. According to SQG, The results show that in animal bodies, Hg at the sampling site of Wuliehexia was 1.39 mg/kg, Cr at Sandaohezi was 152.37 mg/kg and Cu at Hanjiaying was 178.61 mg/kg exceeding the severe effect screening level. There were 90% of sampling sites of Cr and Pb and 50% sites of Cu exceeded the lowest effect screening level. At Boluonuo and Wuliehexia, the exchangeable and carbonate fractions for above 50% of sites were at high risk levels and that for above 30% of sites at Xiahenan and Wulieheshang were also at high risk levels. Other sites were at medium risk level. Compared to soil background values of China, Hg and Cd showed very strong ecological risk, and the seven heavy metals of Hg, Cd, Cu, As, Pb, Cr, Zn at ecological risk levels were in the descending order. The results could give insight into risk assessment of environmental pollution and decision-making for water source security. ?? 2009 Springer Science+Business Media, LLC.

  12. An Assessment Of Physicochemical Properties, Heavy Metal Enrichment And Fungal Characterization Of Refined Kerosene Impacted Soil In Anand, Gujarat, India

    Directory of Open Access Journals (Sweden)

    Shamiyan R Khan

    2013-12-01

    Full Text Available The present study was carried out to assess the physico-chemical properties, heavy metal enrichment and fungal isolation and characterization of the top soil samples collected in-situ from aged refined kerosene contaminated as well as uncontaminated garden soil sites in Anand, Gujarat, India. The total petroleum hydrocarbon (TPH concentrations were 17,510 mg/kg in kerosene contaminated soil against 142.65 mg/kg for uncontaminated soils. The contamination increased the soil organic carbon, nitrogen and clay to 2.95 %, 0.612 %, 36.22 % as compared to 1.5%, 0.153%, 32.4% respectively in the uncontaminated soil. Increased concentration of heavy metals like Cobalt, Copper, Iron, Zinc and Lead against the uncontaminated soil was encountered. Ten native fungal speciesbelonging to a total of five genera include Aspergillus (A. terreus, A. versicolor, A. niger; Fusarium oxysporum; Penicilliumjanthinellum from the uncontaminated garden soil, whereas the contaminated soil included Aspergillus (A. terreus, A. versicolor , A. niger Candida tropicalis,Cladosporiumbruhnei and Fusarium oxysporum, identified based on 18S rRNA and the nucleotide sequences were submitted to the NCBI, GenBank database. The changes created by kerosene contamination resulted in variation in individual concentrations of physicochemical properties, soil conductivity, pH and soil fertility indices probably dwindle the growth of fungal strains causing a reduction in the fungal population in the kerosene contaminated soil. International Journal of Environment, Volume-2, Issue-1, Sep-Nov 2013, Pages 164-174 DOI: http://dx.doi.org/10.3126/ije.v2i1.9219

  13. Competitive sorption of heavy metals by water hyacinth roots.

    Science.gov (United States)

    Zheng, Jia-Chuan; Liu, Hou-Qi; Feng, Hui-Min; Li, Wen-Wei; Lam, Michael Hon-Wah; Lam, Paul Kwan-Sing; Yu, Han-Qing

    2016-12-01

    Heavy metal pollution is a global issue severely constraining aquaculture practices, not only deteriorating the aquatic environment but also threatening the aquaculture production. One promising solution is adopting aquaponics systems where a synergy can be established between aquaculture and aquatic plants for metal sorption, but the interactions of multiple metals in such aquatic plants are poorly understood. In this study, we investigated the absorption behaviors of Cu(II) and Cd(II) in water by water hyacinth roots in both single- and binary-metal systems. Cu(II) and Cd(II) were individually removed by water hyacinth roots at high efficiency, accompanied with release of protons and cations such as Ca 2+ and Mg 2+ . However, in a binary-metal arrangement, the Cd(II) sorption was significantly inhibited by Cu(II), and the higher sorption affinity of Cu(II) accounted for its competitive sorption advantage. Ionic exchange was identified as a predominant mechanism of the metal sorption by water hyacinth roots, and the amine and oxygen-containing groups are the main binding sites accounting for metal sorption via chelation or coordination. This study highlights the interactive impacts of different metals during their sorption by water hyacinth roots and elucidates the underlying mechanism of metal competitive sorption, which may provide useful implications for optimization of phytoremediation system and development of more sustainable aquaculture industry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Leaching of Heavy Metals from Water Bottle Components into the Drinking Water of Rodents

    Science.gov (United States)

    Nunamaker, Elizabeth A; Otto, Kevin J; Artwohl, James E; Fortman, Jeffrey D

    2013-01-01

    Providing high-quality, uncontaminated drinking water is an essential component of rodent husbandry. Acidification of drinking water is a common technique to control microbial growth but is not a benign treatment. In addition to its potential biologic effects, acidified water might interact with the water-delivery system, leading to the leaching of heavy metals into the drinking water. The goal of the current study was to evaluate the effects of water acidification and autoclaving on water-bottle assemblies. The individual components of the system (stainless-steel sipper tubes, rubber stoppers, neoprene stoppers, and polysulfone water bottles) were acid-digested and analyzed for cadmium, chromium, copper, iron, lead, magnesium, manganese, selenium, and zinc to quantify the metal composition of each material. In addition the amounts of these metals that leached into tap and acidified water with and without autoclaving were quantified after 1 wk of contact time. On a weight basis, sipper tubes contained the largest quantities of all metals except magnesium and zinc, which were greatest in the neoprene stoppers. Except for cadmium and selenium, all metals had leached into the water after 1 wk, especially under the acidified condition. The quantities of copper, lead, and zinc that leached into the drinking water were the most noteworthy, because the resulting concentrations had the potential to confound animal experiments. On the basis of these findings, we suggest that water-quality monitoring programs include heavy metal analysis at the level of water delivery to animals. PMID:23562029

  15. Nutrient and Organic Carbon Losses, Enrichment Rate, and Cost of Water Erosion

    OpenAIRE

    Ildegardis Bertol; Rodrigo Vieira Luciano; Camilo Bertol; Bárbara Bagio

    2017-01-01

    ABSTRACT Soil erosion from water causes loss of nutrients and organic carbon, enriches the environment outside the erosion site, and results in costs. The no-tillage system generates increased nutrient and C content in the topsoil and, although it controls erosion, it can produce a more enriched runoff than in the conventional tillage system. This study was conducted in a Humic Cambisol in natural rainfall from 1997 to 2012 to quantify the contents and total losses of nutrients and organic C ...

  16. Stable isotope ratio measurements on highly enriched water samples by means of laser spectrometry

    NARCIS (Netherlands)

    van Trigt, R; Kerstel, E.R.T.; Visser, GH; Meijer, H.A.J.

    2001-01-01

    We demonstrate the feasibility of using laser spectrometry (LS) to analyze isotopically highly enriched water samples (i.e., delta H-2 less than or equal to 15000 parts per thousand, delta O-18 less than or equal to 1200 parts per thousand), as often used in the biomedical doubly labeled water (DLW)

  17. The measurement of tritium in water samples with electrolytic enrichment using liquid scintillation counter

    Directory of Open Access Journals (Sweden)

    Janković Marija M.

    2012-01-01

    Full Text Available Tritium (3H present in the environment decreased in the last decades and nowadays it has low activity concentrations. Measurement of low-level tritium activities in natural waters, e. g. in precipitation, groundwater, and river water requires special techniques for water pretreatment and detection of low-level radioactivity. In order to increase the tritium concentration to an easily measurable level, electrolytic enrichment must be applied. This paper presents the enrichment method performed by electrolysis in a battery of 18 cells, giving an enrichment factor of 5.84 (calculated from 59 electrolyses. The calculated mean values of the separation factor and enrichment parameter were 4.10 and 0.84, respectively. Results for tritium activity in precipitation and surface water collected in Belgrade during 2008 and 2009 are presented. The Radiation and Environmental Protection Department of the Vinča Institute of Nuclear Sciences, participated in the IAEA TRIC2008 international intercomparison exercise. The participation in the intercomparisons for any laboratory doing low-level 3H measurements in the waters is very important and useful. It is considered the best way to check the entire procedure and methods of the measurements and the reliability of the standard used. The analysis of the reported 3H activity results showed that all results for five intercomparison samples, for which electrolytic enrichment were applied prior to the 3H measurement, are acceptable.

  18. Spatial variation of deuterium enrichment in bulk water of snowgum leaves.

    Science.gov (United States)

    Santrucek, Jirí; Kveton, Jirí; Setlík, Jirí; Bulícková, Lenka

    2007-01-01

    Deuterium enrichment of bulk water was measured and modeled in snowgum (Eucalyptus pauciflora Sieber ex Sprengel) leaves grown under contrasting air and soil humidity in arid and wet conditions in a glasshouse. A map of the enrichment was constructed with a resolution of 4 mm by using a newly designed cryodistillation method. There was progressively increasing enrichment in both longitudinal (along the leaf midrib) and transversal (perpendicular to the midrib) directions, most pronounced in the arid-grown leaf. The whole-leaf average of the enrichment was well below the value estimated by the Craig-Gordon model. The discrepancy between model and measurements persisted when the estimates were carried out separately for the leaf base and tip, which differed in temperature and stomatal conductance. The discrepancy was proportional to the transpiration rate, indicating the significance of diffusion-advection interplay (Péclet effect) of deuterium-containing water molecules in small veins close to the evaporating sites in the leaf. Combined Craig-Gordon and desert-river models, with or without the Péclet number, P, were used for predicting the leaf longitudinal enrichment. The predictions without P overestimated the measured values of deltadeuterium. Fixed P value partially improved the coincidence. We suggest that P should vary along the leaf length l to reconcile the modeled data with observations of longitudinal enrichment. Local values of P, P(l), integrating the upstream fraction of water used or the leaf area, substantially improved the model predictions.

  19. Spatial Variation of Deuterium Enrichment in Bulk Water of Snowgum Leaves1[OA

    Science.gov (United States)

    Šantrůček, Jiří; Květoň, Jiří; Šetlík, Jiří; Bulíčková, Lenka

    2007-01-01

    Deuterium enrichment of bulk water was measured and modeled in snowgum (Eucalyptus pauciflora Sieber ex Sprengel) leaves grown under contrasting air and soil humidity in arid and wet conditions in a glasshouse. A map of the enrichment was constructed with a resolution of 4 mm by using a newly designed cryodistillation method. There was progressively increasing enrichment in both longitudinal (along the leaf midrib) and transversal (perpendicular to the midrib) directions, most pronounced in the arid-grown leaf. The whole-leaf average of the enrichment was well below the value estimated by the Craig-Gordon model. The discrepancy between model and measurements persisted when the estimates were carried out separately for the leaf base and tip, which differed in temperature and stomatal conductance. The discrepancy was proportional to the transpiration rate, indicating the significance of diffusion-advection interplay (Péclet effect) of deuterium-containing water molecules in small veins close to the evaporating sites in the leaf. Combined Craig-Gordon and desert-river models, with or without the Péclet number, P, were used for predicting the leaf longitudinal enrichment. The predictions without P overestimated the measured values of δdeuterium. Fixed P value partially improved the coincidence. We suggest that P should vary along the leaf length l to reconcile the modeled data with observations of longitudinal enrichment. Local values of P, P(l), integrating the upstream fraction of water used or the leaf area, substantially improved the model predictions. PMID:17158587

  20. Treatment of Arsenazo III contaminated heavy water stored at Darlington

    Energy Technology Data Exchange (ETDEWEB)

    Suryanarayan, S.; Husain, A., E-mail: sriram.s@kinectrics.com [Kinectrics Inc., Toronto, Ontario (Canada); Williams, D., E-mail: denny.williams@opg.com [Ontario Power Generation, Darlington Nuclear Generating Station, Bowmanville, Ontario (Canada)

    2010-07-01

    Darlington Nuclear Generating Station (DNGS) has accumulated over 48 drums of chemistry laboratory waste arising from analysis of heavy water (D{sub 2}O). Several organic, including Arsenazo III, and inorganic contaminants present in these drums results in high total organic carbon (TOC) and conductivity. These drums have not been processed due to uncertainties related to clean-up of Arsenazo III contaminated heavy water. This paper provides details of chemical characterization as well as bench scale studies performed to demonstrate the feasibility of treating the downgraded D{sub 2}O to the stringent target specifications of <1 ppm TOC and <0.1mS/m conductivity, required for feed to the Station Upgrading Plant (SUP). Both ionic organic species such as glycolate, acetate and formate as well as neutral organics such as acetone, methanol and ethylene glycol were detected in all the samples. Morpholine and propylene glycol were detected in one sample. Arsenazo III was determined to be not a major contaminant (maximum 8.4 ppm) in these waste drums, compared to the other organic contaminants present. Various unit processes such as pH adjustment, granular activated carbon (GAC), ion exchange resin (IX), UV-peroxide oxidation (UV-H{sub 2}O{sub 2}) treatments, nanofiltration (NF) as well as reverse osmosis (RO) were tested on a bench scale both singly as well as in various combinations to evaluate their ability to achieve the stringent target conductivity and TOC specifications. Among the various bench scale tests evaluated, the successive processing train used at DNGS and consisting of GAC+IX+UV/H{sub 2}O{sub 2}+IX (polishing) unit operations was found to meet target specifications for both conductivity and TOC. Unit processes comprising (GAC+IX) and (RO-double pass + GAC+IX) met conductivity targets but failed to meet TOC specifications. The results of GAC+IX tests clearly emphasize the importance of using low flow rates for successful reduction in both conductivity as

  1. A pre-enrichment step is essential for detection of Campylobacter sp. in turbid pond water.

    Science.gov (United States)

    Abulreesh, H H; Paget, T A; Goulder, R

    2014-06-01

    This work aimed to detect Campylobacter species from naturally contaminated turbid pond water by PCR. A total of 16 water samples were collected from a turbid village pond. Four methods of DNA extraction were applied to centrifuge pellets from eight 100 ml pond water samples prior to attempted detection of Campylobacter by PCR without an enrichment step. These methods were (1) Tris-HCl and sodium dodecyl sulfate followed by phenol:chloroform:isoamylalcohol extraction followed by treatment with DNA clean up kit, (2) proteinase K, (3) Chelex® 100, and (4) boiling. The other eight pond water samples (10 ml and 100 ml) were filtered and filters were incubated overnight in Preston enrichment broth. The centrifuge pellets obtained from enrichment cultures were treated by proteinase K for DNA extraction. Primers CF03 and CF04 for the flagellin genes (flaA and flaB) of Campylobacter jejuni and Campylobacter coli were used for amplifying the extracted DNA. The DNA extracted from eight-100 ml pond water samples that were not subject to selective enrichment was never amplified with primers CF03 and CF04, hence Campylobacter was not detected. In contrast, the DNA that was from samples that were subjected to a selective enrichment step in Preston broth prior to PCR assay always gave amplified bands of 340-380 bp, therefore the presence of Campylobacter was confirmed. Detection of campylobacters from naturally contaminated, turbid, environmental water may not be feasible by direct PCR assay because of low numbers and the presence of high concentration of humic matter and other PCR inhibitors. The enrichment of water samples in selective broth, however, facilitated PCR detection of Campylobacter probably by increasing cell number and by diluting PCR inhibitors.

  2. Pollution status of Pakistan: a retrospective review on heavy metal contamination of water, soil, and vegetables.

    Science.gov (United States)

    Waseem, Amir; Arshad, Jahanzaib; Iqbal, Farhat; Sajjad, Ashif; Mehmood, Zahid; Murtaza, Ghulam

    2014-01-01

    Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food chain which especially can be highly dangerous to human health. This study reviews the heavy metal contamination in several areas of Pakistan over the past few years, particularly to assess the heavy metal contamination in water (ground water, surface water, and waste water), soil, sediments, particulate matter, and vegetables. The listed contaminations affect the drinking water quality, ecological environment, and food chain. Moreover, the toxicity induced by contaminated water, soil, and vegetables poses serious threat to human health.

  3. Pollution Status of Pakistan: A Retrospective Review on Heavy Metal Contamination of Water, Soil, and Vegetables

    Directory of Open Access Journals (Sweden)

    Amir Waseem

    2014-01-01

    Full Text Available Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food chain which especially can be highly dangerous to human health. This study reviews the heavy metal contamination in several areas of Pakistan over the past few years, particularly to assess the heavy metal contamination in water (ground water, surface water, and waste water, soil, sediments, particulate matter, and vegetables. The listed contaminations affect the drinking water quality, ecological environment, and food chain. Moreover, the toxicity induced by contaminated water, soil, and vegetables poses serious threat to human health.

  4. Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.

    Science.gov (United States)

    Chowdhury, Shakhawat; Mazumder, M A Jafar; Al-Attas, Omar; Husain, Tahir

    2016-11-01

    Heavy metals in drinking water pose a threat to human health. Populations are exposed to heavy metals primarily through water consumption, but few heavy metals can bioaccumulate in the human body (e.g., in lipids and the gastrointestinal system) and may induce cancer and other risks. To date, few thousand publications have reported various aspects of heavy metals in drinking water, including the types and quantities of metals in drinking water, their sources, factors affecting their concentrations at exposure points, human exposure, potential risks, and their removal from drinking water. Many developing countries are faced with the challenge of reducing human exposure to heavy metals, mainly due to their limited economic capacities to use advanced technologies for heavy metal removal. This paper aims to review the state of research on heavy metals in drinking water in developing countries; understand their types and variability, sources, exposure, possible health effects, and removal; and analyze the factors contributing to heavy metals in drinking water. This study identifies the current challenges in developing countries, and future research needs to reduce the levels of heavy metals in drinking water. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Assessment of heavy metals contamination in the Nile River water and adjacent sediments: A case study from Khartoum City and Nile River State, Sudan

    Directory of Open Access Journals (Sweden)

    Magboul M. Sulieman

    2017-07-01

    Full Text Available The current study aims to investigate the heavy metals concentration and the degree of pollution in the water and adjacent sediment of the Nile River and its main tributaries at Khartoum City and River Nile State, Sudan. For this purpose, thirty-three water and sediment samples were collected from River Nile, Blue Nile, and White Nile. Water chemical properties and sediment physicо-chemical properties were measure. Concentrations of heavy metals (As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Ti, Zn were determined for both sediment and water samples using inductively coupled plasma (ICP-OES. Enrichment factor (EF and geo-accumulation index (Igeo were applied to quantify heavy metals pollution levels in sediment samples. The revealed that only Fe metal detected in the water samples and its concentrations within the permissible maximum limit. This indicated that water is highly suitable for irrigation. Depending on calculated enrichment factor (EF and geo-accumulation index (Igeo, sediment samples were found to be enriched and polluted with Mn and Mo particularly at Berber site which may as consequence of gold mining activities in this area. The study revealed relatively strong to strong correlation between heavy metals of Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, Zn (r2=0.84 to 0.99 and significant negative correlation with Mo (r2=0.58 to 0.73. This study recommends regular monitoring of heavy metals in the Nile River and its main tributaries for conservation and protection from pollution.

  6. Removal of Heavy Metals from Drinking Water by Magnetic Carbon Nanostructures Prepared from Biomass

    OpenAIRE

    Muhammad Muneeb Ur Rahman Khattak; Muhammad Zahoor; Bakhtiar Muhammad; Farhat Ali Khan; Riaz Ullah; AbdEI-Salam, Naser M.

    2017-01-01

    Heavy metals contamination of drinking water has significant adverse effects on human health due to their toxic nature. In this study a new adsorbent, magnetic graphitic nanostructures were prepared from watermelon waste. The adsorbent was characterized by different instrumental techniques (surface area analyzer, FTIR, XRD, EDX, SEM, and TG/DTA) and was used for the removal of heavy metals (As, Cr, Cu, Pb, and Zn) from water. The adsorption parameters were determined for heavy metals adsorpti...

  7. HEAVY METAL CONTAMINATION OF WATER IN NEGOMBO LAGOON AND INTERCONNECTED WATER SOURCES

    Directory of Open Access Journals (Sweden)

    C.M. Kanchana.N.K.CHANDRASEKARA

    2014-12-01

    Full Text Available Water quality in natural lagoons that are located within close proximity to human settlements is generally at contamination risk due to increasing anthropogenic activities. The Negombo lagoon situated in the Gampaha District in Sri Lanka is a lagoonal estuary. It receives surface water runoff mainly from Dandugamoya, Ja-ela, Hamilton and Dutch canals. During the recent past, it has been noted by several researches that there is increasing evidence in anthropogenic activities in Negombo lagoon and surrounding areas. The present study was carried out to assess the contamination levels of heavy metals of water in the Negombo lagoon and interconnected water sources. Sampling was carried out in 19 locations; 6 in the Negombo lagoon and 13 from the interconnected sources (5 samples from Hamilton canal, 2 samples each from Dutch canal, Dandugamoya and Ja-Ela and one sample each from Kelani estuary and Ocean-Negombo. The data collection was conducted during relatively wet (May and relatively dry (September months in 2013. Water samples were analysed in the laboratory as per the standards methods of American Public Health Association (APHA manual by using the Atomic Absorption Spectrophotometer. The tests were carried out to detect heavy metals: cadmium (Cd, chromium (Cr, copper (Cu, Lead (Pb, manganese (Mn, and zinc (Zn in water. Data analysis was accomplished using ArcGIS (version 9.3 software package along with Microsoft Excel. Standards for inland water and drinking water of Sri Lanka were used to determine the threshold levels of heavy metals. The results show that concentrations of Cr, Cu, Mn and Zn of all water bodies were below the threshold level of human consumption and quality standards for inland waters in Sri Lanka. The Cd and Pb levels of water in Negombo lagoon and Hamilton canal were comparatively high. Furthermore the Cd and Pb levels of Dandugamoya, Ja-ela and Dutch canals were below the maximum permissible levels in both relatively wet

  8. Contribution of Heavy Metal Leaching from Agricultural Soils to Surface Water Loads

    NARCIS (Netherlands)

    Bonten, L.T.C.; Romkens, P.F.A.M.; Brus, D.J.

    2008-01-01

    Point sources for surface water contamination have been reduced by 50 to 90% during the past decades in The Netherlands. However, quality guidelines for heavy metals are still exceeded in many surface waters. It has been suggested that leaching of heavy metals from (diffusively polluted) soils can

  9. Heavy metal contamination of water and fish in peri-urban dams ...

    African Journals Online (AJOL)

    Urban effluents are significant sources of heavy metal pollution in fresh water. Metal contamination in dams around the city of Bulawayo, Zimbabwe, were monitored during October 2014 to assess ecological and public health risks. Heavy metals were measured in water, sediment and fish in dams located downstream of ...

  10. Short-term dynamics of evaporative enrichment of xylem water in woody stems: implications for ecohydrology.

    Science.gov (United States)

    Martín-Gómez, Paula; Serrano, Luis; Ferrio, Juan Pedro

    2017-04-01

    In ecohydrology, it is generally assumed that xylem water reflects the water source used by plants. Several studies have reported isotopic enrichment within woody tissues, particularly during dormancy periods or after long periods of inactivity. However, little is known about the short-term dynamics of this process. Here we assessed the magnitude and dynamics of xylem isotopic enrichment in suberized twigs of pines and oaks. We performed a series of laboratory experiments, in which we monitored hourly changes in water content and isotopic composition under two contrasting scenarios of sap flow restriction. First, we simulated the effect of extreme hydraulic failure by excising twigs to restrict sap flow, while sealing the wounds to ensure that water loss took place only through the leaves or bark, as would be the case for evaporation in attached stems. Second, we studied the effect of reduced leaf transpiration by darkening with aluminium foil all the leaves of healthy, well-watered saplings growing in pot conditions. We found evidence of fast evaporative enrichment in metabolically active stems, as a consequence of a temporal decline in sap flow rates, and not necessarily linked to a traceable decline in stem water content. The excision experiments showed significant isotopic changes (~+1‰ in oxygen) appearing in enrichment of xylem water in stems is a highly dynamic process that may have significant effects even during short periods of restricted water flow. This has important implications for the study of plant water uptake, as well as for ecosystem- and global-scale hydrological models. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Freeze concentration for enrichment of nutrients in yellow water from no-mix toilets.

    Science.gov (United States)

    Gulyas, H; Bruhn, P; Furmanska, M; Hartrampf, K; Kot, K; Lüttenberg, B; Mahmood, Z; Stelmaszewska, K; Otterpohl, R

    2004-01-01

    Separately collected urine ("yellow water") can be utilized as fertilizer. In order to decrease storage volumes and energy consumption for yellow water transport to fields, enrichment of nutrients in yellow water has to be considered. Laboratory-scale batch freeze concentration of yellow water has been tested in ice-front freezing apparatus: a stirred vessel and a falling film freeze concentrator (coolant temperatures: -6 to -16 degrees C). With progressing enrichment of the liquid concentrate, the frozen ice was increasingly contaminated with yellow water constituents (ammonia, total nitrogen, total phosphorus, TOC, and salts determined as conductivity). The higher the initial salinity of the yellow water and the lower the mechanical agitation of the liquid phase contacting the growing ice front, the more the frozen ice was contaminated. The results indicate, that in ice-front freezing devices multistage processes are necessary, i.e. the melted ice phase has to be purified (and the concentrates must be further enriched) in a second or even in a third stage. Energy consumption of this process is very high. However, technical scale suspension freeze concentration is reasonable in centralized ecological sanitation schemes if the population exceeds 0.5 million and distance of yellow water transportation to fields is more than 80 km.

  12. Photochemical fate of beta-blockers in NOM enriched waters.

    Science.gov (United States)

    Wang, Ling; Xu, Haomin; Cooper, William J; Song, Weihua

    2012-06-01

    Beta-blockers, prescribed for the treatment of high blood pressure and for long-term use after a heart attack, have been detected in surface and ground waters. This study examines the photochemical fate of three beta-blockers, atenolol, metoprolol, and nadolol. Hydrolysis accounted for minor losses of these beta-blockers in the pH range 4-10. The rate of direct photolysis at pH 7 in a solar simulator varied from 6.1 to 8.9h(-1) at pH 7. However, the addition of a natural organic matter (NOM) isolate enhanced the photochemical loss of all three compounds. Indirect photochemical fate, generally described by reactions with hydroxyl radical (OH) and singlet oxygen ((1)ΔO(2)), and, the direct reaction with the triplet excited state, (3)NOM(⁎), also varied but collectively appeared to be the major loss factor. Bimolecular reaction rate constants of the three beta-blockers with (1)ΔO(2) and OH were measured and accounted for 0.02-0.04% and 7.2-38.9% of their loss, respectively. These data suggest that the (3)NOM(⁎) contributed 50.6-85.4%. Experiments with various (3)NOM(⁎) quenchers supported the hypothesis that it was singly the most important reaction. Atenolol was chosen for more detailed investigation, with the photoproducts identified by LC-MS analysis. The results suggested that electron-transfer could be an important mechanism in photochemical fate of beta-blockers in the presence of NOM. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Heavy metal incorporation in foraminiferal calcite: results from multi-element enrichment culture experiments with Ammonia tepida

    Directory of Open Access Journals (Sweden)

    G.-J. Reichart

    2010-08-01

    Full Text Available The incorporation of heavy metals into carbonate tests of the shallow water benthic foraminifer Ammonia tepida was investigated under controlled laboratory conditions. Temperature, salinity, and pH of the culture solutions were kept constant throughout the duration of this experiment, while trace metal concentrations were varied. Concentrations of Ni, Cu, and Mn were set 5-, 10-, and 20 times higher than levels found in natural North Sea water; for reference, a control experiment with pure filtered natural North Sea water was also analysed. The concentrations of Cu and Ni from newly grown chambers were determined by means of both μ-synchrotron XRF and Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA-ICP-MS. The results of both independent analytical techniques agreed within the analytical uncertainty. In general, the concentration of the analysed elements in the tests increased in line with their concentration in the culture solutions. Potential toxic and/or chemical competition effects might have resulted in the decreased incorporation of Ni and Cu into the calcite of the specimens exposed to the highest elemental concentrations. Mn incorporation exhibited large variability in the experiment with the 20-fold increased element concentrations, potentially due to antagonistic effects with Cu. The partition coefficients of Cu and Ni were calculated to be 0.14 ± 0.02 and 1.0 ± 0.5, respectively, whereas the partition coefficient of Mn was estimated to be least 2.4. These partition coefficients now open the way for reconstructing past concentrations for these elements in sea water.

  14. Eutrophication and macroalgal blooms in temperate and tropical coastal waters: nutrient enrichment experiments with Ulva spp.

    OpenAIRE

    Teichberg, Mirta; Fox, Sophia E; Olsen, Ylva S.; Valiela, Ivan; Martinetto, Paulina; Iribarne, Oscar; Muto, Elizabeti Yuriko; PETTI, MONICA A.V.; Corbisier, Tha?s N; Soto-Jim?nez, Mart?n; P?ez-Osuna, Federico; Castro, Paula; Freitas, Helena; Zitelli, Andreina; Cardinaletti, Massimo

    2010-01-01

    Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- ...

  15. Benchmarking severe accident computer codes for heavy water reactor applications

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.H. [International Atomic Energy Agency, Vienna (Austria)

    2010-07-01

    Consideration of severe accidents at a nuclear power plant (NPP) is an essential component of the defence in depth approach used in nuclear safety. Severe accident analysis involves very complex physical phenomena that occur sequentially during various stages of accident progression. Computer codes are essential tools for understanding how the reactor and its containment might respond under severe accident conditions. International cooperative research programmes are established by the IAEA in areas that are of common interest to a number of Member States. These co-operative efforts are carried out through coordinated research projects (CRPs), typically 3 to 6 years in duration, and often involving experimental activities. Such CRPs allow a sharing of efforts on an international basis, foster team-building and benefit from the experience and expertise of researchers from all participating institutes. The IAEA is organizing a CRP on benchmarking severe accident computer codes for heavy water reactor (HWR) applications. The CRP scope includes defining the severe accident sequence and conducting benchmark analyses for HWRs, evaluating the capabilities of existing computer codes to predict important severe accident phenomena, and suggesting necessary code improvements and/or new experiments to reduce uncertainties. The CRP has been planned on the advice and with the support of the IAEA Nuclear Energy Department's Technical Working Groups on Advanced Technologies for HWRs. (author)

  16. Heavy metals in water, sediments and submerged macrophytes in ponds around the Dianchi Lake, China.

    Science.gov (United States)

    Wang, Zhixiu; Yao, Lu; Liu, Guihua; Liu, Wenzhi

    2014-09-01

    Through retaining runoff and pollutants such as heavy metals from surrounding landscapes, ponds around a lake play an important role in mitigating the impacts of human activities on lake ecosystems. In order to determine the potential for heavy metal accumulation of submerged macrophytes, we investigated the concentrations of 10 heavy metals (i.e., As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in water, sediments, and submerged macrophytes collected from 37 ponds around the Dianchi Lake in China. Our results showed that both water and sediments of these ponds were polluted by Pb. Water and sediments heavy metal concentrations in ponds received urban and agricultural runoff were not significantly higher than those in ponds received forest runoff. This result indicates that a large portion of heavy metals in these ponds may originate from atmospheric deposition and weathering of background soils. Positive relationships were found among heavy metal concentrations in submerged macrophytes, probably due to the coaccumulation of heavy metals. For most heavy metals, no significant relationships were found between submerged macrophytes and their water and sediment environments. The maximum concentrations of Cr, Fe and Ni in Ceratophyllum demersum were 4242, 16,429 and 2662mgkg(-1), respectively. The result suggests that C. demersum is a good candidate species for removing heavy metals from polluted aquatic environments. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Sediment-Water Exchange of Selected Heavy Metals at the ...

    African Journals Online (AJOL)

    Organic matter oxidation contributed to the mobilization of heavy metals, demonstrating the significant effect of atmospheric oxidation on heavy metals dynamics at the Makupa creek backwaters during low tide. Humic and fluvic acid mobilization did not have a significant effect in the mobilization of Fe (Pearson correlation ...

  18. Removal of heavy metals from waste water of tanning leather ...

    African Journals Online (AJOL)

    unguis. The isolated fungi were investigated for their potential to remove heavy metals from wastewater effluent of tanning leather industry. Such effluent was alkaline (pH, 8.2) with high content of total soluble salts (30.6 mS/cm) and heavy metals ...

  19. Electromyogram as a measure of heavy metal toxicity in fresh water and salt water mussels

    Energy Technology Data Exchange (ETDEWEB)

    Kidder, G.W. III [Illinois State Univ., Normal, IL (United States)]|[Mt. Desert Island Biological Lab., Salsbury Cove, ME (United States); McCoy, A.A. [Mt. Desert Island Biological Lab., Salsbury Cove, ME (United States)]|[Brown Univ., Providence, RI (United States)

    1996-02-01

    The response of bivalves to heavy metals and other toxins has usually been determined by observing valve position. Since mussels close their valves to avoid noxious stimuli, experimental delivery of chemicals ins uncertain. To obtain constant results plastic spacers can be employed to hold the valves apart. This obviates valve position as an index of response and some other method is required. Electromyography of intact mussels is one such index, giving a simple, effective, and quantitative measurement of activity. Experiments are reported in this article on the effects of added mercury on salt water and fresh water species.

  20. Influence of sediment organic enrichment and water alkalinity on growth of aquatic isoetid and elodeid plants

    DEFF Research Database (Denmark)

    Raun, Ane-Marie Løvendahl; Borum, Jens; Jensen, Kaj Sand

    2010-01-01

    ) and two elodeids (Potamogeton crispus and P. perfoliatus), we test whether organic enrichment of lake sediments has a long-lasting influence by: (i) reducing plant growth because of oxygen stress on plant roots and (ii) inhibiting growth more for isoetids than elodeids. We also test whether (iii...... because of greater CO2 supply from sediments being their main CO2 source. At higher organic enrichment, isoetid biomass was reduced, leaf chlorophyll declined up to 10-fold, root length declined from 7 to plant stress. 4. Lobelia was not affected by HCO...... development of all four species was so strongly restricted in sediments enriched with labile organic matter that plants if growing in situ may lose root anchorage. Other experiments demonstrate that this risk is enhanced by greater water content and reduced consolidation in organically rich sediments...

  1. Silica coated magnetite nanoparticles for removal of heavy metal ions from polluted waters

    CERN Document Server

    Dash, Monika

    2013-01-01

    Magnetic removal of Hg2+ and other heavy metal ions like Cd2+, Pb2+ etc. using silica coated magnetite particles from polluted waters is a current topic of active research to provide efficient water recycling and long term high quality water. The technique used to study the bonding characteristics of such kind of nanoparticles with the heavy metal ions is a very sensitive hyperfine specroscopy technique called the perturbed angular correlation technique (PAC).

  2. Trace elements affect methanogenic activity and diversity in enrichments from subsurface coal bed produced water

    Directory of Open Access Journals (Sweden)

    Burcu eÜnal

    2012-05-01

    Full Text Available Microbial methane from coal beds accounts for a significant and growing percentage of natural gas worldwide. Our knowledge of physical and geochemical factors regulating methanogenesis is still in its infancy. We hypothesized that in these closed systems, trace elements (as micronutrients are a limiting factor for methanogenic growth and activity. Trace elements are essential components of enzymes or cofactors of metabolic pathways associated with methanogenesis. This study examined the effects of eight trace elements (iron, nickel, cobalt, molybdenum, zinc, manganese, boron, and copper on methane production, on mcrA transcript levels, and on methanogenic community structure in enrichment cultures obtained from coal bed methane well produced water samples from the Powder River Basin, Wyoming. Methane production was shown to be limited both by a lack of additional trace elements as well as by the addition of an overly concentrated trace element mixture. Addition of trace elements at concentrations optimized for standard media enhanced methane production by 37%. After seven days of incubation, the levels of mcrA transcripts in enrichment cultures with trace element amendment were much higher than in cultures without amendment. Transcript levels of mcrA correlated positively with elevated rates of methane production in supplemented enrichments (R2=0.95. Metabolically-active methanogens, identified by clone sequences of mcrA mRNA retrieved from enrichment cultures, were closely related to Methanobacterium subterraneum and Methanobacterium formicicum. Enrichment cultures were dominated by M. subterraneum and had slightly higher predicted methanogenic richness, but less diversity than enrichment cultures without amendments. These results suggest that varying concentrations of trace elements in produced water from different subsurface coal wells may cause changing levels of coal bed methane production and alter the composition of the active

  3. Heavy metal pollution in drinking water - a global risk for human health

    African Journals Online (AJOL)

    Water resources in the world have been profoundly influenced over the last years by human activities, whereby the world is currently facing critical water supply and drinking water quality problems. In many parts of the world heavy metal (HM) concentrations in drinking water are higher than some international guideline ...

  4. Heavy metal ions adsorption from mine waters by sawdust

    Directory of Open Access Journals (Sweden)

    G. Bogdanović

    2009-10-01

    Full Text Available In this work the results on the batch and column adsorption of copper and some associated ions by employing linden and poplar sawdust as a low-cost adsorbent are presented. The mine water from a local abandoned copper mine, as well as synthetic solutions of those ions which are the main constituents of the mine water were both used as a model-system in this study. The adsorption ability of the chosen sawdust to adsorb heavy metal ions is considered as a function of the initial pH of the solution and kind of metal ions. At lower pH of solutions the adsorption percentage (AD % decreases leading to a zero AD % at pH < 1.1. Maximum AD % is achieved at 3.5 < pH < 5. It was found that poplar and linden sawdust have both almost equal adsorption capacities against copper ions. The highest AD % ( ≈80% was achieved for Cu2+, while for Fe2+ it was slightly above 10%. The other considered ions (Zn2+ and Mn2+ were within this interval. The results obtained in the batch mode were verified through the column test by using the real mine water originating from an acid mine drainage (AMD of the copper mine „Cerovo“, RTB Bor. The breakthrough curves are presented as a function of the aqueous phase volume passed through the column allowing having an insight into the column adsorption features. Breakthrough points were determined for copper, manganese and zinc ions. A very high adsorption degree – higher than 99% was achieved in these experiments for all mentioned ions. After completing the adsorption, instead of desorption, the loaded sawdust was drained, dried and burned; the copper bearing ash was then leached with a controlled volume of sulphuric acid solution to concentrate copper therein. The obtained leach solution had the concentration of copper higher than 15 g dm-3 and the amount of H2SO4 high enough to serve as a supporting electrolyte suitable to be treated by the electrowinning for recovery of copper. The technology process based on the column

  5. Estimating methane production rates in bogs and landfills by deuterium enrichment of pore water

    Science.gov (United States)

    Siegel, D.I.; Chanton, J.P.; Glaser, P.H.; Chasar, L.S.; Rosenberry, D.O.

    2001-01-01

    Raised bogs and municipal waste landfills harbor large populations of methanogens within their domed deposits of anoxic organic matter. Although the methane emissions from these sites have been estimated by various methods, limited data exist on the activity of the methanogens at depth. We therefore analyzed the stable isotopic signature of the pore waters in two raised bogs from northern Minnesota to identify depth intervals in the peat profile where methanogenic metabolism occurs. Methanogenesis enriched the deuterium (2H) content of the deep peat pore waters by as much as +11% (Vienna Standard Mean Sea Water), which compares to a much greater enrichment factor of +70% in leachate from New York City's Fresh Kills landfill. The bog pore waters were isotopically dated by tritium (3H) to be about 35 years old at 1.5 m depth, whereas the landfill leachate was estimated as ~ 17 years old from Darcy flow calculations. According to an isotopic mass balance the observed deuterium enrichment indicates that about 1.2 g of CH4m-3 d-1 were produced within the deeper peat, compared to about 2.8 g CH4 m-3 d-1 in the landfill. The values for methane production in the bog peat are substantially higher than the flux rates measured at the surface of the bogs or at the landfill, indicating that deeper methane production may be much higher than was previously assumed.

  6. Determination of the level of some heavy metals in water collected ...

    African Journals Online (AJOL)

    In view of this, levels of some heavy metals, Zn, Pb, Cr, Cu, Ni, Co, Ag, Fe and Mn were determined in water samples collected from two pollution prone areas around Kano (Sharada and Bompai industrial estates) and control site (Thomas Dam, Dambatta). The levels of the heavy metals were determined by Atomic ...

  7. Assessment of heavy metal pollution in drinking water due to mining ...

    African Journals Online (AJOL)

    Mining and smelting activities are the main causes for the increasing pollution of heavy metals from water sources. The toxicity of these heavy metals from the mining, milling and smelting companies can cause harmful and even lethal effects on the human health. The objective of this study was to investigate the level of As, ...

  8. Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: implications for dissemination of heavy metals.

    Science.gov (United States)

    Wu, Qihang; Leung, Jonathan Y S; Geng, Xinhua; Chen, Shejun; Huang, Xuexia; Li, Haiyan; Huang, Zhuying; Zhu, Libin; Chen, Jiahao; Lu, Yayin

    2015-02-15

    Illegal e-waste recycling activity has caused heavy metal pollution in many developing countries, including China. In recent years, the Chinese government has strengthened enforcement to impede such activity; however, the heavy metals remaining in the abandoned e-waste recycling site can still pose ecological risk. The present study aimed to investigate the concentrations of heavy metals in soil and water in the vicinity of an abandoned e-waste recycling site in Longtang, South China. Results showed that the surface soil of the former burning and acid-leaching sites was still heavily contaminated with Cd (>0.39 mg kg(-1)) and Cu (>1981 mg kg(-1)), which exceeded their respective guideline levels. The concentration of heavy metals generally decreased with depth in both burning site and paddy field, which is related to the elevated pH and reduced TOM along the depth gradient. The pond water was seriously acidified and contaminated with heavy metals, while the well water was slightly contaminated since heavy metals were mostly retained in the surface soil. The use of pond water for irrigation resulted in considerable heavy metal contamination in the paddy soil. Compared with previous studies, the reduced heavy metal concentrations in the surface soil imply that heavy metals were transported to the other areas, such as pond. Therefore, immediate remediation of the contaminated soil and water is necessary to prevent dissemination of heavy metals and potential ecological disaster. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Evaporative isotope enrichment as a constraint on reach water balance along a dryland river.

    Science.gov (United States)

    Gibson, John J; Sadek, Mostafa A; Stone, D J M; Hughes, Catherine E; Hankin, S; Cendon, Dioni I; Hollins, Suzanne E

    2008-03-01

    Deuterium and oxygen-18 enrichment in river water during its transit across dryland region is found to occur systematically along evaporation lines with slopes of close to 4 in (2)H-(18)O space, largely consistent with trends predicted by the Craig-Gordon model for an open-water dominated evaporating system. This, in combination with reach balance assessments and derived runoff ratios, strongly suggests that the enrichment signal and its variability in the Barwon-Darling river, Southeastern Australia is acquired during the process of evaporation from the river channel itself, as enhanced by the presence of abundant weirs, dams and other storages, rather than reflecting inherited enrichment signals from soil water evaporation in the watershed. Using a steady-state isotope mass balance analysis based on monthly (18)O and (2)H, we use the isotopic evolution of river water to re-construct a perspective of net exchange between the river and its contributing area along eight reaches of the river during a drought period from July 2002 to December 2003, including the duration of a minor flow event. The resulting scenario, which uses a combination of climatological averages and available real-time meteorological data, should be viewed as a preliminary test of the application rather than as a definitive inventory of reach water balance. As expected for a flood-driven dryland system, considerable temporal variability in exchange is predicted. While requiring additional real-time isotopic data for operational use, the method demonstrates potential as a non-invasive tool for detecting and quantifying water diversions, one that can be easily incorporated within existing water quality monitoring activities.

  10. [Pollution and Potential Ecology Risk Evaluation of Heavy Metals in River Water, Top Sediments on Bed and Soils Along Banks of Bortala River, Northwest China].

    Science.gov (United States)

    Zhang, Zhao-yong; Abuduwaili, Jilili; Jiang, Feng-qing

    2015-07-01

    This paper focuses on the sources, pollution status and potential ecology risks of heavy metals (Cr, Cu, Hg, As, Cd, Pb, and Zn) in the surface water, top sediment of river bed and soil along banks of Bortala River, which locates in the oasis region of Xinjiang, northwest China. Results showed that: (1) As a whole, contents of 7 tested heavy metals of Bortala River were low, while the maximum values of Hg, Cd, Pb, and Cr in the river water were significantly higher than those of Secondary Category of the Surface Water Quality Standards of People's Republic of China (GB 3838-2002) and Drinking Water Guideline from WHO. Analysis showed that the heavy metals contents of top sediment on river bed and soils along river banks were significantly higher than those of the river water. (Correlation analysis and enrichment factor (EF) calculation showed that in the river water, top sediment on river bed and soils along river banks, Hg, Cd, Pb, and Cr mainly originated from industrial emissions, urban and rural anthropogenic activities, transportation and agricultural production activities; While Cu, Zn, and As mainly originated from natural geological background and soil parent materials. (3) Pollution assessment showed that in three matrices, the single factor pollution index(Pi) and the integrated pollution index (Pz) of 7 heavy metals were all lower than 1, and they all belonged to safe and clean levels. (4) Potential ecology risk evaluation showed that as a whole the single factor potential ecological risk (Eir) and the integrated potential ecology risks (RI) of 7 heavy metals were relatively low, and would not cause threats to the health of water and soil environment of river basin, while the potential ecology risks of Cd, Hg, Pb, and Cr were significantly higher than those of other heavy metals.

  11. Characterization of heavy oils. 3: Prediction of gas injection behavior -- Swelling test, multicontact test, multiple-contact minimum miscibility pressure, and multiple-contact minimum miscibility enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Jaubert, J.N. [Ecole Nationale Superieure des Industries Chimiques, Nancy (France); Neau, E.; Avaullee, L. [Faculte des Sciences de Luminy, Marseille (France). Lab. de Chimie Physique; Zaborowski, G. [Compagnie Petroliere TOTAL, Saint-Remy-les-Chevreuse (France). Centre Scientifique et Technique

    1995-11-01

    The modeling of miscible gas injection into reservoir crude oils was performed using a cubic equation of state coupled with a predictive procedure for characterizing the heavy fractions. It is shown that experimental data on the swelling test, multicontact test, slim tube minimum miscibility pressure (MMP), and minimum miscibility enrichment (MME) for 10 different crude oils from different fields are satisfactorily calculated using the predictive characterization. However, in the case of MMP and MME calculations, a significant deviation may appear between predicted and experimental values. Reasons for this discrepancy are discussed. The influence of tuning the equation of state parameters in the estimation of results for the swelling test is also discussed.

  12. Occurrence and distribution of selected heavy metals in the surface sediments of South Brittany coastal waters: An assessment using pollution indicators

    Science.gov (United States)

    Ong, M. C.; Menier, D.; Noor Azhar, M. S.; Dupont, V.; Révillon, S.

    2012-04-01

    In order to avoid the pollution of heavy metals in South Brittany water, it is necessary to establish the data and understand the mechanisms influencing the distribution of heavy metals of the area. One of the aims of this work was to assess heavy metals contamination in Gulf of Morbihan and Quiberon Bay. Another aim was to use interpolation surfaces per metals to assess the contamination separately per metal. A total of 196 bottom sediment samples were collected from the coastal waters in order to determine the spatial concentration of Cr, Mn, Co, Cu, Zn, Cd and Pb by Inductively Coupled Plasma Mass Spectrometry (ICPMS) after acid digestion. The average heavy metal concentrations are ranked as follows: Mn>Zn>Cr>Pb>Cu>Cu>Cd. In the gulf, metal enrichments observed compared to the bay environment may due river run-off from three major river (Auray, Le Marle and Novalo rivers) which carried municipal waste and maritime activities along the coastal area within the gulf. Beside those factors, the natural factors such as the sheltered basin morphology itself, fine sediment and low hydrodynamic regime which favour the in situ accumulation of pollutants. The level of pollution levels attributed to heavy metals was evaluated using several pollution indicators in order to determine anthropogenically derived sediment contamination. Comparison to sediment quality guidelines (SQGs), enrichment factors (EFs), index of geoaccumulation (Igeo) and contamination factors (CF) based on reference element and background value to compensate for the influence of the natural variability in sediment mineralogy and to assess whether the concentration observed in surface sediment represent background and contaminated levels and visualize using ArcGIS software. These analyses validated that the bottom sediment only enriched in Pb and the other metals in most sample are not due to artificial contamination. Overall, geochemistry of the samples show the effect of both natural and anthropogenic

  13. Surveillance of parasitic Legionella in surface waters by using immunomagnetic separation and amoebae enrichment.

    Science.gov (United States)

    Hsu, Tsui-Kang; Wu, Shu-Fen; Hsu, Bing-Mu; Kao, Po-Min; Tao, Chi-Wei; Shen, Shu-Min; Ji, Wen-Tsai; Huang, Wen-Chien; Fan, Cheng-Wei

    2015-01-01

    Free-living amoebae (FLA) are potential reservoirs of Legionella in aquatic environments. However, the parasitic relationship between various Legionella and amoebae remains unclear. In this study, surface water samples were gathered from two rivers for evaluating parasitic Legionella. Warmer water temperature is critical to the existence of Legionella. This result suggests that amoebae may be helpful in maintaining Legionella in natural environments because warmer temperatures could enhance parasitisation of Legionella in amoebae. We next used immunomagnetic separation (IMS) to identify extracellular Legionella and remove most free Legionella before detecting the parasitic ones in selectively enriched amoebae. Legionella pneumophila was detected in all the approaches, confirming that the pathogen is a facultative amoebae parasite. By contrast, two obligate amoebae parasites, Legionella-like amoebal pathogens (LLAPs) 8 and 9, were detected only in enriched amoebae. However, several uncultured Legionella were detected only in the extracellular samples. Because the presence of potential hosts, namely Vermamoeba vermiformis, Acanthamoeba spp. and Naegleria gruberi, was confirmed in the samples that contained intracellular Legionella, uncultured Legionella may survive independently of amoebae. Immunomagnetic separation and amoebae enrichment may have referential value for detecting parasitic Legionella in surface waters.

  14. Leaf water 18 O and 2 H maps show directional enrichment discrepancy in Colocasia esculenta.

    Science.gov (United States)

    Gerlein-Safdi, Cynthia; Gauthier, Paul P G; Sinkler, Craig James; Caylor, Kelly Krispin

    2017-10-01

    Spatial patterns of leaf water isotopes are challenging to predict because of the intricate link between vein and lamina water. Many models have attempted to predict these patterns, but to date, most have focused on monocots with parallel veins. These provide a simple system to study, but do not represent the majority of plant species. Here, a new protocol is developed using a Picarro induction module coupled to a cavity ringdown spectrometer to obtain maps of the leaf water isotopes (18 O and 2 H). The technique is applied to Colocasia esculenta leaves. The results are compared with isotope ratio mass spectrometry. In C. esculenta, a large enrichment in the radial direction is observed, but not in the longitudinal direction. The string-of-lakes model fails to predict the observed patterns, while the Farquhar-Gan model is more successful, especially when enrichment is accounted for along the radial direction. Our results show that reticulate-veined leaves experience a larger enrichment along the axis of the secondary veins than along the midrib. We hypothesize that this is due to the lower major/minor vein ratio that leads to longer pathways between major veins and sites of evaporation. © 2017 John Wiley & Sons Ltd.

  15. A Review of Laboratory-Scale Research on Upgrading Heavy Oil in Supercritical Water

    Directory of Open Access Journals (Sweden)

    Ning Li

    2015-08-01

    Full Text Available With the growing demand for energy and the depletion of conventional crude oil, heavy oil in huge reserve has attracted extensive attention. However, heavy oil cannot be directly refined by existing processes unless they are upgraded due to its complex composition and high concentration of heteroatoms (N, S, Ni, V, etc.. Of the variety of techniques for heavy oil upgrading, supercritical water (SCW is gaining popularity because of its excellent ability to convert heavy oil into valued, clean light oil by the suppression of coke formation and the removal of heteroatoms. Based on the current status of this research around the world, heavy oil upgrading in SCW is summarized from three aspects: Transformation of hydrocarbons, suppression of coke, and removal of heteroatoms. In this work, the challenge and future development of the orientation of upgrading heavy oil in SCW are pointed out.

  16. Carbonate ion-enriched hot spring water promotes skin wound healing in nude rats.

    Directory of Open Access Journals (Sweden)

    Jingyan Liang

    Full Text Available Hot spring or hot spa bathing (Onsen is a traditional therapy for the treatment of certain ailments. There is a common belief that hot spring bathing has therapeutic effects for wound healing, yet the underlying molecular mechanisms remain unclear. To examine this hypothesis, we investigated the effects of Nagano hot spring water (rich in carbonate ion, 42°C on the healing process of the skin using a nude rat skin wound model. We found that hot spring bathing led to an enhanced healing speed compared to both the unbathed and hot-water (42°C control groups. Histologically, the hot spring water group showed increased vessel density and reduced inflammatory cells in the granulation tissue of the wound area. Real-time RT-PCR analysis along with zymography revealed that the wound area of the hot spring water group exhibited a higher expression of matrix metalloproteinases-2 and -9 compared to the two other control groups. Furthermore, we found that the enhanced wound healing process induced by the carbonate ion-enriched hot spring water was mediated by thermal insulation and moisture maintenance. Our results provide the evidence that carbonate ion-enriched hot spring water is beneficial for the treatment of skin wounds.

  17. "Periodic-table-style" paper device for monitoring heavy metals in water.

    Science.gov (United States)

    Li, Miaosi; Cao, Rong; Nilghaz, Azadeh; Guan, Liyun; Zhang, Xiwang; Shen, Wei

    2015-03-03

    If a paper-based analytical device (μ-PAD) could be made by printing indicators for detection of heavy metals in chemical symbols of the metals in a style of the periodic table of elements, it could be possible for such μ-PAD to report the presence and the safety level of heavy metal ions in water simultaneously and by text message. This device would be able to provide easy solutions to field-based monitoring of heavy metals in industrial wastewater discharges and in irrigating and drinking water. Text-reporting could promptly inform even nonprofessional users of the water quality. This work presents a proof of concept study of this idea. Cu(II), Ni(II), and Cr(VI) were chosen to demonstrate the feasibility, specificity, and reliability of paper-based text-reporting devices for monitoring heavy metals in water.

  18. Influence of Heavy Metal Stress On Water Regime of A Model Forest Ecosystem

    Science.gov (United States)

    Menon, M.; Abbaspour, K. C.; Schulin, R.

    Among various toxic substances that contaminate the soil, the effects of heavy metals are particularly severe on all aspects of soil-plant system. The Swiss Federal Institute for Forest Snow and Land Research (WSL) is addressing comprehensively the issue of heavy metal toxicity in a forest ecosystem in a project titled Sfrom cell to treeT. As & cedil; part of the above project an investigation is being carried out to evaluate the impact of heavy metal stress on water regime of a young forest ecosystem grown in sixteen open top lysimeters. The factorial treatments of the lysimeters include variations of rainwa- ter acidity (acidic, neutral), subsoil type (acidic, calcareous), and heavy metal con- centration (with and without heavy metals in the top 20 cm). Filling of lysimeters was completed in November 1999. Each model ecosystem was planted in spring 2000 with the same collection of trees and herbaceous plants. Each lysimeters is equipped with tensiometers for monitoring of pressure head, time domain reflectometry for moni- toring of water content, and sprinkler devices for application of controlled irrigation. Drainage water data are measured regularly from the canisters installed at the bot- tom of lysimeters and evapotranspiration is calculated through water balancing. Our preliminary analyses of the data shoed the following results. Weekly data collected from May to October 2001 indicated higher amount of percolating water in acidic soil compared to the neutral soil due to textural difference. At 12 cm depth in both soils, control and acidic rain showed lower water potential than heavy metal and combina- tion of acidic rain with heavy metal treatments. In lower depths, water potential did not show much difference between treatments. Water contents showed differences be- tween treatments in the upper part of the profile where the soil is contaminated with heavy metals. Higher water content was observed in heavy metal treatment at 0-25 cm depth than 25-50 cm

  19. A study on the establishment of component/equipment performance criteria considering Heavy Water Reactor characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Keun Sun; Kwon, Young Chul; Lee, Min Kyu; Lee, Yun Soo [Sunmoon Univ., Asan (Korea, Republic of); Chang, Seong Hoong; Ryo, Chang Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Kim, Soong Pyung; Hwnag, Jung Rye; Chung, Chul Kee [Chosun Univ., Gwangju (Korea, Republic of)

    2002-03-15

    Foreign and domestic technology trends, regulatory requirements, design and researches for heavy water reactors are analyzed. Safety design guides of Canada industry and regulatory documents and consultative documents of Canada regulatory agency are reviewed. Applicability of MOST guidance 16 Revision 'guidance for technical criteria of nuclear reactor facility' is reviewed. Specific performance criteria are established for components and facilities for heavy water reactor.

  20. Computational study of fingering phenomenon in heavy oil reservoir with water drive

    OpenAIRE

    Wijeratne, D. I. Erandi N.; Halvorsen, Britt

    2015-01-01

    The objective of this paper is to numerically study the flow in heavy oil reservoir with water drive. The main focus is to investigate the viscous fingering phenomenon and how it affects the oil recovery. Two-dimensional simulations of oil production in a homogeneous heavy oil reservoir were carried out using ANSYS Fluent as the Computational Fluid Dynamics software. Cross section of the reservoir is simulated to study the fingering behaviour; an instability which occurs in the water oil cont...

  1. Enrichment of 88Sr in continental waters due to calcium carbonate precipitation

    Science.gov (United States)

    Shalev, Netta; Gavrieli, Ittai; Halicz, Ludwik; Sandler, Amir; Stein, Mordechai; Lazar, Boaz

    2017-02-01

    δ88/86Sr data published over the last few years suggest that continental waters are enriched with 88Sr as compared to the rocks in their drainage basins. In an attempt to understand this phenomenon, this study established the fractionation in the 88Sr/86Sr ratio during precipitation of continental carbonates (i.e., carbonates precipitated on land from surface, pedogenic, or ground waters), and evaluated the contribution of this process to the 88Sr-enrichment in rivers. For this, stable and radiogenic Sr isotopes (88Sr, 87Sr and 86Sr) were measured in calcite samples and their precipitating waters collected in various continental environments, such as soil, cave, streams and groundwater. The results indicate that continental carbonates are 88Sr-depleted relative to their precipitating waters, placing them as one of the most 88Sr-depleted reservoirs on earth. The average difference in δ88/86Sr values between waters and solid CaCO3 (tufas or speleothems) that they precipitate is Δcarb-water = - 0.218 ± 0.014 ‰ (1SD). An even larger fractionation (εcarb-water = - 0.285 ± 0.02 ‰) was measured in groundwater with particularly high carbonate-alkalinity and high carbonate precipitation rate that depleted ∼65% of the Sr in the groundwater, resulting in substantial 88Sr-enrichment in the residual dissolved Sr (δ88/86Sr = 0.656 ‰). Results also suggest that pedogenic carbonate precipitation in soil profile removes 50-85% of the Sr from the recharging soil-water, thereby increasing the δ88/86Sr value of the soil-water from ∼ 0.18 ‰ to 0.3 ‰- 0.6 ‰. Similar 88Sr-enrichment was observed in drip water from a karst cave. A maximum removal flux of Sr into continental carbonates of about 20 Gmol(Sr)ṡy-1 is required to yield the reported 88Sr-enrichment in global rivers (δ88/86Sr = 0.32 ‰) relative to their rock sources when using the fractionation factor derived in this study, Δcarb-water = - 0.218 ‰, and the published δ88/86Sr composition of marine

  2. Evaluations of the Levels of Heavy Metals in River Water and ...

    African Journals Online (AJOL)

    ADOWIE PERE

    plastic bottles with screw caps and frozen at -5 oC. The water samples were acidified with 5 ml of concentrated nitric acid prior to preservation to ensure that heavy ... fishermen and then placed into an ice box and transported to the laboratory within 24 hours. Preparation of water and fish samples: Water samples were ...

  3. Comparative study of electrical breakdown properties of deionized water and heavy water under pulsed power conditions

    Science.gov (United States)

    Veda Prakash, G.; Kumar, R.; Saurabh, K.; Nasir, Anitha, V. P.; Chowdhuri, M. B.; Shyam, A.

    2016-01-01

    A comparative study of electrical breakdown properties of deionized water (H2O) and heavy water (D2O) is presented with two different electrode materials (stainless steel (SS) and brass) and polarity (positive and negative) combinations. The pulsed (˜a few tens of nanoseconds) discharges are conducted by applying high voltage (˜a few hundred kV) pulse between two hemisphere electrodes of the same material, spaced 3 mm apart, at room temperature (˜26-28 °C) with the help of Tesla based pulse generator. It is observed that breakdown occurred in heavy water at lesser voltage and in short duration compared to deionized water irrespective of the electrode material and applied voltage polarity chosen. SS electrodes are seen to perform better in terms of the voltage withstanding capacity of the liquid dielectric as compared to brass electrodes. Further, discharges with negative polarity are found to give slightly enhanced discharge breakdown voltage when compared with those with positive polarity. The observations corroborate well with conductivity measurements carried out on original and post-treated liquid samples. An interpretation of the observations is attempted using Fourier transform infrared measurements on original and post-treated liquids as well as in situ emission spectra studies. A yet another important observation from the emission spectra has been that even short (nanosecond) duration discharges result in the formation of a considerable amount of ions injected into the liquid from the electrodes in a similar manner as reported for long (microseconds) discharges. The experimental observations show that deionised water is better suited for high voltage applications and also offer a comparison of the discharge behaviour with different electrodes and polarities.

  4. Comparative study of electrical breakdown properties of deionized water and heavy water under pulsed power conditions.

    Science.gov (United States)

    Veda Prakash, G; Kumar, R; Saurabh, K; Nasir; Anitha, V P; Chowdhuri, M B; Shyam, A

    2016-01-01

    A comparative study of electrical breakdown properties of deionized water (H2O) and heavy water (D2O) is presented with two different electrode materials (stainless steel (SS) and brass) and polarity (positive and negative) combinations. The pulsed (∼a few tens of nanoseconds) discharges are conducted by applying high voltage (∼a few hundred kV) pulse between two hemisphere electrodes of the same material, spaced 3 mm apart, at room temperature (∼26-28 °C) with the help of Tesla based pulse generator. It is observed that breakdown occurred in heavy water at lesser voltage and in short duration compared to deionized water irrespective of the electrode material and applied voltage polarity chosen. SS electrodes are seen to perform better in terms of the voltage withstanding capacity of the liquid dielectric as compared to brass electrodes. Further, discharges with negative polarity are found to give slightly enhanced discharge breakdown voltage when compared with those with positive polarity. The observations corroborate well with conductivity measurements carried out on original and post-treated liquid samples. An interpretation of the observations is attempted using Fourier transform infrared measurements on original and post-treated liquids as well as in situ emission spectra studies. A yet another important observation from the emission spectra has been that even short (nanosecond) duration discharges result in the formation of a considerable amount of ions injected into the liquid from the electrodes in a similar manner as reported for long (microseconds) discharges. The experimental observations show that deionised water is better suited for high voltage applications and also offer a comparison of the discharge behaviour with different electrodes and polarities.

  5. Construction management of Indian pressurized heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bohra, S.A. [Nuclear Power Corporation of India Limited, Vikram Sarabhai Bhavan, Anushaktinagar, Mumbai 400094 (India)]. E-mail: sabohra@npcil.co.in; Sharma, P.D. [Nuclear Power Corporation of India Limited, Vikram Sarabhai Bhavan, Anushaktinagar, Mumbai 400094 (India)

    2006-04-15

    Pandit Jawaharlal Nehru and Dr. Homi J. Bhabha, the visionary architects of Science and Technology of modern India foresaw the imperative need to establish a firm base for indigenous research and development in the field of nuclear electricity generation. The initial phase has primarily focused on the technology development in a systematic and structured manner, which has resulted in establishment of strong engineering, manufacturing and construction base. The nuclear power program started with the setting up of two units of boiling light water type reactors in 1969 for speedy establishment of nuclear technology, safety culture, and development of operation and maintenance manpower. The main aim at that stage was to demonstrate (to ourselves, and indeed to the rest of the world) that India, inspite of being a developing country, with limited industrial infrastructure and low capacity power grids, could successfully assimilate the high technology involved in the safe and economical operation of nuclear power reactors. The selection of a BWR was in contrast to the pressurized heavy water reactors (PHWR), which was identified as the flagship for the first stage of India's nuclear power program. The long-term program in three stages utilizes large reserves of thorium in the monazite sands of Kerala beaches in the third stage with first stage comprising of series of PHWR type plants with a base of 10,000 MW. India has at present 14 reactors in operation 12 of these being of PHWR type. The performance of operating units of 2720 MW has improved significantly with an overall capacity factor of about 90% in recent times. The construction work on eight reactor units with installed capacity of 3960 MW (two PHWRs of 540 MW each, four PHWRs of 220 MW each and two VVERs of 1000 MW each) is proceeding on a rapid pace with project schedules of less than 5 years from first pour of concrete. This is being achieved through advanced construction technology and management. Present

  6. Assessment of heavy metals concentration in water, soil sediment ...

    African Journals Online (AJOL)

    The term heavy metal refers to any metallic chemical element that has a relatively high density and is toxic at low concentrations. This study was conducted in four eastern Rift Valley lakes which included Lakes Oloidien, Crater, Elementaita and Nakuru, to determine the presence and levels of lead, arsenic, cadmium and ...

  7. INTRODUCTION Heavy metal pollution of water has become a ...

    African Journals Online (AJOL)

    major environmental problem almost since the advent of agricultural ... Nations state that monitoring eight elements in fish Hg, Cd, Pb, As, Cu, ..... Research J. Environ. Science, 3 (5):522-529. Staniskiene, B.; Matusevicius, P.; Budreckiene, R. and Skibniewska, K.A. 2006. Distribution of heavy metals in tissues of freshwater.

  8. Bioaccumulation of heavy metals in water, sediment and fish ...

    African Journals Online (AJOL)

    The highest levels of heavy metal accumulated in the liver of C. anguillaris were Fe, Cu, Pb, Cd and Zn than accumulated in O. niloticus. In gills of C. anguillaris, the highest accumulation of metal levels were Zn, Fe, Pb, Cd and Cu than accumulation in gills of O. niloticus. In muscles of C. anguillaris, the highest accumulation ...

  9. Concentration of Heavy Metals in Drinking Water from Urban Areas ...

    African Journals Online (AJOL)

    Bheema

    such as temperature, conductivity, total dissolved solids (TDS), salinity, pH, and turbidity and ten heavy metals ... highlighted recently in Bangladesh where natural levels of arsenic in groundwater were found to be causing ... could be soil erosion, domestic waste from urban and rural areas and industrial wastes. So far, no ...

  10. Concentration of Heavy Metals in Drinking Water from Urban Areas ...

    African Journals Online (AJOL)

    Bheema

    highlighted recently in Bangladesh where natural levels of arsenic in groundwater were found to be causing harmful ... are higher than the recommended limits, their roles change to a negative dimension. Human. © CNCS .... Analytical grade chemicals (HNO3, Sigma chemicals, Australia and standard heavy metal solutions ...

  11. Removal of heavy metals from waste water of tanning leather ...

    African Journals Online (AJOL)

    LG

    2013-07-03

    Jul 3, 2013 ... are expensive, need energy and can produce waste products that require careful disposal (Ahalya et al.,. 2003). Therefore, the biological approaches have been considered as an alternative remediation for heavy metals removal from wastewaters (Pena-Castro et al.,. 2004). One of these methods is the ...

  12. USING BIOPOLYMERS TO REMOVE HEAVY METALS FROM SOIL AND WATER

    Science.gov (United States)

    Chemical remediation of soil may involve the use of harsh chemicals that generate waste streams, which may adversely affect the soil's integrity and ability to support vegetation. This article reviews the potential use of benign reagents, such as biopolymers, to extract heavy me...

  13. Concentration of Heavy Metals in Drinking Water from Urban Areas ...

    African Journals Online (AJOL)

    Bheema

    More than 93.4% of the samples were within the United States Environmental Protection. Agency (US ... (64.18 %), iron (37.31 %), nickel (7 %), and lead (29.85 %) crossed the maximum admissible and desirable ... Heavy metals normally occurring in nature are not harmful to our environment because they are only present ...

  14. DETERMINATION OF HEAVY METALS IN FISH, WATER AND SEDIMENTS OF AVSAR DAM LAKE IN TURKEY

    Directory of Open Access Journals (Sweden)

    M. Öztürk ، G. Özözen ، O. Minareci ، E. Minareci

    2009-04-01

    Full Text Available In the present study, some heavy metals (Cd, Cr, Cu, Fe, Ni and Pb were seasonally determined in water, sediment and some tissues of Cyprinus carpio from Avsar Dam Lake, which is an important water source for irrigation and drinking in Turkey. Heavy metal levels in water, sediment and fish samples were analyzed by inductively coupled plasma spectroscopy (ICP/AES. The obtained results showed that the average values of Fe in water samples were higher than the respective reference values for fresh water. Results for levels in water were compared with national and international water quality guidelines, as well as literature data reported for the lakes. The analysis of heavy metals in sediments indicated that among the six heavy metals tested, Fe was maximally accumulated, followed by Ni, Cu, Cr, Pb and Cd. Heavy metal concentrations were found to decrease in sequence of the Cyprinus carpio samples, in the muscle and stomach-intestine as Fe > Cu > Pb> Ni > Cr > Cd; in the gill, heart and liver as Fe > Cu > Ni > Pb > Cr > Cd and in the air sac as Fe > Cu > Ni > Pb > Cd >Cr. In the fish samples, cadmium, chromium, nickel and lead concentrations exceeded the tolerable values provided by international institutions.

  15. Heavy metal distribution and water quality characterization of water bodies in Louisiana's Lake Pontchartrain Basin, USA.

    Science.gov (United States)

    Zhang, Zengqiang; Wang, Jim J; Ali, Amjad; DeLaune, Ronald D

    2016-11-01

    The seasonal variation in physico-chemical properties, anions, and the heavy metal (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) concentration was evaluated in water from nine different rivers in Lake Pontchartrain Basin, Louisiana, USA. The water quality parameters were compared with toxicity reference values (TRV), US Environmental Protection Agency (USEPA) drinking/aquatic life protection, and WHO standards. Among physico-chemical properties, pH, DO, and turbidity were high during spring, while, EC, temperature, and DOC were high during summer and vice versa. The anion study revealed that the concentrations of F(-), Cl(-), and NO3(-) were higher during summer and Br(-) and SO4(-) were higher during spring. Our research findings showed anion concentration decreased in the order of Cl(-) > SO4(-) > NO3(-) > Br(-) > F(-), in accordance with the global mean anion concentration. The dissolved heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb) except Zn were higher during spring than summer. None of the rivers showed any Cd pollution for both seasons. Co showed higher concentrations in Amite River, Mississippi River, Industrial Canal, and Lacombe Bayou during summer. The Cr concentration was higher than WHO drinking water standards, implicating water unsuitability for drinking purposes in all the rivers associated with the Lake Pontchartrain Basin. Cu showed no pollution risk for the study area. Mn and Co were similar to concentration in Lacombe Bayou, Liberty Bayou, Blind River, and Industrial Canal. Mn levels were greater than WHO standards for the Tickfaw River, Tangipahoa River, and Blind River in both seasons. Blind River, Tangipahoa River, Tickfaw River, and Amite River will require more monitoring for determining possible Mn pollution. Ni content in river water during both seasons showed low pollution risk. Liberty Bayou and Industrial Canal concentrations were closer to the WHO regulatory standards, indicating possible risk of Pb pollution in these water bodies. The Zn

  16. Using biopolymers to remove heavy metals from soil and water

    Energy Technology Data Exchange (ETDEWEB)

    Krishnamurthy, S.; Frederick, R.M.

    1993-11-19

    Chemical remediation of soil may involve the use of harsh chemicals that generate waste streams, which may adversely affect the soil's integrity and ability to support vegetation. This article reviews the potential use of benign reagents, such as biopolymers, to extract heavy metals. The biopolymers discussed are chitin and chitosan, modified starch, cellulose, and polymer-containing algae. (Copyright (c) Remediation 1994.)

  17. Analysis of heavy soils water retention curves with respect to volume changes

    Science.gov (United States)

    Kandra, B.; Tall, A.; Gomboš, M.; Pavelková, D.

    2017-10-01

    This work analyses the problem of measuring water retention curves in heavy soils. The results present the differences between soil water retention curves measured in soil samples collected from the selected localities of the Czech and Slovak area. In the drying process, the results showed an increased rate of soil shrinkage depending on clay content and water content. The rate of shrinkage affected the results of the water retention curves points measurement.

  18. Antioxidant activity of water extracts from fruit body of Lentinus edodes enriched with selenium

    Directory of Open Access Journals (Sweden)

    Savić Milena D.

    2011-01-01

    Full Text Available Shiitake (Lentinus edodes belongs to medically important and delicious fungi. It is recognizable for its healing properties, excellent taste and rich aroma. According to the traditional Japanese and Chinese medicine, shiitake mushroom significantly increases the strength and vitality of the body. Shiitake contains immunostimulants, compounds that lower cholesterol, prevents clogging of blood vessels, regulates the pressure, balances blood sugar levels, regulates digestion, and improves the performance of respiratory organs by its antirheumatic and antiallergic activities. Shiitake is recommended to use as food, prevention and cure, usually in a form of a spice (dried and ground or tea. It can be consumed fresh, too. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water extracts from fruit body of Lentinus edodes. The fungus was enhanced by adding organic selenium, zinc (II complex with the ligand 2.6-bis diacetylpyridine (selenosemicarbazon and inorganic compounds (Na2SeO3 of selenium in nutritional substrate where the fungus was grown. The total selenium content in fruit body was around 50 ppm for the sample enriched with selenium originating from organic sources, and 80 ppm for the sample enriched with selenium from inorganic sources. Samples were prepared by extraction of fruiting bodies in heated water. The results indicated that water extracts of whole fruit bodies, from both control and mushrooms supplemented with selenium, had quite good antioxidant activity. However, there was no significant difference between the samples supplemented with selenium content and those that were not.

  19. The enrichment and removal of arsenic (III) from water samples using HFSLM

    Science.gov (United States)

    Mafu, L. D.; Msagati, T. A. M.; Mamba, B. B.

    At specific concentrations oxyanions such as arsenic pose a major threat to human beings and to the environment because of their ability to biomagnify. The World Health Organization has set the drinking water standard at 10 μg l-1 for arsenic. It is in this regard that novel and cheaper methods to detect oxyanions and remove them from the environment are developed. In this work, we have developed sample preparation methods involving solid phase and liquid membrane for the extraction and enrichment of these oxyanions in aqueous environments. Various parameters which govern their optimal extraction and enrichment have been optimised. The manipulation of the liquid membrane extraction process was utilised to selectively extract arsenic (III) which is more toxic as compared to arsenic (V). The liquid membrane consisted of a combination of two organic solvents, and n-undecane and di-n-hexyl ether were used in a combination at various ratios of the two liquid membranes. The means of detection was by graphite furnace atomic absorption spectroscopy (GFAAS) as well as inductively coupled plasma optical emission spectroscopy (ICP-OES). The applicability of the method was tested in real wastewater samples where it was able to remove at least 50% of As (III) with enrichment factors of up to 20.

  20. Alginate immobilized enrichment culture for atrazine degradation in soil and water system.

    Science.gov (United States)

    Kumar, Anup; Nain, Lata; Singh, Neera

    2017-04-03

    An atrazine degrading enrichment culture, a consortium of bacteria of genus Bacillus along with Pseudomonas and Burkholderia, was immobilized in sodium alginate and was used to study atrazine degradation in mineral salts medium (MSM), soil and wastewater effluent. Sodium alginate immobilized consortium, when stored at room temperature (24 ± 5°C), was effective in degrading atrazine in MSM up to 90 days of storage. The survival of bacteria in alginate beads, based on colony formation unit (CFU) counts, suggested survival up to 90 days and population counts decreased to 1/5 th on 120 days. Comparison of atrazine degrading ability of the freely suspended enrichment culture and immobilized culture suggested that the immobilized culture took longer time for complete degradation of atrazine as a lag phase of 2 days was observed in the MSM inoculated with alginate immobilized culture. The free cells resulted in complete degradation of atrazine within 6 days, while immobilized cells took 10 days for 100% atrazine degradation. Further, immobilized cultures were able to degrade atrazine in soil and wastewater effluent. Alginate beads were stable and effective in degrading atrazine till 3rd transfer and disintegrated thereafter. The study suggested that immobilized enrichment culture, due to its better storage and application, can be used to degrade atrazine in soil water system.

  1. Licensing assessment of the Candu Pressurized Heavy Water Reactor. Preliminary safety information document. Volume II. [USA

    Energy Technology Data Exchange (ETDEWEB)

    1977-06-01

    ERDA has requested United Engineers and Constructors (UE and C) to evaluate the design of the Canadian natural uranium fueled, heavy water moderated (CANDU) nuclear reactor power plant to assess its conformance with the licensing criteria and guidelines of the U.S. Nuclear Regulatory Commission (USNRC) for light water reactors. This assessment was used to identify cost significant items of nonconformance and to provide a basis for developing a detailed cost estimate for a 1140 MWe, 3-loop Pressurized Heavy Water Reactor (PHWR) located at the Middletown, USA Site.

  2. Toenail as a biomarker of heavy metal exposure via drinking water: a systematic review.

    Science.gov (United States)

    Ab Razak, Nurul Hafiza; Praveena, Sarva Mangala; Hashim, Zailina

    2015-01-01

    Toenail is metabolic end product of the skin, which can provide information about heavy metal accumulation in human cells. Slow growth rates of toenail can represent heavy metal exposure from 2 to 12 months before the clipping. The toenail is a non-invasive biomarker that is easy to collect and store and is stable over time. In this systematic review, the suitability of toenail as a long-term biomarker was reviewed, along with the analysis and validation of toenail and confounders to heavy metal. This systematic review has included 30 articles chosen from a total of 132 articles searched from online electronic databases like Pubmed, Proquest, Science Direct, and SCOPUS. Keywords used in the search included "toenail", "biomarker", "heavy metal", and "drinking water". Heavy metal in toenail can be accurately analyzed using an ICP-MS instrument. The validation of toenail heavy metal concentration data is very crucial; however, the Certified Reference Material (CRM) for toenail is still unavailable. Usually, CRM for hair is used in toenail studies. Confounders that have major effects on heavy metal accumulation in toenail are dietary intake of food and supplement, smoking habit, and overall health condition. This review has identified the advantages and limitations of using toenail as a biomarker for long-term exposure, which can help future researchers design a study on heavy metal exposure using toenail.

  3. assessment of heavy metals in surface water of the ikpoba reservoir ...

    African Journals Online (AJOL)

    2013-03-01

    Mar 1, 2013 ... screw caps at approximately 30cm below the water surface. The bottles were treated with 5% nitric acid and rinsed with distilled water before use. ... an ice chest within 24 hours and were stored at -5‰ in a Haier Thermocool freezer prior to further analy- sis. Heavy metal analysis was carried out with a Buck.

  4. Heavy metal content in fish and water from River Niger at ...

    African Journals Online (AJOL)

    The concentrations of Lead (Pb), Copper (Cu), Cadmium (Cd) and Zinc (Zn) in fish and water from River Niger at Agenebode, Nigeria were determined by atomic absorption spectrometric technique. The mean concentrations of heavy metals in water ranged from 0.00742 mg/L for Pb to 0.239 mg/L for Zn. The summary ...

  5. Toxic Levels of Some Heavy Metals in Drinking Network Surface Water of Damietta Governorate, Egypt

    OpenAIRE

    EL-Bady, M. S. M.

    2016-01-01

    In this paper, the heavy metals of the surface drinking water of Damietta governorate were evaluated. Damietta district, Farascore City, EL-Zarka City and Kafr Saad City are the main locations of drinking water pollution. The villages of the Damietta governorate have concentration values less than the permissible limits of World Health Organization (WHO) and Egyptian Ministry Health (EMH).

  6. Reduction of bioavailability and leachability of heavy metals during vermicomposting of water hyacinth.

    Science.gov (United States)

    Singh, Jiwan; Kalamdhad, Ajay S

    2013-12-01

    Vermicomposting of water hyacinth is a good alternative for the treatment of water hyacinth (Eichhornia crassipes) and subsequentially, beneficial for agriculture purposes. The bioavailability and leachability of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) were evaluated during vermicomposting of E. crassipes employing Eisenia fetida earthworm. Five different proportions (trials 1, 2, 3, 4, and 5) of cattle manure, water hyacinth, and sawdust were prepared for the vermicomposting process. Results show that very poor biomass growth of earthworms was observed in the highest proportion of water hyacinth (trial 1). The water soluble, diethylenetriaminepentaacetic acid (DTPA) extractable, and leachable heavy metals concentration (percentage of total heavy metals) were reduced significantly in all trials except trial 1. The total concentration of some metals was low but its water soluble and DTPA extractable fractions were similar or more than other metals which were present in higher concentration. This study revealed that the toxicity of metals depends on bioavailable fraction rather than total metal concentration. Bioavailable fraction of metals may be toxic for plants and soil microorganisms. The vermicomposting of water hyacinth by E. fetida was very effective for reduction of bioavailability and leachability of selected heavy metals. Leachability test confirmed that prepared vermicompost is not hazardous for soil, plants, and human health. The feasibility of earthworms to mitigate the metal toxicity and to enhance the nutrient profile in water hyacinth vermicompost might be useful in sustainable land renovation practices at low-input basis.

  7. Heavy metal content in fish and water from River Niger at ...

    African Journals Online (AJOL)

    user

    The concentrations of Lead (Pb), Copper (Cu), Cadmium (Cd) and Zinc (Zn) in fish and water from River. Niger at Agenebode, Nigeria were determined by atomic absorption spectrometric technique. The mean concentrations of heavy metals in water ranged from 0.00742 mg/L for Pb to 0.239 mg/L for Zn. The summary ...

  8. Trace Analysis of Heavy Metals in Ground Waters of Vijayawada Industrial Area

    Science.gov (United States)

    Tadiboyina, Ravisankar; Ptsrk, Prasada Rao

    2016-01-01

    In recent years, the new environmental problem are arising due to industrial hazard wastage, global climate change, ground water contamination and etc., gives an attention to protect environment.one of the major source of contamination of ground water is improper discharge of industrial effluents these effluents contains so many heavy metals which…

  9. The study heavy metals in water,soil and Vegatable in Shahroud

    OpenAIRE

    saied Nazemi; ahmad khosravi

    2011-01-01

    Introduction: The arrival of toxic metals by human activities has lead to the contamination of soil. Heavy metals are among the most important pollutants in the environment. This study aimed at determining the concentration of heavy metals in soils, water and vegetables of Shhnama region in Shahroud. Methods: Vegetables studied included parsley, leek, leaf beet, fenugreek, cress, basil, radish and the coriander. The sampling was performed during 3 months, from September to October, 2008. The ...

  10. Assessment of irradiation effects on beryllium reflector and heavy water tank of JRR-3M

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Yoji; Kakehuda, Kazuhiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    The JRR-3M, a swimming pool type research reactor with beryllium and heavy water reflectors, has been operated since 1990. Since the beryllium reflectors are close to fuel and receive high fast neutron fluence in a relatively short time, they may be subject to change their dimensions by swelling due mostly to entrapped helium gaseous. This may bend the reflectors to the outside and narrow gaps between the reflectors and the fuel elements. The gaps have been measured with an ultrasonic thickness gage in an annual inspection. The results in 1996 show that the maximum of expansion in the diametral directions was 0.6 mm against 1.6 mm of a managed value for replacement of the reflector. A heavy water tank of the JRR-3M is made of aluminum alloy A5052. Surveillance tests of the alloy have been conducted to evaluate irradiation effects of the heavy water tank. Five sets of specimens of the alloy have been irradiated in the beryllium reflectors where fast neutron flux is higher than that in the heavy water tank. In 1994, one set of specimens had been unloaded and carried out the post-irradiation tests. The results show that the heavy water tank preserved satisfactory mechanical properties. (author)

  11. Criticality experiments with low enriched UO/sub 2/ fuel rods in water containing dissolved gadolinium

    Energy Technology Data Exchange (ETDEWEB)

    Bierman, S.R.; Murphy, E.S.; Clayton, E.D.; Keay, R.T.

    1984-02-01

    The results obtained in a criticality experiments program performed for British Nuclear Fuels, Ltd. (BNFL) under contract with the United States Department of Energy (USDOE) are presented in this report along with a complete description of the experiments. The experiments involved low enriched UO/sub 2/ and PuO/sub 2/-UO/sub 2/ fuel rods in water containing dissolved gadolinium, and are in direct support of BNFL plans to use soluble compounds of the neutron poison gadolinium as a primary criticality safeguard in the reprocessing of low enriched nuclear fuels. The experiments were designed primarily to provide data for validating a calculation method being developed for BNFL design and safety assessments, and to obtain data for the use of gadolinium as a neutron poison in nuclear chemical plant operations - particularly fuel dissolution. The experiments program covers a wide range of neutron moderation (near optimum to very under-moderated) and a wide range of gadolinium concentration (zero to about 2.5 g Gd/l). The measurements provide critical and subcritical k/sub eff/ data (1 greater than or equal to k/sub eff/ greater than or equal to 0.87) on fuel-water assemblies of UO/sub 2/ rods at two enrichments (2.35 wt % and 4.31 wt % /sup 235/U) and on mixed fuel-water assemblies of UO/sub 2/ and PuO/sub 2/-UO/sub 2/ rods containing 4.31 wt % /sup 235/U and 2 wt % PuO/sub 2/ in natural UO/sub 2/ respectively. Critical size of the lattices was determined with water containing no gadolinium and with water containing dissolved gadolinium nitrate. Pulsed neutron source measurements were performed to determine subcritical k/sub eff/ values as additional amounts of gadolinium were successively dissolved in the water of each critical assembly. Fission rate measurements in /sup 235/U using solid state track recorders were made in each of the three unpoisoned critical assemblies, and in the near-optimum moderated and the close-packed poisoned assemblies of this fuel.

  12. levels of heavy metals in gubi dam water bauchi, nigeria

    African Journals Online (AJOL)

    Ada

    constituents or pollutants in natural waters are the particles. All substances that ... rivers to the ocean is in the form of particulate matter (Martin and ..... pollution. Water Research, 9: pp. 189-. 195. Aston S.R. and Thornton, I., 1977. Regional geochemical data in relation to seasonal variations in water quality. Science of the.

  13. Physico-chemical properties and heavy metal content of water ...

    African Journals Online (AJOL)

    user

    The water quality examination in Ife–North Local Government of Osun State Nigeria was conducted by determining the physico–chemical parameters of 40 samples. Surface water, bore holes, wells and pipe borne water samples were collected from major towns in the Local Government Area and analyzed. Results showed ...

  14. Nutrient and Organic Carbon Losses, Enrichment Rate, and Cost of Water Erosion

    Directory of Open Access Journals (Sweden)

    Ildegardis Bertol

    Full Text Available ABSTRACT Soil erosion from water causes loss of nutrients and organic carbon, enriches the environment outside the erosion site, and results in costs. The no-tillage system generates increased nutrient and C content in the topsoil and, although it controls erosion, it can produce a more enriched runoff than in the conventional tillage system. This study was conducted in a Humic Cambisol in natural rainfall from 1997 to 2012 to quantify the contents and total losses of nutrients and organic C in soil runoff, and to calculate the enrichment rates and the cost of these losses. The treatments evaluated were: a soil with a crop, consisting of conventional tillage with one plowing + two harrowings (CT, minimum tillage with one chisel plowing + one harrowing (MT, and no tillage (NT; and b bare soil: one plowing + two harrowings (BS. In CT, MT, and NT, black oat, soybean, vetch, corn, turnip, and black beans were cultivated. Over the 15 years, 15.5 Mg ha-1 of limestone, 525 kg ha-1 of N (urea, 1,302 kg ha-1 of P2O5 (triple superphosphate, and 1,075 kg ha-1 of K2O (potassium chloride were used in the soil. The P, K, Ca, Mg, and organic C contents in the soil were determined and also the P, K, Ca, and Mg sediments in the runoff water. From these contents, the total losses, the enrichment rates (ER, and financial losses were calculated. The NT increased the P, K, and organic C contents in the topsoil. The nutrients and organic C content in the runoff from NT was greater than from CT, showing that NT was not a fully conservationist practice for soil. The linear model y = a + bx fit the data within the level of significance (p≤0.01 when the values of P, K, and organic C in the sediments from erosion were related to those values in the soil surface layer. The nutrient and organic C contents were higher in the sediments from erosion than in the soil where the erosion originated, generating values of ER>1 for P, K, and organic C. The value of the total losses

  15. Experimental evidence of nitrogen control on pCO2 in phosphorus-enriched humic and clear coastal lagoon waters

    Directory of Open Access Journals (Sweden)

    Roberta Bittencourt Peixoto

    2013-02-01

    Full Text Available Natural and human-induced controls on carbon dioxide (CO2 in tropical waters may be very dynamic (over time and among or within ecosystems considering the potential role of warmer temperatures intensifying metabolic responses and playing a direct role on the balance between photosynthesis and respiration. The high magnitude of biological processes at low latitudes following eutrophication by nitrogen (N and phosphorus (P inputs into inland waters may be a relevant component of the C cycle, showing controls on partial pressure of CO2 (pCO2 that are still poorly understood. Here we assessed the strength of N control on pCO2 in P-enriched humic and clear coastal lagoons waters, using four experimental treatments in microcosms: control (no additional nutrients and three levels of N additions coupled to P enrichments. In humic coastal lagoon waters, a persistent CO2 supersaturation was reported in controls and all nutrient-enriched treatments, ranging from 24-fold to fourfold the atmospheric equilibrium value. However, both humic and clear coastal lagoon waters only showed significant decreases in pCO2 in relation to the controlled microcosms in the two treatments with higher N addition levels. Additionally, clear coastal lagoon water microcosms showed a shift from CO2 sources to CO2 sinks, in relation to the atmosphere. Only in the two more N-enriched treatments did pCO2 substantially decrease, from 650 µatm in controls and less N-enriched treatments to 10 µatm in more N-enriched microcosms. Humic substrates and N inputs can modulate pCO2 even in P-enriched coastal lagoon waters, thereby being important drivers on CO2 outgassing from inland waters.

  16. Removal of heavy metals from water with forest based materials

    Science.gov (United States)

    James D. McSweeny; Roger M. Rowell; George C. Chen; Thomas L. Eberhardt; Soo-Hong Min

    2006-01-01

    For 1.5 to 2.5 billion people in the world, clean water is a critical issue (Lepkowski 1999). In the U.S., it is estimated that 90% of all Americans live within 10 miles of a body of contaminated water (Hogue, 2000). The development of filters to clean our water supply is big business. It is estimated that global spending on filtration (including dust collectors, air...

  17. Removal of radioactive materials and heavy metals from water using magnetic resin

    Science.gov (United States)

    Kochen, Robert L.; Navratil, James D.

    1997-01-21

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

  18. Effects of sulfate on heavy metal release from iron corrosion scales in drinking water distribution system.

    Science.gov (United States)

    Sun, Huifang; Shi, Baoyou; Yang, Fan; Wang, Dongsheng

    2017-05-01

    Trace heavy metals accumulated in iron corrosion scales within a drinking water distribution system (DWDS) could potentially be released to bulk water and consequently deteriorate the tap water quality. The objective of this study was to identify and evaluate the release of trace heavy metals in DWDS under changing source water conditions. Experimental pipe loops with different iron corrosion scales were set up to simulate the actual DWDS. The effects of sulfate levels on heavy metal release were systemically investigated. Heavy metal releases of Mn, Ni, Cu, Pb, Cr and As could be rapidly triggered by sulfate addition but the releases slowly decreased over time. Heavy metal release was more severe in pipes transporting groundwater (GW) than in pipes transporting surface water (SW). There were strong positive correlations (R 2  > 0.8) between the releases of Fe and Mn, Fe and Ni, Fe and Cu, and Fe and Pb. When switching to higher sulfate water, iron corrosion scales in all pipe loops tended to be more stable (especially in pipes transporting GW), with a larger proportion of stable constituents (mainly Fe 3 O 4 ) and fewer unstable compounds (β-FeOOH, γ-FeOOH, FeCO 3 and amorphous iron oxides). The main functional iron reducing bacteria (IRB) communities were favorable for the formation of Fe 3 O 4 . The transformation of corrosion scales and the growth of sulfate reducing bacteria (SRB) accounted for the gradually reduced heavy metal release with time. The higher metal release in pipes transporting GW could be due to increased Fe 6 (OH) 12 CO 3 content under higher sulfate concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. assessment of heavy metals concentration in drinking water ...

    African Journals Online (AJOL)

    userpc

    chemical industries and dissolved gases (Jimoh and Umar 2015). Water contaminated by sewage is estimated to kill about two million children every year (Harrison, 1992). The availability of good quality water is an indispensable feature for preventing diseases and improving quality of life (Adefemi and. Awokunmi 2007).

  20. DYNAMIC DEUTERIUM ENRICHMENT IN COMETARY WATER VIA ELEY–RIDEAL REACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yunxi; Giapis, Konstantinos P., E-mail: giapis@cheme.caltech.edu [Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125 (United States)

    2017-01-20

    The deuterium-to-hydrogen ratio (D/H) in water found in the coma of Jupiter family comet (JFC) 67P/Churyumov–Gerasimenko was reported to be (5.3 ± 0.7) × 10{sup −4}, the highest among comets and three times the value for other JFCs with an ocean-like ratio. This discrepancy suggests the diverse origins of JFCs and clouds the issue of the origin of Earth’s oceanic water. Here we demonstrate that Eley–Rideal reactions between accelerated water ions and deuterated cometary surface analogs can lead to instantaneous deuterium enrichment in water scattered from the surface. The reaction proceeds with H{sub 2}O{sup +} abstracting adsorbed D atoms, forming an excited H{sub 2}DO* state, which dissociates subsequently to produce energetic HDO. Hydronium ions are also produced readily by the abstraction of H atoms, consistent with H{sub 3}O{sup +} detection and abundance in various comets. Experiments with water isotopologs and kinematic analysis on deuterated platinum surfaces confirmed the dynamic abstraction mechanism. The instantaneous fractionation process is independent of the surface temperature and may operate on the surface of cometary nuclei or dust grains, composed of deuterium-rich silicates and carbonaceous chondrites. The requisite energetic water ions have been detected in the coma of 67P in two populations. This dynamic fractionation process may temporarily increase the water D/H ratio, especially as the comet gets closer to the Sun. The magnitude of the effect depends on the water ion energy-flux and the deuterium content of the exposed cometary surfaces.

  1. Dynamic Deuterium Enrichment in Cometary Water via Eley-Rideal Reactions

    Science.gov (United States)

    Yao, Yunxi; Giapis, Konstantinos P.

    2017-01-01

    The deuterium-to-hydrogen ratio (D/H) in water found in the coma of Jupiter family comet (JFC) 67P/Churyumov-Gerasimenko was reported to be (5.3 ± 0.7) × 10-4, the highest among comets and three times the value for other JFCs with an ocean-like ratio. This discrepancy suggests the diverse origins of JFCs and clouds the issue of the origin of Earth’s oceanic water. Here we demonstrate that Eley-Rideal reactions between accelerated water ions and deuterated cometary surface analogs can lead to instantaneous deuterium enrichment in water scattered from the surface. The reaction proceeds with H2O+ abstracting adsorbed D atoms, forming an excited H2DO* state, which dissociates subsequently to produce energetic HDO. Hydronium ions are also produced readily by the abstraction of H atoms, consistent with H3O+ detection and abundance in various comets. Experiments with water isotopologs and kinematic analysis on deuterated platinum surfaces confirmed the dynamic abstraction mechanism. The instantaneous fractionation process is independent of the surface temperature and may operate on the surface of cometary nuclei or dust grains, composed of deuterium-rich silicates and carbonaceous chondrites. The requisite energetic water ions have been detected in the coma of 67P in two populations. This dynamic fractionation process may temporarily increase the water D/H ratio, especially as the comet gets closer to the Sun. The magnitude of the effect depends on the water ion energy-flux and the deuterium content of the exposed cometary surfaces.

  2. Treatment of process water containing heavy metals with a two-stage electrolysis procedure in a membrane electrolysis cell

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, R.; Krebs, P. [Technische Universitaet Dresden, Institut fuer Siedlungs- und Industriewasserwirtschaft, Mommsenstrasse 13, 01062 Dresden (Germany); Seidel, H. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Department Bioremediation, Permoserstrasse 15, D-04318 Leipzig (Germany); Morgenstern, P. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Department Analytik, Permoserstrasse 15, D-04318 Leipzig (Germany); Foerster, H.J.; Thiele, W. [Eilenburger Elektrolyse- und Umwelttechnik GmbH, Ziegelstrasse 2, D-04838 Eilenburg (Germany)

    2005-04-01

    pH sank to 1.7. All heavy metals contained, with the exception of Zn, were removed to levels below the German limits for discharging industrial wastewaters into the receiving water. Moreover, the metal-depleted and acid-enriched process waters could be returned to the leaching process, hence reducing the output of wastewater. The results indicated that heavy metals could be removed from acidic process waters by two-stage electrochemical treatment to a large extent. However, to improve the efficiency of metal removal and to establish the electrochemical treatment in practice, further work is necessary to optimize the operation of the process with respect to current density, energy consumption, discharging of metal precipitates deposited in the electrode chambers and preventing membrane clogging. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  3. AN INDEXING APPROACH FOR THE ASSESSMENT OF HEAVY METALS IN DRINKING WATER PRODUCED BY MAURITANIAN WATER TREATMENT PLANT

    OpenAIRE

    Brahim Baba Aloueimine*; Mohamed Ould Kankou; Driss Belghyti

    2017-01-01

    In the present work, the assessment of drinking water quality was carried out through a monitoring of heavy metals in the treated and consumed waters in the city of Nouakchott (Mauritania). Monthly sampling was conducted for a period of 24 months between January 2012 and December 2013. Nine parameters were evaluated: pH, T (°C), Turbidity (NTU), Al, Fe, Cu, Mn, Al2(SO4)3 and CaO. Indexing approaches have been applied by calculating the Heavy Metal Pollution Index (HPI) and Metal Index (MI) fo...

  4. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    Directory of Open Access Journals (Sweden)

    Mustafa Şahin Dündar

    2012-06-01

    Full Text Available Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, highest mean levels of copper in supernatants of plating and textile industries were observed as 377,18 ng ml-1, respectively 103 ng ml-1 lead and 963,6 ng ml-1 nickel in plating industry, 1068,2 ng ml-1 zinc and 14557,1 ng ml-1 chromium in plating and leather industries were determined.

  5. Water-soluble organophosphorus reagents for mineralization of heavy metals.

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K. L.

    1999-02-26

    In this report, we have described the principal stages of a two-step process for the in-situ stabilization of actinide ions in the environment. The combination of cation exchange and mineralization appears likely to provide a long-term solution to environments contaminated with heavy metals. Relying on a naturally occurring sequestering agent has obvious potential advantages from a regulatory standpoint. There are additional aspects of this technology requiring further elucidation, including the demonstration of the effect of these treatment protocols on the geohydrology of soil columns, further examination of the influence of humates and other colloidal species on cation uptake, and microbiological studies of phytate hydrolysis. We have learned during the course of this investigation that phytic acid is potentially available in large quantities. In the US alone, phytic acid is produced at an annual rate of several hundred thousand metric tons as a byproduct of fermentation processes (11). This material presently is not isolated for use. Instead, most of the insoluble phyate (as phytin) is being recycled along with the other solid fermentation residues for animal feed. This material is in fact considered undesirable in animal feed. The details of possible separation processes for phytate from these residues would have to be worked out before this untapped resource would be available for application to heavy metal sequestration. The results described emphasize the behavior of actinide and trivalent lanthanide metal ions, as these species are of primary interest to the Department of Energy for the cleanup of the former nuclear weapons production complex. While the specific demonstration includes this limited selection of metal ions, the technique should be readily applicable to any class of metal ions that form insoluble phosphate compounds under appropriate conditions. Further, though this demonstration has been conducted in the pH 5-8 range, it is conceivable that

  6. Design of Heavy Metals Monitoring System in Water Based on WSN and GPRS

    Directory of Open Access Journals (Sweden)

    Ke Lin

    2014-04-01

    Full Text Available In order to realize the real-time monitoring of heavy metals in water environment, a new type of heavy metal monitoring system was developed. The system was composed of monitoring terminal, gateway, GPRS network and upper computer monitoring center. The system detected the heavy metal ion concentrations by ion-selective electrode array and came into the system error automatic compensation method in the detection process. The collecting data was transported to the monitoring center through the cooperation between the wireless sensor network constituted by CC2530 and General Packet Radio Service network. The test result shows that the system can increased precision dramatically and strengthens the real-time transmission capacity effectively. The system is reliable in transmission, high real-time performance, flexible in networking and can be applied to continuous remote monitoring of heavy metals pollution.

  7. Eliminating Heavy Metals from Water with NanoSheet Minerals as Adsorbents

    Directory of Open Access Journals (Sweden)

    Shaoxian Song

    2017-12-01

    Full Text Available Heavy metals usually referred to those with atomic weights ranging from 63.5 to 200.6. Because of natural-mineral dissolution and human activities such as mining, pesticides, fertilizer, metal planting and batteries manufacture, etc., these heavy metals, including zinc, copper, mercury, lead, cadmium and chromium have been excessively released into water courses, like underground water, lake and river, etc. The ingestion of the heavy metals-contaminated water would raise serious health problems to human beings even at a low concentration. For instance, lead can bring human beings about barrier to the normal function of kidney, liver and reproductive system, while zinc can cause stomach cramps, skin irritations, vomiting and anemia. Mercury is a horrible neurotoxin that may result in damages to the central nervous system, dysfunction of pulmonary and kidney, chest and dyspnea. Chromium (VI has been proved can cause many diseases ranging from general skin irritation to severe lung carcinoma. Accordingly, the World Health Organization announced the maximum contaminant levels (MCL for the heavy metals in drinking water. There are numerous processes for eliminating heavy metals from water in order to provide citizens safe drinking water, including precipitation, adsorption, ion exchange, membrane separation and biological treatment, etc. Adsorption is considered as a potential process for deeply removing heavy metals, in which the selection of adsorbents plays a predominant role. Nano-sheet minerals as the adsorbents are currently the hottest researches in the field. They are obtained from layered minerals, such as montmorillonite, graphite and molybdenite, through the processing of intercalation, electrochemical and mechanical exfoliation, etc. Nano-sheet minerals are featured by their large specific surface area, relatively low costs and active adsorbing sites, leading to be effective and potential adsorbents for heavy metals removal from water

  8. PHYSICOCHEMICAL PROPERTIES OF THE WATER DEPLETED OF HEAVY ISOTOPES

    Directory of Open Access Journals (Sweden)

    Vladislav V. Goncharuk

    2012-06-01

    Full Text Available Data on physicochemical properties of the light water (deuterium concentration is reduced to the ratio D/H = 4 ppm and that of the isotope of oxygen 18 – to the ratio 18O/16O = 750 ppm have been obtained. They include the melting and boiling points, kinematic viscosity, density, the spin-spin proton relaxation time, self-diffusion coefficients, and the small-angle laser light scattering. An explanation was proposed for the detected significant changes of the light water as compared with the high-resistivity water having geochemically ordinary isotope composition.

  9. Effects of soil enrichment, watering and seedling age on establishment of Mediterranean woody species

    Science.gov (United States)

    Siles, Gemma; Rey, Pedro J.; Alcántara, Julio M.; Bastida, Jesús M.; Herreros, Jose L.

    2010-07-01

    Vegetation restoration in strongly degraded lands has inherent limitations. Among the most relevant limitations in Mediterranean Mountains are severe drought and stressful levels of irradiance during summer. Thus, it is common that seedlings planted in open ground incur high rates of early mortality. In the context of a project of restoration of a burned area in Southern Spain, we evaluate the efficiency of watering and enrichment with native soil, and the influence of seedling age on survival and growth of 9 late-successional tall shrubs and trees planted in open ground. We also explore how small-scale variation in environmental variables relates to establishment success. Our results show an overall positive effect of watering on the survival of planted seedlings, while the effects of enrichment with native soil and age of planted seedlings were species-specific. Seedling establishment varied markedly with the presence of ravines, which duplicated seedling survival. This suggests that ravines may be more easily restored, improving their role as corridors in landscape designs of restoration. Independently of the treatment applied, Rosa sp. and Crataegus monogyna, both fleshy-fruited species, had the highest rates of establishment. In conclusion, this study shows the viability of low aggressive restoration techniques to assist vegetation recovery in fire-degraded environments. Specifically, watering and planting in ravines should be considered where restoration practices are applied in areas lacking vegetation cover. Some species highly attractive for animal dispersers and of easy establishment ( Rosa sp. and Crataegus sp.) could be used to enhance spontaneous regeneration within and beyond corridors through increasing seed attraction and dissemination.

  10. Effect of the foliar enrichment and herbicides on maize and associated weeds irrigated with drainage water

    Directory of Open Access Journals (Sweden)

    Roshdy M.H. Tagour

    2017-12-01

    Full Text Available A two-year field experiment was conducted during summer seasons of 2013 and 2014, which were irrigated by drainage water which belong to salinity class (C3S1 to C4S2, to study the effect of the foliar enrichment namely (Anti-stress and weed management treatments (some pre and post-emergence herbicides and two-hand hoeing on maize growth, yield, yield components and chemical composition of maize grains and associated weeds (Portulaca oleracea, Amaranthus retroflexus and Echinochloa colonum. The results illustrated that application of the foliar enrichment enhanced the dry weight of weeds and increased maize growth characters, yield and yield components and total crude protein and total oil percentage of grain maize, as compared with untreated treatment. All weed management treatments caused a significant reduction in total dry weight of weeds at 60 and 80 days after sowing in both seasons. Two-hand hoeing treatment exerted the highest decrease in total dry weight of weeds followed by metribuzin, oxadiagyl, fluroxypyr and bentazon, respectively at 60 and 80 days after sowing compared with other weed management treatments. While, the highest values of maize growth, yield, yield components and maize grains' content of protein and oil was obtained with two-hand hoeing followed by metribuzin, oxadiagyl, fluroxypyr and bentazon, respectively. While, two hands hoeing produced the maximum values of leaf area, ear length, the weight of kernels plant−1, but applying of metribuzin treatment gave the highest values of total oil percentage of grain maize when the foliar enrichment was used.

  11. Removal of Heavy Metals from Drinking Water by Magnetic Carbon Nanostructures Prepared from Biomass

    Directory of Open Access Journals (Sweden)

    Muhammad Muneeb Ur Rahman Khattak

    2017-01-01

    Full Text Available Heavy metals contamination of drinking water has significant adverse effects on human health due to their toxic nature. In this study a new adsorbent, magnetic graphitic nanostructures were prepared from watermelon waste. The adsorbent was characterized by different instrumental techniques (surface area analyzer, FTIR, XRD, EDX, SEM, and TG/DTA and was used for the removal of heavy metals (As, Cr, Cu, Pb, and Zn from water. The adsorption parameters were determined for heavy metals adsorption using Freundlich and Langmuir isotherms. The adsorption kinetics and effect of time, pH, and temperature on heavy metal ions were also determined. The best fits were obtained for Freundlich isotherm. The percent adsorption showed a decline at high pH. Best fit was obtained with second-order kinetics model for the kinetics experiments. The values of ΔH° and ΔG° were negative while that of ΔS° was positive. The prepared adsorbent has high adsorption capacities and can be efficiently used for the removal of heavy metals from water.

  12. Phytoremediation of heavy metal-contaminated water and sediment by eleocharis acicularis

    Energy Technology Data Exchange (ETDEWEB)

    Sakakibara, Masayuki; Ha, Nguyen Thi Hoang [Graduate School of Science and Engineering, Ehime University, Matsuyama (Japan); Ohmori, Yuko [Graduate School of Science and Engineering, Ehime University, Matsuyama (Japan); Taisei Kiso Sekkei Co., Ltd., Tokyo (Japan); Sano, Sakae [Faculty of Education, Ehime University, Matsuyama (Japan); Sera, Koichiro [Cyclotron Center, Iwate Medical University, Takizawa-mura (Japan)

    2011-08-15

    Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log-linear fashion. The bioconcentration factor for these elements decreases log-linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Physical and water properties of selected Polish heavy soils of various origins

    Directory of Open Access Journals (Sweden)

    Kaczmarek Zbigniew

    2015-12-01

    Full Text Available The paper presents the characteristics of selected physical, chemical, and water properties of four mineral arable soils characterized with heavy and very heavy texture. Soil samples from genetic horizons of black earths from areas near Kętrzyn, Gniew and Kujawy, and alluvial soils from Żuławy were used. The following properties were determined in the samples of undisturbed and disturbed structure: texture, particle density, bulk density, porosity, natural and hygroscopic moistures, maximal hygroscopic capacity, saturated hydraulic conductivity, potential of water bonding in soil, total and readily available water, total retention in the horizon of 0–50 cm, drainage porosity, content of organic carbon and total nitrogen Parent rocks of these soils were clays, silts and loams of various origin. High content of clay fraction strongly influenced the values of all the analyzed properties. All the examined soils had high content of organic carbon and total nitrogen and reaction close to neutral or alkaline. High content of mineral and organic colloids and, what follows, beneficial state of top horizons’ structure, determined – apart from heavy texture – low soil bulk density and high porosity. The investigated soils were characterized by high field water capacity and wide scopes of total and readily available water. The saturated hydraulic conductivity was low and characteristic to heavy mineral arable soils. The parameter which influenced the variability of analyzed parameters most was texture.

  14. System-Aware Smart Network Management for Nano-Enriched Water Quality Monitoring

    Directory of Open Access Journals (Sweden)

    B. Mokhtar

    2016-01-01

    Full Text Available This paper presents a comprehensive water quality monitoring system that employs a smart network management, nano-enriched sensing framework, and intelligent and efficient data analysis and forwarding protocols for smart and system-aware decision making. The presented system comprises two main subsystems, a data sensing and forwarding subsystem (DSFS, and Operation Management Subsystem (OMS. The OMS operates based on real-time learned patterns and rules of system operations projected from the DSFS to manage the entire network of sensors. The main tasks of OMS are to enable real-time data visualization, managed system control, and secure system operation. The DSFS employs a Hybrid Intelligence (HI scheme which is proposed through integrating an association rule learning algorithm with fuzzy logic and weighted decision trees. The DSFS operation is based on profiling and registering raw data readings, generated from a set of optical nanosensors, as profiles of attribute-value pairs. As a case study, we evaluate our implemented test bed via simulation scenarios in a water quality monitoring framework. The monitoring processes are simulated based on measuring the percentage of dissolved oxygen and potential hydrogen (PH in fresh water. Simulation results show the efficiency of the proposed HI-based methodology at learning different water quality classes.

  15. Detection of heavy metals in water using dye nano-complexants and a polymeric film.

    Science.gov (United States)

    Hadar, Hodayah Abuhatzira; Bulatov, Valery; Dolgin, Bella; Schechter, Israel

    2013-09-15

    An optical analytical method, based on complexation reactions of organic azo-dyes with heavy metals, is proposed. It is based on a specially designed polymeric film that when submerged in water contaminated with heavy metals it changes its color. The azo-dyes are injected into the tested water, resulting in formation of nano-particles of insoluble complexes. The polymeric film embeds and dissolves these nano-particles and thus allows for spectral and/or visual analysis. This film consists of a PVC polymeric skeleton and an organic solvent, bis(2-ethylhexyl)phthalate, which possesses high affinity to the heavy metal nano-complexes. The method was exemplified for Cd, Ni and Co ions. The method is sensitive in the sub-ppm range. The mechanism and kinetics of the film coloration were reported. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Adsorption of heavy metals in waste water using biological materials

    Directory of Open Access Journals (Sweden)

    Candelaria Tejada-Tovar

    2015-01-01

    Full Text Available Biosorption is a process that allows active or passive uptake of metal ions due to the property that different living or dead biomass have to bind and accumulate these pollutants by different mechanisms. The application of low-cost materials obtained from different biomass from microbial flora, agro-industrial waste and algae has been investigated to replace the use of conventional methods for the removal of contaminants such as heavy metals. Some of the metals of greatest impact to the environment due to its high toxicity and difficult to remove are chromium, nickel, cadmium, lead, and mercury. In this paper, an overview of adsorption as an alternative process for the removal of contaminants in solution and biomass commonly used in these processes, as well as some of the modifications made to improve the efficiency of adsorption of these materials is presented. It was concluded that the use of adsorption in the removal of pollutants in aqueous solution using waste biomass is applicable to these decontamination processes avoiding subsequent problems such as the generation of chemical sludge, and generating an alternative to use materials considered as waste. It is further identified that such factors as the pH of the solution, particle size, temperature, and concentration of metal effect on the process.

  17. Effect of administration of water enriched in O2 by injection or electrolysis on transcutaneous oxygen pressure in anesthetized pigs.

    Science.gov (United States)

    Charton, Antoine; Péronnet, François; Doutreleau, Stephane; Lonsdorfer, Evelyne; Klein, Alexis; Jimenez, Liliana; Geny, Bernard; Diemunsch, Pierre; Richard, Ruddy

    2014-01-01

    Oral administration of oxygenated water has been shown to improve blood oxygenation and could be an alternate way for oxygen (O2) supply. In this experiment, tissue oxygenation was compared in anesthetized pigs receiving a placebo or water enriched in O2 by injection or a new electrolytic process. Forty-two pigs randomized in three groups received either mineral water as placebo or water enriched in O2 by injection or the electrolytic process (10 mL/kg in the stomach). Hemodynamic parameters, partial pressure of oxygen in the arterial blood (PaO2), skin blood flow, and tissue oxygenation (transcutaneous oxygen pressure, or TcPO2) were monitored during 90 minutes of general anesthesia. Absorption and tissue distribution of the three waters administered were assessed using dilution of deuterium oxide. Mean arterial pressure, heart rate, PaO2, arteriovenous oxygen difference, and water absorption from the gut were not significantly different among the three groups. The deuterium to protium ratio was also similar in the plasma, skin, and muscle at the end of the protocol. Skin blood flow decreased in the three groups. TcPO2 slowly decreased over the last 60 minutes of the experiment in the three groups, but when compared to the control group, the values remained significantly higher in animals that received the water enriched in O2 by electrolysis. In this protocol, water enriched in O2 by electrolysis lessened the decline of peripheral tissue oxygenation. This observation is compatible with the claim that the electrolytic process generates water clathrates which trap O2 and facilitate O2 diffusion along pressure gradients. Potential applications of O2-enriched water include an alternate method of oxygen supply.

  18. Effect of administration of water enriched in O2 by injection or electrolysis on transcutaneous oxygen pressure in anesthetized pigs

    Science.gov (United States)

    Charton, Antoine; Péronnet, François; Doutreleau, Stephane; Lonsdorfer, Evelyne; Klein, Alexis; Jimenez, Liliana; Geny, Bernard; Diemunsch, Pierre; Richard, Ruddy

    2014-01-01

    Background Oral administration of oxygenated water has been shown to improve blood oxygenation and could be an alternate way for oxygen (O2) supply. In this experiment, tissue oxygenation was compared in anesthetized pigs receiving a placebo or water enriched in O2 by injection or a new electrolytic process. Methods Forty-two pigs randomized in three groups received either mineral water as placebo or water enriched in O2 by injection or the electrolytic process (10 mL/kg in the stomach). Hemodynamic parameters, partial pressure of oxygen in the arterial blood (PaO2), skin blood flow, and tissue oxygenation (transcutaneous oxygen pressure, or TcPO2) were monitored during 90 minutes of general anesthesia. Absorption and tissue distribution of the three waters administered were assessed using dilution of deuterium oxide. Results Mean arterial pressure, heart rate, PaO2, arteriovenous oxygen difference, and water absorption from the gut were not significantly different among the three groups. The deuterium to protium ratio was also similar in the plasma, skin, and muscle at the end of the protocol. Skin blood flow decreased in the three groups. TcPO2 slowly decreased over the last 60 minutes of the experiment in the three groups, but when compared to the control group, the values remained significantly higher in animals that received the water enriched in O2 by electrolysis. Conclusions In this protocol, water enriched in O2 by electrolysis lessened the decline of peripheral tissue oxygenation. This observation is compatible with the claim that the electrolytic process generates water clathrates which trap O2 and facilitate O2 diffusion along pressure gradients. Potential applications of O2-enriched water include an alternate method of oxygen supply. PMID:25210438

  19. Study on the Effects of Irrigation with Reclaimed Water on the Content and Distribution of Heavy Metals in Soil

    Directory of Open Access Journals (Sweden)

    Shibao Lu

    2016-03-01

    Full Text Available Reclaimed water is an important resource for irrigation, and exploration in making full use of it is an important way to alleviate water shortage. This paper analyzes the effects of irrigation with reclaimed water through field trials on the content and distribution of heavy metals in both tomatoes and the soil. By exploring the effects of reclaimed water after secondary treatment on the content and distribution characteristics of heavy metals in tomatoes and the heavy metal balance in the soil-crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of reclaimed water for irrigation varies. Reclaimed water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the national standard, which indicates that the vegetables irrigated with reclaimed water during their growth turn out to be free of pollutants. The heavy metals brought into the soil by reclaimed water are less than that taken away by the crops. The input and output quantities have only small effects on the heavy metal balance in the soil. This paper provides a reference for the evaluation and safety control of irrigation with reclaimed water.

  20. Possible ancient giant basin and related water enrichment in the Arabia Terra province, Mars

    Science.gov (United States)

    Dohm, J.M.; Barlow, N.G.; Anderson, R.C.; Williams, J.-P.; Miyamoto, H.; Ferris, J.C.; Strom, R.G.; Taylor, G.J.; Fairen, A.G.; Baker, V.R.; Boynton, W.V.; Keller, J.M.; Kerry, K.; Janes, D.; Rodriguez, J.A.P.; Hare, T.M.

    2007-01-01

    A circular albedo feature in the Arabia Terra province was first hypothesized as an ancient impact basin using Viking-era information. To test this unpublished hypothesis, we have analyzed the Viking era-information together with layers of new data derived from the Mars Global Surveyor (MGS) and Mars Odyssey (MO) missions. Our analysis indicates that Arabia Terra is an ancient geologic province of Mars with many distinct characteristics, including predominantly Noachian materials, a unique part of the highland-lowland boundary, a prominent paleotectonic history, the largest region of fretted terrain on the planet, outflow channels with no obvious origins, extensive exposures of eroded layered sedimentary deposits, and notable structural, albedo, thermal inertia, gravity, magnetic, and elemental signatures. The province also is marked by special impact crater morphologies, which suggest a persistent volatile-rich substrate. No one characteristic provides definitive answers to the dominant event(s) that shaped this unique province. Collectively the characteristics reported here support the following hypothesized sequence of events in Arabia Terra: (1) an enormous basin, possibly of impact origin, formed early in martian history when the magnetic dynamo was active and the lithosphere was relatively thin, (2) sediments and other materials were deposited in the basin during high erosion rates while maintaining isostatic equilibrium, (3) sediments became water enriched during the Noachian Period, and (4) basin materials were uplifted in response to the growth of the Tharsis Bulge, resulting in differential erosion exposing ancient stratigraphic sequences. Parts of the ancient basin remain water-enriched to the present day. ?? 2007 Elsevier Inc. All rights reserved.

  1. Phytoremediation potential of some heavy metals by water hyacinth ...

    African Journals Online (AJOL)

    The phytoremediation potential of water hyacinth plant (Eichhornia crassipes) was investigated on some metals. The plants were grown for 7 days each in phytoremediation tanks containing a solution of 100 ppm concentration of either Potassium (K), Sodium (Na), Zinc (Zn), Lead (Pb), Iron (Fe), Cadmium (Cd), Magnesium ...

  2. Physicochemical Characteristics and Heavy Metal Levels in Water ...

    African Journals Online (AJOL)

    From the findings, there is need to protect the quality of the water systems for recreational, industrial and domestic uses. It is hoped that the result of this study would help the Delta State government and other interest groups to maintain existing projects, plan and also to execute properly future development programs in the ...

  3. Simulation of heavy metal contamination of fresh water bodies: Toxic ...

    African Journals Online (AJOL)

    The results show that ZnSO4 was significantly toxic to the fish only after 96 hours. Co-contamination of the water with both toxicants was found to ameliorate the toxic effects of ZnSO4 significantly. The metal chelating property of glyphosate may be responsible for the observed attenuation of toxicity in the fish in Group ...

  4. Physicochemical Characteristics and Heavy Metal Levels in Water ...

    African Journals Online (AJOL)

    MICHAEL

    selected for study were well distributed and possessed similar geology, climate, soil, and vegetation characteristics. Studies on the water samples collected from ... geology, climates, soil, vegetation and drainage characteristics (Atakpo et al., 2000; ..... hydrologic balance of the watersheds. This balance was a function of the ...

  5. determination of the level of some heavy metals in water collected

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. Industrial effluents discharged into the environment pose a serious threat to our agricultural products and health. In view of this, levels of some heavy metals, Zn, Pb, Cr, Cu, Ni, Co, Ag, Fe and. Mn were determined in water samples collected from two pollution prone areas around Kano. (Sharada and Bompai ...

  6. Measures to diminish leaching of heavy metals to surface waters from agricultural soils

    NARCIS (Netherlands)

    Schipper, P.N.M.; Bonten, L.T.C.; Plette, A.C.C.; Moolenaar, S.W.

    2008-01-01

    Historical accumulation of heavy metals in agricultural soils has caused an increased leaching to shallow groundwater in the Netherlands. The elevated concentrations of metals like copper and zinc in shallow groundwater, causes problems to meet target levels in surface waters. Important sources for

  7. Assessment of heavy metal residues in water, fish tissue and human ...

    African Journals Online (AJOL)

    MICHAEL HORSFALL

    www.ajol.info and www.bioline.org.br/ja. Assessment of heavy metal residues in water, fish tissue and human blood from Ubeji,. Warri, Delta State, Nigeria. 1. JOY F. AKINTUJOYE; 2CHIAKA I. ANUMUDU; *3HENRIETTA O. AWOBODE. 1Ecology and Environmental Biology Unit, Department of Zoology, University of Ibadan, ...

  8. Levels of heavy metals in Gubi dam water Bauchi, Nigeria | Wufem ...

    African Journals Online (AJOL)

    The distribution of heavy metals in Gubi Dam, Bauchi, Nigeria was studied covering the highest turbulent and non-turbulent flow periods. The average concentrations of iron, manganese, nickel, zinc, cobalt, chromium and cadmium were generally highest in filtrate water, whereas the concentrations of copper and lead were ...

  9. Heavy metal contamination in agricultural soils and water in Dar es ...

    African Journals Online (AJOL)

    USER

    contaminated soil, water and air (Zurera et al., 1989). As trace elements, some heavy metals e.g. copper, ... cadmium, copper, lead, nickel and zinc can cause deleterious health effects in humans (Reilly, 1991). ... manufacturing batteries, textile, steel, paints, food processing, abattoir, and electrical products. Msimbazi River ...

  10. Analysis of Removal Alternatives for the Heavy Water Components Test Reactor at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Owen, M.B. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1996-08-01

    This engineering study was developed to evaluate different options for decommissioning of the Heavy Water Components Test Reactor (HWCTR) at the Savannah River Site. This document will be placed in the DOE-SRS Area reading rooms for a period of 30 days in order to obtain public input to plans for the demolition of HWCTR.

  11. Heavy Metals in Water of Upper Kolo Creek – Bayelsa State, Nigeria ...

    African Journals Online (AJOL)

    Humans and aquatic inhabitants are affected by pollution which results in disruption of metabolic processes such as reproduction, development and growth of aquatic animals including fish. This study investigated the concentration of heavy metals in water and sediment obtained from upper kolo creek – Ogbia local ...

  12. Chemical and microstructural analyses for heavy metals removal from water media by ceramic membrane filtration.

    Science.gov (United States)

    Ali, Asmaa; Ahmed, Abdelkader; Gad, Ali

    2017-01-01

    This study aims to investigate the ability of low cost ceramic membrane filtration in removing three common heavy metals namely; Pb2+, Cu2+, and Cd2+ from water media. The work includes manufacturing ceramic membranes with dimensions of 15 by 15 cm and 2 cm thickness. The membranes were made from low cost materials of local clay mixed with different sawdust percentages of 0.5%, 2.0%, and 5.0%. The used clay was characterized by X-ray diffraction (XRD) and X-ray fluorescence analysis. Aqueous solutions of heavy metals were prepared in the laboratory and filtered through the ceramic membranes. The influence of the main parameters such as pH, initial driving pressure head, and concentration of heavy metals on their removal efficiency by ceramic membranes was investigated. Water samples were collected before and after the filtration process and their heavy metal concentrations were determined by chemical analysis. Moreover, a microstructural analysis using scanning electronic microscope (SEM) was performed on ceramic membranes before and after the filtration process. The chemical analysis results showed high removal efficiency up to 99% for the concerned heavy metals. SEM images approved these results by showing adsorbed metal ions on sides of the internal pores of the ceramic membranes.

  13. Heavy-duty diesel engine NO{sub x} reduction with nitrogen-enriched combustion air. Final CRADA report.

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, S.; Energy Systems

    2010-07-28

    The concept of engine emissions control by modifying intake combustion gas composition from that of ambient air using gas separation membranes has been developed during several programs undertaken at Argonne. These have led to the current program which is targeted at heavy-duty diesel truck engines. The specific objective is reduction of NO{sub x} emissions by the target engine to meet anticipated 2007 standards while extracting a maximum of 5 percent power loss and allowing implementation within commercial constraints of size, weight, and cost. This report includes a brief review of related past programs, describes work completed to date during the current program, and presents interim conclusions. Following a work schedule adjustment in August 2002 to accommodate problems in module procurement and data analysis, activities are now on schedule and planned work is expected to be completed in September, 2004. Currently, we believe that the stated program requirements for the target engine can be met, based upon extrapolation of the work completed. Planned project work is designed to experimentally confirm these projections and result in a specification for a module package that will meet program objectives.

  14. Determination of heavy metals concentration in drinking water resources of Aleshtar in 2009

    Directory of Open Access Journals (Sweden)

    mehdi karbasi

    2010-04-01

    Materials and Methods :This cross- sectional study was carried out to determine concentration of heavy metals including As, Pb,Cd, Cr, Hg, Zn in Aleshtar drinking water resources. twenty samples from five drinking water wells were systematiclly collected and carried to water lab. By use of express standard methods,samples were 10 times concentrated, then metals concentralion determined by AAP(WFX130 and data analyzed by SPSS and EXCELL soft wares. Results: The results showed that concentration average of Hg ,Zn and Cd was zero during the sampling and concentration average of As,Pb and Cr in drinking water wells were 0.0033, 0.0788 and 0.01 mg/l respectively. Conclusion: Findings indicated that concentration average of heavy metals in all studied drinking water wells were lower than standard limit and no significant difference was observed during 4 stages of sampling , consequently ,drinking water of the mentioned wells are not polluted to the heavy metals.

  15. Heavy Metals in Water and Sediment: A Case Study of Tembi River

    Directory of Open Access Journals (Sweden)

    Saeed Shanbehzadeh

    2014-01-01

    Full Text Available This study was carried out to examine heavy metals concentration in water and sediment of upstream and downstream of the entry of the sewage to the Tembi River, Iran. Samples were collected from upstream and downstream and were analyzed for Cd, Cr, Cu, Fe, Pb, Ni, and Zn by atomic absorption spectrophotometer. The results indicated that the average concentration of the metals in water and sediment on downstream was more than that of upstream. The comparison of the mean concentrations of heavy metals in water of the Tembi River with drinking water standards and those in the water used for agriculture suggests that the mean concentration of Cu and Zn lies within the standard range for drinking water and the mean concentration of Mn, Zn, and Pb lies within the standard range of agricultural water. The highest average concentration on downstream for Pb in water and for Mn in sediment was 1.95 and 820.5 ppm, respectively. Also, the lowest average concentration on upstream was identified for Cd in water and sediment 0.07 and 10 ppm, respectively. With regard to the results, it gets clear that using the water for recreational purposes, washing, and fishing is detrimental to human health and the environment.

  16. Heavy Metal Concentration in Drinking Water Sources Affected by Dredge Mine Operations of a Gold Mining Company in Ghana

    OpenAIRE

    Apori Ntiforo; Maxwell Anim-Gyampo; Frank K. Nyame

    2012-01-01

    The study assesses concentration of certain heavy metals in water sources affected by the operations of defunct dredged gold mine operations more than a decade to evaluate its quality as a source of drinking water. The concentration of heavy metals were determined from nine (9) surface water sampling points and three (3) boreholes in the Awusu-River basin in comparison with their maximum contaminant levels to assess their suitability as drinking water sources. Results obtained from the analys...

  17. Modeling Adsorption Kinetics (Bio-remediation of Heavy Metal Contaminated Water)

    Science.gov (United States)

    McCarthy, Chris

    My talk will focus on modeling the kinetics of the adsorption and filtering process using differential equations, stochastic methods, and recursive functions. The models have been developed in support of our interdisciplinary lab group which is conducting research into bio-remediation of heavy metal contaminated water via filtration through biomass such as spent tea leaves. The spent tea leaves are available in large quantities as a result of the industrial production of tea beverages. The heavy metals bond with the surfaces of the tea leaves (adsorption). Funding: CUNY Collaborative Incentive Research Grant.

  18. Heavy metal concentrations in water, sediment and fish from Izmit Bay, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Taymaz, K.; Yigit, V.; Ozbal, H.; Ceritoglu, A.; Mueftuegil, N.

    1984-01-01

    Mercury, cadmium and lead levels in water, sediment and fish samples from Izmit Bay, Turkey have been determined. Sampling and analysis methods are described. Variations of heavy metal concentrations from different sampling stations are discussed. Results indicate that the levels of mercury and cadmium were highest in the vicinity of a chlor-alkali plant while the highest concentration of lead was near a metallic pipe factory. The amounts of heavy metals found in the shoreline sediment samples were similar to those found in fish species from the bay.

  19. AN INDEXING APPROACH FOR THE ASSESSMENT OF HEAVY METALS IN DRINKING WATER PRODUCED BY MAURITANIAN WATER TREATMENT PLANT

    Directory of Open Access Journals (Sweden)

    Brahim Baba Aloueimine*

    2017-10-01

    Full Text Available In the present work, the assessment of drinking water quality was carried out through a monitoring of heavy metals in the treated and consumed waters in the city of Nouakchott (Mauritania. Monthly sampling was conducted for a period of 24 months between January 2012 and December 2013. Nine parameters were evaluated: pH, T (°C, Turbidity (NTU, Al, Fe, Cu, Mn, Al2(SO43 and CaO. Indexing approaches have been applied by calculating the Heavy Metal Pollution Index (HPI and Metal Index (MI for the assessment of influence of heavy metals on the overall quality of water. The obtained results for heavy metals are in good agreement with World Health Organization (WHO standards. Though the aluminum concentration remains in the limits set by WHO, yet it shows a major contribution in the indices. This has been verified by the statistical analysis which demonstrates fair correlations between aluminum, HPI (r = 0.9 and MI (r = 0.77. Aluminum showed the important influence of seasonal change in the year as well as the doses of reagents injected during the treatment process on the concentration of aluminum is detailed.

  20. Poultry litter-based activated carbon for removing heavy metal ions in water.

    Science.gov (United States)

    Guo, Mingxin; Qiu, Guannan; Song, Weiping

    2010-02-01

    Utilization of poultry litter as a precursor material to manufacture activated carbon for treating heavy metal-contaminated water is a value-added strategy for recycling the organic waste. Batch adsorption experiments were conducted to investigate kinetics, isotherms, and capacity of poultry litter-based activated carbon for removing heavy metal ions in water. It was revealed that poultry litter-based activated carbon possessed significantly higher adsorption affinity and capacity for heavy metals than commercial activated carbons derived from bituminous coal and coconut shell. Adsorption of metal ions onto poultry litter-based carbon was rapid and followed Sigmoidal Chapman patterns as a function of contact time. Adsorption isotherms could be described by different models such as Langmuir and Freundlich equations, depending on the metal species and the coexistence of other metal ions. Potentially 404 mmol of Cu2+, 945 mmol of Pb2+, 236 mmol of Zn2+, and 250-300 mmol of Cd2+ would be adsorbed per kg of poultry litter-derived activated carbon. Releases of nutrients and metal ions from litter-derived carbon did not pose secondary water contamination risks. The study suggests that poultry litter can be utilized as a precursor material for economically manufacturing granular activated carbon that is to be used in wastewater treatment for removing heavy metals.

  1. Thermophysical properties of saturated light and heavy water for Advanced Neutron Source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor`s nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300{degrees}C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250{degrees}C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  2. Thermophysical properties of saturated light and heavy water for advanced neutron source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor's nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300[degrees]C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250[degrees]C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  3. Design dopamine-modified polypropylene fibers towards removal of heavy metal ions from water

    Directory of Open Access Journals (Sweden)

    K. Liu

    2017-04-01

    Full Text Available A simple approach to preparing dopamine-modified polypropylene fibers with a controllable polydopamine amount is supplied. By the dopamine modification, the hydrophobic polypropylene fibers have been changed into hydrophilic. The hydrophilicity can be improved by increasing the amount of polydopamine, as revealed by the contact angle evolutions. The hydrophilic dopamine-modified polypropylene fibers can rapidly and effectively remove copper and lead ions in water. Moreover, the performance of removing heavy metals is prominently improved as the polydopamine amount increases. This is because the polydopamine introduction can supply many available sites for adsorbing heavy metal ions, as revealed by theoretical simulation results. These results are crucial in future engineering fiber filters towards efficiently removing heavy metal ions using dopamine-modified polypropylene fibers.

  4. Design dopamine-modified polypropylene fibers towards removal of heavy metal ions from water

    Science.gov (United States)

    Liu, K.; Zhou, N. Y.; Xie, C. X.; Mou, B.; Ai, Y. N.

    2017-04-01

    A simple approach to preparing dopamine-modified polypropylene fibers with a controllable polydopamine amount is supplied. By the dopamine modification, the hydrophobic polypropylene fibers have been changed into hydrophilic. The hydrophilicity can be improved by increasing the amount of polydopamine, as revealed by the contact angle evolutions. The hydrophilic dopamine-modified polypropylene fibers can rapidly and effectively remove copper and lead ions in water. Moreover, the performance of removing heavy metals is prominently improved as the polydopamine amount increases. This is because the polydopamine introduction can supply many available sites for adsorbing heavy metal ions, as revealed by theoretical simulation results. These results are crucial in future engineering fiber filters towards efficiently removing heavy metal ions using dopamine-modified polypropylene fibers.

  5. Responses of Niphargus montellianus and Gammarus balcanicus (Crustacea, Amphipoda) from karst waters to heavy metal exposure

    Science.gov (United States)

    Coppellotti Krupa, O.; Guidolin, L.

    2003-05-01

    The response to some heavy metals (Cd, Cu, and Zn) was examined in two amphipods, Niphargus montellianus and Gammarus balcanicus, living in karst waters and endowed with different ecological characteristics. Exposure experiments were made, in the controlled conditions of a biospeleology laboratory, to increasing concentrations of metals in the range 0.1 10 μg ml^{-1} for up to 10 days. Hypogean and epigean amphipods differed in their responses, G. balcanicus being more sensitive to the toxic effects of heavy metals than the hypogean N montellianus. The degree of tolerance was Cuheavy metal pollution.

  6. Field accumulation risks of heavy metals in soil and vegetable crop irrigated with sewage water in western region of Saudi Arabia.

    Science.gov (United States)

    Balkhair, Khaled S; Ashraf, Muhammad Aqeel

    2016-01-01

    Wastewater irrigated fields can cause potential contamination with heavy metals to soil and groundwater, thus pose a threat to human beings . The current study was designed to investigate the potential human health risks associated with the consumption of okra vegetable crop contaminated with toxic heavy metals. The crop was grown on a soil irrigated with treated wastewater in the western region of Saudi Arabia during 2010 and 2011. The monitored heavy metals included Cd, Cr, Cu, Pb and Zn for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of sewage irrigation in the future. The pollution load index (PLI), enrichment factor (EF) and contamination factor (CF) of these metals were calculated. The pollution load index of the studied soils indicated their level of metal contamination. The concentrations of Ni, Pb, Cd and Cr in the edible portions were above the safe limit in 90%, 28%, 83% and 63% of the samples, respectively. The heavy metals in the edible portions were as follows: Cr > Zn > Ni > Cd > Mn > Pb > Cu > Fe. The Health Risk Index (HRI) was >1 indicating a potential health risk. The EF values designated an enhanced bio-contamination compared to other reports from Saudi Arabia and other countries around the world. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the indirect utilization of vegetables grown on heavy metal-contaminated soil that was irrigated by contaminated water sources. The okra tested was not safe for human use, especially for direct consumption by human beings. The irrigation source was identified as the source of the soil pollution in this study.

  7. Field accumulation risks of heavy metals in soil and vegetable crop irrigated with sewage water in western region of Saudi Arabia

    Science.gov (United States)

    Balkhair, Khaled S.; Ashraf, Muhammad Aqeel

    2015-01-01

    Wastewater irrigated fields can cause potential contamination with heavy metals to soil and groundwater, thus pose a threat to human beings . The current study was designed to investigate the potential human health risks associated with the consumption of okra vegetable crop contaminated with toxic heavy metals. The crop was grown on a soil irrigated with treated wastewater in the western region of Saudi Arabia during 2010 and 2011. The monitored heavy metals included Cd, Cr, Cu, Pb and Zn for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of sewage irrigation in the future. The pollution load index (PLI), enrichment factor (EF) and contamination factor (CF) of these metals were calculated. The pollution load index of the studied soils indicated their level of metal contamination. The concentrations of Ni, Pb, Cd and Cr in the edible portions were above the safe limit in 90%, 28%, 83% and 63% of the samples, respectively. The heavy metals in the edible portions were as follows: Cr > Zn > Ni > Cd > Mn > Pb > Cu > Fe. The Health Risk Index (HRI) was >1 indicating a potential health risk. The EF values designated an enhanced bio-contamination compared to other reports from Saudi Arabia and other countries around the world. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the indirect utilization of vegetables grown on heavy metal-contaminated soil that was irrigated by contaminated water sources. The okra tested was not safe for human use, especially for direct consumption by human beings. The irrigation source was identified as the source of the soil pollution in this study. PMID:26858563

  8. Concentrations of some heavy metals in underground water samples from a Nigerian crude oil producing community.

    Science.gov (United States)

    Ejike, Chukwunonso E C C; Eferibe, Chinedu O; Okonkwo, Francis O

    2017-03-01

    Pollution due to oil exploration activities in the Niger Delta region of Nigeria and government under-investments in potable water infrastructure has led to the dependence of the population on personal boreholes. Yet, there are little quality or surveillance reports on such waters. The concentrations of heavy metals in underground water samples from an oil producing area, Umuebulu, in the Niger Delta were therefore investigated. Water samples were collected from three test points, each approximately 300 m from (1) wellhead area (WHA), (2) flare area (FA) and (3) effluent discharge area (EDA), and one control point located 10 km away from any oil-related activity. The concentrations of lead, arsenic and cadmium were determined in the samples using atomic absorption spectrophotometry. All three heavy metals were present in the test, and control water samples at concentrations significantly (P water samples showed that their consumption constituted significant health risks in the order EDA > FA > WHA > Control. Appropriate water treatment and surveillance is warranted and therefore recommended for underground water resources of the studied community.

  9. Bathing in carbon dioxide-enriched water alters protein expression in keratinocytes of skin tissue in rats.

    Science.gov (United States)

    Kälsch, Julia; Pott, Leona L; Takeda, Atsushi; Kumamoto, Hideo; Möllmann, Dorothe; Canbay, Ali; Sitek, Barbara; Baba, Hideo A

    2017-04-01

    Beneficial effects of balneotherapy using naturally occurring carbonated water (CO2 enriched) have been known since the Middle Ages. Although this therapy is clinically applied for peripheral artery disease and skin disorder, the underlying mechanisms are not fully elucidated.Under controlled conditions, rats were bathed in either CO2-enriched water (CO2 content 1200 mg/L) or tap water, both at 37 °C, for 10 min daily over 4 weeks. Proliferation activity was assessed by Ki67 immunohistochemistry of the epidermis of the abdomen. The capillary density was assessed by immunodetection of isolectin-positive cells. Using cryo-fixed abdominal skin epidermis, follicle cells and stroma tissue containing capillaries were separately isolated by means of laser microdissection and subjected to proteomic analysis using label-free technique. Differentially expressed proteins were validated by immunohistochemistry.Proliferation activity of keratinocytes was not significantly different in the epidermis after bathing in CO2-enriched water, and also, capillary density did not change. Proteomic analysis revealed up to 36 significantly regulated proteins in the analyzed tissue. Based on the best expression profiles, ten proteins were selected for immunohistochemical validation. Only one protein, far upstream element binding protein 2 (FUBP2), was similarly downregulated in the epidermis after bathing in CO2-enriched water with both techniques. Low FUBP2 expression was associated with low c-Myc immune-expression in keratinocytes.Long-term bathing in CO2-enriched water showed a cellular protein response of epithelial cells in the epidermis which was detectable by two different methods. However, differences in proliferation activity or capillary density were not detected in the normal skin.

  10. Rapid analysis of organic microcontaminants in environmental water samples by trace enrichment and liquid chromatography on a single short column.

    NARCIS (Netherlands)

    Hogenboom, A.C.; Malmqvist, U.K.; Nolkrantz, K.; Vreuls, J.J.; Brinkman, U.A.T.

    1997-01-01

    On-column trace enrichment and liquid chromatography using a single short (20 mm length) high-pressure packed column was optimized for the rapid simultaneous identification and quantification of a wide range of organic microcontaminants in environmental water samples. The quality of different C,,

  11. Spatial assessment and source identification of heavy metals pollution in surface water using several chemometric techniques.

    Science.gov (United States)

    Ismail, Azimah; Toriman, Mohd Ekhwan; Juahir, Hafizan; Zain, Sharifuddin Md; Habir, Nur Liyana Abdul; Retnam, Ananthy; Kamaruddin, Mohd Khairul Amri; Umar, Roslan; Azid, Azman

    2016-05-15

    This study presents the determination of the spatial variation and source identification of heavy metal pollution in surface water along the Straits of Malacca using several chemometric techniques. Clustering and discrimination of heavy metal compounds in surface water into two groups (northern and southern regions) are observed according to level of concentrations via the application of chemometric techniques. Principal component analysis (PCA) demonstrates that Cu and Cr dominate the source apportionment in northern region with a total variance of 57.62% and is identified with mining and shipping activities. These are the major contamination contributors in the Straits. Land-based pollution originating from vehicular emission with a total variance of 59.43% is attributed to the high level of Pb concentration in the southern region. The results revealed that one state representing each cluster (northern and southern regions) is significant as the main location for investigating heavy metal concentration in the Straits of Malacca which would save monitoring cost and time. The monitoring of spatial variation and source of heavy metals pollution at the northern and southern regions of the Straits of Malacca, Malaysia, using chemometric analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Graphene-based sensors for detection of heavy metals in water: a review.

    Science.gov (United States)

    Chang, Jingbo; Zhou, Guihua; Christensen, Erik R; Heideman, Robert; Chen, Junhong

    2014-06-01

    Graphene (G) is attracting significant attention because of its unique physical and electronic properties. The production of graphene through the reduction of graphene oxide (GO) is a low-cost method. The reduction of GO can further lead to electrically conductive reduced GO. These graphene-based nanomaterials are attractive for high-performance water sensors due to their unique properties, such as high specific surface areas, high electron mobilities, and exceptionally low electronic noise. Because of potential risks to the environment and human health arising from heavy-metal pollution in water, G-/GO-based water sensors are being developed for rapid and sensitive detection of heavy-metal ions. In this review, a general introduction to graphene and GO properties, as well as their syntheses, is provided. Recent advances in optical, electrochemical, and electrical detection of heavy-metal ions using graphene or GO are then highlighted. Finally, challenges facing G/GO-based water sensor development and outlook for future research are discussed.

  13. Heavy metals in water and in tissues of himri (Carasobarbus luteus) from Orontes (Asi) River, Turkey.

    Science.gov (United States)

    Yilmaz, Ayşe Bahar; Doğan, Mustafa

    2008-09-01

    Concentrations of heavy metals (Ag, Cd, Cr, Cu, Fe, Ni, Pb ve Zn) were measured in running water and in tissues (muscle, liver, gill, skin and gonads) of one commercially valuable fish species (Carasobarbus luteus) from the Orontes (Asi) River (Güzelburç region) in Hatay (Southeastern Turkey). Results for levels in water compared with national and international water quality guidelines were found at the highest concentrations in international criteria's WHO, EC and EPA, but Cd, Cu, Ni and Pb were found to exceed permissible level of drinking water in national criteria TSE-266 whereas Fe, Zn and Cr concentrations were within the permissible levels for drinking. The present study showed a significant seasonal variation (p 0.05), which showed seasonal variation of only Zn (p < 0.05). Maximum concentrations of Ag, Cd, Cr and Pb were detected in gonads followed by liver, gill, skin and muscle while maximum concentrations of Cu, Fe, Ni and Zn were detected in liver followed by other tissues. Concentrations of heavy metals in the muscle of C. luteus were below the permissible limit for human consumption, level of Cu being very close to the permissible limit. Consequently, continuous monitoring of heavy metal concentration in edible freshwater fish will be needed in Orontes River.

  14. [Identification of partially deuterated exometabolites during culture of tea fungi in heavy water].

    Science.gov (United States)

    Kutyshenko, V P; Iurkevich, D I

    2000-01-01

    Exometabolites of tea fungus during the cultivation on heavy water were studied by methods of high-resolution proton and deuterium exchange. Is was shown that, depending on the degree of exchange of proton for deuterium in the methyl group of acetate, three isotopomers exist: -CH3, -CH2D, and -CHD2. Ethanol is represented by six isotopomers: -CHD-CH3, -CD2-CH3, -CD2-CH2D, -CD2-CHD2, -CHD-CH2D, and -CHD-CHD2. Relative concentration of these isotopomers and the percent content of deuterium were determined. Based on these data, the kinetics of metabolism of the object cultivated on heavy water was analyzed. It was show that the efficiency of glucose utilization is the same as during cultivation on light water with the exception that the time of utilization is significantly greater. At the same time, the parameters of utilization of ethanol and its conversion into acetic acid in the life activity of the tea fungus in heavy and light water are very similar.

  15. Novel biopolymer-coated hydroxyapatite foams for removing heavy-metals from polluted water

    Energy Technology Data Exchange (ETDEWEB)

    Vila, M.; Sanchez-Salcedo, S.; Cicuendez, M.; Izquierdo-Barba, I. [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain); Vallet-Regi, Maria, E-mail: vallet@farm.ucm.es [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain)

    2011-08-15

    Highlights: {yields} 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams as potential devices for the treatment of heavy metal ions. {yields} HA stable foams coated with biopolymers. {yields} Feasible advance in development of new, easy to handle and low cost water purifying methods. - Abstract: 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams have been developed as potential devices for the treatment of lead, cadmium and copper contamination of consumable waters. These foams have exhibited a fast and effective ion metal immobilization into the HA structure after an in vitro treatment mimicking a serious water contamination case. To improve HA foam stability at contaminated aqueous solutions pH, as well as its handling and shape integrity the 3D-macroporous foams have been coated with biopolymers polycaprolactone (PCL) and gelatine cross-linked with glutaraldehyde (G/Glu). Metal ion immobilization tests have shown higher and fast heavy metals captured as function of hydrophilicity rate of biopolymer used. After an in vitro treatment, foam morphology integrity is guaranteed and the uptake of heavy metal ions rises up to 405 {mu}mol/g in the case of Pb{sup 2+}, 378 {mu}mol/g of Cu{sup 2+} and 316 {mu}mol/g of Cd{sup 2+}. These novel materials promise a feasible advance in development of new, easy to handle and low cost water purifying methods.

  16. Effect of administration of water enriched in O2 by injection or electrolysis on transcutaneous oxygen pressure in anesthetized pigs

    Directory of Open Access Journals (Sweden)

    Charton A

    2014-08-01

    Full Text Available Antoine Charton,1 François Péronnet,2 Stephane Doutreleau,3 Evelyne Lonsdorfer,3 Alexis Klein,4 Liliana Jimenez,4 Bernard Geny,3 Pierre Diemunsch,1 Ruddy Richard5 1Department of Anesthesia and Critical Care, and EA 3072, Hôpital de Hautepierre; University of Strasbourg, Strasbourg, France; 2Department of Kinesiology, Université de Montréal, Montreal, QC, Canada; 3CHRU of Strasbourg, Physiology and Functional Explorations Department, New Civil Hospital, Strasbourg, France and University of Strasbourg, Faculty of Medicine, Physiology Department, Strasbourg, France; 4Danone Research, Palaiseau, France; 5Department of Sport Medicine and Functional Explorations, CHU Clermont-Ferrand and INRA UMR 1019, CRNH-Auvergne, Clermont-Ferrand, France Background: Oral administration of oxygenated water has been shown to improve blood oxygenation and could be an alternate way for oxygen (O2 supply. In this experiment, tissue oxygenation was compared in anesthetized pigs receiving a placebo or water enriched in O2 by injection or a new electrolytic process. Methods: Forty-two pigs randomized in three groups received either mineral water as placebo or water enriched in O2 by injection or the electrolytic process (10 mL/kg in the stomach. Hemodynamic parameters, partial pressure of oxygen in the arterial blood (PaO2, skin blood flow, and tissue oxygenation (transcutaneous oxygen pressure, or TcPO2 were monitored during 90 minutes of general anesthesia. Absorption and tissue distribution of the three waters administered were assessed using dilution of deuterium oxide. Results: Mean arterial pressure, heart rate, PaO2, arteriovenous oxygen difference, and water absorption from the gut were not significantly different among the three groups. The deuterium to protium ratio was also similar in the plasma, skin, and muscle at the end of the protocol. Skin blood flow decreased in the three groups. TcPO2 slowly decreased over the last 60 minutes of the experiment in

  17. Light emission of sputtered particles induced by ion bombardment on water-enriched molecular ices

    Science.gov (United States)

    Lee, Chin Shuang; Ip, Wing; Liu, S. H.; Hsu, G. Y.; Lee, Shyong

    2007-03-01

    We had measured the light of sputtered particles in a visible region induced by various projectiles bombarding water-enriched molecular ices, like mixed ices of CH4 + NH3 + H2O (1:1:1). In this experiment, each constituent contained in this iced sample was found to emit a characteristic wavelength of light. We believe this characteristic is due to certain ion attached to parent molecule (constituent) that are dissociated with parent molecule in the collision process. Some of those ions, before emerging out the iced film, will become neutralized and develop into excited states due to electron capture. Then the characteristic wavelengths of light will decay from these excited sputtered particles; hence, from the light emission, one can analyze the constituents of an unknown ice. On the other hand, the intensity of the distribution of light emission during ion bombardment can be interpreted as an ion-ice interaction following the similar collision mechanism as ion-metal interaction, i.e. mainly the linear-cascade collision model.

  18. Heavy metals in a latin american coastal lagoon - sediments, water and macrophytes

    OpenAIRE

    Ambrozic, Nada

    2015-01-01

    Dissertação de mestrado, Ecohidrologia, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015 Coastal lagoons are considered to be some of the most productive ecosystems on Earth, providing a wide range of ecosystem services and resources. Jacunem lagoon, ES, Brazil, was studied to evaluate the impact of anthropogenic activities on heavy metal concentrations in sediments, water and macrophytes (Eichhornia crassipes and Typha domingensis). In order to verify the presence of heav...

  19. Pelletized ponderosa pine bark for adsorption of toxic heavy metals from water

    Science.gov (United States)

    Miyoung Oh; Mandla A. Tshabalala

    2007-01-01

    Bark flour from ponderosa pine (Pinus ponderosa) was consolidated into pellets using citric acid as cross-linking agent. The pellets were evaluated for removal of toxic heavy metals from synthetic aqueous solutions. When soaked in water, pellets did not leach tannins, and they showed high adsorption capacity for Cu(ll), Zn(ll), Cd(ll). and Ni(ll) under both equilibrium...

  20. THE THEORETICAL CRITERIA ON THE VAPORIZATION AND COMBUSTION RATES OF EMULSIONS WATER IN HEAVY FUEL OIL

    Directory of Open Access Journals (Sweden)

    Corneliu MOROIANU

    2012-05-01

    Full Text Available The vaporization and combustion characteristics of a heavy oil-water emulsion droplet are investigated with graphological method. The combustion graphology of fuel oils is defined as a new technical and scientific field which deals with the graphic transposition of the processes of fuels combustion development in a simulator. Thus, it is easy to establish the ignition-combustion characteristics, including the laws that govern their changes depending on the combustion conditions and fuel specifications

  1. HEAVY METALS IN WATERS, PENETRATING THE FOOD, ECOSYSTEMS AND THE ECONOMY OF KOSOVO

    OpenAIRE

    Adem Dreshaj; Bedri Millaku; Afrim Selimaj; Fidan Feka; Muhamet Kelmendi

    2016-01-01

    The waters of the oceans and seas play an important role in the hydrological cycle of the Earth. With Kosovo's economic development, increasing population developed many branches of industry, which caused pollution of rivers with heavy metals such as mine "Trepça", the treatment of agriculture products with pesticides and herbicides, eutrophication of lakes, transition metal in agricultural products, coming up ecological balance disorders. Uncontrolled exploitation of natural resources, irres...

  2. Heavy metal content of alfalfa irrigated with waste and tubewell water

    OpenAIRE

    Mohammad Jamal Khan; Mohammad Tariq Jan; Dost Mohammad

    2011-01-01

    A field experiment was conducted to study the effect of wastewater on yield and heavy metal uptake of alfalfa along with a tubewell irrigated crop as control at the Agricultural University Peshawar during 2009. The experiment was conducted in small plots (2 x 1m) replicated thrice with fertilizer additions. The crop was either irrigated with Hayatabad Industrial Estate (HIE) wastewater or tubewell water. The yield data revealed that shoot dry weight was significantly affected by the irrigatio...

  3. Analysis of isotope element by electrolytic enrichment method for ground water and surface water in Saurashtra region, Gujarat, India

    Directory of Open Access Journals (Sweden)

    Sajal Singh

    2016-12-01

    Full Text Available The present study has been aimed for the assessment of isotope element Tritium (3H. It is a great threat to human health and environment for lengthy duration. The tritium exists in earth in diverse forms such as (1 small amounts of natural tritium are produced by alpha decay of lithium-7, (2 natural atmospheric tritium is also generated by secondary neutron cosmic ray bombardment of nitrogen, (3 atmospheric nuclear bomb testing in the 1950s, although the contribution from nuclear power plants is small. Tritium or 3H is a radioactive isotope of hydrogen with a half-life of 12.32 ± 0.02 years. Water samples from ground water, surface water, and precipitation were collected from different locations in Gujarat area and were analyzed for the same. Distillation of samples was done to reduce the conductivity. Deuterium and Hydrogen were removed by the process of physico-chemical fractionation in the tritium enrichment unit. The basis of physico-chemical fractionation is the difference in the strength of bonds formed by the light vs. the heavier isotope of a given element. A total of 10 cycles (runs were executed using Quintals process. Tritium concentration files were created with help of WinQ and Quick start software in Quintals process (Liquid Scintillation Spectrometer. The concentration of tritium in terms of tritium units (TU of various samples has been determined. The TU values of the samples vary in the range of 0.90–6.62 TU.

  4. Assay of low deuterium enrichment of water by isotopic exchange with [U-13C3]acetone and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Yang, D; Diraison, F; Beylot, M; Brunengraber, D Z; Samols, M A; Anderson, V E; Brunengraber, H

    1998-05-01

    A sensitive assay of the 2H-enrichment of water based on the isotopic exchange between the hydrogens of water and of acetone in alkaline medium is described and validated. For low 2H-enrichments (0.008 to 0.5%), the sample is spiked with [U-13C3]acetone and NaOH. After exchange, 2H-enriched [U-13C3]acetone is extracted with chloroform and assayed by gas chromatography-mass spectrometry. With some instruments, ion-molecule reactions, resulting in increased baseline enrichment, are minimized by lowering the electron ionization energy from the usual 70 to 10 eV. The 2H-enrichment of water is amplified nearly sixfold in the M4/M3 ratio of [U-13C3]acetone. For high 2H-enrichments (0.25 to 100%), the use of unlabeled acetone suffices. After exchange, the mass isotopomer distribution of acetone is analyzed, yielding the 2H-enrichment of water. The assay with [U-13C3]acetone allows measuring the 2H-enrichment of water even in biological samples containing acetone. This technique is more rapid and economical than the classical isotope ratio mass spectrometric assay of the enrichment of hydrogen gas derived from the reduction of water.

  5. Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey

    Directory of Open Access Journals (Sweden)

    Mehmet Emin Aydin

    2013-01-01

    Full Text Available The concentrations of organochlorine pesticides (OCPs, including α-, β-, γ-, and δ-hexachlorocyclohexane (HCH, heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p′-DDE, p,p′-DDD, p,p′-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, β-HCH is the main isomer with a concentration range of 0.015–0.065 μg/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 μg/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 μg/L. The concentrations of heavy metals in water samples were observed with order: Mn < Cu < Ni < As < Cr < Fe. In some samples, As, Fe, and Cr concentrations exceeded the drinking water quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data.

  6. Production of a New Emulsifier Material for the Formation Heavy Hydrocarbon/Water Emulsion

    Directory of Open Access Journals (Sweden)

    Afshin Farahbakhsh

    2011-04-01

    Full Text Available Emulsifiers are a unique class of compounds that have proved to have a variety of potential applications in formation of hydrocarbon in water emulsion, in enhancement of oil recovery and in the reduction of heavy oil viscosity. In this paper, a bio emulsifier was synthesized by a strain of Bacillus licheniformis and was separated by an autoclave and centrifugal process; the purification of bio emulsifier and the increase quality of product was done by adding sulfuric acid (H2SO4 (98% to the solution and centrifuging this compound again. This bio emulsifier has the property of emulsification to a wide range of heavy hydrocarbon to form a stable hydrocarbon-water emulsion. This bio emulsifier could reduce Iranian Nuroze high viscosity oil of about 10000 cP down to 250 cP. This means about 97% decreases in the viscosity. The emulsion stable this condition for 48 hr and the viscosity slowly increases to 4000cp until 192 hr. The stability of the oil in water emulsion during 48hr allows the heavy oil to be transported practically over lengthy distances or remain stable for long periods of time prior to utilization.

  7. A study of the tritium behavior in coolant and moderator system of heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. P.; Song, S. S.; Chae, K. S. and others [Chosun Univ., Gwangju (Korea, Republic of)

    1993-12-15

    The objectives of this report is to present a regulatory policy on the environmental impact and personnel exposure by understanding the generation, accumulation, environmental release and management of tritium in heavy water reactors. By estimating the tritium concentration at Wolsong nuclear plant site by estimating and forecasting the generation and accumulation of tritium in coolant and moderator systems at Wolsong unit 1, we will study the management and release of tritium at Wolsong units 3 and 4 which are ready for construction. The major activities of this study are as follows : tritium generation and accumulation in heavy water reactor, a quantitative assessment of the accumulation and release of tritium at Wolsong nuclear plant site, heavy water management at Wolsong nuclear plants. The tritium concentration and accumulation trends in the systems at Wolsong unit 1 was estimated. A quantitative assessment of the tritium accumulation and release for Wolsong 2, 3 and 4 based on data from Wolsong 1 was performed. The tritium removal schemes and its long-term management plan were made.

  8. Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

    Directory of Open Access Journals (Sweden)

    Mustapha Moshood Keke

    2016-06-01

    Full Text Available Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could become a health hazard. The dry season concentrations of cadmium, copper, iron, lead, mercury, nickel and zinc were assessed from three sites for 12 weeks in Oyun reservoir, Offa, Nigeria. Triplicate surface water samples were collected and analysed using atomic absorption spectrophotometry. The trend in the level of concentrations in the three sites is site C > B > A, while the trend in the levels of the concentrations in the reservoir is Ni > Fe > Zn > Pb > Cd > Cu > Hg. Ni, Cd, Pb and Hg were found to be higher than the WHO guidelines for the metals in drinking water. The high concentration of these metals was from anthropogenic watershed run-off of industrial effluents, domestic sewages and agricultural materials into the reservoir coming from several human activities such as washing, bathing, fish smoking, especially in site C. The health effects of high concentration of these metals in the reservoir were highlighted. Methods for the treatment and removal of the heavy metals from the reservoir during water purification such as active carbon adsorption, coagulation-flocculation, oxidation-filtration, softening treatment and reverse osmosis process were highlighted. Other methods that could be used include phytoremediation, rhizofiltration, bisorption and bioremediation. Watershed best management practices (BMP remains the best solution to reduce the intrusion of the heavy metals from the watershed into the reservoir.

  9. Alkaline peptone water enrichment with a dipstick test to quickly detect and monitor cholera outbreaks

    Directory of Open Access Journals (Sweden)

    Godfrey Bwire

    2017-11-01

    Full Text Available Abstract Background Detection, confirmation and monitoring of cholera outbreaks in many developing countries including Uganda is a big challenge due to lack of the required resources and the time the test takes. Culture method which takes 24–48 h to get the feedback and requires highly skilled laboratory staff plus other complex resources is the standard test. This study evaluated the new cholera rapid detection method that relies on Crystal VC dipsticks after enrichment with alkaline peptone water (APW against the culture method for monitoring the progress of cholera outbreaks in rural setting. Methods We conducted the study between March and June 2015. Fresh stool samples and rectal swabs were incubated in 1% APW for 6 h at room temperature before testing with RDT following the manufacturer’s instruction. The same stool sample was cultured to isolate V. cholerae in the standard manner. We also reviewed patient registers to epidemiologically describe the cholera epidemic. Results We tested stool from 102 consenting suspected cholera patients reporting during daytime at Bwera Hospital (n = 69, Kilembe Mines Hospital (n = 4 and Kinyabwama Health Centre (n = 29. Ninety one (91 samples were positive and nine samples were negative according to both methods. One (1 sample was positive only by dipstick and one sample was positive only by culture (sensitivity of 99%, specificity of 90%, Positive Predictive Value of 99% and Negative Predictive Value of 90%. Overall, 146 suspected cholera cases and two deaths, (case fatality rate of 1.36% were recorded during the study period. Among the cases aged 1–9 years, 63% (50/79 were males while in those aged 20–49 years, 76% (34/45 were females. Conclusions Our findings showed that the modified dipstick test after enrichment with 1% APW had high level of accuracy in detection of V. cholerae and is quick, affordable alternative cholera outbreak monitoring tool in resource constrained

  10. [A novel vapor dynamic headspace enrichment equipment for nontarget screening of volatile organic compounds in drinking water].

    Science.gov (United States)

    Ma, Huilian; Zhang, Haijun; Tian, Yuzeng; Wang, Longxing; Chen, Jiping

    2011-09-01

    A novel vapor dynamic headspace enrichment device was set up for nontarget screening of volatile organic compounds (VOCs) in drinking water. The main operating parameters of this device, such as length of distillation tube, volume of collected condensate, and choice of absorbent, were optimized. In this device, vapor was utilized as a purge gas and water was utilized as a absorbent. With the help of the device, one liter of water sample could be concentrated to 5 mL and the sensitivity of traditional purge and trap-gas chromatography-mass spectrometry (P&T-GC-MS) could be improved 1-2 orders of magnitude. Source and disinfected water samples from a water treatment plant were analyzed with this method. Compared with the traditional P&T-GC-MS analysis without pre-enrichment, the numbers of identified VOCs were improved from 0 to 16 for source water and 5 to 35 for disinfected water samples. It is also shown that there are many halide compounds in VOCs in disinfected water which do not exist in source water.

  11. Irrigation water quality influences heavy metal uptake by willows in biosolids.

    Science.gov (United States)

    Laidlaw, W Scott; Baker, Alan J M; Gregory, David; Arndt, Stefan K

    2015-05-15

    Phytoextraction is an effective method to remediate heavy metal contaminated landscapes but is often applied for single metal contaminants. Plants used for phytoextraction may not always be able to grow in drier environments without irrigation. This study investigated if willows (Salix x reichardtii A. Kerner) can be used for phytoextraction of multiple metals in biosolids, an end-product of the wastewater treatment process, and if irrigation with reclaimed and freshwater influences the extraction process. A plantation of willows was established directly onto a tilled stockpile of metal-contaminated biosolids and irrigated with slightly saline reclaimed water (EC ∼2 dS/cm) at a wastewater processing plant in Victoria, Australia. Biomass was harvested annually and analysed for heavy metal content. Phytoextraction of cadmium, copper, nickel and zinc was benchmarked against freshwater irrigated willows. The minimum irrigation rate of 700 mm per growing season was sufficient for willows to grow and extract metals. Increasing irrigation rates produced no differences in total biomass and also no differences in the extraction of heavy metals. The reclaimed water reduced both the salinity and the acidity of the biosolids significantly within the first 12 months after irrigation commenced and after three seasons the salinity of the biosolids had dropped to metal extraction. Reclaimed water irrigation reduced the biosolid pH and this was associated with reductions of the extraction of Ni and Zn, it did not influence the extraction of Cu and enhanced the phytoextraction of Cd, which was probably related to the high chloride content of the reclaimed water. Our results demonstrate that flood-irrigation with reclaimed water was a successful treatment to grow willows in a dry climate. However, the reclaimed water can also change biosolids properties, which will influence the effectiveness of willows to extract different metals. Copyright © 2015 Elsevier Ltd. All rights

  12. Separation of heavy metal from water samples--The study of the synthesis of complex compounds of heavy metal with dithiocarbamates.

    Science.gov (United States)

    Kane, Sonila; Lazo, Pranvera; Ylli, Fatos; Stafilov, Trajce; Qarri, Flora; Marku, Elda

    2016-01-01

    The toxicity and persistence of heavy metal (HM) ions may cause several problems to marine organisms and human beings. For this reason, it is growing the interest in the chemistry of sulphur donor ligands such as dithiocarbamates (DDTC), due to their applications particularly in analytical chemistry sciences. The aim of this work has been the study of heavy metal complexes with DDTC and their application in separation techniques for the preconcentration and/or removing of heavy metals from the water solutions or the water ecosystems prior to their analysis. The HM-DDTC complexes were prepared and characterized by elemental analysis, FTIR and UV-Vis spectroscopic methods. The elemental analysis and the yield of the synthesis (97.5-99.9%) revealed a good purity of the complexes. High values of complex formation yields of HM-DDTC complexes is an important parameter for quantitatively removing/and or preconcentration of heavy metal ions from water solution even at low concentration of heavy metals. Significant differences founded between the characteristic parameters of UV/Vis (λmax and ϵmax) and FTIR absorption spectra of the parent DDTC and HM-DDTC complexes revealed the complex formation. The presence of the peaks at the visible spectral zone is important to M(nd(10-m))-L electron charge transfer of the new complexes. The (C=N) (1450-1500 cm(-1)) and the un-splitting (C-S) band (950-1002 cm(-1)) in HM-DDTC FTIR spectra are important to the identification of their bidentate mode (HM[S2CNC4H10]2). The total CHCl3 extraction of trace level heavy metals from water samples after their complex formation with DDTC is reported in this article.

  13. Three-phase pressure drop in heavy oil, water and gas flow in a horizontal pipe for application in heavy oil transportation

    Energy Technology Data Exchange (ETDEWEB)

    Trevisan, Francisco E.; Bannwart, Antonio Carlos [Universidade Estadual de Campinas, SP (Brazil)

    2003-07-01

    A significant extent of the Brazilian oil reserves consists of heavy oil, and its importance and economic value have been increasing in the last years. However, these oils, besides their elevated densities (API degree lower than 20), have viscosities higher than 100 mPa.s , which makes it more difficult to transport them through pipelines. A solution for this problem is the injection of water in the pipe, in such a way to reduce friction and, consequently, the energy expend for a given oil flow rate. The two-phase flow of heavy oil and water has been the object of a number of recent studies, and concepts such as the core-flow technology can be useful for heavy oil transportation. But in production operations, gas is also present, initially dissolved in the oil phase then leaving the solution to form a free gas phase if the pressure is below the bubble point pressure. Thus the study of three-phase flow of heavy oil, water and gas is in order. The present paper presents the three-phase flow pressure drop measured in a horizontal glass tube of 2.84 cm i.d. at several combinations of the individual flow rates. Initially, for the development of the experiment, two-phase flow of heavy oil-water and gas-water were studied to establish the flow rate ranges that cover the main patterns already known. The superficial velocities used varied from 0.04 to 0.5 m/s for water, 0.04 to 9.0 m/s for gas and 0.02 to 1.2 m/s for oil. For each test run, the three-phase flow pressure drop was determined with the help of absolute and differential pressure transducers. The results are shown in the form of maps in terms of superficial velocities. (author)

  14. Heavy metals in the waste and in the water discharge area of municipal solid waste

    Directory of Open Access Journals (Sweden)

    Luiz Ermindo Cavallet

    2013-12-01

    Full Text Available The county of Paranaguá discards 80 tons of municipal solid waste (MSW daily in the Embocuí landfill without proper treatment. The present study aimed to evaluate the concentration of arsenic (As, cadmium (Cd, chromium (Cr, lead (Pb and mercury (Hg in the dump area and to compare it with reference values for soil and water quality stipulated by CETESB (2005. The methodology of the study involved the collection of waste samples (organic waste mixed with soil from a depth of 1 m deep at 12 points of the dump, and the collection of water samples from a depth of 3 m at 3 points in the deposited waste. Extraction of heavy metals in the water samples was performed according to the USEPA (1999 method and analysis followed ICP-OES (Inductively Coupled Plasma - Atomic Emission Spectrometry. Analysis of the solid waste samples showed the following concentrations: (mg kg -1: As < 10; Cd < 1; Cr = 26; Pb = 52; e Hg = 0.2. The water samples showed the following concentrations: (mg L- 1: As < 5; Cd < 5; Cr =29 e Pb = 10. The amounts of heavy metals in samples of tailings and water from the landfill area fall below the values considered to create a risk of contamination.

  15. Sustainable sources of biomass for bioremediation of heavy metals in waste water derived from coal-fired power generation

    National Research Council Canada - National Science Library

    Saunders, Richard J; Paul, Nicholas A; Hu, Yi; de Nys, Rocky

    2012-01-01

    .... We cultured three species of algae with and without nutrient addition in water that was contaminated with heavy metals from an Ash Dam associated with coal-fired power generation and tested metal...

  16. The influence of chemical protection on the content of heavy metals in wheat (Triticum aestivum L.) growing on the soil enriched with granular sludge.

    Science.gov (United States)

    Wołejko, E; Łozowicka, B; Kaczyński, P; Konecki, R; Grobela, M

    2017-08-01

    The presence of heavy metals in Triticum aestivum L. growing on the soil enriched with granular sludge after chemical protection was observed. The five variants of treatments using herbicide (Chwastox Turbo 340SL) and four fungicides (Topsin M 500SC, Amistar 250SC, Artea 330EC, and Falcon 460EC) were performed. On control and experimental plots, the concentration of Ni, Pb, Cr, and Cu in wheat leaves were in the range 0.32-0.99, 0.92-1.57, 0.89-6.31, and 7.08-12.59 mg/kg and in grains 0.03 to 0.11, 0.14-0.25, 0.11-0.76, and 1.06-1.46 mg/kg, respectively. The concentration of Pb in grain protected by MCPA and 2,4-D with thiophanate-methyl and azoxystrobin was higher than the maximum levels of 0.20 mg/kg D.M. The bioconcentration factor (BCF) differed and depended on chemical protection. The highest value of BCF was achieved for Cd. The statistical analysis showed a significant correlation between concentration of metals and quality parameters of wheat. One observed significant negative correlations between Ni/Zeleny sedimentation value (r = -0.51) and between Pb/starch content (r = -0.57). Positive correlations were observed between Cd/yield, the number of grains/ergosterol concentration (respectively, r = 0.41, r = 0.55, r = 0.56), and Zn/thousand grain weight (r = 0.50) at a p ≤ 0.05.

  17. Leaf water enrichment of stable water isotopes (δ18O and δD) in a mature oil palm plantation in Jambi province, Indonesia.

    Science.gov (United States)

    Bonazza, Mattia; Tjoa, Aiyen; Knohl, Alexander

    2017-04-01

    During the last few decades, Indonesia experienced rapid and large scale land-use change towards intensively managed crops, one of them is oil palm. This transition results in warmer and dryer conditions in microclimate. The impacts on the hydrological cycle and on water-use by plants are, however, not yet completely clear. Water stable isotopes are useful tracers of the hydrological processes and can provide means to partition evapotranspiration into evaporation and transpiration. A key parameter, however, is the enrichment of water stable isotope in plant tissue such as leaves that can provide estimates on the isotopic composition of transpiration. Here we present the results of a field campaign conducted in a mature oil palm plantation in Jambi province, Indonesia. We combined continuous measurements of water vapor isotopic composition and mixing ratio with isotopic analysis of water stored in different pools like oil palm leaves, epiphytes, trunk organic matter and soil collected over a three days period. Leaf enrichment varied from -2 ‰ to 10 ‰ relative to source (ground) water. The temporal variability followed Craig and Gordon model predictions for leaf water enrichment. An improved agreement was reached after considering the Péclet effect with an appropriate value of the characteristic length (L). Measured stomatal conductance (gs) on two different sets of leaves (top and bottom canopy) was mainly controlled by radiation (photosynthetically active radiation) and vapor pressure deficit. We assume that this control could be explained in conditions where soil water content is not representing a limiting factor. Understanding leaf water enrichment provides one step towards partitioning ET.

  18. Nutrient Limitation in Surface Waters of the Oligotrophic Eastern Mediterranean Sea: an Enrichment Microcosm Experiment

    KAUST Repository

    Tsiola, A.

    2015-12-01

    The growth rates of planktonic microbes in the pelagic zone of the Eastern Mediterranean Sea are nutrient limited, but the type of limitation is still uncertain. During this study, we investigated the occurrence of N and P limitation among different groups of the prokaryotic and eukaryotic (pico-, nano-, and micro-) plankton using a microcosm experiment during stratified water column conditions in the Cretan Sea (Eastern Mediterranean). Microcosms were enriched with N and P (either solely or simultaneously), and the PO4 turnover time, prokaryotic heterotrophic activity, primary production, and the abundance of the different microbial components were measured. Flow cytometric and molecular fingerprint analyses showed that different heterotrophic prokaryotic groups were limited by different nutrients; total heterotrophic prokaryotic growth was limited by P, but only when both N and P were added, changes in community structure and cell size were detected. Phytoplankton were N and P co-limited, with autotrophic pico-eukaryotes being the exception as they increased even when only P was added after a 2-day time lag. The populations of Synechococcus and Prochlorococcus were highly competitive with each other; Prochlorococcus abundance increased during the first 2 days of P addition but kept increasing only when both N and P were added, whereas Synechococcus exhibited higher pigment content and increased in abundance 3 days after simultaneous N and P additions. Dinoflagellates also showed opportunistic behavior at simultaneous N and P additions, in contrast to diatoms and coccolithophores, which diminished in all incubations. High DNA content viruses, selective grazing, and the exhaustion of N sources probably controlled the populations of diatoms and coccolithophores.

  19. [Surveillance and forecast system of schistosomiasis in Jiangsu Province. VI. Detection technology of water infectivity based on enrichment of Schistosoma japonicum cercariae on water surface].

    Science.gov (United States)

    Qu, Guo-li; Dai, Jian-rong; Xing, Yuan-tian; Wang, Wei; Yang, Zhen-kun; Zhao, Zheng-yang; Guo, Na; Sun, Le-ping; Liang, You-Sheng

    2014-10-01

    To explore the enrichment technique of Schistosoma japonicum cercariae on the water surface, so as to establish a new method combined with the existing technology to detect the cercarial infested water body quickly and sensitively. Soybean oil, gasoline, kerosene and isophorone were screened as expanding agents. The cercariae were enriched by the thrust of the expanding agents when diffusing on the water surface, and PE adsorption film and C-6 film were applied to seize them so as to determine the infectivity of the water quickly. The relationship between the dose of expanding agents and diffusion radius were explored. Gasoline, kerosene and isophorone were suitable expanding agents, and the diffusion effect of isophorone was the best. After the enrichment by the expanding agents, the detection rate of cercariae of the method seizing cercariae with the film significantly improved in the water. This new method could effectively improve the detection rate of the cercarial infested water and is suitable for the low-degree infested water.

  20. Two-dimensional neutron scattering in a floating heavy water bridge

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Elmar C [Wetsus, Centre of Excellence for Sustainable Water Technology, Agora 1, 8900 CC Leeuwarden (Netherlands); Baroni, Patrick; Noirez, Laurence [Laboratoire Leon Brillouin, CEA-CNRS/IRAMIS, CE-Saclay, 91191 Gif-sur-Yvette Cedex (France); Bitschnau, Brigitte [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Rechbauerstrasse 12, 8010 Graz (Austria)

    2010-03-17

    When a high voltage is applied to pure water in two filled beakers kept close to each other, a connection forms spontaneously, giving the impression of a floating water bridge. This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. In this work, the first two-dimensional structural study of a floating heavy water bridge is presented as a function of the azimuthal angle. A small anisotropy in the angular distribution of the intensity of the first structural peak was observed, indicating a preferred orientation of a part of the D{sub 2}O molecules along the electric field lines without breaking the local tetrahedral symmetry. The experiment is carried out by neutron scattering on a D{sub 2}O bridge.

  1. Irrigation water quality in southern Mexico City based on bacterial and heavy metal analyses

    Energy Technology Data Exchange (ETDEWEB)

    Solis, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apdo Postal 20-364, 01000 Mexico, DF (Mexico)]. E-mail: corina@fisica.unam.mx; Sandoval, J. [Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Apdo Postal 70-275, 04510 Mexico, DF (Mexico); Perez-Vega, H. [Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Ave. Universidad S/N. Zona de la Cultura, 86040 Villa Hermosa, Tabasco (Mexico); Mazari-Hiriart, M. [Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Apdo Postal 70-275, 04510 Mexico, DF (Mexico)

    2006-08-15

    Xochimilco is located in southern Mexico City and represents the reminiscence of the pre-Columbian farming system, the 'chinampa' agriculture. 'Chinampas' are island plots surrounded by a canal network. At present the area is densely urbanized and populated, with various contaminant sources contributing to the water quality degradation. The canal system is recharged by a combination of treated-untreated wastewater, and precipitation during the rainy season. Over 40 agricultural species, including vegetables, cereals and flowers, are produced in the 'chinampas'. In order to characterize the quality of Xochimilcos' water used for irrigation, spatial and temporal contaminant indicators such as microorganisms and heavy metals were investigated. Bacterial indicators (fecal coliforms, fecal enterococcus) were analyzed by standard analytical procedures, and heavy metals (such as Fe, Cu, Zn and Pb) were analyzed by particle induced X-ray emission (PIXE). The more contaminated sites coincide with the heavily populated areas. Seasonal variation of contaminants was observed, with the higher bacterial counts and heavy metal concentrations reported during the rainy season.

  2. Heavy metals in a degraded soil treated with sludge from water treatment plant

    Directory of Open Access Journals (Sweden)

    Teixeira Sandra Tereza

    2005-01-01

    Full Text Available The application of water treatment sludge (WTS to degraded soil is an alternative for both residue disposal and degraded soil reclaim. This study evaluated effects of the application of water treatment sludge to a Typic Hapludox soil degraded by tin mining in the National Forest of Jamari, State of Rondonia, Brazil, on the content of heavy metals. A completely randomized experimental design with five treatments was used: control (n = 4; chemical control, which received only liming (n = 4; and rates D100, D150 and D200, which corresponded to 100, 150 and 200 mg of N-sludge kg-1 soil (n = 20, respectively. Thirty days after liming, period in which soil moisture was kept at 70% of the retention capacity, soil samples were taken and analyzed for total and extractable Fe, Cu, Mn, Zn, Cd, Pb, Ni, and Cr. The application of WTS increased heavy-metal contents in the degraded soil. Although heavy metals were below their respective critical limits, sludge application onto degraded areas may cause hazardous environmental impact and thus must be monitored.

  3. STUDIES ON ANTIBIOTICS AND HEAVY METAL RESISTANCE PROFILING OF ESCHERICHIA COLI FROM DRINKING WATER AND CLINICAL SPECIMENS

    OpenAIRE

    R. S. Kawane

    2012-01-01

    Bacterial resistance to antibiotics and heavy metals is an increasing problem in today’s society. Antibiotics resistances in the clinical isolates were high as compare to E.coli from drinking water. The drinking water and clinical E.coli showed more or less equal resistance to antibiotic: metronidazole, penicillin, clindamycin, cephoxithin and heavy metals; copper, mercury and lead, except cadmium metal ions. Multiple antibiotic resistance (MAR) indices in the clinical isolates were high as ...

  4. Heavy metals in water, sediment and tissues of Leuciscus cephalus from a stream in southwestern Turkey.

    Science.gov (United States)

    Demirak, Ahmet; Yilmaz, Fevzi; Tuna, A Levent; Ozdemir, Nedim

    2006-06-01

    Concentrations of heavy metals (Cd, Cr, Cu, Pb and Zn) were measured in water, bottom sediment and tissues (muscle and gills) of Leuciscus cephalus from the Dipsiz stream in the Yatagan basin (southwestern Turkey), the site of a thermal power plant. Results for levels in water were compared with national and international water quality guidelines, as well as literature values were reported for streams and rivers. Comparisons were made of metal concentrations in water and sediment with those in the muscle and gills of L. cephalus caught from the Dipsiz stream. We found that there was metal accumulation in the gills compared to the muscle. Concentrations of Cd, Pb, Zn and Cr in the gills were higher than that in the muscle; however, Cu levels were higher in muscle than that in gills. Concentrations of heavy metals in L. cephalus muscle were below the legal limits for human consumption, although Cr, Pb and Zn levels in the gills were above the limits in the fish taken from the Dipsiz stream. On the other hand, no correlation was found between metal concentrations in water and sediment or between metal concentrations in water and muscle and gills of L. cephalus. A positive correlation was found between concentrations of Cu and Zn in the sediment and in fish tissue, whereas there was no relationship between other metal concentrations in the sediment and water, and muscle and gills of L. cephalus. As with water, Pb and Cd concentrations in particular were higher in sediment than that in background levels. The results show that the pollutants from the thermal power plant may be a source of these elements.

  5. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    Science.gov (United States)

    Pujol, Luca; Evrard, David; Groenen-Serrano, Karine; Freyssinier, Mathilde; Ruffien-Ciszak, Audrey; Gros, Pierre

    2014-04-01

    A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic “on line” monitoring devices are also evoked.

  6. Modeling Adsorption Based Filters (Bio-remediation of Heavy Metal Contaminated Water)

    Science.gov (United States)

    McCarthy, Chris

    I will discuss kinetic models of adsorption, as well as models of filters based on those mechanisms. These mathematical models have been developed in support of our interdisciplinary lab group, which is centered at BMCC/CUNY (City University of New York). Our group conducts research into bio-remediation of heavy metal contaminated water via filtration. The filters are constructed out of biomass, such as spent tea leaves. The spent tea leaves are available in large quantities as a result of the industrial production of tea beverages. The heavy metals bond with the surfaces of the tea leaves (adsorption). The models involve differential equations, stochastic methods, and recursive functions. I will compare the models' predictions to data obtained from computer simulations and experimentally by our lab group. Funding: CUNY Collaborative Incentive Research Grant (Round 12); CUNY Research Scholars Program.

  7. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    Directory of Open Access Journals (Sweden)

    Luca ePUJOL

    2014-04-01

    Full Text Available A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic on line monitoring devices are also evoked.

  8. Separation and recovery of heavy metals from waste water using synergistic solvent extraction

    Science.gov (United States)

    Li, Yan; Yang, Limei; Xu, Zheng; Sun, Qi

    2017-01-01

    Heavy metal wastewater pollution is one of the three major water pollutions in the world. The zinc hydrometallurgy smelting process usually discharge large quantities of heavy metal wastewater into the environment. In this paper, a synergistic solvent extraction process has been developed to recover copper, nickel, zinc and cadmium respectively from calcium and magnesium. The synergistic organic system contained 0.50 M Versatic 10 and 0.5 M Mextral 984H in DT100. Adjusting pH to 2.0 at 40 °C, the copper will be extracted preferentially with the extraction rate more than 99%. Continuing to adjust pH to 4.2 at 40 °C, the nickel will be extracted secondly with an extraction rate more than 98%; the zinc and cadmium in raffinate could be extracted separately while pH is about 6.5.

  9. New evaluation of thermal neutron scattering libraries for light and heavy water

    Directory of Open Access Journals (Sweden)

    Marquez Damian Jose Ignacio

    2017-01-01

    Full Text Available In order to improve the design and safety of thermal nuclear reactors and for verification of criticality safety conditions on systems with significant amount of fissile materials and water, it is necessary to perform high-precision neutron transport calculations and estimate uncertainties of the results. These calculations are based on neutron interaction data distributed in evaluated nuclear data libraries. To improve the evaluations of thermal scattering sub-libraries, we developed a set of thermal neutron scattering cross sections (scattering kernels for hydrogen bound in light water, and deuterium and oxygen bound in heavy water, in the ENDF-6 format from room temperature up to the critical temperatures of molecular liquids. The new evaluations were generated and processable with NJOY99 and also with NJOY-2012 with minor modifications (updates, and with the new version of NJOY-2016. The new TSL libraries are based on molecular dynamics simulations with GROMACS and recent experimental data, and result in an improvement of the calculation of single neutron scattering quantities. In this work, we discuss the importance of taking into account self-diffusion in liquids to accurately describe the neutron scattering at low neutron energies (quasi-elastic peak problem. To improve modeling of heavy water, it is important to take into account temperature-dependent static structure factors and apply Sköld approximation to the coherent inelastic components of the scattering matrix. The usage of the new set of scattering matrices and cross-sections improves the calculation of thermal critical systems moderated and/or reflected with light/heavy water obtained from the International Criticality Safety Benchmark Evaluation Project (ICSBEP handbook. For example, the use of the new thermal scattering library for heavy water, combined with the ROSFOND-2010 evaluation of the cross sections for deuterium, results in an improvement of the C/E ratio in 48 out of

  10. New evaluation of thermal neutron scattering libraries for light and heavy water

    Science.gov (United States)

    Marquez Damian, Jose Ignacio; Granada, Jose Rolando; Cantargi, Florencia; Roubtsov, Danila

    2017-09-01

    In order to improve the design and safety of thermal nuclear reactors and for verification of criticality safety conditions on systems with significant amount of fissile materials and water, it is necessary to perform high-precision neutron transport calculations and estimate uncertainties of the results. These calculations are based on neutron interaction data distributed in evaluated nuclear data libraries. To improve the evaluations of thermal scattering sub-libraries, we developed a set of thermal neutron scattering cross sections (scattering kernels) for hydrogen bound in light water, and deuterium and oxygen bound in heavy water, in the ENDF-6 format from room temperature up to the critical temperatures of molecular liquids. The new evaluations were generated and processable with NJOY99 and also with NJOY-2012 with minor modifications (updates), and with the new version of NJOY-2016. The new TSL libraries are based on molecular dynamics simulations with GROMACS and recent experimental data, and result in an improvement of the calculation of single neutron scattering quantities. In this work, we discuss the importance of taking into account self-diffusion in liquids to accurately describe the neutron scattering at low neutron energies (quasi-elastic peak problem). To improve modeling of heavy water, it is important to take into account temperature-dependent static structure factors and apply Sköld approximation to the coherent inelastic components of the scattering matrix. The usage of the new set of scattering matrices and cross-sections improves the calculation of thermal critical systems moderated and/or reflected with light/heavy water obtained from the International Criticality Safety Benchmark Evaluation Project (ICSBEP) handbook. For example, the use of the new thermal scattering library for heavy water, combined with the ROSFOND-2010 evaluation of the cross sections for deuterium, results in an improvement of the C/E ratio in 48 out of 65

  11. Heavy Metal Assessment in Water and Sediments at Jaikwadi Dam (Godavari River Maharashtra, India

    Directory of Open Access Journals (Sweden)

    Satish S Patil

    2016-05-01

    Full Text Available The indiscriminate release of industrial effluents, domestic sewage, agricultural runoff have resulted in extensive contamination of water and soil with heavy metals thereby causing hazard to flora and fauna and the aquatic ecosystem. Therefore, there is a need for biological monitoring studies to evaluate the toxic concentrations of various chemical compounds so that certain preventive measure can be taken to ensure the safety of the environment. Therefore, this study was focused at investigating few of the important heavy metals like zinc, chromium, cadmium, mercury and lead, in water along with sediments of the Jaikwadi dam. It has been found that the content of mercury was the highest in both water (15.24 - 18.21 μg/L and sediments, it is followed by lead (14.31 - 18.38 μg/L, cadmium (1.95 - 2.29 μg/L, chromium (0.68 - 4.00 μg/L and finally zinc (0.88 - 1.77 μg/L. High concentrations particularly of mercury and lead warrant studies for their remediation so that the concentration remains safe for the populace dependent on the water.INTERNATIONAL JOURNAL OF ENVIRONMENTVolume-5, Issue-2, March-May 2016, Page: 75-88

  12. [Resistance to antibiotics and heavy metals from Escherichia coli isolated from sea water and pluvial galeries].

    Science.gov (United States)

    Cardonha, Angela Maria Soares; Vieira, Regine Helena Silva dos Fernandes; Peirano, Gisele; Rodrigues, Dália dos Prazeres

    2005-01-01

    Test the resistance to antibiotics and heavy metals of E. coli strains isolated from storm sewer water and adjacent seawater samples from three beaches (Meio, Area Preta and Ponta Negra) in the city of Natal/RN/Brazil, and determine the association among those characteristics. A total of 98 strains of E. coli, 50 from storm sewers and 48 from the seawater were analyzed resistance to several antimicrobials by disk diffusion and agar dilution and to heavy metals by dilution in plates with aqueous solutions of CuSO4 incorporated to Mueller Hinton agar in concentrations of 100, 150, 200 and 250 ig/mL and HgCl2 in concentrations of 5, 10, 20, 30, and 50 ig/mL. Standard strains were used as control. Among the twelve antimicrobials tested, 28 (28.5%) of E. coli strains showed resistance to different antimicrobials drugs to seven. The greatest resistance rate was to tetracycline (46.4%), ampicillin (39.3%) and cephalothin (32.1%), with the remainder (nitrophurantoine, nalidixic acid, sulfatomexazol-trimethoprin and chloramphenicol) at lower percentages. Among the heavy metals, all the strains (100%) were resistant to zinc and to copper in the largest concentration (250 ig/mL), and 18.4% were resistant to HgCl the 50 ig/mL. Ten (55.5%) of the E. coli strains resistant to Hg were associated to resistance to antibiotics. These results suggest the existence of extra chromosomal genes in E. coli strains isolated from storm sewer water and adjacent seawater, which encoders of the resistance to antibiotics and heavy metals.

  13. [New methodology for heavy metals measurement in water samples by PGNAA-XRF].

    Science.gov (United States)

    Jia, Wen-Bao; Zhang, Yan; Hei, Da-Qian; Ling, Yong-Sheng; Shan, Qing; Cheng, Can

    2014-11-01

    In the present paper, a new combined detection method was proposed using prompt gamma neutron activation analysis (PGNAA) and characteristic X-ray fluorescence to improve the heavy metals measurement accuracy for in-situ environmental water rejects analysis by PGNAA technology. Especially, the characteristic X-ray fluorescence (XRF) of heavy metals is induced by prompt gamma-ray directly instead of the traditional excitation sources. Thus, a combined measurement facility with an 241 AmBe neutron source, a BGO detector and a NaI-Be detector was developed to analyze the pollutants in water. The two detectors were respectively used to record prompt gamma-ray and characteristic X-ray fluorescence of heavy metals. The prompt gamma-ray intensity (I(γ)) and characteristic X-ray fluorescence intensity (I(x)) was determined by MCNP calculations for different concentration (c(i)) of chromium (Cr), cadmium (Cd), mercury (Hg) and lead (Pb), respectively. The simulation results showed that there was a good linear relationship between I(γ), I(x) and (c(i)), respectively. The empirical formula of combined detection method was given based on the above calculations. It was found that the combined detection method was more sensitive for high atomic number heavy metals like Hg and Pb measurement than low atomic number like Cr and Cd by comparing and analyzing I(γ) and I(x). The limits of detection for Hg and Pb by the combined measurement instrument were 17.4 and 24.2 mg x kg(-1), respectively.

  14. Assessment of Water Quality Index and Heavy Metal Contamination in Active and Abandoned Iron Ore Mining Sites in Pahang, Malaysia

    Directory of Open Access Journals (Sweden)

    Madzin Zafira

    2017-01-01

    Full Text Available The composition of heavy metals in water and surface soils of iron ore mining sites were investigated to evaluate on the potential occurrence of heavy metal contamination. Physico-chemical characteristics of the waters were also investigated to determine the current status of water quality index (WQI of the sites. Samples of water and surface soils of active mine (Kuala Lipis and abandoned mine (Bukit Ibam in Pahang were collected at four locations, respectively. The physico-chemical parameters measured for WQI were pH, dissolved oxygen, biological oxygen demand (BOD, chemical oxygen demand (COD, suspended solids (SS, and ammoniacal nitrogen (AN. The water quality parameters were classified according to the Department of Environment (DOE water quality classification. The study revealed that most of the sites in Bukit Ibam and Kuala Lipis were categorized as clean to slightly polluted. On the other hand, heavy metal analysis in water showed that aluminium and manganese level in both sites have exceeded the allowable limits for raw and treated water standards by the Ministry of Health. For heavy metal compositions in soils showed most of the heavy metal concentrations were below the recommended guideline values except for lead, arsenic, zinc and copper.

  15. Enrichment of steroid hormones in water with porous and hydrophobic polymer-based SPE followed by HPLC-UV determination.

    Science.gov (United States)

    Hu, Yinfen; Zhang, Man; Tong, Changlun; Wu, Jianmin; Liu, Weiping

    2013-10-01

    There have been great concerns about the persistence of steroid hormones in surface water. Since the concentrations of these compounds in water samples are usually at a trace level, the efficient enrichment of steroid hormones is vital for further analysis. In this work, a porous and hydrophobic polymer was synthesized and characterized. The composition of solvent used as porogen in the synthetic process was shown to have an effect on the morphology of the polymer, which was successfully used as an SPE sorbent for simultaneously enriching steroid hormones in surface water samples. The recoveries of the steroid hormones on the custom-made polymer ranged from 93.4 to 106.2%, whereas those on commercialized ENVI-18, LC-18, and Oasis HLB ranged from 54.8 to 104.9, 66 to 93.6, and 77.2 to 106%, respectively. Five types of steroid hormones were simultaneously measured using HPLC-UV after they were enriched by the custom-made sorbent. Based on these findings, the SPE-HPLC method was developed. The LODs of this method for estriol, estradiol, estrone, androstenedione, progesterone were 0.07, 0.43, 0.61, 0.27, and 0.42 μg/L, respectively, while precision and reproducibility RSDs were <6.40 and 7.49%, respectively. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Proposal of new 235U nuclear data to improve keff biases on 235U enrichment and temperature for low enriched uranium fueled lattices moderated by light water

    OpenAIRE

    Wu, H; 奥村 啓介; 柴田 恵一

    2005-01-01

    The under prediction of keff depending on 235U enrichment in low enriched uranium fueled systems was studied in this report. Benchmark testing was carried out with several evaluated nuclear data files, including the new uranium evaluations from preliminary ENDF/B-VII and CENDL-3.1. Another problem reviewed here was keff underestimation vs. temperature increase, which was observed in the slightly enriched system with recent JENDL and ENDF/B uranium evaluations. Through the substitute analysis ...

  17. Seasonal variations in the level of heavy metals in the water of minor rivers

    Directory of Open Access Journals (Sweden)

    I. L. Sukhodolska

    2017-01-01

    Full Text Available This article analyses the level of heavy metals (Zn, Mn, Fe, Pb, Co, Ni, Cd and characteristics of their transportation through the water of minor rivers in Rivne region, Ukraine. The levels of Zn, Cu, Mn, Fe, Ni, Co in the waters of these fisheries exceeded the maximum permissible concentration limit in different months. We found that the concentration of Pb and Cd did not exceed the permissible concentration limit in the waters of the fisheries during the year of research, while the level of other metals exceeded the permissible levels by 1.1 to 151.0 times. This research confirms that the surface waters of Rivne region are characterized by high concentrations of iron, manganese, zinc, and nickel. The level of iron exceeded the maximum permissible concentration limit by 1.1 to 5.0 times, the level of zinc by 1.5 to 15.0 times, that of manganese by1.3 to 6.7 times and the nickel level by 1.3 to 151.0 times in the fishery waters. In principle, the increase in the level of heavy metals (Zn, Cu, Mn, Fe, Ni, Co is connected with the lithological composition of reservoirs in the water-collecting areas of the investigated rivers, and besides with the significant influence of the anthropogenic load (fuel combustion, aqueous wastes of factory units, agricultural effluent, etc., and with the increase in aquatic vegetation, pH balance, temperature change and so on. The appearance of iron-manganese compounds can be explained by natural causes such as reformation of the source minerals into secondary minerals in the conditions of pH level recession in water, which causes the release of these molecular entities; leaching of iron from the iron-manganese septarian nodules, a substantial amount of which is contained in the illuvial horizon. The increase in the level of zinc and nickel in the river water is connected with the leaching of these elements from subsurface rocks, soil and forest leaf litter. Atmospheric condensation is a significant source of the

  18. Heavy Metal Pollution of Chari River Water during the Crossing of N’Djamena (Chad

    Directory of Open Access Journals (Sweden)

    N’garam Nambatingar

    2017-10-01

    Full Text Available This study was carried out to identify and assess the water quality of the Chari River. The Chari, 1200 km long, is Chad’s major water source. Municipal sewage, industrial wastewater discharge, and seasonal run-off from agriculture are regularly fed into the river. Several trace metals such as Cu, Zn, Fe, Ni, Cr, Mn, and Cd, were measured in different sampling stations located along the Chari River at N’Djamena in different campaigns from 2008 to 2010. Overall, manganese, zinc, chromium, and copper concentration levels were mainly in the range of the permissible limits prescribed by WHO guidelines (WHO 2011. Nickel, iron, and cadmium concentrations were still high. This preliminary study allowed us to identify the magnitude of toxic pollutants, which are responsible for Chari River water contamination in the study area. This study revealed that urgent measures must be taken to protect the local people from health problems resulting from high concentrations of heavy metals.

  19. Change of microstructure of clays due to the presence of heavy metal ions in pore water

    Directory of Open Access Journals (Sweden)

    Saiyouri N.

    2010-06-01

    Full Text Available The compressibility of engineered barrier clays is, to a large extent, controlled by microstructure change due to the presence of chemical ions in clay-water system. This paper aims to investigate the change of microstructure of clays due to the presence of heavy metal ions in pore water. We use two pure clays (kaolinite and bentonite in the study. One-dimensional consolidation tests were performed on reconstituted samples, which are prepared with distilled water and three types of heavy metal solutions (Pb(NO32, Cu(NO32, Zn(NO32,. In order to better understand the impact of chemical pore fluid on microstructure of the two clays, following the consolidation test, scanning electron microscope (SEM observations and mercury intrusion pore size distribution measurements (MIP were conducted. Due to the measurement range of MIP, which is only allowed to measure the minimal pore size 20 Å, BET method by gas sorption, whose measurement pore size range is from 3.5 Å to 500 Å, is used to measure the micropore size distribution. By this method, specific surface area of the soils can be also determined. It can be employed to demonstrate the difference of creep performance between the soils. Furthermore, a series of batch equilibrium tests were conducted to better understand the physical-chemical interactions between the particles of soils and the heavy metal ions. With the further consideration of the interparticle electrical attractive and repulsive force, an attempt has been made to predict the creep behaviour by using the modified Gouy-Chapman double layer theory. The results of calculation were compared with that of tests. The comparison shows that the prediction of compressibility of the clays according to the modified double diffuse layer theory can be reasonably agreement with the experimental data.

  20. Heavy metal content of alfalfa irrigated with waste and tubewell water

    Directory of Open Access Journals (Sweden)

    Mohammad Jamal Khan

    2011-11-01

    Full Text Available A field experiment was conducted to study the effect of wastewater on yield and heavy metal uptake of alfalfa along with a tubewell irrigated crop as control at the Agricultural University Peshawar during 2009. The experiment was conducted in small plots (2 x 1m replicated thrice with fertilizer additions. The crop was either irrigated with Hayatabad Industrial Estate (HIE wastewater or tubewell water. The yield data revealed that shoot dry weight was significantly affected by the irrigation water supplies and higher yield was recorded in wastewater irrigated plots and the increase was consistent with time (different cutting. By comparing the total dry biomass of the two treatments, it was observed that there was about 37% increase in yield over control with application of wastewater. The shoot dry weight increased by a factor of about two to three times from first cutting to third cutting in both the treatment plots and the magnitude of increase in yield was higher in wastewater irrigated plots. The heavy metal uptake by the crop was much higher in wastewater irrigated plots compared to tubewell water. The order of metal uptake was Fe> Mn>Zn>Cu>Pb>Ni>Cr>Cd. Shoot analysis showed no metal toxicity because the concentration of the metal was less than phytotoxic level and all the metals were within the permissible limits.

  1. Heavy metals concentration in water and sediments of the Prut River lower sector

    Directory of Open Access Journals (Sweden)

    Matache M. L.

    2013-04-01

    Full Text Available A 120 km sector of the Prut River, Eastern Romania, was surveyed for the concentration of four heavy metals (Cd, Cu, Pb and Zn in water and sediments samples. The analysed sector is located on the border between Romania and Moldova and it is part of the Lower Prut Floodplain Natural Park. The most important steel-producing factory in Romania is located in the park vicinity. Four campaigns have been performed for water collection during different river regimes (both flooding and drought. The water quality is an essential condition for the wetland ecosystems within the park area and the aquatic biota they support, as trace elements bioaccumulation along the food webs might appear (David et al., 2012. Sediments can provide useful information regarding mid- and long-term pollution of the aquatic bodies, being capable of sequestering and releasing important amounts of heavy metals depending on the river regime and extreme situations (van Gestel, 2008; Verhoeven, 2009. For the sediments samples, there is an ascendant trend from upstream to the junction with the Danube River, as the distance to the main urban pole approaches, consequence of a strong human insertion. Romanian standards were used for comparison (MEWM, 2006.

  2. Spatial analysis and health risk assessment of heavy metals concentration in drinking water resources.

    Science.gov (United States)

    Fallahzadeh, Reza Ali; Ghaneian, Mohammad Taghi; Miri, Mohammad; Dashti, Mohamad Mehdi

    2017-11-01

    The heavy metals available in drinking water can be considered as a threat to human health. Oncogenic risk of such metals is proven in several studies. Present study aimed to investigate concentration of the heavy metals including As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in 39 water supply wells and 5 water reservoirs within the cities Ardakan, Meibod, Abarkouh, Bafgh, and Bahabad. The spatial distribution of the concentration was carried out by the software ArcGIS. Such simulations as non-carcinogenic hazard and lifetime cancer risk were conducted for lead and nickel using Monte Carlo technique. The sensitivity analysis was carried out to find the most important and effective parameters on risk assessment. The results indicated that concentration of all metals in 39 wells (except iron in 3 cases) reached the levels mentioned in EPA, World Health Organization, and Pollution Control Department standards. Based on the spatial distribution results at all studied regions, the highest concentrations of metals were derived, respectively, for iron and zinc. Calculated HQ values for non-carcinogenic hazard indicated a reasonable risk. Average lifetime cancer risks for the lead in Ardakan and nickel in Meibod and Bahabad were shown to be 1.09 × 10-3, 1.67 × 10-1, and 2 × 10-1, respectively, demonstrating high carcinogenic risk compared to similar standards and studies. The sensitivity analysis suggests high impact of concentration and BW in carcinogenic risk.

  3. Phytoavailability of heavy metals in tidal flat soils after fresh water leaching.

    Science.gov (United States)

    Li, QuSheng; Chen, XiaoJiao; Luo, Xuan; Cui, ZhiHong; Shi, Lei; Wang, LiLi; Liu, YaNan

    2012-05-01

    The phytoavailability of Cd, Pb, Cr, Zn, Cu, and Ni, retained in tidal flat soil after fresh water leaching during reclamation was investigated. Two salt-tolerant varieties of tomato (Lycopersicon esculentum) and edible amaranth (Amaranthus mangostanus L.) were planted in soils having eight different desalination levels (from 6.7 to 1.4 g kg(-1) salinity) using pot experiments. Soil leaching significantly decreased the uptake of all metals by crop roots except for Ni. The reduction of soil salinity and exchangeable fraction content of Cd and Pb after leaching contributed to the decrease of uptake of metals by roots. All heavy metal concentrations in the edible parts of both crops in the two lowest salinity level treatments were lower than their maximum allowable levels in food. Results suggest that reclamation of tidal flats can reduce the phytoavailability of the heavy metals retained in soil. But the soil heavy metals may still pose health risks in the cultivation of root food crops. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Oil flow in deep waters: comparative study between light oils and heavy oils

    Energy Technology Data Exchange (ETDEWEB)

    Andreolli, Ivanilto [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-12-19

    Ultra deeper waters fields are being exploited due to technological development. Under this scenario, the flow design is accomplished through pipelines subjected to low temperature and high pressure. Moreover, these flow lines are usually long causing a fast fluid cooling, which may affect flow assurance in some cases. Problems during topsides production plant's restart might occur if the oil is viscous and even in steady state a significant different behavior can be noticed, if compared to a less viscous oil. A comparison between light and heavy oil through a case study with the objective to show some heavy oil flow particularities is the purpose of this paper. Permanent and transient analyses for a specific geometry are presented. The results showed that thermal and proper viscosity modeling are required for heavy oil flow, differently from that of light oil flow, due to the exponential viscosity dependence to temperature and because the predominant laminar regime. In addition, on heavier and heavier oil flow systems, it is essential to consider exportation system's restart. (author)

  5. Non-Invasive Acoustic-Based Monitoring of Heavy Water and Uranium Process Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pantea, Cristian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sinha, Dipen N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lakis, Rollin Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Beedle, Christopher Craig [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Davis, Eric Sean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-20

    This presentation includes slides on Project Goals; Heavy Water Production Monitoring: A New Challenge for the IAEA; Noninvasive Measurements in SFAI Cell; Large Scatter in Literature Values; Large Scatter in Literature Values; Highest Precision Sound Speed Data Available: New Standard in H/D; ~400 pts of data; Noninvasive Measurements in SFAI Cell; New funding from NA241 SGTech; Uranium Solution Monitoring: Inspired by IAEA Challenge in Kazakhstan; Non-Invasive Acoustic-Based Monitoring of Uranium in Solutions; Non-Invasive Acoustic-Based Monitoring of Uranium in Solutions; and finally a summary.

  6. Laser-induced synthesis and decay of Tritium under exposure of solid targets in heavy water

    CERN Document Server

    Barmina, E V; Timashev, S F; Shafeev, G A

    2013-01-01

    The processes of laser-assisted synthesis of Tritium nuclei and their laser-induced decay in cold plasma in the vicinity of solid targets (Au, Ti, Se, etc.) immersed into heavy water are experimentally realized at peak laser intensity of 10E10-10E13 Watts per square centimeter. Initial stages of Tritium synthesis and their laser-induced beta-decay are interpreted on the basis of non-elastic interaction of plasma electrons having kinetic energy of 5-10 eV with nuclei of Deuterium and Tritium, respectively.

  7. Natural Jordanian zeolite: removal of heavy metal ions from water samples using column and batch methods.

    Science.gov (United States)

    Baker, Hutaf M; Massadeh, Adnan M; Younes, Hammad A

    2009-10-01

    The adsorption behavior of natural Jordanian zeolites with respect to Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) was studied in order to consider its application to purity metal finishing drinking and waste water samples under different conditions such as zeolite particle size, ionic strength and initial metal ion concentration. In the present work, a new method was developed to remove the heavy metal by using a glass column as the one that used in column chromatography and to make a comparative between the batch experiment and column experiment by using natural Jordanian zeolite as adsorbent and some heavy metals as adsorbate. The column method was used using different metal ions concentrations ranged from 5 to 20 mg/L with average particle size of zeolite ranged between 90 and 350 mum, and ionic strength ranged from 0.01 to 0.05. Atomic absorption spectrometry was used for analysis of these heavy metal ions, the results obtained in this study indicated that zeolitic tuff is an efficient ion exchanger for removing heavy metals, in particular the fine particle sizes of zeolite at pH 6, whereas, no clear effect of low ionic strength values is noticed on the removal process. Equilibrium modeling of the removal showed that the adsorption of Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) were fitted to Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich (DKR). The sorption energy E determined in the DKR equation (9.129, 10.000, 10.541, and 11.180 kJ/mol for Zn(2 + ), Cu(2 + ), Cd(2 + ) and Pb(2 + ) respectively) which revealed the nature of the ion-exchange mechanism.

  8. Heavy metal contamination of stream water and sediment in the Taejon area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung Woong [Paichai University, Taejon (Korea, Republic of); Lee, Hyun Koo [Chungnam National University, Taejon (Korea, Republic of)

    1996-08-31

    Associated with the rapid pace of overpopulation and industrialization is the increase of municipal and industrial wastewater and heavy metal contamination from these point sources have received much attention in the Taejon area. To reduce the environmental problems, 21 stream sediments from Gap-chun, Yudeung-chun, Yusung-chun and Keum river have been analyzed for Cd, Cu, Pb and Zn. The results show that heavy metal concentrations are high in sediments from the Sintanjin and Taehwa Industrial Complex area with particular reference to 1388 {mu}g/g Cu in the stream sediment of Yusung-chun. When the geochemical map drawn from the Kriging technique of these data are compared with the industrialization and urbanization index map, high concentrations of heavy metals are found in stream sediments in industrialized areas resulting from the accumulation of heavy metals from the polluting factories. Concentrations of Cu in sediments from the Taehwa Industrial Complex area and those of Zn in sediments from the Sintanjin Complex area higher than EPA standard in the U.S.A and may be the potential sources of pollution in Keum river with possible implications to human health. For the speciation of Cu, Pb and Zn, the high proportions of exchangeable phase of Cu and Zn in stream sediments indicate that the metals originate not from parent materials but from wastewater and exist as the adsorbed phase on the surface of sediments. These metals are easily dissolved into the water by the reaction and relative amounts of easily dissolved phase of metals are in the order of Cu = Zn > Pb. (author). 17 refs., 4 tabs., 7 figs.

  9. Evaluation of different buffered peptone water (BPW) based enrichment broths for detection of Gram-negative foodborne pathogens from various food matrices

    NARCIS (Netherlands)

    Margot, H.; Zwietering, M.H.; Joosten, H.M.L.J.; O'Mahony, E.; Stephan, R.

    2015-01-01

    This study evaluated the effects of changing the composition of the pre-enrichment medium buffered peptone water (BPW) on the growth of stressed and unstressed Gram-negative foodborne pathogens in a one-broth enrichment strategy. BPW supplemented with an available iron source and sodium pyruvate,

  10. Evaluation of surface water quality indices and ecological risk assessment for heavy metals in scrap yard neighbourhood.

    Science.gov (United States)

    Ojekunle, Olusheyi Z; Ojekunle, Olurotimi V; Adeyemi, Azeem A; Taiwo, Abayomi G; Sangowusi, Opeyemi R; Taiwo, Adewale M; Adekitan, Adetoun A

    2016-01-01

    Pollution of surface water with heavy metals from industrial activities especially those from scrap yard has caused a major threat to human life exposing man to series of hazard, diseases, disability and consequently death. This study focuses on water quality indices of Owode-Onirin and Lafenwa scrap yard with respect to its physicochemical parameters and heavy metal concentrations by evaluating Heavy Metal Pollution Index (HPI), Metal Index (MI) and Potential Ecological Risk Index (PERI). Fifteen water samples were selected randomly from two locations by purposive sampling methods. Five heavy metals which includes Nickel (Ni), Zinc (Zn), Copper (Cu), Cadmium (Cd), Lead (Pb) were analyzed using Atomic Absorption Spectroscopy and standard analytical procedure were follow to ensure accuracy. One way analysis of variance was carried out to analyse the data. The concentrations of the heavy metals were significantly different between sampling locations. However, the mean concentrations of Cd (0.0121 mg/L) were found to be above the highest permissible value of Standard Organization of Nigeria standards for drinking water (SON 2007) and WHO (Guidelines for drinking water quality: incorporating 1st and 2nd Addlenda. World Health Organization, Geneva, 2004) for drinking water. Although Pb was present in two out of the fifteen water samples with a mean value of (0.0324 mg/L) which was also above the highest permissible value. The mean concentrations of Zn (0.2149 mg/L) and Cu (0.0341 mg/L) are found to be below the highest permissible value of the mentioned guideline while no trace of Ni was found in the water samples across the two sampling locations. The mean HPI 518.55 is far above the critical value of 100, indicates that selected water samples are critically polluted with heavy metals. MI revealed low quality water with mean value 4.83, suggests that the selected water is seriously affected with the present of heavy metal. The Hakanson PERI indicated that of the

  11. What is safe and clean water in rural Bolivian communities? A preliminary investigation of heavy metal contamination in rural community water systems in the Bolivian Altiplano

    Science.gov (United States)

    Borella, M.; Guido, Z.; Borella, P.; Ketron, T.

    2009-12-01

    A proliferation of potable water systems utilizing groundwater is currently underway in the Lake Titicaca region of the Bolivian Altiplano. With the aid of national and international organizations, rural communities are developing groundwater sources because the region’s surface water is highly contaminated with waterborne pathogens—the primary factor contributing to high child mortality rates in developing nations. According to UNICEF, 86 percent of Bolivian families have access to “improved” water systems, which predominantly take the form of deep groundwater wells or contained natural springs. While the water systems have worked well to reduce pathogens in drinking water systems that cause illnesses such as dysentery, the water is rarely tested for heavy metal contamination, such as arsenic and lead. While bacteria analysis is essential, it is not the only component of healthy drinking water. Testing for heavy metals is especially important in the Bolivian Altiplano because abundant volcanic deposits and massive sulfide deposits suggest that in some areas it is likely that the water contains elevated concentrations of heavy metals. In this study, Terra Resource Development International, A California-based 502(c)3 nonprofit organization, partnered with Stanford University, the Technical University of Bolivia, and the Bolivian Geologic and Mining Survey to collect water samples in 36 rural community situated in four watersheds feeding into Lake Titicaca. Water was collected from shallow, hand dug wells, deep groundwater wells, springs, and small rivers in the Tiwanku, Laja, Batallas, Achacachi watersheds and were analyzed for inorganic contaminants. Samples were analyzed at Stanford’s Environmental Measurements Facility using the Inductively Coupled Plasma (ICP) Spectrometer for major ions and heavy metals. Results will help determine which, if any, community water systems are at risk of heavy metal contamination, where more comprehensive sampling is

  12. Toxicity detection in water containing heavy metal ions with a self-powered microbial fuel cell-based biosensor.

    Science.gov (United States)

    Yu, Dengbin; Bai, Lu; Zhai, Junfeng; Wang, Yizhe; Dong, Shaojun

    2017-06-01

    In this work, a self-powered microbial fuel cell (MFC)-based biosensor was developed for detecting toxicity in water containing heavy metal ions. Experimental conditions containing concentration of potassium ferricyanide, load resistor and glucose concentration were optimized. Six heavy metal ions (2mg/L, Cu2+, Hg2+, Zn2+, Cd2+, Pb2+ and Cr3+) were tested by this biosensor and the inhibition ratios obtained were 12.56%, 13.99%, 8.81%, 9.29%, 5.59% and 1.95%, respectively. The inhibition ratios of 28.13% was also obtained for detecting the laboratory wastewater containing several heavy metal ions. The experimental results exhibited the feasibility and potential of the self-powered biosensor in detecting toxicities in water containing heavy metal ions. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Oxygen enrichment of sump water by means of plunger valve submerged canal aeration; Sauerstoffanreicherung von Suempfungswaessern mittels Ringkolbenventil-Tauchkanalbeluefung

    Energy Technology Data Exchange (ETDEWEB)

    Poess, Martin [RWE Power AG, Koeln (Germany); Albrecht, Heiko; Schindler, Ingo [RWE Power AG, Bergheim (Germany). Wasserwirtschaft

    2012-07-15

    The discharge of sump water from the Hambach opencast mine into the Erft River requires oxygen enrichment. RWE Power AG for this purpose designed and built an annular plunger valve (APV) submerged canal aeration plant upstream of the discharge point in Bergheim-Thorr for quantities of up to 4.5 m{sup 3}/s that is simultaneously used for rate control of the drainage and supply system in the Rhenisch mining area. The two-line plant utilizes nozzle atomization downstream of the APVs and hydrostatic pressure increase according to the shaft and submerged capal principle to dissolve atmospheric oxygen in water. Successful trial operation proved reliable oxygen enrichment to up to 9 mg/l at water temperatures of approx. 25 C, which, in relation to atmospheric conditions, corresponds to supersaturation of up to 110%. After upcoming commissioning, dissolution in water of a total oxygen quantity of some 600,000 kg per year is expected for a planned discharge quantity of approx. 100 mill. m{sup 3}/a and an average increase in the oxygen concentration by 6 mg/l. (orig.)

  14. Experimental investigation on performance characteristics of a diesel engine using diesel-water emulsion with oxygen enriched air

    Directory of Open Access Journals (Sweden)

    P. Baskar

    2017-03-01

    Full Text Available Diesel engines occupy a crucial position in automobile industry due to their high thermal efficiency and high power to weight ratio. However, they lag behind in controlling air polluting components coming out of the engine exhaust. Therefore, diesel consumption should be analyzed for future energy consumption and this can be primarily controlled by the petroleum fuel substitution techniques for existing diesel engines, which include biodiesel, alcohol-diesel emulsions and diesel water emulsions. Among them the diesel water emulsion is found to be most suitable fuel due to reduction in particulate matter and NOx emission, besides that it also improves the brake thermal efficiency. But the major problem associated with emulsions is the ignition delay, since this is responsible for the power and torque loss. A reduction in NOx emission was observed due to reduction in combustion chamber temperature as the water concentration increases. However the side effect of emulsified diesel is a reduction in power which can be compensated by oxygen enrichment. The present study investigates the effects of oxygen concentration on the performance characteristics of a diesel engine when the intake air is enriched to 27% of oxygen and fueled by 10% of water diesel emulsion. It was found that the brake thermal efficiency was enhanced, combustion characteristics improved and there is also a reduction in HC emissions.

  15. Evaluation of liquid and solid culture media for the recovery and enrichment of Burkholderia cenocepacia from distilled water.

    Science.gov (United States)

    Ahn, Youngbeom; Kim, Jeong Myeong; Ahn, Hyeri; Lee, Yong-Jin; LiPuma, John J; Hussong, David; Cerniglia, Carl E

    2014-07-01

    Burkholderia cepacia complex (BCC) presence has been the cause of recalls of both sterile and non-sterile pharmaceutical products since these opportunistic pathogens have been implicated to cause infections to susceptible individuals. BCC are ubiquitous in nature, but in pharmaceutical settings the most common source is contaminated water systems. Some strains of BCC, previously described as Pseudomonas cepacia, were not readily detected by standard culture methods. We have explored different strategies to recover and enrich Burkholderia cenocepacia previously cultured in distilled water for 40 days. Enrichment media of varied nutrient concentrations and composition were used, including modified Tryptic Soy Agar or Broth (TSA or TSB), Reasoner's 2nd Agar or Broth (R2A or R2AB), Brain-Heart Infusion Broth (BHIB), Mueller-Hinton Broth (MHB), and Ashdown's (ASH) medium. Of the various broth media tested, cell growth was significantly greater in TSB and R2AB than in BHIB, MHB, or ASH broth. TSB and R2AB were also compared for their recovery efficiency. Generally, there was no significant difference between the numbers of B. cenocepacia grown on 15 differently modified TSA and five modified R2A solid media. Overall, however, diluted TSA and TSB media, and R2A and R2AB showed better recovery efficiency than TSA and TSB for inocula containing small numbers of cells. All strains persisted in distilled water for 40 days. Broth media were more effective than solid media for recovery of B. cenocepacia from distilled water. These results may assist in improving detection assays with recovery and enrichment strategies to maximize recovery of these fastidious organisms.

  16. Seismic re-evaluation of piping systems of heavy water plant, Kota

    CERN Document Server

    Mishra, R; Soni, R S; Venkat-Raj, V

    2002-01-01

    Heavy Water Plant, Kota is the first indigenous heavy water plant built in India. The plant started operation in the year 1985 and it is approaching the completion of its originally stipulated design life. In view of the excellent record of plant operation for the past so many years, it has been planned to carry out various exercises for the life extension of the plant. In the first stage, evaluation of operation stresses was carried out for the process critical piping layouts and equipment, which are connected with 25 process critical nozzle locations, identified based on past history of the plant performance. Fatigue life evaluation has been carried out to fmd out the Cumulative Usage Factor, which helps in arriving at a decision regarding the life extension of the plant. The results of these exercises have been already reported separately vide BARC/200I /E/O04. In the second stage, seismic reevaluation of the plant has been carried out to assess its ability to maintain its integ:rity in case of a seismic e...

  17. A high repetition rate laser-heavy water based neutron source

    Science.gov (United States)

    Hah, Jungmoo; He, Zhaohan; Nees, John; Krushelnick, Karl; Thomas, Alexander; CenterUltrafast Optical Science Team

    2015-11-01

    Neutrons have numerous applications in diverse areas, such as medicine, security, and material science. For example, sources of MeV neutrons may be used for active interrogation for nuclear security applications. Recently, alternative ways to generate neutron flux have been studied. Among them, ultrashort laser pulse interactions with dense plasma have attracted significant attention as compact, pulse sources of neutrons. To generate neutrons using a laser through fusion reactions, thin solid density targets have been used in a pitcher-catcher arrangement, using deuterated plastic for example. However, the use of solid targets is limited for high-repetition rate operation due to the need to refresh the target for every laser shot. Here, we use a free flowing heavy water target with a high repetition rate (500 Hz) laser without a catcher. From the interaction between a 10 micron scale diameter heavy water stream with the Lambda-cubed laser system at the Univ. of Michigan (12mJ, 800nm, 35fs), deuterons collide with each other resulting in D-D fusion reactions generating 2.45 MeV neutrons. Under best conditions a time average of ~ 105 n/s of neutrons are generated.

  18. Simulation of water movement and isoproturon behaviour in a heavy clay soil using the MACRO model

    Directory of Open Access Journals (Sweden)

    T. J. Besien

    1997-01-01

    Full Text Available In this paper, the dual-porosity MACRO model has been used to investigate methods of reducing leaching of isoproturon from a structured heavy clay soil. The MACRO model was applied to a pesticide leaching data-set generated from a plot scale experiment on a heavy clay soil at the Oxford University Farm, Wytham, England. The field drain was found to be the most important outflow from the plot in terms of pesticide removal. Therefore, this modelling exercise concentrated on simulating field drain flow. With calibration of field-saturated and micropore saturated hydraulic conductivity, the drain flow hydrographs were simulated during extended periods of above average rainfall, with both the hydrograph shape and peak flows agreeing well. Over the whole field season, the observed drain flow water budget was well simulated. However, the first and second drain flow events after pesticide application were not simulated satisfactorily. This is believed to be due to a poor simulation of evapotranspiration during a period of low rainfall around the pesticide application day. Apart from an initial rapid drop in the observed isoproturon soil residue, the model simulated isoproturon residues during the 100 days after pesticide application reasonably well. Finally, the calibrated model was used to show that changes in agricultural practice (deep ploughing, creating fine consolidated seed beds and organic matter applications could potentially reduce pesticide leaching to surface waters by up to 60%.

  19. Measurement of the Time Dependence of Neutron Slowing-Down and Therma in Heavy Water

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, E.

    1966-03-15

    The behaviour of neutrons during their slowing-down and thermalization in heavy water has been followed on the time scale by measurements of the time-dependent rate of reaction between the flux and the three spectrum indicators indium, cadmium and gadolinium. The space dependence of the reaction rate curves has also been studied. The time-dependent density at 1.46 eV is well reproduced by a function, given by von Dardel, and a time for the maximum density of 7.1 {+-} 0.3 {mu}s has been obtained for this energy in deuterium gas in agreement with the theoretical value of 7.2 {mu}s. The spatial variation of this time is in accord with the calculations by Claesson. The slowing- down time to 0.2 eV has been found to be 16.3 {+-}2.4 {mu}s. The approach to the equilibrium spectrum takes place with a time constant of 33 {+-}4 {mu}s, and the equilibrium has been established after about 200 {mu}s. Comparison of the measured curves for cadmium and gadolinium with multigroup calculations of the time-dependent flux and reaction rate show the superiority of the scattering models for heavy water of Butler and of Brown and St. John over the mass 2 gas model. The experiment has been supplemented with Monte Carlo calculations of the slowing down time.

  20. HEAVY MINERALS IN PLACER DEPOSIT IN SINGKAWANG WATERS, WEST Kalimantan, RELATED TO FELSIC SOURCE ROCK OF ITS COASTAL AREA

    Directory of Open Access Journals (Sweden)

    Deny Setiady

    2017-07-01

    Full Text Available Placer deposits are physically accumulated by fluvial and marine processes in coastal area. Thirty six samples were selected from seventy seven samples of seafloor sediment of Singkawang waters. Those samples have been analyzed microscopically for heavy mineral contents. Based on this analysis, the heavy minerals can be divided into four groups: oxyde and hydroxyde, silicate, sulphide, and carbonate. The source of most heavy minerals in the study area is commonly formed by Felsic igneous rock and finally deposited on the seafloor sediments.

  1. SPECIATION OF HEAVY METALS IN SURFACE WATERS POLLUTED BY ANTHROPOGENIC ACTIVITIES

    Directory of Open Access Journals (Sweden)

    Constantin Luca

    2010-12-01

    Full Text Available In this work we present the results of a methodological research on the chemical speciation of heavy metals found in surface waters of an area polluted by mining activities (in the Western Carpathians. The surface water samples were collected in two seasons (summer and fall. Each time were performed in situ physical-chemical measurements (pH, Eh, conductivity, temperature and analytical determination of total concentrations of some metals (manganese, copper, zinc, iron, cadmium and anions (SO42-, Cl-, PO43-, NO3-. Analyze of chemical speciation of these metals was made using the PHREEQC program which allowed us to determine the distribution of studied elements. The concordance of the results obtained with this program with thermodynamic predictions arising from potential - pH equilibrium diagrams - Pourbaix type justify the compatibility between the program calculation and experimental data.

  2. Health risk assessment of heavy metals in wheat using different water qualities: implication for human health.

    Science.gov (United States)

    Khan, Zafar Iqbal; Ahmad, Kafeel; Rehman, Sidrah; Siddique, Samra; Bashir, Humayun; Zafar, Asma; Sohail, Muhammad; Ali, Salem Alhajj; Cazzato, Eugenio; De Mastro, Giuseppe

    2017-01-01

    In the recent years, the use of sewage water for irrigation has attracted the attention of arid and semi-arid countries where the availability of fresh water is poor. Despite the potential use of sewage water in crop irrigation as effective and sustainable strategy, the environmental and human risks behind this use need to be deeply investigated. In this regard, an experiment was carried out under field conditions in Nursery, University College of Agriculture Sargodha, to evaluate the possible health risks of undesirable metals in wheat grains. Wheat variety Sarang was cultivated and irrigated with different combinations of ground (GW) and sewage water (SW). The concentrations of heavy metals (Cr, Cd, Ni, and Pb) and trace elements (Cu, Zn, and Fe) in wheat grains as well as in soil were determined. Moreover, the pollution load index (PLI), accumulation factor (AF), daily intake of metals (DIM), and health risk index (HRI) were calculated. Results showed that the concentration trend of heavy metals was Pbwater quality, whereas Pb concentration in grain was within the acceptable levels as suggested by World Health Organization, when 100 % of SW was used for irrigation. Similar observation was reported for Cd concentration in the soil when wheat was irrigated with 100 % SW. In comparison to soil, the edible part of wheat presented lower concentration of all studied metals, except for Zn which was much higher compared to the tested soil samples. The higher concentration of Zn was responsible for increasing the DIM of Zn where, in average, the highest value was reported, particularly in 75 % SW treatment. This was reflected also in HRI where the maximum value was reported for Zinc under the same treatment. Higher value of HRI for wheat cultivated on polluted soils suggested that appropriate management of cultivated area is necessary for food safety and thus for public health. The results are expected to create awareness among the public on the safety of consuming

  3. Low-dose whey protein-enriched water beverages alter satiety in a study of overweight women.

    Science.gov (United States)

    Poppitt, Sally D; Proctor, Janie; McGill, Anne-Thea; Wiessing, Katy R; Falk, Sofie; Xin, Liping; Budgett, Stephanie C; Darragh, Alison; Hall, Ramon S

    2011-04-01

    To determine the effect of low-dose whey protein-enriched water beverages on postprandial satiety and energy intake (EI). Fifty overweight and mildly obese women were given 500 mL water-based beverages on 4 different occasions in a double blind, cross-over study. The beverages were reasonably matched for colour, flavour, sweetness and contained 0% (water control, 0 g, 8 kJ), 1% (5 g, 93 kJ), 2% (10 g, 178 kJ) and 4% (20 g, 348 kJ) whey protein by weight (ClearProtein8855™). Following a standard evening meal and breakfast, beverages were consumed 120 min before an ad libitum lunch at which EI was measured. Feelings associated with hunger and fullness were also measured using visual analogue scales (VAS). 46 participants completed all 4 beverage conditions. There was a significant effect of beverage preload on hunger (beverage×time; P=0.0074), where each of the 1%, 2% and 4% w/w protein beverages decreased hunger compared to the water control (Pbeverages (Friedman test, P=0.013). Fullness (beverage×time; P=0.0020) and satisfaction (beverage×time; P=0.0356) were both increased by the 1% and 4% protein beverages (P0.05) when escalating protein doses were added to the water preload (water control, 3028 kJ; 1%, 3080 kJ; 2%, 2924 kJ; 4%, 2781 kJ), only partial compensation for the added energy. These low-dose, whey protein-enriched water beverages significantly altered short term postprandial satiety, however the effect was not sufficient to impact on food intake when assessed 2 h after consumption. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Distributions and pollution assessment of heavy metals Pb, Cd and Cr in the water system of Kendari Bay, Indonesia

    Science.gov (United States)

    Armid, A.; Shinjo, R.; Ruslan, R.; Fahmiati

    2017-02-01

    The concentrations of heavy metals Pb, Cd and Cr in the coastal waters of Kendari Bay were analyzed to assess their pollution status. Water samples from 32 sampling points were analyzed for dissolved heavy metals concentrations by using inductively coupled plasma mass spectrometry (ICP-MS). The RSD(%) of each metal was accounted to analyze the diversity of the heavy metals among 32 sampling points. The results demonstrate that the dissolved heavy metal Pb had the highest concentrations (0.009 to 0.549 μg/L, average = 0.210 μg/L) followed by Cr (0.085 to 0.386 μg/L, average = 0.149 μg/L), and Cd (0.001 to 0.015 μg/L, average = 0.008 μg/L). Based on the the RSD values (Pb = 87.8%, Cd = 45.2% and Cr = 41.3%), it is suggested that the antropogenic activities controls the high diversity of concentrations for heavy metal Pb relative to those of Cd and Cr. Comparing the data with the mean oceanic concentrations, only the concentrations of Pb exceed the mean oceanic level (210 folds). Therefore, the water system of Kendari Bay is severely polluted with heavy metal Pb. More management and treatment should be introduced to protect the marine environment in the study area, especially from Pb pollution.

  5. Utilization of coal-water liquid fuel mixtures in heavy fuel oil burning boiler installations

    Energy Technology Data Exchange (ETDEWEB)

    Vuletic, V. (Rudarski Institut, Belgrade (Yugoslavia). Zavod za Termotehniku)

    1989-01-01

    Describes preliminary laboratory tests carried out to assess the feasibility of a project to be organized by the Mining Institute of Belgrade on construction of a pilot semi-industrial plant to investigate substitution of heavy fuel oil used in many thermal power plants with a coal/water or coal/water/oil mix. Tests were conducted using brown coal from the Kolubara surface mine made up in three formats: coal powder/water, coal powder/fuel oil and coal powder/water/fuel oil. Thermodynamic computations were made on each mix in order to predict their effectiveness when used to fuel TE-101 and TE-106 steam generating boilers that would normally consume 1 and 5 t fuel oil per hour respectively. Results are presented in tabular form. Concludes that the coal/oil and coal/oil/water mixes could be used as a substitute fuel with only minor modifications necessary to the boilers. Recommends proceeding with pilot plant construction. 4 refs.

  6. Removal heavy metals and sulphate from waste waters by sulphate-reducing bacteria

    Directory of Open Access Journals (Sweden)

    Kušnierová Mária

    2000-09-01

    Full Text Available This article is devoted to the process of bacterial sulphate reduction, which is used to removal of heavy metals and sulphate ions from waste waters.The life of animals and plants depends on the existence of microscopic organisms – microorganisms (MO, which play an important role in cycle changes of biogenic elements on the earth. The sulphur cycle in the nature is considered as one of the oldest and most significant biological systems (Fig. 1. The sulphate-reducing bacteria (SRB miss the assimilatory part of the cycle and produce sulphides. The microbial population of this dissimilatory part is called “sulfuretum”. The SRB can be found in anaerobic mud and sediments of freshwater, thermal or non-thermal sulphur springs, mining waters from sulphide deposits, oil deposits, sea and ocean beds, and in the gastrointestinal tract of man and animals. The SRB represent a group of chemoorganotrophic, strictly anaerobic and gramnegative bacteria, which exhibit a great morphological and physiological diversity. Despite of their considerable morphological variety, they have one property in common, which is the ability to utilise preferentially sulphates (occasionally sulphites, thiosulphates, tetrathionates as electron acceptors, which are reduced to sulphides, during anaerobic respiration. The electron donors in these processes are simple organic compounds as lactate, malate, etc.,(heterotrophically reduction or gaseous hydrogen (autotrophically reduction. SRB can produce a considerable amount of hydrogen sulphide, which reacts easily in aqueous solution with the cations of heavy metals, forming metal sulphides that have low solubility. The bacterial sulphate reduction can be used for the treatment of acid mine drainage waters, which is considered to be the major problem associated with mining activities.In order to remove heavy metals from waste waters, e.g., from galvanizing plants, mine waters (Smolnik, Šobov locality and metallurgic plants (works

  7. Measurement of extremely (2) H-enriched water samples by laser spectrometry: application to batch electrolytic concentration of environmental tritium samples.

    Science.gov (United States)

    Wassenaar, L I; Kumar, B; Douence, C; Belachew, D L; Aggarwal, P K

    2016-02-15

    Natural water samples artificially or experimentally enriched in deuterium ((2) H) at concentrations up to 10,000 ppm are required for various medical, environmental and hydrological tracer applications, but are difficult to measure using conventional stable isotope ratio mass spectrometry. Here we demonstrate that off-axis integrated cavity output (OA-ICOS) laser spectrometry, along with (2) H-enriched laboratory calibration standards and appropriate analysis templates, allows for low-cost, fast, and accurate determinations of water samples having δ(2) HVSMOW-SLAP values up to at least 57,000 ‰ (~9000 ppm) at a processing rate of 60 samples per day. As one practical application, extremely (2) H-enriched samples were measured by laser spectrometry and compared to the traditional (3) H Spike-Proxy method in order to determine tritium enrichment factors in the batch electrolysis of environmental waters. Highly (2) H-enriched samples were taken from different sets of electrolytically concentrated standards and low-level (enriched waters by laser spectrometry will facilitate the use of deuterium as a tracer in numerous environmental and other applications. For low-level tritium operations, this new analytical ability facilitated a 10-20 % increase in sample productivity through the elimination of spike standards and gravimetrics, and provides immediate feedback on electrolytic enrichment cell performance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. SURFACE WATER POLLUTION WITH HEAVY METALS IN THE LOWER CATCHMENT OF JIU RIVER BASIN, ACCORDING TO THE WATER FRAMEWORK DIRECTIVE (2000/60/EC

    Directory of Open Access Journals (Sweden)

    ADINA SANDA ŞERBAN

    2011-03-01

    Full Text Available Surface water pollution with heavy metals in the lower catchment of Jiu river basin, according to the Water Framework Directive (2000/60/EC. The Water Framework Directive establishes a single transparent, effective and coherent water policy by defining a strategy to combat pollution by requiring specific action programs.Chemical pollution of surface water presents a threat to the aquatic environment with acute and chronic toxicity to aquatic organisms, accumulation in the ecosystem and losses of habitats and biodiversity, as well as a threat to human health (art.1 from Directive 2008/105/EC regarding the environmental quality standards for water policy.The purpose of this study is to evaluate the chemical status for surface water bodies in the lower catchment of Jiu river basin. The assessment was made taking into account the water impact of four heavy metals: cadmium (Cd, nickel (Ni, mercury (Hg and lead (Pb.

  9. Multiple stressors in agricultural streams: a mesocosm study of interactions among raised water temperature, sediment addition and nutrient enrichment.

    Directory of Open Access Journals (Sweden)

    Jeremy J Piggott

    Full Text Available Changes to land use affect streams through nutrient enrichment, increased inputs of sediment and, where riparian vegetation has been removed, raised water temperature. We manipulated all three stressors in experimental streamside channels for 30 days and determined the individual and pair-wise combined effects on benthic invertebrate and algal communities and on leaf decay, a measure of ecosystem functioning. We added nutrients (phosphorus+nitrogen; high, intermediate, natural and/or sediment (grain size 0.2 mm; high, intermediate, natural to 18 channels supplied with water from a nearby stream. Temperature was increased by 1.4°C in half the channels, simulating the loss of upstream and adjacent riparian shade. Sediment affected 93% of all biological response variables (either as an individual effect or via an interaction with another stressor generally in a negative manner, while nutrient enrichment affected 59% (mostly positive and raised temperature 59% (mostly positive. More of the algal components of the community responded to stressors acting individually than did invertebrate components, whereas pair-wise stressor interactions were more common in the invertebrate community. Stressors interacted often and in a complex manner, with interactions between sediment and temperature most common. Thus, the negative impact of high sediment on taxon richness of both algae and invertebrates was stronger at raised temperature, further reducing biodiversity. In addition, the decay rate of leaf material (strength loss accelerated with nutrient enrichment at ambient but not at raised temperature. A key implication of our findings for resource managers is that the removal of riparian shading from streams already subjected to high sediment inputs, or land-use changes that increase erosion or nutrient runoff in a landscape without riparian buffers, may have unexpected effects on stream health. We highlight the likely importance of intact or restored buffer

  10. Multiple stressors in agricultural streams: a mesocosm study of interactions among raised water temperature, sediment addition and nutrient enrichment.

    Science.gov (United States)

    Piggott, Jeremy J; Lange, Katharina; Townsend, Colin R; Matthaei, Christoph D

    2012-01-01

    Changes to land use affect streams through nutrient enrichment, increased inputs of sediment and, where riparian vegetation has been removed, raised water temperature. We manipulated all three stressors in experimental streamside channels for 30 days and determined the individual and pair-wise combined effects on benthic invertebrate and algal communities and on leaf decay, a measure of ecosystem functioning. We added nutrients (phosphorus+nitrogen; high, intermediate, natural) and/or sediment (grain size 0.2 mm; high, intermediate, natural) to 18 channels supplied with water from a nearby stream. Temperature was increased by 1.4°C in half the channels, simulating the loss of upstream and adjacent riparian shade. Sediment affected 93% of all biological response variables (either as an individual effect or via an interaction with another stressor) generally in a negative manner, while nutrient enrichment affected 59% (mostly positive) and raised temperature 59% (mostly positive). More of the algal components of the community responded to stressors acting individually than did invertebrate components, whereas pair-wise stressor interactions were more common in the invertebrate community. Stressors interacted often and in a complex manner, with interactions between sediment and temperature most common. Thus, the negative impact of high sediment on taxon richness of both algae and invertebrates was stronger at raised temperature, further reducing biodiversity. In addition, the decay rate of leaf material (strength loss) accelerated with nutrient enrichment at ambient but not at raised temperature. A key implication of our findings for resource managers is that the removal of riparian shading from streams already subjected to high sediment inputs, or land-use changes that increase erosion or nutrient runoff in a landscape without riparian buffers, may have unexpected effects on stream health. We highlight the likely importance of intact or restored buffer strips, both

  11. Speciation of heavy metals in coastal water of Qeshm Island in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    A.R. Karbassi

    2018-01-01

    Full Text Available Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries.  In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable hydrocarbons. Oil type, climatic condition and characteristics of oil tanks are among the main variables in computing evaporative losses. The present study brings out the results of a project that was carried out to investigate the adverse effects of oil terminal on coastal waters of Qeshm Island and aims to elaborate on speciation of metals in coastal waters. For this purpose, 12 stations were sampled. Water chemistry software was used to draw Eh-pH diagrams. Along with the speciation of heavy metals, cluster analysis was carried out by MVSP software. According to the results, HSC diagrams showed that Cu and Cd were present as free ions. Lead, manganese, cobalt, zinc and nickel were respectively present as PbOH, MnOH, ZnOH, CoOH and NiOH in the Persian Gulf. Speciation of Cu and Ni was in the form of Cu2O and NiO. Vanadium was also present in combination with hydroxide. Since all the studied elements were within the water stability range, they were stable, and there were no environmental risks of contamination and toxicity. The results of cluster analysis did not show any relation between Eh and pH. This clearly showed that Eh-pH was governed by different mechanisms in coastal waters of Qeshm Island. Vanadium and Ni concentration was governed by pH, while Cu and Cd concentration was controlled by Eh.

  12. Contribution of GIS to evaluate surface water pollution by heavy metals: Case of Ichkeul Lake (Northern Tunisia)

    Science.gov (United States)

    Yazidi, Amira; Saidi, Salwa; Ben Mbarek, Nabiha; Darragi, Fadila

    2017-10-01

    The concentrations of nutrients and heavy elements in the surface water of the lake Ichkeul, main wadis which feed directly and thermal springs that flow into the lake, are measured to evaluate these chemical elements. There are used to highlight the interactions between these different aquatic compartments of Ichkeul. All metal concentrations in lake water, except Cu, were lower than the maximum permitted concentration for the protection of aquatic life. The results show that the highest concentrations are located in the eastern and south-eastern part of the lake where the polluted water comes from the lagoon of Bizerte through the wadi Tinja as well as from the city of Mateur through the wadi Joumine. The pollution indices and especially the heavy metal evaluation index (HEI) show high pollution specially located at the mouths of wadis and an increase of heavy metal concentrations, as a result of uncontrolled releases of domestic and industrial wastewater.

  13. Combine the soil water assessment tool (SWAT) with sediment geochemistry to evaluate diffuse heavy metal loadings at watershed scale.

    Science.gov (United States)

    Jiao, Wei; Ouyang, Wei; Hao, Fanghua; Huang, Haobo; Shan, Yushu; Geng, Xiaojun

    2014-09-15

    Assessing the diffuse pollutant loadings at watershed scale has become increasingly important when formulating effective watershed water management strategies, but the process was seldom achieved for heavy metals. In this study, the overall temporal-spatial variability of particulate Pb, Cu, Cr and Ni losses within an agricultural watershed was quantitatively evaluated by combining SWAT with sediment geochemistry. Results showed that the watershed particulate heavy metal loadings displayed strong variability in the simulation period 1981-2010, with an obvious increasing trend in recent years. The simulated annual average loadings were 20.21 g/ha, 21.75 g/ha, 47.35 g/ha and 21.27 g/ha for Pb, Cu, Cr and Ni, respectively. By comparison, these annual average values generally matched the estimated particulate heavy metal loadings at field scale. With spatial interpolation of field loadings, it was found that the diffuse heavy metal pollution mainly came from the sub-basins dominated with cultivated lands, accounting for over 70% of total watershed loadings. The watershed distribution of particulate heavy metal losses was very similar to that of soil loss but contrary to that of heavy metal concentrations in soil, highlighting the important role of sediment yield in controlling the diffuse heavy metal loadings. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Drinking water studies: a review on heavy metal, application of biomarker and health risk assessment (a special focus in Malaysia).

    Science.gov (United States)

    Ab Razak, Nurul Hafiza; Praveena, Sarva Mangala; Aris, Ahmad Zaharin; Hashim, Zailina

    2015-12-01

    Malaysia has abundant sources of drinking water from river and groundwater. However, rapid developments have deteriorated quality of drinking water sources in Malaysia. Heavy metal studies in terms of drinking water, applications of health risk assessment and bio-monitoring in Malaysia were reviewed from 2003 to 2013. Studies on heavy metal in drinking water showed the levels are under the permissible limits as suggested by World Health Organization and Malaysian Ministry of Health. Future studies on the applications of health risk assessment are crucial in order to understand the risk of heavy metal exposure through drinking water to Malaysian population. Among the biomarkers that have been reviewed, toenail is the most useful tool to evaluate body burden of heavy metal. Toenails are easy to collect, store, transport and analysed. This review will give a clear guidance for future studies of Malaysian drinking water. In this way, it will help risk managers to minimize the exposure at optimum level as well as the government to formulate policies in safe guarding the population. Copyright © 2015 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  15. Characteristics of a heavy water photoneutron source in boron neutron capture therapy

    Science.gov (United States)

    Danial, Salehi; Dariush, Sardari; M. Salehi, Jozani

    2013-07-01

    Bremsstrahlung photon beams produced by medical linear accelerators are currently the most commonly used method of radiation therapy for cancerous tumors. Photons with energies greater than 8-10 MeV potentially generate neutrons through photonuclear interactions in the accelerator's treatment head, patient's body, and treatment room ambient. Electrons impinging on a heavy target generate a cascade shower of bremsstrahlung photons, the energy spectrum of which shows an end point equal to the electron beam energy. By varying the target thickness, an optimum thickness exists for which, at the given electron energy, maximum photon flux is achievable. If a source of high-energy photons i.e. bremsstrahlung, is conveniently directed to a suitable D2O target, a novel approach for production of an acceptable flux of filterable photoneturons for boron neutron capture therapy (BNCT) application is possible. This study consists of two parts. 1. Comparison and assessment of deuterium photonuclear cross section data. 2. Evaluation of the heavy water photonuclear source.

  16. Response of lettuce to Cd-enriched water and irrigation frequencies

    African Journals Online (AJOL)

    hope&shola

    be the most sensitive parameters to the cadmium, especially under water stress conditions. The results also showed that the concentrations of nutrient elements in lettuce shoot were suppressed by water stress. The presence of cadmium in irrigation water did not ..... an increase in Fe concentration in tomato and a decrease.

  17. Heavy Metals (Cu, Pb and Cd) in Water and Angel Fish (Chelmon rostractus) from Batam Coastal, Indonesia

    OpenAIRE

    Ismarti Ismarti; Ramses Ramses; Suheryanto Suheryanto; Fitrah Amelia

    2017-01-01

    Fish play an important role in human nutrition and therefore need to be carefully and routinely monitored to ensure that there are no high levels of heavy metals being transferred to human through their consumption. This study has been carried out to determine level of heavy metals (Cu, Pb, and Cd) in water and angel fish, Chelmon rostractus collected from coast of Batam. We report levels of Cu, Cd and Pb in water and angel fish from Coast Batam using Atomic Absorption Spectroscopy (AAS). Lev...

  18. Application of gas chromatography-tandem mass spectrometry (GC/MS/MS) for the analysis of deuterium enrichment of water.

    Science.gov (United States)

    Walker, Dillon K; Thaden, John J; Deutz, Nicolaas E P

    2015-06-01

    Incorporation of deuterium from deuterium oxide ((2) H2 O) into biological components is a commonly used approach in metabolic studies. Determining the dilution of deuterium in the body water (BW) pool can be used to estimate body composition. We describe three sensitive GC/MS/MS methods to measure water enrichment in BW. Samples were reacted with NaOH and U-(13) C3 -acetone in an autosampler vial to promote deuterium exchange with U-(13) C3 -acetone hydrogens. Headspace injections were made of U-(13) C3 -acetone-saturated air onto a 30-m DB-1MS column in electron impact-mode. Subjects ingested 30 ml (2) H2 O, and plasma samples were collected. BW was determined by standard equation. Dual-energy X-ray absorptiometry scans were performed to calculate body mass, body volume and bone mineral content. A four-compartmental model was used to estimate body composition (fat and fat free mass). Full-scan experiments generated an m/z 45 peak and to a lesser extent an m/z 61 peak. Product fragment ions further monitored included 45 and 46 using selected ion monitoring (Method1), the 61 > 45 and 62 > 46 transition using multiple reaction monitoring (MRM; Method2) and the neutral loss, 62 > 45, transition (Method3). MRM methods were optimized for collision energy (CE) and collision-induced dissociation (CID) argon gas pressure with 6 eV CE and 1.5 mTorr CID gas being optimal. Method2 was used for final determination of (2) H2 O enrichment of subjects because of lower natural background. We have developed a sensitive method to determine (2) H2 O enrichment in BW to enable measurement of FM and FFM. Copyright © 2015 John Wiley & Sons, Ltd.

  19. Biomarkers and heavy metal bioaccumulation in mussels transplanted to coastal waters of the Beagle Channel.

    Science.gov (United States)

    Giarratano, Erica; Duarte, Claudia A; Amin, Oscar A

    2010-03-01

    Mussels coming from a mussel farm at Brown Bay (Beagle Channel) were transplanted to four sites inside Ushuaia Bay for 2 and 4 weeks. The objective of this study was to assess the quality of coastal waters of Ushuaia Bay by measuring catalase activity, lipid peroxidation, total lipid content, bioaccumulation of heavy metals and condition index in transplanted mussel Mytilus edulis chilensis. Biomarkers except condition index showed significant differences among exposure times as well as among tissues. Digestive gland presented the highest catalase activity, malondialdehyde level and total lipid content. Digestive gland also was the main target tissue of accumulation of iron and copper, while gill accumulated the highest levels of zinc. A principal component analyzes with the whole set of data allowed to separate stations based on physicochemical conditions and biochemical responses of each studied area. (c) 2009 Elsevier Inc. All rights reserved.

  20. Removal of Heavy Metals from Steel Making Waste Water by Using Electric Arc Furnace Slag

    Directory of Open Access Journals (Sweden)

    C. L. Beh

    2012-01-01

    Full Text Available This work investigated the reduction of chemical oxygen demand (COD, biological oxygen demand (BOD, total suspended solids (TSS and the concentration of heavy metals of wastewater from a steel making plant. Adsorption experiments were carried out by electric arc furnace slag (EAFS in a fixed-bed column mode. The raw wastewater did not meet the standard B limitations, having high values of BOD, COD, TSS, Iron, Zinc, Manganese and Copper. After passing through the fixed bed column, BOD, COD and TSS values decreased to 1.6, 6.3 and <2 mgL-1, respectively while the concentration of Iron, Zinc, Manganese and Copper were 0.08, 0.01, 0.03 and 0.07 mgL-1, respectively. The results confirmed that EAFS can be used as an efficient adsorbent for producing treated water that comply with the Standard B limitations for an industrial effluent.

  1. Power level effects on thorium-based fuels in pressure-tube heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bromley, B.P.; Edwards, G.W.R., E-mail: blair.bromley@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Sambavalingam, P. [Univ. of Ontario Inst. of Technology, Oshawa, Ontario (Canada)

    2016-06-15

    Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels on the reactivity and achievable burnup for 35-element fuel bundles made with Pu/Th or U-233/Th. The fissile content in these bundles has been adjusted to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700 MWe-class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Results demonstrate that the impact of the power/flux level is modest for Pu/Th fuels but significant for U-233/Th fuels. In particular, high power/flux reduces the breeding and burnup potential of U-233/Th fuels. Thus, there may be an incentive to operate reactors with U-233/Th fuels at a lower power density or to develop alternative refueling schemes that will lower the time-average specific power, thereby increasing burnup.(author)

  2. Core loading pattern optimization of thorium fueled heavy water breeder reactor using genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Soewono, C. N.; Takaki, N. [Dept. of Applied Science Engineering, Faculty Tokai Univ., Kanagawa-ken, Hiratsuka-shi Kitakaname 4-1-1 (Japan)

    2012-07-01

    In this work genetic algorithm was proposed to solve fuel loading pattern optimization problem in thorium fueled heavy water reactor. The objective function of optimization was to maximize the conversion ratio and minimize power peaking factor. Those objectives were simultaneously optimized using non-dominated Pareto-based population ranking optimal method. Members of non-dominated population were assigned selection probabilities based on their rankings in a manner similar to Baker's single criterion ranking selection procedure. A selected non-dominated member was bred through simple mutation or one-point crossover process to produce a new member. The genetic algorithm program was developed in FORTRAN 90 while neutronic calculation and analysis was done by COREBN code, a module of core burn-up calculation for SRAC. (authors)

  3. Water radiolysis with heavy-ion beams at GANIL. Back to 20 years of investigations

    Science.gov (United States)

    Baldacchino, G.

    2015-07-01

    This article reports a short history of the studies carried out in the domain of radiation chemistry with the swift heavy ions of GANIL (Grand Accélérateur National d'lons Lourds) during the last 20 years. The originality of these studies lays on two main aspects which were never been investigated simultaneously before: 1) the energy of the GANIL ions provides an energy deposition in small samples (few millimeters) that can be considered as almost constant; this allows studies on LET-effect on radiolytic yields, 2) production of pulses as short as a few nanoseconds made available the access to pulse radiolysis method and the study of transient chemical species such as hydrated electron, hydroxyl radical and superoxide. Future is now focus on high temperature effects on water radiolysis for which, again, nothing exist but only simulations and speculations.

  4. Pyruvate-enriched oral rehydration solution improved intestinal absorption of water and sodium during enteral resuscitation in burns.

    Science.gov (United States)

    Hu, Sen; Liu, Wei-wei; Zhao, Ying; Lin, Zhi-long; Luo, Hong-min; Bai, Xiao-dong; Sheng, Zhi-yong; Zhou, Fang-qiang

    2014-06-01

    To investigate alteration in intestinal absorption during enteral resuscitation with pyruvate-enriched oral rehydration solution (Pyr-ORS) in scalded rats. To compare pyruvate-enriched oral rehydration solution (Pyr-ORS) with World Health Organisation oral rehydration solution (WHO-ORS), 120 rats were randomly divided into 6 groups and 2 subgroups. At 1.5 and 4.5 h after a 35% TBSA scald, the intestinal absorption rate, mucosal blood flow (IMBF), Na(+)-K(+)-ATPase activity and aquaporin-1 (AQP-1) expression were determined (n = 10), respectively. The intestinal Na(+)-K(+)-ATPase activity, AQP-1 expression and IMBF were markedly decreased in scald groups, but they were profoundly preserved by enteral resuscitation with WHO-ORS and further improved significantly with Pyr-ORS at both time points. Na(+)-K+-ATPase activities remained higher in enteral resuscitation with Pyr-ORS (Group SP) than those with WHO-ORS (Group SW) at 4.5 h. AQP-1 and IMBF were significantly greater in Group SP than in Group SW at both time points. Intestinal absorption rates of water and sodium were obviously inhibited in scald groups; however, rates were also significantly preserved in Group SP than in Group SW with an over 20% increment at both time points. The Pyr-ORS may be superior to the standard WHO-ORS in the promotion of intestinal absorption of water and sodium during enteral resuscitation. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  5. Nanoscale zero-valent iron functionalized Posidonia oceanica marine biomass for heavy metal removal from water.

    Science.gov (United States)

    Boubakri, Saber; Djebbi, Mohamed Amine; Bouaziz, Zaineb; Namour, Philippe; Ben Haj Amara, Abdesslem; Ghorbel-Abid, Ibtissem; Kalfat, Rafik

    2017-12-01

    Because of the excellent reducing capacity of nanoscale zero-valent iron (NZVI), it can be used as alternative materials for the removal of a variety of reducible water contaminants including toxic metals. The current paper reports the research results obtained for self-prepared biosorbent, Posidonia oceanica biomass, activated in alkaline medium and functionalized with NZVI particles. The structural characteristics, surface morphology, and binding properties of the resulting nanobiosorbent are presented. Batch comparative adsorption trials including adsorption kinetics and isothermals onto raw Posidonia, Posidonia-OH and Posidonia-OH-NZVI were investigated on three heavy metal ions: Cd(II), Pb(II), and Cu(II). The nanobiosorbent showed better properties, such as high reactivity and high uptake rate through the sorption process. The toxic metal removal has been monitored in terms of pseudo-first- and pseudo-second-order kinetics, and both Langmuir- and Freundlich-type isotherm models have been used to describe the sorption mechanism. The experimental data of all studied systems showed that the uptake kinetics follow the pseudo-second-order kinetic model and the equilibrium uptake can adopt the Langmuir-type isotherm model which assumes a monolayer coverage as the adsorption saturates and no further adsorption occurs. The thermodynamic results confirm that all sorption processes were feasible, spontaneous and thermodynamically favorable. Zeta potential data displayed that Cd(II), Pb(II), and Cu(II) tend to be reduced after exposure on the Posidonia-OH-NZVI surface. Furthermore, sorption competitions of the metals from binary and ternary systems were carried out onto Posidonia-OH-NZVI in order to gain further insight into the sorption efficiency of this material. Therefore, as a result, the proposed new nanobiosorbent could offer potential benefits in remediation of heavy metal-contaminated water as a green and environmentally friendly bionanocomposite.

  6. Application of Genetic Algorithm methodologies in fuel bundle burnup optimization of Pressurized Heavy Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jayalal, M.L., E-mail: jayalal@igcar.gov.in [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Ramachandran, Suja [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Rathakrishnan, S. [Reactor Physics Section, Madras Atomic Power Station (MAPS), Kalpakkam, Tamil Nadu (India); Satya Murty, S.A.V. [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Sai Baba, M. [Resources Management Group (RMG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India)

    2015-01-15

    Highlights: • We study and compare Genetic Algorithms (GA) in the fuel bundle burnup optimization of an Indian Pressurized Heavy Water Reactor (PHWR) of 220 MWe. • Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are considered. • For the selected problem, Multi Objective GA performs better than Penalty Functions based GA. • In the present study, Multi Objective GA outperforms Penalty Functions based GA in convergence speed and better diversity in solutions. - Abstract: The work carried out as a part of application and comparison of GA techniques in nuclear reactor environment is presented in the study. The nuclear fuel management optimization problem selected for the study aims at arriving appropriate reference discharge burnup values for the two burnup zones of 220 MWe Pressurized Heavy Water Reactor (PHWR) core. Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are applied in this study. The study reveals, for the selected problem of PHWR fuel bundle burnup optimization, Multi Objective GA is more suitable than Penalty Functions based GA in the two aspects considered: by way of producing diverse feasible solutions and the convergence speed being better, i.e. it is capable of generating more number of feasible solutions, from earlier generations. It is observed that for the selected problem, the Multi Objective GA is 25.0% faster than Penalty Functions based GA with respect to CPU time, for generating 80% of the population with feasible solutions. When average computational time of fixed generations are considered, Penalty Functions based GA is 44.5% faster than Multi Objective GA. In the overall performance, the convergence speed of Multi Objective GA surpasses the computational time advantage of Penalty Functions based GA. The ability of Multi Objective GA in producing more diverse feasible solutions is a desired feature of the problem selected, that helps the

  7. Radio-toxicity of spent fuel of the advanced heavy water reactor.

    Science.gov (United States)

    Anand, S; Singh, K D S; Sharma, V K

    2010-01-01

    The Advanced Heavy Water Reactor (AHWR) is a new power reactor concept being developed at Bhabha Atomic Research Centre, Mumbai. The reactor retains many desirable features of the existing Pressurised Heavy Water Reactor (PHWR), while incorporating new, advanced safety features. The reactor aims to utilise the vast thorium resources available in India. The reactor core will use plutonium as the make-up fuel, while breeding (233)U in situ. On account of this unique combination of fuel materials, the operational characteristics of the fuel as determined by its radioactivity, decay heat and radio-toxicity are being viewed with great interest. Radio-toxicity of the spent fuel is a measure of potential radiological hazard to the members of the public and also important from the ecological point of view. The radio-toxicity of the AHWR fuel is extremely high to start with, being approximately 10(4) times that of the fresh natural U fuel used in a PHWR, and continues to remain relatively high during operation and subsequent cooling. A unique feature of this fuel is the peak observed in its radio-toxicity at approximately 10(5) y of decay cooling. The delayed increase in fuel toxicity has been traced primarily to a build-up of (229)Th, (230)Th and (226)Ra. This phenomenon has been observed earlier for thorium-based fuels and is confirmed for the AHWR fuel. This paper presents radio-toxicity data for AHWR spent fuel up to a period of 10(6) y and the results are compared with the radio-toxicity of PHWR.

  8. Microencapsulated Aliivibrio fischeri in Alginate Microspheres for Monitoring Heavy Metal Toxicity in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Dedi Futra

    2014-12-01

    Full Text Available In this article a luminescence fiber optic biosensor for the microdetection of heavy metal toxicity in waters based on the marine bacterium Aliivibrio fischeri (A. fischeri encapsulated in alginate microspheres is described. Cu(II, Cd(II, Pb(II, Zn(II, Cr(VI, Co(II, Ni(II, Ag(I and Fe(II were selected as sample toxic heavy metal ions for evaluation of the performance of this toxicity microbiosensor. The loss of bioluminescence response from immobilized A. fischeri bacterial cells corresponds to changes in the toxicity levels. The inhibition of the luminescent biosensor response collected at excitation and emission wavelengths of 287 ± 2 nm and 487 ± 2 nm, respectively, was found to be reproducible and repeatable within the relative standard deviation (RSD range of 2.4–5.7% (n = 8. The toxicity biosensor based on alginate micropsheres exhibited a lower limit of detection (LOD for Cu(II (6.40 μg/L, Cd(II (1.56 μg/L, Pb(II (47 μg/L, Ag(I (18 μg/L than Zn(II (320 μg/L, Cr(VI (1,000 μg/L, Co(II (1700 μg/L, Ni(II (2800 μg/L, and Fe(III (3100 μg/L. Such LOD values are lower when compared with other previous reported whole cell toxicity biosensors using agar gel, agarose gel and cellulose membrane biomatrices used for the immobilization of bacterial cells. The A. fischeri bacteria microencapsulated in alginate biopolymer could maintain their metabolic activity for a prolonged period of up to six weeks without any noticeable changes in the bioluminescence response. The bioluminescent biosensor could also be used for the determination of antagonistic toxicity levels for toxicant mixtures. A comparison of the results obtained by atomic absorption spectroscopy (AAS and using the proposed luminescent A. fischeri-based biosensor suggests that the optical toxicity biosensor can be used for quantitative microdetermination of heavy metal toxicity in environmental water samples.

  9. Microencapsulated Aliivibrio fischeri in alginate microspheres for monitoring heavy metal toxicity in environmental waters.

    Science.gov (United States)

    Futra, Dedi; Heng, Lee Yook; Surif, Salmijah; Ahmad, Asmat; Ling, Tan Ling

    2014-12-05

    In this article a luminescence fiber optic biosensor for the microdetection of heavy metal toxicity in waters based on the marine bacterium Aliivibrio fischeri (A. fischeri) encapsulated in alginate microspheres is described. Cu(II), Cd(II), Pb(II), Zn(II), Cr(VI), Co(II), Ni(II), Ag(I) and Fe(II) were selected as sample toxic heavy metal ions for evaluation of the performance of this toxicity microbiosensor. The loss of bioluminescence response from immobilized A. fischeri bacterial cells corresponds to changes in the toxicity levels. The inhibition of the luminescent biosensor response collected at excitation and emission wavelengths of 287 ± 2 nm and 487 ± 2 nm, respectively, was found to be reproducible and repeatable within the relative standard deviation (RSD) range of 2.4-5.7% (n = 8). The toxicity biosensor based on alginate micropsheres exhibited a lower limit of detection (LOD) for Cu(II) (6.40 μg/L), Cd(II) (1.56 μg/L), Pb(II) (47 μg/L), Ag(I) (18 μg/L) than Zn(II) (320 μg/L), Cr(VI) (1,000 μg/L), Co(II) (1700 μg/L), Ni(II) (2800 μg/L), and Fe(III) (3100 μg/L). Such LOD values are lower when compared with other previous reported whole cell toxicity biosensors using agar gel, agarose gel and cellulose membrane biomatrices used for the immobilization of bacterial cells. The A. fischeri bacteria microencapsulated in alginate biopolymer could maintain their metabolic activity for a prolonged period of up to six weeks without any noticeable changes in the bioluminescence response. The bioluminescent biosensor could also be used for the determination of antagonistic toxicity levels for toxicant mixtures. A comparison of the results obtained by atomic absorption spectroscopy (AAS) and using the proposed luminescent A. fischeri-based biosensor suggests that the optical toxicity biosensor can be used for quantitative microdetermination of heavy metal toxicity in environmental water samples.

  10. Bio-clarification of water from heavy metals and microbial effluence using fungal chitosan.

    Science.gov (United States)

    Tayel, Ahmed A; Gharieb, Mohamed M; Zaki, Hanaa R; Elguindy, Nihal M

    2016-02-01

    Water pollution is among the most hazardous problems that threaten human health worldwide. Chitosan is a marvelous bioactive polymer that could be produced from fungal mycelia. This study was conducted to produce chitosan from Cunninghamella elegans and to use it for water pollutants elimination, e.g. heavy metals and waterborne microorganisms, and to investigate its antibacterial mode of action against Escherichia coli. The produced fungal chitosan had a deacetylation degree of 81%, a molecular weight of 92.73 kDa and a matched FT-IR spectrum with standard shrimp chitosan. Fungal chitosan exhibited remarkable antimicrobial activity against E. coli, Staphylococcus aureus and Candida albicans. Chitosan was proved as an effective metal adsorbent, toward the examined metal ions, Cu2+, Zn2+ and Pb2+, and its adsorption capacity greatly increased with the increasing of metal concentration, especially for Cu and Zn. The scanning electron micrographs, of treated E. coli cells with fungal chitosan, indicated that the cells began to lyse and combine after 3h of exposure and chitosan particles attached to the combined cells and, after 12 h from exposure, the entire bacterial cell walls were fully disrupted and lysed. Therefore, fungal chitosan could be recommended, as a bioactive, renewable, ecofriendly and cost effective material, for overcoming water pollution problems, from chemical and microbial origins. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Health risk assessment of heavy metals and bacterial contamination in drinking water sources: a case study of Malakand Agency, Pakistan.

    Science.gov (United States)

    Nawab, Javed; Khan, Sardar; Ali, Sharafat; Sher, Hassan; Rahman, Ziaur; Khan, Kifayatullah; Tang, Jianfeng; Ahmad, Aziz

    2016-05-01

    Human beings are frequently exposed to pathogens and heavy metals through ingestion of contaminated drinking water throughout the world particularly in developing countries. The present study aimed to assess the quality of water used for drinking purposes in Malakand Agency, Pakistan. Water samples were collected from different sources (dug wells, bore wells, tube wells, springs, and hand pumps) and analyzed for different physico-chemical parameters and bacterial pathogens (fecal coliform bacteria) using standard methods, while heavy metals were analyzed using atomic absorption spectrophotometry (AAS-PEA-700). In the study area, 70 % of water sources were contaminated with F. coliform representing high bacterial contamination. The heavy metals, such as Cd (29 and 8 %), Ni (16 and 78 %), and Cr (7 %), exceeded their respective safe limits of WHO (2006) and Pak-EPA (2008), respectively, in water sources, while Pb (9 %) only exceeded from WHO safe limit. The risk assessment tools such as daily intake of metals (DIMs) and health risk indexes (HRIs) were used for health risk estimation and were observed in the order of Ni > Cr > Mn > Pb > Cd and Cd > Ni > Pb > Mn > Cr, respectively. The HRI values of heavy metals for both children and adults were <1, showing lack of potential health risk to the local inhabitants of the study area.

  12. Seasonal transfer of oxygen isotopes from precipitation and soil to the tree ring: source water versus needle water enrichment

    National Research Council Canada - National Science Library

    Treydte, Kerstin; Boda, Sonja; Graf Pannatier, Elisabeth; Fonti, Patrick; Frank, David; Ullrich, Bastian; Saurer, Matthias; Siegwolf, Rolf; Battipaglia, Giovanna; Werner, Willy; Gessler, Arthur

    2014-01-01

    ... to the tree rings of Larix decidua at two alpine sites in the Lötschental (Switzerland). Weekly resolved δ 18 O records of precipitation, soil water, xylem and needle water, phloem organic matter and tree rings were developed...

  13. Comparison of zinc reduction with platinum reduction for analysis of deuterium-enriched water samples for the doubly labeled water technique.

    Science.gov (United States)

    Herd, S L; Vaughn, W H; Goran, M I

    2000-07-01

    Isotope ratio mass spectrometry of hydrogen and oxygen is frequently used to determine total energy expenditure (TEE) using doubly labeled water. Conventionally, hydrogen isotope ratio is determined in hydrogen gas generated from water samples using zinc reduction. We compare this with a new automated platinum method to determine the ratios of hydrogen isotopes in deuterium-enriched water samples. The platinum method of sample preparation was compared with the zinc method in three ways: analytical variation in deuterium enrichment (within sample; n = 51), analytical variation in TEE estimates (within sample set; n = 10), and level of agreement of TEE estimates between both methods (n = 14). For the zinc method, the standard deviation for multiple sets of triplicate 2H2O sample analysis was +/-4.36 per thousand and +/-2.07 per thousand for platinum. The correlation between TEE estimates when sample sets were analyzed in duplicate was r = 0.89 for zinc and r = 0.83 for platinum. The intercept and slope of the regression line were significantly different from the line of identity for duplicate TEE estimates by zinc but were not different from the line of identity for platinum. After correction for the intra-assay variation of each method, the correlation between zinc and platinum for TEE was 0.77, and the intercept, but not the slope, of the regression was significantly different from the line of identity. The mean difference between the zinc method and the platinum method was 56 kcal/day, and the 95% confidence interval was -438 to 550 kcal/day. These data suggest that the platinum method is at least as reliable as the zinc method as a sample preparation technique for isotope ratio mass spectrometry of deuterium-enriched water samples. The platinum method is also less costly and less labor-intensive than the zinc method.

  14. Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters

    Science.gov (United States)

    Porter, S.D.; Mueller, D.K.; Spahr, N.E.; Munn, M.D.; Dubrovsky, N.M.

    2008-01-01

    1. Algal-community metrics were calculated for periphyton samples collected from 976 streams and rivers by the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Programme during 1993–2001 to evaluate national and regional relations with water chemistry and to compare whether algal-metric values differ significantly among undeveloped and developed land-use classifications.

  15. Intensity of methane seepage reflected by relative enrichment of heavy magnesium isotopes in authigenic carbonates: A case study from the South China Sea

    Science.gov (United States)

    Lu, Yang; Liu, Yufei; Sun, Xiaoming; Lin, Zhiyong; Xu, Li; Lu, Hongfeng; Hao, Xinrong; Peckmann, Jörn

    2017-11-01

    Changing conditions including steep redox gradients result in different Ca-Mg-carbonates forming at methane seeps as a consequence of sulfate-driven anaerobic oxidation of methane (SD-AOM). Since Mg2+ is one of the main cations in Ca-Mg-carbonates, Mg isotope composition may reflect the mode of mineral authigenesis at seeps. Seep carbonates were collected from the Shenhu area and the Southwest (SW) Taiwan basin in the South China Sea. The carbonate phases in Shenhu samples are dolomite accompanied by accessory Mg-calcite, while SW Taiwan samples consist of Mg-calcite and dolomite. Correspondingly, Shenhu carbonates show systematically higher Mg/Ca ratios. Low δ13C values of seep carbonates confirm their derivation from the oxidation of methane, δ18O values reflect formation in equilibrium with coeval seawater. The δ26Mg value of a reference sample of biodetrital carbonate (-4.28‰) is lower than those of seep carbonates (-3.25 to -2.95‰). Since only little variability of δ26Mg values of pore waters is expected based on previous work, differences in the δ26Mg values of seep carbonates were apparently caused by changing degrees of isotopic fractionation during precipitation. Trends between δ26Mg values and Mg/Ca ratios and between δ26Mg and δ13C values suggest that Mg isotope fractionation was controlled by a kinetic mechanism affecting the incorporation of Mg2+ ions into the carbonate lattice in the course of SD-AOM. By consuming sulfate and by producing sulfide, SD-AOM reduces the energy differences for the dehydration of ions of light and heavy Mg isotopes, lowering isotope fractionation. Additionally, the two trends have been found to be steeper for Shenhu samples, suggesting more pronounced SD-AOM in the Shenhu area. Our study indicates that Mg isotope composition of methane-derived carbonates is affected by the process that drives carbonate precipitation - SD-AOM. Future work is required to confirm the utility of Mg isotopes as a new proxy for this

  16. Classification of heavy metal ions present in multi-frequency multi-electrode potable water data using evolutionary algorithm

    Science.gov (United States)

    Karkra, Rashmi; Kumar, Prashant; Bansod, Baban K. S.; Bagchi, Sudeshna; Sharma, Pooja; Krishna, C. Rama

    2017-11-01

    Access to potable water for the common people is one of the most challenging tasks in the present era. Contamination of drinking water has become a serious problem due to various anthropogenic and geogenic events. The paper demonstrates the application of evolutionary algorithms, viz., particle swan optimization and genetic algorithm to 24 water samples containing eight different heavy metal ions (Cd, Cu, Co, Pb, Zn, Ar, Cr and Ni) for the optimal estimation of electrode and frequency to classify the heavy metal ions. The work has been carried out on multi-variate data, viz., single electrode multi-frequency, single frequency multi-electrode and multi-frequency multi-electrode water samples. The electrodes used are platinum, gold, silver nanoparticles and glassy carbon electrodes. Various hazardous metal ions present in the water samples have been optimally classified and validated by the application of Davis Bouldin index. Such studies are useful in the segregation of hazardous heavy metal ions found in water resources, thereby quantifying the degree of water quality.

  17. The Prospective Toxic Effects of Some Heavy Metals Overload in Surface Drinking Water of Dakahlia Governorate, Egypt

    Directory of Open Access Journals (Sweden)

    RA Mandour

    2011-09-01

    Full Text Available Background: The concentration of heavy metals in drinking water is very important. Objectives: To to evaluate the chemistry of some heavy metals in surface drinking water of Dakahlia Governorate, Egypt. Methods: 51 surface drinking water samples were collected from the main surface water stations and compact units in October 2009 and analyzed chemically. 26 water samples were analyzed by atomic absorption spectrophotometer for iron, manganese, lead, nickel, chromium, zinc, copper, cobalt, aluminum, and cadmium concentrations. Results: Aluminum concentration was slightly high in water sample of Bosat network. Cadmium concentration in samples of up-streams of shark and Mit-Khamis stations, networks of Mit-Antar, Demera, Bosat, Bilqas, El-satamony, El-Gamalia, Mit-asim and Bilqas station exceeded the permissible limits of Egyptian Ministry of Health (EMH, 2007 and World Health Organization (WHO, 2008. The nickel concentration in the network samples taken from Shoha, Bosat and El-Gamalia as well as up-stream of Bosat station exceeded the permissible limits. Also, lead concentrations of the network samples of Shoha, Mit-Antar, Demera and Nabaru exceeded the permissible limits. Conclusion: Regular chemical analysis of surface drinking water is required. Since these heavy metals are most likely originate from steel, plastics and batteries industries working in the region, we believe that activities of these industries must be stopped or at least limited in urban zones.

  18. Heavy metal concentrations in marine green, brown, and red seaweeds from coastal waters of Yemen, the Gulf of Aden

    Science.gov (United States)

    Al-Shwafi, Nabil A.; Rushdi, Ahmed I.

    2008-08-01

    The purpose of this study was to investigate the concentration levels of heavy metals in different species of the main three marine algal divisions from the Gulf of Aden coastal waters, Yemen. The divisions included Chlorophyta—green plants ( Halimeda tuna, Rhizoclonium kochiamum, Caldophora koiei, Enteromorpha compressa, and Caulerpa racemosa species), Phaeophyta—brown seaweeds ( Padina boryana, Turbinaria elatensis, Sargassum binderi, Cystoseira myrica, and Sargassum boveanum species), and Rhodophyta—red seaweeds ( Hypnea cornuta, Champia parvula, Galaxaura marginate, Laurencia paniculata, Gracilaria foliifere, and species). The heavy metals, which included cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), Iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn), and vanadium (V) were measured by Atomic Absorption Spectrophotometer (AAs). The concentrations of heavy metals in all algal species are in the order of Fe >> Cu > Mn > Cr > Zn > Ni > Pb > Cd > V > Co. The results also showed that the uptake of heavy metals by different marine algal divisions was in the order of Chlorophyta > Phaeophyta > Rhodophyta. These heavy metals were several order of magnitude higher than the concentrations of the same metals in seawater. This indicates that marine alga progressively uptake heavy metals from seawater.

  19. An Experimental Investigation of the Process of Isotope Exchange that Takes Place when Heavy Water Is Exposed to the Atmosphere

    Science.gov (United States)

    Deeney, F. A.; O'Leary, J. P.

    2009-01-01

    We have used the recently developed method for rapid measurement of maximum density temperature to determine the rate at which hydrogen and deuterium isotope exchange takes place when a sample of heavy water is exposed to the atmosphere. We also provide a simple explanation for the observed linear rate of transition. (Contains 2 figures.)

  20. Sustainable sources of biomass for bioremediation of heavy metals in waste water derived from coal-fired power generation.

    Science.gov (United States)

    Saunders, Richard J; Paul, Nicholas A; Hu, Yi; de Nys, Rocky

    2012-01-01

    Biosorption of heavy metals using dried algal biomass has been extensively described but rarely implemented. We contend this is because available algal biomass is a valuable product with a ready market. Therefore, we considered an alternative and practical approach to algal bioremediation in which algae were cultured directly in the waste water stream. We cultured three species of algae with and without nutrient addition in water that was contaminated with heavy metals from an Ash Dam associated with coal-fired power generation and tested metal uptake and bioremediation potential. All species achieved high concentrations of heavy metals (to 8% dry mass). Two key elements, V and As, reached concentrations in the biomass of 1543 mg.kg(-1) DW and 137 mg.kg(-1) DW. Growth rates were reduced by more than half in neat Ash Dam water than when nutrients were supplied in excess. Growth rate and bioconcentration were positively correlated for most elements, but some elements (e.g. Cd, Zn) were concentrated more when growth rates were lower, indicating the potential to tailor bioremediation depending on the pollutant. The cosmopolitan nature of the macroalgae studied, and their ability to grow and concentrate a suite of heavy metals from industrial wastes, highlights a clear benefit in the practical application of waste water bioremediation.

  1. Graphite-moderated and heavy water-moderated spectral shift controlled reactors; Reactores de moderador solido controlados por desplazamiento espectral

    Energy Technology Data Exchange (ETDEWEB)

    Alcala Ruiz, F.

    1984-07-01

    It has been studied the physical mechanisms related with the spectral shift control method and their general positive effects on economical and non-proliferant aspects (extension of the fuel cycle length and low proliferation index). This methods has been extended to non-hydrogenous fuel cells of high moderator/fuel ratio: heavy water cells have been con- trolled by graphite rods graphite-moderated and gas-cooled cells have been controlled by berylium rods and graphite-moderated and water-cooled cells have been controlled by a changing mixture of heavy and light water. It has been carried out neutron and thermal analysis on a pre design of these types of fuel cells. We have studied its neutron optimization and their fuel cycles, temperature coefficients and proliferation indices. Finally, we have carried out a comparative analysis of the fuel cycles of conventionally controlled PWRs and graphite-moderated, water-cooled and spectral shift controlled reactors. (Author) 71 refs.

  2. Modeling the source contribution of heavy metals in surficial sediment and analysis of their historical changes in the vertical sediments of a drinking water reservoir

    Science.gov (United States)

    Wang, Guoqiang; A, Yinglan; Jiang, Hong; Fu, Qing; Zheng, Binghui

    2015-01-01

    Increasing water pollution in developing countries poses a significant threat to environmental health and human welfare. Understanding the spatial distribution and apportioning the sources of pollution are important for the efficient management of water resources. In this study, ten types of heavy metals were detected during 2010-2013 for all ambient samples and point sources samples. A pollution assessment based on the surficial sediment dataset by Enrichment Factor (EF) showed the surficial sediment was moderately contaminated. A comparison of the multivariate approach (principle components analysis/absolute principle component score, PCA/APCS) and the chemical mass balance model (CMB) shows that the identification of sources and calculation of source contribution based on the CMB were more objective and acceptable when source profiles were known and source composition was complex. The results of source apportionment for surficial heavy metals, both from PCA/APCS and CMB model, showed that the natural background (30%) was the most dominant contributor to the surficial heavy metals, followed by mining activities (29%). The contribution percentage of the natural background was negatively related to the degree of contamination. The peak concentrations of many heavy metals (Cu, Ba, Fe, As and Hg) were found in the middle layer of sediment, which is most likely due to the result of development of industry beginning in the 1970s. However, the highest concentration of Pb appeared in the surficial sediment layer, which was most likely due to the sharp increase in the traffic volume. The historical analysis of the sources based on the CMB showed that mining and the chemical industry are stable sources for all of the sections. The comparing of change rates of source contribution versus years indicated that the composition of the materials in estuary site (HF1) is sensitive to the input from the land, whereas center site (HF4) has a buffering effect on the materials from

  3. Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection.

    Science.gov (United States)

    Zoll, Joffrey; Bouitbir, Jamal; Sirvent, Pascal; Klein, Alexis; Charton, Antoine; Jimenez, Liliana; Péronnet, François R; Geny, Bernard; Richard, Ruddy

    2015-01-01

    It has been suggested that oxygen (O2) diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates), which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients. Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1) at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg), with glutamate-malate or N, N, N', N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD)-ascorbate (with antimycin A) as substrates; and 2) at increasing adenosine diphosphate (ADP) concentration with glutamate-malate as substrate. As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate-malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD-ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was significantly lower with both electron donors in water enriched in O2 by electrolysis. This was not associated with any increase in the sensitivity of mitochondria to ADP; no significant difference was observed for the Km ADP between the two waters. In this experiment, a higher affinity of the mitochondria for O2 was observed in water enriched in O2 by electrolysis than by injection. This observation is consistent with the hypothesis that O2 diffusion can be facilitated in water enriched in O2 by the electrolytic process.

  4. Simple approach for the preparation of 15-15N2-enriched water for nitrogen fixation assessments: Evaluation, application and recommendations

    Directory of Open Access Journals (Sweden)

    Isabell eKlawonn

    2015-08-01

    Full Text Available Recent findings revealed that the commonly used 15N2 tracer assay for the determination of dinitrogen (N2 fixation can underestimate the activity of aquatic N2-fixing organisms. Therefore, a modification to the method using pre-prepared 15-15N2-enriched water was proposed. Here, we present a rigorous assessment and outline a simple procedure for the preparation of 15-15N2-enriched water. We recommend to fill sterile-filtered water into serum bottles and to add 15-15N2 gas to the water in amounts exceeding the standard N2 solubility, followed by vigorous agitation (vortex mixing ≥5 min. Optionally, water can be degassed at low-pressure (≥950 mbar for ten minutes prior to the 15-15N2 gas addition to indirectly facilitate the 15-15N2 dissolution. This preparation of 15-15N2-enriched water can be done within one hour using standard laboratory equipment. The final 15N-atom% excess was 5% after replacing 2–5% of the incubation volume with 15-15N2-enriched water. Notably, the addition of 15-15N2-enriched water can alter levels of trace elements in the incubation water due to the contact of 15-15N2-enriched water with glass, plastic and rubber ware during its preparation. In our tests, levels of trace elements (Fe, P, Mn, Mo, Cu, Zn increased by up to 0.1 nmol L-1 in the final incubation volume, which may bias rate measurements in regions where N2 fixation is limited by trace elements. For these regions, we tested an alternative way to enrich water with 15-15N2. The 15-15N2 was injected as a bubble directly to the incubation water, followed by gentle shaking. Immediately thereafter, the bubble was replaced with water to stop the 15-15N2 equilibration. This method achieved a 15N-atom excess of 6.6±1.7% when adding 2 mL 15-15N2 per liter of incubation water. The herein presented methodological tests offer guidelines for the 15N2 tracer assay and thus, are crucial to circumvent methodological draw-backs for future N2 fixation assessments.

  5. TREATMENT OF HEAVY METALS FROM WATER BY ELECTRO-PHYTOREMEDIATION TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Harikumar Puthenveedu Sadasivan Pillai

    2017-09-01

    Full Text Available The performance of electrically stimulated phytoremediation in the removal of lead, cadmium and copper was assessed in this study. A combination of phyto and electro remediation was attempted in this study for the remediation of the metals from water. Three tanks were setup with different operating conditions for this experiment: control A (only phytoremediation system, control B (only electro remediation and treatment (combination of phyto and electro remediation. The electrically enhanced phytoremediation system and electro remediation system were operated 2h/day at voltages of 4V for 25 days continuously. In this experiment, the Eichhornia crassipes, an able phyto-remediator exhibited efficient and fast removal of heavy metals from synthetic solution in electro assisted phytoremediation system. The electrically enhanced phytoremediation using aluminum sheet electrodes showed better and effective removal of Cd, Pb and Cu than aluminum rod electrodes. A more favorable and moderate increase of pH was noticed in electrically stimulated phytoremediation system. Eichhornia crassipes has tremendous potential to reduce maximum amount of cadmium (within 15 days, lead (within 15 days and copper (within 10 days under electrically stimulated condition. Under electrified condition, maximum amount of Cd and Cu was accumulated in the aerial parts of Eichhornia crassipes but maximum concentration of Pb was attained by roots. This indicates the high heavy metal accumulation capacity of Eichhornia crassipes under electrified conditions. The results showed that 4V voltage is probably suitable to stimulate the Eichhornia crassipes to synthesize more chlorophyll and voltage can improve growth and ability to resist adverse circumstances by promoting chlorophyll synthesis. Eichhornia crassipes stimulated by an electric field has grown better and assimilated more metal. Bioconcentration factor (BCF an index of hyperaccumulation, indicates that electrically

  6. FT-IR Spectra of Antifreeze Glycoproteins in Heavy Water and D2O Ice.

    Science.gov (United States)

    Tsvetkova, N. M.; Crowe, J. H.; Feeney, R. H.; Fink, W. H.; Yeh, Yin

    2000-03-01

    This work presents FT-IR studies on the antifreeze glycoprotein (AFGP)/heavy water (D2O) mixtures during freezing and melting. AFGP in the blood serum of polar fish are known to prevent ice crystal growth by a non-colligative mechanism. There are 8 known fractions of AFGP (1 8) that range in molecular mass from 33.7 to 2.6 kD respectively, each composed of alanine-alanine-threonine repeats, with a disaccharide attached to the threonine residue. The smallest peptide (AFGP-8) is structurally different from fractions 1-5 in that it contains proline substituting for alanine in certain positions. Substantial linewidth change of the D20 bending mode (ca. 1210 cm-1) was measured with solutions containing fractions 2-5 during both freezing and thawing cycles, suggesting significant coupling between protein and water molecules. At the same time, the Amide I band between 1620 and 1675 cm-1 shows that 310 helix and random coils are the main conformations of fractions 2-5 and fraction 8 in the presence of ice. In liquid state, b-sheet dominates the secondary structure of AFGP 8, whereas b-sheet and random coil are the main conformations of AFGP 2-5. These results are discussed in terms of the ability of AFGP 2-5 to affect the surface states of ice.

  7. Hydrophilic silver nanoparticles with tunable optical properties: application for the detection of heavy metals in water

    Directory of Open Access Journals (Sweden)

    Paolo Prosposito

    2016-11-01

    Full Text Available Due their excellent chemo-physical properties and ability to exhibit surface plasmon resonance, silver nanoparticles (AgNPs have become a material of choice in various applications, such as nanosensors, electronic devices, nanobiotechnology and nanomedicine. In particular, from the environmental monitoring perspective, sensors based on silver nanoparticles are in great demand because of their antibacterial and inexpensive synthetic method. In the present study, we synthesized AgNPs in water phase using silver nitrate as precursor molecules, hydrophilic thiol (3-mercapto-1-propanesulfonic acid sodium salt, 3MPS and sodium borohydride as capping and reducing agents, respectively. The AgNPs were characterized using techniques such as surface plasmon resonance (SPR spectroscopy, dynamic light scattering (DLS, zeta potential (ζ-potential measurements and scanning tunneling microscopy (STM. Further, to demonstrate the environmental application of our AgNPs, we also applied them for heavy metal sensing by detecting visible color modification due to SPR spectral changes. We found that these negatively charged AgNPs show good response to nickel (II and presented good sensibility properties for the detection of low amount of ions in water in the working range of 1.0–0.1 ppm.

  8. A water quality management strategy for regionally protected water through health risk assessment and spatial distribution of heavy metal pollution in 3 marine reserves.

    Science.gov (United States)

    Zhang, Yinan; Chu, Chunli; Li, Tong; Xu, Shengguo; Liu, Lei; Ju, Meiting

    2017-12-01

    Severe water pollution and resource scarcity is a major problem in China, where it is necessary to establish water quality-oriented monitoring and intelligent watershed management. In this study, an effective watershed management method is explored, in which water quality is first assessed using the heavy metal pollution index and the human health risk index, and then by classifying the pollution and management grade based on cluster analysis and GIS visualization. Three marine reserves in Tianjin were selected and analyzed, namely the Tianjin Ancient Coastal Wetland National Nature Reserve (Qilihai Natural Reserve), the Tianjin DaShentang Oyster Reef National Marine Special Reserve (DaShentang Reserve), and the Tianjin Coastal Wetland National Marine Special Reserve (BinHai Wetland Reserve) which is under construction. The water quality and potential human health risks of 5 heavy metals (Pb, As, Cd, Hg, Cr) in the three reserves were assessed using the Nemerow index and USEPA methods. Moreover, ArcGIS10.2 software was used to visualize the heavy metal index and display their spatial distribution. Cluster analysis enabled classification of the heavy metals into 4 categories, which allowed for identification of the heavy metals whose pollution index and health risks were highest, and, thus, whose control in the reserve is a priority. Results indicate that heavy metal pollution exists in the Qilihai Natural Reserve and in the north and east of the DaShentang Reserve; furthermore, human health risks exist in the Qilihai Natural Reserve and in the BinHai Wetland Reserve. In each reserve, the main factor influencing the pollution and health risk were high concentrations of As and Pb that exceed the corresponding standards. Measures must be adopted to control and remediate the pollutants. Furthermore, to protect the marine reserves, management policies must be implemented to improve water quality, which is an urgent task for both local and national governments. Copyright

  9. Community differentiation and population enrichment of Sargasso Sea bacterioplankton in the euphotic zone of a mesoscale mode-water eddy.

    Science.gov (United States)

    Nelson, Craig E; Carlson, Craig A; Ewart, Courtney S; Halewood, Elisa R

    2014-03-01

    Eddies are mesoscale oceanographic features (∼ 200 km diameter) that can cause transient blooms of phytoplankton by shifting density isoclines in relation to light and nutrient resources. To better understand how bacterioplankton respond to eddies, we examined depth-resolved distributions of bacterial populations across an anticyclonic mode-water eddy in the Sargasso Sea. Previous work on this eddy has documented elevated phytoplankton productivity and diatom abundance within the eddy centre with coincident bacterial productivity and biomass maxima. We illustrate bacterial community shifts within the eddy centre, differentiating populations uplifted along isopycnals from those enriched or depleted at horizons of enhanced bacterial and primary productivity. Phylotypes belonging to the Roseobacter, OCS116 and marine Actinobacteria clades were enriched in the eddy core and were highly correlated with pigment-based indicators of diatom abundance, supporting developing hypotheses that members of these clades associate with phytoplankton blooms. Typical mesopelagic clades (SAR202, SAR324, SAR406 and SAR11 IIb) were uplifted within the eddy centre, increasing bacterial diversity in the lower euphotic zone. Typical surface oligotrophic clades (SAR116, OM75, Prochlorococcus and SAR11 Ia) were relatively depleted in the eddy centre. The biogeochemical context of a bloom-inducing eddy provides insight into the ecology of the diverse uncultured bacterioplankton dominating the oligotrophic oceans. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  10. Amelioration of cardio-renal injury with aging in dahl salt-sensitive rats by H2-enriched electrolyzed water

    Science.gov (United States)

    2013-01-01

    Abstract Recent studies have revealed the biological effects of H2 in suppressing organ injuries due to acute inflammation and oxidative stress. Dahl salt-sensitive (SS) rats naturally develop elevated blood pressure (BP) and kidney injury with aging. The present study examined the effect of long-term supplementation of H2 in drinking water on age-related changes. Four-week-old male Dahl SS rats were fed 3 types of water (n = 30 each) for up to 48 weeks: filtered water (FW), water with a high H2 content (492.5 ppb) obtained with water electrolysis (EW), or dehydrogenated EW (DW). Animals were subjected to histological analysis at 16, 24, and 48 weeks. The FW group showed progressive BP elevation and increases in albuminuria and cardiac remodeling during the course of treatment. Histologically, there were significant changes as a function of aging, i.e., glomerular sclerosis with tubulointerstitial fibrosis in the kidney, and increased cardiomyocyte diameter with interstitial fibrosis in the heart at 48 weeks. These changes were related to the enhanced inflammation and oxidative stress in the respective organs. However, there were no striking differences in BP among the groups, despite histological alterations in the EW group being significantly decreased when compared to FW and DW in both organs, with concurrently lower oxidative stress and inflammatory markers at 48 weeks. Conclusion Long-term ad libitum consumption of H2-enriched electrolyzed water can ameliorate the processes of kidney injury and cardiac remodeling with aging in Dahl SS rats by suppressing, at least partly, elevated inflammation and oxidative stress. PMID:24289332

  11. Numerical Simulation Study on Steam-Assisted Gravity Drainage Performance in a Heavy Oil Reservoir with a Bottom Water Zone

    Directory of Open Access Journals (Sweden)

    Jun Ni

    2017-12-01

    Full Text Available In the Pikes Peak oil field near Lloydminster, Canada, a significant amount of heavy oil reserves is located in reservoirs with a bottom water zone. The properties of the bottom water zone and the operation parameters significantly affect oil production performance via the steam-assisted gravity drainage (SAGD process. Thus, in order to develop this type of heavy oil resource, a full understanding of the effects of these properties is necessary. In this study, the numerical simulation approach was applied to study the effects of properties in the bottom water zone in the SAGD process, such as the initial gas oil ratio, the thickness of the reservoir, and oil saturation of the bottom water zone. In addition, some operation parameters were studied including the injection pressure, the SAGD well pair location, and five different well patterns: (1 two corner wells, (2 triple wells, (3 downhole water sink well, (4 vertical injectors with a horizontal producer, and (5 fishbone well. The numerical simulation results suggest that the properties of the bottom water zone affect production performance extremely. First, both positive and negative effects were observed when solution gas exists in the heavy oil. Second, a logarithmical relationship was investigated between the bottom water production ratio and the thickness of the bottom water zone. Third, a non-linear relation was obtained between the oil recovery factor and oil saturation in the bottom water zone, and a peak oil recovery was achieved at the oil saturation rate of 30% in the bottom water zone. Furthermore, the operation parameters affected the heavy oil production performance. Comparison of the well patterns showed that the two corner wells and the triple wells patterns obtained the highest oil recovery factors of 74.71% and 77.19%, respectively, which are almost twice the oil recovery factors gained in the conventional SAGD process (47.84%. This indicates that the optimized SAGD process

  12. Simultaneous removal of oil and grease, and heavy metals from artificial bilge water using electro-coagulation/flotation.

    Science.gov (United States)

    Rincón, Guillermo J; La Motta, Enrique J

    2014-11-01

    US and international regulations pertaining to the control of bilge water discharges from ships have concentrated their attention to the levels of oil and grease rather than to the heavy metal concentrations. The consensus is that any discharge of bilge water (and oily water emulsion within 12 nautical miles from the nearest land cannot exceed 15 parts per million (ppm). Since there is no specific regulation for metal pollutants under the bilge water section, reference standards regulating heavy metal concentrations are taken from the ambient water quality criteria to protect aquatic life. The research herein presented discusses electro-coagulation (EC) as a method to treat bilge water, with a focus on oily emulsions and heavy metals (copper, nickel and zinc) removal efficiency. Experiments were run using a continuous flow reactor, manufactured by Ecolotron, Inc., and a synthetic emulsion as artificial bilge water. The synthetic emulsion contained 5000 mg/L of oil and grease, 5 mg/L of copper, 1.5 mg/L of nickel, and 2.5 mg/l of zinc. The experimental results demonstrate that EC is very efficient in removing oil and grease. For oil and grease removal, the best treatment and cost efficiency was obtained when using a combination of carbon steel and aluminum electrodes, at a detention time less than one minute, a flow rate of 1 L/min and 0.6 A/cm(2) of current density. The final effluent oil and grease concentration, before filtration, was always less than 10 mg/L. For heavy metal removal, the combination of aluminum and carbon steel electrodes, flow rate of 1 L/min, effluent recycling, and 7.5 amps produced 99% zinc removal efficiency. Copper and nickel are harder to remove, and a removal efficiency of 70% was achieved. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Heavy metal contents in the sediments of astatic ponds: Influence of geomorphology, hydroperiod, water chemistry and vegetation.

    Science.gov (United States)

    Gołdyn, Bartłomiej; Chudzińska, Maria; Barałkiewicz, Danuta; Celewicz-Gołdyn, Sofia

    2015-08-01

    The contents of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) were analysed in the bottom sediments of 30 small, astatic ponds located in the agricultural landscape of Western Poland. The samples were collected from 118 stations located in patches of four vegetation types. Relationships between the contents of particular elements and four groups of factors (geomorphology, hydroperiod, water quality and vegetation) were tested using Redundancy Analysis (RDA). The most important factors influencing the heavy metal contents were the maximum depth and area of the pond, its hydroperiod, water pH and conductivity values. In general, low quantities of heavy metals were recorded in the sediments of kettle-like ponds (small but located in deep depressions) and high in water bodies of the shore-bursting type (large but shallow). Moreover, quantities of particular elements were influenced by the structure of the vegetation covering the pond. Based on the results, we show which types of astatic ponds are most exposed to contamination and suggest some conservation practices that may reduce the influx of heavy metals. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Health risk assessment of heavy metals and metalloid in drinking water from communities near gold mines in Tarkwa, Ghana.

    Science.gov (United States)

    Bortey-Sam, Nesta; Nakayama, Shouta M M; Ikenaka, Yoshinori; Akoto, Osei; Baidoo, Elvis; Mizukawa, Hazuki; Ishizuka, Mayumi

    2015-07-01

    Concentrations of heavy metals and metalloid in borehole drinking water from 18 communities in Tarkwa, Ghana, were measured to assess the health risk associated with its consumption. Mean concentrations of heavy metals (μg/L) exceeded recommended values in some communities. If we take into consideration the additive effect of heavy metals and metalloid, then oral hazard index (HI) results raise concerns about the noncarcinogenic adverse health effects of drinking groundwater in Huniso. According to the US Environmental Protection Agency's (USEPA) guidelines, HI values indicating noncarcinogenic health risk for adults and children in Huniso were 0.781 (low risk) and 1.08 (medium risk), respectively. The cancer risk due to cadmium (Cd) exposure in adults and children in the sampled communities was very low. However, the average risk values of arsenic (As) for adults and children through drinking borehole water in the communities indicated medium cancer risk, but high cancer risk in some communities such as Samahu and Mile 7. Based on the USEPA assessment, the average cancer risk values of As for adults (3.65E-05) and children (5.08E-05) indicated three (adults) and five (children) cases of neoplasm in a hundred thousand inhabitants. The results of this study showed that residents in Tarkwa who use and drink water from boreholes could be at serious risk from exposure to these heavy metals and metalloid.

  15. Conceptual design and economic analysis of a light water reactor fuel enricher/regenerator. FY 1978 year-end report

    Energy Technology Data Exchange (ETDEWEB)

    Grand, P; Kouts, H J; Powell, J R; Steinberg, M; Takahashi, H

    1979-05-01

    A study has been performed to evaluate the use of high-energy particle accelerators as nuclear fuel enrichers and nuclear fuel regenerators. This builds on ideas that have been current for many years. The new study has, however, explored some novel approaches that have not been examined before. A specific conceptual system chosen for more detailed study would stretch the energy available from natural uranium by a factor of about 3, reduce the separative work requirements by a factor of about 4, and reduce the volume of spent fuel to be stored by a factor of 2, compared to the current once-through light water reactor (LWR) fuel cycle. The concept avoids the need for chemical reprocessing of spent fuel, and would permit continued use of LWR's beyond the time when limitations on fuel resources might otherwise lead to their being phased out. This concept, which is called the Linear Accelerator Fuel Enricher/Regenerator, is therefore viewed as offering a practical means of stretching the use of the nuclear fuel resource in the framework of the existing light water reactor fuel cycle. This report describes and analyzes the concept referred to. An explanation of the principles underlying the concept is given. Particular attention is devoted to engineering feasibility, proliferation resistance, and economics. It is seen that the concept draws on only proven technology as regards bothaccelerator design and the fuel irradiation process, and is adapted to existing LWR designs with no change except in fuel-handling practices. A preliminary evaluation of radiation damage, coolant options, and power conversion systems is provided. Neutronic, thermal-hydraulic, and burnup calculations are presented. An analysis is made of fuel economy. Approximate costs of electric power produced using this concept are evaluated and discussed. Estimated development costs of commercialization are provided.

  16. Response of lettuce to Cd-enriched water and irrigation frequencies

    African Journals Online (AJOL)

    hope&shola

    , S. Amin1, M. Maftoun2, Y. Emam3 and M. Noshadi1. 1Department of Water Engineering, College of Agriculture, Shiraz University, Shiraz, Iran. 2Department of Soil Sciences, Shiraz University, Shiraz, Iran. 3Department of Agronomy, Shiraz ...

  17. Water mutagenic potential assessment on a semiarid aquatic ecosystem under influence of heavy metals and natural radioactivity using micronuclei test.

    Science.gov (United States)

    Chaves, Luiz Cláudio Cardozo; Navoni, Julio Alejandro; de Morais Ferreira, Douglisnilson; Batistuzzo de Medeiros, Silvia; Ferreira da Costa, Thomas; Petta, Reinaldo Antônio; Souza do Amaral, Viviane

    2016-04-01

    The contamination of water bodies by heavy metals and ionizing radiation is a critical environmental issue, which can affect water quality and, thus, human health. This study aimed to evaluate the water quality of the Boqueirão de Parelhas Dam in the Brazilian semiarid region. A 1-year study (2013-2014) was performed through the assessment of physicochemical parameters, heavy metal content, and radioactivity along with the mutagenicity potential of water using micronuclei test in Orechromis niloticus (in vivo) and the cytokinesis-block micronucleus (CBMN) assay in human lymphocytes (in vitro). A deterioration of water organoleptics characteristics by the presence of high levels of sulfate and total solids was observed. High concentrations of aluminum, nickel, silver, and lead along with the alpha particle content were higher than the limits suggested by the World Health Organization and Brazilian legislation for drinking water. An increase in the frequency of micronuclei and nuclear abnormalities was observed in both experimental models. The results obtained confirmed the mutagenic potential present in water samples. This study highlights that geogenic agents affect water quality becoming a human health concern to be taken into account due to the relevance that this water reservoir has in the region.

  18. Toxic diatoms and domoic acid in natural and iron enriched waters of the oceanic Pacific.

    Science.gov (United States)

    Silver, Mary W; Bargu, Sibel; Coale, Susan L; Benitez-Nelson, Claudia R; Garcia, Ana C; Roberts, Kathryn J; Sekula-Wood, Emily; Bruland, Kenneth W; Coale, Kenneth H

    2010-11-30

    Near-surface waters ranging from the Pacific subarctic (58°N) to the Southern Ocean (66°S) contain the neurotoxin domoic acid (DA), associated with the diatom Pseudo-nitzschia. Of the 35 stations sampled, including ones from historic iron fertilization experiments (SOFeX, IronEx II), we found Pseudo-nitzschia at 34 stations and DA measurable at 14 of the 26 stations analyzed for DA. Toxin ranged from 0.3 fg·cell(-1) to 2 pg·cell(-1), comparable with levels found in similar-sized cells from coastal waters. In the western subarctic, descent of intact Pseudo-nitzschia likely delivered significant amounts of toxin (up to 4 μg of DA·m(-2)·d(-1)) to underlying mesopelagic waters (150-500 m). By reexamining phytoplankton samples from SOFeX and IronEx II, we found substantial amounts of DA associated with Pseudo-nitzschia. Indeed, at SOFeX in the Antarctic Pacific, DA reached 220 ng·L(-1), levels at which animal mortalities have occurred on continental shelves. Iron ocean fertilization also occurs naturally and may have promoted blooms of these ubiquitous algae over previous glacial cycles during deposition of iron-rich aerosols. Thus, the neurotoxin DA occurs both in coastal and oceanic waters, and its concentration, associated with changes in Pseudo-nitzschia abundance, likely varies naturally with climate cycles, as well as with artificial iron fertilization. Given that iron fertilization in iron-depleted regions of the sea has been proposed to enhance phytoplankton growth and, thereby, both reduce atmospheric CO(2) and moderate ocean acidification in surface waters, consideration of the potentially serious ecosystem impacts associated with DA is prudent.

  19. Toxic diatoms and domoic acid in natural and iron enriched waters of the oceanic Pacific

    Science.gov (United States)

    Silver, Mary W.; Bargu, Sibel; Coale, Susan L.; Benitez-Nelson, Claudia R.; Garcia, Ana C.; Roberts, Kathryn J.; Sekula-Wood, Emily; Bruland, Kenneth W.; Coale, Kenneth H.

    2010-01-01

    Near-surface waters ranging from the Pacific subarctic (58°N) to the Southern Ocean (66°S) contain the neurotoxin domoic acid (DA), associated with the diatom Pseudo-nitzschia. Of the 35 stations sampled, including ones from historic iron fertilization experiments (SOFeX, IronEx II), we found Pseudo-nitzschia at 34 stations and DA measurable at 14 of the 26 stations analyzed for DA. Toxin ranged from 0.3 fg·cell−1 to 2 pg·cell−1, comparable with levels found in similar-sized cells from coastal waters. In the western subarctic, descent of intact Pseudo-nitzschia likely delivered significant amounts of toxin (up to 4 μg of DA·m−2·d−1) to underlying mesopelagic waters (150–500 m). By reexamining phytoplankton samples from SOFeX and IronEx II, we found substantial amounts of DA associated with Pseudo-nitzschia. Indeed, at SOFeX in the Antarctic Pacific, DA reached 220 ng·L−1, levels at which animal mortalities have occurred on continental shelves. Iron ocean fertilization also occurs naturally and may have promoted blooms of these ubiquitous algae over previous glacial cycles during deposition of iron-rich aerosols. Thus, the neurotoxin DA occurs both in coastal and oceanic waters, and its concentration, associated with changes in Pseudo-nitzschia abundance, likely varies naturally with climate cycles, as well as with artificial iron fertilization. Given that iron fertilization in iron-depleted regions of the sea has been proposed to enhance phytoplankton growth and, thereby, both reduce atmospheric CO2 and moderate ocean acidification in surface waters, consideration of the potentially serious ecosystem impacts associated with DA is prudent. PMID:21068374

  20. Effect of long-term application of treated sewage water on heavy metal accumulation in vegetables grown in northern India.

    Science.gov (United States)

    Ghosh, Amlan Kr; Bhatt, M A; Agrawal, H P

    2012-01-01

    Use of industrial and wastewater for irrigation is on the rise in India and other developing countries because of scarcity of good-quality irrigation water. Wastewaters contain plant nutrients that favour crop growth but leave a burden of heavy metals which can enter the food chain and is a cause of great concern. The present study was undertaken on the long-term impact of irrigation with treated sewage water for growing vegetables and the potential health risk associated with consumption of such vegetable. Treated sewage water (TSW), groundwater (GW), soil and plant samples were collected from peri urban vegetable growing areas of Northern India (Varanasi) and analysed to assess the long-term effect of irrigation with TSW on Cd, Cr, Ni and Pb build-up in soils and its subsequent transfer into commonly grown vegetable crops. Results indicate that TSW was richer in essential plant nutrients but contained Cd, Cr and Ni in amounts well above the permissible limits for its use as irrigation water. Long-term application of TSW resulted in significant build-up of total and DTPA extractable Cd, Cr, Ni and Pb over GW irrigated sites. TSW also resulted in slight lowering in pH, increase in organic carbon (1.6 g kg(-1)) and cation exchange capacity (5.2 cmol kg(-1)). The tissue metal concentration and relative efficiency of transfer of heavy metals from soil to plant (transfer factor) for various groups of vegetables were worked out. Radish, turnip and spinach were grouped as hyper accumulator of heavy metals whereas brinjal and cauliflower accumulated less heavy metals. Health risk assessment by consumption of vegetables grown with TSW indicated that all the vegetables were safe for human consumption. However, significant accumulation of these heavy metals in soil and plant needs to be monitored.

  1. Temperature effect on leaf water deuterium enrichment and isotopic fractionation during leaf lipid biosynthesis: results from controlled growth of C3 and C4 land plants.

    Science.gov (United States)

    Zhou, Youping; Grice, Kliti; Chikaraishi, Yoshito; Stuart-Williams, Hilary; Farquhar, Graham D; Ohkouchi, Naohiko

    2011-02-01

    The hydrogen isotopic ratios ((2)H/(1)H) of land plant leaf water and the carbon-bound hydrogen of leaf wax lipids are valuable indicators for climatic, physiological, metabolic and geochemical studies. Temperature will exert a profound effect on the stable isotopic composition of leaf water and leaf lipids as it directly influences the isotopic equilibrium (IE) during leaf water evaporation and cellular water dissociation. It is also expected to affect the kinetics of enzymes involved in lipid biosynthesis, and therefore the balance of hydrogen inputs along different biochemical routes. We conducted a controlled growth experiment to examine the effect of temperature on the stable hydrogen isotopic composition of leaf water and the biological and biochemical isotopic fractionations during lipid biosynthesis. We find that leaf water (2)H enrichment at 20°C is lower than that at 30°C. This is contrary to the expectation that at lower temperatures leaf water should be more enriched in (2)H due to a larger equilibrium isotope effect associated with evapotranspiration from the leaf if all other variables are held constant. A hypothesis is presented to explain the apparent discrepancy whereby lower temperature-induced down-regulation of available aquaporin water channels and/or partial closure of transmembrane water channel forces water flow to "detour" to a more convoluted apoplastic pathway, effectively increasing the length over which diffusion acts against advection as described by the Péclet effect (Farquhar and Lloyd, 1993) and decreasing the average leaf water enrichment. The impact of temperature on leaf water enrichment is not reflected in the biological isotopic fractionation or the biochemical isotopic fractionation during lipid biosynthesis. Neither the biological nor biochemical fractionations at 20°C are significantly different from that at 30°C, implying that temperature has a negligible effect on the isotopic fractionation during lipid biosynthesis

  2. In vitro modulation of inflammatory target gene expression by a polyphenol-enriched fraction of rose oil distillation waste water.

    Science.gov (United States)

    Wedler, Jonas; Weston, Anna; Rausenberger, Julia; Butterweck, Veronika

    2016-10-01

    Classical production of rose oil is based on water steam distillation from the flowers of Rosa damascena. During this process, large quantities of waste water accrue which are discharged to the environment, causing severe pollution of both, groundwater and surface water due to a high content of polyphenols. We recently developed a strategy to purify the waste water into a polyphenol-depleted and a polyphenol-enriched fraction RF20-(SP-207). RF20-(SP-207) and sub-fraction F(IV) significantly inhibited cell proliferation and migration of HaCaT cells. Since there is a close interplay between these actions and inflammatory processes, here we focused on the fractions' influence on pro-inflammatory biomarkers. HaCaT keratinocytes were treated with RF20-(SP-207), F(IV) (both at 50μg/mL) and ellagic acid (10μM) for 24h under TNF-α (20ng/mL) stimulated and non-stimulated conditions. Gene expression of IL-1β, IL-6, IL-8, RANTES and MCP-1 was analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and cellular protein secretion of IL-8, RANTES and MCP-1 was determined by ELISA based assays. RF20-(SP-207) and F(IV) significantly decreased the expression and cellular protein secretion of IL-1β, IL-6, IL-8, RANTES and MCP-1. The diminishing effects on inflammatory target gene expression were slightly less pronounced under TNF-α stimulated conditions. In conclusion, the recovered polyphenol fraction RF20-(SP-207) from rose oil distillation waste water markedly modified inflammatory target gene expression in vitro, and, therefore, could be further developed as alternative treatment of acute and chronic inflammation. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Pollution characteristics and ecological risk assessment of heavy metals in the surface sediments from a source water reservoir

    Directory of Open Access Journals (Sweden)

    Changming Yang

    2016-10-01

    Full Text Available Surface sediment samples were collected from a source water reservoir in Zhejiang Province, East of China to investigate pollution characteristics and potential ecological risk of heavy metals. The BCR sequential extraction method was used to determine the four chemical fractions of heavy metals such as acid soluble, easily reducible, easily oxidizable and residual fractions. The heavy metals pollution and potential ecological risk were evaluated systematically using geoaccumulation index (Igeo and Hakanson potential ecological risk index (H′. The results showed that the sampling sites from the estuaries of tributary flowing through downtowns and heavy industrial parks showed significantly (p < 0.05 higher average concentrations of heavy metals in the surface sediments, as compared to the other sampling sites. Chemical fractionation showed that Mn existed mainly in acid extractable fraction, Cu and Pb were mainly in reducible fraction, and As existed mainly in residual fraction in the surface sediments despite sampling sites. The sampling sites from the estuary of tributary flowing through downtown showed significantly (p < 0.05 higher proportions of acid extractable and reducible fractions than the other sampling sites, which would pose a potential toxic risk to aquatic organisms as well as a potential threat to drinking water safety. As, Pb, Ni and Cu were at relatively high potential ecological risk with high Igeo values for some sampling locations. Hakanson potential ecological risk index (H′ showed the surface sediments from the tributary estuaries with high population density and rapid industrial development showed significantly (p < 0.05 higher heavy metal pollution levels and potential ecological risk in the surface sediments, as compared to the other sampling sites.

  4. Design of PIλDμ controller for global power control of Pressurized Heavy Water Reactor.

    Science.gov (United States)

    Bongulwar, M R; Patre, B M

    2017-07-01

    In this paper, a robust stabilizing controller design method is presented for global power control of a Pressurized Heavy Water Reactor (PHWR) under step-back condition scheme using a Fractional Order Proportional Integral Derivative (PIλDμ) controller resulting into robust performance. The method is applicable to design a controller for One Non Integer Order Plus Time Delay (NIOPTD-I) plant which satisfies design specifications such as phase margin and gain crossover frequency. Stability boundary locus method is used in (Kp, Ki, Kd) parameter space for NIOPTD-I plants to obtain stability region. The robust performance is obtained by satisfying flat phase condition at gain crossover frequency where phase is almost constant for large span of frequencies. The simulation result of the proposed PIλDμ controller shows active step-back control to the insertion of the rod with no undershoot and with the robust performance, hence safe to the plant for gain variations from 500% lower side to 1000% upper side. The PIλDμ controller with a plant shows that 30% and 50% global power drop from initial 100% is achieved in a reasonable time without undershoot. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Calculation of heat capacities of light and heavy water by path-integral molecular dynamics.

    Science.gov (United States)

    Shiga, Motoyuki; Shinoda, Wataru

    2005-10-01

    As an application of atomistic simulation methods to heat capacities, path-integral molecular dynamics has been used to calculate the constant-volume heat capacities of light and heavy water in the gas, liquid, and solid phases. While the classical simulation based on conventional molecular dynamics has estimated the heat capacities too high, the quantum simulation based on path-integral molecular dynamics has given reasonable results based on the simple point-charge/flexible potential model. The calculated heat capacities (divided by the Boltzmann constant) in the quantum simulation are 3.1 in the vapor H2O at 300 K, 6.9 in the liquid H2O at 300 K, and 4.1 in the ice Ih H2O at 250 K, respectively, which are comparable to the experimental data of 3.04, 8.9, and 4.1, respectively. The quantum simulation also reproduces the isotope effect. The heat capacity in the liquid D2O has been calculated to be 10% higher than that of H2O, while it is 13% higher in the experiment. The results demonstrate that the path-integral simulation is a promising approach to quantitatively evaluate the heat capacities for molecular systems, taking account of quantum-mechanical vibrations as well as strongly anharmonic motions.

  6. Trace incorporation of heavy water reveals slow and heterogeneous pathogen growth rates in cystic fibrosis sputum

    Science.gov (United States)

    Kopf, Sebastian H.; Sessions, Alex L.; Cowley, Elise S.; Reyes, Carmen; Van Sambeek, Lindsey; Hu, Yang; Orphan, Victoria J.; Kato, Roberta; Newman, Dianne K.

    2016-01-01

    Effective treatment for chronic infections is undermined by a significant gap in understanding of the physiological state of pathogens at the site of infection. Chronic pulmonary infections are responsible for the morbidity and mortality of millions of immunocompromised individuals worldwide, yet drugs that are successful in laboratory culture are far less effective against pathogen populations persisting in vivo. Laboratory models, upon which preclinical development of new drugs is based, can only replicate host conditions when we understand the metabolic state of the pathogens and the degree of heterogeneity within the population. In this study, we measured the anabolic activity of the pathogen Staphylococcus aureus directly in the sputum of pediatric patients with cystic fibrosis (CF), by combining the high sensitivity of isotope ratio mass spectrometry with a heavy water labeling approach to capture the full range of in situ growth rates. Our results reveal S. aureus generation times with a median of 2.1 d, with extensive growth rate heterogeneity at the single-cell level. These growth rates are far below the detection limit of previous estimates of CF pathogen growth rates, and the rates are slowest in acutely sick patients undergoing pulmonary exacerbations; nevertheless, they are accessible to experimental replication within laboratory models. Treatment regimens that include specific antibiotics (vancomycin, piperacillin/tazobactam, tobramycin) further appear to correlate with slow growth of S. aureus on average, but follow-up longitudinal studies must be performed to determine whether this effect holds for individual patients.

  7. Nanofiber Ion-Exchange Membranes for the Rapid Uptake and Recovery of Heavy Metals from Water

    Directory of Open Access Journals (Sweden)

    Nithinart Chitpong

    2016-12-01

    Full Text Available An evaluation of the performance of polyelectrolyte-modified nanofiber membranes was undertaken to determine their efficacy in the rapid uptake and recovery of heavy metals from impaired waters. The membranes were prepared by grafting poly(acrylic acid (PAA and poly(itaconic acid (PIA to cellulose nanofiber mats. Performance measurements quantified the dynamic ion-exchange capacity for cadmium (Cd, productivity, and recovery of Cd(II from the membranes by regeneration. The dynamic binding capacities of Cd(II on both types of nanofiber membrane were independent of the linear flow velocity, with a residence time of as low as 2 s. Analysis of breakthrough curves indicated that the mass flow rate increased rapidly at constant applied pressure after membranes approached equilibrium load capacity for Cd(II, apparently due to a collapse of the polymer chains on the membrane surface, leading to an increased porosity. This mechanism is supported by hydrodynamic radius (Rh measurements for PAA and PIA obtained from dynamic light scattering, which show that Rh values decrease upon Cd(II binding. Volumetric productivity was high for the nanofiber membranes, and reached 0.55 mg Cd/g/min. The use of ethylenediaminetetraacetic acid as regeneration reagent was effective in fully recovering Cd(II from the membranes. Ion-exchange capacities were constant over five cycles of binding-regeneration.

  8. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  9. Nanofiber Ion-Exchange Membranes for the Rapid Uptake and Recovery of Heavy Metals from Water

    Science.gov (United States)

    Chitpong, Nithinart; Husson, Scott M.

    2016-01-01

    An evaluation of the performance of polyelectrolyte-modified nanofiber membranes was undertaken to determine their efficacy in the rapid uptake and recovery of heavy metals from impaired waters. The membranes were prepared by grafting poly(acrylic acid) (PAA) and poly(itaconic acid) (PIA) to cellulose nanofiber mats. Performance measurements quantified the dynamic ion-exchange capacity for cadmium (Cd), productivity, and recovery of Cd(II) from the membranes by regeneration. The dynamic binding capacities of Cd(II) on both types of nanofiber membrane were independent of the linear flow velocity, with a residence time of as low as 2 s. Analysis of breakthrough curves indicated that the mass flow rate increased rapidly at constant applied pressure after membranes approached equilibrium load capacity for Cd(II), apparently due to a collapse of the polymer chains on the membrane surface, leading to an increased porosity. This mechanism is supported by hydrodynamic radius (Rh) measurements for PAA and PIA obtained from dynamic light scattering, which show that Rh values decrease upon Cd(II) binding. Volumetric productivity was high for the nanofiber membranes, and reached 0.55 mg Cd/g/min. The use of ethylenediaminetetraacetic acid as regeneration reagent was effective in fully recovering Cd(II) from the membranes. Ion-exchange capacities were constant over five cycles of binding-regeneration. PMID:27999394

  10. Modelling non-steady-state isotope enrichment of leaf water in a gas-exchange cuvette environment.

    Science.gov (United States)

    Song, Xin; Simonin, Kevin A; Loucos, Karen E; Barbour, Margaret M

    2015-12-01

    The combined use of a gas-exchange system and laser-based isotope measurement is a tool of growing interest in plant ecophysiological studies, owing to its relevance for assessing isotopic variability in leaf water and/or transpiration under non-steady-state (NSS) conditions. However, the current Farquhar & Cernusak (F&C) NSS leaf water model, originally developed for open-field scenarios, is unsuited for use in a gas-exchange cuvette environment where isotope composition of water vapour (δv ) is intrinsically linked to that of transpiration (δE ). Here, we modified the F&C model to make it directly compatible with the δv -δE dynamic characteristic of a typical cuvette setting. The resultant new model suggests a role of 'net-flux' (rather than 'gross-flux' as suggested by the original F&C model)-based leaf water turnover rate in controlling the time constant (τ) for the approach to steady sate. The validity of the new model was subsequently confirmed in a cuvette experiment involving cotton leaves, for which we demonstrated close agreement between τ values predicted from the model and those measured from NSS variations in isotope enrichment of transpiration. Hence, we recommend that our new model be incorporated into future isotope studies involving a cuvette condition where the transpiration flux directly influences δv . There is an increasing popularity among plant ecophysiologists to use a gas-exchange system coupled to laser-based isotope measurement for investigating non-steady state (NSS) isotopic variability in leaf water (and/or transpiration); however, the current Farquhar & Cernusak (F&C) NSS leaf water model is unsuited for use in a gas-exchange cuvette environment due to its implicit assumption of isotope composition of water vapor (δv ) being constant and independent of that of transpiration (δE ). In the present study, we modified the F&C model to make it compatible with the dynamic relationship between δv and δE as is typically associated

  11. Heavy metal pollution in marine mollusks from the coastal waters of ...

    African Journals Online (AJOL)

    Studies of heavy metals in four marine mollusks, Thais haemastoma, T. nodosa, Nerita senegalensis and P. perna, have been conducted. This involved the assessment of levels of heavy metal pollution from point sources in the Korle lagoon and the determination of the extent to which these metals are transported by ...

  12. High-throughput simultaneous determination of plasma water deuterium and 18-oxygen enrichment using a high-temperature conversion elemental analyzer with isotope ratio mass spectrometry.

    Science.gov (United States)

    Richelle, M; Darimont, C; Piguet-Welsch, C; Fay, L B

    2004-01-01

    This paper presents a high-throughput method for the simultaneous determination of deuterium and oxygen-18 (18O) enrichment of water samples isolated from blood. This analytical method enables rapid and simple determination of these enrichments of microgram quantities of water. Water is converted into hydrogen and carbon monoxide gases by the use of a high-temperature conversion elemental analyzer (TC-EA), that are then transferred on-line into the isotope ratio mass spectrometer. Accuracy determined with the standard light Antartic precipitation (SLAP) and Greenland ice sheet precipitation (GISP) is reliable for deuterium and 18O enrichments. The range of linearity is from 0 up to 0.09 atom percent excess (APE, i.e. -78 up to 5725 delta per mil (dpm)) for deuterium enrichment and from 0 up to 0.17 APE (-11 up to 890 dpm) for 18O enrichment. Memory effects do exist but can be avoided by analyzing the biological samples in quintuplet. This method allows the determination of 1440 samples per week, i.e. 288 biological samples per week. Copyright 2004 John Wiley & Sons, Ltd.

  13. [Transportation and risk assessment of heavy metal pollution in water-soil from the Riparian Zone of Daye Lake, China].

    Science.gov (United States)

    Zhang, Jia-quan; Li, Xiu; Zhang, Quan-fa; Li, Qiong; Xiao, Wen-sheng; Wang, Yong-kui; Zhang, Jian-chun; Gai, Xi-guang

    2015-01-01

    Each 20 water samples and soil samples (0-10 cm, 10-20 cm) were collected from the riparian zone of Daye Lake in dry season during March 2013. Heavy metals (Cu, Ph, Cd, Zn) have been detected by flame atomic absorption spectrometric (FAAS). The results showed that the average concentrations of Cu, Pb, Cd, Zn in the water were 7.14, 25.94, 15.72 and 37.58 microg x L(-1), respectively. The concentration of Cu was higher than the five degree of the surface water environment quality standard. The average concentrations of Cu, Pb, Cd, Zn in soil(0-10 cm) were 108.38, 53.92, 3.55, 139.26 mg x kg(-1) in soil (10-20 cm) were 93.00, 51.72, 2.08, 171.00 mg x kg(-1), respectively. The Cd concentrations were higher than the three grade value of the national soil environment quality standard. The transportation of Pb from soil to water was relatively stable, and Zn was greatly influenced by soil property and the surrounding environment from soil to water. The transformation of heavy metal in west riparian zone was higher than that of east riparian zone. The potential environmental risk was relatively high. Cu, Pb, Cd, Zn were dominated by residue fraction of the modified BCR sequential extraction method. The overall migration order of heavy metal element was: Pb > Cu > Cd > Zn. There were stronger transformation and higher environmental pollution risk of Cu, Pb. The index of assessment and potential ecological risk coefficient indicated that heavy metal pollution in soil (0-10 cm) was higher than the soil (10-20 cm), Cd was particularly serious.

  14. Heavy metals in Yeniçağa Lake and its potential sources: soil, water, sediment, and plankton.

    Science.gov (United States)

    Saygı, Yasemin; Yiğit, Sibel Atasagun

    2012-03-01

    The distribution and accumulation of heavy metals (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sn, Ba, Pb) in the water, sediments, plankton of Yeniçağa Lake, and its potential sources (creeks, sewage, artesian well, soil) were investigated during 1-year study period as monthly or seasonally. Element analyses were performed by ICP-MS. Results showed that the trace and toxic elements (Al, As, Mn, Pb, Fe) concentration in lake water and/or its feeding sources were above the recommended water standards (WHO, EC, EPA, TS-266). It was found that the maximum accumulation of the heavy metals iron, aluminum, manganese, zinc, and barium in the sediment of Yeniçağa Lake. The accumulation order of trace metals were Fe > Al > Mn > Zn > Ba > Ni > Cr > As > Cu > Pb > Co > Mo > Sn > Cd in the lake, creeks sediment, and soil samples. The similar results suggest that the accumulation of heavy metals in the sediment is a natural process. Metals accumulated in the lake are naturally mixed from the soil. However, the presence of heavy metals in the analysis of artesian well water and sewage reveals that the transportation occurs also from the groundwater to the lake. The results obtained in plankton in Yeniçağa Lake showed that aluminum, iron, manganese, zinc, and barium were most accumulated elements in the plankton. The lower averages of lead prevalent in the water and sediment during some months were seen to have a significant mean accumulation in the plankton.

  15. Hydrochemical processes in mine waste deposits and drainage water - Heavy metal speciation, sorption and sedimentation processes

    Energy Technology Data Exchange (ETDEWEB)

    Loevgren, L.; Sjoeberg, S. [Umeaa Univ. (Sweden). Dept. of Inorganic Chemistry

    1997-12-31

    The aim of the present project has been to quantitatively describe hydrochemical processes relevant for the retention and mobility of heavy metals in mine waste deposits. The activities have been focused on the solubility and speciation of Pb(II), Cd(II), Cu(II), Zn(II), CR(VI) and As(III,V). Main attention has been paid to adsorption processes at the surfaces of iron (hydr)oxides (goethite, et-FeOOH). The main experimental methods for studying the adsorption reactions have been potentiometric titrations and batch adsorption experiments. Experimental data have been evaluated in terms of models for surface complexation equilibria, which can be used in hydrogeochemical model calculations of processes within the deposits as well as in the recipients of drainage water. Furthermore, in several cases the surface complexes formed have been characterized structurally by means of Fourier Transform-Infrared spectroscopy. In order to test the validity of the equilibrium models obtained at millimolar concentrations of both sorbate and sorbent a new method utilizing Anodic Stripping Voltammetry as an in situ probe in titrations has been developed within the project. A particular interest has been given to the influence of complexing inorganic and organic anions on the adsorption of the heavy metal ions. The presence of sulfate ions resulted in a moderate increased adsorption of Cu(II) and Pb(II) under acidic conditions, while the adsorption of Zn(II) remained uninfluenced. The increased adsorption could be explained by reduced electrostatic repulsion between positively charged surfaces and metal ions, and by formation of ternary surface complexes. Similar mechanisms could explain the data in the goethite-Me(II)- carboxylate systems. The organic acids study are: phthalic acid, trimellitic acid and pyromellitic acid, which are aromatic acids with two, three and four carboxylate groups, respectively. Before the experimental data in the organic containing systems could be

  16. Water radiolysis with heavy ions of energies up to 28 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Shinichi [Department of Quantum Engineering and Systems Science, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Katsumura, Yosuke [Department of Nuclear Engineering and Management, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)], E-mail: katsu@n.t.u-tokyo.ac.jp; Lin, Mingzhang [Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Naka, Ibaraki 319-1195 (Japan); Muroya, Yusa [Nuclear Professional School, School of Engineering, University of Tokyo, 2-22 Shirakata-shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Miyazaki, Toyoaki [Department of Quantum Engineering and Systems Science, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Murakami, Takeshi [Research Center of Charged Particle Therapy, National Institute of Radiological Science, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2008-04-15

    Water radiolysis has been investigated with heavy ions having energies up to 28 GeV provided from the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). Beams of {sup 4}He{sup 2+}, {sup 12}C{sup 6+}, {sup 20}Ne{sup 10+}, {sup 28}Si{sup 14+}, {sup 40}Ar{sup 18+} and {sup 56}Fe{sup 26+} with respective energies of 150, 400, 400, 490, 500 and 500 MeV/u corresponding LET values of 2.2, 13, 30, 54, 92 and 183 eV/nm, respectively, were taken for the irradiation. The LET changes in sample solutions can be neglected due to their high energies for the irradiation of 1-cm cells. Primary g values have been determined for three important products, hydrated electron (e{sup -}{sub aq}), hydroxyl radical (.OH), and hydrogen peroxide (H{sub 2}O{sub 2}) as track segment yields (differential yields) under the conditions of neutral pH. With increasing LET, the g values of e{sup -}{sub aq} and {sup .}OH decrease from 2.4 and 2.6 in {sup 4}He{sup 2+} radiolysis to 0.9 and 1.1 (100 eV){sup -1} in {sup 56}Fe{sup 26+} radiolysis, respectively. It was also found that the primary g value of e{sup -}{sub aq} is smaller than that of .OH for any type of ion beam. For the {sup 12}C{sup 6+} beam, other energies such as 290, 220, 135 MeV/u were taken for the irradiation to investigate the effects of type or atomic number of ions on the measured yields. Furthermore, effects of dissolved oxygen on enhancement of H{sub 2}O{sub 2} production have also been investigated with aerated NaNO{sub 3} solutions. The presence of dissolved oxygen caused 15-35% enhancement in H{sub 2}O{sub 2} yields for all beams. In addition, the results of the present work were compared with reported track segment yields.

  17. The evaluation and determination of heavy metals pollution in edible vegetables, water and soil in the south of Tehran province by GIS

    Directory of Open Access Journals (Sweden)

    Shirkhanloo Hamid

    2015-06-01

    Full Text Available In this study, heavy metals pollutions in waters, soils and vegetables were investigated from farms, near oil refinery in south of Tehran city, Iran (Shahre Ray. The most important heavy metals in Iranian oil are vanadium, cobalt, nickel, arsenic and mercury (V, Co, Ni, As, Hg. In this region, the concentration of heavy metals in soils, well waters and leafy edible vegetables were evaluated in ten different points of farms. Geographic information systems (GIS were used to estimate the levels of heavy metals concentration at unmeasured locations. After sample preparation, concentrations of heavy metals in vegetables, soils and waters were determined by atomic absorption spectrometry (AAS. Five different leafy edible vegetables from farms, i.e., Persian leek, dill, parsley, spinach and radish were sampled in spring, summer and autumn 2012. In vegetables and well water samples, the concentrations of V, Ni and Co were above the permissible limit of heavy metals as compared to WHO guidelines and the concentrations of these metals in agricultural soils were found to be lower in accordance to soil references. The industrial waste waters had high concentration of heavy metals in this area. In consequence, the results of this study indicate that industrial waste water can cause pollution in well waters and edible vegetables. So, this region is not suitable for cultivation and growing vegetables.

  18. Accumulation of heavy metals with water quality parameters in Kızılırmak River Basin (Delice River) in Turkey.

    Science.gov (United States)

    Akbulut, Nuray Emir; Tuncer, A Murat

    2011-02-01

    Kızılırmak River has been used as Ankara's drinking water source for approximately 1.5 years. Therefore, this region's water, sediment, and fish samples are measured for detecting the heavy metals. This is important for the current situation as well as the future in terms of potential impact. The amount of heavy metals in drinking water should be within the limited values; otherwise, the accumulation of heavy metals will cause many problems to living organisms. Especially high levels of arsenic, cadmium, nickel, mercury, etc. are very dangerous to freshwater ecosystems as for human if the water is being use as drinking water. In this study, water, sediment samples, muscle, and gills of three fish species (Capoeta tinca, Capoeta capoeta, Leuciscus cephalus) were analyzed for the presence of heavy metals such as (Al, Fe, As, Cd, Ni, Mn, Se, Si) to determine present accumulation levels and possible toxic effect. The accumulation pattern of heavy metals in the water, sediment, and fish tissue follows the sequence: Si>Fe>Al>Mn>As>Ni>Se>Cd, Fe>Al>Mn>Ni>As>Se>Cd, and Fe>Al>Mn>As>Ni>Si>Cd. In addition, the detected concentrations of heavy metals in the Kızılırmak and Delice Rivers are compared with other heavy metal studies in the other main rivers and lakes in Turkey.

  19. Comparative Assessment of Heavy Metals in Drinking Water Sources in Two Small-Scale Mining Communities in Northern Ghana.

    Science.gov (United States)

    Cobbina, Samuel J; Duwiejuah, Abudu B; Quansah, Reginald; Obiri, Samuel; Bakobie, Noel

    2015-08-28

    The study assessed levels of heavy metals in drinking water sources in two small-scale mining communities (Nangodi and Tinga) in northern Ghana. Seventy-two (72) water samples were collected from boreholes, hand dug wells, dug-out, and a stream in the two mining communities. The levels of mercury (Hg), arsenic (As), lead (Pb), zinc (Zn), and cadmium (Cd) were determined using an atomic absorption spectrophotometer (AAS). Mean levels (mg/l) of heavy metals in water samples from Nangodi and Tinga communities were 0.038 and 0.064 (Hg), 0.031 and 0.002 (As), 0.250 and 0.031 (Pb), 0.034 and 0.002 (Zn), and 0.534 and 0.023 (Cd), respectively, for each community. Generally, levels of Hg, As, Pb, Zn, and Cd in water from Nangodi exceeded the World Health Organisation (WHO) stipulated limits of 0.010 for Hg, As, and Pb, 3.0 for Zn and 0.003 for Cd for drinking water, and levels of Hg, Pb, and Cd recorded in Tinga, exceeded the stipulated WHO limits. Ingestion of water, containing elevated levels of Hg, As, and Cd by residents in these mining communities may pose significant health risks. Continuous monitoring of the quality of drinking water sources in these two communities is recommended.

  20. [Correlation between multiple antibiotic resistance and heavy-metal tolerance among some E.coli strains isolated from polluted waters].

    Science.gov (United States)

    Lazăr, Veronica; Cernat, Ramona; Balotescu, Carmen; Cotar, Ani; Coipan, Elena; Cojocaru, Cristina

    2002-01-01

    Self-transmissible plasmids conferring multiple antibiotic resistance are wide-spread in coliforms populations. In soil and water, multiple antibiotic resistance is clearly associated with resistance/tolerance to heavy-metals (Hg2+, Cu2+, Pb2+, Zn2+, Ca2+). For different genera the genes for heavy-metals resistance are often plasmid encoded. Since these genes are clustered on the same plasmids, heavy-metals and drugs are environmental factors which exert a selective pressure for the populations of these plasmid-harboring bacteria. The aim of this preliminary study was to find possible correlation between resistance genotype determined by genetic analysis and antibiotic and heavy-metal resistance patterns of 12 E. coli strains isolated from chronically polluted waters. Antimicrobial susceptibility testing was performed for ampicillin, tetracycline, gentamycin, kanamycin, chloramphenicol, ceftazidime and cefotaxime by standard disk diffusion Kirby-Bauer method following NCCLS recommendations. These antibiotics were chosen because of their wide-spread use and importance in the treatment of Gram-negative bacterial infections. MICs values of antibiotics and heavy-metals were determined by dilution method in Mueller-Hinton broth using an inoculum of about 1-2 x 10(8) CFU/ml. The concentration range for antimicrobials and heavy-metals salts (CuSO4, CdCl2, Co(NO3)2, Cr(NO3)3, HgCl2, NiCl2 and ZnSO4) was 0.06-64 [symbol: see text] g/ml, 0.5-256 [symbol: see text] g/ml respectively. Plasmid DNA was isolated from E. coli strains by an alkaline lysis. Genetic characterization was performed by agarose gel electrophoresis and spectrophotometric analysis. All strains are multiple antibiotic resistant, 16% of them being resistant to 3, 4 and 6 antibiotics, 32% to 5 and 8% to all 7 antibiotics, respectively. Multiple tolerance to high levels of Cd2+, Cu2+, Cr3+ and Ni2+ was common among multiple antibioresistant strains. Screening for plasmids relieved the presence of several

  1. Bioactive compounds and antioxidant properties of pseudocereals-enriched water biscuits and their in vitro digestates.

    Science.gov (United States)

    Hidalgo, Alyssa; Ferraretto, Anita; De Noni, Ivano; Bottani, Michela; Cattaneo, Stefano; Galli, Simone; Brandolini, Andrea

    2018-02-01

    Carotenoids, tocols, phenolic acids and antioxidant capacity were studied during in vitro digestion of water biscuits (WB) from bread wheat, einkorn and einkorn-pseudocereals. Antioxidant and cytotoxic activities of digestates were also measured using a 70% Caco2/30% HT-29 human intestinal co-culture layer. Antioxidant profiles differed among WB formulations. Only hydrophilic molecules were solubilised by gastric digestion. After intestinal digestion, 77% carotenoids and 67% tocols were released. Soluble-conjugated phenolic acids increased (30%) and insoluble-bound forms decreased (17%), suggesting partial conversion from bound to conjugated form. After intestinal digestion, antioxidant capacity increased regardless of type and amount of antioxidants in undigested or digested WB. All WB, especially those with quinoa flour, reduced the AAPH pro-oxidant capacity in co-culture cells. These results highlight the potential health benefits of underutilized crops and the need for in vitro or in vivo models to better address potential bioactivity at intestinal and target organs level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Heavy metals phyto-assessment in commonly grown vegetables: water spinach (I. aquatica) and okra (A. esculentus)

    OpenAIRE

    Ng, Chuck Chuan

    2016-01-01

    The growth response, metal tolerance and phytoaccumulation properties of water spinach (Ipomoea aquatica) and okra (Abelmoschus esculentus) were assessed under different contaminated spiked metals: control, 50 mg Pb/kg soil, 50 mg Zn/kg soil and 50 mg Cu/kg soil. The availability of Pb, Zn and Cu metals in both soil and plants were detected using flame atomic absorption spectrometry. The concentration and accumulation of heavy metals from soil to roots and shoots (edible parts) were evaluated...

  3. Removal of Heavy Metal Ions from Polluted Waters by Using of Low Cost Adsorbents: Review

    Directory of Open Access Journals (Sweden)

    M. Ghaedi

    2013-06-01

    Full Text Available Adsorption is a fundamental process in the physicochemical treatment of wastewaters which industries employ to reduce hazardous organic and inorganic wastes in effluents. In recent years the use of low-cost adsorbents has been widely investigated as a replacement for the currently costly methods of removing heavy metal ions from wastewater. It is well-known that cellulosic waste materials can be obtained and employed as cheap adsorbents and their performance to remove heavy metal ions can be affected upon chemical treatment. In this study, the use of some of low cost adsorbents for the removal of heavy metals from wastewater has been reviewed.

  4. Combined effects of CO2 enrichment, changes in diurnal light level and water stress on foliar metabolites of potato plants grown in naturally sunlit controlled environment chambers

    Science.gov (United States)

    Potato plants (Solanum tuberosum L. cv Kennebec) were grown in outdoor, naturally sunlit, soil-plant-atmosphere research (SPAR) chambers. Drought treatments were imposed at post-tuber initiation stage to assess water stress effects on leaf metabolites, and interactions with enriched CO2 concentrati...

  5. On-line trace enrichment of polar pesticides in environmental waters by reversed-phase liquid chromatography-diode array detection-particle beam mass spectrometry.

    NARCIS (Netherlands)

    Brinkman, U.A.T.; Marcé, R.M.; Prosen, H.; Crespo, C.; Calull, M.; Borrull, F.

    1995-01-01

    The determination of a group of pesticides by RPLC-diode array detection, coupled on-line to particle beam MS, is developed for the analysis of different environmental water. On-line trace enrichment of 100 ml of sample on a PLRP-S precolumn allows the determination of most pesticides at levels

  6. Contribution of soil, water and food consumption to metal exposure of children from geological enriched environments in the coastal zone of Lake Victoria, Kenya.

    NARCIS (Netherlands)

    Oyoo-Okoth, E.; Admiraal, W.; Osano, O.; Manguya-Lusega, D; Ngure, V.; Kraak, M.H.S.; Chepkirui-Boit, V.; Makwali, J.

    2013-01-01

    Geologically enriched environments may contain high concentrations of some metals. In areas where industrial exposures remain superficial, children may be exposed to these geological metals through soil, drinking water and consumption of food locally grown. The aim of this study was to assess the

  7. Survey of Heavy Metal Contamination in Water Sources in the Municipality of Torola, El Salvador, through In Situ Sorbent Extraction

    Directory of Open Access Journals (Sweden)

    Enriqueta Anticó

    2017-11-01

    Full Text Available The presence of heavy metals in water resources directly affects consumer health. The quality of surface water resources in Central America is usually low due to the presence of metals and other pollutants. The lack of analytical instrumentation to perform routine monitoring of water has encouraged the development of easy tools to facilitate the determination of heavy metals in waters in remote sites. In this study, we evaluated the use of different sorbents, such as Adsorbsia As600 (titanium dioxide, Iontosorb Oxin, 8-hydroxyquinoline bearing functional groups, and Duolite GT-73, with thiol functionality, for Cd, Ni, Cu, Zn, and Al extraction. It was found that both Adsorbsia As600 and Iontosorb Oxin allowed the adsorption of all metals, and the recovery was achieved using either HCl or ethylenediaminetetraacetic sodium salt (EDTA solutions. Hence, Adsorbsia As600 was employed for in situ sampling in the metal contamination evaluation of water samples (from 15 wells and nine storage tanks from the municipality of Torola, Mozarán, El Salvador. The developed procedure allowed all the metals in the samples to be detected, and Ni and Al were found to be above Salvadoran guidelines for drinking water quality.

  8. Spatial and Temporal Heavy Metal Distribution and Surface Water Characterization of Kanjli Wetland (a Ramsar site), India Using Different Indices.

    Science.gov (United States)

    Singh, Navdeep; Kaur, Manpreet; Kaur Katnoria, Jatinder

    2017-12-01

    Suitability of surface water of Kanjli wetland, Punjab (India) during the period of 2013-2015 was assessed for drinking, irrigation and aquatic life using a water quality index (WQI), heavy metal pollution index (HPI) and aquatic toxicity index (ATI). WQI was calculated using 14 physico-chemical parameters while HPI determination used nine heavy metals like As, Cd, Co, Cr, Cu, Fe, Mn, Pb and Zn. WQI revealed that Kanjli wetland contained medium quality water (irrigation and aquatic life). Cr, Cd and Co exceeded desirable limits of World Health Organization (WHO, Guidelines for drinking-water quality, World Health Organization, Geneva, 2011) and Indian drinking water standard (2012) during all the three seasons (monsoon, post monsoon and winter). HPI values from all sites exceeded critical pollution index value of 100 during monsoon season. Few sites were unsuitable for normal fish life as per ATI. The study recommends planned spatial, temporal and periodic monitoring of wetland using WQI and HPI to sustain good water quality (drinking, irrigation and aquatic life).

  9. Heavy Water Reduces GFP Expression in Prokaryotic Cell-Free Assays at the Translation Level While Stimulating Its Transcription

    Directory of Open Access Journals (Sweden)

    Luisa S. Hohlefelder

    2013-01-01

    Full Text Available The in vitro proliferation of prokaryotic and eukaryotic cells is remarkably hampered in the presence of heavy water (D2O. Impairment of gene expression at the transcription or translation level can be the base for this effect. However, insights into the underlying mechanisms are lacking. Here, we employ a cell-free expression system for the quantitative analysis of the effect of increasing percentages of D2O on the kinetics of in-vitro GFP expression. Experiments are designed to discriminate the rates of transcription, translation, and protein folding using pDNA and mRNA vectors, respectively. We find that D2O significantly stimulates GFP expression at the transcription level but acts as a suppressor at translation and maturation (folding in a linear dose-dependent manner. At a D2O concentration of 60%, the GFP expression rate was reduced to 40% of an undisturbed sample. We observed a similar inhibition of GFP expression by D2O in a recombinant Escherichia coli strain, although the inhibitory effect is less pronounced. These results demonstrate the suitability of cell-free systems for quantifying the impact of heavy water on gene expression and establish a platform to further assess the potential therapeutic use of heavy water as antiproliferative agent.

  10. RADIATION DOSE DUE TO RADON AND HEAVY METAL ANALYSIS IN DRINKING WATER SAMPLES OF JAMMU DISTRICT, JAMMU & KASHMIR, INDIA.

    Science.gov (United States)

    Kumar, A; Kaur, M; Sharma, S; Mehra, R; Sharma, D K; Mishra, R

    2016-10-01

    In the present investigation, radon concentration and heavy metal analysis were carried out in drinking water samples in Jammu district, Jammu & Kashmir, India. The radon concentration was measured by using RAD-7, portable alpha particle detector. The values of radon concentration in drinking water samples were also compared within the safe limit recommended by different health agencies. The total annual effective dose ranged from 53.04 to 197.29 µSv y-1 The annual effective dose from few locations from the studied area was found to be greater than the safe limit (100 µSv y-1) suggested by World Health Organisation (WHO) and EU Council. Heavy metal concentration was determined by atomic absorption spectrophotometer. A total of eight elements were analysed, viz. arsenic, mercury, zinc, iron, copper, chromium, manganese and cadmium. Heavy metals are considered to be the major pollutants of water sources. The results were compared with the limits of WHO, EU and Indian organisations. The trace metal analysis is not on the exceeding side of the permissible limit in all the samples. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Heavy metals relationship with water and size-fractionated sediments in rivers using canonical correlation analysis (CCA) case study, rivers of south western Caspian Sea.

    Science.gov (United States)

    Vosoogh, Ali; Saeedi, Mohsen; Lak, Raziyeh

    2016-11-01

    Some pollutants can qualitatively affect aquatic freshwater such as rivers, and heavy metals are one of the most important pollutants in aquatic fresh waters. Heavy metals can be found in the form of components dissolved in these waters or in compounds with suspended particles and surface sediments. It can be said that heavy metals are in equilibrium between water and sediment. In this study, the amount of heavy metals is determined in water and different sizes of sediment. To obtain the relationship between heavy metals in water and size-fractionated sediments, a canonical correlation analysis (CCA) was utilized in rivers of the southwestern Caspian Sea. In this research, a case study was carried out on 18 sampling stations in nine rivers. In the first step, the concentrations of heavy metals (Cu, Zn, Cr, Fe, Mn, Pb, Ni, and Cd) were determined in water and size-fractionated sediment samples. Water sampling sites were classified by hierarchical cluster analysis (HCA) utilizing squared Euclidean distance with Ward's method. In addition, for interpreting the obtained results and the relationships between the concentration of heavy metals in the tested river water and sample sediments, canonical correlation analysis (CCA) was utilized. The rivers were grouped into two classes (those having no pollution and those having low pollution) based on the HCA results obtained for river water samples. CCA results found numerous relationships between rivers in Iran's Guilan province and their size-fractionated sediments samples. The heavy metals of sediments with 0.038 to 0.125 mm size in diameter are slightly correlated with those of water samples.

  12. Easily Regenerated Readily Deployable Absorbent for Heavy Metal Removal from Contaminated Water

    National Research Council Canada - National Science Library

    Perry N Alagappan; Jessica Heimann; Lauren Morrow; Enrico Andreoli; Andrew R Barron

    2017-01-01

    ...) via the growth of multi walled carbon nanotubes (MWNTs) onto a quartz substrate. Subsequent epoxidation provides sufficient functionality to enable adsorbent of heavy metals (Cd2+, Co2+, Cu2+, Hg2+, Ni2+, and Pb2...

  13. Heavy metals in fishes from coastal waters of Cochin, southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, M.; Balachandran, K.K.; Sankaranarayanan, V.N.; Joseph, T.

    The concentration levels of copper, zinc, manganese and iron have been determined in marine fishes from Cochin area which is one of the major fishing zones along the west coast of India. The concentration of heavy metals varied from species...

  14. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    National Research Council Canada - National Science Library

    Pujol, Luca; Evrard, David; Groenen-Serrano, Karine; Freyssinier, Mathilde; Ruffien-Cizsak, Audrey; Gros, Pierre

    2014-01-01

    A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses...

  15. Concentration of selected heavy metals in water of the Juru River ...

    African Journals Online (AJOL)

    analytical grade HNO3). Heavy metal concentrations were determined using inductively couple plasma (ICP model Perkin elmer/elan 9000) following standard method procedures. For comparison purposes, the river was divided into three ...

  16. Concentrations, diffusive fluxes and toxicity of heavy metals in pore water of the Fuyang River, Haihe Basin.

    Science.gov (United States)

    Tang, Wenzhong; Duan, Shenghui; Shan, Baoqing; Zhang, Hong; Zhang, Wenqiang; Zhao, Yu; Zhang, Chao

    2016-05-01

    While the concentrations of heavy metals in pore water provide important information about their bioavailability, to date few studies have focused on this topic. In this study, pore water in river sediments collected from nine sampling sites (S1-S9) was examined to determine the concentrations, fluxes, and toxicity of heavy metals in the Fuyang River. The results showed that the average concentrations of Cr, Ni, Cu, As, Zn, and Pb in pore water were 17.06, 15.97, 20.93, 19.08, 43.72, and 0.56μgL(-1), respectively; these concentrations varied as the pore water depth increased. The diffusive fluxes of Cr, Ni, Cu, As, Zn, and Pb were in the following range: (-0.37) to 3.17, (-1.37) to 2.63, (-4.61) to 3.44, 0.17-6.02, (-180.26) to 7.51, and (-0.92) to (-0.29)μg(m(2)day)(-1), respectively. There was a potential risk of toxicity from Cu to aquatic organisms, as indicated by a value of the Interstitial Water Criteria Toxic Units that exceeded 1.0. Values of the Nemeraw Index were 2.06, 0.48, 0.11, 0.20, 1.11, 1.03, 0.99, 0.88, and 0.89 from S1 to S9, respectively. Only S1 was moderately polluted by heavy metals in pore water. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Precipitation of heavy metals in waste waters; Precipitacion de metales pesados en las aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Stutzel, K.; Peldszus, R.

    1997-06-01

    Heavy metals content in effluents is regulated due to their toxicity. To minimized them different precipitating agents are used. A comparison between some precipitating agents (the most common is H{sub 2}S) wit trimercapto-s-triazine (TMT 15) is shown. Solubility products of TMT 15 with divalent metals are very low: the precipitation with TMT 15 gives a heavy metal concentration in effluents below regulated levels. (Author)

  18. Evaluation of heavy metals in the tissues of different species of shrimps collected from coastal waters of Bushehr, Persian Gulf

    Directory of Open Access Journals (Sweden)

    Ali Movahed

    2013-06-01

    Full Text Available Background: The occumulation of heavy metals which are as the results of industrial, urban and agricultural sewages are usually resistant to chemical dissociation. They can easily contaminate aquatic animals especially shrimps which are one of the food chains of humans. The aim of this study was to evaluate the concentration of heavy metals in the tissues of different types of shrimps (wild and farmed in the sea waters of province of Bushehr (Persian Gulf. Material and Methods: Wild shrimps from different areas of the province and also three types of farmed shrimps including Ferropenaeus, penaeus semisulcatus and Litopenaeusvannamei were caught and collected. Then cleaned, washed, dried and made into powder and then made into ash in a furnace at 550 °C. Heavy metals including Pb, Cd, Hg, Cu, and Zn were measured by atomic absorption flame photometry. Results: The mean values of the concentration of the heavy metals including Pb, Cd, Zn, and Cu present in the wild shrimps were, 2.86, 9.53, 0.45, 1.36 ppm respectively. The amount of Hg found to be 2.8 ppb. Also the mean values of the concentration of the heavy metals in the farmed shrimps were measured as 3, 9.8, 0.42 and 1.37 ppm respectively and the amount of Hg was 2.7 ppb. There was no difference between the amount of heavy metals estimated in the tissues from wild shrimps and the farmed one. Conclusion: The results of this investigation showed that the concentration of heavy metals including Zn,Cu and Hg in both types of the shrimps were less than the amounts reported by WHO and so not risky for health. However the concentration of Pb and Cd in both types were more than the recommended consumption limit for the humans, and they can be considered as risk factors for many diseases. This suggests that attempts should be taken by the responsible authorities to prevent the contamination of sea waters.

  19. Distribution and Risk Assessment of Heavy Metals in Surface Water from Pristine Environments and Major Mining Areas in Ghana

    Directory of Open Access Journals (Sweden)

    George Yaw Hadzi

    2015-01-01

    Conclusions. The concentrations of heavy metals in the Nyam, Subri, Bonsa and Birim Rivers from the mining sites and the Atiwa Range, Oda, Ankasa and Bosomkese Rivers from the pristine sites were found to be either below or within the USEPA and WHO's recommended limits for surface water. The health risk assessment values for the hazard quotient for ingestion of water (HQing, dermal contact (HQderm and chronic daily intake (CDI indicated no adverse effects as a result of ingestion or dermal contact from the rivers. However, arsenic (As in both the pristine and mining sites and chromium (Cr in the pristine sites pose a carcinogenic threat to the local residents.

  20. Spatial distribution and transport of heavy metals in soil, ponded-surface water and grass in a pb-contaminated watershed as related to land-use practices.

    Science.gov (United States)

    Panichayapichet, P; Nitisoravut, S; Simachaya, W

    2007-12-01

    The aim of this study was to investigate the spatial distribution of heavy metal in soil and evaluate the dissolution of metal from soil to ponded-surface water, leaching through soil profiles and metal uptake in grass as related to different land-use practices. The data provided a scientific basis for best-management practices for land use in Khli Ti watershed. The watershed has a Pb-contamination problem from the previous operation of a Pb-ore concentrator and abandoned Zn-Pb mine. Sampling sites were selected from a land-use map, with land-use types falling into the following four categories: forest, agricultural land, residential area and road. Soil, ponded-surface water, grass samples and soil profiles were collected. The study related soil characteristics from different land-use practices and locations with observed metal concentrations in ponded-surface water and soil. High enrichment factors of Pb and As in soil were found. Partitioning coefficient, K(d) values were in the order: Cr > Pb > Ni > Cu > Cd > Zn. Soil disturbance from land-use activities including tillage and traffic increased leaching of trace metal from soils. Pb in soil was significantly taken up by grass even though the Transfer Factor, TF values were rather low. Agricultural activities in the watershed must be limited. Moreover, land encroachments in the upper and middle part of the watershed which have high potential of Pb must be strictly controlled in order to reduce the Pb contamination from non-point sources.

  1. Water-soluble organo-building blocks of aminoclay as a soil-flushing agent for heavy metal contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Chul [Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Eun Jung [Advanced Biomass R and D Center, KAIST, 291 Daehakno, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Ko, Dong Ah [Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Yang, Ji-Won, E-mail: jiwonyang@kaist.ac.kr [Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Advanced Biomass R and D Center, KAIST, 291 Daehakno, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2011-11-30

    Highlights: Black-Right-Pointing-Pointer Aminoclays have synthesized using centered metals with aminopropyl silane. Black-Right-Pointing-Pointer Developed aminoclay has unique nano-sized and water-soluble properties. Black-Right-Pointing-Pointer Aminoclay showed high heavy metal capacity with metal ions and its less toxicity. Black-Right-Pointing-Pointer Aminoclay could be used to remediate heavy metals from soils an alternative soil-flushing agent. - Abstract: We demonstrated that water-soluble aminopropyl magnesium functionalized phyllosilicate could be used as a soil-flushing agent for heavy metal contaminated soils. Soil flushing has been an attractive means to remediate heavy metal contamination because it is less disruptive to the soil environment after the treatment was performed. However, development of efficient and non-toxic soil-flushing agents is still required. We have synthesized aminoclays with three different central metal ions such as magnesium, aluminum, and ferric ions and investigated applicability of aminoclays as soil flushing agents. Among them, magnesium (Mg)-centered aminoclay showed the smallest size distribution and superior water solubility, up to 100 mg/mL. Mg aminoclay exhibited cadmium and lead binding capacity of 26.50 and 91.31 mg/g of Mg clay, respectively, at near neutral pH, but it showed negligible binding affinity to metals in acidic conditions. For soil flushing with Mg clay at neutral pH showed cadmium and lead were efficiently extracted from soils by Mg clay, suggesting strong binding ability of Mg clay with cadmium and lead. As the organic matter and clay compositions increased in the soil, the removal efficiency by Mg clay decreased and the operation time increased.

  2. The Development of Environmentally Friendly Technologies of Using Coals and Products of Their Enrichment in the Form of Coal Water Slurries

    Science.gov (United States)

    Murko, Vasily; Hamalainen, Veniamin

    2017-11-01

    The article presents the current state of the technology for production and combustion of fuel coal water slurries in Russia and foreign countries. Experimental and industrial facilities show the technological and economic efficiency of using this technology for disposal of wastes resulting after coal processing and enrichment. The feasibility studies of use of the technology at large Kuzbass thermal power stations are presented. The possibility of solving a serious environmental problem of reducing storage of the most toxic waste of coal enrichment in the location areas of coal washing plants and coal mining enterprises is demonstrated.

  3. Development of magnetic graphene @hydrophilic polydopamine for the enrichment and analysis of phthalates in environmental water samples.

    Science.gov (United States)

    Wang, Xianying; Song, Guoxin; Deng, Chunhui

    2015-01-01

    Magnetic graphene @hydrophilic polydopamine composites were successfully fabricated via a simple solvothermal reaction and self-polymerization of dopamine. Benefit from the excellent characteristics of strong magnetic responsivity, super-hydrophilicity and abundant π-electron system, the prepared material showed great potential as a magnetic solid phase extraction (MSPE) sorbent. In this work, six kinds of phthalates (PAEs) were selected as the target analytes to evaluate the extraction ability of the adsorbents combined with MSPE-GC-MS. And various extraction parameters were optimized by selecting the pH value of samples, the amount of sorbents, adsorption and desorption time, the type and volume of eluting solution. Meanwhile, the whole extraction process could be finished in 30 min. Under the optimized conditions, validations of the method were evaluated as well. And the results presented excellent linearity with a wide range of 50-20,000 μg/L (R(2)>0.9991). The detection of limits were in the range from 0.05-5 μg/L (S/N=3). Therefore, the novel magnetic graphene@polydopamine composites were successfully used as the sorbents for the enrichment and analysis of PAEs in real water samples. This proposed method provided a simple, efficient and sensitive approach for the determination of aromatic compounds in real environmental samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Selective trace enrichment of chlorotriazine pesticides from natural waters and sediment samples using terbuthylazine molecularly imprinted polymers

    Science.gov (United States)

    Ferrer, I.; Lanza, F.; Tolokan, A.; Horvath, V.; Sellergren, B.; Horvai, G.; Barcelo, D.

    2000-01-01

    Two molecularly imprinted polymers were synthesized using either dichloromethane or toluene as the porogen and terbuthylazine as the template and were used as solid-phase extraction cartridges for the enrichment of six chlorotriazines (deisopropylatrazine, deethylatrazine, simazine, atrazine, propazine, and terbuthylazine) in natural water and sediment samples. The extracted samples were analyzed by liquid chromatography/diode array detection (LC/DAD). Several washing solvents, as well as different volumes, were tested for their ability to remove the matrix components nonspecifically adsorbed on the sorbents. This cleanup step was shown to be of prime importance to the successful extraction of the pesticides from the aqueous samples. The optimal analytical conditions were obtained when the MIP imprinted using dichloromethane was the sorbent, 2 mL of dichloromethane was used in the washing step, and the preconcentrated analytes were eluted with 8 mL of methanol. The recoveries were higher than 80% for all the chlorotriazines except for propazine (53%) when 50- or 100-mL groundwater samples, spiked at 1 ??g/L level, were analyzed. The limits of detection varied from 0.05 to 0.2 ??g/L when preconcentrating a 100-mL groundwater sample. Natural sediment samples from the Ebre Delta area (Tarragona, Spain) containing atrazine and deethylatrazine were Soxhlet extracted and analyzed by the methodology developed in this work. No significant interferences from the sample matrix were noticed, thus indicating good selectivity of the MIP sorbents used.

  5. Toward a better δDalkanes paleoclimate proxy; Partitioning of seasonal water sources and xylem-leaf deuterium enrichment according to plant growth form and phenology

    Science.gov (United States)

    Wispelaere, Lien; Bodé, Samuel; Herve-Fernández, Pedro; Hemp, Andreas; Verschuren, Dirk; Boeckx, Pascal

    2016-04-01

    The DeepCHALLA consortium is preparing an ICDP (International Continental Drilling Program) deep-drilling project on Lake Challa, a crater lake near Mt. Kilimanjaro in equatorial East Africa, where the climate is tropical semi-arid climate and characterized by two distinct rainy seasons. The main objective of this project is to acquire high-resolution and accurately dated proxy data of continental climate and ecosystem change near the Equator over 250,000 years. One of the paleoclimate proxies to be used is the hydrogen-isotopic composition of sedimentary n-alkanes (δDalkanes) derived from fossil plant leaf wax. However, this requires a better understanding of seasonal variability in the isotopic composition of precipitation, and of the fractionation of its hydrogen during incorporation in the plant waxes. In addition, recent studies have described the existence of "two water worlds", resulting in an additional deviation of the isotopic composition of the water taken up by plants. In this study, we measured the δD and δ18O of local precipitation, lake water, and xylem and leaf water from different plant species, seasons and sites with varying distances to Lake Challa. We use these data to set up a local meteoric water line (LMWL), and to assess spatial and temporal patterns of water utilization by local plants. Our data show a seasonal change in water-isotope partitioning with plants tapping water from isotopically lighter water sources during the dry seasons, as indicated by more negative xylem δD values and higher offsets from precipitation (i.e. greater distances from the LMWL), therefore supporting the "two water worlds" hypothesis. Surprisingly, trees appear to preferentially exploit isotopically more enriched sources of soil water, suggesting shallower water sources, than shrubs. Plants located at the lake shore use a mixture of precipitation and lake water, reflected in enriched xylem δD values and in the intersection of 2H and 18O with the LMWL. Leaf-water

  6. No evidence of enhanced satiety following whey protein- or sucrose-enriched water beverages: a dose response trial in overweight women.

    Science.gov (United States)

    Wiessing, K R; Xin, L; Budgett, S C; Poppitt, S D

    2015-11-01

    To compare the effect of low-dose whey protein-enriched and sucrose-enriched water beverages on postprandial satiety and energy intake. Sixty overweight and obese women were given water-based protein and carbohydrate (CHO) beverages or placebo on six different occasions in a double-blind, randomised cross-over study. The beverages were 2 (178 kJ) and 4% (348 kJ) protein-enriched water (Clear Protein8855), 2 (157 kJ), 4 (314 kJ) and 10% (785 kJ) sucrose-enriched water, and a sweetened water control. Beverages were matched for volume, colour, flavour and sweetness. A standardised evening meal was provided before each study day and a standardised breakfast upon arrival at the clinic at 0900 hours. The beverage preload was given midmorning at 1100 hours, and an ad libitum outcome lunch meal at 1300 hours. Subjective appetitive responses were recorded through the day until 1500 hours using visual analogue scales. Fifty-five participants completed all six beverage conditions. Neither protein nor sucrose preloads decreased any of hunger, fullness, thoughts of food or satisfaction when compared with the sweetened water control beverage (all, P>0.05). There was also no significant effect on ad libitum energy or macronutrient intake at the outcome meal (P>0.05), with no compensation for the energy consumed within the preload beverages. There was no evidence of increased postprandial satiety or compensation for energy content at an outcome lunch meal when a water beverage was supplemented with up to 4% (w/w) whey protein or 10% (w/w) sucrose, in a group of overweight but unrestrained young and middle-aged women.

  7. Subcritical water treatment of explosive and heavy metals co-contaminated soil: Removal of the explosive, and immobilization and risk assessment of heavy metals.

    Science.gov (United States)

    Islam, Mohammad Nazrul; Jung, Ho-Young; Park, Jeong-Hun

    2015-11-01

    Co-contamination of explosives and heavy metals (HMs) in soil, particularly army shooting range soil, has received increasing environmental concern due to toxicity and risks to ecological systems. In this study, a subcritical water (SCW) extraction process was used to remediate the explosives-plus-HMs-co-contaminated soil. A quantitative evaluation of explosives in the treated soil, compared with untreated soil, was applied to assess explosive removal. The immobilization of HMs was assessed by toxicity characteristic leaching procedure tests, and by investigating the migration of HMs fractions. The environmental risk of HMs in the soil residue was assessed according to the risk assessment code (RAC) and ecological risk indices (Er and RI). The results indicated that SCW treatment could eliminate the explosives, >99%, during the remediation, while the HM was effectively immobilized. The effect of water temperature on reducing the explosives and the risk of HMs in soil was observed. A marked increase in the non-bioavailable concentration of each HM was observed, and the leaching rate of HMs was decreased by 70-97% after SCW treatment at 250 °C, showing the effective immobilization of HMs. According to the RAC or RI, each tested HM showed no or low risk to the environment after treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Health risk assessment of heavy metal variability in sachet water sold in Ado-Odo Ota, South-Western Nigeria.

    Science.gov (United States)

    Emenike, PraiseGod Chidozie; Tenebe, Theophilus Imokhai; Omeje, Maxwell; Osinubi, Damilare Samuel

    2017-08-31

    The sales of sachet water (SW), also known as "pure water" (PW), in Nigeria is a lucrative business. It serves many people, especially low-income earners, by providing a more affordable access to safe drinking water when compared with table water. However, some of the producers of SW do not effectively treat raw water before packaging them for sale. This study investigates the presence and concentrations of heavy metals, such as chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), aluminum (Al), and zinc (Zn) in some samples of SW sold within Ota, Ogun State, Nigeria. Samples of SW from nine different producers were purchased for four consecutive weeks and analyzed to determine the concentrations of these heavy metals in them. Furthermore, health risk indicators, such as chronic daily intake (CDI) and health risk indices (HRI) for children and adults, were calculated separately. The metal concentrations were compared with allowable limits set by the World Health Organization (WHO), Nigerian Industrial Standard (NIS), and the United States Environmental Protection Agency (US EPA). High concentrations of Cr, Fe, and Al were found in all the nine samples and exceeded the maximum allowable limits (MAL) of all the standards considered. However, the concentrations of Zn, Mn, and Cu were within permissible limits. The HRIs of heavy metals were in the order of Cu > Fe > Zn > Mn > Al > Cr, but since the standard limits set for some metals were exceeded, proper and effective treatment is required to safeguard the health of consumers.

  9. Evidence of hydraulic lift for pre-rainy season leaf out and dry-season stem water enrichment in Sclerocarya birrea, a tropical agroforestry tree

    Science.gov (United States)

    Ceperley, Natalie; Mande, Theophile; Rinaldo, Andrea; Parlange, Marc B.

    2014-05-01

    We use stable isotopes of water as tracers to follow water use by five Sclerocarya birrea trees in a catchment in South Eastern Burkina Faso interspersed with millet fields, gallery forest, Sudanian savanna, and fallow fields. Isotopic ratios were determined from water extracted from stems of the trees and sub-canopy soil of two of them, while nearby ground water, precipitation, and surface water was sampled weekly. A unique configuration of sensors connected with a wireless sensor network of meteorological stations measured sub-canopy shading, the temperature and humidity in the canopy, through-fall, and soil moisture under two of the trees. Both water extracted from sap and water extracted from soil is extremely enriched in the dry season, but drop to levels close to the ground water in February or March, which coincides with the growth of leaves. Dates of leaf out were confirmed by changes in δDH and δO18 concentrations of water, photographic documentation & pixel analysis, and analysis of sub-canopy radiation and proceeded the rise in humidity and flow that was later detected in the sub-canopy soil, the trunk of the tree (sap-flow), and atmosphere (canopy VPD). Examination of the isotopic signature suggests that size of tree plays an important role in duration and timing of this leaf-out as well as the degree of enrichment during the peak of the dry season. Further examination of the isotopic signatures of the roots suggested that the trees are performing hydraulic redistribution, or lifting the ground water and "sharing it" with the soil in the rooting zone in the dry season. The enriched level of xylem in this case is a product of water loss, and enrichment, along the travel path of the water from the roots to the tip of the stem, as evidenced by the variation according to size of tree. Vapor pressure deficit, soil water, and soil moisture interactions support this picture of interacting controls, separate from hydrologic triggers on the water movement in

  10. Lipid oxidation in fish oil enriched oil-in-water emulsions and cream cheese with pre-emulsified fish oil is affected differently by the emulsifier used

    DEFF Research Database (Denmark)

    Horn, Anna Frisenfeldt; Nielsen, Nina Skall; Andersen, Ulf

    It is well-documented that a high intake of long chain omega-3 polyunsaturated fatty acids has several health beneficial effects in humans. Consequently, the interest in food products enriched with marine oils has increased during recent years. However, addition of these highly unsaturated fatty...... acids to foods invariably increases the risk of lipid oxidation. A possible strategy to avoid lipid oxidation and the consecutive development of unpleasant off-flavours is to protect the oil in a delivery emulsion in which the oil droplets are shielded from its possible pro-oxidative surroundings...... will include results from studies on lipid oxidation in simple oil-in-water emulsions prepared with milk proteins alone or combinations of milk proteins and phospholipids. In addition, a study on fish oil enriched cream cheese will be presented. In this study, the cream cheese was enriched with either neat...

  11. Survey of heavy metal pollution (copper, lead, zinc, cadmium, iron and manganese) in drinking water resources of Nurabad city, Lorestan, Iran 2013

    OpenAIRE

    GHodratolah Shams Khorramabadi; Abdolah Dargahi; Lila Tabandeh; Hatam Godini; Parvin Mostafaee

    2016-01-01

    Background: Healthy water passes through the pipelines from supply resources to consuming places in which passing from these stages may cause some cases of contamination like heavy metal contamination. Therefore, the aim of this study was to evaluate the contamination of heavy metals (copper, lead, zinc, cadmium, iron, and manganese) in water resources of Nurabad city of Lorestan in 2013. Materials and Methods: In this cross-sectional study, samples were collected from 7 wells of drinking...

  12. Bioavailability of heavy metals in fresh water Tilapia nilotica (Oreachromis niloticus Linnaeus, 1758): potential risk to fishermen and consumers.

    Science.gov (United States)

    El-Sadaawy, Manal M; El-Said, Ghada F; Sallam, Neama A

    2013-01-01

    The study was undertaken to assess the accumulation of some heavy metals (Cr, Co, Cu, Ni, Zn, Pb and Cd) in different tissues (muscle, gills, heart, liver, brain, bone and skin) of Tilapia nilotica. It is one of the most edible fish species in Egypt and was collected from a commercial fish farm in order to evaluate their potential risk to fishermen and consumers. This fish farm is fed with discharged water containing agricultural, industrial, sewage and domestic wastes. The length-weight relation and condition factor calculation of Tilapia nilotica samples showed a significant linear regression (r(2) = 0.920) and an average condition factor of 4.1 g/cm(3). This indicated that the health status for the studied fish samples was good. Metal pollution index (MPI) values for the determined heavy metals in the different tissues reflected that the muscle was the only tissue that had the lowest content. Provisional Tolerable Weekly Intake (PTWI) values for the investigated heavy metals were lower than those reported for the permissible limits. The data were evaluated by using ANOVA statistical analysis. For appraising the human health risk effects of heavy metals in fish muscle, estimated dietary intake (EDI) and hazard quotient (HQ) were determined. HQ levels indicated that Cr and Co were the only heavy metals among the determined ones that had values more than unity. Also, their relative contributions in fish consumptions were Cr> Co> Pb> Ni> Cu> Cd> Zn. The highest average HQ value of chromium determined in this study referred to the possible adverse effects of Cr on human health. Accordingly, the potential public health risks from dietary exposure to hazardous contaminants in fish species from fish farms must be continually subjected to research, regulation and debate.

  13. Mycobacteria in Water Used for Personal Hygiene in Heavy Industry and Collieries: A Potential Risk for Employees

    Directory of Open Access Journals (Sweden)

    Vit Ulmann

    2015-03-01

    Full Text Available Environmental mycobacteria (EM constitute a health risk, particularly for immunocompromised people. Workers in heavy industry and in collieries represent an at-risk group of people as their immunity is often weakened by long-term employment in dusty environments, frequent smoking and an increased occurrence of pulmonary diseases. This study was concerned with the presence of EM in non-drinking water used for the hygiene of employees in six large industrial companies and collieries. Over a period of ten years, 1096 samples of surface water treated for hygiene purposes (treated surface water and treated surface water diluted with mining water were examined. EM were detected in 63.4 and 41.5% samples of treated surface water and treated surface water diluted with mining water, respectively. Mycobacterium gordonae, M. avium-intracellulare and M. kansasii were the most frequently detected species. Adoption of suitable precautions should be enforced to reduce the incidence of mycobacteria in shower water and to decrease the infectious pressure on employees belonging to an at-risk group of people.

  14. [Transfer characteristic and source identification of soil heavy metals from water-level-fluctuating zone along Xiangxi River, three-Gorges Reservoir area].

    Science.gov (United States)

    Xu, Tao; Wang, Fei; Guo, Qiang; Nie, Xiao-Qian; Huang, Ying-Ping; Chen, Jun

    2014-04-01

    Transfer characteristics of heavy metals and their evaluation of potential risk were studied based on determining concentration of heavy metal in soils from water-level-fluctuating zone (altitude:145-175 m) and bank (altitude: 175-185 m) along Xiangxi River, Three Gorges Reservoir area. Factor analysis-multiple linear regression (FA-MLR) was employed for heavy metal source identification and source apportionment. Results demonstrate that, during exposing season, the concentration of soil heavy metals in water-level-fluctuation zone and bank showed the variation, and the concentration of soil heavy metals reduced in shallow soil, but increased in deep soil at water-level-fluctuation zone. However, the concentration of soil heavy metals reduced in both shallow and deep soil at bank during the same period. According to the geoaccumulation index,the pollution extent of heavy metals followed the order: Cd > Pb > Cu > Cr, Cd is the primary pollutant. FA and FA-MLR reveal that in soils from water-level-fluctuation zone, 75.60% of Pb originates from traffic, 62.03% of Cd is from agriculture, 64.71% of Cu and 75.36% of Cr are from natural rock. In soils from bank, 82.26% of Pb originates from traffic, 68.63% of Cd is from agriculture, 65.72% of Cu and 69.33% of Cr are from natural rock. In conclusion, FA-MLR can successfully identify source of heavy metal and compute source apportionment of heavy metals, meanwhile the transfer characteristic is revealed. All these information can be a reference for heavy metal pollution control.

  15. Developing selenium-enriched animal feed and biofuel from canola planted for managing Se-laden drainage waters in the westside of central California.

    Science.gov (United States)

    Bañuelos, G S; Da Roche, J; Robinson, J

    2010-03-01

    We studied the reuse of selenium (Se)-laden effluent for producing canola (Brassica napus) and subsequent bioproducts in central California. Canola was irrigated with poor quality waters [electrical conductivity (EC) of approximately 5 dS m(-1) sulfate-salinity, 5 mg B L(-1), and 0.25 mg Se L(-1)]. Typical seed yields were 2.2 metric tons ha(-1). Seeds were processed for their oil, and transesterified to produce ASTM-quality biodiesel (BD) blends. The resulting Se-enriched seed cake meal (containing approximately 2 mg Se kg(-1) DM) was used in a dairy feed trial. Seventy-two Jersey and Holstein cows, 36 respectively, were fed Se-enriched canola meal as 6.2% of their daily feed ration for five weeks. Blood and milk samples were collected weekly and analyzed for total Se. This study showed that Se-enriched canola meal did not significantly increase total blood Se content in either cow breed. Milk Se concentrations did, however, significantly increase to safe levels of 59 microg Se L(-1) and 52 microg Se L(-1) in Jersey and Holstein cows, respectively. The production of BD 20 biofuels and Se-enriched feed meal from canola irrigated with poor quality waters may help sustain similar phytomanagement strategies under Se-rich conditions.

  16. Phytoremediation: role of terrestrial plants and aquatic macrophytes in the remediation of radionuclides and heavy metal contaminated soil and water.

    Science.gov (United States)

    Sharma, Sunita; Singh, Bikram; Manchanda, V K

    2015-01-01

    Nuclear power reactors are operating in 31 countries around the world. Along with reactor operations, activities like mining, fuel fabrication, fuel reprocessing and military operations are the major contributors to the nuclear waste. The presence of a large number of fission products along with multiple oxidation state long-lived radionuclides such as neptunium ((237)Np), plutonium ((239)Pu), americium ((241/243)Am) and curium ((245)Cm) make the waste streams a potential radiological threat to the environment. Commonly high concentrations of cesium ((137)Cs) and strontium ((90)Sr) are found in a nuclear waste. These radionuclides are capable enough to produce potential health threat due to their long half-lives and effortless translocation into the human body. Besides the radionuclides, heavy metal contamination is also a serious issue. Heavy metals occur naturally in the earth crust and in low concentration, are also essential for the metabolism of living beings. Bioaccumulation of these heavy metals causes hazardous effects. These pollutants enter the human body directly via contaminated drinking water or through the food chain. This issue has drawn the attention of scientists throughout the world to device eco-friendly treatments to remediate the soil and water resources. Various physical and chemical treatments are being applied to clean the waste, but these techniques are quite expensive, complicated and comprise various side effects. One of the promising techniques, which has been pursued vigorously to overcome these demerits, is phytoremediation. The process is very effective, eco-friendly, easy and affordable. This technique utilizes the plants and its associated microbes to decontaminate the low and moderately contaminated sites efficiently. Many plant species are successfully used for remediation of contaminated soil and water systems. Remediation of these systems turns into a serious problem due to various anthropogenic activities that have

  17. Distribution, diffusive fluxes, and toxicity of heavy metals and PAHs in pore water profiles from the northern bays of Taihu Lake.

    Science.gov (United States)

    Lei, Pei; Zhang, Hong; Shan, Baoqing; Zhang, Bozheng

    2016-11-01

    Pore water plays a more significant role than do sediments in pollutant cycling dynamics. Also, concentrations of pollutants in pore water provide important information about their bioavailability or eco-toxicity; however, very few studies have focused on this topic. In this study, four duplicate sediment cores from three typical northern bays as well as the central part of Taihu Lake were collected to investigate the distribution, diffusive fluxes, and toxicity of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in pore water profiles, which will be good in understanding the mobility and toxicity of these toxic pollutants and achieving better environmental management. The diffusive fluxes of heavy metals across the sediment-water interface was estimated through Fick's First Law, and the toxicity of heavy metals and PAHs in pore water was assessed by applying a water quality index (interstitial water toxicity criteria unit, IWCTU) and a hazard index (HI), respectively. The average concentrations of Cr, Cu, Ni, Pb, and Zn in surface pore water were 18.8, 23.4, 12.0, 13.5, and 42.5 μg L-1, respectively. Also, concentrations of the selected heavy metals in both overlying water and pore water from Taihu Lake were all lower than the standard values of the environmental quality standards for surface water. The concentrations as the pore water depth increased, and the highest detected concentrations of heavy metals were recorded between 3 and 5 cm below the sediment surface. The average diffusive fluxes of these metals were 27.3, 24.8, 7.03, 7.81, and -3.32 μg (m2 day)-1, respectively, indicating export from sediment into overlying water, with the exception of Zn. There was a potential risk of toxicity, mainly from Pb and Cu, indicating that heavy metals in pore water had slight to moderate impact on sediment-dwelling organisms by values of the IWCTU and the Nemeraw index. The total PAH concentrations in pore water were higher than those in overlying water

  18. Enrichment and low-level determination of glyphosate, aminomethylphosphonic acid and glufosinate in drinking water after cleanup by cation exchange resin.

    Science.gov (United States)

    Küsters, Markus; Gerhartz, Michael

    2010-04-01

    For the determination of glyphosate, aminomethylphosphonic acid and glufosinate in drinking water, different procedures of enrichment and cleanup were examined using anion exchange or SPE. In many cases interactions of, e.g. alkaline earth metal ions especially calcium could be observed during enrichment and cleanup resulting in loss of analytes. For that reason, a novel cleanup and enrichment procedure for the determination of these phosphonic acid herbicides has been developed in drinking water using cation-exchange resin. In summary, the cleanup procedure with cation-exchange resin developed in this study avoids interactions as described above and is applicable to calcium-rich drinking water samples. After derivatization with 9-fluorenylmethylchloroformate followed by LC with fluorescence detection, LOD of 12, 14 and 12 ng/L and mean recoveries from real-world drinking water samples of 98+/-9, 100+/-16 and 101+/-11% were obtained for glyphosate, aminomethylphosphonic acid and glufosinate, respectively. The low LODs and the high precision permit the analysis of these phosphonic acid herbicides according to the guidelines of the European Commission.

  19. Change of water sources reduces health risks from heavy metals via ingestion of water, soil, and rice in a riverine area, South China.

    Science.gov (United States)

    Zhang, Li'e; Mo, Zhaoyu; Qin, Jian; Li, Qin; Wei, Yanhong; Ma, Shuyan; Xiong, Yuxia; Liang, Guiqiang; Qing, Li; Chen, Zhiming; Yang, Xiaobo; Zhang, Zhiyong; Zou, Yunfeng

    2015-10-15

    This study evaluates the effect of water source change on heavy metal concentrations in water, paddy soil, and rice, as well as the health risks to residents of three riverine communities in South China. The results show that after substituting the sources of drinking water, heavy metal levels (except for Pb at Tangjun) in drinking water were below WHO guideline values and the potential risk from drinking water may be negligible. The As (46.2-66.8%), Pb (65.7-82.6%), Cd (50.8-55.0%), and Hg (28.3-32.6%) concentrations in paddy soils in Sanhe and Lasha significantly (psoil ingestion and rice consumption. Despite that total non-carcinogenic and carcinogenic risks at Sanhe and Lasha were significantly decreased, they still exceeded the maximum acceptable limits recommended by US EPA, indicating that residents of these two communities remain at high risks of both non-cancer and cancer effects. Copyright © 2015. Published by Elsevier B.V.

  20. Black water sludge reuse in agriculture: Are heavy metals a problem?

    NARCIS (Netherlands)

    Tervahauta, T.H.; Rani, S.; Leal, L.H.; Buisman, C.J.N.; Zeeman, G.

    2014-01-01

    Heavy metal content of sewage sludge is currently the most significant factor limiting its reuse in agriculture within the European Union. In the Netherlands most of the produced sewage sludge is incinerated, mineralizing the organic carbon into the atmosphere rather than returning it back to the

  1. Heavy Metal Contamination of Soil and Surface Water in the Arufu

    African Journals Online (AJOL)

    Dr. Annku

    companies has been intermittent since 1921. (Pargater,1959). At present, the mines are aban- doned due to the exhaustion of ore reserves with- out any proper management of the mines and tail- ings. According to Jung (2001), this mine waste could generate point source of heavy metal pollution in the local environment as ...

  2. An analysis of some heavy metals in the water, sediments and some ...

    African Journals Online (AJOL)

    The concentration of heavy metals(Zn, Ni, Pb, Cd and Cu) in the muscle of three fishery organisms (Chrysicththys nigrodigitatus, Sarotherodon galilaeus and Peneaus monodon)and in environmental samples of waterand sediment were tested in Yewa Lagoon, Nigeria. Five fishing villages along the lagoon were selected as ...

  3. determination of the level of some heavy metals in water collected ...

    African Journals Online (AJOL)

    DR. AMINU

    In view of this, levels of some heavy metals, Zn, Pb, Cr, Cu, Ni, Co, Ag, Fe and. Mn were determined in .... Moreover, hyper reactivity and learning disorders have been ... Environmental Pollution (Series) B7, 11: 241 – 253. Connel, B.S., Cox, M.

  4. Environmentally friendly chitosan/PEI-grafted magnetic gelatin for the highly effective removal of heavy metals from drinking water

    Science.gov (United States)

    Li, Bingbing; Zhou, Feng; Huang, Kai; Wang, Yipei; Mei, Surong; Zhou, Yikai; Jing, Tao

    2017-02-01

    The development of environmentally friendly sorbents with a high adsorption capacity is an essential problem in the removal of heavy metals from drinking water. In this study, magnetic gelatin was prepared using transglutaminase as a cross-linker, which could only catalyze an acyl-transfer reaction between lysine and glutamine residues of the gelatin and not affect other amino groups. Therefore, it was beneficial for the further modification based on the amino groups, and did not affect the spatial structure of gelatin, which can effectively prevent the embedding of active sites in the polymer matrix. After modification with the chitosan/polyethylenimine copolymers, the numbers of amino groups was greatly increased, and the magnetic composites exhibited a high adsorption capacity, excellent water compatibility and simple magnetic separation. The adsorption capacities of lead and cadmium were 341 mg g-1 and 321 mg g-1, respectively, which could be used for the removal of metal ions in drinking water.

  5. Pressure-assisted electrokinetic injection for on-line enrichment in capillary electrophoresis-mass spectrometry: a sensitive method for measurement of ten haloacetic acids in drinking water.

    Science.gov (United States)

    Zhang, Huijuan; Zhu, Jiping; Aranda-Rodriguez, Rocio; Feng, Yong-Lai

    2011-11-07

    Haloacetic acids (HAAs) are by-products of the chlorination of drinking water containing natural organic matter and bromide. A simple and sensitive method has been developed for determination of ten HAAs in drinking water. The pressure-assisted electrokinetic injection (PAEKI), an on-line enrichment technique, was employed to introduce the sample into a capillary electrophoresis (CE)-electrospray ionization-tandem mass spectrometry system (ESI-MS/MS). HAAs were monitored in selected reaction monitoring mode. With 3 min of PAEKI time, the ten major HAAs (HAA10) in drinking water were enriched up to 20,000-fold into the capillary without compromising resolution. A simple solid phase clean-up method has been developed to eliminate the influence of ionic matrices from drinking water on PAEKI. Under conditions optimized for mass spectrometry, PAEKI and capillary electrophoresis, detection limits defined as three times ratio of signal to noise have been achieved in a range of 0.013-0.12 μg L(-1) for ten HAAs in water sample. The overall recoveries for all ten HAAs in drinking water samples were between 76 and 125%. Six HAAs including monochloro- (MCAA), dichloro- (DCAA), trichloro- (TCAA), monobromo- (MBAA), bromochloro- (BCAA), and bromodichloroacetic acids (BDCAA) were found in tap water samples collected. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  6. Coating Fe3O4 magnetic nanoparticles with humic acid for high efficient removal of heavy metals in water.

    Science.gov (United States)

    Liu, Jing-fu; Zhao, Zong-shan; Jiang, Gui-bin

    2008-09-15

    Humic acid (HA) coated Fe3O4 nanoparticles (Fe3O4/HA) were developed for the removal of toxic Hg(II), Pb(II), Cd(II), and Cu(II) from water. Fe3O4/HA were prepared by a coprecipitation procedure with cheap and environmentally friendly iron salts and HA. TOC and XPS analysis showed the as-prepared Fe3O4/HA contains approximately 11% (w/w) of HA which are fractions abundant in O and N-based functional groups. TEM images and laser particle size analysis revealed the Fe3O4/HA (with approximately 10 nm Fe3O4 cores) aggregated in aqueous suspensions to form aggregates with an average hydrodynamic size of approximately 140 nm. With a saturation magnetization of 79.6 emu/g, the Fe3O4/HA can be simply recovered from water with magnetic separations at low magnetic field gradients within a few minutes. Sorption of the heavy metals to Fe3O4/HA reached equilibrium in less than 15 min, and agreed well to the Langmuir adsorption model with maximum adsorption capacities from 46.3 to 97.7 mg/g. The Fe3O4/HA was stable in tap water, natural waters, and acidic/ basic solutions ranging from 0.1 M HCl to 2 M NaOH with low leaching of Fe (< or = 3.7%) and HA (< or = 5.3%). The Fe3O4/HA was able to remove over 99% of Hg(ll) and Pb(ll) and over 95% of Cu(II) and Cd(II) in natural and tap water at optimized pH. Leaching back of the Fe3O4/HA sorbed heavy metals in water was found to be negligible.

  7. Analysis of removal alternatives for the Heavy Water Components Test Reactor at the Savannah River Site. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Owen, M.B.

    1997-04-01

    This engineering study evaluates different alternatives for decontamination and decommissioning of the Heavy Water Components Test Reactor (HWCTR). Cooled and moderated with pressurized heavy water, this uranium-fueled nuclear reactor was designed to test fuel assemblies for heavy water power reactors. It was operated for this purpose from march of 1962 until December of 1964. Four alternatives studied in detail include: (1) dismantlement, in which all radioactive and hazardous contaminants would be removed, the containment dome dismantled and the property restored to a condition similar to its original preconstruction state; (2) partial dismantlement and interim safe storage, where radioactive equipment except for the reactor vessel and steam generators would be removed, along with hazardous materials, and the building sealed with remote monitoring equipment in place to permit limited inspections at five-year intervals; (3) conversion for beneficial reuse, in which most radioactive equipment and hazardous materials would be removed and the containment building converted to another use such as a storage facility for radioactive materials, and (4) entombment, which involves removing hazardous materials, filling the below-ground structure with concrete, removing the containment dome and pouring a concrete cap on the tomb. Also considered was safe storage, but this approach, which has, in effect, been followed for the past 30 years, did not warrant detailed evaluation. The four other alternatives were evaluate, taking into account factors such as potential effects on the environment, risks, effectiveness, ease of implementation and cost. The preferred alternative was determined to be dismantlement. This approach is recommended because it ranks highest in the comparative analysis, would serve as the best prototype for the site reactor decommissioning program and would be most compatible with site property reuse plans for the future.

  8. Prediction of the moderator temperature field in a heavy water reactor based on a cellular neural network

    Directory of Open Access Journals (Sweden)

    S.O. Starkov

    2017-06-01

    Full Text Available Reactors with heavy water coolants and moderators have been used extensively in today's power industry. Monitoring of the moderator condition plays an important role in ensuring normal operation of a power plant. A cellular neural network, the architecture of which has been adapted for hardware implementation, is proposed for use in a system for prediction of the heavy water moderator temperature. A reactor model composed in accordance with the CANDU Darlington heavy water reactor design was used to form the training sample collection and to control correct operation of the neural network structure. The sample components for the adjustment and configuration of the network topology include key parameters that characterize the energy generation process in the core. The paper considers the feasibility of the temperature prediction only for the calandria's central cross-section. To solve this problem, the cellular neural network architecture has been designed, and major parts of the digital computational element and methods for their implementation based on an FPLD have also been developed. The method is described for organizing an optical coupling between individual neural modules within the network, which enables not only the restructuring of the topology in the training process, but also the assignment of priorities for the propagation of the information signals of neurons depending on the activity in a situation analysis at the neural network structure inlet. Asynchronous activation of cells was used based on an oscillating fractal network, the basis for which was a modified ring oscillator. The efficiency of training the proposed architecture using stochastic diffusion search algorithms is evaluated. A comparative analysis of the model behavior and the results of the neural network operation have shown that the use of the neural network approach is effective in safety systems of power plants.

  9. Geochemistry and magnetic measurements of suspended sediment in urban sewage water vis-à-vis quantification of heavy metal pollution in Ganga and Yamuna Rivers, India.

    Science.gov (United States)

    Chakarvorty, Munmun; Dwivedi, Akhil Kumar; Shukla, Anil Dutt; Kumar, Sujeet; Niyogi, Ambalika; Usmani, Mavera; Pati, Jayanta Kumar

    2015-09-01

    Sewage water is becoming a key source of heavy metal toxicity in large river systems worldwide and the two major Himalayan Rivers in India (Ganga and Yamuna) are severely affected. The high population density in the river banks combined with increased anthropogenic and industrial activities is contributing to the heavy metal pollution in these rivers. Geochemical data shows a significant increase in the concentration of all heavy metals (Pb, 48-86 ppm; Zn, 360-834 ppm; V, 45-101 ppm; Ni, 20-143 ppm; Cr, 79-266 ppm; Co, 8.62-22.12 ppm and Mn, 313-603 ppm) in sewage and mixed water (sewage and river water confluence site) samples due to increased effluent discharge from the catchment area. The ΣREE content of sewage water (129 ppm) is lower than the average mixed water samples (142 ppm). However, all the samples show similar REE pattern. The mass magnetic susceptibility (Xlf) values of suspended sediments (28 to 1000 × 10(-8) m(3) kg(-1)) indicate variable concentration of heavy metals. The Xlf values show faint positive correlation with their respective bulk heavy metal contents in a limited sample population. The present study comprising geochemical analysis and first magnetic measurement data of suspended sediments in water samples shows a strongly polluted nature of Ganga and Yamuna Rivers at Allahabad contrary to the previous report mainly caused by overtly polluted city sewage water.

  10. Multiple biomarker responses (serum biochemistry, oxidative stress, genotoxicity and histopathology) in Channa punctatus exposed to heavy metal loaded waste water.

    Science.gov (United States)

    Javed, Mehjbeen; Ahmad, Md Irshad; Usmani, Nazura; Ahmad, Masood

    2017-05-10

    Experiments were conducted to investigate the health of fish Channa punctatus inhabiting heavy metal-loaded waste water. Heavy metals in the order of Fe > Mn > Zn > Co > Ni > Cu = Cr were present in the waste water. Gills had high metal load followed by liver and then kidney. Albumin, albumin to globulin (A:G) ratio, triglyceride, high density lipoprotein (HDL) and very low density lipoprotein (VLDL) were found to be lower but phospholipid, low density lipoprotein (LDL), total protein, lipid and cholesterol were higher as compared to the reference. Oxidative stress markers such as superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST) and lipid peroxidation (LPO) were significantly higher in all tissues, whereas reduced glutathione (GSH) levels were comparatively low. Damage to DNA was observed with significantly higher mean tail length of comets in the exposed fish gill cells (30.9 µm) followed by liver (24.3 µm) and kidney (20.6 µm) as compared to reference fish (5.2, 4.8 and 5.9 µm respectively). Histopathology in gill, liver and kidney also showed marked damage. Integrated biochemical, oxidative stress, genotoxicity and histopathological findings are valuable biomarkers for native fish adaptive patterns, and monitoring of water quality/pollution of freshwater ecosystems.

  11. Water supply at heavy disaster (earthquake); Saigaiji (jishinji) no mizu jijo

    Energy Technology Data Exchange (ETDEWEB)

    Okada, S. [College of Science and Technology, Tohoku, Sendai (Japan)

    1999-03-05

    With the destructive earthquake recently visited Hanshin/Awaji Districts as a momentum, importance to secure water at an emergency has seriously been recongnized. This papaer describes the administrative actions, technical level, future problems or the like in securing water. Practically, the countermeasure taken against the disaster, the water volume required for emergency supply, the water quality by applications, the example of the administrative emergency water supply system, and the water source at the disaster are outlined. (author)

  12. TiO2/bone composite materials for the separation of heavy metal impurities from waste water solutions

    Science.gov (United States)

    Dakroury, G.; Labib, Sh.; Abou El-Nour, F. H.

    2012-09-01

    Pure bone material obtained from cow meat, as apatite-rich material, and TiO2-bone composite materials are prepared and studied to be used for heavy metal ions separation from waste water solutions. Meat wastes are chemically and thermally treated to control their microstructure in order to prepare the composite materials that fulfill all the requirements to be used as selective membranes with high performance, stability and mechanical strength. The prepared materials are analyzed using Hg-porosimetry for surface characterization, energy dispersive X-ray spectroscopy (EDAX) for elemental analysis and Fourier transform infrared spectroscopy (FTIR) for chemical composition investigation. Structural studies are performed using X-ray diffraction (XRD). Microstructural properties are studied using scanning electron microscopy (SEM) and specific surface area studies are performed using Brunauer-Emmet-Teller (BET) method. XRD studies show that multiphase structures are obtained as a result of 1h sintering at 700-1200 °C for both pure bone and TiO2-bone composite materials. The factors affecting the transport of different heavy metal ions through the selected membranes are determined from permeation flux measurements. It is found that membrane pore size, membrane surface roughness and membrane surface charge are the key parameters that control the transport or rejection of heavy metal ions through the selected membranes.

  13. Assessment of heavy metals in the industrial effluents, tube-wells and municipal supplied water of Dehradun, India.

    Science.gov (United States)

    Kulshrestha, Shail; Awasthi, Alok; Dabral, S K

    2013-07-01

    The bio-geochemical cycles of metals involve the lands, rivers, oceans and the atmosphere. Although a large number of metals are introduced to the water bodies during their mining and extraction processes and geochemical weathering of rocks, but the role of domestic and industrial wastes is predominant and of much concern. Increased industrial activities has increased the incidence of percolation of toxic metal ions to the soil and water bodies and presently their presence in ecosystem, have reached to an alarming level that environmentalists are finding it difficult to enforce control measures. Human activities and large number of small and big industrial units are increasingly discharging deleterious metals present in the effluents and wastes, to the environment and aquatic systems and have contaminated heavily even the ground water. The toxic metals have a great tendency of bioaccumulation through which they enter the food chain system and ultimately affect adversely the life on this planet Earth in various ways. Further, due to contamination of irrigation system by the harmful Chemicals and toxic metals, the farm products, vegetables, fruits, potable water and even milk is not spared. This paper describes the assessment of the heavy metal concentration in various industrial effluents of the surrounding area. Various physico-chemical characteristics of the effluents collected from various sites are also reported. To assess the status of ground water quality, water samples from four tube wells of different localities of the area and four drinking water samples supplied by Municipal Distribution System were also analyzed.

  14. Response of vegetation to carbon dioxide. Growth, yield and plant water relationships in sweet potatoes in response to carbon dioxide enrichment 1986

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    In the summer of 1985, under the joint program of US Department of Energy, Carbon Dioxide Division, and Tuskegee University, experiments were conducted to study growth, yield, photosynthesis and plant water relationships in sweet potato plants growth in an enriched CO{sub 2} environment. The main experiment utilized open top chambers to study the effects of CO{sub 2} and soil moisture on growth, yield and photosynthesis of field-grown plants. In addition, potted plants in open top chambers were utilized in a study of the effects of different CO{sub 2} concentrations on growth pattern, relative growth rate, net assimilation rate and biomass increment at different stages of development. The interaction effects of enriched CO{sub 2} and water stress on biomass production, yield, xylem potential, and stomatal conductance were also investigated. The overall results of the various studies are described.

  15. New limit on the proton life-time independent on channel from the neutrino experiments with heavy water

    CERN Document Server

    Tretyak, V I

    2002-01-01

    Experimental data on the number of neutrons born in the heavy water targets of the large neutrino detectors are used to set the limit on the proton life-time independently on decay mode through the reaction d -> n + ?. The best up-to-date limit tau sub p > 4x10 sup 2 sup 3 yr with 95% C.L. is derived from the measurements with D sub 2 O target (mass 267 kg) installed near the Bugey reactor. This value can be improved by six orders of magnitude with future data accumulated with the SNO detector containing 1000 t of D sub 2 O.

  16. Assessment Of Heavy Metal Contamination Of Water Sources From Enyigba Pb-Zn District South Eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Nnabo Paulinus N

    2015-08-01

    Full Text Available Abstract A total of thirty 30 water samples were collected from the Enyigba PbZn mining district to assess the contamination of the water sources as a result of mining of lead and zinc minerals in the area. This comprises of 12 samples of surface water 14 from mine ponds and 4 from underground borehole water. The samples were acidified to stabilize the metals for periods more than four days without the use of refrigeration. The acidified water samples were analysed by a commercial laboratory at Projects Development Institute PRODA Enugu using Atomic Absorption Spectroscopy AAS. The elements determined by this method are lead Pb zinc Zn copper Cu arsenic As cadmium Cd nickel Ni manganese Mn and cobalt Co. The result and analysis of contamination factor showed that in surface water Cd had the highest concentration followed by As and Pb while Ni had the lowest. In mine ponds Cd also had the highest concentration and followed by Pb and As and Ni the lowest. In borehole water Cd has the highest concentration followed by Pb and As while Ni had the lowest concentration. Compared to WHO permissible limits the contamination of the heavy metals in all water sources are in order CdAsPbNiZnCu. In surface water the order is CdAsPbNiZnCu in mine ponds it is CdPbAsNiZnCu and in borehole water the order is CdAsPbZnNiCu. The calculated contamination factors show very high contamination status for Cd Pb and As. These levels of contamination and values indicate that under the prevailing conditions and environmental regulations in Nigeria the mining district would face major and hazardous discharges of these metals to the water sources.

  17. Water contamination with heavy metals and trace elements from Kilembe copper mine and tailing sites in Western Uganda; implications for domestic water quality.

    Science.gov (United States)

    Abraham, Mwesigye R; Susan, Tumwebaze B

    2017-02-01

    The mining and processing of copper in Kilembe, Western Uganda, from 1956 to 1982 left over 15 Mt of cupriferous and cobaltiferous pyrite dumped within a mountain river valley, in addition to mine water which is pumped to the land surface. This study was conducted to assess the sources and concentrations of heavy metals and trace elements in Kilembe mine catchment water. Multi-element analysis of trace elements from point sources and sinks was conducted which included mine tailings, mine water, mine leachate, Nyamwamba River water, public water sources and domestic water samples using ICP-MS. The study found that mean concentrations (mg kg-1) of Co (112), Cu (3320), Ni (131), As (8.6) in mine tailings were significantly higher than world average crust and were being eroded and discharged into water bodies within the catchment. Underground mine water and leachate contained higher mean concentrations (μg L-1) of Cu (9470), Co (3430) and Ni (590) compared with background concentrations (μg L-1) in un contaminated water of 1.9, 0.21 and 0.67 for Cu, Co and Ni respectively. Over 25% of household water samples exceeded UK drinking water thresholds for Al of 200 μg L-1, Co exceeded Winsconsin (USA drinking) water thresholds of 40 μg L-1 in 40% of samples while Fe in 42% of samples exceeded UK thresholds of 200 μg L-1. The study however found that besides mining activities, natural processes of geological weathering also contributed to Al, Fe, and Mn water contamination in a number of public water sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Highly Efficient Luminescent Metal-Organic Framework for the Simultaneous Detection and Removal of Heavy Metals from Water.

    Science.gov (United States)

    Rudd, Nathan D; Wang, Hao; Fuentes-Fernandez, Erika M A; Teat, Simon J; Chen, Feng; Hall, Gene; Chabal, Yves J; Li, Jing

    2016-11-09

    We have designed and synthesized an isoreticular series of luminescent metal-organic frameworks (LMOFs) by incorporating a strongly emissive molecular fluorophore and functionally diverse colinkers into Zn-based structures. The three-dimensional porous networks of LMOF-261, -262, and -263 represent a unique/new type of nets, classified as a 2-nodal, (4,4)-c net (mot-e type) with 4-fold, class IIIa interpenetration. All compounds crystallize in a body-centered tetragonal crystal system (space group I4 1 /a). A systematic study has been implemented to analyze their interactions with heavy metals. LMOF-263 exhibits impressive water stability, high porosity, and strong luminescence, making it an excellent candidate as a fluorescent chemical sensor and adsorbent for aqueous contaminants. It is extremely responsive to toxic heavy metals at a parts per billion level (3.3 ppb Hg 2+ , 19.7 ppb Pb 2+ ) and demonstrates high selectivity for heavy metals over light metals, with detection ratios of 167.4 and 209.5 for Hg 2+ /Ca 2+ and Hg 2+ /Mg 2+ , respectively. Mixed-metal adsorption experiments also show that LMOF-263 selectively adsorbs Hg 2+ over other heavy metal ions in addition to light metals. The Pb 2+ K SV value for LMOF-263 (55,017 M -1 ) is the highest among LMOFs reported to date, and the Hg 2+ K SV value is the second highest (459,446 M -1 ). LMOF-263 exhibits a maximum adsorption capacity of 380 mg Hg 2+ /g. The Hg 2+ adsorption process follows pseudo-second-order kinetics, removing 99.1% of the metal within 30 min. An in situ XPS study provides insight to help understand the interaction mechanism between Hg 2+ and LMOF-263. No other MOFs have demonstrated such a high performance in both the detection and the capture of Hg 2+ from aqueous solution.

  19. Analysis of heavy metal content of Pb in ballast water tank of commercial vessels in port of Tanjung Emas Semarang, Central Java province

    Science.gov (United States)

    Tjahjono, Agus; Bambang, Azis Nur; Anggoro, Sutrisno

    2017-03-01

    Commercial vessels that do not conduct ballast water exchange, in accordance with International Convention Ballast Water Management, will endager the environment of ports. This research is aimed to know the metal content in ballast water tank of commercial vessels that have not performed ballast water exchange, in accordance with regulations of International Maritime Organization (IMO). The research about the heavy metal content of ballast water of commercial vessels, both passenger or cargo vessels, berthing in Port of Tanjung Emas Semarang (PTES), has been conducted by using method of AAS (Atomic Absorption Spectroscopy). Sample was gathered from vessels berthed in PTES, dated on December 18th 2014 to October 21st 2015. Results of the research show that the mean content of Pb in ballast water tank is 0.37192 mg/l. Based on the Decree of Minister of Environment Number 51/2004, the heavy metal content of Pb in ballast water tank has exceeded the quality standards of port waters.

  20. Spatio-temporal impacts of dairy lagoon water reuse on soil: Heavy metals and salinity

    Science.gov (United States)

    Diminishing freshwater resources have brought attention to the reuse of degraded water as a water resource rather than a disposal problem. Dairy lagoon water is degraded water that is often in large supply on concentrated animal feeding operations (CAFOs), but the impact and sustainability of its r...

  1. Risk-based analysis of environmental monitoring data: application to heavy metals in North Carolina surface waters.

    Science.gov (United States)

    Preston, Benjamin L; Shackelford, Jeremiah

    2002-08-01

    The state of North Carolina's Department of Environment and Natural Resources (NCDENR) conducts routine water quality monitoring throughout the state to assess the health of aquatic systems. The current study reports the results of a retrospective (1990-2000) ecological risk assessment of six heavy metals (arsenic, cadmium, copper, lead, mercury, and zinc) in 17 North Carolina basins that was conducted to estimate the risk of heavy metal toxicity to freshwater organisms and assess the sufficiency of NCDENR's monitoring data to identify water-quality-related ecological threats. Acute and chronic ecotoxicological thresholds (ETs) were calculated for each metal based upon the 10th percentile of species sensitivity distributions and were normalized for water hardness. Statewide probabilities (expressed as percentages) of a random sample exceeding acute or chronic ETs among the six metals ranged from 0.01% to 12.19% and 0.76% to 21.21%, respectively, with copper having the highest and arsenic and mercury the lowest risk. Basin-specific probabilities varied significantly depending upon water hardness and presumably watershed development. Although the majority of specific sites where data were collected were at low risk for metal toxicity, some specific sites had a high probability of toxic events associated with one or more metals. Analytical detection limits for metals were frequently higher than estimated chronic ET, limiting the ability to assess the risk of chronic toxicity in soft-water basins. Results suggest risk-based criteria may be useful for assessing and validating the sufficiency of monitoring programs and prioritizing management goals.

  2. Comparative Studies of the Phytoextraction Capacity of Five Aquatic Plants in Heavy Metal Contaminated Water

    OpenAIRE

    Buta, Erzsébet; Anamária TÖRÖK; Bilassé ZONGO; Maria CANTOR; Mihai BUTA; Majdik, Cornelia

    2014-01-01

    The uptake capacity of the aquatic plants (Salvinia natans Kunth., Eichhornia crassipes Mart., Lemna minor L., Elodea canadensis Michx., Pistia stratiotes L.) was analyzed in phytoextraction of Cu2+, Zn2+, and Cd2+. It was attend to study the plants capacity comparatively using mono and multimetallic systems. In particular, the chlorophyll, protein and carotenoids contents were studied during heavy metals uptake, in order to observe the stress effect on plants. The results obtained for the m...

  3. Monitoring of heavy metal load - by mosses or rain water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ruoho-Airola, T. [Finnish Meteorological Inst., Helsinki (Finland); Maekelae, K. [National Board of Waters and the Environment, Helsinki (Finland)

    1995-12-31

    The deposition of heavy metals is usually determined from precipitation chemistry but the moss technique has been increasingly used, particularly in the Nordic countries. Some international monitoring programmes, e.g. UN/ECE Integrated Monitoring, give them as alternative methods. However, their comparability has not been sufficiently determined. This study compares the two monitoring methods for Pb, Cd, Cu and Zn, which have different sources. The metal industry is an important source of Pb and Cd emissions. Long- range transport as well as traffic and local emissions are also important sources for Pb. The use of fertilizers and fossil fuels also result in Cd emissions. Cu and Zn are emitted from metal industries and local sources. Unlike Pb and Cd, Cu and Zn are essential elements for living organisms. Cu and Zn are needed in many enzymes and Zn in proteins. Mosses are thought to take all their nutrients from the air. The deposition of heavy metals is also effectively retained by mosses and may be used to indicate levels of heavy metal deposition. In northern countries the mosses are isolated from air (and therefore also from deposition) by snow in winter. In this study both the bulk deposition of the whole year (later `total deposition`) and the bulk deposition of the snow-free period (later `bare ground deposition`) are compared to the metal concentrations in mosses. (author)

  4. The Treatment of Waste Waters Containing Heavy Metals by Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Dana Gešperová

    2004-12-01

    Full Text Available This study presents the synthesis and the characterization of the structural and sorption properties of magnetic nanoscale particles, which play a significant role in wastewater treatment technologies.Aqueous suspensions of magnetic particles were prepared by co-precipitation of Fe(III and Fe(II in the presence of NH4OH. Adsorption of heavy metal ions adsorption from single metal aqueous solutions was investigated in batch adsorption–equilibrium experiments. Magnetic particles were used in the adsorption of selected bivalent heavy metal ions, i.e. Cd(II, Cu(II and Pb(II from aqueous media containing different amounts of these ions (20–400 mg.l-1 and at different pH values of 2.0-8.0 at the sorbent concentration of 2 g.l-1. The model solutions of Cu(NO3 2, Cd(NO3 2, Pb(NO32 were used to realize the adsorption tests. The pH of the solutions was adjusted with a suitable concentration of NaOH and HNO3.Based on the experimental results it was observed that heavy metal ions could be adsorbed by nanoscale magnetic particles with the significant adsorption capacity.

  5. Heavy metal removal from water/wastewater by nanosized metal oxides: a review.

    Science.gov (United States)

    Hua, Ming; Zhang, Shujuan; Pan, Bingcai; Zhang, Weiming; Lv, Lu; Zhang, Quanxing

    2012-04-15

    Nanosized metal oxides (NMOs), including nanosized ferric oxides, manganese oxides, aluminum oxides, titanium oxides, magnesium oxides and cerium oxides, provide high surface area and specific affinity for heavy metal adsorption from aqueous systems. To date, it has become a hot topic to develop new technologies to synthesize NMOs, to evaluate their removal of heavy metals under varying experimental conditions, to reveal the underlying mechanism responsible for metal removal based on modern analytical techniques (XAS, ATR-FT-IR, NMR, etc.) or mathematical models, and to develop metal oxide-based materials of better applicability for practical use (such as granular oxides or composite materials). The present review mainly focuses on NMOs' preparation, their physicochemical properties, adsorption characteristics and mechanism, as well as their application in heavy metal removal. In addition, porous host supported NMOs are particularly concerned because of their great advantages for practical application as compared to the original NMOs. Also, some magnetic NMOs were included due to their unique separation performance. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. WHO water quality standards Vs Synergic effect(s) of fluoride, heavy metals and hardness in drinking water on kidney tissues

    Science.gov (United States)

    Wasana, Hewa M. S.; Perera, Gamage D. R. K.; Gunawardena, Panduka De S.; Fernando, Palika S.; Bandara, Jayasundera

    2017-02-01

    Despite WHO standards, waterborne diseases among the human being are rising alarmingly. It is known that the prolong exposure to contaminated water has major impact on public health. The effect of chemical contaminations in drinking water on human being is found to be chronic rather than acute and hence can be defined “consumption of contaminated drinking water could be a silent killer”. As the WHO recommended water quality standards are only for individual element and synergic effects of trace metals and anions have not been considered, investigation of synergic effects of trace metals and anions and their effect on human being is of prime important research. By an animal trial, we investigated the synergic effect(s) of heavy metals, aluminium, arsenic, fluoride and hardness in drinking water on kidney tissues of mice. Our investigation strongly suggests existing of a synergic effect especially among Cd, F and hardness of water which could lead to severe kidney damage in mice, even at WHO maximum recommended levels. Hence, the synergic effect(s) of trace metals, fluoride and hardness present in drinking water should be investigated meticulously when stipulating the water quality at WHO maximum recommended levels.

  7. WHO water quality standards Vs Synergic effect(s) of fluoride, heavy metals and hardness in drinking water on kidney tissues.

    Science.gov (United States)

    Wasana, Hewa M S; Perera, Gamage D R K; Gunawardena, Panduka De S; Fernando, Palika S; Bandara, Jayasundera

    2017-02-14

    Despite WHO standards, waterborne diseases among the human being are rising alarmingly. It is known that the prolong exposure to contaminated water has major impact on public health. The effect of chemical contaminations in drinking water on human being is found to be chronic rather than acute and hence can be defined "consumption of contaminated drinking water could be a silent killer". As the WHO recommended water quality standards are only for individual element and synergic effects of trace metals and anions have not been considered, investigation of synergic effects of trace metals and anions and their effect on human being is of prime important research. By an animal trial, we investigated the synergic effect(s) of heavy metals, aluminium, arsenic, fluoride and hardness in drinking water on kidney tissues of mice. Our investigation strongly suggests existing of a synergic effect especially among Cd, F and hardness of water which could lead to severe kidney damage in mice, even at WHO maximum recommended levels. Hence, the synergic effect(s) of trace metals, fluoride and hardness present in drinking water should be investigated meticulously when stipulating the water quality at WHO maximum recommended levels.

  8. The occurrence of heavy metals and metal-resistant bacteria in water and bottom sediments of the Straszyn reservoir (Poland

    Directory of Open Access Journals (Sweden)

    Kulbat Eliza

    2017-01-01

    Full Text Available The aim of this study is to investigate the distribution of selected heavy metals and metal–resistant bacteria in water and bottom sediments of the surface drinking water reservoir for Gdańsk. The following sequence of metals in regard to metal concentration in sediments can be written down: Zn > Pb > Cu > Cd. The evaluation of metals accumulation was performed using the Müller index, to indicate the bottom sediment's contamination and geochemical classification of sediment quality according to Polish standards. The Müller geochemical index was changing in a wide range: < 1–4.1. Although the maximum value of Müller's geochemical index determined for copper indicates that the sediment is ‘strongly contaminated’, in general the analysed bottom sediments were classified as the I and II category according to Polish geochemical standards. From the microbiological side a significant part of heterotrophic bacteria isolated from the bottom sediment and surface water (raw and treated water showed a resistance to 0.2 mM and 2 mM concentrations of zinc, copper and lead. The highest percentages of metal–resistant bacteria were recorded in the sediments of the reservoir (60%–88%. The share of metal–resistant strains in the raw water was significantly lower (34%–61%. The results indicate also that water treatment processes may contribute to the selection of resistant strains.

  9. The occurrence of heavy metals and metal-resistant bacteria in water and bottom sediments of the Straszyn reservoir (Poland)

    Science.gov (United States)

    Kulbat, Eliza; Sokołowska, Aleksandra

    2017-11-01

    The aim of this study is to investigate the distribution of selected heavy metals and metal-resistant bacteria in water and bottom sediments of the surface drinking water reservoir for Gdańsk. The following sequence of metals in regard to metal concentration in sediments can be written down: Zn > Pb > Cu > Cd. The evaluation of metals accumulation was performed using the Müller index, to indicate the bottom sediment's contamination and geochemical classification of sediment quality according to Polish standards. The Müller geochemical index was changing in a wide range: sediment is `strongly contaminated', in general the analysed bottom sediments were classified as the I and II category according to Polish geochemical standards. From the microbiological side a significant part of heterotrophic bacteria isolated from the bottom sediment and surface water (raw and treated water) showed a resistance to 0.2 mM and 2 mM concentrations of zinc, copper and lead. The highest percentages of metal-resistant bacteria were recorded in the sediments of the reservoir (60%-88%). The share of metal-resistant strains in the raw water was significantly lower (34%-61%). The results indicate also that water treatment processes may contribute to the selection of resistant strains.

  10. Survey of heavy metal pollution (copper, lead, zinc, cadmium, iron and manganese in drinking water resources of Nurabad city, Lorestan, Iran 2013

    Directory of Open Access Journals (Sweden)

    GHodratolah Shams Khorramabadi

    2016-09-01

    Full Text Available Background: Healthy water passes through the pipelines from supply resources to consuming places in which passing from these stages may cause some cases of contamination like heavy metal contamination. Therefore, the aim of this study was to evaluate the contamination of heavy metals (copper, lead, zinc, cadmium, iron, and manganese in water resources of Nurabad city of Lorestan in 2013. Materials and Methods: In this cross-sectional study, samples were collected from 7 wells of drinking water and 2 water storage tanks during 6 months in Nurabad. So that, heavy metal parameters such as copper, lead, zinc, cadmium, iron, and manganese were measured using an atomic absorption device and also electrical conductivity, sulfate, chloride and total dissolved solids were also measured in accordance with standard methods. Results: Results indicated that the concentration of studied metals in water sources was lower than the national standards and World Health Organization standard, and in the water supply system the concentration of some metals was more than standard level. Moreover, the results showed that the concentration of studied heavy metals were more in winter than in autumn. Conclusion: Generally, in the water resources of Nurabad city the concentration of studied heavy metals was lower than the national standards and World Health Organization standard and there are not problems for water consumers. However, due to public health and the presence of a high concentration of these metals in the distribution supply, the heavy metal concentration in drinking water of this region should be monitored regularly by responsible organizations.

  11. Evaluation of different buffered peptone water (BPW) based enrichment broths for detection of Gram-negative foodborne pathogens from various food matrices.

    Science.gov (United States)

    Margot, H; Zwietering, M H; Joosten, H; O'Mahony, Emer; Stephan, R

    2015-12-02

    This study evaluated the effects of changing the composition of the pre-enrichment medium buffered peptone water (BPW) on the growth of stressed and unstressed Gram-negative foodborne pathogens in a one-broth enrichment strategy. BPW supplemented with an available iron source and sodium pyruvate, along with low levels of 8-hydroxyquinoline and sodium deoxycholate (BPW-S) improved the recovery of desiccated Cronobacter spp. from powdered infant formula. Growth of Salmonella and STEC was comparable in all BPW variants tested for different food matrices. In products with high levels of Gram-negative background flora (e.g. sprouts), the target organisms could not be reliably detected by PCR in any of the BPW variants tested unless the initial level exceeded 10(3) cfu/10 g of sprouts. Based on these results we suggest BPW-S for a one-broth enrichment strategy of stressed Gram-negative foodborne pathogens from dry products. However, a one-broth enrichment strategy based on BPW variants tested in this evaluation is not recommended for produce with a high level of Gram-negative background flora due to very high detection limits. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Science.gov (United States)

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90–100% using a precipitation method with alkaline solution. PMID:22693485

  13. Evaluation of fuel fabrication and the back end of the fuel cycle for light-water- and heavy-water-cooled nuclear power reactors

    Energy Technology Data Exchange (ETDEWEB)

    Carter, W.L.; Olsen, A.R.

    1979-06-01

    The classification of water-cooled nuclear reactors offers a number of fuel cycles that present inherently low risk of weapons proliferation while making power available to the international community. Eight fuel cycles in light water reactor (LWR), heavy water reactor (HWR), and the spectral shift controlled reactor (SSCR) systems have been proposed to promote these objectives in the International Fuel Cycle Evaluation (INFCE) program. Each was examined in an effort to provide technical and economic data to INFCE on fuel fabrication, refabrication, and reprocessing for an initial comparison of alternate cycles. The fuel cycles include three once-through cycles that require only fresh fuel fabrication, shipping, and spent fuel storage; four cycles that utilize denatured uranium--thorium and require all recycle operations; and one cycle that considers the LWR--HWR tandem operation requiring refabrication but no reprocessing.

  14. Assessment of Mine Water Quality Using Heavy Metal Pollution Index in a Coal Mining Area of Damodar River Basin, India.

    Science.gov (United States)

    Mahato, Mukesh Kumar; Singh, Gurdeep; Singh, Prasoon Kumar; Singh, Abhay Kumar; Tiwari, Ashwani Kumar

    2017-07-01

    A total no. of 16 mine water (underground and opencast coal mine pump discharges) samples were collected from East Bokaro coalfield during pre-monsoon, monsoon and post-monsoon seasons. The concentrations of Fe, Mn, Cu, Pb, Zn, Ni, As, Se, Al, Cd and Cr were determined using inductively coupled plasma mass spectrometry for the assessment of spatio-temporal variations, source apportionment and heavy metal pollution indexing. The results demonstrated that concentrations of the metals showed significant seasonality and most variables exhibited higher levels in the pre-monsoon season. The principle component analysis for ionic source identification was synthesized into three factors with eigen values cut off at greater than unity and explained about 64.8% of the total variance. The extracted factors seemed to be associated to the geogenic, extensive mining and allied transportation sources of the elements. The heavy metal pollution index (HPI) of the mine water calculated for the individual locations varied from 7.1 to 49.5. Most of the locations fall under low to medium classes of HPI except few locations which are under the influence of surface mining and associated transportation.

  15. Concentration of selected heavy metals in water of the Juru River ...

    African Journals Online (AJOL)

    HP

    2012-04-24

    Apr 24, 2012 ... laboratory prior to the measurements and all in situ measurements were done during the high tide period. River water was sampled at one meter below the surface using. Van Dorn water sampler. Collected water samples were transferred into acid soaked teflon bottle (100 ml capacity) and acidified to pH 2.

  16. Organic matter and heavy metals in grey-water sludge | Eriksson ...

    African Journals Online (AJOL)

    In this study grey-water sludge originating from bathroom grey-water has been screened with respect to organic matter; particles; short-chain fatty alcohols and acids; selected metals and basic parameters as well as characterization of the organic matter content by oxygen utilization rate (OUR). The grey-water sludge ...

  17. Multivariate statistical evaluation of heavy metals in the surface water sources of Jia Bharali river basin, North Brahmaputra plain, India

    Science.gov (United States)

    Khound, Nayan J.; Bhattacharyya, Krishna G.

    2017-09-01

    The aim of this study was to assess the quality of surfacewater sources in the Jia Bharali river basin and adjoining areas of the Himalayan foothills with respect to heavy elements viz. (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) by hydrochemical and multivariate statistical techniques, such as cluster analysis (CA) and principal component analysis (PCA). This study presents the first ever systematic analysis on toxic elements of water samples collected from 35 different surface water sources in both the dry and wet seasons for a duration of 2 hydrological years (2009-2011). Varimax factors extracted by principal component analysis indicates anthropogenic (domestic and agricultural run-off) and geogenic influences on the trace elements. Hierarchical cluster analysis grouped 35 surfacewater sources into three statistically significant clusters based on the similarity of water quality characteristics. This study illustrates the usefulness of multivariate statistical techniques for analysis and interpretation of complex data sets, and in water quality assessment, identification of pollution sources/factors and understanding temporal/spatial variations in water quality for effective surfacewater quality management.

  18. Status of riverine soils, waters and sediments of a Mediterranean river catchment (the Turia river, Spain) regarding heavy metals potential contamination

    Science.gov (United States)

    Andreu, Vicente; Gimeno-García, Eugenia; Pascual-Aguilar, Juan Antonio

    2015-04-01

    One important source of freshwater to population are fluvial courses, but they receive contaminants by different ways, usually frorm wastewaters and difuse pollution. The fluvial sedimentary phase can act as resevoir that accumulate contaminants fixing them or allowing their decomposition or metabolization. However, environmental changes or human induced ones, could favour their release to the environment. In this work, seven heavy metals were monitored in soils, waters and sediments of the Turia River catchment. Along the river, 22 zones were selected for sampling according different lithologies, land uses, size of populations and the proximity to waste waters treatment plants (WWTPs), from the headwaters to the mouth. The selected metals (Cd, Co, Cr, Cu, Pb, Ni and Zn) were analysed to determine its total and extractable contents in soils, water and sediments. Total content of metals was extracted by microwave acid digestion and the extractable fraction in soils and sediments by treatment with EDTA. Atomic Absorption Spectrometry, using graphite furnace when necessary, was used for the determination of all metals. Metal values in waters are below the limits established by the EU legislation. As in waters, the sediments show highest values mainly in zones 10 and 22, close to urban areas, reaching values of 172.86 mg/kg for Pb, or 58.34 mg/kg for Cr. However, zone 2 near in the headwaters, and supposedly of reference for the River authorities, shows the highest values of zinc (96.96 mg/kg). Regarding the available/extractable fraction of the metals, the maximum values were observeg in zone 22 too, reching in the case of Pb 59.60 mg/kg. The percentage of available metal in the sediments of the studied zones vary between 15 and 40% for Cu, Pb and Zn, being the higher than 60% for Pb and Zn in zone 8 near the city of Teruel. In soils, the higest levels of total and extractable Cd, Co, Cr and Ni were determined in the zones 11 and 12, near the Benageber reservoir where

  19. Hydrocolloid liquid-core capsules for the removal of heavy-metal cations from water

    Energy Technology Data Exchange (ETDEWEB)

    Nussinovitch, A., E-mail: amos.nussi@mail.huji.ac.il; Dagan, O.

    2015-12-15

    Highlights: • Novel liquid-core capsules with a non-crosslinked alginate core were produced. • Capsules demonstrated highest efficiency adsorption of ∼300 mg Pb{sup 2+}/g alginate. • Regeneration was carried out by suspending capsules in 1 M HNO{sub 3} for 24 h. • Adsorption capacities of the capsules followed the order: Pb{sup 2+} > Cu{sup 2+} > Cd{sup 2+} > Ni{sup 2+}. - Abstract: Liquid-core capsules with a non-crosslinked alginate fluidic core surrounded by a gellan membrane were produced in a single step to investigate their ability to adsorb heavy metal cations. The liquid-core gellan–alginate capsules, produced by dropping alginate solution with magnesium cations into gellan solution, were extremely efficient at adsorbing lead cations (267 mg Pb{sup 2+}/g dry alginate) at 25 °C and pH 5.5. However, these capsules were very weak and brittle, and an external strengthening capsule was added by using magnesium cations. The membrane was then thinned with the surfactant lecithin, producing capsules with better adsorption attributes (316 mg Pb{sup +2}/g dry alginate vs. 267 mg Pb{sup +2}/g dry alginate without lecithin), most likely due to the thinner membrane and enhanced mass transfer. The capsules’ ability to adsorb other heavy-metal cations – copper (Cu{sup 2+}), cadmium (Cd{sup 2+}) and nickel (Ni{sup 2+}) – was tested. Adsorption efficiencies were 219, 197 and 65 mg/g, respectively, and were correlated with the cation’s affinity to alginate. Capsules with the sorbed heavy metals were regenerated by placing in a 1 M nitric acid suspension for 24 h. Capsules could undergo three regeneration cycles before becoming damaged.

  20. Inter- and intra-specific competition of duckweed under multiple heavy metal contaminated water.

    Science.gov (United States)

    Zhao, Zhao; Shi, Huijuan; Kang, Xianjiang; Liu, Cunqi; Chen, Lingci; Liang, Xiaofei; Jin, Lei

    2017-11-01

    The influences of intra- and inter-species competition on ecosystems are poorly understood. Lemna aequinoctialis and Spirodela polyrhiza were used to assess the effects of exposure to different concentrations of multiple heavy metals (copper-cadmium-zinc), when the plants were grown in mixed- or mono-culture. Parameters assessed included relative growth rate (RGR), content of chlorophyll, glutathione (GSH), malondialdehyde (MDA), as well as the activity of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD). Inter-specific competition was affected by metal concentration, with results indicating that inter-specific competition significantly affected duckweed growth and metal uptake in different heavy metal exposure conditions. Inter-specific competition increased growth rate of duckweed under high metal concentrations, although when compared with intra-specific competition, it caused no obvious differences under low metal concentrations. The growth of L. aequinoctialis was further increased in mixed culture when exposed to high metal concentrations, with inter-specific competition increasing the content of cadmium and zinc, while decreasing copper content of L. aequinoctialis compared with under intra-specific conditions. Conversely, inter-specific competition increased the content of copper and cadmium of S. polyrhiza, without causing obvious differences in zinc accumulation under high ambient concentrations. Under high metal conditions, inter-specific competition increased antioxidant enzyme activities in duckweed species, increasing resistance to heavy metals. Results show that inter-specific competition makes duckweed develop mechanisms to increase fitness and survival, such as enhancement of antioxidant enzyme activities, rather than limiting metal uptake when exposed to high concentrations of multiple metals. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Phytoremediation of Heavy Metal-Polluted Aquatic Ecosystem (Ologe Lagoon) By Water Hyacinth (Eichhornia crassipes [Mart.] Solms) and the Socio-Egological Implications

    Science.gov (United States)

    Ndimele, C. C.; Chukwuka, K. S.; Ndimele, P. E.

    2016-02-01

    The indiscriminate discharge of industrial effluents containing harmful substances such as heavy metals has become a global problem because of the negative effects of these substances on humans. Water hyacinth (Eichhornia crassipes) has been considered a menace since it entered Nigerian inland waters through neighbouring Republic of Benin in the 80's. Attempts to eradicate it has not been successful. Thus, the need to explore it useful potentials. It is used in paper production, feed formulation, phytoremediation etc. Phytoremediation is a bioremediation process that uses plants to remove, transfer, stabilize, and/or destroy pollutants in soil and water. The aim of the study was to investigate the phytoremediative potentials of water hyacinth resident in Ologe Lagoon as well as the socio-economic and ecological implications of their invasiveness. The study was conducted over a period of 18 months and 5 sampling stations were selected based on their proximity to the point of discharge of effluent, presence of water hyacinth and human activities. Water, sediment and water hyacinth samples were collected monthly from each sampling station and analysed for heavy metals (Cu, Fe, Pb, Zn, Cd, and As). Questionnaire was also administered for socio-economic impact assessment. The results showed that water hyacinth can absorb heavy metals from water even when the concentration of the metal in water is low. It was also discovered that water hyacinth invasion of Ologe Lagoon has adversely affected fishing, navigation, aesthetic and cultural values of the Lagoon.

  2. Electrospun alginate nanofibres as potential bio-sorption agent of heavy metals in water treatment

    CSIR Research Space (South Africa)

    Mokhena, Teboho C

    2017-03-01

    Full Text Available of researchers investigated nanofibre membranes as adsorbents of heavy metal ions from various sources [7-11]. Nanofibre membranes prepared by electrospinning are especially important due to their unique properties such as large surface area to volume ratio... solution is still a problem, and poly(ethylene oxide) PEO was therefore used to facilitate its spinnability. 2. Experimental 2.1 Materials Sodium alginate (SA) (Sigma, viscosity (25 °C, 2 wt% aqueous solution) = 2000 cP, medium viscosity, Mw...

  3. Evaluation of heavy metals level (arsenic, nickel, mercury and lead effecting on health in drinking water resource of Kohgiluyeh county using geographic information system (GIS

    Directory of Open Access Journals (Sweden)

    Abdolazim Alinejad

    2016-08-01

    Full Text Available This study was conducted to determine the amount of heavy metals (Arsenic, Nickel, Mercury, and Lead in drinking water resource of Kohgiluyeh County using Geographic Information System (GIS. This cross-sectional study was conducted on drinking water resource of Kohgiluyeh County (33 water supplies and 4 heavy metals in 2013. 264 samples were analyzed in this study. The experiments were performed at the laboratory of Water and Wastewater Company based on Standard Method. The Atomic Adsorption was used to evaluate the amount of heavy metals. The results were mapping by Geographic Information System software (GIS 9.3 after processing of parameters. Finally, the data were analyzed by SPSS 16 and Excel 2007. The maximum amount of each heavy metal and its resource were shown as follow: Nickel or Ni (Source of w12, 124ppb, Arsenic or As (w33, 42 ppb, Mercury or Hg (w22 and w30, 96ppb, Lead or Pb (w21, 1553ppb. Also, the GIS maps showed that Lead in the central region was very high, Mercury and Arsenic in the northern region were high and Nickel in the eastern and western regions was high. The Kriging method and Gauss model were introduced as best method for interpolation of these metals. Since the concentration of these heavy metals was higher than standard levels in most drinking water supplies in Kohgiluyeh County and these high levels of heavy metals can cause the adverse effects on human health; therefore, the environmental and geological studies are necessary to identify the pollution resource and elimination and removal of heavy metals

  4. Ecological risk assessment of toxic organic pollutant and heavy metals in water and sediment from a landscape lake in Tianjin City, China.

    Science.gov (United States)

    Zhang, Ying; Liu, Yuanyuan; Niu, Zhiguang; Jin, Shaopei

    2017-05-01

    To estimate the ecological risk of toxic organic pollutant (formaldehyde) and heavy metals (mercury (Hg), arsenic (As), cadmium (Cd), and chromium (Cr)) in water and sediment from a landscape Lake in Tianjin City, an ecological risk assessment was performed. The risk quotient (RQ) method and the AQUATOX model were used to assess the ecological risk of formaldehyde in landscape water. Meanwhile, the RQ method and the potential ecological risk index method were used to assess the ecological risk of four heavy metals in water and sediment from the studied landscape lake, respectively. The results revealed that the maximum concentration of formaldehyde in landscape water was lower than the environmental quality standards of surface water in China. The maximum simulated concentrations of formaldehyde in phytoplankton and invertebrates were 3.15 and 22.91 μg/L, respectively, which were far less than its toxicity data values (1000 and 510 μg/L, respectively), suggesting that formaldehyde in landscape water was at a safe level for aquatic organisms. The RQ model indicated that the risks of phytoplankton and invertebrates were higher than that of fish posed by Hg and Cd in landscape water, and the risks from As and Cr were acceptable for all test organisms. Cd is the most important pollution factor among all heavy metals in sediment from studied landscape lake, and the pollution factor sequence of heavy metals was Hg > As > Cr > Cd. The values of risk index (RI) for four heavy metals in samples a and b were 43.48 and 72.66, which were much lower than the threshold value (150), suggesting that the ecological risk posed by heavy metals in sediment was negligible.

  5. Incidence and interactions of heavy metals and pharmaceutical products in surface waters of a Mediterranean coastal wetland.

    Science.gov (United States)

    Andreu, Vicente; Pascual, Juan Antonio; Gimeno, Eugenia; Picó, Yolanda

    2013-04-01

    Heavy metals have been during decades a result of the human fingerprint on the ecosystems, mainly in waters, soils or vegetation, being considered as a major s threat also on human health. However, the increasing in human population shows other aspect, such as the so called "emerging contaminants". They constitute an increasing group of compounds that includes, among others, personal care products, drugs of abuse and pharmaceuticals. These contaminants have become, in recent years, of great concern for researchers and, even, for the population. Among these substances, the presence of pharmaceuticals in the ecosystems compartments has becoming an increasing problem for environmental sustainability, and also for human health, with consequences very scarcely known. They reach the nature from waste waters treatment plants, industrial waste effluents, uncontrolled landfills, etc. affecting particularly the fauna in its different levels. Some pharmaceuticals have shown toxicity not only to bacteria, algae and invertebrates but also to fish, mollusks, etc. This work is focused on the study of the presence of 17 relevant pharmaceuticals and 7 heavy metals (Cd, Co, Cr, Cu, Ni, Pb and Zn) in surface waters of the irrigation channels and the lagoon of the Pego-Oliva Marsh Natural Park (Valencian Community, Spain), which is characterized by a long history of human pressures, such as marsh transformation for agricultural uses, urbanization, etc. In this area, 34 sampling zones were selected, covering the main land uses. The interactions and possible relationships between both groups of contaminants were studied, together with the influences of the source of water samples, land uses and their spatial distribution. All water samples appeared contaminated with at least with two compounds. Ibuprofen and codeine were the compounds more frequently detected in concentrations between detection limit and a maximum of 59 ng/L and 63 ng/L respectively. Regarding the studied metals, Zn

  6. Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection

    Directory of Open Access Journals (Sweden)

    Zoll J

    2015-07-01

    Full Text Available Joffrey Zoll,1 Jamal Bouitbir,1 Pascal Sirvent,2 Alexis Klein,3 Antoine Charton,1,4 Liliana Jimenez,3 François R Péronnet,5 Bernard Geny,1 Ruddy Richard61Physiology Department, Faculty of Medicine and EA3072, Université de Strasbourg, Strasbourg, 2Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l’Exercice en Conditions Physiologiques et Pathologiques, Clermont-Ferrand, 3Danone Research, Centre Daniel Carasso, Palaiseau, 4Department of Anesthesia and Critical Care and EA3072, Hôpital de Hautepierre, Université de Strasbourg, France; 5Kinesiology Department, Université de Montréal, Montréal, QC, Canada; 6Department of Sport Medicine and Functional Explorations and INRA UMR 1019, Faculty of Medicine, Université d’Auvergne, Clermont-Ferrand, FranceBackground: It has been suggested that oxygen (O2 diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates, which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients.Materials and methods: Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1 at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg, with glutamate–malate or N, N, N', N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD–ascorbate (with antimycin A as substrates; and 2 at increasing adenosine diphosphate (ADP concentration with glutamate–malate as substrate.Results: As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate–malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD–ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was

  7. Heavy metal removal from produced water using retorted shale; Remocao de metais pesados em aguas produzidas utilizando xisto retortado

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel, Patricia M.; Melo, Marcos A.F.; Melo, Dulce M.A.; Silva Junior, Carlos N.; Assuncao, Ary L.C. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Anjos, Marcelino J. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    2004-07-01

    The Production of oil and gas is usually accompanied by the production of large volume of water that can have significant environmental effects if not properly treated. In this work, the use of retort shale was investigated as adsorbent agent to remove heavy metals in produced water. Batch adsorption studies in synthetic solution were performed for several metal ions. The efficiency removal was controlled by solution pH, adsorbent dosage, and initial ion concentration and agitation times. Two simple kinetic models were used, pseudo-first- and second-order, were tested to investigate the adsorption mechanisms. The equilibrium data fitted well with Langmuir and Freundlich models. The produced water samples were treated by retorted shale under optimum adsorption conditions. Synchrotron radiation total reflection X-ray fluorescence was used to analyze the elements present in produced water samples from oil field in Rio Grande do Norte, Brazil. The removal was found to be approximately 20-50% for Co, Ni, Sr and above 80% for Cr, Ba, Hg and Pb. (author)

  8. Arsenic and heavy metals contamination, risk assessment and their source in drinking water of the Mardan District, Khyber Pakhtunkhwa, Pakistan.

    Science.gov (United States)

    Gul, Nida; Shah, Mohammad Tahir; Khan, Sardar; Khattak, Nimat Ullah; Muhammad, Said

    2015-12-01

    The present study was conducted to investigate the physico-chemical characteristics in drinking water of Mardan District, Pakistan. Furthermore, water quality was evaluated for the risk assessment of arsenic and heavy metals (HMs) and their contamination sources. Representative groundwater samples of shallow and deep sources were collected in the study area. These samples were analyzed for physical parameters, anions, light metals (LMs) and HMs. Results were compared with the drinking water guideline values set by the World Health Organization and the US Environmental Protection Agency. Average concentrations of anions, LMs and HMs were found within the maximum allowable contaminant levels except for bicarbonates, Fe, Cu, and Pb. Results revealed that hazard quotients >1 were observed for shallow groundwater for 10% samples only, suggesting potential health risk from water consumption. Correlation analysis and principal component analysis showed a relationship among various physico-chemical parameters in both shallow and deep groundwater. Statistical analyses suggested the geogenic and anthropogenic sources for possible enhancement of various physico-chemical parameters in the aquifer system of the study area.

  9. Biomarkers of oxidative stress in rat for assessing toxicological effects of heavy metal pollution in river water.

    Science.gov (United States)

    Reddy, Utkarsh A; Prabhakar, P V; Rao, G Sankara; Rao, Pasham Rajasekhar; Sandeep, K; Rahman, M F; Kumari, S Indu; Grover, Paramjit; Khan, Haseeb A; Mahboob, M

    2015-09-01

    Increasing use of heavy metals in various fields, their environmental persistency, and poor regulatory efforts have significantly increased their fraction in river water. We studied the effect of Musi river water pollution on oxidative stress biomarkers and histopathology in rat after 28 days repeated oral treatment. River water analysis showed the presence of Zn and Pb at mg/l concentration and Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Sn, and Sb at μg/l concentration. River water treatment resulted in a dose-dependent accumulation of metals in rat organs, being more in liver followed by kidney and brain. Metal content in both control and low-dose group rat organs was below limit of detection. However, metal bioaccumulation in high- and medium-dose group organs as follows: liver-Zn (21.4 & 14.5 μg/g), Cu (8.3 & 3.6 μg/g), and Pb (8.2 & 0.4 μg/g); kidney-Zn (16.2 & 7.9 μg/g), Cu (3.5 & 1.4 μg/g), Mn (2.9 & 0.5 μg/g), and Pb (2.6 & 0.5 μg/g); and brain-Zn (2.4 & 1.1 μg/g), and Ni (1 & 0.3 μg/g). These metals were present at high concentrations in respective organs than other metals. The increased heavy metal concentration in treated rat resulted significant increase in superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione S transferase enzymes activity, and lipid peroxidation in a dose-dependent manner. However, glutathione content and catalase activity were significantly decreased in treated rat organs. Histopathological examination also confirmed morphological changes in rat organs due to polluted river water treatment. In conclusion, the findings of this study clearly indicate the oxidative stress condition in rat organs due to repeated oral treatment of polluted Musi river water.

  10. Ecological risk assessment of a coastal zone in Southern Vietnam: Spatial distribution and content of heavy metals in water and surface sediments of the Thi Vai Estuary and Can Gio Mangrove Forest.

    Science.gov (United States)

    Costa-Böddeker, Sandra; Hoelzmann, Philipp; Thuyên, Lê Xuân; Huy, Hoang Duc; Nguyen, Hoang Anh; Richter, Otto; Schwalb, Antje

    2017-01-30

    Enrichment of heavy metals was assessed in the Thi Vai Estuary and in the Can Gio Mangrove Forest (SE, Vietnam). Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn contents in water and in sediments were measured. Total organic carbon, nitrogen, phosphorus and C/N ratios were determined. Cu and Cr values were higher than threshold effect level of toxicity, while Ni exceeded probable effect level, indicating the risk of probable toxicity effects. Enrichment factors (EF), contamination factor (CF) and Geo-accumulation index (I-geo) were determined. CF reveals moderate to considerable pollution with Cr and Ni. EF suggests anthropogenic sources of Cr, Cu and Ni. I-geo indicates low contamination with Co, Cu and Zn and moderate contamination with Cr and Ni. Overall metal contents were lower than expected for this highly industrialized region, probably due to dilution, suggesting that erosion rates and hydrodynamics may also play a role in metal contents distribution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Purification by ozonolysis of {sup 18}O enriched water after cyclotron irradiation and the utilization of the purified water for the production of [{sup 18}F]-FDG (2-deoxy-2-[{sup 18}F]-fluoro-D-glucose)

    Energy Technology Data Exchange (ETDEWEB)

    Asti, M. [Nuclear Medicine Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Grassi, E. [Medical Physics Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Sghedoni, R. [Medical Physics Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy)]. E-mail: roberto.sghedoni@asmn.re.it; De Pietri, G. [Nuclear Medicine Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Fioroni, F. [Medical Physics Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Versari, A. [Nuclear Medicine Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Borasi, G. [Medical Physics Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy); Salvo, D. [Nuclear Medicine Department, Santa Maria Nuova Hospital via Risorgimento 80, 42100 Reggio Emilia (Italy)

    2007-07-15

    The high cost of virgin {sup 18}O-enriched water has forced many researchers to study methods to purify and recycle enriched water after the first irradiation for the production of radiopharmaceuticals. In our study, [{sup 18}O]H{sub 2}O was purified by ozonolysis and distillation. Analyses showed a large decrease in impurities after this treatment. The purification procedure was carried out after the production of 94 batches of [{sup 18}F]-FDG, which were manufactured using a GE Minitrace cyclotron and a GE Mx TracerLab synthesizer. Saturation yields after bombardment, using virgin and re-purified water were, respectively, 2864{+-}204 MBq/{mu}A and 2727{+-}167 MBq/{mu}A, a decrease of 5.5%. The decrease in [{sup 18}F]-FDG yield, from 67.2{+-}0.7% to 65.5{+-}0.9%, can be ascribed to the irradiation step only.

  12. Distribution characteristics and ecological risk assessment of toxic heavy metals and metalloid in surface water of lakes in Daqing Heilongjiang Province, China.

    Science.gov (United States)

    Wang, Xiaodi; Zang, Shuying

    2014-05-01

    It is necessary to estimate heavy metal concentrations and risk in surface water for understanding the heavy metal contaminations and for sustainable protection of ecosystems and human health. To investigate the anthropogenic contribution of heavy metal accumulation surrounding an industrial city in China, the concentrations of six heavy metals, including mercury (Hg), arsenic (As), chromium (Cr), lead (Pb), copper (Cu), and cadmium (Cd) were examined; from four different regions of Daqing in autumn 2011 and winter 2012. The results showed heavy metals distributed in the industrial area at concentrations relatively higher than those in other three areas, while concentrations in the farming area and the protected area were lower. The heavy metal concentrations of water bodies in all areas, except those for Hg and As, Cu, Pb and Cr were lower than the cutoff values for the Class I water quality that was set as the highest standard to protect the national nature reserves. While Hg and As of lakes in industry region had a higher level than those in the agriculture and landscape water, the lowest allowed. The concentrations of all the heavy metals in winter were higher than in the autumn. Cu had a higher ecological risks level to freshwater organisms. The discharge of urban sewage and industrial wastewater might be a major pollutant source, thus these sources should identified before remediation efforts. Efforts are needed to protect the lakes from pollution and also to reduce environmental health risks. This study and the valuable data will pave the way for future research on these Lakes in Daqing.

  13. Dually Prewetted Underwater Superoleophobic and under Oil Superhydrophobic Fabric for Successive Separation of Light Oil/Water/Heavy Oil Three-Phase Mixtures.

    Science.gov (United States)

    Cao, Guoliang; Zhang, Wenbo; Jia, Zhen; Liu, Feng; Yang, Haiyue; Yu, Qianqian; Wang, Yazhou; Di, Xin; Wang, Chengyu; Ho, Shih-Hsin

    2017-10-18

    Remediation of oil spills requires new technologies to separate light oil/water/heavy oil mixtures. Low-cost, biological, and environmentally friendly materials are needed to treat water pollution caused by oils. In this study, a corn straw powder (CSP)-coated fabric (CSPF) was fabricated by spraying waste CSP and polyurethane onto amphiphilic cotton fabric, and thus, the wettability of CSPF is enhanced by taking advantage of the hierarchical structure and increased surface roughness. Therefore, the CSPF could be dually prewetted (DCSPF) with both water and oil, and it showed underwater superoleophobic and under oil superhydrophobic properties without any further chemical modification. When applied to light oil/water/heavy oil separation, the DCSPF could be used to successively separate light oil/water/heavy oil three-phase mixtures under gravity with a high separation efficiency and flux. In addition, the DCSPF showed excellent structural and chemical stability according to repeated cycling and corrosive solution/oil separation experiments. The results of this study are of value in providing a simple, low-cost, and environment-friendly approach for application in the field of successive separation of light oil/water/heavy oil three-phase mixtures.

  14. Effects of Hyporheic Water Fluxes and Sediment Grain Size on the Concentration and Diffusive Flux of Heavy Metals in the Streambed.

    Science.gov (United States)

    Liu, Qi; Song, Jinxi; Zhang, Guotao; Wang, Weize; Guo, Weiqiang; Tang, Bin; Kong, Feihe; Huo, Aidi

    2017-09-06

    The hyporheic zone regulates physicochemical processes in surface-groundwater systems and can be an important source of heavy metals in fluvial systems. This study assesses the pore water concentrations and diffusive fluxes of heavy metals with respect to the vertical water exchange flux (VWEF) and sediment grain size. Water and sediment samples were collected on August 2016 from upstream Site 1 and downstream Site 2 along the Juehe River in Shaanxi Province, China. Streambed vertical hydraulic conductivity (Kv) and the VWEF were estimated via the standpipe permeameter test method and Darcy's law. The heavy metal concentrations in the pore water were measured and the diffusive fluxes were calculated using Fick's first law. The VWEF patterns were dominated by upward flow, and Site 1 featured higher values of Kv and VWEF. Higher Cu and Zn concentrations occurred near the channel centre with coarse sand and gravel and greater upward VWEFs because coarser sediment and greater upward VWEFs cause stronger metal desorption capacity. Additionally, Cu and Zn at the two sites generally diffused from pore water to surface water, potentially due to the upward VWEF. The VWEF and sediment grain size are likely crucial factors influencing the heavy metal concentrations and diffusive fluxes.

  15. Heavy Metal Coprecipitation with Hydrozincite [Zn5(CO3)2(OH)6] from Mine Waters Caused by Photosynthetic Microorganisms

    Science.gov (United States)

    Podda, Francesca; Zuddas, Paola; Minacci, Andrea; Pepi, Milva; Baldi, Franco

    2000-01-01

    An iron-poor stream of nearly neutral pH polluted by mine tailings has been investigated for a natural phenomenon responsible for the polishing of heavy metals in mine wastewaters. A white mineralized mat, which was determined to be hydrozincite [Zn5(CO3)2(OH)6] by X-ray diffraction analysis, was observed in the stream sediments mainly in spring. The precipitate shows a total organic matter residue of 10% dry weight and contains high concentrations of Pb, Cd, Ni, Cu, and other metals. Scanning electron microscopy analysis suggests that hydrozincite is mainly of biological origin. Dormant photosynthetic microorganisms have been retrieved from 1-year-old dry hydrozincite. The autofluorescent microorganisms were imaged by a scanning confocal laser microscope. A photosynthetic filamentous bacterium, classified as Scytonema sp. strain ING-1, was found associated with microalga Chlorella sp. strain SA1. This microbial community is responsible for the natural polishing of heavy metals in the water stream by coprecipitation with hydrozincite. PMID:11055969

  16. Biosorption Of Heavy Metals From Mining Influenced Water Onto Chitin Products

    Science.gov (United States)

    Mining influenced water (MIW) emanating from mine sites poses a major environmental concern due to its impact on water contamination caused by low pH and the presence of high concentrations of toxic metals. Chitorem SC-20® (raw crushed crab shells containing 40% w/w C...

  17. Heavy metal content in fish and water from River Niger at ...

    African Journals Online (AJOL)

    user

    The concentrations of Lead (Pb), Copper (Cu), Cadmium (Cd) and Zinc (Zn) in fish and water from River. Niger at Agenebode, Nigeria were .... 696 series) equipped with solar software using air acetylene flame. Concentrations of metals in water and ..... sourced from batteries, fossil fuel, fertilizers, plastics, alloys and paints.

  18. Biosorption of heavy metals in polluted water, using different waste fruit cortex

    Science.gov (United States)

    Kelly-Vargas, Kevin; Cerro-Lopez, Monica; Reyna-Tellez, Silvia; Bandala, Erick R.; Sanchez-Salas, Jose Luis

    The biosorption capacity of different cortex fruit wastes including banana (Musa paradisiaca), lemon (Citrus limonum) and orange (Citrus sinensis) peel were evaluated. In order to perform these experiments, grinded dried cortexes were used as package in 100 mm high, 10 mm i.d. columns. The grinded material was powdered in a mortar and passed through a screen in order to get two different particle sizes, 2 and 1 mm, for all powders. To estimate the biosorption capabilities of the tested materials, different heavy metals were passed through the columns and the elution filtrate reloaded different times to increase the retention of metals. The heavy metals used were prepared as synthetic samples at 10 mg/L of Pb(NO3)2, Cd(NO3)2, and Cu(NO3)2·6H2O using primary standards. In preliminary experiments using banana cortex, it was found that material with 1 mm of particle size showed higher retention capability (up to12%) than the material with 2 mm of particle size. Considering these results, 1 mm particle size material was used in further experiments with the other waste materials. It was found that for Pb and Cu removal, lemon and orange cortex showed better biosorption capability when compared with banana cortex (up to 15% less for Pb and 48% less for Cu). For Cd, banana cortex showed better biosorption capability 57% (67.2 mg/g of cortex) more than orange (28.8 mg/g of cortex), and 82% more than lemon (12 mg/g of cortex). Reload of the columns with the filtrate after passing through the column improved the removal capability of all the materials tested from 10% to 50% depending on the cortex and metal tested.

  19. The ecological effects of water level fluctuation and phosphate enrichment in mesotrophic peatlands are strongly mediated by soil chemistry

    NARCIS (Netherlands)

    Mettrop, I.S.; Rutte, M.D.; Kooijman, A.M.; Lamers, L.P.M.

    2015-01-01

    Since the re-establishment of a more natural water regime is considered by water management in wetlands with artificially stable water levels, the biogeochemical and ecological effects of water level fluctuation with different nutrient loads should be investigated. This is particularly important for

  20. Detection of heavy metals released at the sediment/water interface by combining Anodic Stripping Voltammetry (ASV) and Scanning Electrochemical Microscopy (SECM) measurements

    Science.gov (United States)

    Daniele, S.; Ciani, I.; Bragato, C.; Baldo, M. A.

    2003-05-01

    Hemisphere mercury microelectrodes are investigated in combine anodic stripping voltammetry (ASV) and scanning electrochemical microscopy (SECM) experiments for the detection of heavy metal ions at the solid/solution interface of a sediment sample. Relatively large anodic stripping peaks due to lead are monitored at μm distances from the solid particles, while, under the same experimental conditions, no or lower ASV peaks are found in the bulk solution. This suggests that diffusion gradients at sediment/water interface is monitored. This method, therefore, offers a new possibility for investigating on spatial differences of immobilization and remobilization processes of heavy metals at sediment/water interfaces.

  1. Numerical Analysis on the Calandria Tubes in the Moderator of a Heavy Water Reactor Using OpenFOAM and Other Codes

    Science.gov (United States)

    Chang, Se-Myong; Kim, Hyoung Tae

    2014-06-01

    CANDU, a prototype of heavy water reactor is modeled for the moderator system with porous media buoyancy-effect heat-transfer turbulence model. OpenFOAM, a set of C++ classes and libraries developed under the object-oriented concept, is selected as the tool of numerical analysis. The result from this computational code is compared with experiments and other commercial code data through ANSYS-CFX and COMSOL Multi-physics. The three-dimensional code concerning buoyancy force, turbulence, and heat transfer is tested and shown to be successful for the analysis of thermo-hydraulic system of heavy water reactors.

  2. Rhizofiltration of Heavy Metals (Cadmium, Lead and Zinc From Fly Ash Leachates Using Water Hyacinth (Eichhornia Crassipes

    Directory of Open Access Journals (Sweden)

    Amit Kumar Yadav

    2015-02-01

    Full Text Available Fly ashes are usually contaminated with toxic heavy metals. These metals are leaching out aftercontact with water during wet disposal system, thus polluting the soil, surface and groundwater. In the present study, a hydroponics experiment was conducted to examine the removalof heavy metals Cd, Pb and Zn by Eichhornia crassipes grown at various concentration of fly ash ranging from 10, 20 and 40 percent over a period of 30 days.After 30 days, the plants were separately harvested, dried and weighedfor biomass of the roots and shoots. The uptake of each metalwas studied in the root and shoot separately, to determine the bioaccumulation of metals in Eichhornia crasspies.The translocation factor was calculated to study the efficiency of the plants forbioaccumulation of each metal in roots and shoot. The results showed that maximum uptake of metals Cd, Pb and Zn by plantwasfoundat the higher concentration (40% of fly ash.The metals uptake found was 99.16, 166.52 and 741.04 μg g-1 tissues in the roots, respectively and 33.46, 41.33 and 255.90 μgg-1 tissues in the shoots, respectively and successfullyremoved up to 78% of Cd, 82% of Pb and 70% of Zn.The maximum removal efficiency by plant for Cd, Pb and Zn at lower concentration (10% of fly ash was 84%, 86% and 75%, respectively.The heavy metals accumulated more in roots than in the shoots by Eichhornia crassipes. The maximum bioconcentration factor and translocation factor value of Eichhornia crappies for Cd, Pb and Zn were calculated as 705.55, 705.55 and 614.51 and 41.86, 47.18 and 34.53 respectively. The high removal efficiencies of heavy metals Cd, Pb and Zn was find without toxic effect by this aquatic macrophyte, thisplant can be recommended for the actual treatment of fly ash leachatesin ash pond to clean up the aquatic environment.DOI: http://dx.doi.org/10.3126/ije.v4i1.12187International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page : 179-196   

  3. Perspectives of phytoremediation using water hyacinth for removal of heavy metals, organic and inorganic pollutants in wastewater.

    Science.gov (United States)

    Rezania, Shahabaldin; Ponraj, Mohanadoss; Talaiekhozani, Amirreza; Mohamad, Shaza Eva; Md Din, Mohd Fadhil; Taib, Shazwin Mat; Sabbagh, Farzaneh; Sairan, Fadzlin Md

    2015-11-01

    The development of eco-friendly and efficient technologies for treating wastewater is one of the attractive research area. Phytoremediation is considered to be a possible method for the removal of pollutants present in wastewater and recognized as a better green remediation technology. Nowadays the focus is to look for a sustainable approach in developing wastewater treatment capability. Water hyacinth is one of the ancient technology that has been still used in the modern era. Although, many papers in relation to wastewater treatment using water hyacinth have been published, recently removal of organic, inorganic and heavy metal have not been reviewed extensively. The main objective of this paper is to review the possibility of using water hyacinth for the removal of pollutants present in different types of wastewater. Water hyacinth is although reported to be as one of the most problematic plants worldwide due to its uncontrollable growth in water bodies but its quest for nutrient absorption has provided way for its usage in phytoremediation, along with the combination of herbicidal control, integratated biological control and watershed management controlling nutrient supply to control its growth. Moreover as a part of solving wastewater treatment problems in urban or industrial areas using this plant, a large number of useful byproducts can be developed like animal and fish feed, power plant energy (briquette), ethanol, biogas, composting and fiber board making. In focus to the future aspects of phytoremediation, the utilization of invasive plants in pollution abatement phytotechnologies can certainly assist for their sustainable management in treating waste water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae, of Cross River, Nigeria

    Directory of Open Access Journals (Sweden)

    Ezekiel Olatunji Ayotunde

    2012-09-01

    Full Text Available Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I, Obubra Ogada (Station II and Calabar (Station III were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus (29.4-39.5cm SL, 310-510g, sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles of Zn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS. In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297±0.022 μg/g, Cadmium (0.011±0.007μg/g, Iron (0.371±0.489μg/g, Lead (0.008±0.008μg/g, were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009±0.00μg/g, Copper (0.015±0.01 μg/g, Lead (0.0002±0.00μg/g Cadmium (0.0006±0.001μg/g, Zinc (0.0036±0.003μg/g, were observed in the surface water, respectively. The highest mean concentration of Copper (0.037±0.03μg/g, Iron (0.053±0.04μg/g, Lead (0.0002±0.00μg/g, Cobalt (0.0002±0.00μg/g, Cadmium (0.0006±0.001μg/g and Zinc (.009±0.0015μg/g was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057±0.04μg/g, 0.043±0.03μg/g, 0.0006±0.00μg/g, 0.0002±0.00μg/g, 0.0009±0.00μg/g, 0.099±0.00404μg/g in Iron, Copper, Lead, Cobalt, Cadmium and Zinc were observed in the sediment, respectively; Chromium was not detected in the sediment for the whole

  5. Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae), of Cross River, Nigeria.

    Science.gov (United States)

    Ayotunde, Ezekiel Olatunji; Offem, Benedict Obeten; Ada, Fidelis Bekeh

    2012-09-01

    Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I), Obubra Ogada (Station II) and Calabar (Station III) were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus) (29.4-39.5cm SL, 310-510g), sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles ofZn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS). In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297 +/- 0.022 microg/g), Cadmium (0.011 +/- 0.007 microg/g), Iron (0.371 +/- 0.489 microg/g), Lead (0.008 +/- 0.008 microg/g), were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009 +/- 0.00) microg/g), Copper (0.015 +/- 0.01 microg/g), Lead (0.0002 +/- 0.00 microg/g) Cadmium (0.0006 +/- 0.001 microg/g), Zinc (0.0036 +/- 0.003 microg/g), were observed in the surface water, respectively. The highest mean concentration of Copper (0.037 +/- 0.03 microg/g), Iron (0.053 +/- 0.04 microg/g), Lead (0.0002 +/- 0.00 microg/g), Cobalt (0.0002 +/- 0.00 microg/g), Cadmium (0.0006 +/- 0.001 microg/g) and Zinc (.009 +/- 0.0015 microg/g) was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057 +/- 0.04 microg/g, 0.043 +/- 0.03 microg/g, 0.0006 +/- 0.00 microg/g, 0.0002 +/- 0.00 microg/g, 0.0009 +/- 0.00 microg/g, 0.099 +/- 0.00404 microg/g in Iron

  6. Investigating the Concentration of Heavy Metals in Bottled Water and Comparing with its Standard: Case Study

    Directory of Open Access Journals (Sweden)

    Mohammad Hossien Salmani

    2017-09-01

    Results: Brand No. 1, the concentration of zinc ion was larger in Brand 2 while in Brand No. 2 had larger copper, nickel, and aluminum ions. The results indicated that the concentration of the measured metal ions were below the allowable limit of drinking water standard across all of the studied samples. Conclusion: Based on the obtained results from the investigated parameters, it can be concluded that the bottled water of both brands poses no health issue and is drinkable. Considering the changes in the concentration of ions and the increasing trend of consumption of bottled waters, their monitoring and qualitative control of pollutants are very crucial in terms of public health.

  7. Combined effects of CO2 enrichment, diurnal light levels and water stress on foliar metabolites of potato plants grown in naturally sunlit controlled environment chambers.

    Science.gov (United States)

    Barnaby, Jinyoung Y; Fleisher, David; Reddy, Vangimalla; Sicher, Richard

    2015-02-01

    Experiments were conducted in outdoor, naturally sunlit, soil-plant-atmosphere research (SPAR) chambers using plants grown in pots. Drought treatments were imposed on potato plants (Solanum tuberosum cv. Kennebec) beginning 10 days after tuber initiation. A total of 23 out of 37 foliar metabolites were affected by drought when measured 11 days after initiating water stress treatments. Compounds that accumulated in response to drought were hexoses, polyols, branched chain amino acids (BCAAs) and aromatic amino acids, such as proline. Conversely, leaf starch, alanine, aspartate and several organic acids involved in respiratory metabolism decreased with drought. Depending upon harvest date, a maximum of 12 and 17 foliar metabolites also responded to either CO2 enrichment or diurnal treatments, respectively. In addition, about 20% of the measured metabolites in potato leaflets were simultaneously affected by drought, CO2 enrichment and diurnal factors combined. This group contained BCAAs, hexoses, leaf starch and malate. Polyols and proline accumulated in response to water stress but did not vary diurnally. Water stress also amplified diurnal variations of hexoses and starch in comparison to control samples. Consequently, specific drought responsive metabolites in potato leaflets were dramatically affected by daily changes of photosynthetic carbon metabolism. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  8. Phase I enzyme induction in Girardinichthys viviparus, an endangered goodeid fish, exposed to water from native localities enriched with polychlorinated biphenyls.

    Science.gov (United States)

    Vega-López, Armando; Jiménez-Orozco, F Alejandro; Jiménez-Zamudio, Luís A; García-Latorre, Ethel; Domínguez-López, M Lilia

    2009-10-01

    The present study examines the induction of mixed-function oxidase (MFO) enzymes, including CYP content CYP1A (EROD) activity and alcohol dehydrogenase activity (ADH), in an endemic Mexican fish species, the black-fin goodeid Girardinichthys viviparus, exposed to the water of two localities, Lake Texcoco (LTX) and Lake Zumpango, and to the same matrices enriched in polychlorinated biphenyls (PCBs) to simulate the potential toxic effects of sublethal increases in these xenobiotics. Fishes of both sexes born in the laboratory were exposed for 1, 2, 4, 8, and 16 days. Water from the two types of localities of the black-fin goodeid contains MFO inducers. Of the two, the most contaminated is LTX water, which also contains PCBs. EROD activity was higher in all treatments with female compared with male fish. This suggests greater metabolic compromise in female fish as a response to damage caused by these xenobiotics. In this species, CYP induction displayed two patterns that were not always concurrent with higher CYP1A activity. In the enriched matrix system, biotransformation processes were notably altered. Increased ADH may indicate that this enzyme is involved in the biotransformation of PCBs and their metabolites, particularly in male fish, and provides at least a part of reductive power required by the MFO enzymes; however, specific studies are needed to clarify this point.

  9. One-step enrichment and chemiluminescence detection of sodium dodecyl benzene sulfonate in river water using Mg-Al-carbonate layered double hydroxides.

    Science.gov (United States)

    Guan, Weijiang; Zhou, Wenjuan; Han, Dongmei; Zhang, Mengchun; Lu, Chao; Lin, Jin-Ming

    2014-03-01

    In this work, Mg-Al CO3-layered double hydroxides (LDHs) were used as adsorbent materials for sodium dodecyl benzene sulfonate (SDBS) in aqueous solutions, the enriched SDBS can be directly detected by IO4(-)-H2O2 chemiluminescence (CL) system. The commonly existing cations cannot be enriched by Mg-Al CO3-LDHs due to the structurally positively charged layers of LDHs, while other adsorbed anionic interferents had no effect on the IO4(-)-H2O2 CL reaction. The corresponding linear regression equation was established in the range of 0.1-10 μM for SDBS. The detection limit at a signal-to-noise (S/N) ratio of 3 for SDBS was 0.08 μM. The relative standard deviation (RSD) for nine repeated measurements of 0.5 μM SDBS was 2.6%. This proposed method has been successfully applied to the determination of SDBS in river water samples. To the best of our knowledge, we have first time coupled the high enrichment capacity of LDHs towards anions with CL detection for analytes. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Assessment of heavy metals (Cd, Cr and Pb) in water, sediment and seaweed (Ulva lactuca) in the Pulicat Lake, South East India.

    Science.gov (United States)

    Kamala-Kannan, Seralathan; Prabhu Dass Batvari, B; Lee, Kui Jae; Kannan, N; Krishnamoorthy, R; Shanthi, K; Jayaprakash, M

    2008-04-01

    The concentrations of three heavy metals chromium (Cr), cadmium (Cd) and lead (Pb) were examined in water, sediment and green algae (Ulva lactuca); collected from six different stations at Pulicat Lake, which receives effluents from industries located in North Chennai Coastal region. Concentrations of Cd (64.21 microg g(-1)) and Cr (28.51 microg g(-1)) were found to be high in sediment, whereas in green algae concentration of Pb (8.32 microg g(-1)) was higher than water and sediment samples. The relative abundance of these heavy metals in U. lactuca and sediment were found to be in the order Cd>Cr>Pb, whereas in water the ratio was found to be Cr>Pb>Cd. The seasonal variations in Cd and Pb followed a similar pattern in both seaweeds and sediments, but not in water samples. Spearman correlation coefficient study showed no significant correlation in the concentration of metals in U. lactuca, water and sediment samples.

  11. Design of electric-field assisted surface plasmon resonance system for the detection of heavy metal ions in water

    Directory of Open Access Journals (Sweden)

    Htet Htet Kyaw

    2015-10-01

    Full Text Available Surface Plasmon Resonance (SPR sensors are widely used in diverse applications. For detecting heavy metal ions in water, surface functionalization of the metal surface is typically used to adsorb target molecules, where the ionic concentration is detected via a resonance shift (resonance angle, resonance wavelength or intensity. This paper studies the potential of a possible alternative approach that could eliminate the need of using surface functionalization by the application of an external electric field in the flow channel. The exerted electrical force on the ions pushes them against the surface for enhanced adsorption; hence it is referred to as “Electric-Field assisted SPR system”. High system sensitivity is achieved by monitoring the time dynamics of the signal shift. The ion deposition dynamics are discussed using a derived theoretical model based on ion mobility in water. On the application of an appropriate force, the target ions stack onto the sensor surface depending on the ionic concentration of target solution, ion mass, and flow rate. In the experimental part, a broad detection range of target cadmium ions (Cd2+ in water from several parts per million (ppm down to a few parts per billion (ppb can be detected.

  12. Design of electric-field assisted surface plasmon resonance system for the detection of heavy metal ions in water

    Energy Technology Data Exchange (ETDEWEB)

    Kyaw, Htet Htet [Department of Physics, College of Science, Sultan Qaboos University, P. O. Box 36, Al-Khoud 123 (Oman); Boonruang, Sakoolkan, E-mail: sakoolkan.boonruang@nectec.or.th, E-mail: waleed.m@bu.ac.th [Photonics Technology Laboratory, National Electronics and Computer Technology Center (NECTEC), 112 Thailand Science Park, PathumThani 12120 (Thailand); Mohammed, Waleed S., E-mail: sakoolkan.boonruang@nectec.or.th, E-mail: waleed.m@bu.ac.th [Center of Research in Optoelectronics, Communication and Control Systems (BUCROCCS), School of Engineering, Bangkok University, PathumThani 12120 (Thailand); Dutta, Joydeep [Functional Materials Division, School of Information and Communication Technology, KTH Royal Institute of Technology, Isafjordsgatan 22, SE-164 40 Kista, Stockholm (Sweden)

    2015-10-15

    Surface Plasmon Resonance (SPR) sensors are widely used in diverse applications. For detecting heavy metal ions in water, surface functionalization of the metal surface is typically used to adsorb target molecules, where the ionic concentration is detected via a resonance shift (resonance angle, resonance wavelength or intensity). This paper studies the potential of a possible alternative approach that could eliminate the need of using surface functionalization by the application of an external electric field in the flow channel. The exerted electrical force on the ions pushes them against the surface for enhanced adsorption; hence it is referred to as “Electric-Field assisted SPR system”. High system sensitivity is achieved by monitoring the time dynamics of the signal shift. The ion deposition dynamics are discussed using a derived theoretical model based on ion mobility in water. On the application of an appropriate force, the target ions stack onto the sensor surface depending on the ionic concentration of target solution, ion mass, and flow rate. In the experimental part, a broad detection range of target cadmium ions (Cd{sup 2+}) in water from several parts per million (ppm) down to a few parts per billion (ppb) can be detected.

  13. Assessment of Heavy Metals in Water, Sediment, and Fishes of a Large Tropical Hydroelectric Dam in Sarawak, Malaysia

    Directory of Open Access Journals (Sweden)

    Siong Fong Sim

    2016-01-01

    Full Text Available Bakun Hydroelectric Dam in Sarawak is one of the world highest concrete rock filled dams. This paper reports the heavy metals concentrations in water, sediment, and fishes of Bakun Dam. Water and sediment samples were collected from 11 stations and 6 fish species were caught. The samples were digested with open acid digestion and the metals contents were analysed using an atomic absorption spectrophotometer and mercury analyser. The method was validated based on certified reference materials. A higher concentration of Fe and Mn was detected in downstream water with significant longitudinal variation. Cu, Zn, and Hg were present in trace amount. All elements analysed were consistently found in sediment with no risk of contamination. For fish, Hemibagrus planiceps was characterised by higher affinity for Hg accumulation. The concentrations detected in all fish species were within the permissible guideline of 0.5 mg/kg. The health risk assessment suggested that Barbonymus schwanenfeldii, Puntioplites waandersii, Cyclocheilichthys apogon, and Hemibagrus planiceps were characterised by hazard index > 1 implying possible adverse effects. The amount of fish recommended for adults and children was in the range of 500–775 g/week and 33–135 g/week, respectively.

  14. Removing heavy metals in water: the interaction of cactus mucilage and arsenate (As (V)).