Sample records for bruce heavy water
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Parker Snowden
1984-01-01
In the northern part of the USA and in Canada, the caterpillars of Bruce spanworm, Operophtera bruceata (Hulst), attack a variety of hardwood trees, but sugar maple, aspen, and beech are the favored host trees. In areas where these favored host trees are numerous, moderate to severe defoliation will occur. For the past two years, the insect has caused widespread...
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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.
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Bires, Angela Macci; Lawson, Dori; Wasser, Thomas E; Raber-Baer, Donna
2013-12-01
Clinically valid cardiac evaluation via treadmill stress testing requires patients to achieve specific target heart rates and to successfully complete the cardiac examination. A comparison of the standard Bruce protocol and the ramped Bruce protocol was performed using data collected over a 1-y period from a targeted patient population with a body mass index (BMI) equal to or greater than 30 to determine which treadmill protocol provided more successful examination results. The functional capacity, metabolic equivalent units achieved, pressure rate product, and total time on the treadmill as measured for the obese patients were clinically valid and comparable to normal-weight and overweight patients (P < 0.001). Data gathered from each protocol demonstrated that the usage of the ramped Bruce protocol achieved more consistent results in comparison across all BMI groups in achieving 80%-85% of their age-predicted maximum heart rate. This study did not adequately establish that the ramped Bruce protocol was superior to the standard Bruce protocol for the examination of patients with a BMI equal to or greater than 30.
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Drosophila BRUCE inhibits apoptosis through non-lysine ubiquitination of the IAP-antagonist REAPER
Domingues, C; Ryoo, H D
2012-01-01
Active caspases execute apoptosis to eliminate superfluous or harmful cells in animals. In Drosophila, living cells prevent uncontrolled caspase activation through an inhibitor of apoptosis protein (IAP) family member, dIAP1, and apoptosis is preceded by the expression of IAP-antagonists, such as Reaper, Hid and Grim. Strong genetic modifiers of this pathway include another IAP family gene encoding an E2 ubiquitin conjugating enzyme domain, dBruce. Although the genetic effects of dBruce mutants are well documented, molecular targets of its encoded protein have remained elusive. Here, we report that dBruce targets Reaper for ubiquitination through an unconventional mechanism. Specifically, we show that dBruce physically interacts with Reaper, dependent upon Reaper's IAP-binding (IBM) and GH3 motifs. Consistently, Reaper levels were elevated in a dBruce −/− background. Unexpectedly, we found that dBruce also affects the levels of a mutant form of Reaper without any internal lysine residues, which normally serve as conventional ubiquitin acceptor sites. Furthermore, we were able to biochemically detect ubiquitin conjugation on lysine-deficient Reaper proteins, and knockdown of dBruce significantly reduced the extent of this ubiquitination. Our results indicate that dBruce inhibits apoptosis by promoting IAP-antagonist ubiquitination on unconventional acceptor sites. PMID:21886178
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When Ernest Jones First Arrived in Toronto; or, Reappraising the Bruce Letter.
Kuhn, Philip
2018-01-01
In July 1962, Toronto-based surgeon, Herbert Bruce, wrote a private and confidential letter to social worker and historian Cyril Greenland with some memories and impressions of Sigmund Freud's lifelong friend and biographer, Ernest Jones, in Toronto (1908-1913). In the letter, Bruce described Jones as a "sexual pervert." Despite Bruce's condemnation of Jones, historians and biographers have largely ignored his controversial memories of Jones in Toronto. The article traces how scholars have handled the existence of the Bruce letter, and the consequences for how this history has been understood. In the latter half of the article, the author considers how the existence of this letter might offer insights into how the Toronto medical establishment regarded Ernest Jones.
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METHOD OF OPERATING A HEAVY WATER MODERATED REACTOR
Vernon, H.C.
1962-08-14
A method of removing fission products from the heavy water used in a slurry type nuclear reactor is described. According to the process the slurry is steam distilled with carbon tetrachloride so that at least a part of the heavy water and carbon tetrachloride are vaporized; the heavy water and carbon tetrachloride are separated; the carbon tetrachloride is returned to the steam distillation column at different points in the column to aid in depositing the slurry particles at the bottom of the column; and the heavy water portion of the condensate is purified. (AEC)
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HL-10 after first flight with pilot Bruce Peterson
NASA Technical Reports Server (NTRS)
1966-01-01
The HL-10 after its first flight, shown with pilot Bruce Peterson. Although the lifting-body aircraft was predicted to have good flying qualities, this first flight showed major control and stability problems. The cause was airflow separation from the vehicle's fins. Changes to the fins' leading-edge shape fixed the problem. The HL-10 was one of five heavyweight lifting-body designs flown at NASA's Flight Research Center (FRC--later Dryden Flight Research Center), Edwards, California, from July 1966 to November 1975 to study and validate the concept of safely maneuvering and landing a low lift-over-drag vehicle designed for reentry from space. Northrop Corporation built the HL-10 and M2-F2, the first two of the fleet of 'heavy' lifting bodies flown by the NASA Flight Research Center. The contract for construction of the HL-10 and the M2-F2 was $1.8 million. 'HL' stands for horizontal landing, and '10' refers to the tenth design studied by engineers at NASA's Langley Research Center, Hampton, Va. After delivery to NASA in January 1966, the HL-10 made its first flight on Dec. 22, 1966, with research pilot Bruce Peterson in the cockpit. Although an XLR-11 rocket engine was installed in the vehicle, the first 11 drop flights from the B-52 launch aircraft were powerless glide flights to assess handling qualities, stability, and control. In the end, the HL-10 was judged to be the best handling of the three original heavy-weight lifting bodies (M2-F2/F3, HL-10, X-24A). The HL-10 was flown 37 times during the lifting body research program and logged the highest altitude and fastest speed in the Lifting Body program. On Feb. 18, 1970, Air Force test pilot Peter Hoag piloted the HL-10 to Mach 1.86 (1,228 mph). Nine days later, NASA pilot Bill Dana flew the vehicle to 90,030 feet, which became the highest altitude reached in the program. Some new and different lessons were learned through the successful flight testing of the HL-10. These lessons, when combined with
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M2-F2 with test pilot Bruce A. Peterson
1966-09-22
Bruce A. Peterson standing beside the M2-F2 lifting body on Rogers Dry Lake. Peterson became the NASA project pilot for the lifting body program after Milt Thompson retired from flying in late 1966. Peterson had flown the M2-F1, and made the first glide flight of the HL-10 heavy-weight lifting body in December 1966. On May 10, 1967, Peterson made his fourth glide flight in the M2-F2. This was also the M2-F2's 16th glide flight, scheduled to be the last one before the powered flights began. However, as pilot Bruce Peterson neared the lakebed, the M2-F2 suffered a pilot induced oscillation (PIO). The vehicle rolled from side to side in flight as he tried to bring it under control. Peterson recovered, but then observed a rescue helicopter that seemed to pose a collision threat. Distracted, Peterson drifted in a cross-wind to an unmarked area of the lakebed where it was very difficult to judge the height over the lakebed because of a lack of the guidance the markers provided on the lakebed runway. Peterson fired the landing rockets to provide additional lift, but he hit the lakebed before the landing gear was fully down and locked. The M2-F2 rolled over six times, coming to rest upside down. Pulled from the vehicle by Jay King and Joseph Huxman, Peterson was rushed to the base hospital, transferred to March Air Force Base and then the UCLA Hospital. He recovered but lost vision in his right eye due to a staph infection.
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78 FR 68455 - Bruce I. Diamond; Denial of Hearing; Final Debarment Order
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-14
... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2000-N-0110] Bruce I. Diamond; Denial of Hearing; Final Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is denying Dr. Bruce I. Diamond's request...
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``Heavy-water Lattice and Heavy-Quark''
NASA Astrophysics Data System (ADS)
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.
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NASA Astrophysics Data System (ADS)
Tenn, J. S.
2001-12-01
The Astronomical Society of the Pacific (ASP) has presented the Catherine Wolfe Bruce gold medal for lifetime contributions to astronomy most years since 1898. The 94 medalists include most of the scientists whose work has greatly changed astronomy since the late nineteenth century: Huggins, Pickering, Campbell, Hale, Eddington, Russell, Adams, Slipher, Hertzsprung, Hubble, Shapley, Oort, Baade, ... Major exceptions include those who died young, those who worked in teams, and, in the early years, women. Mathematicians appear to have been as likely to be honored as astronomers from the beginning, but the fortunes of physicist nominees have varied. The nomination process is an unusual one, with the directors of six observatories, three in the U.S. and three abroad, asked to nominate up to three candidates each year. For the first six decades the observatories rarely varied, and directors had long tenures. They nominated the same individuals repeatedly. Now both observatories and their directors vary regularly. Much can be learned about the changes in astronomy from the late nineteenth century, when observers worked alone with long refractors and a theorist could spend a lifetime computing the orbit of one comet, to the present, when most papers have multiple authors and a single project may include millions of objects. For example, celestial mechanics was the specialty of many of the early medalists but none since 1966. I have posted photographs, brief biographies, extensive bibliographies, and links to publications by and about all of the medalists, from Simon Newcomb in 1898 to Hans Bethe in 2001, at http://phys-astro.sonoma.edu/BruceMedalists/. I will discuss a bit of the history of the medal and some of the medalists.
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A Drinking Water Sensor for Lead and Other Heavy Metals.
Lin, Wen-Chi; Li, Zhongrui; Burns, Mark A
2017-09-05
Leakage of lead and other heavy metals into drinking water is a significant health risk and one that is not easily detected. We have developed simple sensors containing only platinum electrodes for the detection of heavy metal contamination in drinking water. The two-electrode sensor can identify the existence of a variety of heavy metals in drinking water, and the four-electrode sensor can distinguish lead from other heavy metals in solution. No false-positive response is generated when the sensors are placed in simulated and actual tap water contaminated by heavy metals. Lead detection on the four-electrode sensor is not affected by the presence of common ions in tap water. Experimental results suggest the sensors can be embedded in water service lines for long-time use until lead or other heavy metals are detected. With its low cost (∼$0.10/sensor) and the possibility of long-term operation, the sensors are ideal for heavy metal detection of drinking water.
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Geoscientific Characterization of the Bruce Site, Tiverton, Ontario
NASA Astrophysics Data System (ADS)
Raven, K.; Jackson, R.; Avis, J.; Clark, I.; Jensen, M.
2009-05-01
Ontario Power Generation is proposing a Deep Geologic Repository (DGR) for the long-term management of its Low and Intermediate Level Radioactive Waste (L&ILW) within a Paleozoic-age sedimentary sequence beneath the Bruce site near Tiverton, Ontario, Canada. The concept envisions that the DGR would be excavated at a depth of approximately 680 m within the Ordovician Cobourg Formation, a massive, dense, low- permeability, argillaceous limestone. Characterization of the Bruce site for waste disposal is being conducted in accordance with a four year multi-phase Geoscientific Site Characterization Plan (GSCP). The GSCP, initially developed in 2006 and later revised in 2008 to account for acquired site knowledge based on successful completion of Phase I investigations, describes the tools and methods selected for geological, hydrogeological and geomechanical site characterization. The GSCP was developed, in part, on an assessment of geoscience data needs and collection methods, review of the results of detailed geoscientific studies completed in the same bedrock formations found off the Bruce site, and recent international experience in geoscientific characterization of similar sedimentary rocks for long-term radioactive waste management purposes. Field and laboratory work related to Phase 1 and Phase 2A are nearing completion and have focused on the drilling, testing and monitoring of four continuously cored vertical boreholes through Devonian, Silurian, Ordovician and Cambrian bedrock to depths of about 860 mBGS. Work in 2009 will focus on drilling and testing of inclined boreholes to assess presence of vertical structure. The available geological, hydrogeological and hydrogeochemical data indicate the presence of remarkably uniform and predictable geology, physical hydrogeologic and geochemical properties over well separation distances exceeding 1 km. The current data set including 2-D seismic reflection surveys, field and lab hydraulic testing, lab petrophysical and
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Evaluation of pheromone-baited traps for winter moth and Bruce spanworm (Lepidoptera: Geometridae).
Elkinton, Joseph S; Lance, David; Boettner, George; Khrimian, Ashot; Leva, Natalie
2011-04-01
We tested different pheromone-baited traps for surveying winter moth, Operophtera brumata (L.) (Lepidoptera: Geometridae), populations in eastern North America. We compared male catch at Pherocon 1C sticky traps with various large capacity traps and showed that Universal Moth traps with white bottoms caught more winter moths than any other trap type. We ran the experiment on Cape Cod, MA, where we caught only winter moth, and in western Massachusetts, where we caught only Bruce spanworm, Operophtera bruceata (Hulst) (Lepidoptera: Geometridae), a congener of winter moth native to North America that uses the same pheromone compound [(Z,Z,Z)-1,3,6,9-nonadecatetraene] and is difficult to distinguish from adult male winter moths. With Bruce spanworm, the Pherocon 1C sticky traps caught by far the most moths. We tested an isomer of the pheromone [(E,Z,Z)-1,3,6,9-nonadecatetraene] that previous work had suggested would inhibit captures of Bruce spanworm but not winter moths. We found that the different doses and placements of the isomer suppressed captures of both species to a similar degree. We are thus doubtful that we can use the isomer to trap winter moths without also catching Bruce spanworm. Pheromone-baited survey traps will catch both species.
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Extension of the TRANSURANUS burnup model to heavy water reactor conditions
NASA Astrophysics Data System (ADS)
Lassmann, K.; Walker, C. T.; van de Laar, J.
1998-06-01
The extension of the light water reactor burnup equations of the TRANSURANUS code to heavy water reactor conditions is described. Existing models for the fission of 235U and the buildup of plutonium in a heavy water reactor are evaluated. In order to overcome the limitations of the frequently used RADAR model at high burnup, a new model is presented. After verification against data for the radial distributions of Xe, Cs, Nd and Pu from electron probe microanalysis, the model is used to analyse the formation of the high burnup structure in a heavy water reactor. The new model allows the analysis of light water reactor fuel rod designs at high burnup in the OECD Halden Heavy Water Reactor.
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Magnetic process for removing heavy metals from water employing magnetites
Prenger, F. Coyne; Hill, Dallas D.; Padilla, Dennis D.; Wingo, Robert M.; Worl, Laura A.; Johnson, Michael D.
2003-07-22
A process for removing heavy metals from water is provided. The process includes the steps of introducing magnetite to a quantity of water containing heavy metal. The magnetite is mixed with the water such that at least a portion of, and preferably the majority of, the heavy metal in the water is bound to the magnetite. Once this occurs the magnetite and absorbed metal is removed from the water by application of a magnetic field. In most applications the process is achieved by flowing the water through a solid magnetized matrix, such as steel wool, such that the magnetite magnetically binds to the solid matrix. The magnetized matrix preferably has remnant magnetism, but may also be subject to an externally applied magnetic field. Once the magnetite and associated heavy metal is bound to the matrix, it can be removed and disposed of, such as by reverse water or air and water flow through the matrix. The magnetite may be formed in-situ by the addition of the necessary quantities of Fe(II) and Fe(III) ions, or pre-formed magnetite may be added, or a combination of seed and in-situ formation may be used. The invention also relates to an apparatus for performing the removal of heavy metals from water using the process outlined above.
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Magnetic process for removing heavy metals from water employing magnetites
Prenger, F. Coyne; Hill, Dallas D.
2006-12-26
A process for removing heavy metals from water is provided. The process includes the steps of introducing magnetite to a quantity of water containing heavy metal. The magnetite is mixed with the water such that at least a portion of, and preferably the majority of, the heavy metal in the water is bound to the magnetite. Once this occurs the magnetite and absorbed metal is removed from the water by application of a magnetic field. In most applications the process is achieved by flowing the water through a solid magnetized matrix, such as steel wool, such that the magnetite magnetically binds to the solid matrix. The magnetized matrix preferably has remnant magnetism, but may also be subject to an externally applied magnetic field. Once the magnetite and associated heavy metal is bound to the matrix, it can be removed and disposed of, such as by reverse water or air and water flow through the matrix. The magnetite may be formed in-situ by the addition of the necessary quantities of Fe(II) and Fe(III) ions, or pre-formed magnetite may be added, or a combination of seed and in-situ formation may be used. The invention also relates to an apparatus for performing the removal of heavy metals from water using the process outlined above.
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Komai, Tomoyuki; Grave, Sammy De; Saito, Tomomi
2016-05-17
Two new species of the deep-water spongicolid genus Spongiocaris Bruce & Baba, 1973, are described and illustrated from two localities in the Indo-West Pacific. Spongiocaris panglao n. sp. is described on the basis of material from the Bohol Sea, the Philippines, at depths of 220-731 m. Spongiocaris tuerkayi n. sp. is described on the basis of material from Atlantis Bank in the southwestern Indian Ocean at depths of 743-1053 m. Among eight known congeners, both new species appear close to S. semiteres Bruce & Baba, 1973, differing in the rostral length and armature, shape of the carapace, telsonal armature, development of the grooming apparatus of the first pereopod and shape of the third pereopod chela. An identification key to the species currently assigned to Spongiocaris is presented.
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Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.
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.
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Simulation - McCandless, Bruce (Syncom IV)
1985-04-15
S85-30800 (14 April 1985) --- Astronaut Bruce McCandless II tests one of the possible methods of attempting to activate a switch on the Syncom-IV (LEASAT) satellite released April 13 into space from the Space Shuttle Discovery. The communications spacecraft failed to behave properly upon release and NASA officials and satellite experts are considering possible means of repair. McCandless was using a full scale mockup of the satellite in the Johnson Space Center's (JSC) mockup and integration laboratory.
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An interview with Bruce A. Bolt
Spall, H.
1987-01-01
Professor Bruce Bolt was educated in Australia and first came to the United States in 1960 on a Fulbright Fellowship to the Lamont Geological Observatory of Columbia University. In 1963 he was appointed Director of the Seismographic Stations at the University of California at Berkeley. In June 1988, he steps down as Director but his association will continue as Professor of Seismology. Henry Spall interviewed him again 10 years after a 977 interview published in the Earthquake Information Bulletin.
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Astronaut Bruce McCandless tests astronaut maneuvering unit
1973-08-16
S72-30704 (1972) --- Astronaut Bruce McCandless II, backup pilot for Skylab 2, tests the balance and control of an astronaut maneuvering unit (AMU) test model at Martin Marietta Corporation's Denver division. The jet-powered backpack can fly for 30 minutes and can be worn over normal clothing or spacesuit. Photo credit: NASA
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Heavy metals analysis and quality assessment in drinking water - Khorramabad city, Iran.
Ghaderpoori, Mansour; Kamarehie, Bahram; Jafari, Ali; Ghaderpoury, Afshin; Karami, Mohammadamin
2018-02-01
Continuous monitoring of drinking water quality is essential in terms of heavy metals and toxic substances. The general objective of this study were to determine the concentration of heavy metals in drinking water of Khorramabad city and to determine the water quality indices (The heavy metal pollution index and heavy metal evaluation index). According to the city map, 45 points were selected for drinking water sampling through the city distribution system. The results of this study showed that the average concentration of heavy metals such as Zn, Pb, Cd, Cr, and Cu were 47.01 μg/l, 3.2 μg/l, 0.42 μg/l, 5.08 μg/l, and 6.79 μg/l, respectively. The HPI and HEI (water quality indices) for Zn, Pb, Cd, Cr, and Cu were 46.58, 46.58, respectively. According to the indices, the city drinking water quality is good in terms of heavy metals.
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Bruce Wiegman with a tether for the Electostatic Propulsion System.
2015-09-30
BRUCE WIEGMANN, AN ENGINEER AT NASA'S MARSHALL SPACE FLIGHT CENTER IN HUNTSVILLE, ALABAMA, EXAMINES A HAIR-THIN TETHER THAT WILL BE PART OF AN ELECTROSTATIC PROPULSION SYSTEM THAT COULD SEND SPACECRAFT ON INTERSTELLAR MISSIONS.
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Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ...
Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ANGELES CITY HALL SIXTH FLOOR NORTH OFFICE AREA, FACING NORTH - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA
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Bruce D. Judd, FAIA, Photographer August 1997. DETAIL OF LOS ...
Bruce D. Judd, FAIA, Photographer August 1997. DETAIL OF LOS ANGELES CITY HALL SIXTH FLOOR NORTH OFFICE AREA WINDOW, FACING NORTHWEST - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA
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Black water sludge reuse in agriculture: are heavy metals a problem?
Tervahauta, Taina; Rani, Sonia; Hernández Leal, Lucía; Buisman, Cees J N; Zeeman, Grietje
2014-06-15
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 soil. Source-separation of black water (toilet water) excludes external heavy metal inputs, such as industrial effluents and surface run-offs, producing sludge with reduced heavy metal content that is a more favorable source for resource recovery. The results presented in this paper show that feces is the main contributor to the heavy metal loading of vacuum collected black water (52-84%), while in sewage the contribution of feces is less than 10%. To distinguish black water from sewage in the sludge reuse regulation, a control parameter should be implemented, such as the Hg and Pb content that is significantly higher in sewage sludge compared to black water sludge (from 50- to 200-fold). The heavy metals in feces and urine are primarily from dietary sources, and promotion of the soil application of black water sludge over livestock manure and artificial fertilizers could further reduce the heavy metal content in the soil/food cycle. Copyright © 2014 Elsevier B.V. All rights reserved.
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76 FR 52994 - Application for a License To Export Heavy Water
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-24
... NUCLEAR REGULATORY COMMISSION Application for a License To Export Heavy Water Pursuant to 10 CFR... (liters). producing an active water). pharmaceutical ingredient known as CTP-499, which incorporates heavy water as the source of deuterium to achieve the hydrogen-deuterium exchange. November 30, 2010 December...
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Heavy metal displacement in salt-water-irrigated soil during phytoremediation.
Wahla, Intkhab Hazoor; Kirkham, M B
2008-09-01
In regions where phytoremediation is carried out, brackish water must often be used. However, no information exists concerning the consequences of saline-water irrigation on the mobility of heavy metals in sludge applied to soil during phytoremediation. The purpose of this experiment was to determine the effect of NaCl irrigation on displacement of seven heavy metals in sludge (Cd, Cu, Fe, Mn, Ni, Pb, Zn) applied to the surface of soil columns containing barley plants. Half the columns received NaCl irrigation (10,000 mg L(-1)) and half the columns received tap-water irrigation. Half the columns were treated with the chelating agent EDTA. With no EDTA, irrigation with the NaCl solution increased the concentrations of Cd, Fe, Mn, and Pb in the drainage water above drinking-water standards. Irrigation of sludge farms with brackish water is not recommended, because saline water increased the mobility of the heavy metals and they polluted the drainage water.
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Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ...
Bruce D. Judd, FAIA, Photographer August 1997. VIEW OF LOS ANGELES CITY HALL ELEVENTH FLOOR KITCHEN OF EXECUTIVE DINING AREA SHOWING ARCHED STRUCTURE, FACING NORTHWEST - Los Angeles City Hall, 200 North Spring Street, Los Angeles, Los Angeles County, CA
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Skull Size and Intelligence, and King Robert Bruce's IQ
ERIC Educational Resources Information Center
Deary, Ian J.; Ferguson, Karen J.; Bastin, Mark E.; Barrow, Geoffrey W. S.; Reid, Louise M.; Seckl, Jonathan R.; Wardlaw, Joanna M.; MacLullich, Alasdair M. J.
2007-01-01
An estimate of someone's IQ is a potentially informative personal datum. This study examines the association between external skull measurements and IQ scores, and uses the resulting regression equation to provide an estimate of the IQ of King Robert I of Scotland (Robert Bruce, 1274-1329). Participants were 48 relatively healthy Caucasian men…
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"Periodic-table-style" paper device for monitoring heavy metals in water.
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.
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Influence of Heavy Metal Stress On Water Regime of A Model Forest Ecosystem
NASA Astrophysics Data System (ADS)
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
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Feng, Chenghong; Guo, Xiaoyu; Yin, Su; Tian, Chenhao; Li, Yangyang; Shen, Zhenyao
2017-10-01
The partitioning of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) between the water, suspended particulate matter (SPM), and sediments in seven channel sections during three hydrologic seasons in the Yangtze Estuary was comprehensively investigated. Special attention was paid to the role of tides, influential factors (concentrations of SPM and dissolved organic carbon, and particle size), and heavy metal speciation. The SPM-water and sediment-water partition coefficients (K p ) of the heavy metals exhibited similar changes along the channel sections, though the former were larger throughout the estuary. Because of the higher salinity, the K p values of most of the metals were higher in the north branch than in the south branch. The K p values of Cd, Co, and As generally decreased from the wet season to the dry season. Both the diagonal line method and paired samples t-test showed that no specific phase transfer of heavy metals existed during the flood and ebb tides, but the sediment-water K p was more concentrated for the diagonal line method, owing to the relatively smaller tidal influences on the sediment. The partition coefficients (especially the K p for SPM-water) had negative correlations with the dissolved organic carbon (DOC) but positive correlations were noted with the particle size for most of the heavy metals in sediment. Two types of significant correlations were observed between K p and metal speciation (i.e., exchangeable, carbonate, reducible, organic, and residual fractions), which can be used to identify the dominant phase-partition mechanisms (e.g., adsorption or desorption) of heavy metals. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Removal of gadolinium nitrate from heavy water
DOE Office of Scientific and Technical Information (OSTI.GOV)
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 andmore » a reduction in the quantity of secondary waste materials produced by the current baseline process (ion exchange).« less
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NASA Astrophysics Data System (ADS)
Li, Fabing; Li, Zhanlong; Li, Shuo; Fang, Wenhui; Sun, Chenglin; Men, Zhiwei
2018-06-01
Stimulated Raman scattering (SRS) of liquid water and heavy water have been investigated using Nd:YAG laser. The SRS spectra of liquid heavy water indicate that ice-VII and ice-VIII structures are formed by shock-induced compression (SIC) in forward and backward directions, respectively. Simultaneously, the SRS spectra reveal of liquid water that only ice-VII structure is formed in the backward direction. The difference in ice structures formed by SIC in liquid water and heavy water could be attributed to the effect of the hydrogen bond quantum nature with H+. SRS spectra of 2 M NaOH water solution with ice-VII and ice-VIII structures have been successfully obtained in forward and backward, respectively, as OH- greatly reduce the quantum nature of hydrogen bonds by neutralizing H+ in water. The hydrogen bond quantum nature is important for understanding isotope calibration test structure and isotopic effect.
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PRODUCTION OF HEAVY WATER SAVANNAH RIVER AND DANA PLANTS. Technical Manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bebbington, W.P.; Thayer, V.R. eds.; Proctor, J.F. comp.
1959-07-01
A summary is presented of the basic technical iniormation that pertains to processes that are used at the Dana and Savannah River Plants for the production of heavy water. The manual is intended primarily for plant operating and technical personnel and was prepared to supplement and provide technical support for detailed operating procedures. Introductory sections contain some background information on the history, uses, available processes, and analytical procedures for heavy water. They also include a general comparison of the design and laserformance of the two plants and an analysis of their differences. The technology of the heavy water separation processesmore » used, namely hydrogen sulfide exchange, distillation of water, and electrolysis is discussed in detail. The manufacture and storage of hydrogen sulfide gas and the process water treatment facilities are also discussed. (auth)« less
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[Effect of Recycled Water Irrieation on Heavy Metal Pollution in Irrigation Soil].
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.
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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.
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Experimental Study on Behavior of Bow-tie Tree Generation by Using Heavy Water
NASA Astrophysics Data System (ADS)
Kumazawa, Takao; Nakagawa, Wataru; Tsurumaru, Hidekazu
Bow-tie tree (BTT) generated from contaminant, e.g., metal, carbon, amber(over cured resin) or void in insulator is a significant deterioration factor of XLPE power cable. However, essential role of water in generation and progress of BTT is not yet sufficiently cleared. In order to investigate the role of water we paid attention to difference in chemical properties of light water (H2O) and heavy water (D2O), moreover we evaluated influence of isotopic effect due to hydrogen and deuterium on behavior of BTT generation. In accelerated aging test the number of BTT in XLPE sample, in which copper powder of 500ppm was contaminated as BTT cores, dipped in heavy water (D2O:100wt%) decreased to one third compared with light water(D2O:0wt%). Furthermore, the maximum length of BTT decreased with increase in concentration of heavy water. The experimental results show that heavy water exerted a depression effect on generation and progress of BTT. We considered that the depression effect due to hydrogen isotope appeared by inhibiting ionization and elution of BTT cores, because salt-solubility and ionic mobility of heavy water are about 15 to 20% smaller than those of light water. Therefore, the essential role of water seemed to be production and transport of ions in XLPE.
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NASA Astrophysics Data System (ADS)
Kurudirek, Murat
2015-09-01
Some gel dosimeters, water, human tissues and water phantoms were investigated with respect to their radiological properties in the energy region 10 keV-10 MeV. The effective atomic numbers (Zeff) and electron densities (Ne) for some heavy charged particles such as protons, He ions, B ions and C ions have been calculated for the first time for Fricke, MAGIC, MAGAT, PAGAT, PRESAGE, water, adipose tissue, muscle skeletal (ICRP), muscle striated (ICRU), plastic water, WT1 and RW3 using mass stopping powers from SRIM Monte Carlo software. The ranges and straggling were also calculated for the given materials. Two different set of mass stopping powers were used to calculate Zeff for comparison. The water equivalence of the given materials was also determined based on the results obtained. The Monte Carlo simulation of the charged particle transport was also done using SRIM code. The heavy ion distribution along with its parameters were shown for the given materials for different heavy ions. Also the energy loss and damage events in water when irradiated with 100 keV heavy ions were studied in detail.
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Hang, Xiao-Shuai; Wang, Huo-Yan; Zhou, Jian-Min
2008-10-01
Surface water and shallow groundwater within the flow of an electroplating factory was analyzed in order to study the resulting impact. The analysis method of ICP-AES was used to analyze content of zinc, manganese, chromium, copper and nickel in surface water and groundwater samples. The results indicate acidic pollutants of zinc, manganese, chromium, copper and nickel were discharged from the factory with concentrations of 1.34, 3.77, 28.1, 6.40 and 9.37 mg x L(-1), respectively; and pH was 2.32. They all exceeded permissible levels according to Integrated Wastewater Discharge Standard except zinc. Factory discharge is responsible for the longitudinal distribution characteristics of heavy metals in the stream water downstream from the factory. Heavy metals variations in the well water do not suggest they were affected by heavy metals in the stream, indicating that the migration rates of heavy metals in soils were relatively low. Risk assessment shows surface water quality significantly deteriorated. Nickel and manganese in the stream water exceeded the standard levels seriously, and chromium and copper in some samples were also above Grade III standard levels according to Environmental Quality Standard for Surface Water. Moreover, all studied heavy metals in 14 groundwater samples measured within drinking water standard, except manganese in 4 groundwater samples, which were Grade IV according to Quality Standard for Ground water.
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Assessment of heavy metals in loose deposits in drinking water distribution system.
Liu, Quanli; Han, Weiqiang; Han, Bingjun; Shu, Min; Shi, Baoyou
2018-06-09
Heavy metal accumulation and potential releases from loose deposits in drinking water distribution system (DWDS) can have critical impacts on drinking water safety, but the associated risks have not been sufficiently evaluated. In this work, the potential biological toxicity of heavy metals in loose deposits was calculated based on consensus-based sediment quality guidelines, and the effects of some of the main water quality parameters, such as the pH and bicarbonate and phosphate content, on the release behaviors of pre-accumulated heavy metals were investigated. The results showed that heavy metals (Cu, As, Cr, Pb, and Cd) significantly accumulated in all the samples, but the contents of the heavy metals were multiple magnitudes lower than the Fe and Mn contents. The potential biotoxicity of As and Cu was relatively high, but the biotoxicity of Cd was negligible. The water quality can significantly influence the release of heavy metals from loose deposits. As the pH increased from 7.0 to 9.0, the release of As and Cr obviously increased. The release of As, Cu, Pb, and Cr also accelerated with the addition of phosphate (from 1 to 5 mg/L). In contrast to the trends for the pH and phosphate, variations in the bicarbonate content did not have a significant influence on the release of As and Cr. The release ratios of heavy metals in the samples were very low, and there was not a correlation between the release rate of the heavy metals in the loose deposits and their potential biotoxicity.
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43. Historic photo of Bruce Lundin posing in front of ...
43. Historic photo of Bruce Lundin posing in front of observation window in exhaust cone at base of test stand A in Building 202, September 1960. On file at NASA Plumbrook Research Center, Sandusky, Ohio. NASA photo number C-53170. - Rocket Engine Testing Facility, GRC Building No. 202, NASA Glenn Research Center, Cleveland, Cuyahoga County, OH
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Water hyacinth as indicator of heavy metal pollution the tropics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonzalez, H.; Otero, M.; Lodenius, M.
1989-12-01
The water hyacinth (Eichhornia crassipes) is a common aquatic plant in many tropical countries. Its ability absorb nutrients and other elements from the water has made it possible to use it for water purification purposes. Eichhornia, especially stems and leaves, have been successfully used as indicators of heavy metal pollution in tropical countries. The uptake of heavy metals in this plant is stronger in the roots than in the floating shoots. Metallothionein-like compounds have been found from roots of this species after cadmium exposure. The purpose of this investigation was to study the possibilities of using roots of water hyacinthmore » as a biological indicator of metal pollution in tropical aquatic ecosystems.« less
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A Journey toward Excellence: An Interview with Bruce M. Shore
ERIC Educational Resources Information Center
Henshon, Suzanna E.
2010-01-01
Bruce M. Shore is in his 39th year as a Professor of Educational Psychology in the Department of Educational and Counseling Psychology at McGill University in Montreal, Quebec, Canada, and Associate Director (McGill) of the multi-campus Centre for the Study of Learning and Performance. For 21 years he was jointly appointed as a member of the…
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Thomas Bruce Ferguson, MD, May 6, 1923-May 26, 2013.
Patterson, G Alexander
2014-04-01
Thomas Bruce Ferguson, the 12th president of The Society of Thoracic Surgeons, died surrounded by his family on May 26, 2013. He was a legendary figure in the world of cardiothoracic surgery. His visionary leadership was an inspiration to generations of cardiothoracic surgeons around the world. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
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"He's Supportive, Period": A Tribute to Bertram (Chip) Bruce
ERIC Educational Resources Information Center
Hogan, Maureen
2014-01-01
In this personal and revealing essay, the author traces her relationship with Chip Bruce, from its beginnings, when he served on her dissertation committee, to the present, when she realizes that she is paying forward to her own graduate students the fruits of community inquiry and supportive teaching and learning.
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Nezis, Ioannis P; Shravage, Bhupendra V; Sagona, Antonia P; Lamark, Trond; Bjørkøy, Geir; Johansen, Terje; Rusten, Tor Erik; Brech, Andreas; Baehrecke, Eric H; Stenmark, Harald
2010-08-23
Autophagy is an evolutionarily conserved pathway responsible for degradation of cytoplasmic material via the lysosome. Although autophagy has been reported to contribute to cell death, the underlying mechanisms remain largely unknown. In this study, we show that autophagy controls DNA fragmentation during late oogenesis in Drosophila melanogaster. Inhibition of autophagy by genetically removing the function of the autophagy genes atg1, atg13, and vps34 resulted in late stage egg chambers that contained persisting nurse cell nuclei without fragmented DNA and attenuation of caspase-3 cleavage. The Drosophila inhibitor of apoptosis (IAP) dBruce was found to colocalize with the autophagic marker GFP-Atg8a and accumulated in autophagy mutants. Nurse cells lacking Atg1 or Vps34 in addition to dBruce contained persisting nurse cell nuclei with fragmented DNA. This indicates that autophagic degradation of dBruce controls DNA fragmentation in nurse cells. Our results reveal autophagic degradation of an IAP as a novel mechanism of triggering cell death and thereby provide a mechanistic link between autophagy and cell death.
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An appreciation of Bruce and Young's (1986) serial stage model of face naming after 25 years.
Hanley, J Richard
2011-11-01
The current status of Bruce and Young's (1986) serial model of face naming is discussed 25 years after its original publication. In the first part of the paper, evidence for and against the serial model is reviewed. It is argued that there is no compelling reason why we should abandon Bruce and Young's claim that recall of a name is contingent upon prior retrieval of semantic information about the person. The current status of the claim that people's names are more difficult to recall than the names of objects is then evaluated. Finally, an account of the anatomical location in the brain of Bruce and Young's three processing stages (face familiarity, retrieval of semantic information, retrieval of names) is suggested. In particular, there is evidence that biographical knowledge about familiar people is stored in the right anterior temporal lobes (ATL) and that the left temporal pole (TP) is heavily involved in retrieval of the names of familiar people. The issue of whether these brain areas play a similar role in object processing is also discussed. ©2011 The British Psychological Society.
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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.
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Arshad, Jahanzaib; Iqbal, Farhat; Sajjad, Ashif; Mehmood, Zahid
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. PMID:25276818
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Nuclear fusion at heavy water clusters collision with deuterized targets
NASA Astrophysics Data System (ADS)
Bolotin, Yu. L.; Inopin, E. V.; Lyashko, Yu. V.; Slabospitskij, R. P.
A review of research developed in different laboratories on animal heavy particle yield in D-D fusion reactions induced by heavy water cluster collisions with deuterized targets is presented. Analysis of data shows, on one hand, nontriviality of experimental results and inadequacy of their interpretation and, on the other hand, the multipromising prospects of such a research.
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HEAVY WATER MODERATED NEUTRONIC REACTOR
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.
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Analysis of heavy metal sources in storm water from urban areas
NASA Astrophysics Data System (ADS)
Scherer, U.; Fuchs, S.
2009-04-01
The input of heavy metals into surface waters is a serious impairment of the aquatic environment. The emissions of heavy metals via point and diffuse pathways into the German river basins were thus quantified for the period of 1985 through 2005. The total emission into the German river systems decreased for each metal during the observed period. This reduction is mainly caused by the decline of emissions via point sources. The measures taken by industry and implemented within the scope of a stringently water legislation have decisively contributed to an improvement of environmental conditions. Today's emissions of heavy metals into river basins of Germany are dominated by the input via diffuse pathways. One of the most important diffuse input is the storm water discharged from paved urban areas into the surface waters via storm sewers and combined sewer overflows especially for the metals copper, zinc and lead. The objective of this project was to identify the sources of these three heavy metals washed of from paved urban areas. The use of copper, zinc and lead on the outsides of buildings results in emissions to water and soil via rainwater due to weathering and runoff of soluble and insoluble metallic compounds. Copper and zinc are traditionally used materials in the building sector especially for roofs, gutters and facades. Lead, in contrast, plays only a subordinate role due to its more limited outdoor use. The corrosion rates vary widely. Climatic factors (temperature, humidity etc.), above all the presence of corrosive gases (sulphur dioxide, nitrogen oxide, ozone etc.) influence the corrosion processes. Estimates of industrial associations were referred to in order to determine the corrosion relevant metal surfaces. Heavy metal emissions caused by traffic are complex and depend on many parameters which vary by locality, time and substance. In principle, substances can be emitted by vehicles, the road surface and by maintenance. Emissions of copper, lead and
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Leaching of Heavy Metals from Water Bottle Components into the Drinking Water of Rodents
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
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Leaching of heavy metals from water bottle components into the drinking water of rodents.
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.
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Significant Features of Warm Season Water Vapor Flux Related to Heavy Rainfall and Draught in Japan
NASA Astrophysics Data System (ADS)
Nishiyama, Koji; Iseri, Yoshihiko; Jinno, Kenji
2009-11-01
In this study, our objective is to reveal complicated relationships between spatial water vapor inflow patterns and heavy rainfall activities in Kyushu located in the western part of Japan, using the outcomes of pattern recognition of water vapor inflow, based on the Self-Organizing Map. Consequently, it could be confirmed that water vapor inflow patterns control the distribution and the frequency of heavy rainfall depending on the direction of their fluxes and the intensity of Precipitable water. Historically serious flood disasters in South Kyushu in 1993 were characterized by high frequency of the water vapor inflow patterns linking to heavy rainfall. On the other hand, severe draught in 1994 was characterized by inactive frontal activity that do not related to heavy rainfall.
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Ismail, Amir; Riaz, Muhammad; Akhtar, Saeed; Ismail, Tariq; Amir, Mamoona; Zafar-ul-Hye, Muhammad
2014-01-01
Heavy metal contamination in the food chain is of serious concern due to the potential risks involved. The results of this study revealed the presence of maximum concentration of heavy metals in the canal followed by sewerage and tube well water. Similarly, the vegetables and respective soils irrigated with canal water were found to have higher heavy metal contamination followed by sewerage- and tube-well-watered samples. However, the heavy metal content of vegetables under study was below the limits as set by FAO/WHO, except for lead in canal-water-irrigated spinach (0.59 mg kg(-1)), radish pods (0.44 mg kg(-1)) and bitter gourd (0.33 mg kg(-1)). Estimated daily intakes of heavy metals by the consumption of selected vegetables were found to be well below the maximum limits. However, a complete estimation of daily intake requires the inclusion of other dietary and non-dietary exposure sources of heavy metals.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kay, S.H.; Haller, W.T.
1986-08-01
Both aquatic and terrestrial habitats frequently are subject to contamination by toxic heavy metals, yet very little is known about the influence of heavy metals absorbed by plant tissues upon the phytophagous insect fauna feeding upon these plants. The objectives of this study were to determine the influence of plant-absorbed metals upon the feeding, mortality, and body burdens of lead, cadmium, and copper in the water hyacinth weevil, Neochetina eichhorniae, imported for the biological control of water hyacinths (Eichhornia crassipes).
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NASA Astrophysics Data System (ADS)
Tenn, Joseph S.
2007-12-01
In 2007 the Astronomical Society of the Pacific awarded the 100th Catherine Wolfe Bruce gold medal for lifetime contributions to astronomy. The first medalist, Simon Newcomb in 1898, was a celestial mechanician who supervised the computations of orbits and compilation of almanacs, while the second, Arthur Auwers in 1899, observed visually and compiled catalogs of stellar positions and motions. In contrast the last two medalists, Martin Harwit in 2007 and Frank Low in 2006, are pioneers of infrared astronomy from airplanes and satellites. In between have come theoretical and experimental physicists, mathematicians, and radio astronomers, but the majority of medalists have been optical observers, celestial mechanicians (in the early years) and theoretical astrophysicists. Although astronomers are usually honored with the medal twenty to sixty years after their best work is done, we are starting to see more practitioners of the new astronomies, but to date there have been few representatives of the large teams that now dominate astronomical research. I will present an overview of the medalists and how their fields, styles and demographic characteristics have changed.
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Health risks associated with heavy metals in the drinking water of Swat, northern Pakistan.
Lu, Yonglong; Khan, Hizbullah; Zakir, Shahida; Ihsanullah; Khan, Sardar; Khan, Akbar Ali; Wei, Luo; Wang, Tieyu
2013-10-01
The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources (surface and groundwater) collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake (CDI) and health risk index (HRI) were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr > Mn > Ni > Zn > Cd > Cu > Pb and Cd > Ni > Mn > Cr > Cu > Pb > Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.
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[Heavy metals in environmental media around drinking water conservation area of Shanghai].
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.
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Our GSLIS Colleague, Chip Bruce: An Appreciation. A Deweyan Pragmatist in the Internet Age
ERIC Educational Resources Information Center
Schiller, Dan
2014-01-01
The reconstructive project needed to enable information for democracy, to which Chip Bruce has contributed much, is of long standing. Using a few wide brush strokes, in this article some of the most vital historical contexts for situating this project are supplied.
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NASA Remembers Astronaut Bruce McCandless II
2017-12-22
Former NASA Astronaut Bruce McCandless II, best known for his iconic free-floating spacewalk on a 1984 shuttle flight, died on Dec. 21 at the age of 80. A native of Boston, McCandless II attended the U.S. Naval Academy and served as a naval aviator before joining NASA in 1966. He served in support or backup roles during the Apollo and Skylab programs, including serving as the communicator from mission control to the Apollo 11 crew during their historic 1969 moonwalk. On Feb. 7, 1984, during the Space Shuttle Challenger’s STS-41B mission, he made the first, untethered, free flight spacewalk in the Manned Maneuvering Unit. In 1990, McCandless II was part of the crew on Space Shuttle Discovery’s STS-31 mission, which deployed the Hubble Space Telescope.
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Bruce Thompson: Adventures and advances in ultrasonic backscatter
NASA Astrophysics Data System (ADS)
Margetan, Frank J.
2012-05-01
Over the course of his professional career Dr. R. Bruce Thompson published several hundred articles on non-destructive evaluation, the majority dealing with topics in ultrasonics. One longtime research interest of Dr. Thompson, with applications both to microstructure characterization and defect detection, was backscattered grain noise in metals. Over a 20 year period he led a revolving team of staff members and graduate students investigating various aspects of ultrasonic backscatter. As a member of that team I had the privilege of working along side Dr. Thompson for many years, serving as a sort of Dr. Watson to Bruce's Sherlock Holmes. This article discusses Dr. Thompson's general approaches to modeling backscatter, the research topics he chose to explore to systematically elucidate a better understanding of the phenomena, and the many contributions to the field achieved under his leadership. The backscatter work began in earnest around 1990, motivated by a need to improve inspections of aircraft engine components. At that time Dr. Thompson launched two research efforts. The first led to the heuristic Independent Scatterer Model which could be used to estimate the average grain noise level that would be seen in any given ultrasonic inspection. There the contribution from the microstructure was contained in a measureable parameter known as the Figure-of-Merit or FOM. The second research effort, spearheaded by Dr. Jim Rose, led to a formal relationship between FOM and details of the metal microstructure. The combination of the Independent Scattering Model and Rose's formalism provided a powerful tool for investigating backscatter in metals. In this article model developments are briefly reviewed and several illustrative applications are discussed. These include: the determination of grain size and shape from ultrasonic backscatter; grain noise variability in engine-titanium billets and forgings; and the design of ultrasonic inspection systems to improve defect
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Lu, Shibao; Wang, Jianhua; Pei, Liang
2016-01-01
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. PMID:27005639
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Lu, Shibao; Wang, Jianhua; Pei, Liang
2016-03-08
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.
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Astronaut Bruce McCandless during an underwater test MMU/FSS in bldg 29 WETF
1981-08-04
Astronaut Bruce McCandless during an underwater test of the Manned Maneuvering Unit (MMU) Flight Support Station (FSS) donning and doffing in the Bldg 29 Weightless Environment Training Facility (WETF). View is of McCandless wearing the extravehicular mobility unit (EMU), stepping into the MMU.
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Concentration of heavy metals in drinking water of different localities in district east Karachi.
Jaleel, M A; Noreen, R; Baseer, A
2001-01-01
Several heavy metals are present in drinking water that play important roles in the body provided their level remains within the specified range recommended by WHO. But now due to the industrialization and rapid urbanization, the problems of pollution have surfaced. This study was designed to ascertain the contents of some heavy metals and then their variations if any in drinking water in different localities of district East of Karachi, Pakistan. Drinking water samples were collected from different sources and localities of district East of Karachi. The concentration of the heavy metals i.e. Lead, Arsenic, Copper, Iron, Mercury, Chromium, Manganese, Nickel, Cadmium and Zinc were determined by Atomic Absorption Spectrophotometry. PH was estimated by pH meter. Total dissolved solids (TDS) were calculated by formula. These concentrations of heavy metals, pH and TDS were compared with the standards set by WHO. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water (Piped water, Hand pump water and Tanker water supply). Chromium was found to be raised in hand pump water. Arsenic and Mercury were not detected in any source of water. Copper, iron, manganese, cadmium and zinc were found to be within the safe limits in all the three sources of water. pH was found to be within the range of WHO recommended level in all the three sources of water. TDS was found to be elevated in hand pump water and tanker water. Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water in district East of Karachi.
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Poultry litter-based activated carbon for removing heavy metal ions in water.
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.
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Study on water vapor characteristic of typical heavy snowstorm case in Northern Xinjiang
NASA Astrophysics Data System (ADS)
Cui, C.; Zhang, J.
2017-12-01
Using the daily precipitation at 51 weather stations in the Northern Xinjiang from November to March during 2000—2012 and daily water vapor of NCEP/NCAR 6 h 1°×1° reanalysis data, the water vapor characteristics of 11 typical heavy snowstorm cases were studied. The result shows that the 11 cases are classified into 3 types: West of Northern Xinjiang and along Tianshan edge, north and east of Northern Xinjiang, west of Northern Xinjiang and west Tianshan. There are two main water vapor sources: Near the Mediterranean Sea, the Red Sea or near the Persian Gulf. There are two water vapor transport routes which are west, southwest and northwest, respectively. Water vapor from southwest route is more, that from northwest route is less. The top of water vapor is close to 300 hPa. The strongest water vapor transport level is between 650-750 hPa. Before the every occurrence of 11 heavy snowstorm processes, there are water vapor convergence between 600-1000 hPa in Northern Xinjiang.There are positive correlations between the snowstorm intensity and water vapor convergence between 600-1000 hPa, as well as the convergence strength, rang and duration time in Northern Xinjiang. Hence, some lowest values of the strongest water vapor transport, water vapor convergence and the upper and lower level jet streams are resented also and gave useful references for accurate heavy snowstorm forecasting.
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PARTIAL ECONOMIC STUDY OF STEAM COOLED HEAVY WATER MODERATED REACTORS
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1960-04-01
Steam-cooled reactors are compared with CAHDU for costs of Calandria tubes, pressure tubes. heavy water moderator, heavy water reflector, fuel supply, heat exchanger, and turbine generator. A direct-cycle lightsteam-cooled heavy- water-moderated pressure-tube reactor formed the basic reactor design for the study. Two methods of steam circulation through the reactor were examined. In both cases the steam was generated outside the reactor and superheated in the reactor core. One method consisted of a series of reactor and steam generator passes. The second method consisted of the Loeffler cycle and its modifications. The fuel was assumed to be natural cylindrical UO/sub 2/more » pellets sheathed in a hypothetical material with the nuclear properties of Zircaloy, but able to function at temperatures to 900 deg F. For the conditions assumed, the longer the rod, the higher the outlet temperature and therefore the higher the efficiency. The turbine cycle efficiency was calculated on the assumption that suitable steam generators are available. As the neutron losses to the pressure tubes were significant, an economic analysis of insulated pressure tubes is included. A description of the physics program for steam-cooled reactors is included. Results indicated that power from the steam-cooled reactor would cost 1.4 mills/ kwh compared with 1.25 mills/kwh for CANDU. (M.C.G.)« less
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VIEW OF TWO HEAVY WATER STORAGE TANKS (BEHIND SUPPORT COLUMNS ...
VIEW OF TWO HEAVY WATER STORAGE TANKS (BEHIND SUPPORT COLUMNS AND STEEL BEAMS), SUB-BASEMENT LEVEL -27, LOOKING SOUTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC
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NASA Astrophysics Data System (ADS)
Gupta, A.; Singh, P. J.; Gaikwad, D. Y.; Udupa, D. V.; Topkar, A.; Sahoo, N. K.
2018-02-01
An experimental setup is developed for the trace level detection of heavy water (HDO) using the off axis-integrated cavity output spectroscopy technique. The absorption spectrum of water samples is recorded in the spectral range of 7190.7 cm-1-7191.5 cm-1 with the diode laser as the light source. From the recorded water vapor absorption spectrum, the heavy water concentration is determined from the HDO and water line. The effect of cavity gain nonlinearity with per pass absorption is studied. The signal processing and data fitting procedure is devised to obtain linear calibration curves by including nonlinear cavity gain effects into the calculation. Initial calibration of mirror reflectivity is performed by measurements on the natural water sample. The signal processing and data fitting method has been validated by the measurement of the HDO concentration in water samples over a wide range from 20 ppm to 2280 ppm showing a linear calibration curve. The average measurement time is about 30 s. The experimental technique presented in this paper could be applied for the development of a portable instrument for the fast measurement of water isotopic composition in heavy water plants and for the detection of heavy water leak in pressurized heavy water reactors.
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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
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VIEW OF SOUTHERNMOST OF TWO HEAVY WATER STORAGE TANKS, LOCATED ...
VIEW OF SOUTHERN-MOST OF TWO HEAVY WATER STORAGE TANKS, LOCATED BEHIND SUPPORT COLUMN, WITH ADJACENT PIPING, LEVEL -27, LOOKING WEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC
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Kinetics of heavy metal inhibition of 1,2-dichloroethane biodegradation in co-contaminated water.
Arjoon, Ashmita; Olaniran, Ademola Olufolahan; Pillay, Balakrishna
2015-03-01
Sites co-contaminated with heavy metals and 1,2-DCA may pose a greater challenge for bioremediation, as the heavy metals could inhibit the activities of microbes involved in biodegradation. Therefore, this study was undertaken to quantitatively assess the effects of heavy metals (arsenic, cadmium, mercury, and lead) on 1,2-DCA biodegradation in co-contaminated water. The minimum inhibitory concentrations (MICs) and concentrations of the heavy metals that caused half-life doubling (HLDs) of 1,2-DCA as well as the degradation rate coefficient (k(1)) and half-life (t(½)) of 1,2-DCA were measured and used to predict the toxicity of the heavy metals in the water microcosms. An increase in heavy metal concentration resulted in a progressive increase in the t(½) and relative t(½) and a decrease in k(1). The MICs and HLDs of the heavy metals were found to vary, depending on the heavy metals type. In addition, the presence of heavy metals was shown to inhibit 1,2-DCA biodegradation in a dose-dependent manner, with the following order of decreasing inhibitory effect: Hg(2+) > As(3+) > Cd(2+) > Pb(2+). Findings from this study have significant implications for the development of bioremediation strategies for effective degradation of 1,2-DCA and other related compounds in wastewater co-contaminated with heavy metals. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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NASA Astrophysics Data System (ADS)
Szuster-Janiaczyk, Agnieszka; Zeuschner, Piotr; Noga, Paweł; Skrzypczak, Marta
2018-02-01
The study presents an analysis of water quality monitoring in terms of the content of heavy metals, which is conducted in three independent water supply systems in Poland. The analysis showed that the monitoring of heavy metals isn't reliable - both the quantity of tested water samples and the location of the monitoring points are the problem. The analysis of changes in water quality from raw water to tap water was possible only for one of the analysed systems and indicate a gradual deterioration of water quality, although still within acceptable limits of legal regulations.
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R. Bruce Merrifield and Solid-Phase Peptide Synthesis: A Historical Assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mitchell, A R
2007-12-04
Bruce Merrifield, trained as a biochemist, had to address three major challenges related to the development and acceptance of solid-phase peptide synthesis (SPPS). The challenges were (1) to reduce the concept of peptide synthesis on a insoluble support to practice, (2) overcome the resistance of synthetic chemists to this novel approach, and (3) establish that a biochemist had the scientific credentials to effect the proposed revolutionary change in chemical synthesis. How these challenges were met is discussed in this article.
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Modeling Adsorption Kinetics (Bio-remediation of Heavy Metal Contaminated Water)
NASA Astrophysics Data System (ADS)
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.
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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.
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New evaluation of thermal neutron scattering libraries for light and heavy water
NASA Astrophysics Data System (ADS)
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
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ERIC Educational Resources Information Center
Miller, Alexander David
2015-01-01
This dissertation considers the supportive and complementary relation between Mark Johnson's embodied realism and Bruce Lee's Jeet Kune Do as a philosophical practice. In exploring this relationship, the emphasis on one's embodiment condition and its relationship with metaphor and self-expression are the primary focus. First, this work involves…
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NASA Astrophysics Data System (ADS)
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
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On-line/on-site analysis of heavy metals in water and soils by laser induced breakdown spectroscopy
NASA Astrophysics Data System (ADS)
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).
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EFFECTS OF HEAVY WATER ON THE DEVELOPMENT OF POLIO VIRUS AS A FUNCTION OF TEMPERATURE (in French)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lwoff, A.; Lwoff, M.
1960-12-19
Heavy water medifies the speed of development and the infectious particle yield of the polio virus. These two effects are dependent on four factors: the temperature, the heavy water concentration, the moment when it is used, and the genotype of the virus stock. (tr-auth)
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Material Removes Heavy Metal Ions From Water
NASA Technical Reports Server (NTRS)
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.
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NASA Astrophysics Data System (ADS)
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.
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Trace Analysis of Heavy Metals in Ground Waters of Vijayawada Industrial Area
ERIC Educational Resources Information Center
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…
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Liu, Jiajia; Wang, Peifang; Wang, Chao; Qian, Jin; Hou, Jun
2017-01-01
The effects of water transfer projects on water channels and the receiving water involved need to be understood. In this research, the compositions and particle size distributions of surface sediment and the Cd, Cr, Cu, Ni, Pb, and Zn contents and distributions in the sediment along a water transfer route from the Wangyu River to Taihu Lake, China, were studied. The correlative relationship between the grain size trend and heavy metal content distribution suggested that heavy metals in Wangyu River sediment have affected the heavy metal contents of Taihu Lake sediment through silt and clay migrating in the transferred water. Enrichment factors and potential ecological risk values were calculated. Low levels of potential ecological risks are posed at 20 sampling sites in Taihu Lake, but higher-to-serious risks (potential ecological risk values >275) are posed at all Wangyu River sites. Toxicity of heavy metals (Cd, Cu, Zn, and Ni) in the Wangyu River sediments is more serious than those in the Taihu Lake, but is similar to the entrance of Gonghu Bay. Multivariate statistical analyses (Pearson correlation, cluster, and factor analyses) suggested heavy metals in the study area have many sources, and the relationships between particle migration and heavy metal contents indicated transferring water are likely to lead to adverse ecological risks being posed in Taihu Lake.
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Irrigation water quality influences heavy metal uptake by willows in biosolids.
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 <15% of initial values. A flushing treatment to remove excess salts was therefore not necessary. Irrigation had an impact on biosolids attributes such as salinity and pH, and that this had an influence on 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
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Astronaut Bruce McCandless shows mockup of occulting disc for Skylab exp.
1973-11-23
S73-37251 (23 November 1973) --- Astronaut Bruce McCandless II, left, shows off a mock-up of the occulting disc for the T025 Coronagraph Contamination Measurement Engineering and Technology Experiment to be used by the crewmen of the third manned Skylab mission (Skylab 4), now into their eighth day in Earth orbit. On the right is flight director Neil B. Hutchinson. The men are in the Mission Operations Control Room (MOCR) of the Mission Control Center (MCC) at Johnson Space Center. Photo credit: NASA
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NASA Astrophysics Data System (ADS)
Børresen, Hans Christofer
2012-12-01
The military campaign to deny Norwegian heavy water to Germany in World War II did not diminish as the threat posed by heavy water in German hands dwindled, mainly because of excessive security among the Allies. Signs that Albert Speer (1905-1981) had decided in 1942 to stop the German atomic-bomb project were kept secret and ignored. Prominent Allied advisers like Leif Tronstad (1903-1945) and even Niels Bohr (1885-1962) were not told about the plutonium path to a German atomic bomb. Physicists did not brief advisers, decision makers, and Allied officers on how many years Werner Heisenberg (1901-1976) would need to accumulate enough heavy water (deuterium oxide, D2O) for an Uranmachine and then to extract and process plutonium for an atomic bomb. Had the flow of information been better, the military raids on the Norwegian heavy-water plant at Vemork could have been timed better, and the more costly of them could have been averted altogether.
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Danil de Namor, Angela F; El Gamouz, Abdelaziz; Frangie, Sofia; Martinez, Vanina; Valiente, Liliana; Webb, Oliver A
2012-11-30
Contamination of water by heavy metals is a global problem, to which an inexpensive and simple solution is required. Within this context the unique properties of diatomite and its abundance in many regions of the world have led to the current widespread interest in this material for water purification purposes. Defined sections on articles published on the use of raw and modified diatomite for the removal of heavy metal pollutants from water are critically reviewed. The capability of the materials as extracting agents for individual species and mixtures of heavy metals are considered in terms of the kinetics, the thermodynamics and the recyclability for both, the pollutant and the extracting material. The concept of 'selectivity' for the enrichment of naturally occurring materials such as diatomite through the introduction of suitable functionalities in their structure to target a given pollutant is emphasised. Suggestions for further research in this area are given. Copyright © 2012 Elsevier B.V. All rights reserved.
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Heavy metals in water, sediments, plants and fish of Kali Nadi U. P. (India)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ajmal, M.; Uddin, R.; Khan, A.U.
1988-01-01
The distribution of heavy metals viz., Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, plants and fish samples collected from the Kali Nadi (India) have been determined. The studies have shown that there was considerable variation in the concentration of heavy metals from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wastes being added to the river at different places. The orders of the concentration of heavy metals in water, sediments, plants (Eicchornia crassipes) and fish (Heteropnuestes fossilis) were Fe > Znmore » > Cu > Mn > Cr > Ni > Pb > Co > Cd; Fe > Zn > Mn > Ni > Cr > Co > Cu > Pb > Cd; Fe > Mn > Zn > Cu > Ni > Co > Pb > Cr > Cd and Fe > Zn > Mn > Ni > Pb >Co > Cr > Cu > Cd, respectively.« less
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Jin, Jian; Li, Xiaodong; Chi, Yong; Yan, Jianhua
2010-12-01
This study investigated the process of aluminosilicate formation in medical waste incinerator fly ash containing large amounts of heavy metals and treated with alkaline compounds at 375 degrees C and examined how this process affected the mobility and availability of the metals. As a consequence of the treatments, the amount of dissolved heavy metals, and thus their mobility, was greatly reduced, and the metal leaching concentration was below the legislative regulations for metal leachability. Moreover, this process did not produce a high concentration of heavy metals in the effluent. The addition of alkaline compounds such as sodium hydroxide and sodium carbonate can prevent certain heavy metal ions dissolving in water. In comparison with the alkaline-free condition, the extracted concentrations of As, Mn, Pb, Sr and Zn were decreased by about 51.08, 97.22, 58.33, 96.77 and 86.89% by the addition of sodium hydroxide and 66.18, 86.11, 58.33, 83.87 and 81.91% by the addition of sodium carbonate. A mechanism for how the formation of aluminosilicate occurred in supercritical water and affected the mobility and availability of the heavy metals is discussed. The reported results could be useful as basic knowledge for planning new technologies for the hydrothermal stabilization of heavy metals in fly ash.
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ERIC Educational Resources Information Center
Haythornthwaite, Caroline
2014-01-01
A career spent in research, teaching, and engagement with community entails a lifetime of assemblage of meaning from people, resources, technologies and experience. In his work, Bertram (Chip) Bruce has long engaged with how we create such an assemblage of meaning from our formal and found learning, and from the "lived experience" of…
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ERIC Educational Resources Information Center
Davis, Alan; Mitchell, Kara; Dray, Barbara; Keenan, Tracy
2012-01-01
Working in a research collaborative between Denver Public Schools and the University of Colorado Denver, the authors selected Bruce Randolph High School (BRHS) as a case study because of its growth on state academic achievement tests and because of its multilingual learners. After a difficult beginning, BRHS has established an inclusive culture of…
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Marinko Sremac; Joseph Elkinton; Adam Porter
2011-01-01
Elkinton et. al. recently completed a survey of northeastern North America for the newly invasive winter moth, Operophtera brumata L. The survey used traps baited with the winter moth pheromone, which consists of a single compound also used by Bruce spanworm, O. bruceata (Hulst), the North American congener of winter moth. Our...
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Detection of heavy metals in water in Negeri Sembilan, Malaysia: From source to consumption
NASA Astrophysics Data System (ADS)
Khalaf, Baydaa; Abdullah, Md. Pauzi; Tahrim, Nurfaizah Abu
2018-04-01
Drinking water should be free from harmful levels of impurities, such as heavy metals. The aim of this study is to investigate the heavy metals concentrations in a water reticulation system of Negeri Sembilan. 25 stations were selected along Sungai Linggi (upstream of intake point) and through there reticulation system of Sungai Linggi Water Treatment Plant encompassing raw water through to the last point of use. Sampling activities were carried out in June and July 2016. The samples taken were analysed for heavymetals using an Inductively Coupled Plasma - Optical Emission Spectrometer (ICP-OES). In addition other water quality parameters were measured in situ (pH, water temperature, conductivity and dissolved oxygen) and analysed in the laboratory (BOD, COD, TSS, NH3-N, TOC and residual chlorine). The results showed a high level of Ca in the distribution system, while in the treatment plant it was normal, as well as Fe is decreased. Meanwhile Mn is decreased after treatment processes. The concentrations of DO and temperature in the tap water exceeded the standard concentrations.
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Evaluation of Data on Solubility of Simple Apolar Gases in Light and Heavy Water at High Temperature
NASA Astrophysics Data System (ADS)
Prini, Roberto Fernández; Crovetto, Rosa
1989-07-01
The solubility data of apolar gases in light and heavy water over the temperature range covered experimentally have been evaluated, laying particular emphasis to the region above the normal boiling points of the solvents. The systems that have been included in this work are the inert gases and CH4 in light water and heavy water, H2, O2, N2, and C2H6 in light water and D2 in heavy water. Data in the original sources have been brought to the same footing by calculating from the raw experimental data P, T, and x when they were not reported by the author. This step is considered necessary to assess critically the available sets of data. The temperature dependence of Henry's constants for all the binary systems have been expressed in terms of two different polynomial equations. The formulations presented are discussed and the limits of application given.
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Zhang, Ling; Shi, Zhen; Zhang, Jingping; Jiang, Zhijian; Wang, Fei; Huang, Xiaoping
2016-05-01
Heavy metal concentrations and distribution were studied in sediments, seawater, and molluscs, and the possible heavy metal sources in the coastal waters of Guangdong Province, South China were discussed. The results showed that the concentrations of Cu, Pb, Zn, and Cr in sediments in eastern coastal waters were generally higher than those in the western coastal waters. However, concentrations of most metals in seawater and molluscs in western waters were higher than in the eastern waters, which was tightly related to the local economics and urbanization development, especially, the different industrial structure in two regions. The main heavy metal sources were attributed to the industrial and agricultural effluent, domestic sewage, and even waste gas. Furthermore, heavy metal contamination assessment indicated that high contamination levels of Cd, Zn, and Pb occurred in sediments in local areas, especially in the bays and harbors. The metal accumulation levels by molluscs ranked following the order of Cd > Cu > As > Zn > Pb > Cr, and the ecological risks introduced by heavy metals in different areas were in the order of Zhanjiang > Yangmao > Shantou > Shanhui.
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Neutron production by stopping 55 MeV deuterons in carbon and heavy water
NASA Astrophysics Data System (ADS)
Lhersonneau, G.; Malkiewicz, T.; Jones, P.; Ketelhut, S.; Trzaska, W. H.
2012-09-01
Neutron production by stopping 55 MeV deuterons in thick carbon and heavy-water targets has been measured by the activation method. The geometry was close to the one defined for the SPIRAL2 uranium-carbide target in the initial phase. A comparative method for obtaining the neutron flux has been used and is presented in detail. The neutron flux generated by 55 MeV deuterons on carbon is 2.3 times the flux at the deuteron energy of 40 MeV. The flux further increases by a factor 1.4 when using a heavy-water target. These results are discussed in the context of an energy upgrade of the SPIRAL2 driver accelerator.
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Removal of radioactive materials and heavy metals from water using magnetic resin
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.
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Fischer, Sophia; Soyez, Katja; Gurtner, Sebastian
2015-05-01
Research testing the concept of decision-making styles in specific contexts such as health care-related choices is missing. Therefore, we examine the contextuality of Scott and Bruce's (1995) General Decision-Making Style Inventory with respect to patient choice situations. Scott and Bruce's scale was adapted for use as a patient decision-making style inventory. In total, 388 German patients who underwent elective joint surgery responded to a questionnaire about their provider choice. Confirmatory factor analyses within 2 independent samples assessed factorial structure, reliability, and validity of the scale. The final 4-dimensional, 13-item patient decision-making style inventory showed satisfactory psychometric properties. Data analyses supported reliability and construct validity. Besides the intuitive, dependent, and avoidant style, a new subdimension, called "comparative" decision-making style, emerged that originated from the rational dimension of the general model. This research provides evidence for the contextuality of decision-making style to specific choice situations. Using a limited set of indicators, this report proposes the patient decision-making style inventory as valid and feasible tool to assess patients' decision propensities. © The Author(s) 2015.
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Supercritical water treatment of heavy metal and arsenic metalloid-bioaccumulating-biomass.
Li, Jianxin; Chen, Jinbo; Chen, Shan
2018-08-15
Hyperaccumulator biomass, as a promising resource for renewable energy that can be converted into valuable fuel productions with high conversion efficiency, must be considered as hazardous materials and be carefully treated before further reuse due to the high contents of heavy metals. In this study, Pteris vittata L., an As-hyperaccumulator biomass was treated by an effective and environmental friendly method-supercritical water gasification (SCWG) using a bench-scale batch reactor. The contents of heavy metals (Cd, Pb and Zn) and arsenic metalloid in solid, liquid and gaseous products during SCWG process were thoroughly investigated. The speciation fractions including exchangeable, reducible, oxidizable and residual fractions of each heavy metal as the proportion of the total contents in solid residue were presented and the transformations trend of these heavy metals during the SCWG process was especially demonstrated. The significant operating parameters, including reaction temperature (395-445 °C), pressure (21-27 MPa) and residence time (0-40 min) were varied to explore their effects on the contents and forms. Moreover, the environmental risks of heavy metals in solid residues were evaluated based on risk assessment code, taking into consideration the speciation fractions and bioavailability. It was highlighted that although heavy metals particularly Pb and Zn tended to accumulate in solid residues with a maximum increment of about 50% in the total content, they were mostly converted to more stable oxidizable and residual fractions, and thus the ecotoxicity and bioavailability were greatly mitigated with no obvious increase in direct toxicity fractions. Each tested heavy metal presented no or low risk to the environments after SCWG treatments, meaning that the environmental pollution levels were markedly reduced with no or low risk to the environment. This study highlights the remarkable ability of SCWG for the heavy metal stabilization. Copyright
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The effects of fire temperatures on water soluble heavy metals.
NASA Astrophysics Data System (ADS)
Pereira, P.; Ubeda, X.; Martin, D. A.
2009-04-01
Fire ash are majority composed by base cations, however the mineralized organic matter, led also available to transport a higher quantity of heavy metals that potentially could increase a toxicity in soil and water resources. The amount availability of these elements depend on the environment were the fire took place, burning temperature and combusted tree specie. The soil and water contamination from fire ash has been neglected, because the majority of studies are focused on base cations dynamic. Our research, beside contemplate major elements, is focused in to study the behavior of heavy metals released from ash slurries created at several temperatures under laboratory environment, prescribed fires and wildland fires. The results presented in these communication are preliminary and study the presence of Aluminium (Al3+), Manganese (Mn2+), Iron (Fe2+) and Zinc (Zn2+) of ash slurries generated in laboratory environment at several temperatures (150°, 200°, 250°, 300°, 350°, 400°,450°, 500°, 550°C) from Quercus suber, Quercus robur, Pinus pinea and Pinus pinaster and from a low medium temperature prescribed fire in a forest dominated Quercus suber trees. We observed that ash produced at lower and medium temperatures (<300-400°C) released in water higher contents of Al3+ than unburned sample, especially in Quercus species and Mn2+ in Pinus ashes. Fe2+ and Zn2+ showed a reduced concentration in test solution in relation to unburned sample at all temperatures of exposition. In the results obtained from prescribed fire, we identify a higher release of Al3+ and a decrease of the remain elements. The solubilization of these elements are related with pH levels and ash calcite content, because their ability to capture ions in solution. Moreover, the amount and the type of ions released in relation to unburned sample vary in each specie. In this study Al3+ release is related with Quercus species and Mn2+ with Pinus species. Fire ashes can be an environmental problem
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Joseph Elkinton; Natalie Leva; George Boettner; Roy Hunkins; Marinko. Sremac
2011-01-01
Elkinton et al. recently completed a survey of northeastern North America for the newly invasive winter moth, Operophtera brumata L. The survey used traps baited with the winter moth pheromone, which, as far as it is known, consists of a single compound that is also used by Bruce spanworm, the North American congener of winter moth, O....
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Removal of radioactive materials and heavy metals from water using magnetic resin
Kochen, R.L.; Navratil, J.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. 9 figs.
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Nowrouzi, Mohsen; Mansouri, Borhan; Nabizadeh, Sahar; Pourkhabbaz, Alireza
2014-02-01
This study determined the concentration of heavy metals (Al, Cr, Cu, and Zn) in water and sediments at nine sites in the Hara biosphere reserve of southern Iran during the summer and winter 2010. Determination of Al, Cr, Cu, and Zn in water was carried out by graphite furnace atomic absorption spectrometer (Shimadzu, AA 610s) and in sediment by flame atomic absorption spectrometer (Perkin Elmer, AA3030). Results showed that the heavy metal concentrations in the water samples decreased in the sequence of Zn > Al > Cu > Cr, while in sediment samples were Cr > Zn > Cu > Al. Data analysis indicated that with the exception of Al, there was a Pearson's correlation coefficient between pH and Cu, Zn, and Cr at α = 0.01, 0.05, and 0.001 in sediment (in winter), respectively. There were also significant differences between heavy metals of Cr, Cu, and Zn during the two seasons (p < 0.001) in the water and sediment.
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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
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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.
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Production of heavy water in India
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fareeduddin, S.
From symposium on nuclear science and engineering; Bombay, India (13 Mar 1973). To meet the requirements of heavy water for the power reactors now under construction and those being planned, a program for providing adequate production capacity has been started. Various processes have been surveyed and the factors which have been considered in the choice of the processes adopted in India are presented. The H/sub 2/S--H/sub 2/0 exchange process adopted for the plant being set up at Kota and the ammoria--hydrogen exchange process adopted for the Baroda plant are briefly described. The status of the various plants under construction hasmore » been presented. The operating experience of the Nangal plant during the last ten years is included. (auth)« less
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Irrigation water quality in southern Mexico City based on bacterial and heavy metal analyses
NASA Astrophysics Data System (ADS)
Solís, C.; Sandoval, J.; Pérez-Vega, H.; Mazari-Hiriart, M.
2006-08-01
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.
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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.
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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.
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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; Pb 2+ , Cu 2+ , and Cd 2+ 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.
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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
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Effect of polluted water on soil and plant contamination by heavy metals in El-Mahla El-Kobra, Egypt
NASA Astrophysics Data System (ADS)
Kasem Mahmoud, Esawy; Ghoneim, Adel Mohamed
2016-04-01
The discharge of untreated waste water in Zefta drain and drain no. 5 is becoming a problem for many farmers in the El-Mahla El-Kobra area, Egypt. The discharged water contains high levels of contaminants considered hazardous to the ecosystem. Some plants, soil, water, and sediment samples were collected from the El-Mahla El-Kobra area to evaluate the contamination by heavy metals. The results showed that the heavy metals, pH, sodium adsorption ratio (SAR), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) in the water of Zefta drain and drain no. 5 exceeded permissible limits for irrigation. In rice and maize shoots grown in soils irrigated by contaminated water from Zefta drain and drain no. 5, the bioaccumulation factors for Cd, Pb, Zn, Cu, and Mn were higher than 1.0. The heavy metals content of irrigated soils from Zefta drain and drain no. 5 exceeded the upper limit of background heavy metals. In this study, the mean contaminant factor values of the drain no. 5 sediments revealed that Zn, Mn, Cu, Cd, Pb, and Ni > 6, indicating very high contamination. The bioaccumulation coefficient values of Cynodon dactylon, Phragmites australis, and Typha domingensis aquatic plants growing in Zefta drain are high. These species can be considered as hyperaccumulators for the decontamination of contaminated water.
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Electromyogram as a measure of heavy metal toxicity in fresh water and salt water mussels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kidder, G.W. III; McCoy, A.A.
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.
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Ahsan, Muhammad; Younis, Adnan; Jaskani, Muhammad Jafar; Tufail, Aasma; Riaz, Atif; Schwinghamer, Timothy; Tariq, Usman; Nawaz, Fahim
2018-09-15
Wastewater is an alternative to traditional sources of renewable irrigation water in agriculture, particularly in water-scarce regions. However, the possible risks due to heavy metals accumulation in plant tissues are often overlooked by producers. The present study aimed to identify heavy metals-induced structural modifications to roots of scented Rosa species that were irrigated with water of marginal quality. The chemical and mineral contents from the experimental irrigation canal water (control) and treated wastewater were below the limits recommended by the Pakistan Environmental Protection Agency (Pak-EPA) for medicinal plants. The experimentally untreated wastewater contained electrical conductivity (EC), chemical oxygen demand (COD), biological oxygen demand (BOD), and heavy metals (Co, Cu, Cd, Pb) that were above the recommended limits. The responses by wastewater-treated Rosa species (Rosa damascena, R. bourboniana, R. Gruss-an-Teplitz, and R. centifolia) were evaluated. The experimental data revealed that treated wastewater significantly increased the thickness of collenchyma (cortex and pith) and parenchyma tissues (vascular bundle, xylem, and phloem) of R. Gruss-an-Teplitz. Root dermal tissues (epidermis) of R. bourboniana also responded to treated wastewater. R. damascena and R. centifolia were the least affected species, under the experimental irrigation conditions. Collenchyma and dermal tissues were thicker in R. damascena and R. Gruss-an-Teplitz under untreated wastewater conditions. In parenchyma tissues, vascular bundles were thicker in R. damascena in untreated wastewater conditions, while the xylem and phloem of R. Gruss-an-Teplitz were thicker where treated wastewater was applied. In tissues other than the vascular bundle, the differences in anatomical metrics due to the experimental irrigation treatments were greater during the second year of the experiment than in the first year. The contents of metals other than chromium in the roots and
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Urushadze, Teo
2018-01-01
Water quality contamination by heavy metal pollution has severe effects on public health. In the Mashavera River Basin, an important agricultural area for the national food system in Georgia (e.g., vegetable, dairy and wine production), water contamination has multiple influences on the regional and country-wide health. With new industrial activities in the region, sediment extraction, and discharge of untreated wastewater into the river, its tributaries and irrigation canals, a comprehensive study of water quality was greatly needed. This study examined sediment and water samples from 17 sampling sites in the Mashavera River Basin during the high and low precipitation seasons. The results were characterized utilizing the Geo-accumulation Index (Igeo), Enrichment Factor (EF), Pollution Load index (PLI), Contamination Factor (CF) and Metal Index (MI). According to the CFs, Cu > Cd > Zn > Pb > Fe > Mn > Ni > Cr > Hg is the descending order for the content of all observed heavy metals in sediments collected in both seasons. Fe and As were additionally examined in water samples. Overall, As, Cd and Pb, all highly toxic elements, were found in high concentrations in downstream sample sites. According to these results, comprehensive monitoring with narrow intervals between sampling dates, more sample sites along all waterways, and proximate observation of multiple trace metal elements are highly recommended. Moreover, as the part of the water quality governance system, an immediate and sustainable collective action by all stakeholders to control the pollution level is highly recommended, as this issue is linked to the security of the national food system and poses a local public health risk. PMID:29597320
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Maleki, Afshin; Amini, Hassan; Nazmara, Shahrokh; Zandi, Shiva; Mahvi, Amir Hossein
2014-01-01
Heavy metals are ubiquitous elsewhere in nature and their measurement in environment is necessary to develop health management strategies. In this study, we aimed to find out concentrations and spatial patterns of heavy metals in main farms of Sanandaj in Kurdistan, Iran. Over May to October 2012, six farms were selected to analyze concentrations and spatial patterns of several heavy metals, namely aluminum (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in their soil, irrigation water, and edible vegetables. Overall, 36 samples of soil and water and 72 samples of vegetables including coriander (Coriandrum sativum), dill (Anethum graveolens), radish (Raphanus sativus) root and radish leaf were collected. The concentrations of metals were determined by inductively coupled plasma optical emission spectrometry. The spatial surfaces of heavy metals were created using geospatial information system. The order of metals in soil was Al > Zn > Ni > Cu > Cr > Pb > Co > As > Cd while in water it was Cr > Co > Zn > Pb > Cu > Ni > Al = As = Cd. The order of heavy metals in vegetables was Al > Zn > Cu > Cr > Ni > Pb > Co > As > Cd. Totally, the minimum concentrations of Al, Cu, Pb, and Zn were found in radish root while the maximum of Al, Co, Cr, and Ni were found in radish leaf. The minimum concentrations of Cd and Cr and maximum concentrations of Cu and Zn were also deciphered in dill. Noteworthy, coriander had the minimum concentrations of Co and Ni. The concentrations of Cr and Pb in vegetables were more than maximum allowable limits of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). In summary, albeit the concentrations of heavy metals in soil and water samples were below FAO and the WHO standards, vegetables were contaminated by chromium and lead.
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Hou, Ying-Chen Claire; Chittaranjan, Suganthi; Barbosa, Sharon González; McCall, Kimberly; Gorski, Sharon M
2008-09-22
A complex relationship exists between autophagy and apoptosis, but the regulatory mechanisms underlying their interactions are largely unknown. We conducted a systematic study of Drosophila melanogaster cell death-related genes to determine their requirement in the regulation of starvation-induced autophagy. We discovered that six cell death genes--death caspase-1 (Dcp-1), hid, Bruce, Buffy, debcl, and p53-as well as Ras-Raf-mitogen activated protein kinase signaling pathway components had a role in autophagy regulation in D. melanogaster cultured cells. During D. melanogaster oogenesis, we found that autophagy is induced at two nutrient status checkpoints: germarium and mid-oogenesis. At these two stages, the effector caspase Dcp-1 and the inhibitor of apoptosis protein Bruce function to regulate both autophagy and starvation-induced cell death. Mutations in Atg1 and Atg7 resulted in reduced DNA fragmentation in degenerating midstage egg chambers but did not appear to affect nuclear condensation, which indicates that autophagy contributes in part to cell death in the ovary. Our study provides new insights into the molecular mechanisms that coordinately regulate autophagic and apoptotic events in vivo.
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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 (m 2 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
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Azeez, L; Salau, A K; Adewuyi, S O; Osineye, S O; Tijani, K O; Balogun, R O
2015-12-20
This study evaluated the pH, heavy metals and volatile organic compounds (VOCs) in Osun river water. It also evaluated its safety in rats. Heavy metals were determined by atomic absorption spectrophotometry (AAS) while VOCs were determined by gas chromatography coupled with flame ionization detector (GC-FID). 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 the permissible limits of Standards Organization of Nigeria (SON) and World Health Organization (WHO) respectively. Rats exposed to Osun river water for three weeks had increased WBC, thiobarbituric acid reactive substances (TBARS), serum proteins and serum aminotransferases. There were also significant decreases in HCT, PLT, liver aminotransferases and liver glutathione compared to the control. These results show that the pollutants in Osun river water are capable of inducing hematological imbalance and liver cell injury. The toxicity induced in blood was sex-dependent affecting female rats more than male rats.
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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.
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A Review: Advances on Absorption of Heavy Metals in the Waste Water by Biochar
NASA Astrophysics Data System (ADS)
Chen, Hao; Xie, Anbin; You, Shaohong
2018-01-01
Biochar as a new type of adsorbent, its physical and chemical characteristics and adsorption of heavy metal has been widely studied. Based on the current studies, the article reviewed the main characteristics of biochar, its influencing factors (preparation temperature, feed stocks, functional group et.) on adsorption of heavy metals in water and its mechanism of adsorption (ion exchange adsorption, complexation, precipitation sedimentation et.). Briefly summarize unresolved issues for potential applications of biochar in the future.
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Lysimeter Study of Plant Water Uptake in a Model Forest Ecosystem on Heavy Metal Contaminated Soil
NASA Astrophysics Data System (ADS)
Menon, M.; Abbaspour, K.; Schulin, R.; Oswald, S.
2003-04-01
We have been investigating the impact of heavy metal stress on the water regime of young forest ecosystems grown in 32 open top lysimeters (3 m in diameter and 1 m deep). The factorial treatments of the lysimeters include variations of rainwater acidity (acidic, ambient rain), subsoil type (acidic, calcareous), and soil contamination (with and without copper, zinc and cadmium in the top 20 cm). Each lysimeter was planted in spring of 2000 with the same selection of trees and herbaceous plants. All lysimeters are equipped with tensiometers for monitoring of pressure head and time domain reflectometry for measuring of water content. Irrigation was applied equally to all lysimeters through sprinkler devices. Drainage water was collected by means of canisters installed at the bottom of the lysimeters, and thus evapotranspiration could be calculated through water balancing. We monitored the water regime for two years including an imposed drought period. Significantly more water was extracted from the calcareous than the acidic subsoil. The water potential measurements show that also the heavy metal polluted topsoil had a significant influence on the water regime. Metal stress was particularly evident under reduced irrigation. We suspect that the roots were damaged in the contaminated topsoil. In contrast to the subsoil type, heavy metal pollution did not produce a significant effect on evapotranspiration (ET) though, and neither did acidic rain. Pot experiments confirmed that in presence of clean subsoil plants compensated for metal stress in contaminated topsoil by shifting their root activity from contaminated to uncontaminated zones.
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Tunc, Talip; Sahin, Ustun
2016-04-01
The objective of this 2-year field study was to evaluate the effects of drip irrigation with urban wastewaters reclaimed using primary (filtration) and secondary (filtration and aeration) processes on red cabbage growth and fresh yield, heavy metal content, water use and efficiency and soil chemical properties. Filtered wastewater (WW1), filtered and aerated wastewater (WW2), freshwater and filtered wastewater mix (1:1 by volume) (WW3) and freshwater (FW) were investigated as irrigation water treatments. Crop evapotranspiration decreased significantly, while water use efficiency increased under wastewater treatments compared to FW. WW1 treatment had the lowest value (474.2 mm), while FW treatments had the highest value (556.7 mm). The highest water use efficiency was found in the WW1 treatment as 8.41 kg m(-3), and there was a twofold increase with regard to the FW. Wastewater irrigation increased soil fertility and therefore red cabbage yield. WW2 treatment produced the highest total fresh yield (40.02 Mg ha(-1)). However, wastewater irrigation increased the heavy metal content in crops and soil. Cd content in red cabbage heads was above the safe limit, and WW1 treatment had the highest value (0.168 mg kg(-1)). WW3 treatment among wastewater treatments is less risky in terms of soil and crop heavy metal pollution and faecal coliform contamination. Therefore, WW3 wastewater irrigation for red cabbage could be recommended for higher yield and water efficiency with regard to freshwater irrigation.
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Toenail as a biomarker of heavy metal exposure via drinking water: a systematic review.
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.
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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.
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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. PMID:22590550
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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.
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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.
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Seiler, Claudia; Berendonk, Thomas U
2012-01-01
The use of antibiotic agents as growth promoters was banned in animal husbandry to prevent the selection and spread of antibiotic resistance. However, in addition to antibiotic agents, heavy metals used in animal farming and aquaculture might promote the spread of antibiotic resistance via co-selection. To investigate which heavy metals are likely to co-select for antibiotic resistance in soil and water, the available data on heavy metal pollution, heavy metal toxicity, heavy metal tolerance, and co-selection mechanisms was reviewed. Additionally, the risk of metal driven co-selection of antibiotic resistance in the environment was assessed based on heavy metal concentrations that potentially induce this co-selection process. Analyses of the data indicate that agricultural and aquacultural practices represent major sources of soil and water contamination with moderately to highly toxic metals such as mercury (Hg), cadmium (Cd), copper (Cu), and zinc (Zn). If those metals reach the environment and accumulate to critical concentrations they can trigger co-selection of antibiotic resistance. Furthermore, co-selection mechanisms for these heavy metals and clinically as well as veterinary relevant antibiotics have been described. Therefore, studies investigating co-selection in environments impacted by agriculture and aquaculture should focus on Hg, Cd, Cu, and Zn as selecting heavy metals. Nevertheless, the respective environmental background has to be taken into account.
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Seiler, Claudia; Berendonk, Thomas U.
2012-01-01
The use of antibiotic agents as growth promoters was banned in animal husbandry to prevent the selection and spread of antibiotic resistance. However, in addition to antibiotic agents, heavy metals used in animal farming and aquaculture might promote the spread of antibiotic resistance via co-selection. To investigate which heavy metals are likely to co-select for antibiotic resistance in soil and water, the available data on heavy metal pollution, heavy metal toxicity, heavy metal tolerance, and co-selection mechanisms was reviewed. Additionally, the risk of metal driven co-selection of antibiotic resistance in the environment was assessed based on heavy metal concentrations that potentially induce this co-selection process. Analyses of the data indicate that agricultural and aquacultural practices represent major sources of soil and water contamination with moderately to highly toxic metals such as mercury (Hg), cadmium (Cd), copper (Cu), and zinc (Zn). If those metals reach the environment and accumulate to critical concentrations they can trigger co-selection of antibiotic resistance. Furthermore, co-selection mechanisms for these heavy metals and clinically as well as veterinary relevant antibiotics have been described. Therefore, studies investigating co-selection in environments impacted by agriculture and aquaculture should focus on Hg, Cd, Cu, and Zn as selecting heavy metals. Nevertheless, the respective environmental background has to be taken into account. PMID:23248620
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NASA Astrophysics Data System (ADS)
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.
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Sachan, Sanjay; Singh, S K; Srivastava, P C
2007-10-01
Accumulation of heavy metals in soil-water-plant continuum as a result of irrigation with metals contaminated effluent has been studied. Effluents being used for irrigating agricultural fields had normal pH 7.3-7.5, high Cr and Cl content as per the prescribed standards for irrigation. Among the heavy metals, buildup of total Iron was highest (9 times) and that of cadmium (1.3 times) was lowest in effluent irrigated soil as compared to tubewell irrigated soils. In most of the hand pump water samples, Pb, Cd and Cr were above the permissible limits for drinking. Bioaccumulation of Pb and Cr in vegetables was found to be above the critical concentrations for plant growth while Pb and Cd were above the prescribed limit in the diet of animals. Most of the heavy metals were above the maximum allowable limit in soil.
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Xu, Jiang; Cao, Zhen; Zhang, Yilin; Yuan, Zilin; Lou, Zimo; Xu, Xinhua; Wang, Xiangke
2018-03-01
Carbon-based nanomaterials, especially carbon nanotubes and graphene, have drawn wide attention in recent years as novel materials for environmental applications. Notably, the functionalized derivatives of carbon nanotubes and graphene with high surface area and adsorption sites are proposed to remove heavy metals via adsorption, addressing the pressing pollution of heavy metal. This critical revies assesses the recent development of various functionalized carbon nanotubes and graphene that are used to remove heavy metals from contaminated water, including the preparation and characterization methods of functionalized carbon nanotubes and graphene, their applications for heavy metal adsorption, effects of water chemistry on the adsorption capacity, and decontamination mechanism. Future research directions have also been proposed with the goal of further improving their adsorption performance, the feasibility of industrial applications, and better simulating adsorption mechanisms. Copyright © 2017 Elsevier Ltd. All rights reserved.
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NASA Technical Reports Server (NTRS)
Scofield, Rod; Vicente, Gilberto; Hodges, Mike
2000-01-01
This Tech Report summarizes years of study and experiences on using GOES Water vapor (6.7 micron and precipitable water) and Special Sensor Microwave Imager (SSM/1) from the Defense Meteorological Satellite Program (DMSP) derived Precipitable Water (PNAI) for detecting environments favorable for convectively produced flash floods. An emphasis is on the moisture. upper air flow, and equivalent potential temperature (Theta(sub e)) patterns that lead to devastating flood events. The 15 minute 6.7 micron water vapor imagery is essential for tracking middle to upper tropospheric disturbances that produce upward vertical motion and initiate flash flood producing systems. Water vapor imagery at 6.7 micron is also used to detect surges of upper level moisture (called tropical water vapor plumes) that have been associated with extremely heavy rainfall. Since the water vapor readily depicts lifting mechanisms and upper level moisture, water vapor imagery is often an excellent source of data for recognizing patterns of heavy precipitation and flash floods. In order to analyze the depth of the moisture, the PW aspects of the troposphere must be measured. The collocation (or nearby location) of high values ofP\\V and instability are antecedent conditions prior to the flash flood or heavy rainfall events. Knowledge of PW magnitudes have been used as thresholds for impending flash flood events, PW trends are essential in flash flood prediction. Conceptual models and water vapor products are used to study some of the characteristics of convective systems that occurred over the United States of America (USA) during the summer of 1997 and the 1997-1998 El Nino. P\\V plumes were associated with most of the \\vest coast heavy precipitation events examined during the winter season of 1997 - 1998, In another study, conducted during the summer season of 1997. results showed that the collocation of water vapor (6.7 micron) and P\\N' plumes possessed higher correlations with predicted
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NASA Astrophysics Data System (ADS)
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.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lavillaureix, J.; Reeb, E.; Surjus, A.
1961-03-20
The multiplication of West Nile, Coxsackie B3, and polio type II viruses is considerably increased if they are inoculated on cells cultivated in the presence of heavy water 5 hr before inoculation. The viral infection can not evolve in the presence of heavy water. (tr-auth)
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Analysis of Heavy Metal Content (Pb) on Waters and Fish at The Floating Cages BPPP Ambon
NASA Astrophysics Data System (ADS)
Wattimena, Rachel L.; Selanno, Debby A. J.; Tuhumury, Semuel F.; Tuahatu, Juliana W.
2018-02-01
Coastal waters play important roles due to highly in natural resources and developing of environmental services. However, there are highly intensity of natural resources utilization, environment and settlement. Consequently, environment and natural resources would be degraded such as in the Ambon Bay. One of the potency at the Ambon Bay is mariculture area namely the floating cages (KJA) which belongs to Fisheries education and training (BPPP) Ambon. The research aimed to analyze physical-chemical of waters (temperature, pH, salinity and current speed), to analyze heavy metal concentration (Pb) on water and fish from floating cages (KJA) and to analyze waters pollution status at KJA BPPP Ambon. The average salinity of each floating cage ranged from 30.09 - 30.34°C, pH ranged from 8.03 - 8.44, salinity ranged from 31.36 - 33.34 PSU, and current speed at spring tide ranged from 0.5 - 55.8 Cm/sec while neap tide ranged from 0.1 - 9.8 Cm/sec. Heavy metal concentration (Pb) on waters was below the standard for waters quality and the average concentration was 0.002 mg/l. Whilst, the heavy metal concentration (Pb) on fishes was below standard for floating cages (floating cages 2-6) which was 0.05 and 0.17mg/l. Otherwise, floating cage 1 had been above maximum standard for fish food and its processing following SNI 7387:2009 (0.3mg/l) which was 0.31 mg/l. The status of waters pollution at KJA BPPP Ambon belonged to C class and could be categorized as moderate based on standard for waters quality issued by State Ministerial Decree for the Environment No. 51 Year 2004.
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Annibaldi, Anna; Illuminati, Silvia; Truzzi, Cristina; Scarponi, Giuseppe
2018-02-01
Heavy metal concentrations (cadmium, lead, and copper) in spring, tap, and bottled waters of the Sibylline Mountains National Park (central Italy) were investigated using square wave anodic stripping voltammetry from 2004 to 2011. The mean (±SD) concentrations detected (1.3 ± 0.4 ng L -1 cadmium, 14 ± 6 ng L -1 lead, and 0.16 ± 0.10 μg L -1 copper) were below the limits stipulated by Italian and European legislation for drinking and natural mineral water. In the three studied areas of the park (Mount Bove north, Mount Bove south, and springs of River Nera) with very few exceptions, both mineral waters bottled in the area and aqueduct waters from public fountains had approximately the same metal concentrations as did the spring waters from which they were derived. Conversely, substantially higher metal concentrations were found at some sites in private houses, which may be due to release of metals from old metal pipes. At the time of this study, waters of Sibylline Mountains National Park were of good quality, and no influence of the bottling process on heavy metal concentrations was found.
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Detection of trace heavy metal ions in water by nanostructured porous Si biosensors.
Shtenberg, Giorgi; Massad-Ivanir, Naama; Segal, Ester
2015-07-07
A generic biosensing platform, based on nanostructured porous Si (PSi), Fabry-Pérot thin films, for label-free monitoring of heavy metal ions in aqueous solutions by enzymatic activity inhibition, is described. First, we show a general detection assay by immobilizing horseradish peroxidase (HRP) within the oxidized PSi nanostructure and monitor its catalytic activity in real time by reflective interferometric Fourier transform spectroscopy. Optical studies reveal the high specificity and sensitivity of the HRP-immobilized PSi towards three metal ions (Ag(+) > Pb(2+) > Cu(2+)), with a detection limit range of 60-120 ppb. Next, we demonstrate the concept of specific detection of Cu(2+) ions (as a model heavy metal) by immobilizing Laccase, a multi-copper oxidase, within the oxidized PSi. The resulting biosensor allows for specific detection and quantification of copper ions in real water samples by monitoring the Laccase relative activity. The optical biosensing results are found to be in excellent agreement with those obtained by the gold standard analytical technique (ICP-AES) for all water samples. The main advantage of the presented biosensing concept is the ability to detect heavy metal ions at environmentally relevant concentrations using a simple and portable experimental setup, while the specific biosensor design can be tailored by varying the enzyme type.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Veda Prakash, G.; Kumar, R.; Saurabh, K.
A comparative study of electrical breakdown properties of deionized water (H{sub 2}O) and heavy water (D{sub 2}O) 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 ofmore » 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.« less
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Li, Jing; Yu, Haixin; Luan, Yaning
2015-01-01
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. PMID:26703632
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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.
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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.
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Measurement of 14C emission rates from a pressurised heavy water reactor.
Joshi, M L; Ramamirtham, B; Soman, S D
1987-06-01
Carbon-14 is produced in pressurised heavy water reactors (PHWR), mainly as an activation product in the fuel. It is also produced in the heavy water used as the primary coolant and moderator, and is produced in the air in the annular space between the pressure tube and calandria tubes as well as in the free space in the calandria vault. The production rates in different systems of a PHWR are calculated on the basis of design parameters. During a period of 3 y, 14C released through the gaseous route has been measured at Rajasthan Atomic Power Station, Kota, India, a PHWR unit. These releases have been found to be mainly 14CO2. This reduced form of 14C is less than 5% of the releases. The normalised releases of 14C have a geometric mean of 5.17 TBq GWe-1 y-1 and a geometric standard deviation of 1.52. The 14C present in the form of carbonates in liquid effluents has also been measured and is 0.14% of the gaseous releases.
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NASA Astrophysics Data System (ADS)
Showqi, Irfana; Lone, Farooq Ahmad; Naikoo, Mehrajuddin
2018-06-01
Water samples, sediments and free floating macrophytic plant, Lemna minor specimens were collected from five designated sites in Anchar lake (Srinagar, J&K, India) to assess its heavy metal (Cu, Cr, Zn, Ni, Cd, Pb) load and changes on seasonal basis. The concentration of heavy metals was determined using atomic absorption spectroscopy. Most of the samples were found within limits of maximum permissible concentrations as recommended by WHO (Guidelines for drinking water quality, pp 491-493, 2006). During all the seasons, highest concentration of all heavy metals (Cu, Cr, Zn, Ni, Cd, Pb) was recorded at highly polluted sites of the lake viz. near agricultural fields (S1), near settlements (S3) and SKIMS (S4). These sites received huge agrochemical run-off from the surrounding agricultural fields, solid and liquid wastes from the nearby catchment areas and effluents from Sher-e-Kashmir Institute of Medical Sciences (SKIMS) compared to control site lake centre (S5). Furthermore, most of the metals in water and sediment were found with highest concentration during autumn (Viz., Cu-1.5 ppm; Zn-0.38 ppm; Ni-1.89 ppm; Pb-0.84 ppm in water and Cu-26.9 ppm; Zn-13.6 ppm; Pb-4.33 ppm in sediment) and summer (Viz., Cr-0.68 ppm in water and Ni-4.8 ppm; Cd-2.6 ppm; Cr-8.01 ppm in sediment) seasons. Also in Lemna minor plant highest concentration was observed during summer season (Cu-29.09 ppm; Zn-19.11 ppm; Ni-5.7 ppm; Cd-1.34 ppm; Cr-9.18 ppm and Pb-9.77 ppm). From these observations, it was found that the sources of heavy metals in Anchar lake were both natural and anthropogenic ones. This study recommended that continuous monitoring of heavy metals (Viz; Cu, Cr, Zn, Ni, Cd and Pb) in water, sediment and other aquatic biota of Anchar lake should be directed to protection of ecological status of the lake and its surrounding area.
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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.
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Liu, Jie; Zhang, Xue-Hong; Tran, Henry; Wang, Dun-Qiu; Zhu, Yi-Nian
2011-11-01
The objective of this paper is to assess the impact of long-term electroplating industrial activities on heavy metal contamination in agricultural soils and potential health risks for local residents. Water, soil, and rice samples were collected from sites upstream (control) and downstream of the electroplating wastewater outlet. The concentrations of heavy metals were determined by an atomic absorption spectrophotometer. Fractionation and risk assessment code (RAC) were used to evaluate the environmental risks of heavy metals in soils. The health risk index (HRI) and hazard index (HI) were calculated to assess potential health risks to local populations through rice consumption. Hazardous levels of Cu, Cr, and Ni were observed in water and paddy soils at sites near the plant. According to the RAC analysis, the soils showed a high risk for Ni and a medium risk for Cu and Cr at certain sites. The rice samples were primarily contaminated with Ni, followed by Cr and Cu. HRI values >1 were not found for any heavy metal. However, HI values for adults and children were 2.075 and 1.808, respectively. Water, paddy soil, and rice from the studied area have been contaminated by Cu, Cr, and Ni. The contamination of these elements is related to the electroplating wastewater. Although no single metal poses health risks for local residents through rice consumption, the combination of several metals may threaten the health of local residents. Cu and Ni are the key components contributing to the potential health risks.
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IMMOBILIZATION OF HEAVY METALS IN SOILS AND WATER BY A MANGANESE MINERAL
A synthesized Mn mineral used in study on adsorption of heavy metals from water has shown a great adsorption capability for Pb, Cu, Cd, Co, Ni and Zn on this mineral over a pH range from 2 to 8. The retention of Pb on this mineral was as high as 10% of its weight. Application of ...
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Heavy metal removal from waste waters by ion flotation.
Polat, H; Erdogan, D
2007-09-05
Flotation studies were carried out to investigate the removal of heavy metals such as copper (II), zinc (II), chromium (III) and silver (I) from waste waters. Various parameters such as pH, collector and frother concentrations and airflow rate were tested to determine the optimum flotation conditions. Sodium dodecyl sulfate and hexadecyltrimethyl ammonium bromide were used as collectors. Ethanol and methyl isobutyl carbinol (MIBC) were used as frothers. Metal removal reached about 74% under optimum conditions at low pH. At basic pH it became as high as 90%, probably due to the contribution from the flotation of metal precipitates.
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Heavy and extra heavy hydrocarbons in Venezuela
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zamora, L.G.; Gallango, O.E.
1993-02-01
Most of Venezuela's giant accumulations of heavier thatn 22[degrees] API hydrocarbons, are located in the more stable flanks of the Maracaibo and Eastern Venezuela basins, at depths shallower than 2400 meters. The reservoir rocks are unconsolidated fluviodeltaic Neogene sands, transgressive over large regional Oligocene unconformities. There are also large volumes accumulated along the mountainous and more active flanks, either in Neogene alluvial sediments or in Cretaceous and older fractured rocks. These accumulations, located near present day erosion surfaces, are subjected to meteoric water influx. Extensive research carried out by the affiliates of Petroleos de Venezuela, S.A., and other institutions duringmore » the past ten years, has shown tha the main cause of degradation is the action of microorganisms brought in by meteoric water influx and, to less extent, the washing of lighter hydrocarbon fractions by either connate or meteric water. These studies have also shown that most of the heavy and extra-heavy hydrocarbons are the result of biodegradation of low maturity crudes generated from Cretaceous rocks, rich in marine organic matter, which started its generation during the Paleogene. The heavy and extra-heavy hydrocarbons, bitumen included, so far discovered in Venezuela, add up to 1.5 [times] 10[sup 12] bbl in place. This figure includes proved, probable and possible volumes, and the expectancy of additional hydrocarbons of this kind to be discovered yet is of 0.1 [times] 10[sup 12] bbl in place.« less
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Modeling Adsorption Based Filters (Bio-remediation of Heavy Metal Contaminated Water)
NASA Astrophysics Data System (ADS)
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.
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Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey
Aydin, Mehmet Emin; Ozcan, Senar; Beduk, Fatma; Tor, Ali
2013-01-01
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. PMID:23533363
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Das, Suchismita; Choudhury, Shamim Sultana
2016-01-01
The aim of this study was to assess the regional impacts of heavy metals (Mn, Fe, Mg, Ca, Cu, Zn, Cd, Cr, Pb and Ni) on water, sediment and a native, teleost fish species, Labeo angra, inhabiting a flood plain wetland of Barak River in Assam, India. Heavy metal concentrations in the water, sediments and fish were measured; bioaccumulation factor, metal pollution index as well as condition indices were calculated, to assess the pollution load and health status of the fish. Multivariate statistical analysis was used on wetland water and sediment heavy metals to ascertain the possible sources and seasonal variations of the pollutants. Results showed that most heavy metals in the wetland water and sediments exceeded the water (drinking and irrigation) and sediment quality guidelines, respectively. Seasonal variations were observed for geogenic heavy metals, Mn, Fe, Mg and Ca while no seasonal variations were observed for anthropogenic heavy metals, Cu, Cd, Cr, Pb and Ni. Multivariate statistical analysis showed that there was strong correlation between geogenic and anthropogenic heavy metals in water and sediment, both originating from the common anthropogenic sources. Accumulation of most of the metals in all the tissues was above the safe limits as recommended by the Food and Agriculture Organization. High bioaccumulation factors and metal pollution index for these metals in the different tissues revealed that metals were extensively bio-accumulated and bioconcentrated. Condition indices in fish from the wetland suggested metabolic abnormalities.
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Njuguna, Samwel Maina; Yan, Xue; Gituru, Robert Wahiti; Wang, Qingfeng; Wang, Jun
2017-08-16
Nairobi River tributaries are the main source of the Athi River. The Athi River basin is the fourth largest and important drainage system in Kenya covering 650 km and with a drainage area of 70,000 km 2 . Its water is used downstream by about four million people not only for irrigation but also for domestic purposes. However, its industrial, raw sewer, and agricultural pollution is alarming. In order to understand distribution and concentration of heavy metals and nutrients in the water of Nairobi River, 28 water samples were collected in the rainy season (October) of 2015 and dry season (June) of 2016. Cd, Cu, Cr, Zn, As, Pb, Fe, Ni, Mn, NO 3 - , and TP were analyzed. Only Cr, Pb, Fe, and Mn had concentrations exceeding the WHO permissible limit for drinking water. Out of the 28 sites examined in the study, one site had Pb exceeding the WHO recommended level. Similarly, three sites exceeded the same level for Cr. Only three sites were within the WHO permissible limits for drinking water for Mn while just four sites were within USEPA limit for Fe. Industrial effluent, domestic sewerage, agricultural activities, and solid waste were the main sources of pollution. Significant spatial variation of both heavy metals and nutrients concentration was observed and emanated from point source pollution. Eleven out of 31 macrophytes species that were identified along the river and its tributaries are effective heavy metal and nutrient bioaccumulators and may be used in phytoremediation.
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Competitive sorption of heavy metals by water hyacinth roots.
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.
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ERIC Educational Resources Information Center
Labov, Jay B.
2005-01-01
This column, "From the National Academies," was Bruce Alberts' idea, one of so many for improving education. As a long-standing member of the American Society for Cell Biology, the namesake for the prize that is awarded annually to cell biologists for excellence in science education, and one of the founding editors of this journal, Alberts…
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Pelletized ponderosa pine bark for adsorption of toxic heavy metals from water
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...
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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.
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Seid-Mohammadi, Abdolmotaleb; Roshanaei, Ghodratollah; Asgari, Ghorban
2014-01-01
This study was conducted to estimate the level of heavy metals accumulate in vegetables irrigated with contaminated water compared with those irrigated with fresh water in Hamadan, west of Iran in 2012. Sixty samples of different vegetables i.e., parsley, tarragon, sweat basil and leek irrigated with contaminated water and thirty six samples from three different adjacent areas irrigated with fresh water as control were analyzed to determine heavy metals. The concentration of heavy metals i.e., lead, cadmium and chromium were achieved using atomic adsorption spectrophotometer. The mean concentration of lead, chromium and cadmium regardless of the kind of vegetables irrigated with contaminated water was 6.24, 1.57 and 0.15 mg/kg, respectively. Moreover, metals uptake differences by the vegetables were recognized to vegetable differences in tolerance to heavy metals. Based on the above concentrations the dietary intakes of metals through vegetables consumption were 0.004, 0.0008 and 6E-05 mg/day in infants for lead, chromium and cadmium, respectively. The high concentration of these heavy metals in some vegetables might be attributed due to the use of untreated sanitary and industrial wastewater by farmers for the irrigation of vegetable lands. Therefore, treating of these wastewater and bioremediation of excess metals from polluted vegetation land could be considered.
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ERIC Educational Resources Information Center
Davidson, Judith
2014-01-01
Bruce and Bishop's community informatics work brings forward four critical concepts: inquiry, community, technology, and literacy. These four terms serve as the basis for a discussion of qualitative research in the twenty-first century--what is lacking and what is needed. The author suggests that to resolve the tensions or challenges…
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Armah, Frederick A; Obiri, Samuel; Yawson, David O; Onumah, Edward E; Yengoh, Genesis T; Afrifa, Ernest K A; Odoi, Justice O
2010-11-01
The levels of heavy metals in surface water and their potential origin (natural and anthropogenic) were respectively determined and analysed for the Obuasi mining area in Ghana. Using Hawth's tool an extension in ArcGIS 9.2 software, a total of 48 water sample points in Obuasi and its environs were randomly selected for study. The magnitude of As, Cu, Mn, Fe, Pb, Hg, Zn and Cd in surface water from the sampling sites were measured by flame Atomic Absorption Spectrophotometry (AAS). Water quality parameters including conductivity, pH, total dissolved solids and turbidity were also evaluated. Principal component analysis and cluster analysis, coupled with correlation coefficient analysis, were used to identify possible sources of these heavy metals. Pearson correlation coefficients among total metal concentrations and selected water properties showed a number of strong associations. The results indicate that apart from tap water, surface water in Obuasi has elevated heavy metal concentrations, especially Hg, Pb, As, Cu and Cd, which are above the Ghana Environmental Protection Agency (GEPA) and World Health Organisation (WHO) permissible levels; clearly demonstrating anthropogenic impact. The mean heavy metal concentrations in surface water divided by the corresponding background values of surface water in Obuasi decrease in the order of Cd > Cu > As > Pb > Hg > Zn > Mn > Fe. The results also showed that Cu, Mn, Cd and Fe are largely responsible for the variations in the data, explaining 72% of total variance; while Pb, As and Hg explain only 18.7% of total variance. Three main sources of these heavy metals were identified. As originates from nature (oxidation of sulphide minerals particularly arsenopyrite-FeAsS). Pb derives from water carrying drainage from towns and mine machinery maintenance yards. Cd, Zn, Fe and Mn mainly emanate from industry sources. Hg mainly originates from artisanal small-scale mining. It cannot be said that the difference in concentration
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Xu, Shan-Nan; Li, Chun-Hou; Xu, Jiao-Jiao; Xiao, Ya-Yuan; Lin, Lin; Huang, Xiao-Ping
2014-06-01
This study aimed to gain a clear understanding on the status of pollution by heavy metals in the petrochemical sewage and the potential ecological risk caused by heavy metal pollution in the sea area of Daya Bay. The contents and spatial distributions of heavy metals including Zn, Pb, Cu, Cd, Cr, As and Hg in seawater, sediment and fishes collected from Daya Bay were analyzed. The comprehensive pollution index (CPI) and ecological risk indexes (ERIs) were used to evaluate the contaminated severity and potential ecological risks of heavy metals in seawater and sediment. The results showed that the contents of these heavy metals, except for those of Zn and Pb, in several stations set in Daya Bay from 2011 to 2012 were relatively low, which were lower than the quality standard of class I according to the China National Standard Criteria for Seawater Quality, suggesting that the seawater in Daya Bay has not been polluted yet by these heavy metals. The average CPI of heavy metals in seawater during flooding season (0.72) was higher than that during dry season (0.38) whereas the average CPI of heavy metals in sediment during dry season (7.77) was higher than that during flooding season (5.70). Hg was found to be the primary contaminating heavy metal in sediment during dry season, which was followed by As and Zn whereas during flooding season, Hg was the primary contaminating metal in sediment, followed by Zn and Cu. The contents of these 7 heavy metals in fishes collected from the surveyed areas were lower than those of the standard requirements. A correlation analysis indicated that there were significant differences in the correlations between the midst of the heavy metals in sea water and the different periods. The ERIs of heavy metals in sediment during dry season (129.20) was higher than that during flooding season (102.86), and 25% of the sampling sites among all stations were under the risk of high-level alarm. The potential ERIs of heavy metals in sediment in
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Heavy Metals in Water Percolating Through Soil Fertilized with Biodegradable Waste Materials.
Wierzbowska, Jadwiga; Sienkiewicz, Stanisław; Krzebietke, Sławomir; Bowszys, Teresa
The influence of manure and composts on the leaching of heavy metals from soil was evaluated in a model lysimeter experiment under controlled conditions. Soil samples were collected from experimental fields, from 0- to 90-cm layers retaining the layout of the soil profile layers, after the second crop rotation cycle with the following plant species: potatoes, spring barley, winter rapeseed, and winter wheat. During the field experiment, 20 t DM/ha of manure, municipal sewage sludge composted with straw (SSCS), composted sewage sludge (SSC), dried granular sewage sludge (DGSS), "Dano" compost made from non-segregated municipal waste (CMMW), and compost made from municipal green waste (CUGW) was applied, i.e., 10 t DM/ha per crop rotation cycle. The concentrations (μg/dm 3 ) of heavy metals in the leachate were as follows: Cd (3.6-11.5) < Mn (4.8-15.4) < Cu (13.4-35.5) < Zn (27.5-48.0) < Cr (36.7-96.5) < Ni (24.4-165.8) < Pb (113.8-187.7). Soil fertilization with organic waste materials did not contaminate the percolating water with manganese or zinc, whereas the concentrations of the other metals increased to the levels characteristic of unsatisfactory water quality and poor water quality classes. The copper and nickel content of percolating water depended on the concentration of those metals introduced into the soil with organic waste materials. The concentrations of Cd in the leachate increased, whereas the concentrations of Cu and Ni decreased with increasing organic C content of organic fertilizers. The widening of the C/N ratio contributed to Mn leaching. The concentrations of Pb, Cr, and Mn in the percolating water were positively correlated with the organic C content of soil.
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ERIC Educational Resources Information Center
Johnson, Cynthia
2017-01-01
In 2012, Bruce Horner guest edited a special issue of "JAC" focused on "Economies of Writing" ("JAC" n3-4 p453-778 2012). In his introduction, he explains that the included essays originated from an October 2011 symposium at the University of Louisville, held in preparation for the similarly-themed 2012 Thomas R.…
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Qi, Peng; Yu, Shu-quan; Zhang, Chao; Liang, Li-cheng; Che, Ji-lu
2015-12-01
In order to understand the pollution characteristics of heavy metals in surface water sediments of Yongkang, we analyzed the concentrations of 10 heavy metals including Ti, Cr, Mn, Co, Ni, Cu, Zn, As, Pb and Fe in 122 sediment samples, explored the underlying source of heavy metals and then assessed the potential ecological risks of those metals by methods of the index of geo-accumulation and the potential ecological risk. The study results showed that: 10 heavy metal contents followed the order: Fe > Ti > Mn > Zn > Cr > Cu > Ph > Ni > As > Co, all heavy metals except for Ti were 1. 17 to 3.78 times higher than those of Zhejiang Jinhua- Quzhou basin natural soils background values; The concentrations of all heavy metals had a significantly correlation between each other, indicating that those heavy metals had similar sources of pollution, and it mainly came from industrial and vehicle pollutions; The pollution extent of heavy metals in sediments by geo-accumulation index (Igeo) followed the order: Cr > Zn > Ni > Cu > Fe > As > Pb >Mn > Ti, thereinto, Cr, Zn, Cu and Ni were moderately polluted or heavily polluted at some sampling sites; The potential ecological risk of 9 heavy metals in sediments were in the following order: Cu > As > Ni > Cr > Pb > Co > Zn > Mn > Ti, Cu and As contributed the most to the total potential ecological risk, accounting for 22.84% and 21. 62% , others had a total of 55.54% , through the ecological risk assessment, 89. 34% of the potential ecological risk indexes ( RI) were low and 10. 66% were higher. The contamination level of heavy metals in Yongkang was slight in total, but was heavy in local areas.
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Tekin-Ozan, Selda
2008-10-01
In the present study, some heavy metals (Cu, Fe, Zn and Mn) were seasonally determined in water, sediment and some tissues of fish Tinca tinca from Beyşehir Lake, which is an important bird nesting and visiting area, a water source for irrigation and drinking. In the water, Fe has the highest concentrations among the studied metals. Generally, the metal concentrations increased in the hottest period decreased in warm seasons. Results for levels in water were compared with national and international water quality guidelines, as well as literature data reported for the lakes. Fe was the highest in sediment samples, also Cu and Zn were the highest in spring, while Fe and Mn were in autumn. Among the heavy metals studied, Cu and Mn were below the detection limits in some tissues. Generally, higher concentrations of the tested metals were found in the summer and winter, compared with those during the autumn and spring seasons. High levels of heavy metals were found in liver of T. tinca, while low levels in muscle samples. Metal concentrations in the muscle of examined fish were within the safety permissible levels for human consumption. The present study shows that precautions need to be taken in order to prevent further heavy metal pollution.
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Ecotoxic heavy metals transformation by bacteria and fungi in aquatic ecosystem.
Chaturvedi, Amiy Dutt; Pal, Dharm; Penta, Santhosh; Kumar, Awanish
2015-10-01
Water is the most important and vital molecule of our planet and covers 75% of earth surface. But it is getting polluted due to high industrial growth. The heavy metals produced by industrial activities are recurrently added to it and considered as dangerous pollutants. Increasing concentration of toxic heavy metals (Pb(2+), Cd(2+), Hg(2+), Ni(2+)) in water is a severe threat for human. Heavy metal contaminated water is highly carcinogenic and poisonous at even relatively low concentrations. When they discharged in water bodies, they dissolve in the water and are distributed in the food chain. Bacteria and fungi are efficient microbes that frequently transform heavy metals and remove toxicity. The application of bacteria and fungi may offer cost benefit in water treatment plants for heavy metal transformation and directly related to public health and environmental safety issues. The heavy metals transformation rate in water is also dependent on the enzymatic capability of microorganisms. By transforming toxic heavy metals microbes sustain aquatic and terrestrial life. Therefore the application of microbiological biomass for heavy metal transformation and removal from aquatic ecosystem is highly significant and striking. This paper reviews the microbial transformation of heavy metal, microbe metal interaction and different approaches for microbial heavy metal remediation from water bodies.
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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.
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Method and apparatus for separation of heavy and tritiated water
Lee, Myung W.
2001-01-01
The present invention is a bi-thermal membrane process for separating and recovering hydrogen isotopes from a fluid containing hydrogen isotopes, such as water and hydrogen gas. The process in accordance with the present invention provides counter-current cold and hot streams of the fluid separated with a thermally insulating and chemically transparent proton exchange membrane (PEM). The two streams exchange hydrogen isotopes through the membrane: the heavier isotopes migrate into the cold stream, while the lighter isotopes migrate into the hot stream. The heavy and light isotopes are continuously withdrawn from the cold and hot streams respectively.
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NASA Astrophysics Data System (ADS)
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.
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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 (p<0.05) decreased with a change of irrigation water sources compared to Tangjun, without change of irrigation water source. Similarly, the Cd (39.1-81.3%) and Hg (60.0-75.0%) concentrations in rice grown at Sanhe and Lasha significantly (p<0.05) decreased compared to those at Tangjun. Consequently, replacing irrigation water source significantly (p<0.05) reduced the hazard quotient (HQ) and cancer risk for the corresponding single metal via soil 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.
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The time resolved SBS and SRS research in heavy water and its application in CARS
NASA Astrophysics Data System (ADS)
Liu, Jinbo; Gai, Baodong; Yuan, Hong; Sun, Jianfeng; Zhou, Xin; Liu, Di; Xia, Xusheng; Wang, Pengyuan; Hu, Shu; Chen, Ying; Guo, Jingwei; Jin, Yuqi; Sang, Fengting
2018-05-01
We present the time-resolved character of stimulated Brillouin scattering (SBS) and backward stimulated Raman scattering (BSRS) in heavy water and its application in Coherent Anti-Stokes Raman Scattering (CARS) technique. A nanosecond laser from a frequency-doubled Nd: YAG laser is introduced into a heavy water cell, to generate SBS and BSRS beams. The SBS and BSRS beams are collinear, and their time resolved characters are studied by a streak camera, experiment show that they are ideal source for an alignment-free CARS system, and the time resolved property of SBS and BSRS beams could affect the CARS efficiency significantly. By inserting a Dye cuvette to the collinear beams, the time-overlapping of SBS and BSRS could be improved, and finally the CARS efficiency is increased, even though the SBS energy is decreased. Possible methods to improve the efficiency of this CARS system are discussed too.
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Dutta, Joydev; Chetia, Mridul; Misra, A K
2011-10-01
Contamination of drinking water by arsenic and other heavy metals and their related toxicology is a serious concern now-a-days. Millions of individual world-wide are suffering from the arsenic and other heavy metal related diseases due to the consumption of contaminated groundwater. 60 water samples from different sources of 6 small tea gardens of Sonitpur district were collected to study the potability of water for drinking purposes. The water samples collected from sources like tube wells, ring wells and ponds were analyzed for arsenic, heavy metals like iron, manganese and mercury with sodium, potassium, calcium, magnesium, pH, total hardness, chloride, fluoride and sulphate. Some drain water samples of the tea garden areas were also collected to analyze the above mentioned water parameters to see the contamination level. Experiments revealed that 78% samples of total collection had arsenic content above the permissible limit (0.01 ppm) of WHO guideline value for drinking water. The highest arsenic was observed 0.09 ppm at one sample of Gobindra Dahal tea garden of Gohpur sub division of Sonitpur district. 94% samples had contamination due to manganese 39% samples had iron and 44% samples had Hg. The water quality data was subjected to some statistical treatments like NDA, cluster analysis and pearson correlation to observe the distribution pattern of the different water quality parameters. A strong pearson correlation coefficient was observed between parameters-arsenic and manganese (0.865) and arsenic and mercury (0.837) at 0.01 level, indicated the same sources of drinking water contamination.
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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.
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Verma, Roli; Gupta, Banshi D
2015-01-01
Optical fibre surface plasmon resonance (SPR) based sensor for the detection of heavy metal ions in the drinking water is designed. Silver (Ag) metal and indium tin oxide (ITO) are used for the fabrication of the SPR probe which is further modified with the coating of pyrrole and chitosan composite. The sensor works on the wavelength interrogation technique and is capable of detecting trace amounts of Cd(2+), Pb(2+), and Hg(2+) heavy metal ions in contaminated water. Four types of sensing probes are fabricated and characterised for heavy metal ions out of these pyrrole/chitosan/ITO/Ag coated probe is found to be highly sensitive among all other probes. Further, the cadmium ions bind strongly to the sensing surface than other ions and due to this the sensor is highly sensitive for Cd(2+) ions. The sensor's performance is best for the low concentrations of heavy metal ions and its sensitivity decreases with the increasing concentration of heavy metal ions. Copyright © 2014 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Peng, Chi; Cai, Yimin; Wang, Tieyu; Xiao, Rongbo; Chen, Weiping
2016-11-01
In this study, we proposed a Regional Probabilistic Risk Assessment (RPRA) to estimate the health risks of exposing residents to heavy metals in different environmental media and land uses. The mean and ranges of heavy metal concentrations were measured in water, sediments, soil profiles and surface soils under four land uses along the Shunde Waterway, a drinking water supply area in China. Hazard quotients (HQs) were estimated for various exposure routes and heavy metal species. Riverbank vegetable plots and private vegetable plots had 95th percentiles of total HQs greater than 3 and 1, respectively, indicating high risks of cultivation on the flooded riverbank. Vegetable uptake and leaching to groundwater were the two transfer routes of soil metals causing high health risks. Exposure risks during outdoor recreation, farming and swimming along the Shunde Waterway are theoretically safe. Arsenic and cadmium were identified as the priority pollutants that contribute the most risk among the heavy metals. Sensitivity analysis showed that the exposure route, variations in exposure parameters, mobility of heavy metals in soil, and metal concentrations all influenced the risk estimates.
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Embedded optical fibers for PDV measurements in shock-loaded, light and heavy water
NASA Astrophysics Data System (ADS)
Mercier, Patrick; Benier, Jacky; Frugier, Pierre-Antoine; Debruyne, Michel; Bolis, Cyril
2011-06-01
In order to study the shock-detonation transition, it is necessary to characterize the shock loading of a high explosive plane wave generator into a nitromethane cell. To eliminate the reactive behaviour, we replace the nitromethane by an inert liquid compound. Light water has been first employed; eventually heavy water has been chosen for its better infrared spectral properties. We present the PDV results of different submerged embedded optical fibers which sense the medium with two different approaches: a non-intrusive optical observation of phenomena coming in front of them (interface, shock wave) followed by the mechanical interaction with the shock wave.
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Measurement of /sup 14/C emission rates from a pressurized heavy water reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joshi, M.L.; Ramamirtham, B.; Soman, S.D.
Carbon-14 is produced in pressurized heavy water reactors (PHWR), mainly as an activation product in the fuel. It is also produced in the heavy water used as the primary coolant and moderator, and is produced in the air in the annular space between the pressure tube and calandria tubes as well as in the free space in the calandria vault. The production rates in different systems of a PHWR are calculated on the basis of design parameters. During a period of 3 y, /sup 14/C released through the gaseous route has been measured at Rajasthan Atomic Power Station, Kota, India,more » a PHWR unit. These releases have been found to be mainly /sup 14/CO/sub 2/. This reduced form of /sup 14/C is less than 5% of the releases. The normalized releases of /sup 14/C have a geometric mean of 5.17 TBq GWe-1 y-1 and a geometric standard deviation of 1.52. The /sup 14/C present in the form of carbonates in liquid effluents has also been measured and is 0.14% of the gaseous releases.« less
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[Research advances in heavy metals pollution ecology of diatom].
Ding, Teng-Da; Ni, Wan-Min; Zhang, Jian-Ying
2012-03-01
Diatom, due to its high sensitivity to environmental change, is one of the bio-indicators of aquatic ecosystem health, and some typical diatom species have been applied to indicate the heavy metals pollution of water body. With the focus on the surface water heavy metals pollution, this paper reviewed the research advances in the toxic effect of heavy metals pollution on diatom, biosorption and bioaccumulation of heavy metals by diatom, ecological adaptation mechanisms of diatom to heavy metals pollution, and roles of diatom as bio-indicator and in ecological restoration of heavy metals pollution. The growth tendency of diatom and the morphological change of frustule under heavy metals pollution as well as the differences in heavy metals biosorption and bioaccumulation by diatom, the ecological adaptation mechanisms of diatom on heavy metals surface complexation and ion exchange, and the roles of diatom as bio-indicator and in ecological restoration of heavy metals polluted water body were also discussed. This review could provide scientific evidences for the prevention of aquatic ecosystems heavy metals pollution and related early warning techniques.
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NASA Astrophysics Data System (ADS)
Ding, Wenhua; Li, Shaopo; Li, Jiading; Li, Qun; Chen, Tieqiang; Zhang, Hai
In recent years, there has been development of several significant pipeline projects for the transmission of oil and gas from deep water environments. The production of gas transmission pipelines for application demands heavy wall, high strength, good lower temperature toughness and good weldability. To overcome the difficulty of producing consistent mechanical property in heavy wall pipe Shougang Steel Research in cooperation with the Shougang Steel Qinhuangdao China (Shouqin) 4.3m heavy wide plate mill research was conducted.
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Plant water relations as affected by heavy metal stress: A review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barcelo, J.; Poschenrieder, C.
1990-01-01
Metal toxicity causes multiple direct and indirect effects in plants which concern practically all physiological functions. In this review the effects of excess heavy metals and aluminum on those functions which will alter plant water relations are considered. After a brief comment on the metal effects in cell walls and plasma-lemma, and their consequences for cell expansion growth, the influences of high meal availability on the factors which regulate water entry and water exit in plants are considered. Emphasis is placed on the importance of distinguishing between low water availability in mine and serpentine soils and toxicity effects in plantsmore » which may impair the ability of a plant to regulate water uptake. Examples on water relations of both plants grown on metalliferous soil and hydroponics are presented, and the effects of metal toxicity on root growth, water transport and transpiration are considered. It is concluded that future research has to focus on the mechanisms of metal-induced inhibition of both root elongation and morphogenetic processes within roots. In order to understand the relation between metal tolerance and drought resistance better, further studies into metal tolerance mechanisms at the cell wall, membrane and vacuolar level, as well as into the mechanisms of drought resistance of plants adapted to metalliferous soils are required. 135 refs., 7 figs., 6 tabs.« less
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Bhuiyan, Mohammad Amir Hossain; Dampare, Samuel B; Islam, M A; Suzuki, Shigeyuki
2015-01-01
Concentrations of heavy metals in water and sediment samples of Buriganga River in the capital city Dhaka, Bangladesh, were studied to understand the level of heavy metals and their source apportionment. The results showed that the mean concentrations of heavy metals both in water and sediment samples were very high and, in most cases, exceeded the permissible limits recommended by the Bangladesh government and other international organizations. Significantly higher concentrations of Pb, Cr, Mn, Co, Ni, Cu, Zn, As, and Cd were found in sediment samples. However, average concentrations of metals both in water and sediment samples were above the effect range median. The heavy metal pollution index (HPI) and degree of contamination (Cd) yielded different results in water samples despite significant correlations between them. The heavy metal evaluation index (HEI) showed strong correlations with HPI and Cd and provided better assessment of pollution levels. The enrichment factor (EF) and geoaccumulation index (Igeo) showed the elevated value of Cr, Pb, and Cd in access of background values. The measured elements were subjected to positive matrix factorization (PMF) and examining correlations in order to explain the content, behavior, and source apportionment of metals. PMF resulted in a successful partitioning of variances into sources related to background geochemistry and contaminant influences. However, the PMF approach successfully demarcated the major sources of metals from tannery, paint, municipal sewage, textiles, and agricultural activities.
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Removal of heavy metals from waste streams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spence, M.D.; Kozaruk, J.M.; Melvin, M.
1988-07-19
A method for removing heavy metals from effluent water is described comprising performing sequentially the following steps: (a) adding from 7-333 ppm of an anionic surfactant to the effluent water to provide coagulatable heavy metal ion; (b) adjusting the effluent water pH to within the range of 8 to 10, (c) providing from 10-200 ppm of a cationic coagulant to coagulate the heavy metal ion, (d) providing from 0.3 to 5.0 ppm of a polymeric flocculant whereby a heavy metal containing floc is formed for removal from the effluent water, and, (e) then removing the floc from the effluent water,more » wherein the anionic surfactant is sodium lauryl ether sulfate. The cationic coagulant is selected from the group consisting of diallyl dimethylammonium chloride polymer, epichlorohydrin dimethylamine polymer, ethylene amine polymer, polyaluminum chloride, and alum; and the flocculant is an acrylamide/sodium acrylate copolymer having an RSV greater than 23.« less
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Generation of Hot Water from Hot-Dry for Heavy-Oil Recovery in Northern Alberta, Canada
NASA Astrophysics Data System (ADS)
Pathak, V.; Babadagli, T.; Majorowicz, J. A.; Unsworth, M. J.
2011-12-01
The focus of prior applications of hot-dry-rock (HDR) technology was mostly aimed at generating electricity. In northern Alberta, the thermal gradient is low and, therefore, this technology is not suitable for electricity generation. On the other hand, the cost of steam and hot water, and environmental impacts, are becoming critical issues in heavy-oil and bitumen recovery in Alberta. Surface generation of steam or hot-water accounts for six percent of Canada's natural gas consumption and about 50 million tons of CO2 emission. Lowered cost and environmental impacts are critical in the widespread use of steam (for in-situ recovery) and hot-water (for surface extraction of bitumen) in this region. This paper provides an extensive analysis of hot-water generation to be used in heavy-oil/bitumen recovery. We tested different modeling approaches used to determine the amount of energy produced during HDR by history matching to example field data. The most suitable numerical and analytical models were used to apply the data obtained from different regions containing heavy-oil/bitumen deposits in northern Alberta. The heat generation capacity of different regions was determined and the use of this energy (in the form of hot-water) for surface extraction processes was evaluated. Original temperature gradients were applied as well as realistic basement formation characteristics through an extensive hydro thermal analysis in the region including an experimental well drilled to the depth of 2,500m. Existing natural fractures and possible hydraulic fracturing scenarios were evaluated from the heat generation capacity and the economics points of view. The main problem was modeling difficulties, especially determination and representation of fracture network characteristics. A sensitivity analysis was performed for the selected high temperature gradient regions in Alberta. In this practice, the characteristics of hydraulic fractures, injection rate, depth, the distance between
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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.
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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.
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Heavy metal hazards of sachet water in Nigeria.
Orisakwe, Orish Ebere; Igwilo, Innocent O; Afonne, Onyenmechi Johnson; Maduabuchi, John-Moses Ugwuona; Obi, Ejeatuluchukwu; Nduka, John C
2006-01-01
The authors assessed sachet water samples sold in Eastern Nigeria. Using an atomic absorption spectrophotometer, they analyzed levels of lead, cadmium, copper, and nickel. They also analyzed other parameters, such as nitrates, sulfates, chlorides, salinity, total hardness, biological oxygen demand, total dissolved solids, and pH level. Lead levels ranged from 0.002 to 0.036 mg/L in the samples; 5 samples (12.2%) had lead levels above the maximum contaminant level (MCL; 0.015 mg/L). Lead was not detectable in 20 samples (48.8%). Cadmium levels ranged from 0.002 to 0.036 mg/L and exceeded the MCL of 0.005 mg/L in 8 samples (19.5%); it was not detectable in 23 samples (56.1%). Copper was not detected in 2 (0.05%) of the samples. Its range was between 0.018 and 1.401 mg/L. Two samples (0.05%) had copper levels above the MCL (1.30 mg/L). Nickel levels ranged from 0.003 to 0.050 mg/l. The biological oxygen demand of the samples ranged from 3.20 to 36.80 mg/L. Other parameters were normal. The authors found that some of the sachet waters contain heavy metals, and consumers may be exposed to hazards.
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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 NO 3 - were higher during summer and Br - and SO 4 - were higher during spring. Our research findings showed anion concentration decreased in the order of Cl - > SO 4 - > NO 3 - > 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
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Hydraulic Testing of Silurian and Ordovician Strata at the Bruce Site
NASA Astrophysics Data System (ADS)
Beauheim, R. L.; Avis, J. D.; Chace, D. A.; Roberts, R. M.; Toll, N. J.
2009-05-01
Ontario Power Generation is proposing a Deep Geologic Repository (DGR) for the long-term management of its Low and Intermediate Level Radioactive Waste (L&ILW) within a Paleozoic-age sedimentary sequence beneath the Bruce Site near Tiverton, Ontario, Canada. The concept envisions that the DGR would be excavated at a depth of approximately 680 m within the Ordovician Cobourg Formation, a massive, dense, argillaceous limestone. A key attribute of the Bruce site is the extremely low permeabilities associated with the thick Ordovician carbonate and argillaceous bedrock formations that will host and enclose the DGR. Such rock mass permeabilities are thought sufficiently low to contribute toward or govern a diffusion-dominated transport regime. To support this concept, hydraulic testing was performed in 2008 and 2009 in two deep boreholes at the proposed repository site, DGR-3 and DGR-4. The hydraulic testing was performed using a straddle-packer tool with a 30.74-m test interval. Sequential tests were performed over the entire open lengths of the boreholes from the F Unit of the Silurian Salina Formation into the Ordovician Gull River Formation, a distance of approximately 635 m. The tests consisted primarily of pressure-pulse tests, with a few slug tests performed in several of the higher permeability Silurian units. The tests are analyzed using the nSIGHTS code, which allows the entire pressure history a test interval has experienced since it was penetrated by the drill bit to be included in the test simulation. nSIGHTS also allows the model fit to the test data to be optimized over an n-dimensional parameter space to ensure that the final solution represents a true global minimum rather than simply a local minimum. The test results show that the Ordovician-age strata above the Coboconk Formation (70+ m below the Cobourg) have average horizontal hydraulic conductivities of 1E-13 m/s or less. Coboconk and Gull River hydraulic conductivities are as high as 1E-11 m
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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.
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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.
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Cobbina, Samuel J.; Duwiejuah, Abudu B.; Quansah, Reginald; Obiri, Samuel; Bakobie, Noel
2015-01-01
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. PMID:26343702
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Characteristics of a heavy water photoneutron source in boron neutron capture therapy
NASA Astrophysics Data System (ADS)
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.
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Embedded optical fibers for PDV measurements in shock-loaded, light and heavy water
NASA Astrophysics Data System (ADS)
Mercier, Patrick; Benier, Jacky; Frugier, Pierre Antoine; Debruyne, Michel; Bolis, Cyril
2012-03-01
In order to study the shock-detonation transition, we propose to characterize the shock loading of a high explosive plane wave generator into a nitromethane cell. To eliminate the reactive behaviour, we replace the nitromethane by an inert liquid compound. Light water (H2O) has been first employed; eventually heavy water (D2O) has been chosen for its better infrared spectral properties. We present the PDV results of different embedded optical fibers which sense the medium with two different approaches: a non intrusive optical observation of phenomena coming in front of them (interface, shock wave, detonation wave) followed by their mechanical interaction with the fiber.
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Separation and recovery of heavy metals from waste water using synergistic solvent extraction
NASA Astrophysics Data System (ADS)
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.
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Heavy Metals in Soils and Vegetables Irrigated with Urban Grey Waste Water in Fagge, Kano, Nigeria.
Chiroma, T M; Ebewele, R O; Hymore, F K
2014-01-01
There is currently an increased consumption of vegetables within the local urban community. However, contamination of these vegetables with heavy metals poses a potential health hazard. Consequently, the potential contamination problem due to the effect of levels of some heavy metals (Fe, Mg, Zn, Mn, Cu and Cr) in soils and vegetables irrigated with drainage urban grey waste water were investigated. The maximum levels of Fe, Zn, Mn, Cu and Cr in the urban grey waste waters were respectively 2.8, 2.1, 19.5, 2.3 and 143.1 times, higher than the maximum recommended concentrations of these metals: 5.0 μg/mL, 2.0 μg/mL, 0.2 μg/mL, 0.2 μg/mL and 0.1 μg/mL, respectively, for irrigation waters. The soils were found to be contaminated with these metals to levels that range between 24 to 84 percent contaminations. Although the heavy metals concentration ranking in vegetable parts vary with plant specie, the concentrations of Fe, Zn, Mn, Cu and Cr in most parts of the vegetables were above their critical concentrations of 750 - 1000 μg/g, 100 - 400 μg/g, 300 - 500 μg/g, 20 - 100 μg/g and 5 - 30 μg/g, respectively, in plants. This suggests potential toxicity of these parts of vegetables. It was however found that over 40 percent of the concentrations of Fe, Mg, Zn and Cu in Onions, Fe in Okro, Cr in Bushgreen, Cu in Roselle and Zn, Cu in Carrot leaves can be easily removed by washing the leaves with water. However, only Cu concentration in Onions and Bushgreen leaves met the acceptable permissible level in plants after washing.
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Rapid, Selective Heavy Metal Removal from Water by a Metal-Organic Framework/Polydopamine Composite.
Sun, Daniel T; Peng, Li; Reeder, Washington S; Moosavi, Seyed Mohamad; Tiana, Davide; Britt, David K; Oveisi, Emad; Queen, Wendy L
2018-03-28
Drinking water contamination with heavy metals, particularly lead, is a persistent problem worldwide with grave public health consequences. Existing purification methods often cannot address this problem quickly and economically. Here we report a cheap, water stable metal-organic framework/polymer composite, Fe-BTC/PDA, that exhibits rapid, selective removal of large quantities of heavy metals, such as Pb 2+ and Hg 2+ , from real world water samples. In this work, Fe-BTC is treated with dopamine, which undergoes a spontaneous polymerization to polydopamine (PDA) within its pores via the Fe 3+ open metal sites. The PDA, pinned on the internal MOF surface, gains extrinsic porosity, resulting in a composite that binds up to 1634 mg of Hg 2+ and 394 mg of Pb 2+ per gram of composite and removes more than 99.8% of these ions from a 1 ppm solution, yielding drinkable levels in seconds. Further, the composite properties are well-maintained in river and seawater samples spiked with only trace amounts of lead, illustrating unprecedented selectivity. Remarkably, no significant uptake of competing metal ions is observed even when interferents, such as Na + , are present at concentrations up to 14 000 times that of Pb 2+ . The material is further shown to be resistant to fouling when tested in high concentrations of common organic interferents, like humic acid, and is fully regenerable over many cycles.
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Rapid, Selective Heavy Metal Removal from Water by a Metal–Organic Framework/Polydopamine Composite
2018-01-01
Drinking water contamination with heavy metals, particularly lead, is a persistent problem worldwide with grave public health consequences. Existing purification methods often cannot address this problem quickly and economically. Here we report a cheap, water stable metal–organic framework/polymer composite, Fe-BTC/PDA, that exhibits rapid, selective removal of large quantities of heavy metals, such as Pb2+ and Hg2+, from real world water samples. In this work, Fe-BTC is treated with dopamine, which undergoes a spontaneous polymerization to polydopamine (PDA) within its pores via the Fe3+ open metal sites. The PDA, pinned on the internal MOF surface, gains extrinsic porosity, resulting in a composite that binds up to 1634 mg of Hg2+ and 394 mg of Pb2+ per gram of composite and removes more than 99.8% of these ions from a 1 ppm solution, yielding drinkable levels in seconds. Further, the composite properties are well-maintained in river and seawater samples spiked with only trace amounts of lead, illustrating unprecedented selectivity. Remarkably, no significant uptake of competing metal ions is observed even when interferents, such as Na+, are present at concentrations up to 14 000 times that of Pb2+. The material is further shown to be resistant to fouling when tested in high concentrations of common organic interferents, like humic acid, and is fully regenerable over many cycles. PMID:29632880
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Using total precipitable water anomaly as a forecast aid for heavy precipitation events
NASA Astrophysics Data System (ADS)
VandenBoogart, Lance M.
Heavy precipitation events are of interest to weather forecasters, local government officials, and the Department of Defense. These events can cause flooding which endangers lives and property. Military concerns include decreased trafficability for military vehicles, which hinders both war- and peace-time missions. Even in data-rich areas such as the United States, it is difficult to determine when and where a heavy precipitation event will occur. The challenges are compounded in data-denied regions. The hypothesis that total precipitable water anomaly (TPWA) will be positive and increasing preceding heavy precipitation events is tested in order to establish an understanding of TPWA evolution. Results are then used to create a precipitation forecast aid. The operational, 16 km-gridded, 6-hourly TPWA product developed at the Cooperative Institute for Research in the Atmosphere (CIRA) compares a blended TPW product with a TPW climatology to give a percent of normal TPWA value. TPWA evolution is examined for 84 heavy precipitation events which occurred between August 2010 and November 2011. An algorithm which uses various TPWA thresholds derived from the 84 events is then developed and tested using dichotomous contingency table verification statistics to determine the extent to which satellite-based TPWA might be used to aid in forecasting precipitation over mesoscale domains. The hypothesis of positive and increasing TPWA preceding heavy precipitation events is supported by the analysis. Event-average TPWA rises for 36 hours and peaks at 154% of normal at the event time. The average precipitation event detected by the forecast algorithm is not of sufficient magnitude to be termed a "heavy" precipitation event; however, the algorithm adds skill to a climatological precipitation forecast. Probability of detection is low and false alarm ratios are large, thus qualifying the algorithm's current use as an aid rather than a deterministic forecast tool. The algorithm
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Accident analysis of heavy water cooled thorium breeder reactor
NASA Astrophysics Data System (ADS)
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 < 0.2% dk/k, and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The
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Radio-toxicity of spent fuel of the advanced heavy water reactor.
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.
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Ecological risk of heavy metals in sediments of the Luan River source water.
Liu, Jingling; Li, Yongli; Zhang, Bao; Cao, Jinling; Cao, Zhiguo; Domagalski, Joseph
2009-08-01
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.
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Song, Zhixin; Shan, Baoqing; Tang, Wenzhong; Zhang, Chao
2017-10-01
Soil heavy metal contents were measured in newly submerged areas of the Danjiangkou Reservoir, China. We aimed to determine the heavy metal distribution in this area and the associated ecological risk. Most of these heavy metal contents (except Pb and Mn) suggest enrichment compared with the background values of soils from Henan Province, especially As and Cd with mean geo-accumulation index (I geo ) values of 0.84 and 0.54. The spatial analysis results indicated that the highest heavy metal contents were distributed in the arable soils above 160m elevation, whereas low heavy metal contents were observed under other land-use types above 160m elevation. According to I geo and EF values, Cd was the major heavy metal contaminant in the newly submerged area, Cr, Pb and Mn mainly originated from natural geochemical sources. In contrast, Ni, Cd, As, Cu, and Zn mainly originated from anthropogenic sources. Evaluation using the potential ecological risk (PER) method indicated that PER of individual elements were low in the studied soils, and the comprehensive PER index was at a moderate level, indicating heavy metals in the soils of newly submerged areas may not threaten the water quality of Danjiangkou Reservoir, especially in winter. Copyright © 2017 Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Lu, Hongwei; Yu, Sen
2018-04-01
The rapid urbanization and industrialization in developing countries have increased pollution by heavy metals, which is a concern for human health and the environment. In this study, according to the data obtained from the monitoring stations in the Songhua River basin, the multivariate statistical analysis methods are applied to the hydrological data of the Songhua River basin in order to examine the relation between human activities and the spatio-temporal change of heavy metals (Pb and Cu) in water. By comparing the concentrations at different flow periods, the minimum Pb concentrations are found to have occurred most frequently in low flow periods while the maximum values mostly appeared in average flow periods. Moreover, the minimum Cu concentration in the water frequently occurred in high flow periods. The results show there are low Pb and Cu concentrations in upstream and downstream sections and high concentrations in mid-stream sections, and high concentrations are most frequently measured in the sections of Ashihe' downstream and estuary. Moreover, we have predicted the future (during 2018-2025) trend of the change for the heavy metals pollution in the rivers. The results demonstrated intense human activities are the most important factor causing jump features of typical heavy metal pollution in the different periods for different sections of this study area. The research would provide decision-making and planning for the Songhua River basin during the period of China's 13th Five-Year Plan.
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2004-03-03
JPL Researcher Bruce Chapman at an AirSAR station aboard NASA's DC-8 flying laboratory during the AirSAR 2004 campaign. AirSAR 2004 is a three-week expedition by an international team of scientists that will use an all-weather imaging tool, called the Airborne Synthetic Aperture Radar (AirSAR), in a mission ranging from the tropical rain forests of Central America to frigid Antarctica.
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Sakson, Grazyna; Brzezinska, Agnieszka; Zawilski, Marek
2018-04-14
Heavy metals are among the priority pollutants which may have toxic effects on receiving water bodies. They are detected in most of samples of stormwater runoff, but the concentrations are very variable. This paper presents results of study on the amount of heavy metals discharged from urban catchment in Lodz (Poland) in 2011-2013. The research was carried out to identify the most important sources of their emission and to assess the threats to receiving water quality and opportunities of their limitation. The city is equipped with a combined sewerage in the center with 18 combined sewer overflows and with separate system in other parts. Stormwater and wastewater from both systems are discharged into 18 small urban rivers. There is a need of restoration of water bodies in the city. Research results indicate that the main issue is high emission of heavy metals, especially zinc and copper, contained in stormwater. Annual mass loads (g/ha/year) from separate system were 1629 for Zn and 305 for Cu. It was estimated that about 48% of the annual load of Zn, 38% of Cu, 61% of Pb, and 40% of Cd discharged into receiving water came from separate system, respectively 4% of Zn and Cu, 10% of Pb and 11% of Cd from CSOs, and the remaining part from wastewater treatment plant. Effective reduction of heavy metals loads discharged into receiving water requires knowledge of sources and emissions for each catchment. Obtained data may indicate the need to apply centralized solution or decentralized by source control.
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NASA Astrophysics Data System (ADS)
Komure, M.; Kiyokawa, S.; Ikehara, M.; Tsutsumi, Y.; Horie, K.
2005-12-01
The Mount Bruce Supergroup is deposited from Late Archaean to Early Proterozoic in the Pilbara craton, Western Australia. It is filed the information of the period that changes from the Late Archean to the Early Proterozoic, and is the key sequences which could reconstruct the sedimentary environment because of its low metamorphic grade. The evidence of early Proterozoic global ice age as the glacial sediment is reported in this uppermost group (Martin 1999). In this study, we focus the lithological changes of the Mount Bruce Supergroup at the Beasley River - Rocklea Dome area in the Southern Pilbara. Along the Beasley River, this supergroup distributes more than 10000m thick with 5 billion years sequences, and is divided into three groups. The Fortescue Group is identified with the flood basalt to the Shallow marine or the non-marine sediment, the middle Hamersley Group rich in the banded iron formation and the acidic volcanic rock and the upper Turee Creek Group mainly of the Shallow marine sediment. Here we focused origin of the sandstone in each group, especially in the Meteorite Bore Member of Turee Creek Formation which is identified as the early snowball earth events. At the matrix of the diamictite of the Meteorite Bore Member, Origin of diamictite matrix in the Turee Creek Group sediment by the U-Pb detrital zircon geochronology by CHIME and SHRIMP2. The zircon ages points between 2.7Ga and 2.4Ga. In addtion from this matrix, TOC value indicate 0.1-0.05%, the delta 13 C value is -30--20 par mil. These evidence suggested that the organic activity might take place at during ice age.
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Ahmad, Kabir; Azizullah, Azizullah; Shama, Shama; Khattak, Muhammad Nasir Khan
2014-11-01
The present study was conducted to investigate the contamination of water, sediments, and fish tissues with heavy metals in river Panjkora at Lower Dir, Khyber Pakhtunkhwa, Pakistan. Water, sediments, and fish (Shizothorax plagiostomus) samples were collected from September 2012 to January 2013 at three different sites (upstream site at Sharigut, sewage site at Timergara, and downstream site at Sadoo) of river Panjkora. The concentrations of heavy metals in water were in the order Zn > Cu ≈ Pb > Ni ≈ Cd with mean values of 0.30, 0.01, 0.01, 0.0 and 0.0 mg/l, respectively, which were below the maximum permissible limits of WHO for drinking water. In sediments, heavy metals were found in the order Cu > Zn > Ni > Pb > Cd with mean concentrations of 50.6, 38.7, 9.3, 8, and 0.4 mg/kg, respectively. Ni and Cd were not found in any fish tissues, but Zn, Cu, and Pb were detected with the mean concentration ranges of 0.04-1.19, 0.03-0.12, and 0.01-0.09 μg/g, respectively. The present study demonstrates that disposal of waste effluents causes a slight increase in the concentration of heavy metals in river Panjkora as revealed by variation in metal concentrations from upstream to downstream site. Sewage disposal was also found to change physicochemical characteristics of Panjkora water. At present, water and fish of river Panjkora are safe for human consumption, but the continuous sewage disposal may create problems in the future.
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Conversion of deuterium gas to heavy water by catalytic isotopic exchange using wetproof catalyst
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quaiattini, R.J.; McGauley, M.P.; Burns, D.L.
The invention at Chalk River Nuclear Laboratories of a simple method of wetproofing platinum catalysts allows them to retain their activity in liquid water. High performance catalysts for the hydrogen-water isotope exchange reaction that remain active for years can now be routinely produced. The first commercial application using the ordered-bed-type wetproofed isotope exchange catalyst developed and patented by Atomic Energy of Canada Ltd. has been successfully completed. Approximately 9100 m/sup 3/ of deuterium gas stored at Brookhaven National Laboratory was converted to high grade heavy water. Conversion efficiency exceeded 99.8%. The product D/sub 2/O concentration was 6.7 percentage points highermore » than the feed D/sub 2/ gas.« less
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Montes-Botella, C; Tenorio, M D
2003-11-01
The Iberian Pyrite Belt is the largest mass of sulfide and manganese ores in Western Europe. Its sulfide oxidation is the origin of a heavily acidic drainage that affects the Odiel River in southwestern Huelva (Spain). To assess physicochemical, contamination parameters, heavy metal distribution and its seasonal variation in the upper Odiel River and in El Lomero mines, three water samplings were undertaken and analyzed between July 1998 and November 1999. Water from the Odiel River in the polluted zone showed low pH values (2.76-3.51), high heavy metal content, and high values of conductivity (1410-3648 microS/cm) and dissolved solids (1484-5602 mg/L). Principal Component Analysis (PCA) showed that variables related with the products of the pyrite oxidation and the salts that are solubilized by the high acidity generated in the oxidation of sulfides, grouped in the first component, accounted for 40.88% of total variance, and were the main influential factor in physicochemical water sample properties. The second influential factor was minority metals (nickel, cobalt, cadmium). Heavy metals showed three different seasonal patterns, closely related with saline efflorescences formed next to the river bed: majority metals (iron, copper, manganese, zinc); minority metals (lead, nickel, cobalt, cadmium); and chromium, which had a distinctive behavior.
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Ghazy, Haneen A; Abdel-Razek, Mohamed A S; El Nahas, Abeer F; Mahmoud, Shawky
2017-09-01
Alteration of immunological function of an aquatic organism can be used as an indicator for evaluating the direct effect of exposure to pollutants. The aim of this work is to assess the impact of complex water pollution with special reference to Pyrethroid pesticides and heavy metals on mRNA transcript levels of Metallothionine and some immune related genes of Nile tilapia (Oreochromas Niloticus). Residues of six heavy metals and six Pyrethroid were assessed in water as well as fish tissues at three different sites of Lake Burullus, located at Northern Egypt. Variations of water physicochemical properties associated with different levels of heavy metals at the three different sections were recorded. Tissue residues of Fe, Mn and Zn, Cu, Ni exceed water levels in contrast to elevated water level of Pb. All assessed Pyrethroids are detected in fish tissue samples with higher concentration (3-42 folds) than that found in water samples especially Cypermethrin. Significant down-regulation of expression levels of metallothionein (MT) at the three sections of the lake was observed. The expression of immune related genes (IgM) and inflammatory cytokines (TNF, IL.8 and IL.1) were affected. IgM and TNF were significantly down-regulated at eastern and western section of the lake; meanwhile the expression of IL8 is down regulated at the three sections of the lack. IL1 was significantly up-regulated at eastern and middle sections. We conclude that, variable gene expression of MT and immune-related genes at the three sections of the lack impose different response to complex water pollution in relation to variable aquatic environment. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Rajeshkumar, Sivakumar; Liu, Yang; Zhang, Xiangyang; Ravikumar, Boopalan; Bai, Ge; Li, Xiaoyu
2018-01-01
The present study, seasonal pollution of heavy metals (Pb, Cd, Cr and Cu) in water, sediment, tissues of fish Carassius carassius and oyster Crassostrea gigas were determined at seven sampling sites from Meiliang Bay, Taihu Lake during one year calendar, 2016. The total heavy metal concentrations in water samples were higher in winter and summer than in spring and autumn season, whereas in sediment they were higher in winter and summer seasons, respectively. The trend of metal mean contents found in the fish and oyster were in decreasing order of Pb > Cu > Cr > Cd and Pb > Cu > Cr > Cd, respectively. The tissues of fish and oyster captured during winter and summer accumulated a higher significant different amount of metals relative to other season, which was attributed to a higher influx of agricultural waste, sewage and sludge by heavy rainfall and floods. In addition, the pollution load index (PLI) values were above one (>1), indicating an advanced decline of the sediment quality, and contamination factor (CF) confirmed that the sediment samples were moderate to high contamination by Pb and Cr. Thus, comparative studies with seasonal pollution of heavy metals in Meiliang Bay of Lake Taihu regions indicate considerable heavy metal enrichment in water, sediments as well as in various organs of fish and oyster. Finally, our results indicated that the metal concentration values increased statistically significant different related to season (p < 0.001). The determination of heavy metal stress biomarkers in fish along with seasonal variations may serve as a convenient approach during pollution bio-monitoring programme. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Non-Invasive Acoustic-Based Monitoring of Heavy Water and Uranium Process Solutions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pantea, Cristian; Sinha, Dipen N.; Lakis, Rollin Evan
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.
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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.
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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.
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Influence of supercritical water treatment on heavy metals in medical waste incinerator fly ash.
Bo, Da; Zhang, Fu-Shen; Zhao, Lijuan
2009-10-15
In this work, medical waste (MW) incinerator fly ashes from different types of incinerators were subjected to supercritical water (SCW) and SCW+H(2)O(2) (SCWH) treatments. Sequential extraction experiments showed that, after SCW treatment, heavy metals in exchangeable and carbonate forms in the ashes could be transferred into other relatively stable forms, e.g., Ba and Cr into residual fraction, Cu and Pb into organic matter fraction. SCWH treatment could stabilize heavy metals in Fe-Mn oxides and residual fractions. However, the behavior of As was quite different from heavy metals, which could be leached out from residue fraction after SCW and SWCH treatments. The leached As tended to absorb onto Fe-Mn oxides and organic matters under near neutral environment, but it could react with Ca(2+) at lower pH, increasing the mobility of this element. Therefore, it is necessary to neutralize acidic ash to near neutral condition before subjecting it to SCW and SCWH treatments so as to effectively stabilize hazardous elements in the ash. Consequently, it is believed that SCWH treatment is an effective alternative for hazardous elements detoxification in MW fly ash.
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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.
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NASA Astrophysics Data System (ADS)
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.
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Rajfur, Małgorzata; Kłos, Andrzej; Wacławek, Maria
2010-11-01
Kinetics of heavy-metal ions sorption by alga Spirogyra sp. was evaluated experimentally in the laboratory, using both the static and the dynamic approach. The metal ions--Mn(2+), Cu(2+), Zn(2+) and Cd(2+)--were sorbed from aqueous solutions of their salts. The static experiments showed that the sorption equilibria were attained in 30 min, with 90-95% of metal ions sorbed in first 10 min of each process. The sorption equilibria were approximated with the Langmuir isotherm model. The algae sorbed each heavy metal ions proportionally to the amount of this metal ions in solution. The experiments confirmed that after 30 min of exposition to contaminated water, the concentration of heavy metal ions in the algae, which initially contained small amounts of these metal ions, increased proportionally to the concentration of metal ions in solution. The presented results can be used for elaboration of a method for classification of surface waters that complies with the legal regulations. Copyright © 2010 Elsevier B.V. All rights reserved.
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Ecological risk of heavy metals in sediments of the luan river source water
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.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Muramoto, S.; Oki, Y.
1984-10-01
In a previous paper, the ability of water hyacinth to remove toxic heavy metals, cadmium, lead, and mercury, from a metal-containing solution was reported. However, information on the effects of surface-active agents on the metal uptake from waste water by water hyacinth is insufficient. Surface-active agents including anionic detergents have been found in lake, ponds, and rivers polluted by waste from industry and municipal sewage treatment plants. The present study examines the uptake of cadmium or nickel in the presence of the anionic detergent sodium dedecyl sulfate.
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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.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Luker, J.A.; Adler, L.B.; Hobaica, E.C.
1959-01-23
The purpose of this investigation was to determine the reaction characteristics of satuated mixtures of knall gas (stoichiometric mixture of hydrogen and oxygen) --steam and mixtures of heavy knall gas (stoichm-ometric mixture of deuterion and oxygen) saturated with heavy water. These mixtues were studied experimentally over composition ranges from no reaction limit to enriched compositions which supported detonations. (auth)
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Mishra, Virendra K; Upadhyay, Alka R; Tripathi, B D
2009-09-01
Four crop plants Oryza sativa (rice), Solanum melongena (brinjal), Spinacea oleracea (spinach) and Raphanus sativus (radish) were grown to study the impact of secondary treated municipal waste water irrigation. These plants were grown in three plots each of 0.5 ha, and irrigated with secondary treated waste water from a sewage treatment plant. Sludge from the same sewage treatment plant was applied as manure. Cultivated plants were analyzed for accumulation of heavy metals and pesticides. Results revealed the accumulation of six heavy metals cadmium (Cd), chromium (Cr), iron (Fe), copper (Cu), nickel (Ni), and zinc (Zn) as well as two pesticides [1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane; DDT] and benzene hexa chloride (BHC). Order of the plants for the extent of bioaccumulation was S. oleracea > R. sativus > S. melongena > O. sativa. The study has shown the secondary treated waste water can be a source of contamination to the soil and plants.
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Accident analysis of heavy water cooled thorium breeder reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yulianti, Yanti; Su’ud, Zaki; Takaki, Naoyuki
2015-04-16
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 < 0.2% dk/k,more » and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow
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Haloi, Nabanita; Sarma, H P
2012-10-01
A study was conducted to evaluate the heavy metal contamination status of groundwater in Brahmaputra flood plain Barpeta District, Assam, India. The Brahmaputra River flows from the southern part of the district and its many tributaries flow from north to south. Cd, Fe, Mn, Pb, and Zn are estimated by using atomic absorption spectrometer, Perkin Elmer AA 200. The quantity of heavy metals in drinking water should be checked time to time; as heavy metal accumulation will cause numerous problems to living being. Forty groundwater samples were collected mainly from tube wells from the flood plain area. As there is very little information available about the heavy metal contamination status in the heavily populated study area, the present work will help to be acquainted with the suitability of groundwater for drinking applications as well as it will enhance the database. The concentration of iron exceeds the WHO recommended levels of 0.3 mg/L in about 80% of the samples, manganese values exceed 0.4 mg/L in about 22.5% of the samples, and lead values also exceed limit in 22.5% of the samples. Cd is reported in only four sampling locations and three of them exceed the WHO permissible limit (0.003 mg/L). Zinc concentrations were found to be within the prescribed WHO limits. Therefore, pressing awareness is needed for the betterment of water quality; for the sake of safe drinking water. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16).
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Yang, Zhenzhou; Tian, Sicong; Ji, Ru; Liu, Lili; Wang, Xidong; Zhang, Zuotai
2017-10-01
The present study systemically investigated the effect of a water-washing process on the removal of harmful chlorides, sulfates, and heavy metals in the air pollution control (APC) residue from municipal solid wastes incineration (MSWI), for sake of a better reuse and disposal of this kind of waste. In addition, the kinetic study was conducted to reveal the releasing mechanism of relevant element in the residue. The results show that, over 70wt.% of chlorides and nearly 25wt.% of sulfates in the residue could be removed by water washing. Based on an economical consideration, the optimal operation conditions for water washing of APC residue was at liquid/solid (L/S) ratio of 3mL:1g and extracting time of 5min. As expected, the concentrations of Co, Cr, Fe, Ni, V and Cu in the washing effluent increased with time during the washing process. However, the extracting regime differs among different heavy metals. The concentrations of Ba and Mn increased firstly but declined afterwards, and concentrations of Pb and Zn gradually declined while Cd and As kept constant with the increase of extracting time. It is worth mentioning that the bubbling of CO 2 into the washing effluent is promisingly effective for a further removal of Pb, Cu and Zn. Furthermore, kinetic study of the water washing process reveals that the extracting of heavy metals during water washing follows a second-order model. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Isotope effect in heavy/light water suspensions of optically active gold nanoparticles
NASA Astrophysics Data System (ADS)
Kutsenko, V. Y.; Artykulnyi, O. P.; Petrenko, V. I.; Avdeev, M. V.; Marchenko, O. A.; Bulavin, L. A.; Snegir, S. V.
2018-04-01
Aqueous suspensions of optically active gold nanoparticles coated with trisodium citrate were synthesized in light (H2O) water and mixture of light and heavy (H2O/D2O) water using the modified Turkevich protocol. The objective of the paper was to verify sensitivity of neutron scattering methods (in particular, neutron reflectometry) to the potential isotope H/D substitution in the stabilizing organic shell around particles in colloidal solutions. First, the isotope effect was studied with respect to the changes in the structural properties of metal particles (size, shape, crystalline morphology) in solutions by electron microscopy including high-resolution transmission electron microscopy from dried systems. The structural factors determining the variation in the adsorption spectra in addition to the change in the optical properties of surrounding medium were discussed. Then, neutron reflectometry was applied to the layered nanoparticles anchored on a silicon wafer via 3-aminopropyltriethoxysilane molecules to reveal the presence of deuterated water molecules in the shell presumably formed by citrate molecules around the metallic core.
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Dobaradaran, Sina; Soleimani, Farshid; Nabipour, Iraj; Saeedi, Reza; Mohammadi, Mohammad Javad
2018-01-01
In this study we report the concentration levels of heavy metals (including Pb, Cd, Hg, Cr, Ni, Fe, Mn, Cu) in ballast water of commercial ships, entering Bushehr port for the first time in the region of the Persian Gulf. The concentration levels of Cu and Fe in all samples of the ballast water were higher compared with the coastal waters of Bushehr port. In the case of Cd, 76.47% of samples had higher concentration level compared with the coastal waters of Bushehr port. Results showed that in a long term the ballast water has the potential to change the chemical quality in marine environments and also may affect the human health and marine ecosystem where ships discharge their ballast water. Therefore, permanent monitoring as well as treatment of ballast water before discharging is crucial to keep the marine environment health. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Chen, Yueh-Min; Li, Hong-Chun; Tsao, Tsung-Ming; Wang, Liaug-Chi; Chang, Yin
2014-11-01
Studies of heavy metal contamination and ecological risk in estuaries are an important emerging area of environmental science. However, there have been few detailed studies of heavy metal contamination that concern the spatial variation of heavy metal levels in water, sediment, and oyster tissue. Because of the effective uptake of heavy metals, cultured oysters are a cheap and effective subject for study. This study, conducts an experiment in the Er-Ren river to examine the biological uptake of heavy metals in farmed, cultured oysters. The distribution of copper, zinc, lead, cadmium, and arsenic concentrations in water, sediment, and oysters from the Er-Ren river is also evaluated. By sequential extraction of the sediments, the following order of mobilities is found for heavy metals Pb > Cd > As > Zn > Cu. The highest percentages of heavy metals are found in the residual phase. The mean uptake rates for young oysters are 7.24 mg kg(-1) day(-1) for Cu and 94.52 mg kg(-1) day(-1) for Zn, but that for adult oyster is 10.79 mg kg(-1) day(-1) for Cu and 137.24 mg kg(-1) day(-1) for Zn. With good policies and management, the establishment of cultured oyster frames in these contaminated tributaries and near shore environments is a potential method for removing Cu and Zn and protecting the coast.
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Anwar, Sumera; Nawaz, Muhammad Farrakh; Gul, Sadaf; Rizwan, Muhammad; Ali, Shafaqat; Kareem, Arshaad
2016-09-01
Heavy metal uptake and accumulation behavior in dietary vegetables irrigated with sewage waters is an important issue worldwide. The main objective of this study was to examine and compare the physiological and growth responses of leafy vegetables irrigated with sewage water. A pot experiment was conducted in a wire house with three leafy vegetables, coriander (Coriandrum sativum), mint (Mentha arvensis), and fenugreek (Trigonella foenum), grown under ambient conditions. Plants were irrigated with different concentrations, 0, 50 (T 1), and 100 % (T 2), of sewage water. After harvesting, morphological and physiological parameters of plants were measured. Heavy metal (Cd, Cu, Pb, and Zn) concentrations in the sewage water were found much higher than safer limits. The results revealed that the highest plant biomass and lowest metal contents were observed in control treatments in all studied vegetables. The biomass of all the vegetables were negatively affected when irrigated with sewage water. In T 2, coriander accumulated maximum Cd (μg g(-1) DW) in shoots (4.97) as compared to other vegetables. The maximum Pb and Cu concentrations were accumulated in mint roots (44 and 3.9, respectively) as compared to coriander and fenugreek. Zinc was accumulated in the sequence of leaves > roots > shoots under polluted water irrigation. The concentrations of potassium increased in leaves, shoots, and roots in all vegetables, while phosphorous concentrations varied with species and plant parts with increasing sewage water concentration. It was found that the leafy vegetables grown with sewage water irrigation may cause severe human health problems.
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Ahammed, M Mansoor; Meera, V
2010-09-15
The present study was conducted to compare the performance of a dual-media filter consisting of manganese oxide-coated (MOCS) and iron hydroxide-coated sand (IOCS) with that of IOCS filter and uncoated sand filter in treating water contaminated by microorganisms, heavy metals and turbidity with a view to its use in simple household water purification devices in developing countries. Long-duration column tests were conducted using two natural waters namely, roof-harvested rainwater and canal water. Performance of the filters showed that dual-media filter was more efficient in removing bacteria and heavy metals compared to IOCS filter, while uncoated sand filter showed very poor performance. The average effluent levels for dual-media filter when tested with rainwater were: turbidity 1.0+/-0.1 NTU; total coliforms 3+/-2 MPN/100 mL; heterotrophic plate count 170+/-20 CFU/mL; zinc 0.06+/-0.01 mg/L, while that for IOCS filter were: turbidity 1.0+/-0.1 NTU; total coliforms 4+/-2 MPN/100 mL; heterotrophic plate count 181+/-37 CFU/mL; zinc 0.20+/-0.07 mg/L. Similar results were obtained for canal water also. Up to 900 bed volumes (BV) could be treated without affecting the efficiency in the case of rainwater, while the filter operation had to be terminated after 500 BV due to excessive headloss in the case of canal water. The study thus showed the potential of the dual-media for use in low-cost household water filters for purification of natural waters. Copyright 2010 Elsevier B.V. All rights reserved.
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Strungaru, Stefan-Adrian; Nicoara, Mircea; Jitar, Oana; Plavan, Gabriel
2015-01-01
Heavy metals like Cu, Cd, Pb, Ni, Co and Cr can naturally be found almost all over this planet in various amounts. Urban activities such as heavy metal industry, traffic and waste can rapidly increase the metal concentrations in a fresh water ecosystem. This study was done in natural conditions to capture as many aspects in heavy metals pollution and bioremediation of Nicolina River, Romania considered a stream model which is under anthropogenic pressure. Water, sediment and leaves samples of Typha latifolia L. were collected during October 2013 and analyzed in order to assess certain heavy metals (Cu, Cd, Pb, Ni, Co and Cr) from each sampling site using GF-HR-CS-AAS with platform. Heavy metals in significant concentrations in cattail samples were correlated with the water parameters to show the possibility to use the cattail leaves as indicators in heavy metals pollution with potential in bioremediation because they can be easily harvested in autumn and this species is spread worldwide. The levels of metals concentrations in leaves were: Cu > Ni > Cr > Pb > Co knowing that copper is an essential element for plants. The sampling time was important to draw the river diagnosis for heavy metal pollution. The samples were collected, from river, after more than 60 days without rain same as a "human patient" prepared for blood test. Cobalt was considered the metal marker because it was an element with the lowest level of usage in the city. Compared with it only lead, cadmium and copper were used intensively in the industrial activities. T. latifolia L. can be use as an indicator for the health of the studied stream and it was noticed that the heavy metals were not accumulated, although the metal uptake was influenced by sediments and water parameters. The alkalinity of the studied river acts as an inhibitor in the bioremediation process of cattail for cadmium and copper. Lead was uptake by leaves and the water parameters influenced it but it wasn
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Heavy metals and arsenic content in water along the southern Caspian coasts in Iran.
Abadi, Mohammad; Zamani, Abbasali; Parizanganeh, Abdolhossein; Khosravi, Younes; Badiee, Hamid
2018-06-06
Due to the importance of pollution monitoring in marine ecosystems and lack of a coherent and systematic investigation of heavy metal ions along the southern shores of the Caspian Sea, in the present study, the amount of these metals and As ions in coastal waters along its 780-km-long coast in Iran have been studied. Heavy metals (cobalt, nickel, copper, zinc, cadmium, mercury, lead) and a poisonous metalloid (arsenic) were selected in 59 sampling stations and determined using differential pulse polarography method. The multivariate statistical tools were applied to describe and interpret the experimental data. The overall mean concentrations of studied metals (in microgram per liter; μg L -1 ) in the samples were found in the order Zn (10.9) > Ni (7.4) > Cu (5.5) > Pb (1.9) > Hg (1.4) > As (1.3) > Co (1.1) > Cd (0.2). The results when compared with reported international standards confirmed that the sampled waters do contain some of these elements above the suggested maximum permissible limits. Hg and Cu were detected in 54.2 and 72.9% of the samples, almost all above the permissible limits. Ni, Zn, Pb, and Co were detected in 100, 96.6, 93.2, and 88.1%, respectively, while 8.5, 22.0, 3.4, and 1.7% were above the permissible limits. Cd and As were present in 61 and 93% of the samples, and their concentrations were higher than the rate presented by Russian System of Management Chemicals (RSMC). In addition, spatial distribution of heavy metal concentrations showed that Gorgan Bay is an ecosystem serving as a filter, trapping natural and anthropogenic materials that are brought from industrial, commercial, and urbanized areas. The multivariate data analysis reveals that Caspian Sea is contaminated by both anthropogenic as well as pedo-geochemical sources.
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Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution
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. 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. PMID:24818124
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Multidrug and heavy metal-resistant Raoultella planticola isolated from surface water.
Koc, Serkan; Kabatas, Burak; Icgen, Bulent
2013-08-01
A surface water isolate of Raoultella sp. having both multidrug- and multimetal-resistant ability was isolated and identified as Raoultella planticola. R. planticola displayed resistance to 15 drugs like ampicillin, amoxicillin/clavulanic acid, aztreonam, erythromycin, imipenem, oxacillin, pefloxacin, penicillin, piperacillin, piperacillin/tazobactam, rifampin, sulbactam/cefoperazone, ticarsillin, ticarsillin/clavulanic acid, vancomycin, and to 11 heavy metals like aluminum, barium, copper, iron, lead, lithium, manganese, nickel, silver, strontium, and tin. The multidrug and multi-metal-resistant R. planticola may remain present in the environment for a long time. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.
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Heavy Metal Displacement in Chelate-Assisted Phytoremediation of Biosolids Soil
NASA Astrophysics Data System (ADS)
Kirkham, M. B.; Liphadzi, M. S.
2005-05-01
Heavy metals in biosolids (sewage sludge) applied to land contaminate the soil. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with biosolids following solubilization with chelates. The objective of this work was to determine the mobility of heavy metals, as affected by a chelate, in soil (Haynie very fine sandy loam) from a 25-year old sludge farm. Soil columns (105 cm long; 39 cm in diameter) either had a plant (hybrid poplar; Populus deltoides Marsh. x P. nigra L.) or no plant. When the poplars were 144 days old, the tetrasodium salt of the chelating agent EDTA (ethylenediamine-tetraacetic acid) was irrigated onto the soil at a rate of 1 g per kg of soil. Drainage water, soil, and plants were analyzed for three toxic heavy metals (Cd, Ni, Pb) and four essential heavy metals (Cu, Fe, Mn, Zn). Without EDTA, concentrations of the seven heavy metals in the leachate from columns with or without plants were low or below detection limits. With or without plants, the EDTA mobilized all heavy metals and increased their concentration in drainage water. Without plants, the concentrations of Cd, Cu, Fe, Pb, and Zn in the leachate from columns with EDTA were above drinking-water standards. (There is no drinking-water standard for Ni.) The presence of poplar plants in the soil reduced the concentrations of Cu, Fe, and Zn in the leachate so it fell within drinking-water standards. Concentrations of Cd and Pb in the leachate remained above drinking-water standards with or without plants. At harvest (124 days after the EDTA application), total concentration of each heavy metal in the soil at different depths in the columns with EDTA was similar to that in the columns without EDTA. The chelate did not affect the concentration of heavy metals in the roots, stems, or leaves
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Prevalence of exposure of heavy metals and their impact on health consequences.
Rehman, Kanwal; Fatima, Fiza; Waheed, Iqra; Akash, Muhammad Sajid Hamid
2018-01-01
Even in the current era of growing technology, the concentration of heavy metals present in drinking water is still not within the recommended limits as set by the regulatory authorities in different countries of the world. Drinking water contaminated with heavy metals namely; arsenic, cadmium, nickel, mercury, chromium, zinc, and lead is becoming a major health concern for public and health care professionals. Occupational exposure to heavy metals is known to occur by the utilization of these metals in various industrial processes and/or contents including color pigments and alloys. However, the predominant source resulting in measurable human exposure to heavy metals is the consumption of contaminated drinking water and the resulting health issues may include cardiovascular disorders, neuronal damage, renal injuries, and risk of cancer and diabetes. The general mechanism involved in heavy metal-induced toxicity is recognized to be the production of reactive oxygen species resulting oxidative damage and health related adverse effects. Thus utilization of heavy metal-contaminated water is resulting in high morbidity and mortality rates all over the world. Thereby, feeling the need to raise the concerns about contribution of different heavy metals in various health related issues, this article has discussed the global contamination of drinking water with heavy metals to assess the health hazards associated with consumption of heavy metal-contaminated water. A relationship between exposure limits and ultimate responses produced as well as the major organs affected have been reviewed. Acute and chronic poisoning symptoms and mechanisms responsible for such toxicities have also been discussed. © 2017 Wiley Periodicals, Inc.
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Biosorption of heavy metals and uranium from dilute solutions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneider, I.A.H.; Misra, M.; Smith, R.W.
1995-08-01
Eichhornia crassipes approaches being a scourge in many parts of the world, choking waterways and hindering transport upon them. At the same time it is known to readily abstract heavy metal ions from water and, thus, aids in the removal of heavy metals found in such waters. This paper considers the possibility of using specific parts of the plant as an inexpensive adsorbent for the removal of heavy metals from contaminated chemical and mining industry waste waters. In particular the root of the plant was found to be an excellent accumulator of heavy metal ions including uranium from solution. Itmore » is also suggested that dried roots of the plant might be placed in simple bags and used in a very low cost metal ion removal system.« less
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Zhao, Ye; Han, Sha-Sha; Chen, Zhi-Fan; Liu, Jing; Hu, Honq-Xia
2015-01-01
After years of irrigating farmland with wastewater, concern is increasing about health risks from heavy metals contaminating wheat grown in sewage-irrigated soils in suburban areas of Beijing, China. The study discussed in this article aimed to compare the characteristics of heavy metal distribution in a sewage-irrigated "soil-wheat" system with those from a clean-water-irrigated area by collecting and analyzing samples from both areas. The results indicated that the average concentrations of copper, chromium, lead, and zinc in sewage-irrigated soil were higher than the values in the clean-water-irrigated region. Irrigation with wastewater could lead to increased bioconcentration factors. Therefore, issues of food contamination caused by sewage irrigation deserve more attention.
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Heavy metal displacement in chelate-irrigated soil during phytoremediation
NASA Astrophysics Data System (ADS)
Madrid, F.; Liphadzi, M. S.; Kirkham, M. B.
2003-03-01
Heavy metals in wastewater sewage sludge (biosolids), applied to land, contaminate soils. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with and without roots following solubilization with chelates. The objective of this work was to determine the mobility of heavy metals in biosolids applied to the surface of soil columns (76 cm long; 17 cm diam.) with or without plants (barley; Hordeum vulgare L.). Three weeks after barley was planted, all columns were irrigated with the disodium salt of the chelating agent, EDTA (ethylenediamine tetraacetic acid) (0.5 g/kg soil). Drainage water, soil, and plants were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, Zn). Total concentrations of the heavy metals in all columns at the end of the experiment generally were lower in the top 30 cm of soil with EDTA than without EDTA. The chelate increased concentrations of heavy metals in shoots. With or without plants, the EDTA mobilized Cd, Fe, Mn, Ni, Pb, and Zn, which leached to drainage water. Drainage water from columns without EDTA had concentrations of these heavy metals below detection limits. Only Cu did not leach in the presence of EDTA. Even though roots retarded the movement of Cd, Fe, Mn, Ni, Pb, and Zn through the EDTA-treated soil from 1 d (Cd) to 5 d (Fe), the drainage water from columns with EDTA had concentrations of Cd, Fe, Mn, and Pb that exceeded drinking water standards by 1.3, 500, 620, and 8.6 times, respectively. Because the chelate rendered Cd, Fe, Mn, Ni, Pb, and Zn mobile, it is suggested that the theory for leaching of soluble salts, put forward by Nielsen and associates in 1965, could be applied to control movement of the heavy metals for maximum uptake during chelate-assisted phytoremediation.
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Singh, Ravendra Kumar; Chavan, Sugandha L; Sapkale, Pravin H
2007-06-01
Live feeds, especially Tubifex spp., which are collected from a wide variety of polluted habitats, are used by aquarium fish keepers in India. These habitats receive domestic sewage and industrial wastes from nearby residential and industrial areas. Reports of morbidity and mortality from aquarium fish culturists in and around Mumbai led to the present investigations on the ecology of these habitats with a view to assess the water quality, presence of heavy metals in the environment and their bioaccumulation in Tubifex worms, and to examine whether these habitats could be exploited to meet the demand of the industry. Six natural red worm (Tubifex spp.) collection centres in Mumbai and Thane districts of Maharashtra state in India constituting a major source of live Tubifex supply to aquarium fish industry were evaluated for pollution, heavy metal concentration in water, sediments and in the body tissues of Tubifex. Data revealed the presence of heavy metals in water and sediments at collection sites and bioaccumulation of cadmium, iron, lead, zinc and copper in body tissues of Tubifex worms. Cadmium ranged from 2.38 to 7.21 mg/kg, iron 671.9 to 5738 mg/kg, lead 14.95 to 33.49 mg/kg, zinc 60.20 to 166.60 mg/kg and copper 29.38 to 108.90 mg/kg of dry Tubifex worms. The study suggests that all the six collection sites are polluted and the red worms contaminated with heavy metals and hence, unfit for use in aquaria or feeding any variety of fish or crustaceans in the hatcheries.
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Sounthararajah, Danious P; Loganathan, Paripurnanda; Kandasamy, Jaya; Vigneswaran, Saravanamuthu
2015-08-27
Heavy metals constitute some of the most dangerous pollutants of water, as they are toxic to humans, animals, and aquatic organisms. These metals are considered to be of major public health concern and, therefore, need to be removed. Adsorption is a common physico-chemical process used to remove heavy metals. Dissolved organic carbon (DOC) and suspended solids (SS) are associated pollutants in water systems that can interact with heavy metals during the treatment process. The interactions of DOC and SS during the removal of heavy metals by granular activated carbon were investigated in batch and fixed-bed column experiments. Batch adsorption studies indicated that Langmuir adsorption maxima for Pb, Cu, Zn, Cd, and Ni at pH 6.5 were 11.9, 11.8, 3.3, 2.0, and 1.8 mg/g, respectively. With the addition of humic acid (HA) (DOC representative), they were 7.5, 3.7, 3.2, 1.6, and 2.5 mg/g, respectively. In the column experiment, no breakthrough (complete removal) was obtained for Pb and Cu, but adding HA provided a breakthrough in removing these metals. For Zn, Cd and Ni, this breakthrough occurred even without HA being added. Adding kaolinite (representative of SS) had no effect on Pb and Cu, but it did on the other metals.
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Investigation of heavy metals release from sediment with bioturbation/bioirrigation.
He, Yi; Men, Bin; Yang, Xiaofang; Li, Yaxuan; Xu, Hui; Wang, Dongsheng
2017-10-01
Bioturbation/bioirrigation can affect the remobilization of metals from sediments. In this study, experiments were performed to examine the effect of bioturbation/bioirrigation by different organisms on cadmium (Cd), copper (Cu), zinc (Zn) and lead (Pb) releasing from the spiked sediment. The diffusive gradient in thin films technique (DGT) revealed that at the end of exposure time, the labile heavy metals concentrations in the pore water for all metal and organisms combinations except Cu and chironomid larvae were much lower than that in the control group. However, the concentrations of heavy metals detected by the DGT were virtually indistinguishable among the treatments with tubificid, chironomid larvae and loach. The correlation analysis of heavy metals with iron (Fe) and manganese (Mn) suggested that Cd, Zn and Pb were most likely bound as Fe-Mn oxidation form in the pore water, but Cu was in other forms. After 28 d of exposure, bioturbation/bioirrigation produced a significant release of particulate heavy metals into the overlying water, especially in the treatment with loach. The bioturbation/bioirrigation impact on the Pb remobilization was less than the other three heavy metals. The effects of bioturbaiton/bioirrigation on the heavy metals remobilization in the sediment were complex that with studying the heavy metals remobilization in the sediment and water interface, the biological indicators should be recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Understanding THz spectra of aqueous solutions: glycine in light and heavy water.
Sun, Jian; Niehues, Gudrun; Forbert, Harald; Decka, Dominique; Schwaab, Gerhard; Marx, Dominik; Havenith, Martina
2014-04-02
THz spectroscopy of aqueous solutions has been established as of recently to be a valuable and complementary experimental tool to provide direct insights into the solute-solvent coupling due to hydrogen-bond dynamics involving interfacial water. Despite much experimental progress, understanding THz spectra in terms of molecular motions, akin to mid-infrared spectra, still remains elusive. Here, using the osmoprotectant glycine as a showcase, we demonstrate how this can be achieved by combining THz absorption spectroscopy and ab initio molecular dynamics. The experimental THz spectrum is characterized by broad yet clearly discernible peaks. Based on substantial extensions of available mode-specific decomposition schemes, the experimental spectrum can be reproduced by theory and assigned on an essentially quantitative level. This joint effort reveals an unexpectedly clear picture of the individual contributions of molecular motion to the THz absorption spectrum in terms of distinct modes stemming from intramolecular vibrations, rigid-body-like hindered rotational and translational motion, and specific couplings to interfacial water molecules. The assignment is confirmed by the peak shifts observed in the THz spectrum of deuterated glycine in heavy water, which allow us to separate the distinct modes experimentally.
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Wang, Ye-Chun; Lei, Bo; Yang, San-Ming; Zhang, Sheng
2012-02-01
To investigate the effect of 175 m trial impounding (2008 and 2009) of the Three Gorges Reservoir on soil heavy metals, three draw-down areas with similar geological environment and history of land-use in Zhongxian County were chosen. Altogether 36 surface soil samples (including 0-10 cm and 10-20 cm soil layer) from water-level altitude of 160 m and 170 m were obtained, and their heavy metals concentrations (As, Cd, Cr, Cu, Ni, Pb and Zn) were measured by the X-ray fluorescence spectrometric method. Geoaccumulation index (I(geo)) and Håkanson potential ecological risk index were applied to assess the heavy metals pollution status and potential ecological risk, respectively. Results indicated that although the inundation period of 160 m was 224 d longer than that of 170 m, significant difference in concentrations of heavy metals were not found between the two water-level altitudes. Except for Cd, most of the heavy metals highly related with each other positively. According to the geoaccumulation index, the pollution extent of the heavy metals followed the order: As > Cd > Cu > Ni > Zn = Pb > Cr. The I(geo) value of As, Cd and Cu were 0.45, 0.39 and 0.06, respectively, indicating that the soil was only lightly polluted by these heavy metals. Håkanson single potential ecological risk index followed the order: Cd > As > Cu > Pb > Ni > Cr > Zn. Cd with E(i) values of 59.10, had a medium potential for ecological risk,while As, Cr, Cu, Pb, Ni and Zn only had a light potential. Consequently, although As, Cd and Cu were the major heavy metals with potential ecological risk for surface soil pollution in the draw-down areas in Zhongxian County, the Three Gorges Reservoir.
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Mafalda, Ana Cardeira; da Câmara, Rodrigo Bettencourt; Strzelec, Patrick; Schiavon, Nick; Mirão, José; Candeias, António; Carvalho, Maria Luísa; Manso, Marta
2015-02-01
The artwork "Smoke Rings: Two Concentric Tunnels, Non-Communicating" by Bruce Nauman represents a case study of corrosion of a black patina-coated Al-alloy contemporary artwork. The main concern over this artwork was the widespread presence of white spots on its surface. Alloy substrate, patina, and white spots were characterized by means of energy-dispersive X-ray fluorescence and scanning electron microscopy with energy-dispersive spectroscopy. Alloy substrate was identified as an aluminum alloy 6,000 series Al-Si-Mg. Patina's identified composition confirmed the documentation provided by the atelier. Concerning the white spots, zircon particles were found on patina surface as external elements.
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Performance of mesoporous organosilicates on the adsorption of heavy oil from produced water
NASA Astrophysics Data System (ADS)
Twaiq, Farouq A.; Nasser, Mustafa S.; Al-Ryiami, Samyia; Al-Ryiami, Hanan
2012-09-01
The performance of mesoporous organosilicate materials in removal of soluble oil from wastewater is investigated. The aim of the study is to evaluate the oil adsorption over organosilicate prepared using pre-synthesis methods and compare the results with adsorption over pure siliceous mesoporous material. The materials were prepared using sol-gel technique using Dodecylamine (D) and Cetyltrimethylammonium bromide (CTAB) as surfactant templates, and Tetraethylorthosilicate (TEOS) as silica precursor. The as-synthesized mesoporous materials were treated using three different methods to remove the surfactant from the mesoporous silica including calcinations method for total removal of the surfactant, the water vapor stripping and ethanol vapor stripping were used for partial removal of the surfactants. The synthesized materials were characterized using X-ray diffraction (XRD) and nitrogen adsorption. The materials were tested for heavy oils removal from oil-water solution. The results showed that neutral surfactant organosilicates have less adsorption compare to cationic surfactant organosilicates. The results also showed that among organosilicates prepared using neutral surfactant, treated organosilicate by ethanol vapor have the highest activity in removing the oil from the oil-water solution.
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Liu, She-Jiang; Jiang, Jia-Yu; Wang, Shen; Guo, Yu-Peng; Ding, Hui
2018-03-15
Stabilization/Solidification (S/S) can be regarded as necessary for remediation of heavy metal contaminated soil. There is, however, solid agent is not very convenient to use. Water-soluble thiourea-formaldehyde (WTF) is a novel chelating agent, which has more practical applications. The process of WTF resin for S/S process of heavy metal contaminated soils was studied. Laboratory-prepared slurries, made of field soils spiked with Cd 2+ and Cr 6+ were treated with WTF resin. The toxicity characteristic leaching procedure (TCLP) showed that with 2 wt% WTF, in the neutral condition of soil after treatment for 7 d, the leaching concentrations of Cd 2+ and Cr 6+ in contaminated soil were decreased by 80.3% and 92.6% respectively. Moreover, Tessier sequence extraction procedure showed WTF resin reduced the leaching concentration by transforming heavy metal from exchange form to organic form. The structure of WTF is obtained according to elemental analysis result and reaction mechanism. Through analysis of the infrared spectrogram of WTF and WTF heavy mental chelating precipitation, WTF can form stable chelate with heavy mental through coordination. The significant groups are hydroxyl, nitrogen and sulphur function groups in WTF mainly. Toxicology test revealed that the WTF resin is nontoxic to microorganism in the soils. Copyright © 2017 Elsevier B.V. All rights reserved.
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Feasibility analysis of EDXRF method to detect heavy metal pollution in ecological environment
NASA Astrophysics Data System (ADS)
Hao, Zhixu; Qin, Xulei
2018-02-01
The change of heavy metal content in water environment, soil and plant can reflect the change of heavy metal pollution in ecological environment, and it is important to monitor the trend of heavy metal pollution in eco-environment by using water environment, soil and heavy metal content in plant. However, the content of heavy metals in nature is very low, the background elements of water environment, soil and plant samples are complex, and there are many interfering factors in the EDXRF system that will affect the spectral analysis results and reduce the detection accuracy. Through the contrastive analysis of several heavy metal elements detection methods, it is concluded that the EDXRF method is superior to other chemical methods in testing accuracy and method feasibility when the heavy metal pollution in soil is tested in ecological environment.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarma, Debajit; Islam, Saiful M.; Subrahmanyam, K. S.
Heavy metal ions (Cd 2+, Hg 2+, As 3+ and Pb 2+) are an important contributor to the contamination of groundwater and other water bodies in and around industrial areas. Herein, we demonstrate the rapid and efficient capacity of a layered metal sulfide material, K2xSn4-xS8-x (x = 0.65-1, KTS-3) for heavy metal ion removal from water. The effect of concentration, pH, kinetics, and competitive ions such as Na +/Ca 2+ on the heavy metal ion removal capacity of KTS-3 was systematically investigated. X-ray photoelectron spectroscopy (XPS), elemental analyses, and powder X-ray diffraction studies revealed that the heavy metal ion-exchange ofmore » KTS-3 is complete (quantitative replacement of all potassium ions) and topotactic. The heavy metal ion-exchange by using KTS-3 follows the Langmuir-Freundlich model with high exchange capacities, q(m) 205(17) mg g -1 for Cd 2+, 372(21) mg g -1 for Hg 2+ and 391(89) mg g -1 for Pb 2+. KTS-3 retains excellent heavy metal ion-exchange capacity even in very high concentration (1 M) of competing ions (Na +/Ca 2+) and also over a broad pH range (2-12). KTS-3 also exhibits very good ion-exchange capacity for precious Ag + and toxic As 3+ ions. The kinetics of heavy metal ion adsorption by KTS-3 are rapid (absorbs all ions within a few minutes). These properties and the environmentally friendly character of KTS-3 make it a promising candidate for sequestration of heavy metal ions from water.« less
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Suman; Kardam, Abhishek; Gera, Meeta; Jain, V K
2015-01-01
The present work proposed a nanocellulose (NC)-silver nanoparticles (AgNPs) embedded pebbles-based composite material as a novel reusable cost-effective water purification device for complete removal of dyes, heavy metals and microbes. NC was prepared using acid hydrolysis of cellulose. The AgNPs were generated in situ using glucose and embedded within the porous concrete pebbles by the technique of inter-diffusion of ion, providing a very strong binding of nanoparticles within the porous pebbles and thus preventing any nanomaterials leaching. Fabrication of a continual running water purifier was achieved by making different layering of NC and Ag nano-embedded pebbles in a glass column. The water purifier exhibited not only excellent dye and heavy metal adsorption capacity, but also long-term antibacterial activity against pathogenic and non-pathogenic bacterial strains. The adsorption mainly occurred through electrostatic interaction and pore diffusion also contributed to the process. The bed column purifier has shown 99.48% Pb(II) and 98.30% Cr(III) removal efficiency along with 99% decontamination of microbial load at an optimum working pH of 6.0. The high adsorption capacity and reusability, with complete removal of dyes, heavy metals and Escherichia coli from the simulated contaminated water of composite material, will provide new opportunities to develop a cost-effective and eco-friendly water purifier for commercial application.
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Sounthararajah, Danious P.; Loganathan, Paripurnanda; Kandasamy, Jaya; Vigneswaran, Saravanamuthu
2015-01-01
Heavy metals constitute some of the most dangerous pollutants of water, as they are toxic to humans, animals, and aquatic organisms. These metals are considered to be of major public health concern and, therefore, need to be removed. Adsorption is a common physico-chemical process used to remove heavy metals. Dissolved organic carbon (DOC) and suspended solids (SS) are associated pollutants in water systems that can interact with heavy metals during the treatment process. The interactions of DOC and SS during the removal of heavy metals by granular activated carbon were investigated in batch and fixed-bed column experiments. Batch adsorption studies indicated that Langmuir adsorption maxima for Pb, Cu, Zn, Cd, and Ni at pH 6.5 were 11.9, 11.8, 3.3, 2.0, and 1.8 mg/g, respectively. With the addition of humic acid (HA) (DOC representative), they were 7.5, 3.7, 3.2, 1.6, and 2.5 mg/g, respectively. In the column experiment, no breakthrough (complete removal) was obtained for Pb and Cu, but adding HA provided a breakthrough in removing these metals. For Zn, Cd and Ni, this breakthrough occurred even without HA being added. Adding kaolinite (representative of SS) had no effect on Pb and Cu, but it did on the other metals. PMID:26343692
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Jian, Min-Fei; Li, Ling-Yu; Xu, Peng-Fei; Chen, Pu-Qing; Xiong, Jian-Qiu; Zhou, Xue-Ling
2014-05-01
Overlying water, sediments, surface soils in the typical wetland areas of Lean River and Poyang Lake which were rich in non-ferrous metal mineral resources on both sides of the river, were chosen for monitoring heavy metals including copper, lead and cadmium of base flow in average season, flood season, and dry season in 2012. Statistical analysis methods were coupled to characterize the spatiotemporal variation of heavy metals pollution and identify the main sources. The results indicated that the concentrations of copper were the highest in all samples of each sampling sites in the Lean River-Poyang Lake wetland. And the content values of copper, lead and cadmium in different samples of different sampling sites also showed that the content values of copper were higher than those of lead, and the content values of lead were also higher than those of cadmium. The results also showed that the heavy metals pollution of copper, lead and cadmium in flood season was the heaviest whereas the heavy metals pollution in dry season was comparatively light. The results of the contents of the three kinds of heavy metals elements in different sampling sites of the watersheds of lean River showed that the contents of copper in the samples from the upstream sampling sites of Lean River were higher than those of other samples from other sites. And the contents of lead in the samples from the downstream sampling sites of Lean River were higher than those of other samples from other sampling sites. The contents of cadmium in the samples from the midstream sampling sites of Lean River were higher than those of other samples from other sites. The first principal component representing copper pollution explained 36. 99% of the total variance of water quality. The second principal component concerning representing lead pollution explained 30. 12% of the total variance. The correlation analysis results showed that there were significant positive correlations among the contents of copper
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Ulmann, Vit; Kracalikova, Anna; Dziedzinska, Radka
2015-03-04
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.
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NASA Astrophysics Data System (ADS)
Pranoto; Inayati; Firmansyah, Fathoni
2018-04-01
Water is a natural resource that is essential for all living creatures. In addition, water also caused of disease affecting humans. The existence of one of heavy metal pollutants cadmium (Cd) in the body of water is an environmental problem having a negative impact on the quality of water resources. Adsorption is one of the ways or methods that are often used for the treatment of wastewater. Clay and allophanic soil were used as Cd adsorbent by batch method. Ceramic filter was used to reduce Cd concentration in the ground water. This study aims to determine the effect of the composition of clay and Allophane, activation temperature and contact time on the adsorption capacity of Cd in the model solution. The optimum adsorption condition and the effectiveness of drinking water treatment in accordance with Regulation of the Minister of Health using clay/Andisol adsorbents in ensnare heavy metals Cd and bacterial pathogens. Identification and characterization of adsorbent is done by using NaF, Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), specific surface area and total acidity specific. The Cd metal concentrations were analysed by atomic absorption spectroscopy. Adsorption isotherms determined by Freundlich and Langmuir equations. Modified water purification technology using ceramic filters are made with a mixture of clay and Andisol composition. The results showed samples of clay and Andisol containing minerals. The optimum condition of adsorption was achieved at 200 °C of activation temperature, 60 minutes of contact time and the 60:40 of clay:Andisol adsorbent composition. Freundlich isotherm represented Cd adsorption on the clay/Andisol adsorbent with a coefficient of determination (R2=0.99) and constant (k=1.59), higher than Langmuir (R2=0.89). The measurement results show the water purification technology using ceramic filters effectively reduce E. coli bacterial and Cd content in the water.
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Patel, Priyanka; Raju, N Janardhana; Reddy, B C Sundara Raja; Suresh, U; Sankar, D B; Reddy, T V K
2018-04-01
The concentration of heavy metals was analyzed each of 20 river water, suspended sediments and bed sediments along the stretch of Swarnamukhi River Basin. River water is not contaminated with heavy metals except Fe and Mn. Contamination factor in sediments shows considerable to very high degree contamination with Cr, Cu, Pb and Zn. The sources of these metals could be residential wastes, sewer outfall, fertilizers, pesticides (M-45 + carbondine) and traffic activities apart from natural weathering of granitic rocks present in the basin area. Principal component analyses indicate the interaction between metals in different media. The comparison of metals (Cu, Pb and Zn) in bed sediments of Swarnamukhi River with the Indian and world averages indicates that the values obtained in the basin are above the Indian averages and far below to the world averages. Average shale values and sediment quality guidelines point toward the enrichment and contamination of Cu, Cr, Pb and Zn to several fold leading to eco-toxicological risks in basin.
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Changes in water consumption linked to heavy news media coverage of extreme climatic events.
Quesnel, Kimberly J; Ajami, Newsha K
2017-10-01
Public awareness of water- and drought-related issues is an important yet relatively unexplored component of water use behavior. To examine this relationship, we first quantified news media coverage of drought in California from 2005 to 2015, a period with two distinct droughts; the later drought received unprecedentedly high media coverage, whereas the earlier drought did not, as the United States was experiencing an economic downturn coinciding with a historic presidential election. Comparing this coverage to Google search frequency confirmed that public attention followed news media trends. We then modeled single-family residential water consumption in 20 service areas in the San Francisco Bay Area during the same period using geospatially explicit data and including news media coverage as a covariate. Model outputs revealed the factors affecting water use for populations of varying demographics. Importantly, the models estimated that an increase of 100 drought-related articles in a bimonthly period was associated with an 11 to 18% reduction in water use. Then, we evaluated high-resolution water consumption data from smart meters, known as advanced metering infrastructure, in one of the previously modeled service areas to evaluate breakpoints in water use trends. Results demonstrated that whereas nonresidential commercial irrigation customers responded to changes in climate, single-family residential customers decreased water use at the fastest rate following heavy drought-related news media coverage. These results highlight the need for water resource planners and decision makers to further consider the importance of effective, internally and externally driven, public awareness and education in water demand behavior and management.
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Changes in water consumption linked to heavy news media coverage of extreme climatic events
Quesnel, Kimberly J.; Ajami, Newsha K.
2017-01-01
Public awareness of water- and drought-related issues is an important yet relatively unexplored component of water use behavior. To examine this relationship, we first quantified news media coverage of drought in California from 2005 to 2015, a period with two distinct droughts; the later drought received unprecedentedly high media coverage, whereas the earlier drought did not, as the United States was experiencing an economic downturn coinciding with a historic presidential election. Comparing this coverage to Google search frequency confirmed that public attention followed news media trends. We then modeled single-family residential water consumption in 20 service areas in the San Francisco Bay Area during the same period using geospatially explicit data and including news media coverage as a covariate. Model outputs revealed the factors affecting water use for populations of varying demographics. Importantly, the models estimated that an increase of 100 drought-related articles in a bimonthly period was associated with an 11 to 18% reduction in water use. Then, we evaluated high-resolution water consumption data from smart meters, known as advanced metering infrastructure, in one of the previously modeled service areas to evaluate breakpoints in water use trends. Results demonstrated that whereas nonresidential commercial irrigation customers responded to changes in climate, single-family residential customers decreased water use at the fastest rate following heavy drought-related news media coverage. These results highlight the need for water resource planners and decision makers to further consider the importance of effective, internally and externally driven, public awareness and education in water demand behavior and management. PMID:29075664
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NASA Astrophysics Data System (ADS)
Zarazua, G.; Ávila-Pérez, P.; Tejeda, S.; Barcelo-Quintal, I.; Martínez, T.
2006-11-01
The present area of study is located in the Upper Course of the Lerma River (UCLR). The Lerma is one of the most important rivers of Mexico, where it drains highly populated and industrialized regions. The aim of the present study is to determine the heavy metal concentration of Cr, Mn, Fe, Cu and Pb in dissolved and total phases of the UCLR by means of Total Reflection X-ray Fluorescence Spectrometry (TXRF). The surface water samples were collected at 8 sites distributed following the stream flow direction of the river. Four sampling campaigns were carried out in each site in a 1-year period. A sample preparation method was applied in order to obtain the total and dissolved fraction and to destroy the organic matter. The total heavy metal average concentration decrease in the following order: Fe (2566 μg/L) > Mn (300 μg/L) > Cu (66 μg/L) > Cr (21 μg/L) > Pb (15 μg/L). In general, the heavy metal concentrations in water of the UCLR are below the maximum permissible limits.
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Modeling of Heavy Metal Transformation in Soil Ecosystem
NASA Astrophysics Data System (ADS)
Kalinichenko, Kira; Nikovskaya, Galina N.
2017-04-01
The intensification of industrial activity leads to an increase in heavy metals pollution of soils. In our opinion, sludge from biological treatment of municipal waste water, stabilized under aerobic-anaerobic conditions (commonly known as biosolid), may be considered as concentrate of natural soil. In their chemical, physical and chemical and biological properties these systems are similar gel-like nanocomposites. These contain microorganisms, humic substances, clay, clusters of nanoparticles of heavy metal compounds, and so on involved into heteropolysaccharides matrix. It is known that microorganisms play an important role in the transformation of different nature substances in soil and its health maintenance. The regularities of transformation of heavy metal compounds in soil ecosystem were studied at the model of biosolid. At biosolid swelling its structure changing (gel-sol transition, weakening of coagulation contacts between metal containing nanoparticles, microbial cells and metabolites, loosening and even destroying of the nanocomposite structure) can occur [1, 2]. The promotion of the sludge heterotrophic microbial activities leads to solubilization of heavy metal compounds in the system. The microbiological process can be realized in alcaligeneous or acidogeneous regimes in dependence on the type of carbon source and followed by the synthesis of metabolites with the properties of flocculants and heavy metals extragents [3]. In this case the heavy metals solubilization (bioleaching) in the form of nanoparticles of hydroxycarbonate complexes or water soluble complexes with oxycarbonic acids is observed. Under the action of biosolid microorganisms the heavy metals-oxycarbonic acids complexes can be transformed (catabolised) into nano-sizing heavy metals- hydroxycarbonates complexes. These ecologically friendly complexes and microbial heteropolysaccharides are able to interact with soil colloids, stay in the top soil profile, and improve soil structure due
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Ye, Chen; Li, Siyue; Zhang, Yulong; Zhang, Quanfa
2011-07-15
The water-level-fluctuation zone (WLFZ) between the elevations of 145-175 m in China's Three Gorges Reservoir has experienced a novel hydrological regime with half a year (May-September) exposed in summer and another half (October-April) submerged in winter. In September 2008 (before submergence) and June 2009 (after submergence), soil samples were collected in 12 sites in the WLFZ and heavy metals (Hg, As, Cr, Cd, Pb, Cu, Zn, Fe, and Mn) were determined. Enrichment factor (EF), factor analysis (FA), and factor analysis-multiple linear regression (FA-MLR) were employed for heavy metal pollution assessment, source identification, and source apportionment, respectively. Results demonstrate spatial variability in heavy metals before and after submergence and elements of As, Cd, Pb, Cu, and Zn are higher in the upper and low reaches. FA and FA-MLR reveal that As and Cd are the primary pollutants before submergence, and over 45% of As originates from domestic sewage and 59% of Cd from industrial wastes. After submergence, the major contaminants are Hg, Cd, and Pb, and traffic exhaust contributes approximately 81% to Hg and industrial effluent accounts about 36% and 73% for Cd and Pb, respectively. Our results suggest that increased shipping and industrial wastes have deposited large amounts of heavy metals which have been accumulated in the WLFZ during submergence period. Copyright © 2011 Elsevier B.V. All rights reserved.
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Adsorptive removal of five heavy metals from water using blast furnace slag and fly ash.
Nguyen, Thuy Chung; Loganathan, Paripurnanda; Nguyen, Tien Vinh; Kandasamy, Jaya; Naidu, Ravi; Vigneswaran, Saravanamuthu
2017-07-13
Heavy metals can be serious pollutants of natural water bodies causing health risks to humans and aquatic organisms. The purpose of this study was to investigate the removal of five heavy metals from water by adsorption onto an iron industry blast furnace slag waste (point of zero charge (PZC) pH 6.0; main constituents, Ca and Fe) and a coal industry fly ash waste (PZC 3.0; main constituents, Si and Al). Batch study revealed that rising pH increased the adsorption of all metals with an abrupt increase at pH 4.0-7.0. The Langmuir adsorption maximum for fly ash at pH 6.5 was 3.4-5.1 mg/g with the adsorption capacity for the metals being in the order Pb > Cu > Cd, Zn, Cr. The corresponding values for furnace slag were 4.3 to 5.2 mg/g, and the order of adsorption capacities was Pb, Cu, Cd > Cr > Zn. Fixed-bed column study on furnace slag/sand mixture (1:1 w/w) revealed that the adsorption capacities were generally less in the mixed metal system (1.1-2.1 mg/g) than in the single metal system (3.4-3.5 mg/g). The data for both systems fitted well to the Thomas model, with the adsorption capacity being the highest for Pb and Cu in the single metal system and Pb and Cd in the mixed metal system. Our study showed that fly ash and blast furnace slag are effective low-cost adsorbents for the simultaneous removal of Pb, Cu, Cd, Cr and Zn from water.
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Li, Juan; Xing, Xing; Li, Jiao; Shi, Mei; Lin, Aijun; Xu, Congbin; Zheng, Jianzhong; Li, Ronghua
2018-03-01
Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy metal removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m 2 /g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy metal removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II). Copyright © 2017 Elsevier Ltd. All rights reserved.
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Trace elements and heavy metals in mineral and bottled drinking waters on the Iranian market.
Hadiani, Mohammad Rasoul; Dezfooli-Manesh, Shirin; Shoeibi, Shahram; Ziarati, Parisa; Mousavi Khaneghah, Amin
2015-01-01
A survey of Iranian waters, sampled from 2010 to 2013, is presented. A total of 128 water samples from 42 different brands of bottled mineral and drinking water were collected and analysed for contamination levels of lead (Pb), cadmium (Cd), copper (Cu), arsenic (As) and mercury (Hg). Determinations were performed using a graphite furnace atomic absorption spectrophotometer for Pb, Cd and Cu, a hydride vapour generation as well as an Arsenator digital kit (Wagtech WTD, Tyne and Wear, UK) for As and a direct mercury analyser for Hg. Arsenic concentration in six bottled gaseous mineral samples was higher than the related limit. Regardless of these, mean concentrations of Pb, Cd, Cu, As and Hg in all types of water samples were 4.50 ± 0.49, 1.08 ± 0.09, 16.11 ± 2.77, 5.80 ± 1.63 and 0.52 ± 0.03 µg L⁻¹, respectively. Values obtained for analysed heavy metals in all samples were permissible according to the limits of national and international standards.
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Rahman, Mir Tamzid; Kameda, Tomohito; Kumagai, Shogo; Yoshioka, Toshiaki
2018-07-01
Nitrate-intercalated MgAl layered double hydroxide (LDH) was successfully delaminated in water by a facile and effective method upon reflux at 120 °C for 24 h followed by sonication at 40 °C for 5 h. This process is environmentally friendly since water is the only solvent used. The delaminated nanosheets were characterized by microscopic, spectroscopic, and particle size analyses. The delamination process successfully produced octahedron-shaped single-layer nanosheets 50-150 nm in size. X-ray photoelectron spectroscopy (XPS) data confirmed that the surface elements and their chemical status are consistent with the basic layer of MgAl LDH. The delaminated nanosheets displayed higher adsorption capacity for removing heavy metals from waste water than the original powdered LDH. After treating the waste water, a sharp and intense peak in the X-ray powder diffraction (XRD) pattern of the precipitate confirms the restacking of the LDH nanosheets. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Ning, Daliang; Huang, Yong; Pan, Ruisong; Wang, Fayuan; Wang, Hui
2014-07-01
To investigate the effect of the eco-remediation on nutrients and heavy metals in river water and sediment, a field study was carried out in a site of a 2-year eco-remediation mainly using planted floating bed system in an urban river in China. Before remediation, the tested properties of water and sediment in the will-be remediated area were not different from the control area, except higher concentrations of chemical oxygen demand (COD) and total nitrogen (TN) in the river water. After remediation, the remediation area showed effective removal of in-stream nutrients and elevation of dissolved oxygen and transparency. Compared to the control area, the remediation area had higher concentration of nitrate and lower concentrations of COD, ammonium, Mn and hexavalent Cr in the river water after a 2-year remediation. The remediation area also showed higher concentrations of organic carbon, TN, nitrate, sulfate, Fe, Cu, Pb and Zn in the sediment than in the control area. Accordingly, special attention should be paid to the ecological risk of heavy metals in sediments and plants in river eco-remediation projects especially in rivers polluted by heavy metals, although the metals were lower than the level of considerable ecological risk in this study. Copyright © 2014 Elsevier B.V. All rights reserved.
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Wang, Lei; Jin, Jian; Li, Xiao-dong; Chi, Yong; Yan, Jian-hua
2010-08-01
An alkalis assisted hydrothermal process was induced to stabilize heavy metals both from municipal solid waste or medical waste incinerator fly ash and waste water. The results showed that alkalis assisted hydrothermal process removed the heavy metals effectively from the waste water, and reduced leachability of fly ash after process. The heavy metal leachabilities of fly ash studied in this paper were Mn 17,300 microg/L,Ni 1650 microg/L, Cu 2560 microg/L, Zn 189,000 microg/L, Cd 1970 microg/L, Pb 1560 microg/L for medical waste incinerator fly ash; Mn 17.2 microg/L, Ni 8.32 microg/L, Cu 235.2 microg/L, Zn 668.3 microg/L, Cd 2.81 microg/L, Pb 7200 microg/L for municipal solid waste incinerator fly ash. After hydrothermal process with experimental condition [Na2CO3 dosage (5 g Na2CO3/50 g fly ash), reaction time = 10 h, L/S ratio = 10/1], the heavy metal removal efficiencies of medical waste incinerator fly ash were 86.2%-97.3%, and 94.7%-99.6% for municipal solid waste incinerator fly ash. The leachabilities of both two kinds of fly ash were lower than that of the Chinese national limit. The mechanism of heavy metal stabilization can be concluded to the chemisorption and physically encapsulation effects of aluminosilicates during its formation, crystallization and aging process, the high pH value has some contribution to the heavy metal removal and stabilization.
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Wang, Guoqiang; Hu, Xinqi; Zhu, Yi; Jiang, Hong; Wang, Hongqi
2018-06-21
Heavy metal contamination in sediments is progressively being recognized as a challenging problem in large parts of the developing world, particularly in Asian countries. A drinking water lake in Yunnan-Guizhou plateau, China named Hongfeng Lake was selected as the research target. Forty surface sediment samples and 4 sediment cores were collected to reveal the accumulation of heavy metals in the sediments of the lake. The mean concentrations of Cr, Cu, Pb, Cd, As, and Hg in surface sediments were 81.67, 45.61, 29.78, 0.53, 22.71, and 0.25 mg/kg, respectively, which exceeded the background levels of sediment 1.1~3.3 times. The calculation of geoaccumulation (I geo ) and potential ecological risk (PER) index analysis were preformed, and the results showed a considerable risk for Cd and Hg on the whole. Spatially, the northern part showed a higher risk than the southern part and tributaries of the lake, and a moderate risk in the overall sediment of the lake. The historical level of heavy metals in Hongfeng Lake was traced by vertical sediments study and it was dated back approximately 35 years. The EF trends of a feature sampling site HF8 showed strong temporal variations, and peaked in the year 1995. After that, the EFs exhibited a declining trend, which reflects productive environmental protection and management by the local government. For the Hongfeng Lake, a typical lake with heavy metal-contaminated sediments, the in-situ remediation technique could be a suitable method for its remediation.
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N.P. Havill; J. Elkinton; J.C. Andersen; S.B. Hagen; Hannah J. Broadley; G.J. Boettner; A. Caccone
2017-01-01
The European winter moth, Operophtera brumata, is a non-native pest in the Northeastern USA causing defoliation of forest trees and crops such as apples and blueberries. This species is known to hybridize with O. bruceata, the Bruce spanworm, a native species across North America, although it is not known if there are hybrid...
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Heavy rainfall events and diarrhea incidence: the role of social and environmental factors.
Carlton, Elizabeth J; Eisenberg, Joseph N S; Goldstick, Jason; Cevallos, William; Trostle, James; Levy, Karen
2014-02-01
The impact of heavy rainfall events on waterborne diarrheal diseases is uncertain. We conducted weekly, active surveillance for diarrhea in 19 villages in Ecuador from February 2004 to April 2007 in order to evaluate whether biophysical and social factors modify vulnerability to heavy rainfall events. A heavy rainfall event was defined as 24-hour rainfall exceeding the 90th percentile value (56 mm) in a given 7-day period within the study period. Mixed-effects Poisson regression was used to test the hypothesis that rainfall in the prior 8 weeks, water and sanitation conditions, and social cohesion modified the relationship between heavy rainfall events and diarrhea incidence. Heavy rainfall events were associated with increased diarrhea incidence following dry periods (incidence rate ratio = 1.39, 95% confidence interval: 1.03, 1.87) and decreased diarrhea incidence following wet periods (incidence rate ratio = 0.74, 95% confidence interval: 0.59, 0.92). Drinking water treatment reduced the deleterious impacts of heavy rainfall events following dry periods. Sanitation, hygiene, and social cohesion did not modify the relationship between heavy rainfall events and diarrhea. Heavy rainfall events appear to affect diarrhea incidence through contamination of drinking water, and they present the greatest health risks following periods of low rainfall. Interventions designed to increase drinking water treatment may reduce climate vulnerability.
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A 12-Month Study of Food Crops Contaminated by Heavy Metals, Lusaka, Zambia
NASA Astrophysics Data System (ADS)
Holden, J. A.; Malamud, B. D.; Chishala, B. H.; Kapungwe, E.; Volk, J.; Harpp, K. S.
2009-04-01
We investigate heavy-metal contamination of irrigation water used for urban agriculture and subsequent contamination of food crops in Chunga, NW Lusaka, the capital of Zambia. Inhabitants of the Chunga area rely on urban agriculture as both a major source of income and food. From August 2004 to July 2005, monthly samples of irrigation water used and edible portions of food crops were taken from a farmer's plot at Chunga. The food crops (cabbage, Chinese cabbage, pumpkin leaves, rape, sweet potato leaves and tomatoes) are grown using irrigation throughout the year. Irrigation water samples and digested food crop samples were analysed using ICP-MS at the Department of Geology, Colgate University, USA for Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Ba, Hg, Tl, Pb, and U. We find heavy-metal concentrations present in both irrigation water and food crop samples. Zambian sample concentrations were compared to Zambian and international legislative and guideline limits for concentrations of heavy metals in industrial effluent, heavy metals in irrigation water and heavy metals in foods. In irrigation water samples recommended national and/or international legislative limits for Al, Cr, Mn, Fe, Cu, Hg, Pb and U were exceeded. Limits for Hg were exceeded by up to 130 times. There were heavy-metal concentrations above recommended limits in food crops for Cr, Fe, Ni, Cu, Zn, Cd, Hg and Pb throughout the different food crops grown and throughout the year. In all 14 samples recommended limits for Cr, Fe and Hg were exceeded. Zambian legislated limits for food crops were exceeded by up to 16 times for Pb and 58 times for Hg. The results of this study show that heavy metal contamination is present in irrigation water used and food crops grown in urban agriculture in Chunga, Lusaka, Zambia. Recommended maximum limits for heavy metals in irrigation water and food are exceeded in some samples indicating there may be a risk to health.
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Hadzi, George Yaw; Essumang, David Kofi; Ayoko, Godwin A
2018-06-16
Heavy metal contamination of selected rivers in Ghana was studied as part of a bigger project aimed at setting background standard for heavy metals in the Ghanaian environment. Water samples were collected from major mining and eight pristine areas. The samples were acid digested with aqua-regia and analyzed with ICP-MS for As, Cd, Hg, Zn, Cu, Mn, Fe, Cr, Al, V, Co, Ni, and Pb. The average concentrations (mg/L) from the pristine sites ranged from 0.002 ± 0.00(As) to 0.929 ± 0.06 (Fe) and 0.002 ± 0.00 (Pb) to 20.355 ± 5.60 (Fe) from the mining sites. With the exception of Al, Fe, and Mn, the metals level were found to be within the WHO and USEPA guideline limits. Hazard quotients (HQ) for ingestion and dermal contact for pristine and mining samples ranged from 3.00E-04 (Cu) to 0.84 (Cr) and 2.40E-06 (Cu) to 7.44 (As), respectively. The carcinogenic risk (CR) for ingestion and dermal contact ranged from 5.03E-06 to 1.71E-07 (Cr) and 4.22E-08 to 1.44E-09 (Cr), respectively. Arsenic showed a CR value higher than the acceptable limit (1.8E-02) from the mining sites which poses carcinogenic health threat. Multicriteria ranking suggests Birim river (EAM) as the most contaminated. The pattern recognition and multicriteria approach in characterizing the heavy metal contamination (for the first time in the case of Ghana) from the various sites will provide fresh insights into the risk assessment of heavy metals in contaminated surface waters.
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NASA Astrophysics Data System (ADS)
Yussuf, N. M.; Embong, Z.; Abdullah, S.; Masirin, M. I. M.; Tajudin, S. A. A.; Ahmad, S.; Sahari, S. K.; Anuar, A. A.; Maxwell, O.
2018-01-01
The heavy metal removal enhancement from polluted river water was investigated using two types of electrodes consist of integrated carbon-aluminium and a conventional aluminium plate electrode at laboratory-scale experiments. In the integrated electrode systems, the aluminium electrode surface was coated with carbon using mixed slurry containing carbon black, polyvinyl acetate and methanol. The electrochemical treatment was conducted on the parameter condition of 90V applied voltage, 3cm of electrode distance and 60 minutes of electrolysis operational time. Surface of both electrodes was investigated for pre and post electrolysis treatment by using SEM-EDX analytical technique. Comparison between both of the electrode configuration exhibits that more metals were accumulated on carbon integrated electrode surfaces for both anode and cathode, and more heavy metals were detected on the cathode. The atomic percentage of metals distributed on the cathode conventional electrode surface consist of Al (94.62%), Zn (1.19%), Mn (0.73%), Fe (2.81%) and Cu (0.64%), while on the anode contained O (12.08%), Al (87.63%) and Zn (0.29%). Meanwhile, cathode surface of integrated electrode was accumulated with more metals; O (75.40%), Al (21.06%), Zn (0.45%), Mn (0.22), Fe (0.29%), Cu (0.84%), Pb (0.47%), Na (0.94%), Cr (0.08%), Ni (0.02%) and Ag (0.22%), while on anode contain Al (3.48%), Fe (0.49 %), C (95.77%), and Pb (0.26%). According to this experiment, it was found that integrated carbon-aluminium electrodes have a great potential to accumulate more heavy metal species from polluted water compare to the conventional aluminium electrode. Here, heavy metal accumulation process obviously very significant on the cathode surface.
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Investigation of Single versus Dual - Hot and Cold Building Water Systems.
1981-10-15
S. Ramsey 2, Philip B. Shepherd JOHNS - MANVILLE SALES CORPORATION RESEARCH AND DEVELOPMENT CENTER KEN-CARYL RANCH DENVER, COLORADO 80217 15 October...Bruce DAAK 70-78-D-0002 Mark S. Ramsey Philip B. Shepherd 9PERFORMAING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMEN4T. PROJECT, TASK Johns - Manville Sales...0c NUMBER OF PIPE CCOLDOWN CYCLES FER DAY= 1.20 126 12/09/FC PAGE JOhNS - MANVILLE RESEARCH F DEVFLOPPENT CENTER ktlILDINC- HEATED WATER SUPPLY SYSTFM
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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
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Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide.
Singh, Neetesh; Casas-Bedoya, Alvaro; Hudson, Darren D; Read, Andrew; Mägi, Eric; Eggleton, Benjamin J
2016-12-15
We demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-IR absorption spectroscopy. This device can be used for gas and liquid sensing, especially to detect chemically similar molecules and precisely characterize extremely absorptive liquids that are difficult to detect by conventional infrared transmission techniques. We reliably measure concentrations up to 0.25% of heavy water (D2O) in a D2O-H2O mixture at its maximum absorption band at around 4 μm. This complementary metal-oxide-semiconductor (CMOS) compatible SOS D2O sensor is promising for applications such as measuring body fat content or detection of coolant leakage in nuclear reactors.
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The Bruce Report and social welfare leadership in the politics of Toronto’s “Slums”, 1934–1939.
George, Ryan
2011-01-01
Slum clearance and rebuilding first became a serious political project in Toronto during the 1930s. Following the release of a systematic housing survey known as the Bruce Report (1934), a set of actors distinguished by their planning authority with respect to social agencies, influence over social work education, coordination of social research, and role as spokespersons of religious bodies inaugurated a political struggle over state power. While the campaign failed, it called forth a reaction from established authorities and reconfigured the local political field as it related to low-income housing. This article gives an account of these processes by drawing upon correspondence and minutes of meetings of city officials and the campaign’s organizers, newspaper clippings, and published materials.
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Characterisation of heavy metal discharge into the Ria of Huelva.
Sainz, A; Grande, J A; de la Torre, M L
2004-06-01
The Ria of Huelva estuary, in SW Spain, is known to be one of the most heavy metal contaminated estuaries in the world. River contribution to the estuary of dissolved Cu, Zn, Mn, Cr, Ni, Cd, and As were analysed for the period 1988-2001. The obtained mean values show that this contribution, both because of the magnitude of total metals (895.1 kg/h), composition, toxicity (8.7 kg/h of As+Cd+Pb) and persistence, is an incomparable case in heavy metal contamination of estuaries. The amount and typology of heavy metal discharge to the Ria of Huelva are related to freshwater flow (and, consequently, to rainfall); as a result, two different types of heavy metal discharge can be distinguished in the estuary: during low water (50% of the days), with only 19.3 kg/h of heavy metals, and during high water or flood (17% of the days), where daily maximum discharge of 72,475 kg of heavy metals were recorded, from which 1481 kg were of As, 470 kg of Pb, and 170 kg of Cd. In the most frequent situation (77% of the days), the Odiel River discharges from 90% to 100% of the freshwater received by the estuary. Despite this, the high concentration of heavy metals in the Tinto River water causes this river to discharge into the Ria of Huelva 12.5% of fluvial total dissolved metal load received by the estuary.
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Adsorption of heavy metal in freeway by asphalt block
NASA Astrophysics Data System (ADS)
Zheng, Chaocheng
2017-08-01
Heavy metals are toxic, persistent, and carcinogenic in freeway. Various techniques are available for the removal of heavy metals from waste water among soils during freeway including ion-exchange, membrane filtration, electrolysis, coagulation, flotation, and adsorption. Among them, bio-sorption processes are widely used for heavy metal and other pollutant removal due to its sustainable, rapid and economic. In this paper, heavy metal removal facilitated by adsorption in plants during freeway was illustrated to provide concise information on exploring the adsorption efficiency.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhattacharya, A.; Ray, S.; Rai, R.
1995-12-31
Crude oil treatment systems for heavy oil assume paramount importance due to the difficult nature of emulsions formed and presence of water in the form of small droplets. With the aging of heavy oil fields, operating under active water drive, water content in the emulsion produced increases substantially. This has a direct impact on heater-treater performance and treated crude quality. A typical problem is discussed in this paper where the gradual increase in emulsion production over a period of time in heavy oil belts of ONGC have affected the electrostatic heater-treater performance, treating light crude doped heavy crude, resulting inmore » increased BS&W (basic sediments and water) in the treated crude. Critical levels of water cut in both heavy and light crudes have been identified beyond which the existing emulsion treating system becomes ineffective. Analysis have also been carried out to identify optimum mixing proportion which result in the most effective demulsification.« less
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Magnetic chitosan nanocomposites: a useful recyclable tool for heavy metal ion removal.
Liu, Xiaowang; Hu, Qiyan; Fang, Zhen; Zhang, Xiaojun; Zhang, Beibei
2009-01-06
Magnetic chitosan nanocomposites have been synthesized on the basis of amine-functionalized magnetite nanoparticles. These nanocomposites can be removed conveniently from water with the help of an external magnet because of their exceptional properties. The nanocomposites were applied to remove heavy metal ions from water because chitosan that is inactive on the surface of the magnetic nanoparticles is coordinated with them. The interaction between chitosan and heavy metal ions is reversible, which means that those ions can be removed from chitosan in weak acidic deionized water with the assistance of ultrasound radiation. On the basis of the reasons referred to above, synthesized magnetic chitosan nanocomposites were used as a useful recyclable tool for heavy metal ion removal. This work provides a potential platform for developing a unique route for heavy metal ion removal from wastewater.
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Huynh, T T; Laidlaw, W S; Singh, B; Gregory, D; Baker, A J M
2008-12-01
Heavy metal concentrations and pH of pore-water in contaminated substrates are important factors in controlling metal uptake by plants. We investigated the effects of phytoextraction on these properties in the solution phase of biosolids and diluted biosolids in a 12-month phytoextraction column experiment. Phytoextraction using Salix and Populus spp. temporarily decreased pore-water pH of the substrates over the experimental period followed by a return to initial pH conditions. Salixxreichardtii and Populus balsamifera effectively extracted Ni, Zn and Cd and actively mobilized these metals from the solid to the solution phase. S.xreichardtii had the stronger effect on mobilization of metals due to its larger root system. Phytoextraction did not affect Cu in the solution phase of the biosolids. Heavy metals were leached down to lower depths of the columns during the phytoextraction process.
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[Characteristics of heavy metals enrichment in algae ano its application prospects].
Lu, Kaixing; Tang, Jian-jun; Jiang, De'an
2006-01-01
Using algae to bio-remedy heavy metals-contaminated waters has become an available and practical approach for environmental restoration. Because of its special cell wall structure, high capacity of heavy metal-enrichment, and easy to desorption, algae has been considered as an ideal biological adsorbent. This paper briefly introduced the structural and metabolic characteristics adapted for heavy metals enrichment of algae, including functional groups on cell wall, extracellular products, and intracellular heavy metals-chelating proteins, discussed the enrichment capability of living, dead and immobilized algae as well as the simple and convenient ways for desorption, and analyzed the advantages and disadvantages of using algae for bioremediation of polluted water, and its application prospects.
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Ning, Yu; Li, Jihui; Cai, Wensheng; Shao, Xueguang
2012-10-01
A method for simultaneous determination of metal ions in river water was developed by using preconcentration and near-infrared diffuse reflectance spectroscopy (NIRDRS). An inorganic biomaterial, nano-hydroxyapatite (HAP) was used as a high-efficient adsorbent for gathering the ions from water samples. After adsorbing the analytes onto the adsorbent, NIRDRS was measured and partial least squares (PLS) models were established for fast and simultaneous quantitative prediction. With the samples prepared by river water, determination of Pb(2+), Zn(2+), Cu(2+), Cd(2+) and Cr(3+) was investigated. The calibration models of Cu(2+), Cr(3+) and total content were proven to be efficient enough for precise prediction. The determination coefficients (R(2)) of the independent validation were found as high as 0.9924, 0.9869 and 0.9273 for Cu(2+), Cr(3+) and total content, respectively. Therefore, the feasibility of NIRDRS for microanalysis of heavy metal ions in waste water was demonstrated. Copyright © 2012 Elsevier B.V. All rights reserved.
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Analysis of heavy metal accumulation in fish from the coastal waters of Terengganu, Malaysia
NASA Astrophysics Data System (ADS)
Rosli, M. N. R.; Samat, S. B.; Yasir, M. S.
2018-04-01
Bioaccumulation of toxic metals in fish causes serious threats to the human when they are consumed. Thus, the detection of toxic element concentration levels in fish is important. The accumulation of four heavy metal concentration of Cd, Cu, Mn and Zn in fish was determined. Five fish species namely Epinephelus lanceolatus, Rastrelliger, Megalaspis cordyla, Bramidae and Siganus canaliculatus were collected from the coastal waters of Terengganu, Malaysia. The analysis was done using inductive coupled plasma-mass spectrometer (ICP-MS) technique. The accumulation of the four heavy metals in muscle tissues of the fish are lower compared to liver and gill tissues. Cd concentration was higher in liver tissues except in Megalaspis cordyla. Meanwhile Cu concentration was higher in liver for all selected fishes. Mn concentration was higher in gill tissues of all fish studied while Zn concentration was higher in gill tissues except in Epinephelus lanceolatus and Rastrelliger. The highest average level of heavy metal recorded in fish is Zn (11.05 × 10-2 ± 1.44 × 10-2 mg kg-1) followed by Mn (1.81 × 10-2 ± 0.58 × 10-2 mg kg-1), Cu (0.70 × 10-2 ± 0.10 × 10-2 mg kg-1) and Cd (0.52×10-2 ± 0.27 × 10-2 mg kg-1). The metal concentration found in this study was lower than the national and international Recommended Dietary Allowance (RDA) for human consumption. Long term monitoring system of metal bioaccumulation in fishes need to be done to provide useful information for the assessment of the potential health risks of metals in Malaysia.
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Instruments to reduce the leaching of heavy metals from building materials in the Netherlands.
van Breemen, A J H; Vermij, P H M
2007-01-01
In the Netherlands the leaching of heavy metals from metal building and constructing materials results in serious contamination problems in the water system. The most common sources of these heavy metals in construction materials are copper waterworks and roofs, zinc roofs, gutters and rain pipes, zinced steel, stainless steel, and lead sealing material. In urban waters the surface water and sediment standards are often exceeded. Although building and construction materials are certainly not the only source of heavy metals, they are an important part of the problem. This article focuses on six instruments that are in use in the Netherlands to try to reduce impact on the surface waters. In addition to this, national as well as international, a reconsideration of the risks and surface water standards for several heavy metals is considered. A balanced use of instruments can be considered as the application of a best practice.
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NASA Astrophysics Data System (ADS)
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.
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Plant rhamnogalacturonan II complexation of heavy metal cations
O`Neill, M.A.; Pellerin, P.J.M.; Warrenfeltz, D.; Vidal, S.; Darvill, A.G.; Albersheim, P.
1999-03-02
The present invention provides rhamnogalacturonan-II (RG-II) and relates to its ability to complex specific multivalent heavy metal cations. In the presence of boric acid, RG-II monomers form dimers that are cross-linked by a borate ester. The yield of such borate ester cross-linked dimers of RG-II is enhanced in the presence of specific heavy metal cations. The present invention further relates to the utility of RG-II in assays for the detection of specific heavy metal contamination; as a reagent useful in the removal of specific heavy metal cations contaminating foods and liquids, for example, fish, wines, etc.; as a pharmaceutical composition useful as an antidote in specific heavy metal cation poisoning; as a treatment for the detoxification of specific heavy metal cations from blood and/or tissues; and in a method of remediation of waters and soils contaminated with specific heavy metal cations. 15 figs.
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Plant rhamnogalacturonan II complexation of heavy metal cations
O'Neill, Malcolm A.; Pellerin, Patrice J. M.; Warrenfeltz, Dennis; Vidal, Stephane; Darvill, Alan G.; Albersheim, Peter
1999-01-01
The present invention provides rhamnogalacturonan-II (RG-II) and relates to its ability to complex specific multivalent heavy metal cations. In the presence of boric acid, RG-II monomers form dimers that are cross-linked by a borate ester. The yield of such borate ester cross-linked dimers of RG-II is enhanced in the presence of specific heavy metal cations. The present invention further relates to the utility of RG-II in assays for the detection of specific heavy metal contamination; as a reagent useful in the removal of specific heavy metal cations contaminating foods and liquids, for example, fish, wines, etc.; as a pharmaceutical composition useful as an antidote in specific heavy metal cation poisoning; as a treatment for the detoxification of specific heavy metal cations from blood and/or tissues; and in a method of remediation of waters and soils contaminated with specific heavy metal cations.
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Microbes in Heavy Metal Remediation: A Review on Current Trends and Patents.
Mishra, Geetesh Kumar
2017-01-01
Heavy metal pollution in the environmental samples like soil, water and runoff water is a worldwide problem. Such contamination of environmental matrices by the heavy metals accumulates due to various activities involving human driven sources and industries, although agriculture and sewage disposal are the largest source for the heavy metal contamination. Disposal of heavy metals or waste products containing heavy metals in the environment postures a trivial threat to public safety and health. Heavy metals are persistence and they can also cause biomagnifications and accumulate in food chain. Microbial bioremediation of heavy metal is emerging as an effective technique. Microbial bioremediation is a highly efficient environmental friendly procedure which also reduces the cost of cleanup process associated with heavy metal contamination. New methods for removal of heavy metals from the environmental samples are under development and most recent advancements have been made in exploring the knowledge of metal-microbes interactions and its use for heavy metal remediation. This review paper will focus on the microbial bioremediation process and highlight some of the newly developed patented methods for microbial bioremediation of the heavy metals from the environmental samples using microbial populations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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NASA Astrophysics Data System (ADS)
Haria, A. H.; Johnson, A. C.; Bell, J. P.; Batchelor, C. H.
1994-12-01
The processes and mechanisms that control pesticide transport from drained heavy clay catchments are being studied at Wytham Farm (Oxford University) in southern England. In the first field season field-drain water contained high concentrations of pesticide. Soil studies demonstrated that the main mechanism for pesticide translocation was by preferential flow processes, both over the soil surface and through the soil profile via a macropore system that effectively by-passed the soil matrix. This macropore system included worm holes, shrinkage cracks and cracks resulting from ploughing. Rainfall events in early winter rapidly created a layer of saturation in the A horizon perched above a B horizon of very low hydraulic conductivity. Drain flow was initiated when the saturated layer in the A horizon extended into the upper 0.06m of the soil profile; thereafter water moved down slope via horizontal macropores possibly through a band of incorporated straw residues. These horizontal pathways for water movement connected with the fracture system of the mole drains, thus feeding the drains. Overland flow occurred infrequently during the season.
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Wang, Chunfeng; Zhu, Nengmin; Wang, Yanmin; Zhang, Fushen
2012-01-17
The simultaneous detoxification processes of transformer oil-contained PCBs and heavy metals in medical waste incinerator (MWI) fly ash were developed under sub- and supercritical water. The addition of MWI fly ash to transformer oil-contained PCBs was found to increase the destruction efficiency of PCBs, at the same time, it facilitated reducing the leaching concentration of toxic metals from residues (obtained after reaction) for harmless disposal. In this study, we elucidated primarily the catalysis possibility of heavy metals in raw MWI fly ash for PCBs degradation by adopting the sequential extraction procedure. For both MWI fly ashes, more than 90% destruction efficiency of PCBs was achieved at ≥375 °C for 30 min, and trichlorobenzene (TCB) existing in the transformer oil was also completely decomposed. The correlation of catalytic performance to PCBs degradation was discussed based on structural characteristics and dechlorinated products. Likewise, such process rendered residues innocuous through supercritical water treatment for reuse or disposal in landfill.
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NASA Astrophysics Data System (ADS)
Kiikkilä, O.; Nieminen, T.; Starr, M.; Ukonmaanaho, L.
2012-04-01
Boreal peatlands form an important terrestrial carbon reserve and are a major source of dissolved organic matter (DOM) to surface waters, particularly when disturbed through forestry practices such as draining or timber harvesting. Heavy metals show a strong affinity to organic matter and so, along with DOM, heavy metals can be mobilized and transported from the soil to surface waters and sediments where they may become toxic to aquatic organisms and pass up the food chain. The complexation of heavy metals with DOM can be expected to be related and determined by the chemical characteristics of DOM and oxidation/reducing conditions in the peat. We extracted interstitial water from peat samples and determined the concentrations of dissolved organic carbon (DOC), dissolved organic nitrogen (DON) and Al, Cu, Zn and Fe in various fractions of DOM isolated by adsorption properties (XAD-8 fractionation) and molecular-weight (ultrafiltration). The peat samples were taken from 0-30 and 30-50 cm depth in drained peatland catchments two years after whole-tree or stem-only clear-cut harvesting (Scots pine or Norway spruce) had been carried out. The samples from the upper layer had been subject to alternating saturation/aeration conditions while the deeper layer had been continuously under the water table. The fractionation of DOC and DON according to both adsorption properties and molecular-weight fractions clearly differed between the upper and lower peat layers. While the hydrophobic acid fraction contained proportionally more DOC and DON than the hydrophilic acid fraction in the upper peat layer the results were vice versa in the lower peat layer. High-molecular-weight compounds (> 100 kDa) were proportionally more abundant in the upper and low-molecular-weight compounds (< 1 kDa) in the lower peat layer. These differences are assumed to reflect differences in the aerobic/ anaerobic conditions and degree of decomposition between the two layers. The concentrations of Zn, Al
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To study the recovery of L-Cysteine using halloysite nanotubes after heavy metal removal
NASA Astrophysics Data System (ADS)
Thakur, Juhi
2016-04-01
Industrial wastes are a major source of soil and water pollution that originate from mining industries, chemical industries, metal processing industries, etc. These wastes consist of a variety of chemicals including phenolics, heavy metals, etc. Use of industrial effluent and sewage sludge on agricultural land has become a common practice in the world which results in these toxic metals being transferred and ultimately concentrate in plant tissues from water and the soil. The metals that get accumulated, prove detrimental to plants themselves and may also cause damage to the healths of animals as well as man. This is because the heavy metals become toxins above certain concentrations, over a narrow range. As a further matter, these metals negatively affect the natural microbial populations as well, that leads to the disruption of fundamental ecological processes. However, many techniques and methods have been advanced to clear the heavy metal polluted soils and waters. One important method is by removing heavy metals with the help of amino acids like L-Cysteine and L-Penicillamine. But also, economy of removal of pollutant heavy metals from soils and waters is a major concern. Present study helps in decreasing the cost for large-scale removal of heavy metals from polluted water by recovering the amino acid (L-Cysteine) after removal of nickel (Ni+2) at a fixed pH, by binding the Ni+2 with halloysite nanotubes(HNT), so that L-Cysteine can be reused again for removal of heavy metals.
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ERIC Educational Resources Information Center
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.)
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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 Pb
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NASA Astrophysics Data System (ADS)
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
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Qu, Liyin; Huang, Hong; Xia, Fang; Liu, Yuanyuan; Dahlgren, Randy A; Zhang, Minghua; Mei, Kun
2018-06-01
Heavy metal pollution is a major concern in China because of its serious effects on human health. To assess potential human health and ecological risks of heavy metal pollution, concentration data for seven heavy metals (As, Pb, Cd, Cr, Hg, Cu, Zn) from 14 sites spanning the rural-urban interface of the Wen-Rui Tang River watershed in southeast China were collected from 2000 to 2010. The heavy metal pollution index (HPI), hazard index (HI) and carcinogenic risk (CR) metrics were used to assess potential heavy metal risks. Further, we evaluated the uncertainty associated with the risk assessment indices using Monte Carlo analysis. Results indicated that all HPI values were lower than the critical level of 100 suggesting that heavy metal levels posed acceptable ecological risks; however, one site having an industrial point-source input reached levels of 80-97 on several occasions. Heavy metal concentrations fluctuated over time, and the decrease after 2007 is due to increased wastewater collection. The HI suggested low non-carcinogenic risk throughout the study period (HI < 1); however, nine sites showed CR values above the acceptable level of 10 -4 for potential cancer risk from arsenic in the early 2000s. Uncertainty analysis revealed an exposure risk for As at all sites because some CR values exceeded the 10 -4 level of concern; levels of Cd near an old industrial area also exceeded the Cd exposure standard (2.6% of CR values > 10 -4 ). While most metrics for human health risk did not exceed critical values for heavy metals, there is still a potential human health risk from chronic exposure to low heavy metal concentrations due to long-term exposure and potential metal interactions. Results of this study inform water pollution remediation and management efforts designed to protect public health in polluted urban area waterways common in rapidly developing regions. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Remediation of biochar on heavy metal polluted soils
NASA Astrophysics Data System (ADS)
Wang, Shuguang; Xu, Yan; Norbu, Namkha; Wang, Zhan
2018-01-01
Unreasonable mining and smelting of mineral resources, solid waste disposal, sewage irrigation, utilization of pesticides and fertilizers would result in a large number of heavy metal pollutants into the water and soil environment, causing serious damage to public health and ecological safety. In recent years, a majority of scholars tried to use biochar to absorb heavy metal pollutants, which has some advantages of extensive raw material sources, low-cost and high environmental stability. This paper reviewed the definition, properties of biochar, the mechanism of heavy metal sorption by biochar and some related problems and prospects, to provide some technical support for the application of biochar into heavy metal polluted soils.
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Phytoremediation of Heavy Metals in Contaminated Water and Soil Using Miscanthus sp. Goedae-Uksae 1.
Bang, Jihye; Kamala-Kannan, Seralathan; Lee, Kui-Jae; Cho, Min; Kim, Chang-Hwan; Kim, Young-Jin; Bae, Jong-Hyang; Kim, Kyong-Ho; Myung, Hyun; Oh, Byung-Taek
2015-01-01
The aim of this study is to characterize the heavy metal phytoremediation potential of Miscanthus sp. Goedae-Uksae 1, a hybrid, perennial, bio-energy crop developed in South Korea. Six different metals (As, Cu, Pb, Ni, Cd, and Zn) were used for the study. The hybrid grass effectively absorbed all the metals from contaminated soil. The maximum removal was observed for As (97.7%), and minimum removal was observed for Zn (42.9%). Similarly, Goedae-Uksae 1 absorbed all the metals from contaminated water except As. Cd, Pb, and Zn were completely (100%) removed from contaminated water samples. Generally, the concentration of metals in roots was several folds higher than in shoots. Initial concentration of metals highly influenced the phytoremediation rate. The results of the bioconcentration factor, translocation factor, and enrichment coefficient tests indicate that Goedae-Uksae 1 could be used for phytoremediation in a marginally contaminated ecosystem.
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Gao, Bo; Li, Qiang; Zhou, Huai-Dong; Gao, Ji-Jun; Zou, Xiao-Wen; Yong, Huang
2014-05-01
The six heavy metal concentrations (Cr, Cr, As, Cd, Cu, Zn and Pb) in water samples collected from five reservoirs of Liao River Basin were studied. The health risk assessment for heavy metals pollution in reservoirs was conducted based on the environmental health risk assessment model recommended by U. S. Environmental Protection Agency. The results showed that the average concentrations of Cr, Cu, Zn, As, Cd and Pb in five reservoirs of Liao River Basin were 3.36, 1.03, 2. 70, 1.23, 0. 02 and 0. 03 microg L-1, respectively. In fact, these heavy metals concentrations were obviously lower than the Standard of National Drinking Water in China (GB 5749-2006). The results also showed that the metal carcinogenic risk was relatively high in this region. The order of the risk level of carcinogenic metals was Cr>As>Cd. The highest carcinogenic risk was from Cr, with the risk for adults ranging from 4. 50 X 10(-5) approximately 7. 53 X 10(-5) a-1' and the risk for children ranging from 6. 29 X 10(-5) to 1. 05 X 10(-4) a-1. The health risk levels caused by non-carcinogenic metals ranging from 10-13 to 10(-10) a-1 were lower than the acceptable range suggested by International Commission on Radiological Protection (ICRP) and the order of the risk level of non-carcinogenic metals was Cu>Zn>Pb. The total health risk of heavy metals for adults ranging from 1. 07X 10(-4) to 1. 72X 10(-4) a-1 and for children ranging from 1. 49 X 10(-4) to 2. 40 X 10(-4) a-1 exceeded the accepted level of 5 X 10(-5) a-1 as suggested by ICRP. The health risk levels of carcinogenic metals were significantly higher than those of non-carcinogenic metals in the reservoirs for Liao River Basin.
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Sounthararajah, D P; Loganathan, P; Kandasamy, J; Vigneswaran, S
2015-04-28
Heavy metals are serious pollutants in aquatic environments. A study was undertaken to remove Cu, Cd, Ni, Pb and Zn individually (single metal system) and together (mixed metals system) from water by adsorption onto a sodium titanate nanofibrous material. Langmuir adsorption capacities (mg/g) at 10(-3)M NaNO3 ionic strength in the single metal system were 60, 83, 115 and 149 for Ni, Zn, Cu, and Cd, respectively, at pH 6.5 and 250 for Pb at pH 4.0. In the mixed metals system they decreased at high metals concentrations. In column experiments with 4% titanate material and 96% granular activated carbon (w/w) mixture at pH 5.0, the metals breakthrough times and adsorption capacities (for both single and mixed metals systems) decreased in the order Pb>Cd, Cu>Zn>Ni within 266 bed volumes. The amounts adsorbed were up to 82 times higher depending on the metal in the granular activated carbon+titanate column than in the granular activated carbon column. The study showed that the titanate material has high potential for removing heavy metals from polluted water when used with granular activated carbon at a very low proportion in fixed-bed columns. Copyright © 2015 Elsevier B.V. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Chrones, J.
1951-05-29
A process which produces H/sub 2/ water enriched in D is described. Natural gas is oxidized to CO and H/sub 2/. These gases at 600 C reduce FeO in a fluidized bed regenerator, and the mixture of gases leaving the regenerator is burned in the boiler which supplies steam at 600 C. This steam reacts with iron dust from the regenerator to produce FeO and H/sub 2/ The deuterium is stripped from the H/sub 2/ with water in a catalytic exchange tower. The water thus enriched passes to an electrolytic step which concentrates D/sub 2/O to 99.8%. (T.R.H.)
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Bio-clarification of water from heavy metals and microbial effluence using fungal chitosan.
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.
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NASA Astrophysics Data System (ADS)
Pérez-Gimeno, Ana; Navarro-Pedreño, Jose; Gómez, Ignacio; Belén Almedro-Candel, María; Jordán, Manuel M.; Bech, Jaume
2015-04-01
The use of composted sewage sludge and limestone outcrop residue in soil restoration and technosol making can influence the mobility of heavy metals into groundwater. The use of compost from organic residues is a common practice in soil and land rehabilitation, technosol making, and quarry restoration (Jordán et al. 2008). Compost amendments may improve the physical, chemical, and biological properties of soils (Jordão et al. 2006; Iovieno et al. 2009). However, the use of compost and biosolids may have some negative effects on the environment (Karaca 2004; Navarro-Pedreño et al. 2004). This experiment analyzed the water pollution under an experimental design based on the use of columns (0-30 cm) formed by both wastes. Two waters of different quality (saline and non-saline) were used for irrigation. The presence of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the leachates was checked under controlled conditions inside a greenhouse (mean values: 20°±5°C and around 60% relative humidity). Sixteen 30-cm tall columns made of PVC pipe with internal diameters of 10.5 cm were prepared. The columns were filled with one of these materials: either sewage sludge compost (SW) or limestone outcrop residue (LR), fraction (<4 mm). The columns were irrigated with 2000 mL/week (230 mm) for twelve weeks (April to July). Half of them were irrigated with non-saline water (NS) and the others were so with saline water (S) from the beginning of the experiment. Four treatments combining the quality of the irrigation water (saline and non-saline) and wastes were studied: SW-NS, SW-S, LR-NS, and LR-S. After 24 hours of irrigation on the first day of each week, the leachates were taken and analyzed the heavy metal content (AAS-ES espectometer). The environmental risk due to the presence of heavy metals associated with the use of these materials was very low in general (under 0.1 mg/L). The use of sewage sludge favoured the presence of these metals in the lecheates and no effect
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Heavy metals pollution status in surface sediments (rivers and artifical lakes, Serbia)
NASA Astrophysics Data System (ADS)
Sakan, Sanja; Đorđević, Dragana
2017-04-01
Potentially hazardous trace elements, often in literature referred as "heavy metals", are deemed serious pollutants due to their toxicity, persistence and non-degradability in the environment. These elements play an important role in extent of water pollution and threaten the health of populations and ecosystems. As the sink of heavy metals, sediment beds adsorb metals in quantities that are many times higher than those found in the water column in the long-term polluted water environment. It is believed that most of the metal content, as much as 90% in aquatic sediments is bound to sediments. Metal contamination in these sediments could be directly affect the river water quality, resulting in potential consequences to the sensitive lowest levels of the food chain and ultimately to human health. The objective of this research was the evaluation of heavy metal contamination level in sediments of the most important rivers and artificial lakes in Serbia. The heavy metal enrichment in studied sediments was conducted by using: determination of total metal content, sequential extraction procedure for the fractionation of studied elements, quantification of the metal enrichment degree in the sediments by calculating geo-accumulation indices, determination of actual and potential element availability and application of BRAI index for the assessment of heavy metal bioavailability. The sediments were found to be contaminated by heavy metals to various extents, mostly with Cd, Cu, and Zn. The significant variation in heavy metal distribution among samples collected in this large region, encompassing all Serbian watersheds, suggests the selective contamination of sediments by heavy metals. Elevated concentrations of elements in most cases were detected in samples of river sediments, since artificial lake reservoirs are usually built in rural areas, where the less anthropogenic pollution. Rivers often flow through the towns and these water basins less or more loaded
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Identifying heavy metal levels in historical flood water deposits using sediment cores.
Lintern, Anna; Leahy, Paul J; Heijnis, Henk; Zawadzki, Atun; Gadd, Patricia; Jacobsen, Geraldine; Deletic, Ana; Mccarthy, David T
2016-11-15
When designing mitigation and restoration strategies for aquatic systems affected by heavy metal contamination, we must first understand the sources of these pollutants. In this study, we introduce a methodology that identifies the heavy metal levels in floodplain lake sediments deposited by one source; fluvial floods. This is done by comparing sediment core heavy metal profiles (i.e., historical pollution trends) to physical and chemical properties of sediments in these cores (i.e., historical flooding trends). This methodology is applied to Willsmere and Bolin Billabongs, two urban floodplain lakes (billabongs) of the Yarra River (South-East Australia). Both billabongs are periodically inundated by flooding of the Yarra River and one billabong (Willsmere Billabong) is connected to an urban stormwater drainage network. 1-2-m long sediment cores (containing sediment deposits up to 500 years old) were taken from the billabongs and analysed for heavy metal concentrations (arsenic, chromium, copper, lead, nickel, zinc). In cores from both billabongs, arsenic concentrations are high in the flood-borne sediments. In Bolin Billabong, absolute metal levels are similar in flood and non-flood deposits. In Willsmere Billabong, absolute copper, lead and zinc levels were generally lower in fluvial flood-borne sediments in the core compared to non-fluvial sediments. This suggests that heavy metal concentrations in Bolin Billabong sediments are relatively similar regardless of whether or not fluvial flooding is occurring. However for Willsmere Billabong, heavy metal concentrations are high when overland runoff, direct urban stormwater discharges or atmospheric deposition is occurring. As such, reducing the heavy metal concentrations in these transport pathways will be of great importance when trying to reduce heavy metal concentrations in Willsmere Billabong sediments. This study presents a proof-of-concept that can be applied to other polluted aquatic systems, to understand the
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Setyono, Daisy; Valiyaveettil, Suresh
2016-01-25
Paper, a readily available renewable resource, comprises of interwoven cellulosic fibers, which can be functionalized to develop interesting low-cost adsorbent material for water purification. In this study, polyethyleneimine (PEI)-functionalized paper was used for the removal of hazardous pollutants such as Au and Ag nanoparticles, Cr(VI) anions, Ni(2+), Cd(2+), and Cu(2+) cations from spiked water samples. Compared to untreated paper, the PEI-coated paper showed significant improvement in adsorption capacities toward the pollutants investigated in this study. Kinetics, isotherm models, pH, and desorption studies were carried out to study the adsorption mechanism of pollutants on the adsorbent surface. Adsorption of pollutants was better described by pseudo-second order kinetics and Langmuir isotherm model. Maximum adsorption of anionic pollutants was achieved at pH 5 while that of cations was at pH>6. Overall, the PEI-functionalized paper showed interesting Langmuir adsorption capacities for heavy metal ions such as Cr(VI) (68 mg/g), Ni(2+) (208 mg/g), Cd(2+) (370 mg/g), and Cu(2+) (435 mg/g) ions at neutral pH. In addition, the modified paper was also used to remove Ag-citrate (79 mg/g), Ag-PVP (46 mg/g), Au-citrate (30 mg/g), Au-PVP (17 mg/g) nanoparticles from water. Desorption of NPs from the adsorbent was done by washing with 2 M HCl or thiourea solution, while heavy metal ions were desorbed using 1 M NaOH or HNO3 solution. The modified paper retained its extraction efficiencies upon desorption of pollutants. Copyright © 2015 Elsevier B.V. All rights reserved.
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Further evaluations of the toxicity of irradiated advanced heavy water reactor fuels.
Edwards, Geoffrey W R; Priest, Nicholas D
2014-11-01
The neutron economy and online refueling capability of heavy water moderated reactors enable them to use many different fuel types, such as low enriched uranium, plutonium mixed with uranium, or plutonium and/or U mixed with thorium, in addition to their traditional natural uranium fuel. However, the toxicity and radiological protection methods for fuels other than natural uranium are not well established. A previous paper by the current authors compared the composition and toxicity of irradiated natural uranium to that of three potential advanced heavy water fuels not containing plutonium, and this work uses the same method to compare irradiated natural uranium to three other fuels that do contain plutonium in their initial composition. All three of the new fuels are assumed to incorporate plutonium isotopes characteristic of those that would be recovered from light water reactor fuel via reprocessing. The first fuel investigated is a homogeneous thorium-plutonium fuel designed for a once-through fuel cycle without reprocessing. The second fuel is a heterogeneous thorium-plutonium-U bundle, with graded enrichments of U in different parts of a single fuel assembly. This fuel is assumed to be part of a recycling scenario in which U from previously irradiated fuel is recovered. The third fuel is one in which plutonium and Am are mixed with natural uranium. Each of these fuels, because of the presence of plutonium in the initial composition, is determined to be considerably more radiotoxic than is standard natural uranium. Canadian nuclear safety regulations require that techniques be available for the measurement of 1 mSv of committed effective dose after exposure to irradiated fuel. For natural uranium fuel, the isotope Pu is a significant contributor to the committed effective dose after exposure, and thermal ionization mass spectrometry is sensitive enough that the amount of Pu excreted in urine is sufficient to estimate internal doses, from all isotopes, as low
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Yajima, Ichiro; Zou, Cunchao; Li, Xiang; Nakano, Chizuru; Omata, Yasuhiro; Kumasaka, Mayuko Y
2015-01-01
Heavy-metal pollution occurs in various environments, including water, air and soil, and has serious effects on human health. Since heavy-metal pollution in drinking water causes various diseases including skin cancer, it has become a global problem worldwide. However, there is limited information on the mechanism of development of heavy-metal-mediated disease. We performed both fieldwork and experimental studies to elucidate the levels of heavy-metal pollution and mechanisms of development of heavy-metal-related disease and to develop a novel remediation system. Our fieldwork in Bangladesh, Vietnam and Malaysia demonstrated that drinking well water in these countries was polluted with high concentrations of several heavy metals including arsenic, barium, iron and manganese. Our experimental studies based on the data from our fieldwork demonstrated that these heavy metals caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system with which toxic heavy metals were absorbed from polluted drinking water. Implementation of both fieldwork and experimental studies is important for prediction, prevention and therapy of heavy-metal-mediated diseases.
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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
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NASA Astrophysics Data System (ADS)
Chun Sang, H.
2016-12-01
n order to determine and prevent the number of ecological effects of heavy metals in the materials, we have to accurately measure the heavy metals present in the water-based protection ecosystems and may determine the effects to humans. Heavy metals occurred in the industrial effluent which is a state in which the monitor, based on the emission standards are made by the Ministry of Environment and managed and waste water contained Copper, Zinc, lead, etc. These heavy metals are able to express the toxic effects only when present in the free-ions in the aqueous condition, which appears differently affected by the degree to hardness change in accordance with the season, precipitation. Generally changing hardness concentration can not precisely evaluate toxic effects of heavy metals in the water system. Anderson announced a study on bioassay for heavy metals from industrial waste water using Daphnia magna(Anderson, 1944, 1948). Breukelman published study the resitivity difference for the mercury Chloride(HgCl2). Braudouin(1974) compared the zooplankton(Daphnia sp.) acute toxicity of the different heavy metals and confirmed the sensitivity. Shcherban(1979) presented for toxicity evaluation results for the heavy metal of the Daphnia magna according to different temperature conditions. In the United States Environmental Protection Agency(EPA) established a standard test method for water fleas, managed and supervised water ecosystems, and announced the adoption of a bioassay standard method. This study was performed to evaluate acute inhibition using the Daphnia magna for the biological effect of heavy metal ions in water-based toxicity in the hardness change. Evaluation methods were conducted in EPA Water Quality process test criteria. TU(Toxic Unit), NOEC (No Observable Effect Concentration), LOEC (Lowest Observable Effect Concentration), EC50 (Median Effective Concentration) was calculated by Toxcalc 5.0 Program. Keywords : D. magna, Hardness, Toxic Unit, Heavy metal
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Pyrolized biochar for heavy metal adsorption
Removal of copper and lead metal ions from water using pyrolized plant materials. Method can be used to develop a low cost point-of-use device for cleaning contaminated water. This dataset is associated with the following publication:DeMessie, B., E. Sahle-Demessie , and G. Sorial. Cleaning Water Contaminated With Heavy Metal Ions Using Pyrolyzed Banana Peel Adsorbents. Separation Science and Technology. Marcel Dekker Incorporated, New York, NY, USA, 50(16): 2448-2457, (2015).
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Sensitivity of midge larvae of Chironomus tentans Fabricius (Diptera Chironomidae) to heavy metals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khangarot, B.S.; Ray, P.K.
1989-03-01
The discharge of heavy metals into the natural waters has numerous obvious impacts on physical, chemical and biological parameters of aquatic ecosystem. Bioassay tests are important steps in establishing appropriate water quality criteria and standards for diverse use of ponds, lakes, streams and river waters. Therefore, the acute toxicities of various heavy metals to water flea Daphnia magna, and snail Lymnaea acuminata, and toad tadpoles Bufo mentanostictus have been reported from the authors' laboratory. Chironomid larvae might be particularly useful as indicators of water quality because they are widely distributed in freshwater systems and often from diverse communities within particularmore » habitat. The aim of this study was to determine the acute toxicity of ten heavy metals to the midge larvae Chironomus tentans Fabricius, which forms an important link in aquatic food chain(s).« less
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Heavy metal flows in aquatic systems of the Don and Kuban river deltas
NASA Astrophysics Data System (ADS)
Tkachenko, A. N.; Tkachenko, O. V.; Lychagin, M. Yu.; Kasimov, N. S.
2017-05-01
This paper presents the calculated heavy metal (Fe, Mn, Zn, Ni, Cu, Cr, Co, Cd, and Pb) flows in suspended and dissolved forms in the main navigable branches of the Don and Kuban river deltas during the low-water period of 2013-2014. This work is based on the data of field studies in which water and suspended matter samples were collected and the turbidity and water discharge in deltas were measured. A quantitative estimate of heavy metal inflows into the deltas of the Don and Kuban rivers is provided. Transformation of flows of suspended and dissolved metal forms from the delta top to the sea edge is discussed. The influence of localities (Rostov-on-Don, Temryuk) on the increase in heavy metal flows downstream is shown, and the heavy metal flows in the deltas of the Don and Kuban rivers are compared.
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Sharaf, Hesham M; Shehata, Abdalla M
2015-01-01
Heavy metals and hydrocarbons are of the most common marine pollutants around the world. The present study aimed to assess the concentration of petroleum hydrocarbons and heavy metals in tissues of the snail cyclope neritea, water and sediments from two sites of the study area (Temsah lake and Suez canal) represent polluted and unpolluted sites respectively. The results showed that, the levels of the heavy metals (Pb, Cd, Co, Mg and Zn) in the polluted area have reached harmful limits recorded globally. Lead in water, sediment and tissue of the snail reached to 0.95 ppm, 4.54 ppm and 7.93 ppm respectively. Cadmium reached 0.31 ppm, 1.15 ppm and 3.08 ppm in the corresponding samples. Cobalt was not detected in water, but it reached 1.42 ppm and 10.36 ppm in the sediment and snails tissue respectively. Magnesium in water, sediment and tissue of the snail reached 3.73 ppm, 9.44 ppm and12.6 ppm respectively. Zinc reached 0.11 ppm, 3.89 ppm and 12.60ppm in the corresponding samples. Meanwhile, hydrocarbons in the polluted area (site1) reached 110.10 μg/L, 980.15 μg/g and 228.00 μg/g in water sediment and digestive gland tissues of the snails respectively. Whereas, hydrocarbons in the unpolluted area (site2) were estimated as 14.20 μg/L, 55.60 μg/g and 22.66 μg/g in water, sediment and tissue of the snails respectively. The combination of histopathological image with monitoring of the metal level in the digestive gland of the present snail provides an important tool for early detection of impending environmental problems and potential public health issues. Petroleum hydrocarbons are toxic to the marine fauna when present above certain limit in the marine water. The major detoxification organ in molluscs is the digestive gland, which has been used as a bioindicator organ for toxicity assessment. The effect of high crude oil on the digestive gland tubules of exposed snails when examined microscopically reveals a series of histological changes which indicates that the
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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.
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The water quality, mercury, and heavy metal deposition in biological specimens from the Island Park waterways (17040202) were measured to establish ecological baseline data. Neutron activation analysis was used to identify quantitatively and qualitatively approximately 20 differ...
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Al-Hammad, Bushra Ahmed; Abd El-Salam, Magda Magdy
2016-06-01
This study was performed to determine the levels of eight heavy metals in irrigation well water and soil and to assess the suitability of some leafy green plants that are commonly cultivated in the Al-Kharj region, Saudi Arabia, for human consumption using an atomic absorption spectrometer. The mean concentrations of metals ranged from 0.0001 to 0.436 mg/L in well water and from 0.248 to 164.52 mg/kg in soil. The heavy metal concentrations showed significant differences among the different leafy green plants studied. Parsley (4.98 mg/kg) exhibited higher levels of Pb than other leafy green plants, whereas mallow (0.097 mg/kg) revealed greater amounts of Cd than other plants. All of the leafy green plants retained essential metals (Cu, Zn, Fe and Mn) more than the toxic metals (Pb and Cd). The levels of some of the metals in the leafy green plants were found to meet the FAO/WHO-recommended limits. The monitoring of heavy metals in leafy green plants must be continued because these plants are the main source of food for humans in many parts of the world and are considered to be bio-indicators for environmental pollution.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Bauman; S. Burian; M. Deo
The Utah Heavy Oil Program (UHOP) was established in June 2006 to provide multidisciplinary research support to federal and state constituents for addressing the wide-ranging issues surrounding the creation of an industry for unconventional oil production in the United States. Additionally, UHOP was to serve as an on-going source of unbiased information to the nation surrounding technical, economic, legal and environmental aspects of developing heavy oil, oil sands, and oil shale resources. UHOP fulGilled its role by completing three tasks. First, in response to the Energy Policy Act of 2005 Section 369(p), UHOP published an update report to the 1987more » technical and economic assessment of domestic heavy oil resources that was prepared by the Interstate Oil and Gas Compact Commission. The UHOP report, entitled 'A Technical, Economic, and Legal Assessment of North American Heavy Oil, Oil Sands, and Oil Shale Resources' was published in electronic and hard copy form in October 2007. Second, UHOP developed of a comprehensive, publicly accessible online repository of unconventional oil resources in North America based on the DSpace software platform. An interactive map was also developed as a source of geospatial information and as a means to interact with the repository from a geospatial setting. All documents uploaded to the repository are fully searchable by author, title, and keywords. Third, UHOP sponsored Give research projects related to unconventional fuels development. Two projects looked at issues associated with oil shale production, including oil shale pyrolysis kinetics, resource heterogeneity, and reservoir simulation. One project evaluated in situ production from Utah oil sands. Another project focused on water availability and produced water treatments. The last project considered commercial oil shale leasing from a policy, environmental, and economic perspective.« less
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Yan, Jinxia; Liu, Jingling; Li, Yi; Lang, Sisi
2014-10-01
The pollution loads continuously increased in Haihe estuary, of Tianjin, China, due to intensive human activities, especially the construction of the Haihe Gate and Lingang Industrial Area. In 2011, hydrological variability in Haihe estuary was investigated and sediments were collected. Total organic carbon (TOC), particle size, total polycyclic aromatic hydrocarbons (ΣPAHs), heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn), and benthic diatom community were analyzed. The highest concentrations of ΣPAHs and heavy metals were found near the Haihe Gate. The Shannon diversity index and the relative abundance of Coscinodiscus perforatus (RC) indicated a decreasing trend seaward. Results of Pearson correlation analysis illustrated significant relations between water current velocity and ΣPAHs (p < 0.01), Cr (p < 0.05), and RC (p < 0.05). Path analysis further indicated that water current played an important role in the distribution of PAH, Cr, and RC.
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Li, Daikun; Li, Qing; Mao, Daoyong; Bai, Ningning; Dong, Hongzhou
2017-12-01
Developing versatile materials for effective water purification is significant for environment and water source protection. Herein, a versatile bio-based material (CH-PAA-T) was reported by simple thermal cross-linking chitosan and polyacrylic acid which exhibits excellent performances for removing insoluble oil, soluble toxic dyes and heavy metal ions from water, simultaneously. The adsorption capacities are 990.1mgg -1 for methylene blue (MB) and 135.9mgg -1 for Cu 2+ , which are higher than most of present advanced absorbents. The adsorption towards organic dyes possesses high selectivity which makes CH-PAA-T be able to efficiently separate dye mixtures. The stable superoleophobicity under water endows CH-PAA-T good performance to separate toluene-in-water emulsion stabilized by Tween 80. Moreover, CH-PAA-T can be recycled for 10 times with negligible reduction of efficiency. Such versatile bio-based material is a potential candidate for water purification. Copyright © 2017. Published by Elsevier Ltd.
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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
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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.
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Ishadi, Nur Adibah Mohd; Rawi, Che Salmah Md; Ahmad, Abu Hassan; Abdul, Nurul Huda
2014-01-01
The hemipteran (Insecta) diversity in the upper part of the Kerian River Basin was low with only 8 families and 16 genera recorded at 4 study sites from 3 rivers. Water bug composition varied among sampling sites (Kruskal-Wallis χ 2 = 0.00, p<0.05) but was not affected by wet-dry seasons (Z = 0.00, p>0.05). All recorded water parameters were weakly associated with generic abundance but the biochemical oxygen demand (BOD), chemical oxygen demand (COD), Water Quality Index (WQI) and heavy metals (zinc and manganese) showed relatively strong positive or negative relations with hemipteran diversity and richness (H’ and R2). Within the ranges of measured water parameters, the WQI was negatively associated with hemipteran diversity and richness, implying the tolerance of the water bugs to the level of pollution encountered in the river basin. Based on its highest abundance and occurrence (ISI), Rhagovelia was the most important genus and along with Rheumatogonus and Paraplea, these genera were common at all study sites. In conclusion, habitat availability and suitability together with some environmental parameters influenced the abundance and composition of hemipterans in this river basin. PMID:27073600
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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.
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Chen, Lian; Zhou, Shenglu; Shi, Yaxing; Wang, Chunhui; Li, Baojie; Li, Yan; Wu, Shaohua
2018-02-15
Environmental pollution by heavy metals resulting from rapid economic development is a major concern. Soil, water, wheat, and rice samples were collected from the Lihe River Watershed in the Taihu Region (east China). In this study area, many types of industrial plants, including ceramics factories, plants working with refractory materials, and chemical plants are densely distributed and cause serious heavy metal pollution. In addition, well-developed transportation and agricultural activities are also important sources of heavy metals. Thus, the concentrations of selected heavy metals including cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in the samples were analyzed to evaluate their potential integral risk (IR) to the health of the local population. Accordingly, the spatial distribution pattern of the IR values was determined in the study. The soil in the study area showed heavy Cd pollution, whereas the pollution by other elements was relatively slight. When the proportions of grain samples in which the concentrations exceeded the tolerance limits were examined, the grains were primarily contaminated with Pb, Ni, Cd, and Zn; and less contaminated with Cu and Cr. The drinking water of the local inhabitants was safe. The average IR value was 3.53 for adults and 3.91 for children, indicating that both adults and children may experience adverse health effects. The spatial distribution pattern of the IR values among the exposed populations in the study area showed high values in the eastern and middle parts, with maximum values >5, and low values in the western part, with minimum values <2. This is consistent with the distributions of the industries and the population. The study may provide a basis for comparison to other regions both in China and worldwide. Copyright © 2017 Elsevier B.V. All rights reserved.
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Some heavy metals in Luciobarbus esocinus for public consumption and consumer protection.
Düşükcan, M; Canpolat, Ö; Eroğlu, M
2017-09-30
In this study, the concentrations of some heavy metals were determined in the muscle of Luciobarbus esocinus Heckel, 1843 and in water where they live. The results were evaluated in term of potential human risk of consumption of this fish and the relationship between the heavy metal load of fish and some of their biological aspects (weight, length and sex). In addition, the accumulation factor of heavy metals in the muscle of L. esocinus were also determined. The Cr, Pb and Ni were not found in detectable levels according to results obtained by ICP. Only Cu, Zn and Fe were detected. It was found that heavy metals concentrations in the muscle of L. esocinus were higher than that in the water. The concentration of heavy metals showed differences according to weight, length and sex of fish. The results were discussed and compared with tolerable values for heavy metals provided from the EPA, FAO and WHO in order to determine whether this fish species has any risk for human consumption.
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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.
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Heavy metals from Kueishantao shallow-sea hydrothermal vents, offshore northeast Taiwan
NASA Astrophysics Data System (ADS)
Chen, Xue-Gang; Lyu, Shuang-Shuang; Garbe-Schönberg, Dieter; Lebrato, Mario; Li, Xiaohu; Zhang, Hai-Yan; Zhang, Ping-Ping; Chen, Chen-Tung Arthur; Ye, Ying
2018-04-01
Shallow water hydrothermal vents are a source of heavy metals leading to their accumulation in marine organisms that manage to live under extreme environmental conditions. This is the case at Kueishantao (KST) shallow-sea vents system offshore northeast Taiwan, where the heavy metal distribution in vent fluids and ambient seawater is poorly understood. This shallow vent is an excellent natural laboratory to understand how heavy and volatile metals behave in the nearby water column and ecosystem. Here, we investigated the submarine venting of heavy metals from KST field and its impact on ambient surface seawater. The total heavy metal concentrations in the vent fluids and vertical plumes were 1-3 orders of magnitude higher than the overlying seawater values. When compared with deep-sea hydrothermal systems, the estimated KST end-member fluids exhibited much lower concentrations of transition metals (e.g., Fe and Mn) but comparable concentrations of toxic metals such as Pb and As. This may be attributed to the lower temperature of the KST reaction zone and transporting fluids. Most of the heavy metals (Fe, Mn, As, Y, and Ba) in the plumes and seawater mainly originated from hydrothermal venting, while Cd and Pb were largely contributed by external sources such as contaminated waters (anthropogenic origin). The spatial distribution of heavy metals in the surface seawater indicated that seafloor venting impacts ambient seawater. The measurable influence of KST hydrothermal activity, however, was quite localized and limited to an area of < 1 km2. The estimated annual fluxes of heavy metals emanating from the yellow KST hydrothermal vent were: 430-2600 kg Fe, 24-145 kg Mn, 5-32 kg Ba, 10-60 kg As, 0.3-1.9 kg Cd, and 2-10 kg Pb. This study provides important data on heavy metals from a shallow-sea hydrothermal field, and it helps to better understand the environmental impact of submarine shallow hydrothermal venting.
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Implications of soil pollution with heavy metals for public health
NASA Astrophysics Data System (ADS)
Juozulynas, Algirdas; Jurgelėnas, Antanas; Butkienė, Birutė; Greičiūtė, Kristina; Savičiūtė, Rasa
2008-01-01
Soil of military grounds is often polluted with heavy metals. Their concentrations may be dosens of times higher in polluted regions. The affected soils are permeable, so the pollutions can get into water and spread to the environment. Into human and animal organisms they can get with food and water. Heavy metals are very dangerous for people's health, and we must know their accumulation places, intensity of scatter and integral risk for health. The purpose of this work was to establish links between zones polluted with heavy metals and morbidity caused by pollution with heavy metals. The morbidity caused by heavy metals (Pb, Cu, Zn, Ca and other) in the polluted regions is 1.4-1.5 times higher for adults and teenagers and 1.5-3.9 times higher for children aged under 14 years than the mean morbidity of the same diseases in Lithuania. Hypothetically, it is possible to prognosticate that this problem will grow in future because the ratio of the newly registered and the existing cases of morbidity for children aged under 14 years is 1.3-1.5 times higher than for adults.
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Bai, Yang; Wang, Min; Peng, Chi; Alatalo, Juha M
2016-03-01
We investigated the horizontal and vertical distribution of heavy metals (Hg, Pb, Zn, Cu, Cd, As, Ni, and Cr) in soils in the water source protection zone for Shanghai to study the origins of these metals, their connections with urbanization, and their potential risk posed on the ecosystem. Determination of metal concentrations in 50 topsoil samples and nine soil profiles indicated that Hg, Pb, Zn, and Cu were present in significantly higher concentrations in topsoil than in deep soil layers. The spatial distributions of Hg, Pb, Zn, and Cu and contamination hotspots for these metals in the study area were similar to those near heavy industries and urban built-up areas. Emissions from automobiles resulted in increased soil concentrations of Cu, Pb, and Zn along roadsides, while high concentrations of Hg in the soil resulted from recent atmospheric deposition. Calculation of the potential ecological risk indicated that the integrative risk of these heavy metals in most areas was low, but a few sites surrounding high density of factories showed moderate risks.
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Kim, Min-Suk; Min, Hyun-Gi; Koo, Namin; Park, Jeongsik; Lee, Sang-Hwan; Bak, Gwan-In; Kim, Jeong-Gyu
2014-12-15
Spent coffee grounds (SCG) and charred spent coffee grounds (SCG-char) have been widely used to adsorb or to amend heavy metals that contaminate water or soil and their success is usually assessed by chemical analysis. In this work, the effects of SCG and SCG-char on metal-contaminated water and soil were evaluated using chemical and biological assessments; a phytotoxicity test using bok choy (Brassica campestris L. ssp. chinensis Jusl.) was conducted for the biological assessment. When SCG and SCG-char were applied to acid mine drainage, the heavy metal concentrations were decreased and the pH was increased. However, for SCG, the phytotoxicity increased because a massive amount of dissolved organic carbon was released from SCG. In contrast, SCG-char did not exhibit this phenomenon because any easily released organic matter was removed during pyrolysis. While the bioavailable heavy metal content decreased in soils treated with SCG or SCG-char, the phytotoxicity only rose after SCG treatment. According to our statistical methodology, bioavailable Pb, Cu and As, as well as the electrical conductivity representing an increase in organic content, affected the phytotoxicity of soil. Therefore, applying SCG during environment remediation requires careful biological assessments and evaluations of the efficiency of this remediation technology. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Heavy metal biomonitoring and phytoremediation potentialities of aquatic macrophytes in River Nile.
Fawzy, Manal Ahmed; Badr, Nadia El-sayed; El-Khatib, Ahmed; Abo-El-Kassem, Amany
2012-03-01
The concentrations of Cd, Cu, Pb, and Zn in sediments, water, and different plant organs of six aquatic vascular plant species, Ceratophyllum demersum L. Echinochloa pyramidalis (Lam.) Hitchc. & Chase; Eichhornia crassipes (Mart.) Solms-Laub; Myriophyllum spicatum L.; Phragmites australis (Cav.) Trin. ex Steud; and Typha domingensis (Pers.) Poir. ex Steud, growing naturally in the Nile system (Sohag Governorate), were investigated. The aim was to define which species and which plant organs exhibit the greatest accumulation and evaluate whether these species could be usefully employed in biomonitoring and phytoremediation programs. The recorded metals in water samples were above the standard levels of both US Environmental Protection Agency and Egyptian Environmental Affairs Agency except for Pb. The concentrations of heavy metals in water, sediments, and plants possess the same trend: Zn > Cu > Pb > Cd which reflects the biomonitoring potentialities of the investigated plant species. Generally, the variation of heavy element concentrations in water and sediments in relation to site and season, as assessed by two-way repeated measured ANOVA, was significant (p < 0.05). However, insignificant variations were observed in the concentrations of Pb and Cd in sediments in relation to season and of Cu and Zn in relation to site. Results also showed that the selectivity of the heavy elements for the investigated plants varied significantly (p < 0.05) with species variation. The accumulation capability of the investigated species could be arranged according to this pattern: C. demersum > E. crassipes > M. spicatum > E. pyramidalis > T. domingensis > P. australis. On the basis of the element concentrations, roots of all the studied species contain higher concentrations of Cu and Zn than shoots while leaves usually acquire the highest concentrations of Pb. Cd concentrations among different plant organs are comparable except in M. spicatum where the highest Cd concentrations
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Leaching Properties of Naturally Occurring Heavy Metals from Soils
NASA Astrophysics Data System (ADS)
Zhang, M.; Hoshino, M.; Yoshikawa, M.; Hara, J.; Sugita, H.
2014-12-01
The major threats to human health from heavy metals are associated with exposure to arsenic, lead, cadmium, chromium, mercury, as well as some other elements. The effects of such heavy metals on human health have been extensively studied and reviewed by international organizations such as WHO. Due to their toxicity, heavy metal contaminations have been regulated by national environmental standards in many countries, and/or laws such as the Soil Contamination Countermeasures Act in Japan. Leaching of naturally occurring heavy metals from the soils, especially those around abandoned metal mines into surrounding water systems, either groundwater or surface water systems, is one of the major pathways of exposure. Therefore, understanding the leaching properties of toxic heavy metals from naturally polluted soils is of fundamentally importance for effectively managing abandoned metal mines, excavated rocks discharged from infrastructure constructions such as tunneling, and/or selecting a pertinent countermeasure against pollution when it is necessary. In this study, soil samples taken from the surroundings of abandoned metal mines in different regions in Japan were collected and analyzed. The samples contained multiple heavy metals such as lead, arsenic and chromium. Standard leaching test and sequential leaching test considering different forms of contaminants, such as trivalent and pentavalent arsenics, and trivalent and hexavalent chromiums, together with standard test for evaluating total concentration, X-ray Fluorescence Analysis (XRF), X-ray diffraction analysis (XRD) and Cation Exchange Capacity (CEC) tests were performed. In addition, sequential leaching tests were performed to evaluate long-term leaching properties of lead from representative samples. This presentation introduces the details of the above experimental study, discusses the relationships among leaching properties and chemical and mineral compositions, indicates the difficulties associated with
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Lin, Yi-Liang; Wang, Po-Yen; Hsieh, Ling-Ling; Ku, Kuan-Hsuan; Yeh, Yun-Tai; Wu, Chien-Hou
2009-09-04
A simple and sensitive method is described for the determination of picomolar amounts of C(1)-C(9) linear aliphatic aldehydes in waters containing heavy metal ions. In this method, aldehydes were first derivatized with 2,4-dinitrophenylhydrazine (DNPH) at optimized pH 1.8 for 30 min and analyzed by HPLC with UV detector at 365 nm. Factors affecting the derivatization reaction of aldehydes and DNPH were investigated. Cupric ion, an example of heavy metals, is a common oxidative reagent, which may oxidize DNPH and greatly interfere with the determination of aldehydes. EDTA was used to effectively mask the interferences by heavy metal ions. The method detection limits for direct injection of derivatized most aldehydes except formaldehyde were of the order of 7-28 nM. The detection limit can be further lowered by using off-line C(18) adsorption cartridge enrichment. The recoveries of C(1)-C(9) aldehydes were 93-115% with a relative standard deviation of 3.6-8.1% at the 0.1 microM level for aldehydes. The HPLC-DNPH method has been applied for determining aldehyde photoproducts from Cu(II)-amino acid complex systems.
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ERIC Educational Resources Information Center
Abdullah, Mohd. Harun; Sidi, Jovita; Aris, Ahmad Zaharin
2007-01-01
Concentrations of heavy metals (Cd, Cu, Cr, Pb and Zn) in tissues of Meretrix meretrix Roding (M. meretrix R.), water and sediments from two estuaries were determined. One estuary is located in an urban area of Kota Kinabalu (Likas estuary) and the other in a rural district of Kota Belud (Kota Belud estuary), where both are in Sabah, North of…
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NASA Astrophysics Data System (ADS)
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
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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.
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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
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Ormrod, James S
2012-10-01
This paper begins by highlighting the necessity of combining sociological and psychoanalytic approaches in the study of social movements, but acknowledges that psychobiographical studies of prominent movement leaders sit uneasily within the sociological tradition. The author attempts to illustrate that leader psychobiography can make a contribution to understanding social movements, however, provided it offers a way into understanding broader psychosocial issues within the movement. This is achieved through a psychobiographical portrait of Bruce Gagnon, a leader within the outer space protection movement. The author argues for the central importance of both paranoid-schizoid and depressive mechanisms throughout Gagnon's activist career. These eventually came to underpin Gagnon's commitment to protecting outer space as a Kleinian "good object." The paper concludes by suggesting how Gagnon's psychobiography might be instructive in attempts to understand the wider movement, utilizing Erikson's model for psychohistorical study as a framework.
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Tiwari, Ashwani Kumar; Singh, Prasoon Kumar; Singh, Abhay Kumar; De Maio, Marina
2016-04-01
Heavy metal (Al, As, Ba, Cr, Cu, Fe, Mn, Ni, Se and Zn) concentration in sixty-six groundwater samples of the West Bokaro coalfield were analyzed using inductively coupled plasma-mass spectroscopy for determination of seasonal fluctuation, source apportionment and heavy metal pollution index (HPI). Metal concentrations were found higher in the pre-monsoon season as compared to the post-monsoon season. Geographic information system (GIS) tool was attributed to study the metals risk in groundwater of the West Bokaro coalfield. The results show that 94 % of water samples were found as low class and 6 % of water samples were in medium class in the post-monsoon season. However, 79 % of water samples were found in low class, 18 % in medium class and 3 % in high class in the pre-monsoon season. The HPI values were below the critical pollution index value of 100. The concentrations of Al, Fe, Mn, and Ni are exceeding the desirable limits in many groundwater samples in both seasons.
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Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops*
Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar
2007-01-01
Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary
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Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops.
Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar
2007-01-01
Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary
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Toxicity of irradiated advanced heavy water reactor fuels.
Priest, N D; Richardson, R B; Edwards, G W R
2013-02-01
The good neutron economy and online refueling capability of the CANDU® heavy water moderated reactor (HWR) enable it to use many different fuels such as low enriched uranium (LEU), plutonium, or thorium, in addition to its traditional natural uranium (NU) fuel. The toxicity and radiological protection methods for these proposed fuels, unlike those for NU, are not well established. This study uses software to compare the fuel composition and toxicity of irradiated NU fuel against those of two irradiated advanced HWR fuel bundles as a function of post-irradiation time. The first bundle investigated is a CANFLEX® low void reactor fuel (LVRF), of which only the dysprosium-poisoned central element, and not the outer 42 LEU elements, is specifically analyzed. The second bundle investigated is a heterogeneous high-burnup (LEU,Th)O(2) fuelled bundle, whose two components (LEU in the outer 35 elements and thorium in the central eight elements) are analyzed separately. The LVRF central element was estimated to have a much lower toxicity than that of NU at all times after shutdown. Both the high burnup LEU and the thorium fuel had similar toxicity to NU at shutdown, but due to the creation of such inhalation hazards as (238)Pu, (240)Pu, (242)Am, (242)Cm, and (244)Cm (in high burnup LEU), and (232)U and (228)Th (in irradiated thorium), the toxicity of these fuels was almost double that of irradiated NU after 2,700 d of cooling. New urine bioassay methods for higher actinoids and the analysis of thorium in fecal samples are recommended to assess the internal dose from these two fuels.
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Fabisch, Maria; Freyer, Gina; Johnson, Carol A.; Buchel, Georg; Akob, Denise M.; Neu, Thomas R.; Kusel, Kirsten
2016-01-01
Heavy metal-contaminated, pH 6 mine water discharge created new streams and iron-rich terraces at a creek bank in a former uranium-mining area near Ronneburg, Germany. The transition from microoxic groundwater with ~5 mm Fe(II) to oxic surface water may provide a suitable habitat for microaerobic iron-oxidizing bacteria (FeOB). In this study, we investigated the potential contribution of these FeOB to iron oxidation and metal retention in this high-metal environment. We (i) identified and quantified FeOB in water and sediment at the outflow, terraces, and creek, (ii) studied the composition of biogenic iron oxides (Gallionella-like twisted stalks) with scanning and transmission electron microscopy (SEM, TEM) as well as confocal laser scanning microscopy (CLSM), and (iii) examined the metal distribution in sediments. Using quantitative PCR, a very high abundance of FeOB was demonstrated at all sites over a 6-month study period. Gallionella spp. clearly dominated the communities, accounting for up to 88% ofBacteria, with a minor contribution of other FeOB such as Sideroxydans spp. and ‘Ferrovum myxofaciens’. Classical 16S rRNA gene cloning showed that 96% of the Gallionella-related sequences had ≥97% identity to the putatively metal-tolerant ‘Gallionella capsiferriformans ES-2’, in addition to known stalk formers such as Gallionella ferruginea and Gallionellaceae strain R-1. Twisted stalks from glass slides incubated in water and sediment were composed of the Fe(III) oxyhydroxide ferrihydrite, as well as polysaccharides. SEM and scanning TEM-energy-dispersive X-ray spectroscopy revealed that stalk material contained Cu and Sn, demonstrating the association of heavy metals with biogenic iron oxides and the potential for metal retention by these stalks. Sequential extraction of sediments suggested that Cu (52–61% of total sediment Cu) and other heavy metals were primarily bound to the iron oxide fractions. These results show the importance of
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Li, Bingbing; Zhou, Feng; Huang, Kai; Wang, Yipei; Mei, Surong; Zhou, Yikai; Jing, Tao
2017-01-01
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. PMID:28225082
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NASA Astrophysics Data System (ADS)
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.
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Zhang, Junyi; Zhu, Congming; Guan, Rui; Xiong, Zhipeng; Zhang, Wen; Shi, Junzhe; Sheng, Yi; Zhu, Bingchuan; Tu, Jing; Ge, Qinyu; Chen, Ting; Lu, Zuhong
2017-05-01
Understanding of the bacterial community structure in drinking water resources helps to enhance the security of municipal water supplies. In this study, bacterial communities were surveyed in water and sediment during a heavy cyanobacterial bloom in a drinking water resource of Lake Taihu, China. A total of 325,317 high-quality sequences were obtained from different 16S ribosomal RNA (rRNA) regions (V3, V4, and V6) using the Miseq sequencing platform. A notable difference was shown between the water and sediment samples, as predominated by Cyanobacteria, Proteobacteria, and Actinobacteria in the water and Proteobacteria, Chloroflexi, and Verrucomicrobia in the sediment, respectively. The LD12 family dominated the water surface and was tightly associated with related indicators of cyanobacterial propagation, indicating involvement in the massive proliferation of cyanobacterial blooms. Alternatively, the genus Nitrospira dominated the sediment samples, which indicates that nitrite oxidation was very active in the sediment. Although pathogenic bacteria were not detected in a large amount, some genera such as Mycobacterium, Acinetobacter, and Legionella were still identified but in very low abundance. In addition, the effects of different V regions on bacterial diversity survey were evaluated. Overall, V4 and V3 were proven to be more promising V regions for bacterial diversity survey in water and sediment samples during heavy water blooms in Lake Taihu, respectively. As longer, cheaper, and faster DNA sequencing technologies become more accessible, we expect that bacterial community structures based on 16S rRNA amplicons as an indicator could be used alongside with physical and chemical indicators, to conduct comprehensive assessments for drinking water resource management.
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Dahui, Liu; Na, Xu; Li, Wang; Xiuming, Cui; Lanping, Guo; Zhihui, Zhang; Jiajin, Wang; Ye, Yang
2014-01-01
The quality and safety of Panax notoginseng products has become a focus of concern in recent years. Contamination with heavy metals is one of the important factors as to P. notoginseng safety. Cleaning treatments can remove dust, soil, impurities or even heavy metals and pesticide residues on agricultural products. But effects of cleaning treatments on the heavy metal content of P. notoginseng roots have still not been studied. In order to elucidate this issue, the effects of five different cleaning treatments (CK, no treatment; T1, warm water (50°C) washing; T2, tap water (10°C) washing; T3, drying followed by polishing; and T4, drying followed by tap water (10°C) washing) on P. notoginseng roots' heavy metal (Cu, Pb, Cd, As and Hg) contents were studied. The results showed that heavy metal (all five) content in the three parts all followed the order of hair root > rhizome > root tuber under the same treatment. Heavy metal removals were in the order of Hg > As > Pb > Cu > Cd. Removal efficiencies of the four treatments were in the order of T2 > T1 > T3 > T4. Treatments (T1-T4) could decrease the contents of heavy metal in P. notoginseng root significantly. Compared with the requirements of WM/T2-2004, P. notoginseng roots' heavy metal contents of Cu, Pb, As and Hg were safe under treatments T1 and T2. In conclusion, the cleaning process after production was necessary and could reduce the content of heavy metals significantly. Fresh P. notoginseng root washed with warm water (T2) was the most efficient treatment to remove heavy metal and should be applied in production.
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Aggregation study in mixture surfactant system TX-100+SDS in heavy water solutions by SANS method
NASA Astrophysics Data System (ADS)
Rajewska, A.; Islamov, A. Kh.; Bakeeva, R. F.
2018-03-01
The mixing of amphiphiles in water may lead to the formation of mixed micelles which often present new properties with respect to the pure component solutions [1,2]. The mixture system of classic surfactants SDS (sodium dodecyl sulfate)+TX-100(p-(1,1,3,3- tetramethyl) poly(oxyethylene) (anionic + non-ionic) in heavy water solutions was investigated at temperatures 30°, 50°, 70°C for compositions 1:1, 2:1, 3:1 by the small-angle neutron scattering(SANS) method on spectrometer (‘YuMO’) at the IBR-2 pulsed neutron source at FLNP, JINR in Dubna (Russia). Measurements have covered Q range from 8x10-3 to 0.4 Å-1. From the measured dependence of the scattered intensity on the scattering angle, we derived the size, shape of micelles, aggregation number at various compositions and temperatures. The size of mixed micelle is a weak function of the mixing ratio between the two components.
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[Mapping Critical Loads of Heavy Metals for Soil Based on Different Environmental Effects].
Shi, Ya-xing; Wu, Shao-hua; Zhou, Sheng-lu; Wang, Chun-hui; Chen, Hao
2015-12-01
China's rapid development of industrialization and urbanization causes the growing problem of heavy metal pollution of soil, threatening environment and human health. Therefore, prevention and management of heavy metal pollution become particularly important. Critical loads of heavy metals are an important management tool that can be utilized to prevent the occurrence of heavy metal pollution. Our study was based on three cases: status balance, water environmental effects and health risks. We used the steady-state mass balance equation to calculate the critical loads of Cd, Cu, Pb, Zn at different effect levels and analyze the values and spatial variation of critical loads. In addition, we used the annual input fluxes of heavy metals of the agro-ecosystem in the Yangtze River delta and China to estimate the proportion of area with exceedance of critical loads. The results demonstrated that the critical load value of Cd was the minimum, and the values of Cu and Zn were lager. There were spatial differences among the critical loads of four elements in the study area, lower critical loads areas mainly occurred in woodland and high value areas distributed in the east and southwest of the study area, while median values and the medium high areas mainly occurred in farmland. Comparing the input fluxes of heavy metals, we found that Pb and Zn in more than 90% of the area exceeded the critical loads under different environmental effects in the study area. The critical load exceedance of Cd mainly occurred under the status balance and the water environmental effect, while Cu under the status balance and water environmental effect with a higher proportion of exceeded areas. Critical loads of heavy metals at different effect levels in this study could serve as a reference from effective control of the emissions of heavy metals and to prevent the occurrence of heavy metal pollution.
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Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.
2013-07-01
The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in themore » Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)« less
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Plankton And Heavy Metal Correlation From Commercial Vessels In Port Of Tanjung Emas Semarang
NASA Astrophysics Data System (ADS)
Tjahjono, Agus; Bambang, Aziz Nur; Anggoro, Sutrisno
2018-02-01
The commercial vessels activity have a big role to increase the flow of number of cargoes from a port to another port. However, the impact of these activities are the disposal of ballast water from port area to the destination port. The purpose of this research was to analyze the correlation of phytoplankton, zooplankton, and heavy metal which were contained inside the ballast water of commercial vessel towards in waters of the port of Tanjung Emas Semarang. The concentration of heavy metal either from commercial vessels or the waters in port area analyzed by Atomic Absorption Spectrophotometer (AAS). The result showed that the correlation of zooplankton and phytoplankton in the water ballast at commercial vessels have a medium correlation to zooplankton and phytoplankton in waters of Port of Tanjung Emas Semarang (PTES) were 48.9% and 58.3%. Correlation of heavy metal Cd, Zn, Cu, Zn and Pb in ballast water of commercial vessel toward each metal in waters of PTES area has a strong correlation in contribution were 76.7%, 75.6%, 71.4% and 73.8%. It showed us that the loading activity of commercial vessels in port are contributed towards the pollution in waters.
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Khan, Muhammad Iftikhar; Gulfam, Naila; Siraj, Muhammad; Zaidi, Farrah; Ahmadullah; Abidullah; Fatima, Syeda Hira; Noreen, Shumaila; Hamidullah; Shah, Zafar Ali; Qadir, Fazli
2018-01-01
The present investigation aimed to assess the concentrations of selected heavy metals in water and sediments and their bioaccumulation in tissues of freshwater mussels and their histopathological effects on the digestive gland, gills, and gonads of Anodonta cygnea. Water, sediments, and freshwater mussel samples were collected at four sites, that is, reference and polluted sites, along the Kabul River, Khyber Pakhtunkhwa. The polluted sites were receiving effluents from the industrial, agricultural, municipal, and domestic sources. The order of metals in the water was Zn > Pb > Ni > Cu > Mn > Fe > Cr > Cd, in sediments the order was Fe > Zn > Cr > Ni > Mn > Pb > Cu > Cd, and in the soft tissues the order was Fe > Zn > Mn > Pb > Cu > Cr > Ni > Cd. Histopathological alterations observed in polluted sites of Kabul River were inflammation, hydropic vacuolation, and lipofuscin pigments (in digestive gland), gill lamellar fusion, dilated hemolymphatic sinus, clumping, and generation of cilia and hemocytic infiltration (in gills), and atresia, necrosis, granulocytoma, hemocytic infiltration, and lipofuscin pigments (in gonads). The histopathological alterations in the organs of Anodonta cygnea can be considered as reliable biomarkers in biomonitoring of heavy metal pollution in aquatic ecosystems. PMID:29693003
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Weidman, Jacob L; Mulvenna, Ryan A; Boudouris, Bryan W; Phillip, William A
2017-06-07
Heavy metal contamination of water supplies poses a serious threat to public health, prompting the development of novel and sustainable treatment technologies. One promising approach is to molecularly engineer the chemical affinity of a material for the targeted removal of specific molecules from solution. In this work, nanoporous polymer thin films generated from tailor-made block polymers were functionalized with the bio-inspired moieties glutathione and cysteamine for the removal of heavy metal ions, including lead and cadmium, from aqueous solutions. In a single equilibrium stage, the films achieved removal rates of the ions in excess of 95%, which was consistent with predictions based on the engineered material properties. In a flow-through configuration, the thin films achieved an even greater removal rate of the metal ions. Furthermore, in mixed ion solutions the capacity of the thin films, and corresponding removal rates, did not demonstrate any reduction due to competitive adsorption effects. After such experiments the material was repeatedly regenerated quickly with no observed loss in capacity. Thus, these membranes provide a sustainable platform for the efficient purification of lead- and cadmium-contaminated water sources to safe levels. Moreover, their straightforward chemical modifications suggest that they could be engineered to treat sources containing other recalcitrant environmental contaminants as well.
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Community Heavy Metal Exposure, San Francisco, California
NASA Astrophysics Data System (ADS)
Chavez, A.; Devine, M.; Ho, T.; Zapata, I.; Bissell, M.; Neiss, J.
2008-12-01
Heavy metals are natural elements that generally occur in minute concentrations in the earth's crust. While some of these elements, in small quantities, are vital to life, most are harmful in larger doses. Various industrial and agricultural processes can result in dangerously high concentrations of heavy metals in our environment. Consequently, humans can be exposed to unsafe levels of these elements via the air we breathe, the water and food we consume, and the many products we use. During a two week study we collected numerous samples of sediments, water, food, and household items from around the San Francisco Bay Area that represent industrial, agricultural, and urban/residential settings. We analyzed these samples for Mercury (Hg), Lead (Pb), and Arsenic (As). Our goal was to examine the extent of our exposure to heavy metals in our daily lives. We discovered that many of the common foods and materials in our lives have become contaminated with unhealthy concentrations of these metals. Of our food samples, many exceeded the EPA's Maximum Contaminant Levels (MCL) set for each metal. Meats (fish, chicken, and beef) had higher amounts of each metal than did non-meat items. Heavy metals were also prevalent in varying concentrations in the environment. While many of our samples exceeded the EPA's Sediment Screening Level (SSL) for As, only two other samples surpassed the SSL set for Pb, and zero of our samples exceeded the SSL for Hg. Because of the serious health effects that can result from over-exposure to heavy metals, the information obtained in this study should be used to influence our future dietary and recreational habits.
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Water Quality Characteristics of Sembrong Dam Reservoir, Johor, Malaysia
NASA Astrophysics Data System (ADS)
Mohd-Asharuddin, S.; Zayadi, N.; Rasit, W.; Othman, N.
2016-07-01
A study of water quality and heavy metal content in Sembrong Dam water was conducted from April - August 2015. A total of 12 water quality parameters and 6 heavy metals were measured and classified based on the Interim National Water Quality Standard of Malaysia (INWQS). The measured and analyzed parameter variables were divided into three main categories which include physical, chemical and heavy metal contents. Physical and chemical parameter variables were temperature, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), turbidity, pH, nitrate, phosphate, ammonium, conductivity and salinity. The heavy metals measured were copper (Cu), lead (Pb), aluminium (Al), chromium (Cr), ferum (Fe) and zinc (Zn). According to INWQS, the water salinity, conductivity, BOD, TSS and nitrate level fall under Class I, while the Ph, DO and turbidity lie under Class IIA. Furthermore, values of COD and ammonium were classified under Class III. The result also indicates that the Sembrong Dam water are not polluted with heavy metals since all heavy metal readings recorded were falls far below Class I.
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NASA Astrophysics Data System (ADS)
Vetrimurugan, E.; Brindha, K.; Elango, L.; Ndwandwe, Osman Muzi
2017-10-01
Drinking water containing heavy metals above the maximum permissible limits cause potential risk to human health. The aim of this study was to determine the groundwater suitability for drinking use based on heavy metal concentration and the associated human exposure risk in an intensively irrigated part of the Cauvery river basin, Tamil Nadu, India. Sixteen heavy metals analysed were in the order of dominance of chromium < zinc < copper < cadmium < cobalt < iron < aluminium < nickel < titanium < zirconium < boron < silver < manganese < lead < lithium < silicon in groundwater. Chromium and zinc were within permissible limits of the Bureau of Indian Standards for drinking water quality, and silver, lead and nickel were above limits in all the groundwater samples. In less than 50 % of the groundwater samples, aluminium, boron, cadmium, copper, iron and manganese exceeded their individual permissible limits. Heavy metal pollution index based on 11 heavy metals indicated that groundwater quality of this area is poor-to-unsuitable. Non-carcinogenic risk for humans due to ingestion of groundwater through drinking water pathway was very high for infants, children and adults. Silver, lead, nickel, cadmium and manganese largely contributed to the health hazard. Sources of heavy metals were identified to be geological and from human activities, i.e., application of fertilizers in agricultural fields, seawater intrusion due to intensive pumping for agriculture and wastewater from industries. Groundwater and surface water in this area pose large threat due to high levels of heavy metals, and it is necessary to avoid this water for drinking due to potential risk of health hazard. This study also demonstrated the application of HPI and human exposure hazard index to study the groundwater quality based on heavy metals' concentration.
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Ma, Xiao-ling; Liu, Jing-jun; Deng, Feng-yu; Zuo, Hang; Huang, Fang; Zhang, Li-yang; Liu, Ying
2015-10-01
The content characteristics, pollution evaluation and source identification of 6 heavy Metals (Cd, Pb, Cr, As, Cu and Zn) in filtered water and 9 heavy Metals (Cd, Pb, Cr, Ni, Cu, V, Co, Zn and Mn) in suspended particles from 10 sampling sites such as Zhaojunfuqiao (S1) and Baotoufuqiao (S2), etc. from Gansu, Ningxia and Inner Mongolia sections of the Yellow River in 2012 Wet Season were studied to understand the condition of the heavy metal pollution in Gansu, Ningxia and Inner Mongolia Sections of the Yellow River by using high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). Multivariate geochemical approaches and statistical analysis were also exploited for assessing the level of heavy metals in filtered water and suspended particles from studied area. The results showed that in filtering water, only the concentrations of Cr exceeded the standard value of Environmental Quality Standard for Surface Water (GB3838-2002) and were the highest (74.8-94.7 μg x L(-1)) among all elements in 10 sampling sites; Single factor pollution index (I(i)) results suggested that the water quality in all sampling sites were contaminated by both Cr and total nitrogen (TN), with the exception of TN in Baotoufuqiao (S2); Integrated Nemerow pollution index (I) indicated that the I values in all sampling sites were between 1-2 (light pollution), which implied that the water quality in Gansu, Ningxia and Inner Mongolia sections, especially downstream sections (S1-S6) of the Yellow River wasn't an ideal source for drinking and using in aquaculture any more. In suspended particles, concentrations of heavy metals were relatively higher than their soil background values in 10 sampling sites, except Ni in S10 (34.7 μg x L(-1)). Index of geo-accumulation (I(geo)) indicated that the I(geo) values of Pb, Cr, Ni, Cu, V, Co, Zn and Mn in all sampling sites were less than 1 (unpolluted or unpolluted-moderately polluted), respectively, while I(geo)Cd were the highest in 10
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Zhang, Lei; Qin, Yan-wen; Ma, Ying-qun; Zhao, Yan-min; Shi, Yao
2014-09-01
The aim of this article was to explore the pollution level of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area. The contents and spatial distribution of As, Cd, Cr, Cu, Ph and Zn in surface water, suspended solids and surface sediments were analyzed respectively. The integrated pollution index and geoaccumulation index were used to evaluate the contamination degree of heavy metals in surface water and surface sediments respectively. The results indicated that the contents of heavy metals in surface water was in the order of Pb < Cu < Cd < Cr < As < Zn. The heavy metal contents in surface water increased from river to sea. Compared with the contents of heavy metals in surface water of the typical domestic estuary in China, the overall contents of heavy metals in surface water were at a higher level. The contents of heavy metals in suspended solids was in the order of Cd < Cu < As < Cr
heavy metals in surface sediments was in the order of Cd heavy metals in water, suspended solids and sediment. In particular, the effects of salinity and suspended solids matter were most significant. The integrated pollution index assessment showed that the water quality was good except individual stations. The geoaccumulation index assessment showed that As was the major pollution element in surface sediments. -
A fluorometric paper-based sensor array for the discrimination of heavy-metal ions.
Feng, Liang; Li, Hui; Niu, Li-Ya; Guan, Ying-Shi; Duan, Chun-Feng; Guan, Ya-Feng; Tung, Chen-Ho; Yang, Qing-Zheng
2013-04-15
A fluorometric paper-based sensor array has been developed for the sensitive and convenient determination of seven heavy-metal ions at their wastewater discharge standard concentrations. Combining with nine cross-reactive BODIPY fluorescent indicators and array technologies-based pattern-recognition, we have obtained the discrimination capability of seven different heavy-metal ions at their wastewater discharge standard concentrations. After the immobilization of indicators and the enrichment of analytes, identification of the heavy-metal ions was readily acquired using a standard chemometric approach. Clear differentiation among heavy-metal ions as a function of concentration was also achieved, even down to 10(-7)M. A semi-quantitative estimation of the heavy-metal ion concentration was obtained by comparing color changes with a set of known concentrations. The sensor array was tentatively investigated in spiked tap water and sea water, and showed possible feasibility for real sample testing. Copyright © 2013 Elsevier B.V. All rights reserved.
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Polymer-Coated Nanoparticles for Reversible Emulsification and Recovery of Heavy Oil.
Qi, Luqing; Song, Chen; Wang, Tianxiao; Li, Qilin; Hirasaki, George J; Verduzco, Rafael
2018-06-05
Heavy crude oil has poor solubility and a high density, making recovery and transport much more difficult and expensive than for light crude oil. Emulsifiers can be used to produce low viscosity oil-in-water emulsions for recovery and transport, but subsequent demulsification can be challenging. Here, we develop and implement interfacially active, pH-responsive polymer-coated nanoparticles (PNPs) to reversibly stabilize, recover, and break oil/water emulsions through variation of solution pH. Silica particles with poly(2-(dimethylamino)ethyl methacrylate) (DMAEMA) chains covalently grafted to the surface are prepared although a reversible addition fragmentation chain transfer grafting-through technique. The resulting DMAEMA PNPs can stabilize emulsions of high viscosity Canadian heavy oil at PNP concentrations as low as 0.1 wt % and at neutral pH. The performance of the DMAEMA PNPs exceeds that of DMAEMA homopolymer additives, which we attribute to the larger size and irreversible adsorption of DMAEMA PNPs to the oil/water interface. After recovery, the emulsion can be destabilized by the addition of acid to reduce pH, resulting in separation and settling of the heavy oil from the aqueous phase. Recovery of more than 10 wt % of the crude heavy oil-in-place is achieved by flooding with aqueous solution of 0.1 wt % DMAEMA PNPs without any additional surfactant or chemical. This work demonstrates the applicability of PNPs as surface active materials for enhanced oil recovery processes and for heavy oil transport.
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Izah, Sylvester Chibueze; Inyang, Iniobong Reuben; Angaye, Tariwari C. N.; Okowa, Ifeoma Peace
2016-01-01
Beverages are consumed in Nigeria irrespective of age, sex, and socioeconomic status. Beverages may be alcoholic (wine, spirits, and beers) or non-alcoholic (soft drink, energy drinks, candies, chocolates, milks). Notwithstanding, most beverages are packed in cans, bottles, and plastics. This paper reviews the concentration of heavy metals from some commercially-packaged beverages consumed in Nigeria. The study found that heavy metal concentrations, including iron, mercury, tin, antimony, cadmium, zinc, copper, chromium, lead, and manganese, seldom exceed the maximum contaminant level recommended by the Standard Organization of Nigeria (SON) and the World Health Organization (WHO) as applicable to drinking water resources. The occurrence of heavy metals in the beverages could have resulted from the feedstocks and water used in their production. Consumption of beverages high in heavy metal could be toxic and cause adverse effect to human health, depending on the rate of exposure and accumulation dosage. This study concludes by suggesting that heavy metal concentration in the feedstocks and water should be monitored by producers, and its concentration in beverages should also be monitored by appropriate regulatory agencies. PMID:29051433
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Temporal variation and regional transfer of heavy metals in the Pearl (Zhujiang) River, China.
Zhen, Gengchong; Li, Ying; Tong, Yindong; Yang, Lei; Zhu, Yan; Zhang, Wei
2016-05-01
Heavy metals are highly persistent in water and have a particular significance in ecotoxicology. Heavy metals loading from the Pearl River are likely to cause significant impacts on the environment in the South China Sea and the West Pacific. In this study, using monthly monitoring data from a water quality monitoring campaign during 2006-2012, the temporal variation and spatial transfer of six heavy metals (lead (Pb), copper (Cu), cadmium (Cd), zinc (Zn), arsenic (As), and mercury (Hg)) in the Pearl River were analyzed, and the heavy metal fluxes into the sea were calculated. During this period, the annual heavy metal loads discharged from the Pearl River into the South China Sea were 5.8 (Hg), 471.7 (Pb), 1524.6 (Cu), 3819.6 (Zn), 43.9 (Cd), and 621.9 (As) tons, respectively. The metal fluxes showed a seasonal variation with the maximum fluxes occurring from June to July. There is a close association between metal fluxes and runoff. The analysis of the heavy metal transfer from the upstream to the downstream revealed that the transfer from the upstream accounted for a major portion of the heavy metals in the Pearl River Delta. Therefore, earlier industry relocation efforts in the Pearl River watershed may have limited effect on the water quality improvement in surrounding areas. It is suggested that watershed-based pollution control measures focusing on wastewater discharge in both upstream and downstream areas should be developed and implemented in the future.
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Rezania, Shahabaldin; Taib, Shazwin Mat; Md Din, Mohd Fadhil; Dahalan, Farrah Aini; Kamyab, Hesam
2016-11-15
Environmental pollution specifically water pollution is alarming both in the developed and developing countries. Heavy metal contamination of water resources is a critical issue which adversely affects humans, plants and animals. Phytoremediation is a cost-effective remediation technology which able to treat heavy metal polluted sites. This environmental friendly method has been successfully implemented in constructed wetland (CWs) which is able to restore the aquatic biosystem naturally. Nowadays, many aquatic plant species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate plants i.e. macrophytes. Based on the findings, phytofiltration (rhizofiltration) is the sole method which defined as heavy metals removal from water by aquatic plants. Due to specific morphology and higher growth rate, free-floating plants were more efficient to uptake heavy metals in comparison with submerged and emergent plants. In this review, the potential of wide range of aquatic plant species with main focus on four well known species (hyper-accumulators): Pistia stratiotes, Eicchornia spp., Lemna spp. and Salvinia spp. was investigated. Moreover, we discussed about the history, methods and future prospects in phytoremediation of heavy metals by aquatic plants comprehensively. Copyright © 2016. Published by Elsevier B.V.
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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.
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Pathways of heavy metals contamination and associated human health risk in Ajay River basin, India.
Singh, Umesh Kumar; Kumar, Balwant
2017-05-01
The sources of heavy metals and their loads in the Ajay River were investigated based on the seasonal and spatial variations. To identify variation and pathways of heavy metals, seventy-six water samples were estimated for 2 years at nineteen sampling sites. The multifaceted data were applied to evaluate statistical relation between variables and arithmetic calculation of the indices. Fickling plot suggested that the acidic pollutants do not affect the water quality because all samples lie within the neutral pH range. Further, OC showed significant relation with Fe, Mn, Ni and Co. Compositional analysis identified weathering of rocks, mobility of soil and sediment, atmospheric deposition and numerous anthropogenic inputs as major sources of heavy metals. The mean values of heavy metal pollution index (HPI) and pollution index (PI) were found above the critical index and strong loadings respectively due to higher values of Cd, Pb and Fe. Similarly, assessment of human risk revealed that the high load of Cd, Pb and Fe in water body could harm the population. Majority of the samples showed high concentration of heavy metals as compared to regulatory standard and background values, which suggests that the water is highly contaminated through numerous geogenic and anthropogenic sources. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Bioremediation of Toxic Heavy Metals: A Patent Review.
Verma, Neelam; Sharma, Rajni
2017-01-01
The global industrialization is fulfilling the demands of modern population at the cost of environmental exposure to various contaminants including heavy metals. These heavy metals affect water and soil quality. Moreover, these enter into the food chain and exhibit their lethal effects on the human health even when present at slightly higher concentration than required for normal metabolism. To the worst of their part, the heavy metals may become carcinogenic. Henceforth, the efficient removal of heavy metals is the demand of sustainable development. Remedy: Bioremediation is the 'green' imperative technique for the heavy metal removal without creating secondary metabolites in the ecosystem. The metabolic potential of several bacterial, algal, fungal as well as plant species has the efficiency to exterminate the heavy metals from the contaminated sites. Different strategies like bioaccumulation, biosorption, biotransformation, rhizofilteration, bioextraction and volatilization are employed for removal of heavy metals by the biological species. Bioremediation approach is presenting a splendid alternate for conventional expensive and inefficient methods for the heavy metal removal. The patents granted on the bioremediation of toxic heavy metals are summarized in the present manuscript which supported the applicability of bioremediation technique at commercial scale. However, the implementation of the present information and advanced research are mandatory to further explore the concealed potential of biological species to resume the originality of the environment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Silberman, E.; Cretella, R.F.
1963-01-01
As an introduction to the problems in the industrial production of heavy water, the industrial plants in operation are briefly described, and the causes determining their evolution are discussed. The industrial methods studied in England, France, Germandy, Sweden, Switzerland, India, Egypt, Japan, and O.E.C.E. for the production of D/sub 2/O are summarized. The market for heavy water is discussed. The factors considered in the selection of the production process to be developed for Argentina are given, and the cost of a H/sub 2/S-- H/sub 2/O exchange installation is determined. The cost of such a plant modified for Argentine needs ismore » then analyzed. It is concluded that the combination of the H/ sub 2/SH/sub 2/O process in a single unit with integral energy supply, coupled with the elimination of auxiliary installations, results in a considerable reduction in operation costs and plant investment, as compared with the cost of the process in the U.S. The plandt construction plan is summarized. (J.S.R.)« less
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Heavy Metals and Related Trace Elements.
ERIC Educational Resources Information Center
Leland, Harry V.; And Others
1978-01-01
Presents a literature review of heavy metals and related trace elements in the environment, covering publications of 1976-77. This review includes: (1) trace treatment in natural water and in sediments; and (2) bioaccumulation and toxicity of trace elements. A list of 466 references is presented. (HM)
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Heavy metal pollution in soils of abandoned mining areas (SE, Spain)
NASA Astrophysics Data System (ADS)
Martínez-Sánchez, M. J.; Pérez-Sirvent, C.; Molina, J.; Tudela, M. L.; Navarro, M. C.; García-Lorenzo, M. L.
2009-04-01
Elevated levels of heavy metals can be found in and around disused metalliferous mines due to discharge and dispersion of mine wastes into nearby agricultural soils, food crops and stream systems. Heavy metals contained in the residues from mining and metallurgical operations are often dispersed by wind and/or water after their disposal. These areas have severe erosion problems caused by wind and water runoff in which soil and mine spoil texture, landscape topography and regional and microclimate play an important role. The present study was carried out in the Cabezo Rajao (La Uni
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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.
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NASA Astrophysics Data System (ADS)
Caldas-Alvarez, Alberto; Khodayar, Samiro
2017-04-01
An accurate representation of the devastating heavy precipitation events, that typically strike the western Mediterranean regions by autumn, is still a challenge for current weather prediction models. The misrepresentation of the atmospheric moisture distribution and the convective processes where it plays a role have been pointed out as sources of error in their prediction. Provided the fast variability of water vapour in the atmosphere, an improved representation of its distribution is expected from the Data Assimilation (DA) of very frequent measurements, such is the case of Global Positioning System derived Integrated Water Vapour (GPS-IWV). Moreover, an improved representation of the model physics is expected from the application of the DA on fine-scale model grids. The presented research work aims at assessing the impact of the selective assimilation of GPS-IWV retrievals on the representation of the atmospheric moisture distribution in relation to heavy precipitation in seasonal simulations over the western Mediterranean. COSMO simulations in CLimate Mode (CCLM) are run with two different horizontal resolutions (2.8 km and 7 km) to reproduce the period September 2012 to March 2013, encompassing the Special Observation Period 1 (SOP1) of the Hydrological Cycle in the Mediterranean Experiment (HyMeX). A state-of-art GPS-IWV data set, specially homogenized for the western Mediterranean countries spanning the aforementioned seven month period is selectively assimilated into the model runs with a high frequency (10 minutes). The impact of such assimilation combined with the grid refinement of the model is assessed in the representation of the atmospheric moisture distribution and its influence in the processes leading to deep moist convection and heavy rain. Observational data sets of precipitation obtained with the Climate Prediction Centre MORPHing technique (CMORPH), from the HyMeX rain gauge network as well as the GPS-IWV retrievals are employed to validate
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Stabilization of heavy metals in sludge ceramsite.
Xu, G R; Zou, J L; Li, G B
2010-05-01
This paper attempts to investigate the stabilization behaviours of heavy metals in ceramsite made from wastewater treatment sludge (WWTS) and drinking-water treatment sludge (DWTS). Leaching tests were conducted to find out the effects of sintering temperature, (Fe(2)O(3) + CaO + MgO)/(SiO(2) + Al(2)O(3)) (defined as F/SA ratios), pH, and oxidative condition. Results show that sintering exhibits good binding capacity for Cd, Cr, Cu, and Pb in ceramsite and leaching contents of heavy metals will not change above 1000 degrees C. The main crystalline phases in ceramsite sintered at 1000 degrees C are kyanite, quartz, Na-Ca feldspars, sillimanite, and enstatite. The main compounds of heavy metals are crocoite, chrome oxide, cadmium silicate, and copper oxide. Leaching contents of Cd, Cu, and Pb increase as the F/SA ratios increase. Heavy metals in ceramsite with variation of F/SA ratios are also in same steady forms, which prove that stronger chemical bonds are formed between these heavy metals and the components. Leaching contents of heavy metals decrease as pH increases and increase as H(2)O(2) concentration increases. The results indicate that when subjected to rigorous leaching conditions, the crystalline structures still exhibit good chemical binding capacity for heavy metals. In conclusion, it is environmentally safe to use ceramsite in civil and construction fields. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
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Dabkowski, Erinne R.; Shekar, Kadambari Chandra; Li, Ling; Ribeiro, Rogerio F.; Walsh, Kenneth; Previs, Stephen F.; Sadygov, Rovshan G.; Willard, Belinda; Stanley, William C.
2013-01-01
Traditional proteomics provides static assessment of protein content, but not synthetic rates. Recently, proteome dynamics with heavy water (2H2O) was introduced, where 2H labels amino acids that are incorporated into proteins, and the synthesis rate of individual proteins is calculated using mass isotopomer distribution analysis. We refine this approach with a novel algorithm and rigorous selection criteria that improve the accuracy and precision of the calculation of synthesis rates and use it to measure protein kinetics in spatially distinct cardiac mitochondrial subpopulations. Subsarcolemmal mitochondria (SSM) and interfibrillar mitochondria (IFM) were isolated from adult rats, which were given 2H2O in the drinking water for up to 60 days. Plasma 2H2O and myocardial 2H-enrichment of amino acids were stable throughout the experimental protocol. Multiple tryptic peptides were identified from 28 proteins in both SSM and IFM and showed a time-dependent increase in heavy mass isotopomers that was consistent within a given protein. Mitochondrial protein synthesis was relatively slow (average half-life of 30 days, 2.4% per day). Although the synthesis rates for individual proteins were correlated between IFM and SSM (R2 = 0.84; P < 0.0001), values in IFM were 15% less than SSM (P < 0.001). In conclusion, administration of 2H2O results in stable enrichment of the cardiac precursor amino acid pool, with the use of refined analytical and computational methods coupled with cell fractionation one can measure synthesis rates for cardiac proteins in subcellular compartments in vivo, and protein synthesis is slower in mitochondria located among the myofibrils than in the subsarcolemmal region. PMID:23457012
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Lignin: A sustainable biosorbent for heavy metal adsorption from wastewater, a review
NASA Astrophysics Data System (ADS)
Nasrullah, Asma; Bhat, A. H.; Isa, Mohamed Hasnain
2016-11-01
With the recent advancements in science and technology, environmental pollution is a challenging problem due to increased activities in domestic, industrial, and agricultural sector. These activities have led to the release of various types of micropollutants such as heavy metal ions, organic and inorganic ions (detergents, and dye) etc into ground water which badly affects the ecosystem. Among various types of pollutants, heavy metals are the most reported in the recent decade. Water pollution is the most challenging problem, and needs to be controlled for better and healthy ecosystem which requires a healthy, eco-friendly and cheaper technology. In this context. lignin is abundantly available, cheaper and environmentally friendly. For efficient removal of heavy metals, lignin can be modified chemically or thermally to increased its biosorption capacity. In this review merits of adsorption and demerits of other separation technologies are compared. This paper presents the recent state of research on the efficient utilization of lignin, its modification and its adsorption efficiency for heavy metal removal from wastewater.
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Carbonized waste for the cut-down of environmental pollution with heavy metals
NASA Astrophysics Data System (ADS)
Gmucová, K.; Morvová, M.; Havránek, E.; Kliman, J.; Košinár, I.; Kunecová, D.; Malakhov, A. I.; Anisimov, Yu. S.; Morva, I.; Siváček, I.; Sýkorová, M.; Šatka, A.
2011-07-01
Nowadays, an increasing concern about the treatment and disposal of waters contaminated by toxic heavy metals is noticed. The toxic pollutants must be removed from the sewage water which then is fed back into the materials cycle. Any candidate technology should result in reusable by-products. With this in mind, the aim of the present study is to test a low cost procedure for utilization of the carbonized waste, a product of PET (polyethylene terephthalate) bottles pyrolysis on sand bedding, for this purpose. Both the water present in PET bottles waste and combustion exhaust probably contribute to the conversion of carbon char to activated carbon directly within the pyrolysis oven. Preliminary results, obtained for several heavy metal ions under laboratory conditions are presented and discussed. Adsorption of heavy metals on the carbonized PET waste is tested by both the electrochemical methods and X-ray fluorescence spectrometry. A simple desorption procedure for the regeneration of prepared active carbon is proposed.
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Multiple heavy metal removal using an entomopathogenic fungi Beauveria bassiana.
Gola, Deepak; Dey, Priyadarshini; Bhattacharya, Arghya; Mishra, Abhishek; Malik, Anushree; Namburath, Maneesh; Ahammad, Shaikh Ziauddin
2016-10-01
Towards the development of a potential remediation technology for multiple heavy metals [Zn(II), Cu(II), Cd(II), Cr(VI) and Ni(II)] from contaminated water, present study examined the growth kinetics and heavy metal removal ability of Beauveria bassiana in individual and multi metals. The specific growth rate of B. bassiana varied from 0.025h(-1) to 0.039h(-1) in presence of individual/multi heavy metals. FTIR analysis indicated the involvement of different surface functional groups in biosorption of different metals, while cellular changes in fungus was reflected by various microscopic (SEM, AFM and TEM) analysis. TEM studies proved removal of heavy metals via sorption and accumulation processes, whereas AFM studies revealed increase in cell surface roughness in fungal cells exposed to heavy metals. Present study delivers first report on the mechanism of bioremediation of heavy metals when present individually as well as multi metal mixture by entomopathogenic fungi. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Spatio-temporal impacts of dairy lagoon water reuse on soil: heavy metals and salinity.
Corwin, Dennis L; Ahmad, Hamaad Raza
2015-10-01
Diminishing freshwater resources have brought attention to the reuse of degraded water as a water resource rather than a disposal problem. The spatial impact and sustainability of dairy lagoon water reuse from concentrated animal feeding operations (CAFOs) has not been evaluated at field scale. The objective of this study is to monitor the impact of dairy lagoon water blended with recycled water on a 32 ha field near San Jacinto, CA from 2007 to 2011. Spatial monitoring was based on soil samples collected at locations identified from apparent soil electrical conductivity (ECa) directed sampling. Soil samples were taken at depth increments of 0-0.15, 0.15-0.3, 0.3-0.6, 0.6-0.9, 0.9-1.2, 1.2-1.5, and 1.5-1.8 m at 28 sample sites on 7-11 May 2007 and again on 31 May - 2 June 2011 after 4 years of irrigation with the blended waters. Chemical analyses included salinity (electrical conductivity of the saturation extract, ECe), pHe (pH of the saturation extract), SAR (sodium adsorption ratio), trace elements (As, B, Mo, Se), and heavy metals (Cd, Cu, Mn, Ni, Zn). Results indicate a decrease in mean values of pHe at all depth increments; a decrease in ECe and SAR above a depth of 0.15 m, but an increase below 0.15 m; a decrease in all trace elements except B, which increased throughout the 1.8 m profile; and the accumulation of Cd, Mn, and Ni at all depth increments, while Cu was readily leached from the 1.8 m profile. Zinc showed little change. The results focused concern on the potential long-term agronomic effect of salinity, SAR, and B, and the long-term environmental threat of salinity and Cu to detrimentally impact groundwater. The accumulation of Cd, Mn, and Ni in the soil profile raised concern since it provided a potential future source of metals for leaching. The long-term sustainability of dairy lagoon water reuse hinges on regular monitoring to provide spatial feedback for site-specific management.
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Investigation of Media Effects on Removal of Heavy Metals in Bioretention Cells
NASA Astrophysics Data System (ADS)
Gülbaz, Sezar; Melek Kazezyilmaz-Alhan, Cevza; Copty, Nadim K.
2015-04-01
Heavy metals are the most toxic elements at high concentrations, although some of them such as Cu and Zn are essential to plants, humans, and animals within a limited value. However, some heavy metals, such as Pb, have adverse effects even at low concentrations. Therefore, it is known that the toxic metals such as Zn, Cu and Pb in storm water runoff are serious threat for aquatic organisms. It is very important to control and reduce heavy metal concentration in urban storm water runoff. There are several methods to remove the aforementioned toxic metals such as electrolyte extraction, chemical precipitation, ion-exchange, reverse osmosis, membrane filtration, adsorption, cementation, and electrochemical treatment technologies. However, these methods are highly expensive and hard to implement for treatment of big volumes of water such as storm water. For this purpose, Low Impact Development (LID) Best Management Practices (BMPs) have become popular to collect, infiltrate, and treat toxic metals in storm water runoff in recent years. LID-BMP is a land planning method which is used to manage storm water runoff and improve water quality by reducing contaminant in storm water runoff. Bioretention is an example of LID-BMP application of which usage has recently been started in storm water treatment. Researchers have been investigating the advantages of bioretention systems and this study contributes to these research efforts by seeking for the media effects of bioretention on heavy metal removal. For this purpose, batch sorption experiments were performed to determine the distribution coefficients and retardation factor of copper (Cu), lead (Pb), and zinc (Zn) for bioretention media such as mulch, turf, local or vegetative soil, sand and gravel. Furthermore, sorption reaction kinetics of Cu, Pb and Zn are tested in order to assess the sorption equilibrium time of these metals for 5 bioretention media. The results of sorption test show that turf has higher sorption
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USING BIOPOLYMERS TO REMOVE HEAVY METALS FROM SOIL AND WATER
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...
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NASA Astrophysics Data System (ADS)
Bajabaa, S. A.; Abd El-Naby, H.; Dawood, Y.
2009-12-01
The fate and transport of heavy metals and radioelements in groundwater aquifers in five wadis located in the Al Qunfudhah and Wadi Haliy quadrangles were investigated. These wadis are an important source of water to the Red Sea coastal plain. Copper, zinc and other base-metals mineralization occur at eastern parts of these quadrangles that dominates the water catchments area of these wadis. Water, rock and soil samples were collected from all wadis and they were analyzed for major, trace elements, heavy metals and stable isotopes. The chemical and isotopic results showed active water/rock interaction. The preliminary investigation of the data analyses showed some samples with high heavy metals and uranium contents. Generally, the uranium and heavy metal contents are higher in samples collected from the upstream area of each wadi where the crystalline rocks are exposed and direct contact with the runoff. The uranium contents were as high as 120 ppb in some water samples. These elevated values are mainly due to two factors water rock interaction and concentration through evaporation. It was also observed to have elevated heavy metal contents near mining activates, which suggests that these mining activates are playing an important role in mobilizing the heavy elements and in turn affecting the water quality in these wadis.
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Experimentally Determined Relationship between Extinction and Liquid Water Content.
1981-04-01
throuoh 3c. Each type Yze - ly show, ,i linar ’ela . measure! ant’it Thi ’i -wpe t , s , ss om v , function cf toe ’,c ir ., ’ genera m h 3 mechanically ge...APR 01 0 BRUCE, C W BRUCE, Y P YEE UCLASSIIED ERADCO WASI-TfR-06 5 El EEE~hhETE-E ThE-- ADm2 / ASL-TR-0083 Reports Control Symbol OSD-1366...ATMOSPHERIC SCIENCES LABORATORY ~White Sands Misile Range, NM 88002 NOTICES isclaimers The findings in this r7_port ire not to be construed as an
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Microplastics as vector for heavy metal contamination from the marine environment
NASA Astrophysics Data System (ADS)
Brennecke, Dennis; Duarte, Bernardo; Paiva, Filipa; Caçador, Isabel; Canning-Clode, João
2016-09-01
The permanent presence of microplastics in the marine environment is considered a global threat to several marine animals. Heavy metals and microplastics are typically included in two different classes of pollutants but the interaction between these two stressors is poorly understood. During 14 days of experimental manipulation, we examined the adsorption of two heavy metals, copper (Cu) and zinc (Zn), leached from an antifouling paint to virgin polystyrene (PS) beads and aged polyvinyl chloride (PVC) fragments in seawater. We demonstrated that heavy metals were released from the antifouling paint to the water and both microplastic types adsorbed the two heavy metals. This adsorption kinetics was described using partition coefficients and mathematical models. Partition coefficients between pellets and water ranged between 650 and 850 for Cu on PS and PVC, respectively. The adsorption of Cu was significantly greater in PVC fragments than in PS, probably due to higher surface area and polarity of PVC. Concentrations of Cu and Zn increased significantly on PVC and PS over the course of the experiment with the exception of Zn on PS. As a result, we show a significant interaction between these types of microplastics and heavy metals, which can have implications for marine life and the environment. These results strongly support recent findings where plastics can play a key role as vectors for heavy metal ions in the marine system. Finally, our findings highlight the importance of monitoring marine litter and heavy metals, mainly associated with antifouling paints, particularly in the framework of the Marine Strategy Framework Directive (MSFD).
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Heavy metal pollution and health risk assessment in the Wei River in China.
Yang, Xuefu; Duan, Jinming; Wang, Lei; Li, Wei; Guan, Jianling; Beecham, Simon; Mulcahy, Dennis
2015-03-01
From data collected monthly at 26 monitoring cross sections in the Wei River in the Shaanxi Region of China during the period 2008-2012, the temporal pollution characteristics of heavy metals (Hg, Cd, Cr(VI), Pb, and As) were analyzed based on a heavy metal pollution index (HPI). The monthly HPI values of the five heavy metals in the river fluctuated greatly in 2008 and then declined gradually with time. This general trend of reduction in HPI appears not to have a seasonal variation and most likely resulted from the continued improvement in heavy metal pollution control strategies implemented by local environmental agencies combined with a significant improvement in wastewater treatment capacities. Among the five heavy metals, Cd and Pb were below 0.1 and 3 μg L(-1), respectively, at all the sampling points in the studied areas in the year 2012. The detection rates of As, Hg, and Cr(VI) were in the order of Hg > Cr(VI) > As. Hg, Cr(VI), and As exceeded, in a month of the dry season in 2012, the standard limits for category III surface waters according to the China Environment Quality Standards for Surface Water (CEQSSW). Based on the assessment using the HPI method, the pollution status of these heavy metals in water of the Wei River in the Shaanxi Region was generally at an acceptable level, but exhibited distinctive characteristics between the main stream river and tributaries. Most of the tributaries were more seriously polluted than the main river. A health risk assessment was conducted based on the Human Health Risk Assessment (HHRA) method recommended by the United States Environmental Protection Agency (USEPA). Apart from As, the health risk for the five heavy metals in the region were at acceptable levels for drinking water sources (hazard quotient (HQ) < 1, carcinogenic risk (CR) ranged from 10(-4)-10(-6)) according to the Risk Assessment Guidance for Superfund (RAGS), USEPA. Arsenic was identified as the most important pollutant of concern
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Malassa, Husam; Al-Rimawi, Fuad; Al-Khatib, Mahmoud; Al-Qutob, Mutaz
2014-10-01
Rainwater samples harvested for drinking from the west part of Hebron (south of West Bank in Palestine), the largest city in the West Bank, were analyzed for the content of different trace heavy metals (Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, Cd, Bi, and Pb) by inductively coupled plasma mass spectrometry (ICP-MS). This study was conducted to determine the water quality of harvested rainwater used for drinking of south West Bank (case study, Hebron area). A total of 44 water samples were collected in November 2012 from 44 house cisterns used to collect rainwater from the roofs of houses. The samples were analyzed for their pH, temperature, electrical conductivity, total dissolved solids, and different heavy metal contents. The pH of all water samples was within the US Environmental Protection Agency limits (6.5-8.5), while some water samples were found to exceed the allowed WHO limit for total dissolved solids (TDSs) in drinking water. Results showed that concentrations of the heavy metals vary significantly between the 44 samples. Results also showed that the concentration of five heavy metals (Cr, Mn, Ni, Ag, and Pb) is higher than the WHO limits for these heavy metals in drinking water. Overall, our findings revealed that harvested rainwater used for drinking of this part of south West Bank is contaminated with heavy metals that might affect human health.
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2007-03-01
Contaminant Concentrations in Storm Water Entering the Sinclair/Dyes Inlet Subasin of the Puget Sound , USA During Storm Event and Baseflow Conditions...Johnston1 (Space and Naval Warfare Systems Center, Bremerton, WA, USA), Dwight E. Leisle, Bruce Beckwith, and Gerald Sherrell ( Puget Sound Naval Shipyard...The Sinclair and Dyes Inlet watershed is located on the west side of Puget Sound in Kitsap County, Washington, U.S.A. (Figure 1). Puget Sound Naval
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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.
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Amin, Noor-ul; Hussain, Anwar; Alamzeb, Sidra; Begum, Shumaila
2013-02-15
Green vegetable crops irrigated with wastewater are highly contaminated with heavy metals and are the main source of human exposure to the contaminants. In this study accumulation of eight heavy metals (Cu, Ni, Zn, Cr, Fe, Mn, Co and Pb) in green vegetables like Allium cepa, Allium sativum, Solanum lycopersicum and Solanum melongena, irrigated with wastewater in Mardan are studied using Atomic Absorption spectrophotometer. The studied metals in vegetable grown on wastewater irrigated soil were significantly higher than those of tube well water irrigated soil and WHO/FAO permissible limits (P<0.05). The most heavily contaminated vegetable was wastewater irrigated A. cepa, where the accumulation of Mn (28.05 mg kg(-1)) in the edible parts was 50-fold greater than A. cepa irrigated with tube well water irrigated soil. It may be concluded that both adults and children consuming these vegetables grown in wastewater irrigated soil ingest significant amount of these metals and thus can cause serious health problems. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Moore, J W; Sutherland, D J
1981-01-01
The concentrations of heavy metals and radionuclides in the sediments and water of Great Bear Lake were determined during 1978 near an operating silver mine and an abandoned uranium mine. Additional information on the level of mercury in fish tissues were also collected. The mines, situated on the same site, deposited tailings and other waste material directly into the lake. The concentrations of mercury, lead, manganese, and nickel in the sediments were highest near the tailings deposit and decreased significantly as the distance from the mine increased. Although there were also significant positive correlations between these metals and the organic content of the sediments, water depth and slope of the bottom had no impact on metal distribution. Since the concentrations of arsenic, cobalt, copper, 226radium, 210lead and 230thorium varied inconsistently throughout the study area, the distribution of these substances could not be related to any of the environmental factors that were measured. There were, however, significant negative correlations between the concentrations of 232thorium and 228thorium and distance from the mine and organic content of the sediments. Heavy metal and radionuclide levels in water were generally below detectable limits, reflecting the strong chemical bonding characteristics of the sediments. The low concentrations of mercury in the tissues of lake trout Salvelinus namaycush were probably related to low uptake rates and the ability of this species to move into uncontaminated areas of the lake.
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Hydrostatic force used to handle outsized, heavy objects
NASA Technical Reports Server (NTRS)
Craft, G. W.; Starkey, A. W.
1967-01-01
Specially fitted barge is used to load and transport large, heavy objects to a dock side site. There the barge itself can lift, rotate, and position the objects. Typical functions are economically accomplished by water buoyancy.
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Triboelectrification-Enabled Self-Powered Detection and Removal of Heavy Metal Ions in Wastewater.
Li, Zhaoling; Chen, Jun; Guo, Hengyu; Fan, Xing; Wen, Zhen; Yeh, Min-Hsin; Yu, Chongwen; Cao, Xia; Wang, Zhong Lin
2016-04-20
A fundamentally new working principle into the field of self-powered heavy-metal-ion detection and removal using the triboelectrification effect is introduced. The as-developed tribo-nanosensors can selectively detect common heavy metal ions. The water-driven triboelectric nanogenerator is taken as a sustainable power source for heavy-metal-ion removal by recycling the kinetic energy from flowing wastewater. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Heavy metal pollution in immobile and mobile components of lentic ecosystems-a review.
Meena, Ramakrishnan Anu Alias; Sathishkumar, Palanivel; Ameen, Fuad; Yusoff, Abdull Rahim Mohd; Gu, Feng Long
2018-02-01
With growing population and urbanization, there is an increasing exploitation of natural resources, and this often results to environmental pollution. In this review, the levels of heavy metal in lentic compartments (water, sediment, fishes, and aquatic plants) over the past two decades (1997-2017) have been summarized to evaluate the current pollution status of this ecosystem. In all the compartments, the heavy metals dominated are zinc followed by iron. The major reason could be area mineralogy and lithogenic sources. Enormous quantity of metals like iron in estuarine sediment is a very natural incident due to the permanently reducing condition of organic substances. Contamination of cadmium, lead, and chromium was closely associated with anthropogenic origin. In addition, surrounding land use and atmospheric deposition could have been responsible for substantial pollution. The accumulation of heavy metals in fishes and aquatic plants is the result of time-dependent deposition in lentic ecosystems. Moreover, various potential risk assessment methods for heavy metals were discussed. This review concludes that natural phenomena dominate the accumulation of essential heavy metals in lentic ecosystems compared to anthropogenic sources. Amongst other recent reviews on heavy metals from other parts of the world, the present review is executed in such a way that it explains the presence of heavy metals not only in water environment, but also in the whole of the lentic system comprising sediment, fishes, and aquatic plants.
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Fei, Jiang-Chi; Min, Xiao-Bo; Wang, Zhen-Xing; Pang, Zhi-Hua; Liang, Yan-Jie; Ke, Yong
2017-12-01
In recent years, international research on the toxicity of the heavy metal, antimony, has gradually changed focus from early medical and pharmacological toxicology to environmental toxicology and ecotoxicology. However, little research has been conducted for sources identification and risk management of heavy metals pollution by long-term antimony mining activities. In this study, a large number of investigations were conducted on the temporal and spatial distribution of antimony and related heavy metal contaminants (lead, zinc, and arsenic), as well as on the exposure risks for the population for the Yuxi river basin in the Hunan province, China. The scope of the investigations included mine water, waste rock, tailings, agricultural soil, surface water, river sediments, and groundwater sources of drinking water. Health and ecological risks from exposure to heavy metal pollution were evaluated. The main pollution sources of heavy metals in the Yuxi River basin were analyzed. Remediation programs and risk management strategies for heavy metal pollution were consequently proposed. This article provides a scientific basis for the risk assessment and management of heavy metal pollution caused by antimony basin ore mining.
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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.
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Characterizing heavy metal build-up on urban road surfaces: implication for stormwater reuse.
Liu, An; Liu, Liang; Li, Dunzhu; Guan, Yuntao
2015-05-15
Stormwater reuse is increasingly popular in the worldwide. In terms of urban road stormwater, it commonly contains toxic pollutants such as heavy metals, which could undermine the reuse safety. The research study investigated heavy metal build-up characteristics on urban roads in a typical megacity of South China. The research outcomes show the high variability in heavy metal build-up loads among different urban road sites. The degree of traffic congestion and road surface roughness was found to exert a more significant influence on heavy metal build-up rather than traffic volume. Due to relatively higher heavy metal loads, stormwater from roads with more congested traffic conditions or rougher surfaces might be suitable for low-water-quality required activities while the stormwater from by-pass road sections could be appropriate for relatively high-water-quality required purposes since the stormwater could be relatively less polluted. Based on the research outcomes, a decision-making process for heavy metals based urban road stormwater reuse was proposed. The new finding highlights the importance to undertaking a "fit-for-purpose" road stormwater reuse strategy. Additionally, the research results can also contribute to enhancing stormwater reuse safety. Copyright © 2015 Elsevier B.V. All rights reserved.
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Xu, Wang; Ren, Changliang; Teoh, Chai Lean; Peng, Juanjuan; Gadre, Shubhankar Haribhau; Rhee, Hyun-Woo; Lee, Chi-Lik Ken; Chang, Young-Tae
2014-09-02
Herein, a small-molecule fluorescent sensor array for rapid identification of seven heavy metal ions was designed and synthesized, with its sensing mechanism mimicking that of a tongue. The photoinduced electron transfer and intramolecular charge transfer mechanism result in combinatorial interactions between sensor array and heavy metal ions, which lead to diversified fluorescence wavelength shifts and emission intensity changes. Upon principle component analysis (PCA), this result renders clear identification of each heavy metal ion on a 3D spatial dispersion graph. Further exploration provides a concentration-dependent pattern, allowing both qualitative and quantitative measurements of heavy metal ions. On the basis of this information, a "safe-zone" concept was proposed, which provides rapid exclusion of versatile hazardous species from clean water samples based on toxicity characteristic leaching procedure standards. This type of small-molecule fluorescent sensor array could open a new avenue for multiple heavy metal ion detection and simplified water quality analysis.
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Chelate-Assisted Heavy Metal Movement Through the Root Zone
NASA Astrophysics Data System (ADS)
Kirkham, M.; Madrid, F.; Liphadzi, M. S.
2001-12-01
Chelating agents are added to soil as a means to mobilize heavy metals for plant uptake during phytoremediation. Yet almost no studies follow the displacement of heavy metals through the vadose zone following solubilization with chelating agents. The objective of this work was to determine the movement of heavy metals through the soil profile and their absorption by barley (Hordeum vulgare L.) in a soil amended with biosolids and in the presence of a chelating agent (EDTA). Twelve columns 75 cm in height and 17 in diameter were packed with a Haynie very fine sandy loam (coarse-silty, mixed, calcareous, mesic Mollic Udifluvents) and watered with liquid biosolids applied at the surface at a rate of 120 kg N/ha. Three weeks after plants germinated, soil was irrigated with a solution of the disodium salt of EDTA added at a rate of 0.5 g/kg soil. Four treatments were imposed: columns with no plants and no EDTA; columns with no plants plus EDTA; columns with plants and no EDTA; and columns with plants and EDTA. Columns were watered intensively for 35 days until two pore volumes of water had been added, and the leachates were collected daily. With or without plants, columns with EDTA had lower total concentrations of Cu, Zn, Cd, Ni, and Pb in the surface 20 cm than columns without EDTA. Concentrations of the heavy metals in this layer were not afffected by the presence of roots. Iron in leachate was followed as an indicator metal for movement to groundwater. No iron appeared in the leachate without EDTA, either in the columns with plants or without plants. The peak concentration of iron in the leachate occurred three days earlier in the columns without plants and EDTA compared to the columns with plants and EDTA. The results indicated the importance of vegetation on retarding heavy metal leaching to groundwater during chelate-facilitated phytoremediation.
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Polat, Fatih; Akın, Şenol; Yıldırım, Alper; Dal, Tarık
2016-08-01
In this study, the association between heavy metals in water and cyprinids sampled from the Yeşilırmak River stretch, which is frequently exposed to pollutant sources (a sugar production factory (Turhal) and solid wastes dump area (Taşlıçiftlik) was explored, and the oxidative effects of heavy metals on cyprinids were evaluated through analyzing some liver enzymes, namely, superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and cortisol. The heavy metal concentrations of both fish and water, collected from three different locations along the river during the summer of 2011 and winter of 2010 (Turhal, Taşlıçiftlik, and Gümenek), were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The water and fish liver heavy metal concentrations exhibited increasing trends from upstream (Gümenek) to downstream (Turhal). The water and liver samples collected during the summer had higher heavy metal concentrations than those obtained during the winter. The mean heavy metal concentrations increased from Gümenek to Turhal. The liver heavy metal concentrations were higher than those in the water and exhibited almost the same increasing trend from Gümenek to Turhal. Positive relationships between liver and water heavy metal concentrations, especially for cadmium (R 2 = 0.91) and lead (R 2 = 0.98), were obtained. Among the liver enzymes, only MDA followed the same increasing trend from Gümenek to Turhal as was obtained for heavy metals. On the other hand, CAT and SOD had a contrary spatial pattern of change to those of heavy metals and MDA. Although the values of heavy metals and MDA in Taşlıçiftlik were between the two other locations, fish inhabiting this locality had significantly higher values of cortisol, which is an indication of the other stress-causing factors for fish. © The Author(s) 2015.
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Heavy metal contamination in the vicinity of an industrial area near Bucharest.
Velea, Teodor; Gherghe, Liliana; Predica, Vasile; Krebs, Rolf
2009-08-01
Heavy metals such as lead are well known to cause harmful health effects. Especially children are particularly susceptible to increased levels of lead in their blood. It is also a fact that lead concentration is increasing in the environment due to increased anthropogenic activity. The risk of heavy metal contamination is pronounced in the environment adjacent to large industrial complexes. In a combined case study, the environmental pollution by heavy metals was related to children's health in the vicinity of an industrial area located 4 km south-east from Bucharest about 2 km east from the nearest town-Pantelimon. This site includes companies processing different, nonferrous solid wastes for recovery of heavy metals and producing different nonferrous alloys and lead batteries. In this paper, mainly the results of environmental sampling and analyses are summarized. Water, soil, and atmospheric deposition samples were collected from different locations within 3 km from the industrial area. For comparison, samples were also taken from Bucharest. Water samples were filtered (<0.45 microm), extracted by salpetric acid, and quantified by ICP-OES and ICP-MS. Soil samples were dried, sieved (<2 mm), extracted by aqua regia and analyzed by AAS. In order to quantify the atmospheric deposition, three kinds of permanently open collecting pots were used on nine different sites between August and November 2006. At most sampling locations, the heavy metal concentrations in soil decrease with increasing distance to the presumably major source of pollution. Highest heavy metal concentrations were found in 10-20 cm soil depths. There were also decreasing heavy metal concentrations for atmospheric deposition with increasing distance to the industrial site. In surface and groundwater samples, traces of zinc, copper and lead were detected. The heavy metal concentrations in soil were increased in the study area, mostly under legal action limits in low-concern areas (e.g., 1,000 mg Pb
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Li, Ruili; Chai, Minwei; Qiu, Guo Yu
2016-01-01
Overlying water, sediment, rhizosphere sediment and mangrove seedlings in the Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest.
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Li, Ruili; Chai, Minwei; Qiu, Guo Yu
2016-01-01
Overlying water, sediment, rhizosphere sediment and mangrove seedlings in the Futian mangrove forest were analyzed for heavy metals. The results showed that mangrove plant acidified sediment and increased organic matter contents. Except for chromium (Cr), nickel (Ni) and copper (Cu) in Aegiceras corniculatum sediment, heavy metals in all sediments were higher than in overlying water, rhizosphere sediment and mangrove root. Heavy metals in Avicennia marina sediments were higher than other sediments. The lower heavy metal biological concentration factors (BCFs) and translocation factors (TFs) indicated that mangrove plant adopted exclusion strategy. The geo-accumulation index, potential ecological risk index and risk assessment code (RAC) demonstrated that heavy metals have posed a considerable ecological risk, especially for cadmium (Cd). Heavy metals (Cr, Ni, Cu and Cd) mainly existed in the reducible fractions. These findings provide actual heavy metal accumulations in sediment-plant ecosystems in mangrove forest, being important in designing the long-term management and conservation policies for managers of mangrove forest. PMID:26800267
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Meng, Qingpeng; Zhang, Jing; Zhang, Zhaoyu; Wu, Tairan
2016-04-01
Dissolved trace elements and heavy metals in the Dan River drainage basin, which is the drinking water source area of South-to-North Water Transfer Project (China), affect large numbers of people and should therefore be carefully monitored. To investigate the distribution, sources, and quality of river water, this study integrating catchment geology and multivariate statistical techniques was carried out in the Dan River drainage from 99 river water samples collected in 2013. The distribution of trace metal concentrations in the Dan River drainage was similar to that in the Danjiangkou Reservoir, indicating that the reservoir was significantly affected by the Dan River drainage. Moreover, our results suggested that As, Sb, Cd, Mn, and Ni were the major pollutants. We revealed extremely high concentrations of As and Sb in the Laoguan River, Cd in the Qingyou River, Mn, Ni, and Cd in the Yinhua River, As and Sb in the Laojun River, and Sb in the Dan River. According to the water quality index, water in the Dan River drainage was suitable for drinking; however, an exposure risk assessment model suggests that As and Sb in the Laojun and Laoguan rivers could pose a high risk to humans in terms of adverse health and potential non-carcinogenic effects.
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Cloning of a heavy-metal-binding protein derived from activated-sludge microorganisms.
Sano, Daisuke; Myojo, Ken; Omura, Tatsuo
2006-09-01
A gene of the heavy-metal-binding protein (HMBP) was newly isolated from a genetic DNA library of activated-sludge microorganisms. HMBP was produced by transformed Escherichia coli, and the copper-binding ability of HMBP was confirmed. HMBP derived from activated sludge could be available as heavy metal adsorbents in water and wastewater treatments.
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Kang, Joo-Hyon; Lee, Seung Won; Cho, Kyung Hwa; Ki, Seo Jin; Cha, Sung Min; Kim, Joon Ha
2010-07-01
This study reveals land-use factors that explain stream water quality during wet and dry weather conditions in a large river basin using two different linear models-multiple linear regression (MLR) models and constrained least squares (CLS) models. Six land-use types and three topographical parameters (size, slope, and permeability) of the watershed were incorporated into the models as explanatory variables. The suggested models were then demonstrated using a digitized elevation map in conjunction with the land-use and the measured concentration data for Escherichia coli (EC), Enterococci bacteria (ENT), and six heavy metal species collected monthly during 2007-2008 at 50 monitoring sites in the Yeongsan Watershed, Korea. The results showed that the MLR models can be a powerful tool for predicting the average concentrations of pollutants in stream water (the Nash-Sutcliffe (NS) model efficiency coefficients ranged from 0.67 to 0.95). On the other hand, the CLS models, with moderately good prediction performance (the NS coefficients ranged 0.28-0.85), were more suitable for quantifying contributions of respective land-uses to the stream water quality. The CLS models suggested that industrial and urban land-uses are major contributors to the stream concentrations of EC and ENT, whereas agricultural, industrial, and mining areas were significant sources of many heavy metal species. In addition, the slope, size, and permeability of the watershed were found to be important factors determining the extent of the contribution from each land-use type to the stream water quality. The models proposed in this paper can be considered useful tools for developing land cover guidelines and for prioritizing locations for implementing management practices to maintain stream water quality standard in a large river basin. Copyright 2010 Elsevier Ltd. All rights reserved.
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Small angle neutron scattering study of the gemini nonionic surfactant in heavy water solutions
NASA Astrophysics Data System (ADS)
Rajewska, A.
2012-03-01
The nonionic gemini surfactant α α'-[2,4,7,9-tetramethyl-5-decyne-4,7diyl]bis[ω hydroxyl-polyoxyethylene] (S-10) was investigated in heavy water solutions only for concentrations: 2.3%, 2.5%,3%, 3.4%, 4% and 5% at temperature 25°C with small angle neutron scattering (SANS) method. All of surfactants solutions were prepared using D2O (99.9% deuterated, Prikladnaia Chimia, St. Petersburg, Russia) as a solvent. The nonionic gemini surfactant S-10 was obtained from Air Products & Chemicals, Inc., and used without further purification. All SANS measurements were performed on V-4 SANS spectrometer at BENSC, Berlin (Germany). Neutrons were used in wavelength range of 0.02 - 4 nm-1. For the measurements quartz cells of were used during experiment. Up to 14 such cells were placed in a holder. Results from experiment was calculated and evaluated with PCG 2.0 program from Graz University (Austria). In the investigated solutions two axis ellipsoidal micelles was observed.
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Bioaccumulation of heavy metals by freshwater algal species of Bhavnagar, Gujarat, India.
Jaiswar, Santial; Kazi, Mudassar Anisoddin; Mehta, Shailesh
2015-11-01
The present study investigated copper, cadmium, lead and zinc accumulation in algal species Oedogonium, Cladophora, Oscillatoria and Spirogyra from freshwater habitats of Bhavnagar, India. Eight different locations were periodically sampled during August 2009 to March 2011. The general trend of heavy metal concentrations in all the algal species in present study (except at few stations), were found to be in the following order: Zn > Cu > Pb > Cd. Highest accumulation of Cu was recorded in Oedogonium, while Cladophora showed highest accumulation of Pb signifying a good bioaccumulator. Oscillatoria and Oedogonium were highest Zn accumulating algae which showed significant difference between the means at P < 0.05. ANOVA was performed for comparing significance mean between the groups and within the group for heavy metals in water. The concentration of heavy metals in water was in the following order: Zn > Cu > Pb > Cd. The present study showed that Oedogonium, Cladophora, Oscillatoria and Spirogyra were excellent bioaccumulator and could be utilized as biomonitoring agents in water bodies receiving waste contaminated by metals.
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Removal of insoluble heavy metal sulfides from water.
Banfalvi, Gaspar
2006-05-01
The necessity of heavy metal removal from wastewater has led to increasing interest in absorbents. We have developed a new approach to obtain high metal adsorption capacity by precipitating metal sulfides with sodium sulfide on the surface of bentonite and adhere them to the absorbent. This method allowed to remove approximately 90% of cadmium as CdS from 10(-4)-10(-6) M CdCl2 solutions. Additional reactions are related to the removal of excess sodium sulfide by the release of hydrogen sulfide and oxidation to sulfur using carbogen gas (5% CO2, 95% O2) followed by aeration.
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Vijayaraghavan, K; Teo, Ting Ting; Balasubramanian, R; Joshi, Umid Man
2009-05-30
The ability of Sargassum sp. to biosorb four metal ions, namely lead, copper, zinc, and manganese from a synthetic multi-solute system and real storm water runoff has been investigated for the first time. Experiments on synthetic multi-solute systems revealed that Sargassum performed well in the biosorption of all four metal ions, with preference towards Pb, followed by Cu, Zn, and Mn. The solution pH strongly affected the metal biosorption, with pH 6 being identified as the optimal condition for achieving maximum biosorption. Experiments at different biosorbent dosages revealed that good biosorption capacity as well as high metal removal efficiency was observed at 3g/L. The biosorption kinetics was found to be fast with equilibrium being attained within 50 min. According to the Langmuir isotherm model, Sargassum exhibited maximum uptakes of 214, 67.5, 24.2 and 20.2mg/g for lead, copper, zinc, and manganese, respectively in single-solute systems. In multi-metal systems, strong competition between four metal ions in terms of occupancy binding sites was observed, and Sargassum showed preference in the order of Pb>Cu>Zn>Mn. The application of Sargassum to remove four heavy metal ions in real storm water runoff revealed that the biomass was capable of removing the heavy metal ions. However, the biosorption performance was slightly lower compared to that of synthetic metal solutions. Several factors were responsible for this difference, and the most important factor is the presence of other contaminants such as anions, organics, and other trace metals in the runoff.
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Shih, Tsung-Ting; Hsu, I-Hsiang; Chen, Shun-Niang; Chen, Ping-Hung; Deng, Ming-Jay; Chen, Yu; Lin, Yang-Wei; Sun, Yuh-Chang
2015-01-21
We employed a polymeric material, poly(methyl methacrylate) (PMMA), for fabricating a microdevice and then implanted the chlorine (Cl)-containing solid-phase extraction (SPE) functionality into the PMMA chip to develop an innovative on-chip dipole-assisted SPE technique. Instead of the ion-ion interactions utilized in on-chip SPE techniques, the dipole-ion interactions between the highly electronegative C-Cl moieties in the channel interior and the positively charged metal ions were employed to facilitate the on-chip SPE procedures. Furthermore, to avoid labor-intensive manual manipulation, a programmable valve manifold was designed as an interface combining the dipole-assisted SPE microchip and inductively coupled plasma-mass spectrometry (ICP-MS) to achieve the fully automated operation. Under the optimized operation conditions for the established system, the detection limits for each analyte ion were obtained based on three times the standard deviation of seven measurements of the blank eluent solution. The limits ranged from 3.48 to 20.68 ng L(-1), suggesting that this technique appears uniquely suited for determining the levels of heavy metal ions in natural water. Indeed, a series of validation procedures demonstrated that the developed method could be satisfactorily applied to the determination of trace heavy metals in natural water. Remarkably, the developed device was durable enough to be reused more than 160 times without any loss in its analytical performance. To the best of our knowledge, this is the first study reporting on the combination of a dipole-assisted SPE microchip and elemental analysis instrument for the online determination of trace heavy metal ions.
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Karlsson, Kristin; Viklander, Maria; Scholes, Lian; Revitt, Mike
2010-06-15
Sedimentation is a widely used technique in structural best management practices to remove pollutants from stormwater. However, concerns have been expressed about the environmental impacts that may be exerted by the trapped pollutants. This study has concentrated on stormwater ponds and sedimentation tanks and reports on the accumulated metal concentrations (Cd, Cr, Ni, Pb, and Zn) and the associated toxicity to the bacteria Vibrio fischeri. The metal concentrations are compared with guidelines and the toxicity results are assessed in relation to samples for which metal concentrations either exceed or conform to these values. The water phase metal concentrations were highest in the ponds whereas the sedimentation tanks exhibited a distinct decrease towards the outlet. However, none of the water samples demonstrated toxicity even though the concentrations of Cu, Pb, and Zn exceeded the threshold values for the compared guidelines. The facilities with higher traffic intensities had elevated sediment concentrations of Cr, Cu, Ni, and Zn which increased towards the outlet for the sedimentation tanks in agreement with the highest percentage of fine particles. The sediments in both treatment facilities exhibited the expected toxic responses in line with their affinity for heavy metals but the role of organic carbon content is highlighted. Copyright 2010 Elsevier B.V. All rights reserved.
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Swain, Ratnakar; Sahoo, Bhabagrahi
2017-05-01
For river water quality monitoring at 30m × 1-day spatio-temporal scales, a spatial and temporal adaptive reflectance fusion model (STARFM) is developed for estimating turbidity (T u ), total suspended solid (TSS), and six heavy metals (HV) of iron, zinc, copper, chromium, lead and cadmium, by blending the Moderate-Resolution Imaging Spectroradiometer (MODIS) and Landsat (L s ) spectral bands. A combination of regression analysis and genetic algorithm (GA) techniques are applied to develop spectral relationships between T u -L s , TSS-T u , and each HV-TSS. The STARFM algorithm and all the developed relationship models are evaluated satisfactorily by various performance evaluation measures to develop heavy metal pollution index-based vulnerability maps at 1-km resolution in the Brahmani River in eastern India. The Monte-Carlo simulation based analysis of the developed formulations reveals that the uncertainty in estimating Zn and Cd is the minimum (1.04%) and the maximum (5.05%), respectively. Hence, the remote sensing based approach developed herein can effectively be used in many world rivers for real-time monitoring of heavy metal pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Propagation of heavy baryons in heavy-ion collisions
NASA Astrophysics Data System (ADS)
Das, Santosh K.; Torres-Rincon, Juan M.; Tolos, Laura; Minissale, Vincenzo; Scardina, Francesco; Greco, Vincenzo
2016-12-01
The drag and diffusion coefficients of heavy baryons (Λc and Λb ) in the hadronic phase created in the latter stage of the heavy-ion collisions at RHIC and LHC energies have been evaluated recently. In this work we compute some experimental observables, such as the nuclear suppression factor RA A and the elliptic flow v2 of heavy baryons at RHIC and LHC energies, highlighting the role of the hadronic phase contribution to these observables, which are going to be measured at Run 3 of LHC. For the time evolution of the heavy quarks in the quark and gluon plasma (QGP) and heavy baryons in the hadronic phase, we use the Langevin dynamics. For the hadronization of the heavy quarks to heavy baryons we employ Peterson fragmentation functions. We observe a strong suppression of both the Λc and Λb . We find that the hadronic medium has a sizable impact on the heavy-baryon elliptic flow whereas the impact of hadronic medium rescattering is almost unnoticeable on the nuclear suppression factor. We evaluate the Λc/D ratio at RHIC and LHC. We find that the Λc/D ratio remains unaffected due to the hadronic phase rescattering which enables it as a nobel probe of QGP phase dynamics along with its hadronization.
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Analysis of Piping Systems for Life Extension of Heavy Water Plants in India
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mishra, Rajesh K.; Soni, R.S.; Kushwaha, H.S.
Heavy water production in India has achieved many milestones in the past. Two of the successfully running heavy water plants are on the verge of completion of their design life in the near future. One of these two plants, situated at Kota, is a hydrogen sulfide based plant and the other one at Tuticorin is an ammonia-based plant. Various exercises have been planned with an aim to assess the fatigue usage for the various components of these plants in order to extend their life. Considering the process parameters and the past history of the plant performance, critical piping systems andmore » equipment are identified. Analyses have been carried out for these critical piping systems for mainly two kinds of loading, viz. sustained loads and the expansion loads. Static analysis has been carried out to find the induced stress levels due to sustained as well as thermal expansion loading as per the design code ANSI B31.3. Due consideration has been given to the design corrosion allowance while evaluating the stresses due to sustained loads. At the locations where the induced stresses (S{sub L}) due to the sustained loads are exceeding the allowable limits (S{sub h}), exercises have been carried out considering the reduced corrosion allowance value. This strategy is adopted in view of the fact that the thickness measurements carried out at site at various critical locations show a very low rate of corrosion. It has been possible to qualify the system with reduced corrosion allowance values however, it is recommended to keep that location under periodic monitoring. The strategy adopted for carrying out analysis for thermal expansion loading is to qualify the system as per the code allowable value (S{sub a}). If the stresses are more than the allowable value, credit of liberal allowable value as suggested in the code i.e., with the addition of the term (S{sub h}-S{sub L}) to the term 0.25 S{sub h}, has been taken. However, if at any location, it is found that thermal stress
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NASA Astrophysics Data System (ADS)
Wei, W., Sr.; Ma, R.; Sun, Z.; Bu, J.; Chang, Q.
2017-12-01
The head water regions of Heihe River were located in the Qilian orogenic belt, where belongs to the Qilian Mountains National Ecological Nature Protection and has fragile ecosystem. Previous surveys show that the regions were rich in various metal ores, and the mining activities have been intense.The environmental effect of mining activities will be going on several years, while Our field investigation show that there were 23 mines, of which 18 have been historical. This study collected water samples in main Heihe river and its tributaries, groundwaters and soil water, and the sediment samples near the ores. The concentration of HMs in both waters and sediments was measured for characterizing the spatial distribution of HMs, and determining the origin of the HMs in the river waters. Results of water quality assessment show that 67% of water samples failed to reach the Grade II environmental quality standard for surface water in China (GB3838-2002).The spatial distribution of HMs (Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb) is highly correlated with the geographical distribution of local mines, suggesting that various heavy metals(HMs) were released into the Heihe River via mining activities. The Be, Co, Sn, Bi, Th, U were mainly derived from aluminosilicate weathering crusts. And the acid mine wastewater was the main source for Cu, Zn, Pb, Cd. The Serpentine wreathing was the main source for Cr and Ni. Mn and Cs were enriched by agricultural activities.
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NASA Astrophysics Data System (ADS)
Rochaddi, Baskoro; Adhi Suryono, Chrisna; Atmodjo, Warsito; Satriadi, Alfi
2018-02-01
The present study was conducted to assess the level of pesticide and heavy metal contamination in shallow aquifer of Semarang coastal areas. Results indicated that Heptachlor and Arsenic were detected in the water samples in the range 0.023-0.055 μg L-1 and 0,03-1,63 μg L-1, respectively. Compared to the standard limits of the organochlorine contents in the water sample by World Health Organization (WHO) limits and Indonesian Drinking and Domestic Water Quality Standard for Ground Water (IWQS), groundwater of Semarang Coastal Areas was contaminated with pesticide and heavy metal. This study has proven the presence of organochlorine and heavy metal contamination of some shallow aquifer supplies in the coastal areas of Semarang.
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Zhai, Yunbo; Liu, Xiangmin; Zhu, Yun; Peng, Chuan; Wang, Tengfei; Zhu, Luo; Li, Caiting; Zeng, Guangming
2016-10-01
In this study, the effect of feed-water pH (pH=2-12) on fate and risk of heavy metals (HMs) in hydrochars (HCs) was investigated. Hydrothermal carbonization (HTC) of sewage sludge (SS) was carried out with different feed-water pH at 270°C. The research results showed that changing feed-water pH had a positive effect on accumulating Pb, Ni, Cd and Zn in HCs. Chemical forms of Cu and Cr converted from an unstable state to stable in the alkaline environment while in the acidic condition was opposite. The effect of feed-water pH on the chemical forms of HMs was variable but not significant. Risk assessments of Igeo, Er(i), RAC and RI were applied to evaluate the accumulation levels of individual metal, the potential ecological risks, the bio-availabilities and the comprehensive toxicity and sensitivity of HMs, respectively. The lowest pollution level of HMs was obtained at 270°C with pH=11. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Interactions between plant hormones and heavy metals responses.
Bücker-Neto, Lauro; Paiva, Ana Luiza Sobral; Machado, Ronei Dorneles; Arenhart, Rafael Augusto; Margis-Pinheiro, Marcia
2017-01-01
Heavy metals are natural non-biodegradable constituents of the Earth's crust that accumulate and persist indefinitely in the ecosystem as a result of human activities. Since the industrial revolution, the concentration of cadmium, arsenic, lead, mercury and zinc, amongst others, have increasingly contaminated soil and water resources, leading to significant yield losses in plants. These issues have become an important concern of scientific interest. Understanding the molecular and physiological responses of plants to heavy metal stress is critical in order to maximize their productivity. Recent research has extended our view of how plant hormones can regulate and integrate growth responses to various environmental cues in order to sustain life. In the present review we discuss current knowledge about the role of the plant growth hormones abscisic acid, auxin, brassinosteroid and ethylene in signaling pathways, defense mechanisms and alleviation of heavy metal toxicity.
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Nezis, Ioannis P; Shravage, Bhupendra V; Sagona, Antonia P; Johansen, Terje; Baehrecke, Eric H; Stenmark, Harald
2010-11-01
Autophagy has been reported to contribute to cell death, but the underlying mechanisms remain largely unknown and controversial. We have: been studying oogenesis in Drosophila melanogaster as a model system to understand the interplay between autophagy and cell death. Using a novel autophagy reporter we found that autophagy occurs during developmental cell death of nurse cells in late oogenesis. Genetic inhibition: of autophagy-related genes atg1, atg13 and vps34 results in late-stage egg chambers containing persisting nurse cell nuclei without fragmented DNA and attenuation of caspase-3 cleavage. We found that Drosophila inhibitor of apoptosis dBruce is degraded by autophagy and this degradation promotes DNA fragmentation and subsequent nurse cell death. These studies demonstrate that autophagic degradation of an inhibitor: of apoptosis is a novel mechanism of triggering cell death.
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Oligopeptide-heavy metal interaction monitoring by hybrid gold nanoparticle based assay.
Politi, Jane; Spadavecchia, Jolanda; Iodice, Mario; de Stefano, Luca
2015-01-07
Phytochelatins are small peptides that can be found in several organisms, which use these oligopeptides to handle heavy metal elements. Here, we report a method for monitoring interactions between lead(ii) ions in aqueous solutions and phytochelatin 6 oligopeptide bioconjugated onto pegylated gold nanorods (PEG-AuNrs). This study is the first step towards a high sensitive label free optical biosensor to quantify heavy metal pollution in water.
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Assessment of heavy metals in seawater and fish tissues at Pulau Indah, Selangor, Malaysia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Md Yunus, Sabarina, E-mail: sabarina2020@salam.uitm.edu.m; Hamzah, Zaini; Wood, Ab. Khalik
This study focuses on the levels of heavy metals in seawater and selected fish tissue at Pulau Indah, Selangor, Malaysia. Pulau Indah primarily contains Westport (Malaysia’s major port), and a host of full scales factories. Therefore, it is important to monitor the levels of pollution in this water body and the aquatic organisms in the long term effects, due to the human activities in this area. Water samples in this study were taken from 8 locations along the coastal area. The water samples were collected using water sampler and sampling locations were determined using a Global Positioning system (GPS). Similarly,more » in situ water quality parameters including temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using portable multi probes meter. Then, the samples were acidified until pH 2 and filtered. Fish samples were purchased from local fisherman along the Pulau Indah coastal area and samples were digested using concentrated nitric acid in wet digestion method. The levels of selected heavy metals in four species of fish and seawater from Pulau Indah coastal area were determined using Inductive Coupled Plasma Mass Spectrometer (ICPMS) after dilution to the samples. In general, the quality of water at Pulau Indah is lower than Malaysia Marine Water Quality Standard except for few locations were higher than the maximum permissible levels. The concentration of heavy metals which are lead (Pb), copper (Cu), zinc (Zn) and uranium (U) in water samples are in the range of 0.36-5.43 µg/L, 75.20-621.58 µg/L, 11.92-30.52 µg/L, and 4.00-4.65 µg/L respectively. While the results of the four selected fish showed the following order of abundance Zn> U> Cu> Pb. Transfer factor (TF) of heavy metals in fish tissue of selected fish species from the water was discussed. However, the observed metal concentration in the sample tissue did not exceed the allowable limit of Malaysian Food Act (1983) and
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Assessment of heavy metals in seawater and fish tissues at Pulau Indah, Selangor, Malaysia
NASA Astrophysics Data System (ADS)
Md Yunus, Sabarina; Hamzah, Zaini; Wood, Ab. Khalik; Ahmad
2015-04-01
This study focuses on the levels of heavy metals in seawater and selected fish tissue at Pulau Indah, Selangor, Malaysia. Pulau Indah primarily contains Westport (Malaysia's major port), and a host of full scales factories. Therefore, it is important to monitor the levels of pollution in this water body and the aquatic organisms in the long term effects, due to the human activities in this area. Water samples in this study were taken from 8 locations along the coastal area. The water samples were collected using water sampler and sampling locations were determined using a Global Positioning system (GPS). Similarly, in situ water quality parameters including temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using portable multi probes meter. Then, the samples were acidified until pH 2 and filtered. Fish samples were purchased from local fisherman along the Pulau Indah coastal area and samples were digested using concentrated nitric acid in wet digestion method. The levels of selected heavy metals in four species of fish and seawater from Pulau Indah coastal area were determined using Inductive Coupled Plasma Mass Spectrometer (ICPMS) after dilution to the samples. In general, the quality of water at Pulau Indah is lower than Malaysia Marine Water Quality Standard except for few locations were higher than the maximum permissible levels. The concentration of heavy metals which are lead (Pb), copper (Cu), zinc (Zn) and uranium (U) in water samples are in the range of 0.36-5.43 µg/L, 75.20-621.58 µg/L, 11.92-30.52 µg/L, and 4.00-4.65 µg/L respectively. While the results of the four selected fish showed the following order of abundance Zn> U> Cu> Pb. Transfer factor (TF) of heavy metals in fish tissue of selected fish species from the water was discussed. However, the observed metal concentration in the sample tissue did not exceed the allowable limit of Malaysian Food Act (1983) and Regulation (1985
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Heavy winter precipitation in southwest Arizona
NASA Astrophysics Data System (ADS)
Guttman, Nathaniel B.; Lee, Jung Jin; Wallis, James R.
During December 1992, according to the Weekly Climate Bulletin of the Climate Analysis Center in Washington, D.C., heavy precipitation inundated parts of Arizona causing more than 400% of normal precipitation to fall in the southwestern part of the state. Heavy precipitation continued to fall during the next 2 months, causing extensive flooding along the Gila River.Phoenix Weather Service Forecast Office monthly storm data reports indicated flooding along the Santa Cruz and San Pedro Rivers on December 29. From January 7 to 20, roads, bridges, homes, businesses, and farmland suffered considerable flood damage from Graham County westward to Yuma County as rivers and streams swelled. Several thousand people were isolated in their homes as flood waters cut off roads. The January storm data report shows that the combination of a northward-displaced subtropical jet stream, with its abundant moisture supply and associated low pressure disturbances and a southward-displaced polar jet stream, with its storm track, led to the abnormally wet period from late December to mid-January. In February, severe flooding was reported in several areas as water rose in the Painted Rock Reservoir; water accumulating behind the dam produced the largest lake in the state. After exceeding the 2.5 million acre-feet capacity of the reservoir, water began spilling over the dam and damaging homes, crops, farmland, roads, and bridges. About 3,500 residents were evacuated, and the National Guard responded to the flooding with various relief efforts including helicopter support operations. The U.S. and Arizona Departments of Agriculture reported flood damage in excess of $50 million.
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Meng, Qingpeng; Chen, Hong; Lin, Junzhong; Lin, Zhang; Sun, Junliang
2017-06-01
High quality zeolite A was synthesized through a hydrothermal process using alkaline-assisted pre-activated halloysite mineral as the alumina and silica source. The synthesis conditions employed in this study were finely tuned by varying the activating temperature, sodium hydroxide content, water content and Si/Al ratio. The obtained zeolite A showed excellent adsorption properties for both single metal cation solutions and mixed cation solutions when the concentrations of the mixed cations were comparable with those in polluted natural river water and industrial wastewater. High adsorptive capacities for Ag + (123.05mg/g) and Pb 2+ (227.70mg/g) were achieved using the synthesized zeolite A. This observation indicates that the zeolite A synthesized from alkaline-assisted pre-activated halloysite can be used as a low-cost and relatively effective adsorbent to purify heavy metal cation polluted natural river water and industrial wastewater. Copyright © 2016. Published by Elsevier B.V.
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Process for removing heavy metal compounds from heavy crude oil
Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.
1991-01-01
A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.
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Plasma polymer-functionalized silica particles for heavy metals removal.
Akhavan, Behnam; Jarvis, Karyn; Majewski, Peter
2015-02-25
Highly negatively charged particles were fabricated via an innovative plasma-assisted approach for the removal of heavy metal ions. Thiophene plasma polymerization was used to deposit sulfur-rich films onto silica particles followed by the introduction of oxidized sulfur functionalities, such as sulfonate and sulfonic acid, via water-plasma treatments. Surface chemistry analyses were conducted by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy. Electrokinetic measurements quantified the zeta potentials and isoelectric points (IEPs) of modified particles and indicated significant decreases of zeta potentials and IEPs upon plasma modification of particles. Plasma polymerized thiophene-coated particles treated with water plasma for 10 min exhibited an IEP of less than 3.5. The effectiveness of developed surfaces in the adsorption of heavy metal ions was demonstrated through copper (Cu) and zinc (Zn) removal experiments. The removal of metal ions was examined through changing initial pH of solution, removal time, and mass of particles. Increasing the water plasma treatment time to 20 min significantly increased the metal removal efficiency (MRE) of modified particles, whereas further increasing the plasma treatment time reduced the MRE due to the influence of an ablation mechanism. The developed particulate surfaces were capable of removing more than 96.7% of both Cu and Zn ions in 1 h. The combination of plasma polymerization and oxidative plasma treatment is an effective method for the fabrication of new adsorbents for the removal of heavy metals.
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Elimination of cadmium trace contaminations from drinking water.
Zhao, Xuan; Höll, Wolfgang H; Yun, Guichun
2002-02-01
Raw waters polluted with trace heavy metals present serious problems to the part of the Chinese water supply. One of the important contaminants is cadmium. Removal of trace amounts of heavy metals can be achieved by means of selective sorption processes. One of the possibilities is the application of weak base anion exchangers. LEWIS-base/acid interactions lead to an exclusive sorption of heavy metal cations and an equivalent amount of anions of strong acids. The respective elimination of cadmium from pure solutions and spiked natural water and the regeneration of the exhausted exchanger has been investigated. The results demonstrate a very efficient elimination. The standards for drinking water are met for a very large relative volume of treated water. In addition, even a considerable share of dissolved organic matter is adsorbed. Regeneration requires a first step with sulfuric acid to remove the metals and a second one with sodium hydroxide to neutralize the exchanger and to displace the DOC adsorbed. The heavy metals can be concentrated in a small volume which facilitates the discharge of the waste.
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The risk assessment of heavy metals in the ecosystem of urban creeks.
Komínková, D; Nabelková, J
2006-01-01
This paper is focused on risk assessment of heavy metals in freshwater ecosystems of urban creeks. The paper reports changes in an aquatic ecosystem leading to remobilization of heavy metals and consequently to changes of bioavailability. Concentrations of metals in water, bed sediment and benthic organisms from several small urban streams are monitored and evaluated. In the small urban streams studied copper, zinc and lead were determined as the most significant hazard metals. Although concentrations of these metals in water are very low (often below the detection limit of analytical equipment), concentrations in sediment were found in risky levels mainly in sampling sites affected by CSOs and SSOs from industrial and heavy traffic areas. The benthic organisms showed different ability to accumulate heavy metals (HM). The feeding type collector gatherer had in most cases the highest body concentration of HM and the predator species cumulate, to a high level, only zinc which has a high tendency to release from sediment, hence it is the most bio-available. The collector-filterer had mostly low values. The differences among species are due to the different feeding habits of each trophic level.
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Soil quality changes in response to their pollution by heavy metals, Georgia.
Matchavariani, Lia; Kalandadze, Besik; Lagidze, Lamzira; Gokhelashvili, Nino; Sulkhanishvili, Nino; Paichadze, Nino; Dvalashvili, Giorgi
2015-01-01
The present study deals with the composition, migration and accumulation of heavy metals in irrigated soils, plants and partially natural waters; and also, establishing the possible sources of pollution and their impact on environmental situation. The content of toxic elements in the irrigated soils adjacent to ore mining and processing enterprise were studied. Content of toxic elements in the irrigated soils adjacent to ore mining, showed that more than half of territory was seriously polluted by copper and zinc. Some part of the area were considered catastrophically polluted. Expressed technogenesis taking place influenced irrigation. Heavy metals like copper, zinc and manganese negative by effected the properties of soil, thus composition and soil-forming processes taking place in the soil. It was especially well represented in the deterioration of hydro-physical potential of the soil. Irrigation of agricultural land plots by water, polluted with heavy metals changed the pH. Balanced correlation among solid, liquid and gas phases was disrupted. In highly polluted soil, the cementing processes took place that sharply increased the bulk density of the soil, deteriorated the porosity of soil and reduced water permeability critically.
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Mohankumar, K.; Rao, N. Prasada
2016-01-01
Introduction Water is the vital resource, necessary for all aspects of human and ecosystem survival and health. Depending on the quality, bore water may be used for human consumption, irrigation purposes and livestock watering. The quality of bore water can vary widely depending on the quality of ground water that is its source. Pollutants are being added to the ground water system through human and natural processes. Solid waste from industrial units is being dumped near the factories, which react with percolating rainwater and reaches the ground water. The percolating water picks up a large number of heavy metals and reaches the aquifer system and contaminates the ground water. The usage of the contaminated bore water causes the diseases. Mercury, Arsenic and Cadmium are used or released by many industries. Aim This study was conducted to investigate the pollution of bore water in the industrial region (Kurichi Industrial Cluster) of Coimbatore, in the state of Tamilnadu, India. Materials and Methods Four samples were taken from residential areas around Kurichi Industrial Cluster and analysed to find the concentrations of Mercury, Arsenic and Cadmium. Four more samples were taken from other residential regions far from the industrial estate and served as control. Samples were analysed using Atomic absorption spectrophotometry method. Results We found that the ground water of the areas surrounding the industrial cluster does not contain significant amount of those metals. Instead, Heavy metal contamination of ground water were observed in some residential areas of coimbatore. Conclusion The regulatory measures to contain and prevent ground water contamination by industries undertaken by Tamilnadu pollution control board may have lead to absence of heavy metal contamination in Kurichi Industrial cluster, Coimbatore, India. PMID:27190788
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Heavy metal ion removal by thiol functionalized aluminum oxide hydroxide nanowhiskers
NASA Astrophysics Data System (ADS)
Xia, Zhiyong; Baird, Lance; Zimmerman, Natasha; Yeager, Matthew
2017-09-01
In this study, we developed a cost effective method of using thiol functionalized γ-aluminum oxide hydroxide (γ-AlOOH) filters for removing three key heavy metals from water: mercury, lead, and cadmium under non-concomitant conditions. Compared to non-thiol treated γ-AlOOH filters, the introduction of thiol functional groups greatly improved the heavy metal removal efficiency under both static and dynamic filtration conditions. The adsorption kinetics of thiol functionalized γ-AlOOH were investigated using the Lagergren first order and pseudo-second order kinetics models; whereas the isothermal adsorption behavior of these membranes was revealed through the Langmuir and Freundlich models. Heavy metal concentration was quantified by Inductively Coupled Plasma-Mass Spectroscopy, and the thiol level on γ-AlOOH surface was measured by a colorimetric assay using Ellman's reagent. X-ray photoelectron spectroscopy was used to further address the surface sulfur state on the membranes after heavy metal exposure. Mechanisms for heavy metal adsorption were also discussed.
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ERIC Educational Resources Information Center
Onianwa, P. C.
1993-01-01
Reviews research studies related to the monitoring of trace heavy metals in environmental samples such as plants, water, soils, and other natural resources in the city of Ibadan, Nigeria. Research results indicate a significant increase in toxic heavy metal levels has occurred, implying the need for environmental education. (Contains 31…
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Major inorganic elements in tap water samples in Peninsular Malaysia.
Azrina, A; Khoo, H E; Idris, M A; Amin, I; Razman, M R
2011-08-01
Quality drinking water should be free from harmful levels of impurities such as heavy metals and other inorganic elements. Samples of tap water collected from 24 locations in Peninsular Malaysia were determined for inorganic element content. Minerals and heavy metals were analysed by spectroscopy methods, while non-metal elements were analysed using test kits. Minerals and heavy metals determined were sodium, magnesium, potassium, calcium, chromium, manganese, iron, nickel, copper, zinc, arsenic, cadmium and lead while the non-metal elements were fluoride, chloride, nitrate and sulphate. Most of the inorganic elements found in the samples were below the maximum permitted levels recommended by inter-national drinking water standard limits, except for iron and manganese. Iron concentration of tap water from one of the locations was higher than the standard limit. In general, tap water from different parts of Peninsular Malaysia had low concentrations of heavy metals and inorganic elements.
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Malar, Srinivasan; Sahi, Shivendra Vikram; Favas, Paulo J C; Venkatachalam, Perumal
2015-03-01
Mercury heavy metal pollution has become an important environmental problem worldwide. Accumulation of mercury ions by plants may disrupt many cellular functions and block normal growth and development. To assess mercury heavy metal toxicity, we performed an experiment focusing on the responses of Eichhornia crassipes to mercury-induced oxidative stress. E. crassipes seedlings were exposed to varying concentrations of mercury to investigate the level of mercury ions accumulation, changes in growth patterns, antioxidant defense mechanisms, and DNA damage under hydroponics system. Results showed that plant growth rate was significantly inhibited (52 %) at 50 mg/L treatment. Accumulation of mercury ion level were 1.99 mg/g dry weight, 1.74 mg/g dry weight, and 1.39 mg/g dry weight in root, leaf, and petiole tissues, respectively. There was a decreasing trend for chlorophyll a, b, and carotenoids with increasing the concentration of mercury ions. Both the ascorbate peroxidase and malondialdehyde contents showed increased trend in leaves and roots up to 30 mg/L mercury treatment and slightly decreased at the higher concentrations. There was a positive correlation between heavy metal dose and superoxide dismutase, catalase, and peroxidase antioxidative enzyme activities which could be used as biomarkers to monitor pollution in E. crassipes. Due to heavy metal stress, some of the normal DNA bands were disappeared and additional bands were amplified compared to the control in the random amplified polymorphic DNA (RAPD) profile. Random amplified polymorphic DNA results indicated that genomic template stability was significantly affected by mercury heavy metal treatment. We concluded that DNA changes determined by random amplified polymorphic DNA assay evolved a useful molecular marker for detection of genotoxic effects of mercury heavy metal contamination in plant species.
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Interactions between plant hormones and heavy metals responses
Bücker-Neto, Lauro; Paiva, Ana Luiza Sobral; Machado, Ronei Dorneles; Arenhart, Rafael Augusto; Margis-Pinheiro, Marcia
2017-01-01
Abstract Heavy metals are natural non-biodegradable constituents of the Earth's crust that accumulate and persist indefinitely in the ecosystem as a result of human activities. Since the industrial revolution, the concentration of cadmium, arsenic, lead, mercury and zinc, amongst others, have increasingly contaminated soil and water resources, leading to significant yield losses in plants. These issues have become an important concern of scientific interest. Understanding the molecular and physiological responses of plants to heavy metal stress is critical in order to maximize their productivity. Recent research has extended our view of how plant hormones can regulate and integrate growth responses to various environmental cues in order to sustain life. In the present review we discuss current knowledge about the role of the plant growth hormones abscisic acid, auxin, brassinosteroid and ethylene in signaling pathways, defense mechanisms and alleviation of heavy metal toxicity. PMID:28399194
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The analysis of heavy metal in leaching liquid of coal
NASA Astrophysics Data System (ADS)
Cao, Hongmei; Li, Guanglou; Zhang, Lu
2018-02-01
In this paper, heavy metals in coal were extracted by pure water to simulate the leaching effect of natural precipitation or artificial rainfall on outdoor storage of coal. The results show that the leaching liquid pH was slightly declining, and Cu, Zn, Pb, Cd were in μg/L level, far less than the hazardous waste identification standard of GB5085.3-2007. It suggests that leaching liquid was less harmful to environment when coal was immersed by big amount of water. In the case of spray or precipitation less, the pH drop was more obvious, leaching of heavy metals more, and the general elution of the initial dissolution of the most obvious. Although the amount of small but more toxic, the relevant management should be alert to its harmful.
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NASA Astrophysics Data System (ADS)
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
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Data of heavy metals in soil and groundwater at Kiwi gardens of Amlash in Guilan Province, Iran.
Naghipour, Dariush; Ashrafi, Seyed Davoud; Taghavi, Kamran
2018-06-01
Data on this paper describe the concentrations of arsenic, cadmium, copper, nickel, lead and zinc in the surface soils and groundwater's of Kiwi gardens and its relation to chemical fertilizers in Amlash city, Guilan Province, in Iran. The results of this study showed that the average concentration of heavy metals in groundwater and soils of the studied areas was less than the national standards of Iran for irrigation water, Dutch MPA for soils (except Cu and Ni) and Canadian MAC for inorganic fertilizers. Considering that after fertilizing to soils used in gardening, the concentration of heavy metals in groundwater and soil can be increased significantly, so that chemical fertilizers can be considered as an effective factor in increasing the amount of heavy metals in water and soil. The results of this research can be used by who concern about water and soil quality related to fertilizing and also can be used by Rural Water and Wastewater Company and Ministry of Jahad Agriculture of Iran.
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ERIC Educational Resources Information Center
Environmental Science and Technology, 1975
1975-01-01
The Second National Conference on Complete WateReuse stressed better planning, management, and use of water. The sessions covered: water reuse and its problems; water's interface with air and land, and modification of these interactions by the imposition of energy; and heavy metals in the environment and methods for their removal. (BT)
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Burgos-Núñez, Saudith; Navarro-Frómeta, Amado; Marrugo-Negrete, José; Enamorado-Montes, Germán; Urango-Cárdenas, Iván
2017-07-15
The concentrations of polycyclic aromatic hydrocarbons and heavy metals were evaluated in shallow sediments, water, fish and seabird samples from the Cispata Bay, Colombia. The heavy metals concentrations in the sediment was in the following order: Cu>Pb>Hg>Cd. The heavy metal concentration was different (p<0.05) in juvenile and adult birds. High concentrations of mercury were registered in the seabird (10.19±4.99mgkg -1 ) and fish (0.67μgg -1 ) samples. The total concentration of polycyclic aromatic hydrocarbons ranged from 7.0-41ngg -1 in sediment, 0.03-0.34ngmL -1 in water samples, 53.24ngg -1 in fish, and 66ngg -1 in seabirds. The high concentrations of heavy metals in seabirds may be explained by their feeding habits. The presence of polycyclic aromatic hydrocarbons in the Cispata Bay may be due to hydrocarbon spills during oil transport at the nearby oil port. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Abolhasani, Jafar; Behbahani, Mohammad
2015-01-01
Solid-phase extraction is one the most useful and efficient techniques for sample preparation, purification, cleanup, preconcentration, and determination of heavy metals at trace levels. In this paper, functionalized MCM-48 nanoporous silica with 1-(2-pyridylazo)-2-naphthol was applied for trace determination of copper, lead, cadmium, and nickel in water and seafood samples. The experimental conditions such as pH, sample and eluent flow rate, type, concentration and volume of the eluent, breakthrough volume, and effect of coexisting ions were optimized for efficient solid-phase extraction of trace heavy metals in different water and seafood samples. The content of solutions containing the mentioned heavy metals was determined by flame atomic absorption spectrometry (FAAS), and the limits of detection were 0.3, 0.4, 0.6, and 0.9 ng mL(-1) for cadmium, copper, nickel, and lead, respectively. Recoveries and precisions were >98.0 and <4%, respectively. The adsorption capacity of the modified nanoporous silica was 178 mg g(-1) for cadmium, 110 mg g(-1) for copper, 98 mg g(-1) for nickel, and 210 mg g(-1) for lead, respectively. The functionalized MCM-48 nanoporous silica with 1-(2-pyridylazo)-2-naphthol was characterized by thermogravimetry analysis (TGA), differential thermal analysis (DTA), transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffraction (XRD), elemental analysis (CHN), and N2 adsorption surface area measurement.
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Forzani, Erica S; Zhang, Haiqian; Chen, Wilfred; Tao, Nongjian
2005-03-01
We have built a high-resolution differential surface plasmon resonance (SPR) sensor for heavy metal ion detection. The sensor surface is divided into a reference and sensing areas, and the difference in the SPR angles from the two areas is detected with a quadrant cell photodetector as a differential signal. In the presence of metal ions, the differential signal changes due to specific binding of the metal ions onto the sensing area coated with properly selected peptides, which provides an accurate real-time measurement and quantification of the metal ions. Selective detection of Cu2+ and Ni2+ in the ppt-ppb range was achieved by coating the sensing surface with peptides NH2-Gly-Gly-His-COOH and NH2-(His)6-COOH. Cu2+ in drinking water was tested using this sensor.
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Sorption interactions of heavy metals with biochar in soil remediation studies
NASA Astrophysics Data System (ADS)
Fristak, Vladimir; Friesl-Hanl, Wolfgang; Wawra, Anna; Soja, Gerhard
2015-04-01
The search for new materials in soil remediation applications has led to new conversion technologies such as carbonization and pyrolysis. Biochar represents the pyrolytic product of different biomass input materials processed at 350-1000°C and anoxic conditions. The pyrolysis temperature and feedstock have a considerable influence on the quality of the charred product and also its main physico-chemical properties. Biochar as porous material with large specific surface and C-stability is utilized in various environmental and agricultural technologies. Carbon sequestration, increase of soil water-holding capacity and pH as well as sorption of different xenobiotics present only a fraction of the multitude of biochar application possibilities. Heavy metals as potential sources of ecotoxicological risks are characterized by their non-degradability and the potential transfer into the food chain. Carbonaceous materials have been used for a long time as sorbents for heavy metals and organic contaminants in soil and water technologies. The similarity of biochar with activated carbon predetermines this material as remediation tool which plays an important role in heavy metal immobilization and retention with a parallel reduction in the risk of ground water and food crop contamination. In all this processes the element-specific sorption behaviour of biochar creates new conditions for pollutant binding. Sorption interaction and separation of contaminants from soil solution or waste effluent can be affected by wide-ranging parameters. In detail, our study was based on batch-sorption comparisons of two biochars produced from wood chips and green waste residues. We observed that sorption efficiency of biochar for model bivalent heavy metals (Cd, Zn, Cu) can be influenced by equilibrium parameters such as pH, contact time, initial concentration of metal in reaction solutions, presence of surfactants and chemical modification by acid hydrolysis, esterification and methylation. The
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Heavy metal immobilization via microbially induced carbonate precipitation and co-precipitation
NASA Astrophysics Data System (ADS)
Lauchnor, E. G.; Stoick, E.
2017-12-01
Microbially induced CaCO3 precipitation (MICP) has been successfully used in applications such as porous media consolidation and sealing of leakage pathways in the subsurface, and it has the potential to be used for remediation of metal and radionuclide contaminants in surface and groundwater. In this work, MICP is investigated for removal of dissolved heavy metals from contaminated mine discharge water via co-precipitation in CaCO3 or formation of other metal carbonates. The bacterially catalyzed hydrolysis of urea produces inorganic carbon and ammonium and increases pH and the saturation index of carbonate minerals to promote precipitation of CaCO3. Other heavy metal cations can be co-precipitated in CaCO3 as impurities or by replacing Ca2+ in the crystal lattice. We performed laboratory batch experiments of MICP in alkaline mine drainage sampled from an abandoned mine site in Montana and containing a mixture of heavy metals at near neutral pH. Both a model bacterium, Sporosarcina pasteurii, and a ureolytic bacterium isolated from sediments on the mine site were used to promote MICP. Removal of dissolved metals from the aqueous phase was determined via inductively coupled plasma mass spectrometry and resulting precipitates were analyzed via electron microscopy and energy dispersive x-ray spectroscopy (EDX). Both S. pasteurii and the native ureolytic isolate demonstrated ureolysis, increased the pH and promoted precipitation of CaCO3 in batch tests. MICP by the native bacterium reduced concentrations of the heavy metals zinc, copper, cadmium, nickel and manganese in the water. S. pasteurii was also able to promote MICP, but with less removal of dissolved metals. Analysis of precipitates revealed calcium carbonate and phosphate minerals were likely present. The native isolate is undergoing identification via 16S DNA sequencing. Ongoing work will evaluate biofilm formation and MICP by the isolate in continuous flow, gravel-filled laboratory columns. This research
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Chemical changes in heavy metals in the leachates from Technosols.
Yao, F X; Macías, F; Virgel, S; Blanco, F; Jiang, X; Camps Arbestain, M
2009-09-01
A 2 month long column study was conducted to evaluate the mobility of heavy metals eluting from Technosols constituted from sewage sludges (aerobic or anaerobic) (as controls) or a mixture of different types of sewage sludges with green foundry sand (FS) or/and Linz-Donowitz slag (LD). The organic and inorganic wastes were mixed at a ratio of 56:44 (w/w). The mixtures and the controls were moistened to field capacity before adding them to the polypropylene columns (4.5 cm wide and 14 cm long). During the 8-week experimental period, the columns were watered, twice a week, with 100 mL of deionised water. The concentrations of heavy metals (Cu, Zn, Ni, Pb, Cd, and Cr) in the leachates were determined periodically. The concentrations of all the heavy metals were generally higher in the leachates from the Technosols containing anaerobic sewage sludge as a component. The concentration of Cu was strongly dependent on pH and was significantly higher (P<0.05) in the most alkaline leachates (pH>10) than in the other leachates. More Zn was mobilized in the most acidic leachates (pH<6) than in other leachates. The concentration of Ni in 80% of the leachates exceeded the EU drinking water limit for Ni (0.02 mgL(-1)). The concentrations of Pb were lower in the Technosols containing FS. The concentrations of Cd in the leachates from Technosols containing the conditioners were relatively high, while concentrations of Cr were higher in the controls. As far as the potential toxicity of heavy metals is concerned, the combination of aerobic sludge, inorganic conditioners able to buffer the pH to around neutrality, and reactive aluminosilicates, can be regarded as suitable choice for formulating Technosols from wastes.
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Sano, D; Myojo, K; Omura, T
2006-01-01
Water pollution with toxic heavy metals is of growing concern because heavy metals could bring about serious problems for not only ecosystems in the water environment but also human health. Some metal removal technologies have been in practical use, but much energy and troublesome treatments for chemical wastes are required to operate these conventional technologies. In this study, heavy metal-binding proteins (HMBPs) were obtained from metal-stimulated activated sludge culture with affinity chromatography using copper ion as a ligand. Two-dimensional electrophoresis revealed that a number of proteins in activated sludge culture were recovered as HMBPs for copper ion. N-termini of five HMBPs were determined, and two of them were found to be newly discovered proteins for which no amino acid sequences in protein databases were retrieved at more than 80% identities. Metal-coordinating amino acids occupied 38% of residues in one of the N-terminal sequences of the newly discovered HMBPs. Since these HMBPs were expected to be stable under conditions of water and wastewater treatments, it would be possible to utilize HMBPs as novel adsorbents for heavy metal removal if mass volume of HMBPs can be obtained with protein cloning techniques.
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Hong, Nian; Zhu, Panfeng; Liu, An
2017-12-01
Urban road stormwater is an alternative water resource to mitigate water shortage issues in the worldwide. Heavy metals deposited (build-up) on urban road surface can enter road stormwater runoff, undermining stormwater reuse safety. As heavy metal build-up loads perform high variabilities in terms of spatial distribution and is strongly influenced by surrounding land uses, it is essential to develop an approach to identify hot-spots where stormwater runoff could include high heavy metal concentrations and hence cannot be reused if it is not properly treated. This study developed a robust modelling approach to estimating heavy metal build-up loads on urban roads using land use fractions (representing percentages of land uses within a given area) by an artificial neural network (ANN) model technique. Based on the modelling results, a series of heavy metal load spatial distribution maps and a comprehensive ecological risk map were generated. These maps provided a visualization platform to identify priority areas where the stormwater can be safely reused. Additionally, these maps can be utilized as an urban land use planning tool in the context of effective stormwater reuse strategy implementation. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Toxicity assessment of heavy metal mixtures by Lemna minor L.
Horvat, Tea; Vidaković-Cifrek, Zeljka; Orescanin, Visnja; Tkalec, Mirta; Pevalek-Kozlina, Branka
2007-10-01
The discharge of untreated electroplating wastewaters directly into the environment is a certain source of heavy metals in surface waters. Even though heavy metal discharge is regulated by environmental laws many small-scale electroplating facilities do not apply adequate protective measures. Electroplating wastewaters contain large amounts of various heavy metals (the composition depending on the facility) and the pH value often bellow 2. Such pollution diminishes the biodiversity of aquatic ecosystems and also endangers human health. The aim of our study was to observe/measure the toxic effects induced by a mixture of seven heavy metals on a bioindicator species Lemna minor L. Since artificial laboratory metal mixtures cannot entirely predict behaviour of metal mixtures nor provide us with informations relating to the specific conditions in the realistic environment we have used an actual electroplating wastewater sample discharged from a small electroplating facility. In order to obtain three more samples with the same composition of heavy metals but at different concentrations, the original electroplating wastewater sample has undergone a purification process. The purification process used was developed by Orescanin et al. [Orescanin V, Mikelić L, Lulić S, Nad K, Rubcić M, Pavlović G. Purification of electroplating wastewaters utilizing waste by-product ferrous sulphate and wood fly ash. J Environ Sci Health A 2004; 39 (9): 2437-2446.] in order to remove the heavy metals and adjust the pH value to acceptable values for discharge into the environment. Studies involving plants and multielemental waters are very rare because of the difficulty in explaining interactions of the combined toxicities. Regardless of the complexity in interpretation, Lemna bioassay can be efficiently used to assess combined effects of multimetal samples. Such realistic samples should not be avoided because they can provide us with a wide range of information which can help explain
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Heavy metal pollution in Tianjin, China—its bioavailability prediction and mitigation practice
NASA Astrophysics Data System (ADS)
Sun, Hongwen; Wang, Ting; Zhang, Yanfeng; Jiang, Chunxiao; Wang, Jing
2010-05-01
Irrigation of sewage water has been applied for agriculture production in Tianjin for over 50 years, for Tianjin is a city lacking water resource. Based on the result of an extensive investigation on heavy metals in the farmland of Tianjin in 2005, 21 samples (including soil and lettuce) were collected from most the polluted areas along the three sewage rivers. Nine of the 21 soil samples exceeded the National Soil Quality Standard for cadmium (0.6 mg/kg) and 7 exceeded the standard for mercury (1.0 mg/kg). However, the heavy metal contents in lettuce did not correlate the heavy metal concentrations in soil. The bioavailability changed with soil properties. The part extracted by diethylene-triaminepentaacetic acid (DTPA) and another mixed extraction solvent, M3, were used to predict the bioavailability of heavy metals. The solvent extraction gave good prediction on Cd absorbance in lettuce, with correlative coefficient larger than 0.9. However, it failed for Hg. This may be because Hg is relatively volatile, and the absorption patterns are complex for Hg. To set up a mitigation method for heavy metal pollution in farm land, friendly to agricultural production, in-situ fixing strategy was adopted. Bacillus subtilis and Candida tropicalis were induced by ultraviolet (UV) radiation and HNO2 treatment to get mutated strains that can tolerate and accumulate higher level of cadmium. A strain of B38 from B. subtilis showed the highest Cd tolerance, and was used for further experiment. Though B38 could accumulate Cd from water solution, but it did not fix Cd in soil. This is due to that the amended microorganisms could not propagate well in the polluted soil. Novogro, which is produced from the waste of an enzyme factory, was selected out from several materials to amend together with B38. After the co-amendment of Novogro and B38, the DTPA extractable Cd decreased by 72%, and B38 could propagate efficiently as indicated by DGGE test. Applying conditions, such as amendment
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Water quality assessment of Australian ports using water quality evaluation indices
Jahan, Sayka
2017-01-01
Australian ports serve diverse and extensive activities, such as shipping, tourism and fisheries, which may all impact the quality of port water. In this work water quality monitoring at different ports using a range of water quality evaluation indices was applied to assess the port water quality. Seawater samples at 30 stations in the year 2016–2017 from six ports in NSW, Australia, namely Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden, were investigated to determine the physicochemical and biological variables that affect the port water quality. The large datasets obtained were designed to determine the Water Quality Index, Heavy metal Evaluation Index, Contamination Index and newly developed Environmental Water Quality Index. The study revealed medium water quality index and high and medium heavy metal evaluation index at three of the study ports and high contamination index in almost all study ports. Low level dissolved oxygen and higher level of total dissolved solids, turbidity, fecal coliforms, copper, iron, lead, zinc, manganese, cadmium and cobalt are mainly responsible for the poor water qualities of the port areas. Good water quality at the background samples indicated that various port activities are the likely cause for poor water quality inside the port area. PMID:29244876
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Zhao, Xin; Li, Ting-Yong; Zhang, Tao-Tao; Luo, Wei-Jun; Li, Jun-Yun
2017-01-01
The Three Gorges Project (TGP) is the largest hydropower station ever built in the world. A better understanding of the concentrations of heavy metals in the aquatic environment of the Three Gorges Reservoir (TGR) is crucial for national drinking water security and sustainable ecosystem development. To thoroughly investigate the impact of heavy metals on water quality after the impoundment to the maximum level of 175 m in the TGR, the concentrations of the dissolved heavy metals (Cr, Cu, Zn, Cd, Pb, As) were measured in April and August 2015, by inductively coupled plasma mass spectrometry (ICP-MS). (1) Except Zn and Pb, most of the heavy metal concentrations in the water of the TGR reached the level of the National Surface Water Environmental Quality Standards (GB3838-2002) I of China, revealing that the water quality of the TGR was good overall. (2) There were significant positive correlations among the concentrations of Cu, As, and Cd, revealing that they may exhibit similar geochemical behaviors. (3) The spatial distribution of the heavy metal concentrations was diverse and complex. The Zn concentration obviously increased in the rainy season from upstream to downstream in the Yangtze River, while the other heavy metals exhibited no significant changes in their concentrations. The distribution characteristics of the heavy metal concentrations on both sides and the middle of the river were different at different sites. (4) The health risk of the six elements was assessed through a human health risk assessment (HHRA), and the assessment results were lower than the maximum acceptable risk level designed by the US EPA and International Commission on Radiological Protection (ICRP). The HHRA model in the aquatic environment revealed that the risk of non-carcinogenic heavy metals (Cu, Zn, and Pb) was at a negligible risk level of 10 -11 ∼10 -9 a -1 . At all the study sites, the risk of carcinogenic heavy metals (Cr, Cd, and As) was higher than the risk of non
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Statistical Analysis Of Heavy Metals Concentration In Watermelon Plants Irrigated By Wastewater
NASA Astrophysics Data System (ADS)
Khanjani, M. J.; Maghsoudi moud, A. A.; Saffari, V. R.; Hashamipor, S. M.; Soltanizadeh, M.
2008-01-01
Concentration of heavy metals in vegetables irrigated by urban wastewater is a cause of serious concern due to the potentials health problems of consuming contaminated produce. In this study it is tried to model the concentration of heavy metals (Cd, Cr, Cu, Fe,…) as a function of their concentration in watermelon roots and stems. Our study shows there is a good relationship between them for most of collected data. By measuring the concentration in root and stem of watermelon plant samples before harvesting, the concentration of heavy metal in watermelon's fruit can be estimated by presented mathematical models. This study shows the concentrations of heavy metals in fruits, roots and stems of watermelon plants are very high and in dangerous level when irrigated by municipal waste water.
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Interior view, looking up toward project west at the heavy ...
Interior view, looking up toward project west at the heavy timber joists and center beam supporting the wood water tank. Note the iron compression bands around the perimeter of the tank. Note also the iron (steel?) water fill pipe for the tank, bent to fit between the joists and the tank wall. - East Broad Top Railroad & Company, Water Tank at Coles Station, East Broad Top Railroad & Company (at Milepost 24.3), 0.5 miles east of Coles Valley Road, Saltillo, Huntingdon County, PA
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NASA Astrophysics Data System (ADS)
Gupta, S.; Nayek, S.; Saha, R. N.; Satpati, S.
2008-08-01
The present study deals with the characterization of effluent released from sponge iron industries and distribution of heavy metals in soil and macrophytes near to effluent discharge channel. Apart from this, accumulation of heavy metals in nearby soil and vegetation system irrigated with effluent-contaminated water is also the subject of this study. Physico-chemical analysis of effluent reveals that the concentration of total suspended solids (TSS), total hardness (TH), iron (Fe2+), and oil and grease are greater than the IS (1981) norms for discharge of water into inland water body. The soil along the sides of the effluent channel also shows higher concentration of heavy metals than the background soil. The enrichment of the heavy metals are in the order of Chromium (Cr) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Copper (Cu) > Cadmium (Cd). Macrophytes growing along the sides of the effluent channel also show significant accumulation of heavy metals almost in the same order as accumulated in soil. Higher uptake of heavy metals by these varieties reveals that these species can be used for future phytoremediation. The effluent as well as contaminated water is extensively used for irrigation for growing vegetables like tomato ( Lycopersicon esculatum) in the surrounding areas. Heavy metal accumulation in this agricultural soil are in the sequence of Cr > Fe > Mn > Zn > Cu > Cd. More or less similar type of accumulation pattern are also found in tomato plants except Fe and Zn exceeding Cr and Mn. Transfer Factor of heavy metals from soil to tomato plants (TFS) shows average value of <1, suggesting less uptake of heavy metals from soil. Among the plant parts studied, fruit shows least accumulation. Although tomato plants show some phenotypic changes, the survival of tomato plants as well as least accumulation of metals in fruit reveals their tolerance to heavy metals. Therefore it may be suggested that this plant can be grown successfully in the heavy metal
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[Beijing common green tree leaves' accumulation capacity for heavy metals].
Li, Shao-Ning; Kong, Ling-Wei; Lu, Shao-Wei; Chen, Bo; Gao, Chen; Shi, Yuan
2014-05-01
Seasonal variation of heavy metal contents in leaves and their relationships with soil heavy metal pollution levels were studied through measuring and analyzing the leaves of the common tree species in Beijing and soil heavy metal contents, to detect heavy metal accumulation ability of plant leaves. The results showed that: (1) the contents of Cu, Pb, Zn in plant leaves first decreased and then increased, again declined with changing the seasons (from spring to winter). Cr concentration showed the trend of first increase and then decrease from spring to winter, and the highest in the autumn; the accumulation capacities of Cu for Babylonica and Japonica were higher in the spring, summer and autumn, while Tabuliformis was in winter; the higher accumulation capacities for Cr, Pb were Japonica and Platycladus, and in winter were Platycladus and Bungeana; the higher accumulation capacities for Zn were Babylonica and Bungeana, while Platycladus in winter; (2) the pollution degree of four kinds of heavy metals (Cu, Cr, Pb, Zn) from downtown to suburbs showed that: Jingshan (C =2.48, C is contamination factor) > Olympic (C = 1.27) > Songshan (C = 1.20) > Shuiguan (C = 1. 18); (3) the heavy metals concentration of same plant leaves in the water of the Great Wall changed larger, but those in the other three areas showed that: Jingshan > Olympic > Songshan; the ability of same species leaf to absorb different sorts of heavy metals showed that: Zn >Cu >Pb >Cr; the difference between Zn content and Cr content was significant (P <0.01); (4) the relationship between heavy metal content in plant leaves and soil heavy metal pollution levels presented a quadratic polynomial relation; the significant correlation was found between other three heavy metal contents of plant samples and soil samples, but they were not the case for the Cu, and the correlation coefficients were above 0. 9.
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HEAVY WATER AS A PARTHENOGENIC AGENT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spindel, W.; Gross, P.R.
1961-10-01
It was found that D/sub 2/O evokes parthenogenic division of eggs stored therein prior to fertilization. When unfertilized sea urchin eggs are stored in 99+% D/sub 2/O-sea water for 1-2 hours, then washed and returned to normal sea water, they cleave, in remarkably high percentages, at about 35 minutes after removal from D/sub 2/O (21 deg C). These are cleavages without benefit of sperm, and they continue for many hours, most cells becoming disorganized blastulae. The first cleavages are always multiple and irregular in such experiments, and the furrowing pattern is closely related to the distribution of the numerous cytastersmore » which remain and grow after removal of the cells from D/sub 2/O. When the period of immersion is shorter, or the concentration of D/sub 2/O reduced, the time required for the appearance of the first parthenogenic cleavages increases rapidly; hence, for a ten-minute storage period, the first cleavage interval is 3-4 hours, and the final yield of divided cells is smaller. Parthenogenesis cannot be produced if the concentration of D/sub 2/O falls to 70% or less. The striking effects of prolonged storage in D/sub 2/O are not results of aging alone, since controls stored for the same intervals in normal sea water do not divide. The effect appears to depend upon the formation of stable cytasters, which begins in 99+% D/sub 2/Osea water after 10 minutes of storage for unfertilized eggs. Thus, eggs stored in D/sub 2/O and then fertilized show normal cleavage in the absence of cytasters, but multiple cleavage when cytasters persist in the cytoplasm after removal of D/sub 2/O. (auth)« less
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Ferati, Flora; Kerolli-Mustafa, Mihone; Kraja-Ylli, Arjana
2015-06-01
The concentrations of As, Cd, Cr, Co, Cu, Ni, Pb, and Zn in water and sediment samples from Trepça and Sitnica rivers were determined to assess the level of contamination. Six water and sediment samples were collected during the period from April to July 2014. Most of the water samples was found within the European and Kosovo permissible limits. The highest concentration of As, Cd, Pb, and Zn originates primarily from anthropogenic sources such discharge of industrial water from mining flotation and from the mine waste eroded from the river banks. Sediment contamination assessment was carried out using the pollution indicators such as contamination factor (CF), degree of contamination (Cd), modified degree of contamination (mCd), pollution load index (PLI), and geo-accumulation index (Igeo). The CF values for the investigated metals indicated a high contaminated nature of sediments, while the Cd values indicated a very high contamination degree of sediments. The mCd values indicate a high degree of contamination of Sitnica river sediment to ultrahigh degree of contamination of Trepça river sediment. The PLI values ranged from 1.89 to 14.1 which indicate that the heavy metal concentration levels in all investigated sites exceeded the background values and sediment quality guidelines. The average values of Igeo revealed the following ranking of intensity of heavy metal contamination of the Trepça and Sitnica river sediments: Cd > As > Pb > Zn > Cu > Co > Cr > Ni. Cluster analysis suggests that As, Cd, Cr, Co, Cu, Ni, Pb, and Zn are derived from anthropogenic sources, particularly discharges from mining flotation and erosion form waste from a zinc mine plant. In order to protect the sediments from further contamination, the designing of a monitoring network and reducing the anthropogenic discharges are suggested.
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VIEW OF PDP AND LTR CONTROL PANEL (LEFT) AND HEAVY ...
VIEW OF PDP AND LTR CONTROL PANEL (LEFT) AND HEAVY WATER CONTROL PANEL (RIGHT) AT SOUTH END OF PDP CONTROL ROOM, LEVEL 0, LOOKING SOUTH - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC
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Bhattacharya, Kakoli; Parasar, Devaborniny; Mondal, Bholanath; Deb, Pritam
2015-01-01
Porous magnetic secondary nanostructures exhibit high surface area because of the presence of plentiful interparticle spaces or pores. Mesoporous Fe3O4 secondary nanostructures (MFSNs) have been studied here as versatile adsorbent for heavy metal scavenging. The porosity combined with magnetic functionality of the secondary nanostructures has facilitated efficient heavy metal (As, Cu and Cd) remediation from water solution within a short period of contact time. It is because of the larger surface area of MFSNs due to the porous network in addition to primary nanostructures which provides abundant adsorption sites facilitating high adsorption of the heavy metal ions. The brilliance of adsorption property of MFSNs has been realized through comprehensive adsorption studies and detailed kinetics. Due to their larger dimension, MFSNs help in overcoming the Brownian motion which facilitates easy separation of the metal ion sorbed secondary nanostructures and also do not get drained out during filtration, thus providing pure water. PMID:26602613
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Shih, Tsung-Ting; Hsieh, Cheng-Chuan; Luo, Yu-Ting; Su, Yi-An; Chen, Ping-Hung; Chuang, Yu-Chen; Sun, Yuh-Chang
2016-04-15
Herein, a hyphenated system combining a high-throughput solid-phase extraction (htSPE) microchip with inductively coupled plasma-mass spectrometry (ICP-MS) for rapid determination of trace heavy metals was developed. Rather than performing multiple analyses in parallel for the enhancement of analytical throughput, we improved the processing speed for individual samples by increasing the operation flow rate during SPE procedures. To this end, an innovative device combining a micromixer and a multi-channeled extraction unit was designed. Furthermore, a programmable valve manifold was used to interface the developed microchip and ICP-MS instrumentation in order to fully automate the system, leading to a dramatic reduction in operation time and human error. Under the optimized operation conditions for the established system, detection limits of 1.64-42.54 ng L(-1) for the analyte ions were achieved. Validation procedures demonstrated that the developed method could be satisfactorily applied to the determination of trace heavy metals in natural water. Each analysis could be readily accomplished within just 186 s using the established system. This represents, to the best of our knowledge, an unprecedented speed for the analysis of trace heavy metal ions. Copyright © 2016 Elsevier B.V. All rights reserved.
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Hydrocolloid liquid-core capsules for the removal of heavy-metal cations from water.
Nussinovitch, A; Dagan, O
2015-12-15
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(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(+2)/g dry alginate vs. 267 mg Pb(+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(2+)), cadmium (Cd(2+)) and nickel (Ni(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 1M nitric acid suspension for 24h. Capsules could undergo three regeneration cycles before becoming damaged. Copyright © 2015 Elsevier B.V. All rights reserved.
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Huang, Xianfei; Hu, Jiwei; Li, Cunxiong; Deng, Jiajun; Long, Jian; Qin, Fanxin
2009-12-01
Baihua Lake, a man-made reservoir, is one of the five drinking water sources for Guiyang City in China's southwestern province of Guizhou. In the present research, the distribution and accumulation characteristics of heavy metals (Pb, Cd, As, Cu and Zn) for the sediment of this lake were analyzed by examination of 10 recently collected samples. A method based on toxic-response factor was applied to assess the potential ecological risk of these heavy metals to the water body. For comparison, the two sets of reference data representing the pre-industrial and the local baseline pollution levels were employed to derive the accumulating coefficients for the heavy metals under study. The calculated potential ecological risk indices show that the lake was polluted by heavy metals and both cadmium and arsenic loadings were critical factors responsible for the ecological hazards posed to Baihua Lake by the five elements.
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Heavy metals content in acid mine drainage at abandoned and active mining area
NASA Astrophysics Data System (ADS)
Hatar, Hazirah; Rahim, Sahibin Abd; Razi, Wan Mohd; Sahrani, Fathul Karim
2013-11-01
This study was conducted at former Barite Mine, Tasik Chini and former iron mine Sungai Lembing in Pahang, and also active gold mine at Lubuk Mandi, Terengganu. This study was conducted to determine heavy metals content in acid mine drainage (AMD) at the study areas. Fourteen water sampling stations within the study area were chosen for this purpose. In situ water characteristic determinations were carried out for pH, electrical conductivity (EC), redox potential (ORP) and total dissolved solid (TDS) using multi parameter YSI 556. Water samples were collected and analysed in the laboratory for sulfate, total acidity and heavy metals which follow the standard methods of APHA (1999) and HACH (2003). Heavy metals in the water samples were determined directly using Inductive Coupled Plasma Mass Spectrometry (ICP-MS). Data obtained showed a highly acidic mean of pH values with pH ranged from 2.6 ± 0.3 to 3.2 ± 0.2. Mean of electrical conductivity ranged from 0.57 ± 0.25 to 1.01 ± 0.70 mS/cm. Redox potential mean ranged from 487.40 ± 13.68 to 579.9 ± 80.46 mV. Mean of total dissolved solids (TDS) in AMD ranged from 306.50 ± 125.16 to 608.14 ± 411.64 mg/L. Mean of sulfate concentration in AMD ranged from 32.33 ± 1.41 to 207.08 ± 85.06 mg/L, whereas the mean of total acidity ranged from 69.17 ± 5.89 to 205.12 ± 170.83 mgCaCO3/L. Heavy metals content in AMD is dominated by Fe, Cu, Mn and Zn with mean concentrations range from 2.16 ± 1.61 to 36.31 ± 41.02 mg/L, 0.17 ± 0.13 to 11.06 ± 2.85 mg/L, 1.12 ± 0.65 to 7.17 ± 6.05 mg/L and 0.62 ± 0.21 to 6.56 ± 4.11 mg/L, respectively. Mean concentrations of Ni, Co, As, Cd and Pb were less than 0.21, 0.51, 0.24, 0.05 and 0.45 mg/L, respectively. Significant correlation occurred between Fe and Mn, Cu, Zn, Co and Cd. Water pH correlated negatively with all the heavy metals, whereas total acidity, sulfate, total dissolved solid, and redox potential correlated positively. The concentration of heavy metals in the AMD
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NASA Astrophysics Data System (ADS)
Dartois, E.; Augé, B.; Boduch, P.; Brunetto, R.; Chabot, M.; Domaracka, A.; Ding, J. J.; Kamalou, O.; Lv, X. Y.; Rothard, H.; da Silveira, E. F.; Thomas, J. C.
2015-04-01
Context. Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. Aims: We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. Methods: We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). Results: The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic stopping power. Conclusions: The final state of cosmic ray irradiation for porous amorphous and crystalline ice, as monitored by infrared spectroscopy, is the same, but with a large difference in cross-section, hence in time scale in an astrophysical context. The cosmic ray water-ice sputtering rates compete with the UV photodesorption yields reported in the literature. The prevalence of direct cosmic ray sputtering over cosmic-ray induced photons photodesorption may be particularly true for ices strongly bonded to the ice mantles surfaces, such as hydrogen-bonded ice structures or more generally the so-called polar ices. Experiments performed at the Grand Accélérateur National d'Ions Lourds (GANIL) Caen, France. Part of this work has been financed by the French INSU-CNRS programme "Physique et Chimie du Milieu Interstellaire" (PCMI) and the ANR IGLIAS.
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Roads as sources of heavy metals in urban areas. The Covões Catchment experiment, Coimbra, Portugal
NASA Astrophysics Data System (ADS)
Ferreira, António J. D.; Soares, Daniel; Ferreira, Carla S. S.; Walsh, Rory P. D.
2015-04-01
Cities are the home to 50% of the human specie [UN 2011 Ramalho & Hobbs 2012], whose wellbeing, way of life and exposure to hazard situations are directly related to the built environment. Cities are often seen as ecological systems just a short step away from collapse [Newman 2006]. Being a human construction, cities disrupt the natural cycles and the patterns of temporal and spatial distribution of environmental and ecological processes. Urbanization produces ruptures in biota, water, energy and nutrients connectivity that can lead to an enhanced exposure to disruptive events that hamper the wellbeing and the resilience of urban communities in a global change context. A major issue in what concerns the threats to human and ecosystem health in urban areas is the presence of heavy metals, and the related processes that govern their source, transport and fade r uptake by the vegetation. In this work, we present an analysis of heavy metal sources and transport processes at various types of roads within the Ribeira dos Covões peri-urban experimental catchment in central Portugal. The surveyed heavy metals (Cadmium, Lead, Coper, and Zinc) show significant differences as a result of the type of rainfall event, the length of the antecedent dry spell, the traffic volume and the heavy metals sources. For some locations, namely for the roads with heavy traffic volume, the heavy metal concentrations exceed the limits established by law, which has severe implications to the downstream ecosystems and to the possible use of the water from roads to close the resources loop in urban areas, namely in what concerns their use to water the urban green infrastructure or to irrigate the urban agriculture fields.
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Abdel-Gaber, Rewaida; Abdel-Ghaffar, Fathy; Abdallah Shazly, Mohamed; Morsy, Kareem; Al Quraishy, Saleh; Mohamed, Sanna; Mehlhorn, Heinz
2017-06-01
Parasites are one of the most serious limiting factors in aquaculture. The Electric catfish Malapterurus electricus was subjected to study the prevalence and mean intensity of parasitic infections throughout the whole year of 2015. Heavy metals accumulation in host fish and parasites were determined in relation to water quality and sediments of two different sites of Lake Manzala (Manzala and Bahr El-Baqar), Egypt. A total of 100 specimens of Electric catfish were collected and examined for the presence of helminth parasites. Two parasite species were recovered and morphologically identified. These were cestoda Electrotaenia malapteruri and nematode Dujardinnascaris malapteruri. Heavy metal analysis in water and sediments showed that measured heavy metals in Bahr El-Baqar were found in risky levels higher than permissible limits and Manzala site. Sediments were found to contain a higher level of metals than water samples. Heavy metals accumulation in recovered parasites and their host were also determined and showed significantly higher concentrations in parasites compared to their host tissues. According to bioconcentration factors, E. malapteruri showed that highest accumulation rate for all recorded elements up to 302. Essential elements like Cu and Fe were found in significantly higher concentrations in D. malapteruri, whereas E. malapteruri accumulated elements Cd, Pb, Ni, Mn, Zn and Ca to a significantly higher degree. Accordingly, the ratios (C[D.malapteruri]/C[E. malapteruri]) for most essential elements were higher than 0.5. Therefore, fish cestodes can be regarded as useful bio-indicators more than nematodes when evaluating the environmental pollution of aquatic ecosystems by heavy metals.
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Antiquarian books as source of environment historical water data.
Schram, Jürgen; Schneider, Mario; Horst, Rasmus; Thieme, Hagen
2009-05-01
Historical environment considerations are inevitable also for modern environmental analysis. They alone allow evaluation of anthropogenic impact into the environment. To receive information about the historical environment situation in inhabited regions, we approached this task by examining historical well dated and locatable products of the Homo faber. The work introduced here uses books as a source of environment historical data specially for the environmental compartment of water. The paper of historical books, dated by their printing and allocated by their watermark(1) (Wasserzeichensammlung Piccard, Piccard online, Hauptstaatsarchiv Stuttgart, ) is a trap for traces of heavy metals contaminating their production water in historical times. Great amounts of water were brought into contact with the paper pulp in the historical paper mill process. The cellulose of the pulp acts as an ion exchange material for heavy metals, forming a dynamic equilibrium. A well defined pulp production process, starting with used clothes, allows estimation of the concentration of historical heavy metals (Cu(2+), Pb(2+), Zn(2+), Cd(2+)) in the production water (river water). Ancient papers from well dated books are eluted without destruction of their paper and the resulting solution is analysed by ETAAS and inverse stripping voltammetry to determine the historical impact of metals. Afterwards in a flow system the eluted paper spot is equilibrated with different concentrations of heavy metals (Cu(2+), Pb(2+), Zn(2+), Cd(2+)) to plot the adsorption isotherm of that very spot. Both data together allows a calculation of the heavy metal content of the historical river. For different waters of Germany and the Netherlands of the 16th-18th Century the heavy metal load could be estimated. The resulting concentrations were mostly similar to the level of modern surface waters, but in the case of the Dutch waters of the 17th Century, they were e.g. for Pb(2+) significantly higher than modern
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Heavy and Heavy-Light Mesons in the Covariant Spectator Theory
NASA Astrophysics Data System (ADS)
Stadler, Alfred; Leitão, Sofia; Peña, M. T.; Biernat, Elmar P.
2018-05-01
The masses and vertex functions of heavy and heavy-light mesons, described as quark-antiquark bound states, are calculated with the Covariant Spectator Theory (CST). We use a kernel with an adjustable mixture of Lorentz scalar, pseudoscalar, and vector linear confining interaction, together with a one-gluon-exchange kernel. A series of fits to the heavy and heavy-light meson spectrum were calculated, and we discuss what conclusions can be drawn from it, especially about the Lorentz structure of the kernel. We also apply the Brodsky-Huang-Lepage prescription to express the CST wave functions for heavy quarkonia in terms of light-front variables. They agree remarkably well with light-front wave functions obtained in the Hamiltonian basis light-front quantization approach, even in excited states.
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Wang, Juan; Liu, Guannan; Wu, Hao; Zhang, Tao; Liu, Xinhui; Li, Wuqing
2018-04-01
The physicochemical properties and heavy metal(loid) concentrations of the river water both fluctuate greatly along the river affected by mining activities, and the transportation of heavy metal(loid)s is therefore more complicated than unpolluted river. Dissolved and particulate heavy metal(loid)s in a river polluted by mining activities were measured to study their temporal-spatial variation and partitioning. The concentrations of dissolved arsenic (As), cadmium (Cd), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were considerably high at the sites near the mine area. Notably, dissolved As at most sites were higher than the Chinese quality criterion of class II for surface water indicating high environmental risk. Mn and Pb at most sites and Ni at a part of the sites mainly existed in the particulate phase. For other heavy metal(loid)s, i.e., As, Cd, chromium (Cr), and Zn, the particulate phase was extremely high at the sites near the mine area and responsible for heavy metal(loid) transport. Significant correlations between particulate heavy metal(loid)s and temperature and electrical conductivity (EC) were found. However, the partitioning of heavy metal(loid)s did not significantly relate to the river water properties, due to most heavy metal(loid)s in suspended particulate matter (SPM) are stable and affected less by water properties. Except for Cr and Ni, other heavy metal(loid)s showed high concentrations in sediments, and considerable Cd, Mn, and Zn existed in exchangeable and carbonate fraction indicating high environmental risk. The environmental assessment of SPM showed that Cd, Zn, and As, as the main pollutants in SPM, all reached extremely polluted level at the sites near the mine area, and the environmental risk of heavy metal(loid)s in SPM was higher during dry season than that during wet season. The results can contribute to understanding the partitioning and transportation of heavy metal(loid)s in the river affected by mining activities.
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NASA Astrophysics Data System (ADS)
Vaibhaw, Kumar; Rao, S. V. R.; Jha, S. K.; Saibaba, N.; Jayaraj, R. N.
2008-12-01
Zircaloy-4 material is used for cladding tube in pressurized heavy water reactors (PHWRs) of 220 MWe and 540 MWe capacity in India. These tubes are fabricated by using various combinations of thermo-mechanical processes to achieve desired mechanical and corrosion properties. Cladding tube develops crystallographic texture during its fabrication, which has significant influence on its in-reactor performance. Due to radiolytic decomposition of water Zircaloy-4 picks-up hydrogen. This hydrogen in excess of its maximum solubility in reactor operating condition (˜300 °C), precipitates as zirconium hydrides causing embrittlement of cladding tube. Hydride orientation in the radial direction of the tube limits the service life and lowers the fuel burn-up in reactor. The orientation of the hydride primarily depends on texture developed during fabrication. A correlation between hydride orientation ( F n) with the texture in the tube during its fabrication has been developed using a second order polynomial. The present work is aimed at quantification and correlation of texture evolved in Zircaloy-4 cladding tube using Kearn's f-parameter during its fabrication process.
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NASA Astrophysics Data System (ADS)
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.
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Carr, M.H.
1986-01-01
Mars had outgassed at least 0.5 to 1 km of water, 10 to 20 bar of CO2, and 0.1 to 0.3 bar of N2. The volatiles that have been retained are mostly in the cratered uplands. Terrain softening, fretted channels, debris flows, and closed depressions indicate that at least the upper 2 km of the cratered uplands at high latitudes (>30??) contain ice in amounts that exceed the porosity, estimated to be 10-20%. Theoretical studies, and lack of these features in the cratered uplands at low latitudes, suggest that the upper 1 km of the uplands at low latitudes is ice poor. However, valley networks indicate that water was present near the surface early in the planet's history, although in amounts smaller than at high latitudes. The entire upper 1 km, planetwide is estimated to have contained 75-125 m of water at the end of heavy bombardment. The largest sink for water is the megaregolith below 1 km. Episodic eruption of water from the deep megaregolith cut many of the large outflow channels. From the volume of water needed to cut the circum-Chryse channels, and assuming uniform planetwide distribution of water, the deep megaregolith is estimated to have contained at least 350 m of water at the end of heavy bombardment, thereby giving a total minimum inventory of 424-475 m planetwide. Most of the water lost from the low-latitude uplands by diffusion and in cutting the valley networks is now believed to be in the polar layered terrains. Most of the water involved in cutting the outflow channels is in the low-lying northern plains where a variety of features that have been attributed to ground ice is present. A large fraction of the planet's surface has been overplated with water-poor volcanics, of which we have samples in the SNC meteorites. The younger volcanics have reacted extensively with the old volatile-rich basement. Some of the CO2 and N2 outgassed was lost during heavy bombardment by impact erosion of the atmosphere and other processes. The remaining was fixed
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Gao, Lei; Chen, Jian-Yao; Ke, Zhi-Ting; Wang, Jiang; Yang, Xue-Yun; Shimizu, Yuta
2013-08-01
Shima River, a tributary of Dongjiang River, located in Dongguan City of Guangdong Province, has been seriously polluted in the last 30 years. Water samples were collected from the river and the aquifer and the soil samples were collected as well in the wet (June) and dry (February) season to investigate the temporal and spatial variations of water quality in terms of heavy metal concentrations and inhibition rate of the luminescent bacterium (Vibrio fischeri, LUMIStox 300). Heavy metal concentrations and inhibition rate in river water were found decreasing from the upstream to the downstream, with metal concentrations exceeding the national surface water quality standard (Class I) for all samples and a highest inhibition of 38.34% (equivalent to moderate toxic) at R1 in the dry season. Significant difference (P < 0.01 or P < 0.001) in the wet and dry season was identified in both metal concentrations and inhibition rate, except at R11, which showed a inhibition rate of 15.56%, higher than those in all other samples in the wet season. Inhibition rate at GW4, GW5 and GW6 showed significant difference (P < 0.01 or P < 0.001) in the two periods, and the highest inhibition rate (15.88%) at GW6 in the dry season was considered as low in toxicity. The positive correlations (P < 0.05 or P < 0.01) between heavy metals (Zn, Fe, Mn and Ni) and inhibition rate were identified with correlation coefficients of 0.452, 0.567, 0.726 and 0.475, respectively. Heavy metal pollution of soil (Cu, Ni and Zn) near the river was due to the interaction between the river and the groundwater. Cd was heavily accumulated in the soil, while elevated concentrations of Fe and Mn were found in the river and the groundwater was heavily polluted by Ni.
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Geochemical and stable isotope characteristics of urban heavy rain in the downtown of Tokyo, Japan
NASA Astrophysics Data System (ADS)
Uchiyama, Ryunosuke; Okochi, Hiroshi; Ogata, Hiroko; Katsumi, Naoya; Asai, Daisuke; Nakano, Takanori
2017-09-01
In order to make clear the impact of air pollution on the formation of sudden and locally-distributed heavy rain in urban area (hereafter Urban Heavy Rain: UHR), we analyzed inorganic ion concentration and stable isotope ratio of water (δD and δ18O) in rainwater. Rainwater samples were collected in Shinjuku, which is a representative downtown of Tokyo, Japan, during four years from October 2012 to December 2015. The concentration and wet deposition fluxes of acidic components (H+, NH4+, NO3-, and nss-SO42 -) in UHR were especially higher than those in other types of rain events, i.e. normal rain, typhoon heavy rain, and frontal heavy rain. UHR had distinctly lower stable isotope ratios than those in other urban rains with same rainfall amount and summer precipitation systems. There was a high negative correlation between δ18O and the distances from the sampling point to the formation area of UHR within 10 km, while there were high positive correlations between δ18O and the concentration of acidic components in UHR. These findings indicate that UHR could effectively scavenge acidic substances within cloud and suggest the use of stable isotope ratios as tracers of an urban heavy rain's water and in-cloud scavenging process.
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Fu, Jie; Zhao, Changpo; Luo, Yupeng; Liu, Chunsheng; Kyzas, George Z; Luo, Yin; Zhao, Dongye; An, Shuqing; Zhu, Hailiang
2014-04-15
This work investigated heavy metal pollution in surface sediments of the Jialu River, China. Sediment samples were collected at 19 sites along the river in connection with field surveys and the total concentrations were determined using atomic fluorescence spectrometer and inductively coupled plasma optical emission spectrometer. Sediment samples with higher metal concentrations were collected from the upper reach of the river, while sediments in the middle and lower reaches had relatively lower metal concentrations. Multivariate techniques including Pearson correlation, hierarchical cluster and principal components analysis were used to evaluate the metal sources. The ecological risk associated with the heavy metals in sediments was rated as moderate based on the assessments using methods of consensus-based Sediment Quality Guidelines, Potential Ecological Risk Index and Geo-accumulation Index. The relations between heavy metals and various environmental factors (i.e., chemical properties of sediments, water quality indices and aquatic organism indices) were also studied. Nitrate nitrogen, total nitrogen, and total polycyclic aromatic hydrocarbons concentrations in sediments showed a co-release behavior with heavy metals. Ammonia nitrogen, total nitrogen, orthophosphate, total phosphate and permanganate index in water were found to be related to metal sedimentation. Heavy metals in sediments posed a potential impact on the benthos community. Copyright © 2014 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Hussain, Athar; Maitra, Jaya; Khan, Kashif Ali
2017-12-01
Heavy metals are usually released into water bodies from industrial/domestic effluents such as metal plating industries, mining and tanneries. Adsorption is a fundamental process in the physiochemical treatment of wastewaters because of its low cost. Great efforts have been made to use the economically efficient and unconventional adsorbents to adsorb heavy metals from aqueous solutions, such as plant wastes and agricultural waste. Biochar mixed with chitosan after crosslinking can be casted into membranes, beads and solutions which can be effectively utilized as an adsorbent for metal ion uptake. Keeping these facts into consideration, the present study was undertaken with the objective to determine the effect of various proportions of biochar-modified chitosan membranes on the sorption characteristics of different heavy metals like Cu, Pb, As and Cd along with comparison of sorption characteristics between industrial waste water samples containing multi-metals and standard synthetic stock solution containing a particular metal. It is apparent from the results that the bioadsorbent prepared from biochar and chitosan are low-cost efficacious resource due to its easy availability. It is also eco-friendly material for making adsorbent for abstraction of heavy metals from aqueous solution. This adsorbent can be best utilized for adsorption of heavy metals.
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Ab Razak, N H; Praveena, S M; Aris, A Z; Hashim, Z
2016-02-01
Information about the quality of drinking water, together with analysis of knowledge, attitude and practice (KAP) analysis and health risk assessment (HRA) remain limited. The aims of this study were: (1) to ascertain the level of KAP regarding heavy metal contamination of drinking water in Pasir Mas; (2) to determine the concentration of heavy metals (Al, Cr, Cu, Fe, Ni, Pb, Zn and Cd) in drinking water in Pasir Mas; and (3) to estimate the health risks (non-carcinogenic and carcinogenic) caused by heavy metal exposure through drinking water using hazard quotient and lifetime cancer risk. Information on KAP was collected using a standardized questionnaire. Heavy metal analysis of drinking water samples was performed using graphite furnace atomic absorption spectrophotometry. The population of Pasir Mas has good knowledge (80%), a less positive attitude (93%) and good practice (81%) towards heavy metal contamination of drinking water. The concentrations of heavy metals analysed in this study were found to be below the permissible limits for drinking water set by the Malaysian Ministry of Health and the World Health Organization. The HRA showed no potential non-carcinogenic and carcinogenic risks from the intake of heavy metal through drinking water. By investigating the quality of drinking water, KAP and HRA, the results of this study will provide authorities with the knowledge and resources to improve the management of drinking water quality in the future. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Zhang, Chunxia; Appel, Erwin; Qiao, Qingqing
2013-03-01
The presence of heavy metals (HMs) in the environment is a major threat for humans. Magnetic proxies provide a rapid method for assessing the degree of HM pollution in environment. We have studied farmland soil irrigated with polluted river water in the vicinity of a steel plant in Loudi city (Hunan Province, China) to test the efficiency of magnetic methods for detecting the degree of HM pollution. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these farmland soils. Enhanced magnetic concentration values were found in the upper arable soil horizon (0-20 cm), which is related to the presence of spherical ˜10 to 30 μm sized magnetite particles. The spatial distribution of magnetic concentration and HM contents in the farmland soils matches with the spatial pattern of these parameters in river sediments. These findings provide evidence that HM pollution of the farmland soil is mainly caused by irrigation with wastewater. HMs Zn, Pb, Cu, Cd, Co, Ni, V are well correlate with magnetic susceptibility (χ). The pollution load index (PLI) of all nine anthropogenic HMs (including also Cr and Mo) and log10(χ) are significantly correlated. Using the resulting linear PLI-log10(χ) function, values of χ can serve as a convenient tool for semi-quantifying the degree of HM pollution in the uppermost ˜20 cm of the studied farmland soils. These findings suggest that magnetic methods can generally serve as a convenient tool for detecting and mapping HM pollution in farmland soil irrigated with wastewater from sites nearby heavy industrial activities.
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[Effects of strong reductive process on transformation of heavy metals in protected vegetable soil].
Sun, Yan Chen; Zeng, Xiang Feng; Yang, Li Qiong; Shi, Ya Nan; Chen, Xi Juan; Zhuang, Jie
2017-11-01
The application of sewage and manure in protected vegetable cultivation can induce the occurrence of heavy metals contamination. The present research studied the transformation of heavy metals (Cd, Cu, Pb and Zn) by incubating contaminated protected soil with maize straw and then leaching. The results showed that soil pH was significantly decreased, being more evident in maize straw treatment; soil Eh dropped quickly below -280 mV. Maize straw treatment promoted the activation of Cd, Cu, Pb and Zn from soil, and the total percent of oxidizable fraction and residual fraction of Cd, Cu, Pb and Zn declined at 9 th day; the amount of Cd, Cu, Pb and Zn in soil reduced 18.1%, 19.0%, 16.1% and 15.7% at 15 th day, respectively. Compared to control, maize straw treatment could increase the concentrations of dissolved Cd and Zn, but Cu decreased. The concentration of colloidal-bound Cd and Pb increased, Cu decreased and no significant change occurred in Zn in maize straw treatment. Strong reductive approach could activate heavy metals in protected vegetable soil, increase the risk of heavy metals accumulation in vegetables, and possibly cause water pollution accompanied with soil water mobilization.
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Characterization of heavy metal desorption from road-deposited sediment under acid rain scenarios.
Zhao, Bo; Liu, An; Wu, Guangxue; Li, Dunzhu; Guan, Yuntao
2017-01-01
Road-deposited sediments (RDS) on urban impervious surfaces are important carriers of heavy metals. Dissolved heavy metals that come from RDS influenced by acid rain, are more harmful to urban receiving water than particulate parts. RDS and its associated heavy metals were investigated at typical functional areas, including industrial, commercial and residential sites, in Guangdong, Southern China, which was an acid rain sensitive area. Total and dissolved heavy metals in five particle size fractions were analyzed using a shaking method under acid rain scenarios. Investigated heavy metals showed no difference in the proportion of dissolved fraction in the solution under different acid rain pHs above 3.0, regardless of land use. Dissolved loading of heavy metals related to organic carbon content were different in runoff from main traffic roads of three land use types. Coarse particles (>150μm) that could be efficiently removed by conventional street sweepers, accounted for 55.1%-47.1% of the total dissolved metal loading in runoff with pH3.0-5.6. The obtained findings provided a significant scientific basis to understand heavy metal release and influence of RDS grain-size distribution and land use in dissolved heavy metal pollution affected by acid rain. Copyright © 2016. Published by Elsevier B.V.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Sawhney, B.L.; Bugbee, G.J.; Stilwell, D.E.
1994-07-01
The leaching of heavy metals in source-separated municipal solid waste (MSW) compost was determined by irrigation leaching of growth medium, admixed with varying amounts of compost, used for container grown plants. Perennial flowers (black-eyed Susan, Rudbeckia hirta L.) were grown in 2-L containers filled with the growth medium for a 10-wk period. Rainfall was supplemented with overhead irrigation to supply 2 cm of water per day. Leachates collected over each 2-wk period were analyzed for Cd, Cr, Cu, Ni, Pb, and Zn using atomic spectrometry. Concentrations of the heavy metals in the leachates increased with increasing proportions of MSW compostmore » in the growth medium, but decreased with time of leaching. Leaching of the metals occurred at relatively high concentrations initially, followed by continued leaching at low concentrations. The initial leaching of heavy metals is attributed to their soluble or exchangeable forms and the subsequent slow leaching to the solid compounds. The concentrations of the heavy metals remained below the current drinking water standards in all treatments throughout the leaching period. The results thus suggest that contamination of groundwater with heavy metals from source-separated MSW compost applied as a soil amendment should be negligible, as the low concentrations in the leachates leaving the surface soil would be further attenuated by the subsoil. 29 refs., 6 figs., 1 tab.« less
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Asgari Lajayer, Behnam; Ghorbanpour, Mansour; Nikabadi, Shahab
2017-11-01
Contamination of soils, water and air with toxic heavy metals by various human activities is a crucial environmental problem in both developing and developed countries. Heavy metals could be introduced into medicinal plant products through contaminated environment (soil, water and air resources) and/or poor production practices. Growing of medicinal plants in heavy metal polluted environments may eventually affect the biosynthesis of secondary metabolites, causing significant changes in the quantity and quality of these compounds. Certain medicinal and aromatic plants can absorb and accumulate metal contaminants in the harvestable foliage and, therefore, considered to be a feasible alternative for remediation of polluted sites without any contamination of essential oils. Plants use different strategies and complex arrays of enzymatic and non-enzymatic anti-oxidative defense systems to cope with overproduction of ROS causes from the heavy metals entered their cells through foliar and/or root systems. This review summarizes the reports of recent investigations involving heavy metal accumulation by medicinal plants and its effects on elicitation of secondary metabolites, toxicity and detoxification pathways, international standards regarding in plants and plant-based products, and human health risk assessment of heavy metals in soil-medicinal plants systems. Copyright © 2017 Elsevier Inc. All rights reserved.
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Content Heavy Metal Pb, Cd In Perna viridis And Sediments In Semarang Bay
NASA Astrophysics Data System (ADS)
Suprapto, D.; Suryanti, S.; Latifah, N.
2018-02-01
Waste disposal from human activities, generally contain heavy metals such as Pb and Cd which derived from industrial activities. The aims of the study were to know the concentration of Pb and Cd heavy metals contained in Perna viridis tissue, sediment and water at Semarang Bay. This study was conducted in May 2017 at Semarang Bay. - Samples were collected using purposive sampling method. The heavy metal content in the water and clam was observed using- APHA method and was analyzed using AAS (Atomic Absorption Spectrophotometer). The results showed that concentration of heavy metal of Pb in the water was 0.00-50.5mg/L and the Cd content was of 26.9-51.7 mg/L, whereas the concentration of Pb in the sediment is 445.5-2.053.0mg/L and Cd 963.3-2,150.0 mg/L. Pb content in soft tissue of Perna viridis - is 67.1-1.933.9 mg/L and the concentration of Cd was 203.5-5.787.3 mg/L. The analysis of Pb and Cd in seawater, sediment and soft tissue of Perna viridis according to Enviroment Ministerial decree (KepMenLH ) number 51 of 2004 and applied by NOAA 1999 does not exceed the quality standard, that meant that the Perna viridis has been contaminated by metal Pb it is controversial with the above sentence and Cd. It concluded that the metal content of Pb and Cd in Perna viridis tissue exceeds the quality standard, so it is not suitable to be consumed, especially in high quantity
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The inventory and distribution of water on Mars
Carr, M.H.
1987-01-01
Terrain softening, fretted channels, debris flows, and closed depressions indicate that at least the upper 2 km of the cratered uplands at high latitudes (>30??) contain ice in amounts that exceed the porosity, estimated to be 10-20 percent. Theoretical studies, and lack of these features in the cratered uplands at low latitudes, suggest that the upper 1 km of the uplands at low latitudes is ice poor. However, valley networks indicate that water was present near the surface early in the planet's history, although in amounts smaller than at high latitudes. On the basis of these observations, the entire upper 1 km, planet-wide is estimated to have contained 75-125 meters of water at the end of heavy bombardment. From the volume of water needed to cut the circum-Chryse channels, and assuming uniform planet-wide distribution of water, the deep megaregolith is estimated to have contained at least 350 meters of water at the end of heavy bombardment, thereby giving a total minimum inventory of 425-475 meters planet-wide. Most of the water lost from the low latitude uplands by diffusion and in cutting the valley networks is now believed to be in the polar layered terrains. Most of the water involved in cutting the outflow channels is in the low-lying northern plains where a variety of features that have been attributed to ground ice is present. Since the end of heavy bombardment, a large fraction of the planet's surface has been overplated with water-poor volcanics, of which we have samples in the SNC meteorites. The younger volcanics have reacted extensively with the old volatile-rich basement. Part of the 10-20 bars of CO2 and 0.1 to 0.3 bars of N2 outgassed with the water was lost during heavy bombardment by impact erosion of the atmosphere and other processes. The remaining was fixed carbonates and nitrates and folded deep into the megaregolith during heavy bombardment. ?? 1987.
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Hu, Jing; Zhou, Shaoqi; Wu, Pan; Qu, Kunjie
2017-01-01
In this study, selected heavy metals (Hg, As, Cd, Pb, Cr, Cu and Zn) in the lake water and sediments from the Caohai wetland, which is a valuable state reserve for migrant birds in China, were investigated to assess the spatial distribution, sources, bioavailability and ecological risks. The results suggested that most of the higher concentrations were found in the eastern region of the lakeshore. The concentration factor (CF) revealed that Hg, Cd and Zn were present from moderate risk levels to considerable risk levels in this study; thus, based on the high pollution load index (PLI) values, the Caohai wetland can be considered polluted. According to the associated effects-range classification, Cd may present substantial environmental hazards. An investigation of the chemical speciation suggested that Cd and Zn were unstable across most of the sites, which implied a higher risk of quick desorption and release. Principal component analysis (PCA) indicated that the heavy metal contamination originated from both natural and anthropogenic sources.
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Hu, Jing; Zhou, Shaoqi; Wu, Pan; Qu, Kunjie
2017-01-01
In this study, selected heavy metals (Hg, As, Cd, Pb, Cr, Cu and Zn) in the lake water and sediments from the Caohai wetland, which is a valuable state reserve for migrant birds in China, were investigated to assess the spatial distribution, sources, bioavailability and ecological risks. The results suggested that most of the higher concentrations were found in the eastern region of the lakeshore. The concentration factor (CF) revealed that Hg, Cd and Zn were present from moderate risk levels to considerable risk levels in this study; thus, based on the high pollution load index (PLI) values, the Caohai wetland can be considered polluted. According to the associated effects-range classification, Cd may present substantial environmental hazards. An investigation of the chemical speciation suggested that Cd and Zn were unstable across most of the sites, which implied a higher risk of quick desorption and release. Principal component analysis (PCA) indicated that the heavy metal contamination originated from both natural and anthropogenic sources. PMID:29253896
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Khrimian, Ashot; Lance, David R; Mastro, Victor C; Elkinton, Joseph S
2010-02-10
The winter moth, Operophtera brumata (Lepidoptera: Geometridae), is an early-season defoliator that attacks a wide variety of hardwoods and, in some cases, conifers. The insect is native to Europe but has become established in at least three areas of North America including southeastern New England. The female-produced sex attractant pheromone of the winter moth was identified as (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene (1), which also attracts a native congener, the Bruce spanworm, Operophtera bruceata . Dissection, or (for certainty) DNA molecular testing, is required to differentiate between males of the two species. Thus, a trapping method that is selective for winter moth would be desirable. A geometric isomer of the pheromone, (3E,6Z,9Z)-1,3,6,9-nonadecatetraene (2), can reportedly inhibit attraction of Bruce spanworm to traps without affecting winter moth catch, but use of the pheromone and inhibitor together has not been optimized, nor has the synthesis of the inhibitor. This paper presents two new syntheses of the inhibitor (3E,6Z,9Z)-1,3,6,9-nonadecatetraene based on the intermediate (3Z,6Z)-3,6-hexadecadien-1-ol (4), which has also been utilized in the synthesis of the pheromone. The syntheses combine traditional acetylenic chemistry and Wittig olefination reactions. In one approach, 2 was synthesized in 80% purity (20% being pheromone 1), and in the second, tetraene 2 of 96% purity (and free of 1) was produced in 25% overall yield from dienol 4. The last method benefitted from a refined TEMPO-mediated PhI(OAc)(2) oxidation of 4 and a two-carbon homologation of the corresponding aldehyde 7.
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Stormwater Effects on Heavy Metal Sequestration in a Bioretention System in Culver City, California
NASA Astrophysics Data System (ADS)
Yousavich, D. J.; Ellis, A. S.; Dorsey, J.; Johnston, K.
2017-12-01
Rain Gardens, also referred to as bioretention or biofilters, are often used to capture or filter urban runoff before it drains into surface or groundwater systems. The Culver City Rain Garden (CCRG) is one such system that is designed to capture and filter runoff from approximately 11 acres of mixed-use commercial and industrial land before it enters Ballona Creek. The EPA has designated Ballona Creek as an impaired waterway and established Total Maximum Daily Loads for heavy metals. Previous research has utilized sequential extractions to establish trends in heavy metal sequestration for Cu, Pb, and Zn in bioretention media. The aim of this project is to evaluate if there is a difference in heavy metal sequestration between dry and wetted bioretention media. To characterize the stormwater at the site, influent and surface water were collected and analyzed for sulfate and heavy metals 3 times during the 2016-2017 storm season. Two soil cores from the CCRG were acquired in the summer of 2017 to analyze soil metal sequestration trends. They will be subjected to different wetting conditions, sectioned into discrete depths, and digested with an established sequential extraction technique. Surface water in the CCRG shows average Dissolved Oxygen during wet conditions of 2.92 mg/L and average pH of 6.1 indicating reducing conditions near the surface and the possible protonation of adsorption sites during wet weather conditions. Influent metal data indicate average dissolved iron levels near 1 ppm and influent Cu, Pb, and Zn levels near 0.05, 0.01, and 0.5 ppm respectively. This coupled with average surface water sulfate levels near 3 ppm indicates the potential for iron oxide and sulfide mineral formation depending on redox conditions. The sequential extraction results will elucidate whether heavy metals are adsorbed or are being sequestered in mineral formation. These results will allow for the inclusion of heavy metal sequestration trends in the design of further
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Quantum dot impregnated-chitosan film for heavy metal ion sensing and removal.
Jaiswal, Amit; Ghsoh, Siddhartha Sankar; Chattopadhyay, Arun
2012-11-06
We report the use of biopolymer-stabilized ZnS quantum dots (Q-dots) for cation exchange reaction-based easy sensing and removal of heavy metal ions such as Hg(2+), Ag(+), and Pb(2+) in water. Chitosan-stabilized ZnS Q-dots were synthesized in aqueous medium and were observed to have been converted to HgS, Ag(2)S, and PbS Q-dots in the presence of corresponding ions. The transformed Q-dots showed characteristic color development, with Hg(2+) being exceptionally identifiable due to the visible bright yellow color formation, while brown coloration was observed in other metal ions. The cation exchange was driven by the difference in the solubility product of the reactant and the product Q-dots. The cation exchanged Q-dots preserved the morphology of the reactant Q-dots and displayed volume increase based on the bulk crystal lattice parameters. The band gap of the transformed Q-dots showed a major increase from the corresponding bulk band gap of the material, demonstrating the role of quantum confinement. Next, we fabricated ZnS Q-dot impregnated chitosan film which was used to remove heavy metal ions from contaminated water as measured using atomic absorption spectroscopy (AAS). The present system could suitably be used as a simple dipstick for elimination of heavy metal ion contamination in water.
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Geothermal and heavy-oil resources in Texas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seni, S.J.; Walter, T.G.
1994-01-01
In a five-county area of South Texas, geopressured-geothermal reservoirs in the Paleocene-Eocene Wilcox Group lie below medium- to heavy-oil reservoirs in the Eocene Jackson Group. This fortuitous association suggests the use of geothermal fluids for thermally enhanced oil recovery (TEOR). Geothermal fairways are formed where thick deltaic sandstones are compartmentalized by growth faults. Wilcox geothermal reservoirs in South Texas are present at depths of 11,000 to 15,000 ft (3,350 to 4,570 m) in laterally continuous sandstones 100 to 200 ft (30 to 60 m) thick. Permeability is generally low (typically 1 md), porosity ranges from 12 to 24 percent, andmore » temperature exceeds 250{degrees}F (121{degrees}C). Reservoirs containing medium (20{degrees} to 25{degrees} API gravity) to heavy (10{degrees} to 20{degrees} API gravity) oil are concentrated along the Texas Coastal Plain in the Jackson-Yegua Barrier/Strandplain (Mirando Trend), Cap Rock, and Piercement Salt Dome plays and in the East Texas Basin in Woodbine Fluvial/Deltaic Strandplain and Paluxy Fault Line plays. Injection of hot, moderately fresh to saline brines will improve oil recovery by lowering viscosity and decreasing residual oil saturation. Smectite clay matrix could swell and clog pore throats if injected waters have low salinity. The high temperature of injected fluids will collapse some of the interlayer clays, thus increasing porosity and permeability. Reservoir heterogeneity resulting from facies variation and diagenesis must be considered when siting production and injection wells within the heavy-oil reservoir. The ability of abandoned gas wells to produce sufficient volumes of hot water over the long term will also affect the economics of TEOR.« less