DOCSLIB.ORG

Determination of Some Trace Metals in Elsaraf Dam (Gedaref)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Determination of Some Trace Metals in Elsaraf Dam (Gedaref) DETERMINATION OF SOME TRACE METALS IN ELSARAF DAM (GEDAREF) By Tayser Ismail Yagoob A thesis submitted in fulfillment of the requirement for the degree of Master of Science (Chemistry) in the University of Khartoum Department of Chemistry Faculty of Science University of Khartoum, Sudan July 2001 LIST OF CONTENTS page List of Tables iv List of Figures vi Acknowledgment ix Abstract ( in Arabic) x Abstract (in English) xi CHAPTER ONE 1.Introduction 1 1.1 Trace elements. 1 1.1.1. Classification of trace elements. 1 1.1.1.1. Essential trace elements. 2 1.1.1.2. Non essential trace elements. 3 1.1.1.3. Toxic trace elements. 3 1.1.2 Trace elements in living organisms. 3 1.1.3. Trace elements in soils. 4 1.1.4.Trace elements in water. 5 1.1.5.Trace elements in plant. 6 1.1.6. Biological role of trace elements. 7 1.1.7. Individual nutrients. 9 1.1.7.1. Iron. 9 1.1.7.2. Manganese. 10 1.1.7.3. Copper. 12 1.1.7.4. Cobalt. 14 1.1.7.5. Nickel. 14 1.1.7.6. Zinc. 15 1.1.8 Individual pollutants 16 1.1.8.1 Cadmium. 16 1.1.8.2 Chromium. 18 1.2. Atomic spectroscopy. 20 1.2.1 Theory of atomic spectroscopy. 20 1.2.2. Flame atomization. 21 1.2.3. Instruments. 24 1.2.4. Theory of atomic absorption spectroscopy. 24 1.3. X-ray fluorescence methods. 25 1.3.1. Principles. 26 1.3.2. Instruments. 27 1.3.3. Wavelength dispersive instruments. 27 1.3.4. Energy dispersive instruments. 28 1.3.5. Nondispersive instruments. 29 1.3.6. Advantages and disadvantages of X-ray 30 fluorescence method. 1.4. Metal ions preconcentration. 31 1.4.1. Chelation and solvent extraction. 32 1.4.2. Dithiocarbamate extraction method. 33 1.4.3. 8-hydroxyquinoline (oxine). 35 Research objective 37 CHAPTRTWO 2. EXPERIMENTAL 2.1. Instruments. 38 2.2.Chemicals. 38 2.3. Samples collections. 38 2.4. AAS. Measurements. 39 2.4.1. Sample preparations. 39 2.4.1.1. Plantand soil samples. 39 2.4.1.2. Water samples. 40 2.4.1.2.1. Oxine extraction procedure. 40 2.4.1.2.2. APDC-MIBK extraction procedure. 40 2.4.2. Preparations of standards. 41 2.4.3. Calibration. 42 2.5. X-ray fluorescence. 42 2.5.1. Samples treatments and XRF measurements. 42 CHAPTRE THREE 3. DISCUSSION. 81 REFERENCES. 84 LIST OF TABLES page Table 1. Iron concentration (ppm) for soil and plant (first 43 season) Table 2. Copper concentration (ppm) for soil and plant 43 (first season) Table 3. Cobalt concentration (ppm) for soil and plant 44 (first season) Table 4 Manganese concentration (ppm) for soil and plant 44 (first season) Table 5. Chromium concentration (ppm) for soil and plant 45 (first season) Table 6. Nickel concentration (ppm) for soil and plant 45 (first season) Table 7. Cadmium concentration (ppm) for soil and plant 46 (first season) Table 8. Zinc concentration (ppm) for soil and plant (first 46 season) Table 9. Iron concentration (ppm) for soil and plant 47 (second season) Table 10. Copper concentration (ppm) for soil and plant 47 (second season) Table 11. Cobalt concentration (ppm) for soil and plant 48 (second season) Table 12. Manganese concentration (ppm) for soil and 48 plant (second season) Table 13. Chromium concentration (ppm) for soil and 49 plant (second season) Table 14. Nickel concentration (ppm) for soil and plant 49 (second season) Table 15. Cadmium concentration (ppm) for soil and plant 50 (second season) Table 16. Zinc concentration (ppm) for soil and plant 50 (second season) Table 17. Comparison of the AAS results obtained with 51 the certified values for the CRM of soil-7. Table 18. Comparison of the AAS results obtained with 51 the certified values for the CRM of hay powder. Table 19. Water metal ions concentration (ppm) using 52 oxine (first season): Table 20. Water metal ions concentration (ppm) using 53 oxine (2nd season): Table 21. Water metal ions concentration (ppm) using 54 APDC (2nd season): Table 22. Efficiency of oxine (pH 6.5) 55 Table 23. Efficiency of APDC (pH 4) 56 Table 24. Botanical and common names of the plants 77 investigated. Table 25. Location of the sites for water samples. 80 LIST OF FIGURES Page Fig. 1. XRF and AAS concentrations of iron for the first season 57 (soil). Fig. 2. XRF and AAS concentrations of copper for the first season 57 (soil). Fig. 3. XRF and AAS concentrations of cobalt for the first season 58 (soil). Fig. 4. XRF and AAS concentrations of manganese for the first 58 season (soil). Fig. 5. XRF and AAS concentrations of chromium for the first 59 season (soil). Fig. 6. XRF and AAS concentrations of nickel for the first season 59 (soil). Fig. 7. XRF and AAS concentrations of iron for the first season 60 (plant). Fig. 8. XRF and AAS concentrations of copper for the first season 60 (plant). Fig. 9. XRF and AAS concentrations of cobalt for the first season 61 (plant). Fig. 10. XRF and AAS concentrations of manganese for the first 61 season (plant). Fig. 11. XRF and AAS concentrations of chromium for the first 62 season (plant). Fig. 12. XRF and AAS concentrations of nickel for the first 62 season (plant). Fig. 13. Concentrations of iron for the first and second season in 63 the soil using AAS. Fig. 14. Concentrations of copper for the first and second season 63 in the soil using AAS. Fig. 15. Concentrations of cobalt for the first and second season 64 in the soil using AAS. Fig. 16. Concentrations of manganese for the first and second 64 season in the soil using AAS. Fig. 17. Concentrations of chromium for the first and second 65 season in the soil using AAS. Fig. 18. Concentrations of nickel for the first and second season 65 in the soil using AAS. Fig. 19. Concentrations of cadmium for the first and second 66 season in the soil using AAS. Fig. 20. Concentrations of zinc for the first and second season in 66 the soil using AAS. Fig. 21. Concentrations of iron for the first and second season in 67 the plant using AAS. Fig. 22. Concentrations of copper for the first and second season 67 in the plant using AAS. Fig. 23. Concentrations of cobalt for the first and second season 68 in the plant using AAS. Fig. 24. Concentrations of manganese for the first and second 68 season in the plant using AAS. Fig. 25. Concentrations of chromium for the first and second 69 season in the plant using AAS. Fig. 26. Concentrations of nickel for the first and second season 69 in the plant using AAS. Fig. 27. Concentrations of cadmium for the first and second 70 season in the plant using AAS. Fig. 28. Concentrations of zinc for the first and second season in 70 the plant using AAS. Fig. 29. Concentration of iron for the first and second season in 71 the water using oxine. Fig. 30. Concentration of copper for the first and second season in 71 the water using oxine. Fig. 31. Concentration of cobalt for the first and second season in 72 the water using oxine. Fig. 32. Concentration of manganese for the first and second 72 season in the water using oxine. Fig. 33. Concentration of chromium for the first and second 73 season in the water using oxine. Fig. 34. Concentration of nickel for the first and second season in 73 the water using oxine. Fig. 35. Extraction efficiency for iron using APDC and Oxine. 74 Fig. 36. Extraction efficiency for copper using APDC and Oxine. 74 Fig. 37. Extraction efficiency for cobalt using APDC and Oxine. 75 Fig. 38. Extraction efficiency for manganese using APDC and 75 Oxine. Fig. 39. Extraction efficiency for chromium using APDC and 76 Oxine. Fig. 40. Extraction efficiency for nickel using APDC and Oxine. 76 Fig. 41. Extraction efficiency for zinc using APDC and Oxine. 77 Fig. 42. Concentrations of some trace elements in water samples 78 using Oxine (first season). Fig. 43. Concentrations of some trace elements in water samples 79 using Oxine (second season). ACKNOWLEDGMENT Firstly, praise be to Allah. My appreciation and gratitude, to my honourable supervisor Dr. Taj Elsir Abbas Ahmed, for his continuous support. encouragement, valuable counsel, patience and guidance to finish this work. I am greatly indebted to Dr. Mohamed Ahmed Hassan Eltayeb (Sudan Atomic Energy Commission) [SAEC], for his invaluable assistance and directions throughout the work. My appreciation extends to the statTof Urban Water Authority (Gedareff State), for their help, financial support and facilities in sample collection. I woud like to express my thanks to the staff of Geological and Reseach Authority of The Sudan (Chemistry Laboratory), for allowing me to use the laboratory facilities . At last and not least, I wish to express my deepest gratitude to my friends and all statTof Chemistry Department, University of Khartoum for their assistance, the fruit and pleasure time I spend with them. .• -j' '-«" AJV JJ ^-ij J ^' :— ^—J T . *. • •!j^- - ^ • ^ -' ^ • '' r j - •*•' ^JLJ ^jj - -j - ^i '^ '-j-^ •*•- jjliiAll ^;-j » Ajt^VI . ..L J^ja. ^^.'.. I LailJ Ajjjll j ^lLlj]l J 6LJ CJUJC JjLkjl (AAS) . J^W^AII ^£ ^ OUjil j Ajjjil CJUJC ^_|n:v Jj^'^ (XRF) «ui ^J ij^i ^uyii JJSJ; j^, «xai ji^y Ujd =i» ^.^i I Ui ^i JSJI fi Jjivull •Ui (36800/33580 ,56600/54900) LJIj ^Gbill AJU U% ^UJJVI j^.L^L.7 AJLU ^ULO« JJSI jlS Sj^JI ^U; Amin niium pyrrolidinc dithiocarbamate j 8-hydroxyquinolinc.
Load more

Recommended publications
  • Cobalt Publications Rejected As Not Acceptable for Plants and Invertebrates
    Interim Final Eco-SSL Guidance: Cobalt Cobalt Publications Rejected as Not Acceptable for Plants and Invertebrates Published literature that reported soil toxicity to terrestrial invertebrates and plants was identified, retrieved and screened. Published literature was deemed Acceptable if it met all 11 study acceptance criteria (Fig. 3.3 in section 3 “DERIVATION OF PLANT AND SOIL INVERTEBRATE ECO-SSLs” and ATTACHMENT J in Standard Operating Procedure #1: Plant and Soil Invertebrate Literature Search and Acquisition ). Each study was further screened through nine specific study evaluation criteria (Table 3.2 Summary of Nine Study Evaluation Criteria for Plant and Soil Invertebrate Eco-SSLs, also in section 3 and ATTACHMENT A in Standard Operating Procedure #2: Plant and Soil Invertebrate Literature Evaluation and Data Extraction, Eco-SSL Derivation, Quality Assurance Review, and Technical Write-up.) Publications identified as Not Acceptable did not meet one or more of these criteria. All Not Acceptable publications have been assigned one or more keywords categorizing the reasons for rejection ( Table 1. Literature Rejection Categories in Standard Operating Procedure #4: Wildlife TRV Literature Review, Data Extraction and Coding). No Dose Abdel-Sabour, M. F., El Naggr, H. A., and Suliman, S. M. 1994. Use of Inorganic and Organic Compounds as Decontaminants for Cobalt T-60 and Cesium-134 by Clover Plant Grown on INSHAS Sandy Soil. Govt Reports Announcements & Index (GRA&I) 15, 17 p. No Control Adams, S. N. and Honeysett, J. L. 1964. Some Effects of Soil Waterlogging on the Cobalt and Copper Status of Pasture Plants Grown in Pots. Aust.J.Agric.Res. 15, 357-367 OM, pH Adams, S.
    [Show full text]
  • Undocumented Water Column Sink for Cadmium in Open Ocean Oxygen-Deficient Zones
    Undocumented water column sink for cadmium in open ocean oxygen-deficient zones David J. Janssena, Tim M. Conwayb, Seth G. Johnb, James R. Christianc, Dennis I. Kramera, Tom F. Pedersena, and Jay T. Cullena,1 aSchool of Earth and Ocean Sciences, University of Victoria, Victoria, BC, Canada V8W 2Y2; bDepartment of Earth and Ocean Sciences, University of South Carolina, Columbia, SC 29208; and cFisheries and Oceans Canada, Victoria, BC, Canada V8W 3V6 Edited by Edward A. Boyle, Massachusetts Institute of Technology, Cambridge, MA, and approved April 4, 2014 (received for review February 6, 2014) 3− Cadmium (Cd) is a micronutrient and a tracer of biological this sink induces local changes in Cd:PO4 must be understood productivity and circulation in the ocean. The correlation between to correctly interpret paleoceanographic records. dissolved Cd and the major algal nutrients in seawater has led to the use of Cd preserved in microfossils to constrain past ocean nutrient Results and Discussion distributions. However, linking Cd to marine biological processes Cadmium and other trace metals such as copper (Cu) and zinc requires constraints on marine sources and sinks of Cd. Here, we (Zn) are known to form solid sulfide precipitates in the ocean show a decoupling between Cd and major nutrients within oxygen- under conditions of anoxia where sulfide is present. For example, deficient zones (ODZs) in both the Northeast Pacific and North precipitation of Cd sulfide (CdS) (13) leading to dissolved Cd Atlantic Oceans, which we attribute to Cd sulfide (CdS) precipitation depletion is observed at oxic–anoxic interfaces in stratified basins in euxinic microenvironments around sinking biological particles.
    [Show full text]
  • Evaluation of the Trace Metal Supplements for a Synthetic Low Lactose Diet
    Arch Dis Child: first published as 10.1136/adc.58.6.433 on 1 June 1983. Downloaded from Archives of Disease in Childhood, 1983, 58, 433-437 Evaluation of the trace metal supplements for a synthetic low lactose diet P J AGGETT, J MORE, J M THORN, H T DELVES, M CORNFIELD, AND B E CLAYTON Department of Chemical Pathology, Institute of Child Health, London SUMMARY A trace element supplement used with a synthetic low lactose milk (Galactomins 17 and 18) has been evaluated by means of metabolic balance studies in 4 infants with dissacharide intolerances. The supplement was considered satisfactory for iron and manganese but increases in its zinc and copper content are probably necessary to ensure adequate retentions ofthese metals. Diets used in the management of infants with synthetic low lactose milks (Galactomins 17 and 18, inborn errors of metabolism or dietary intolerances Cow and Gate Ltd) has been assessed. There may have an inadequate essential trace element are three similar Galactomin products which are content."-3 This deficiency may be quantitative in derived from demineralised casein and which are as much as these micronutrients are lost during prepared according to a formula elaborated in this manufacture of the diet, or it may be a qualitative department.5 They are used in the management of defect resulting from postulated interactions between dietary lactose intolerances (Galactomins 17, 18, and these elements and other inorganic and organic 19) and of inborn errors of galactose metabolism dietary constituents which reduce intestinal
    [Show full text]
  • Trace Metal Toxicity from Manure in Idaho: Emphasis on Copper
    Proceedings of the 2005 Idaho Alfalfa and Forage Conference TRACE METAL TOXICITY FROM MANURE IN IDAHO: EMPHASIS ON COPPER Bryan G. Hopkins and Jason W. Ellsworth1 TRACE METALS: TOXIC OR ESSENTIAL Plants have need for about 18 essential nutrients. Of these essential nutrients, several are classified as trace metals, namely: zinc, iron, manganese, copper, boron, molybdenum, cobalt, and nickel. In addition, other trace metals commonly exist in soil that can be taken up, such as arsenic, chromium, iodine, selenium, and others. Some of these elements are more or less inert in the plant and others can be utilized although they are not essential. Animals also have requirements for trace elements. Although plants require certain trace elements, excessive quantities generally cause health problems. Plants typically show a variety of symptoms that depend on element and species, but there is generally a lack of vigor and root growth, shortened internodes, and chlorosis. Boron and copper are the two micronutrients most likely to induce toxicity. However, one time high rates of copper have been shown to be tolerated in some cases, but accumulations have been shown to be toxic in others. Copper has been used for centuries as a pesticide and, although bacteria and fungi are relatively more susceptible to it, excessively high exposure is detrimental to plants. Manganese toxicity is also common, but generally only in very acidic soils. Lime application raises pH and reduces the manganese solubility. Zinc and iron have a similar pH relationship, but are less frequently toxic in acid soils. Zinc, iron, manganese, and copper have a known relationship with phosphorus as well.
    [Show full text]
  • How Do Bacterial Cells Ensure That Metalloproteins Get the Correct Metal?
    REVIEWS How do bacterial cells ensure that metalloproteins get the correct metal? Kevin J. Waldron and Nigel J. Robinson Abstract | Protein metal-coordination sites are richly varied and exquisitely attuned to their inorganic partners, yet many metalloproteins still select the wrong metals when presented with mixtures of elements. Cells have evolved elaborate mechanisms to scavenge for sufficient metal atoms to meet their needs and to adjust their needs to match supply. Metal sensors, transporters and stores have often been discovered as metal-resistance determinants, but it is emerging that they perform a broader role in microbial physiology: they allow cells to overcome inadequate protein metal affinities to populate large numbers of metalloproteins with the right metals. It has been estimated that one-quarter to one-third of all Both monovalent (cuprous) copper, which is expected proteins require metals, although the exploitation of ele- to predominate in a reducing cytosol, and trivalent ments varies from cell to cell and has probably altered over (ferric) iron, which is expected to predominate in an the aeons to match geochemistry1–3 (BOX 1). The propor- oxidizing periplasm, are also highly competitive, as are tions have been inferred from the numbers of homologues several non-essential metals, such as cadmium, mercury of known metalloproteins, and other deduced metal- and silver6 (BOX 2). How can a cell simultaneously contain binding motifs, encoded within sequenced genomes. A some proteins that require copper or zinc and others that large experimental estimate was generated using native require uncompetitive metals, such as magnesium or polyacrylamide-gel electrophoresis of extracts from iron- manganese? In a most simplistic model in which pro- rich Ferroplasma acidiphilum followed by the detection of teins pick elements from a cytosol in which all divalent metal in protein spots using inductively coupled plasma metals are present and abundant, all proteins would bind mass spectrometry4.
    [Show full text]
  • Global Biogeochemical Cycle of Vanadium
    Global biogeochemical cycle of vanadium William H. Schlesingera,1, Emily M. Kleina, and Avner Vengosha aEarth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, NC 27708 Contributed by William H. Schlesinger, November 9, 2017 (sent for review September 1, 2017; reviewed by Robert A. Duce, Andrew J. Friedland, and James N. Galloway) Synthesizing published data, we provide a quantitative summary problematic environmental contaminant, but high concentrations of the global biogeochemical cycle of vanadium (V), including both of V can be toxic to humans and other organisms (18, 19). human-derived and natural fluxes. Through mining of V ores Reflecting a new level of concern, the State of California has re- (130 × 109 g V/y) and extraction and combustion of fossil fuels cently imposed a new standard (15 μg/L) for V in drinking water (600 × 109 g V/y), humans are the predominant force in the geo- (https://oehha.ca.gov/water/notification-level/proposed-notifica- chemical cycle of V at Earth’s surface. Human emissions of V to the tion-level-vanadium). In some regions, the release of V to the atmosphere are now likely to exceed background emissions by as atmosphere and its deposition in natural ecosystems have de- much as a factor of 1.7, and, presumably, we have altered the clined in recent decades due to changes in fuel use and industrial deposition of V from the atmosphere by a similar amount. Exces- practices (20, 21). sive V in air and water has potential, but poorly documented, Vanadium’s primary commercial use is in the manufacture consequences for human health.
    [Show full text]
  • Trace Metal Nutrition of Avocado
    TRACE METAL NUTRITION A. OF AVOCADO David E. Crowley1, Woody Smith1, Ben Faber2, A. Zinc deficiency 3 Mary Lu Arpaia Typical leaf zinc deficiency 1 Dept. of Environmental Science, University of California, Riverside, CA symptoms. Note the chlorosis 2UC Cooperative Extension, Ventura County, CA (yellowing) between veins and 3UC Kearney Agricultural Center, Parlier, CA the reduced leaf size (top). B. Iron deficiency SUMMARY Iron deficiency symptoms on It is easy to confuse zinc and iron deficiency symptoms, new growth. Iron deficiency so growers should rely on annual leaf analysis. Also, it is and zinc deficiency are easily essential for avocado growers to know their soil pH, confused. and soil iron and zinc levels before embarking on a fertilization program. For zinc, best results are with soil B. application through fertigation or banding, and there is no apparent advantage to using chelated zinc. For iron fertilization, the best solution is to use soil applied Sequestrene 138, an iron chelate. It is highly stable and can last for several years recycling many times to deliver more iron to the roots. It is important not to mix trace metal fertilizers with phosphorus fertilizers. INTRODUCTION Avocados require many different nutrients for growth that include both macro and micronutrients. Macronutrients such as nitrogen, potassium and phosphorus are generally provided as fertilizers. Micronutrients are those nutrients that are essential for plant growth and reproduction, but are only required development of small round fruit. The first step in treating at very low concentrations. Most micronutrients, or trace trace metal deficiencies is to determine exactly which elements, are involved as constituents of enzyme metal micronutrients are limiting since both iron and zinc molecules and other organic structures.
    [Show full text]
  • Trace Metal Detection Technique in Law Enforcement
    If you have issues viewing or accessing this file contact us at NCJRS.gov. Trace Metal This microfiche was produced from dotuments received for Detection Technique inclusion in the NCJRS data base. Since NCJRS cannot eurcise in Law Enforcement control over the physical cDndition of the documents submitted, the individual flame quality will vary. The resolution chart on PR 71-1 this frame may be used to evaluate the document quality. \: OCTOBER 1970 ,, . 2 5 ~~ 111112.8 11111 . 1.0 3 2 11111 . Db>~ ' I .z; IIIF6 I" I~ 1,1.10 20 .: I!ill~ • • t.. ~ 1.1 &..iL..!.i. A manual describing the technique for de­ _ 111111.8 tecting and identifying traces and specific patterns left on suspects' skin and clothing by weapons. tools and other metal objects. 111111.25 111111.4 111111.6 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS-1963·A .. \ Microfilming procedures used to create this fiche comply with the standards set forth in 41CFR 101·11.504 Points of view or opinions' stated in this document are U.S. DEPARTMENT OF JtJSTICE . law Enforcement Assistance Administration those of ihe author[s) and do not represent the official National Institute of law Enforcement and Criminal Justice position or policies of the U.S. Department of Justice. For sale by the Superintendent of Documents, U.S. Government Printing Office U.~. DEPARTMENT OF JUSTICE Washington, D.O. 20402· Price 20 cents LAW ENFORCEMENT ASSISTANCE ADMINISTRATION NATIONAL CRIMiNAL JUSTICE REFERENCE SERVICE WASHINGTON, D.C. 20531 . __ ,_' ",~.>.'~' "~ ~ ~1<'." .' -- 1.&a!2 TABLE OF CONTENTS Page I. INTRODUCTION 1 II.
    [Show full text]
  • The Geochemistry of Vanadium Within the Subterranean Estuary of Stony Brook Harbor, NY Michael T
    The Geochemistry of Vanadium within the Subterranean Estuary of Stony Brook Harbor, NY Michael T. Thorpe and Caitlin Young Department of Geosciences, Stony Brook University Stony Brook, NY 11794 [email protected] The subterranean estuary (STE) is defined as the zone of mixing between fresh groundwater and seawater within coastal aquifers [Moore, 1999]. The boundary produced by this transition creates unique geochemical conditions that in turn controls the trace metal flux from terrestrial derived groundwater to the coastal surface water. This study investigates the cycling and speciation of trace metals, in particular Vanadium, within the STE of Stony Brook Harbor, where oxic groundwater interacts with suboxic seawater. We address how this geochemical transformation in the STE may alter the final trace metal composition of the groundwater being discharged. Results from porewater samples indicate that total dissolved V displays a co-varying behavior (Fig. 1) Figure 1. Total dissolved Fe vs. within the salinity transition zone with that of Fe. This trend is unique to this study site and indicates a mobilization of Fe and V due to the iron redox chemistry that is accompanied by re-sorption to the aquifer sediments upon reaching the upper salinity plume. However, this co- variation differs at the sediment water interface where V has an elevated concentration (Fig. 2). A spike in concentration at this interface makes V particularly interesting because this may indicate SGD as a potential source of Figure 2. Dissolved V transect in the STE. The arbitrary plume dissolved V to the surrounding surface emphasizes the salinity transitions. water, which coincides with previous work done in the Great South Bay of Long Island, NY [Beck et al., 2010].
    [Show full text]
  • The Role of Metals in Enzyme Activity*
    ANNALS OF CLINICAL AND LABORATORY SCIENCE, Vol. 7, No. 2 Copyright © 1977, Institute for Clinical Science The Role of Metals in Enzyme Activity* JAMES F. RIORDAN, Ph.D. Biophysics Research Laboratory, Department of Biological Chemistry, Harvard Medical School, and Division of Medical Biology, Veter Bent Brigham Hospital, Boston, MA 02115 ABSTRACT Metal ions play important roles in the biological function of many en­ zymes. The various modes of metal-protein interaction include metal-, ligand-, and enzyme-bridge complexes. Metals can serve as electron donors or acceptors, Lewis acids or structural regulators. Those that participate directly in the catalytic mechanism usually exhibit anomalous physicochemical characteristics reflecting their entatic state. Carboxypep- tidase A, liver alcohol dehydrogenase, aspartate transcarbamoylase and al­ kaline phosphatase exemplify the different roles of metals in metalloen- zymes while the nucleotide polymerases point to the essential role of zinc in maintaining normal growth and development. Introduction At present, reliable measurements of small concentrations of metals present in Certain metals have long been recog­ tissues, cells, subcellular particles, body nized to have important biological func­ fluids and biomacromolecules can be tions primarily as a consequence of nu­ performed by colorimetry, fluorimetry, tritional investigations.14,15,22 Thus, the polarography, emission spectrometry absence of a specific, essential metal with spark, flame or plasma excitation from the diet of an organism
    [Show full text]
  • C:\Eco-Ssls\Contaminant Specific Documents\Cobalt\November 2003\Final Eco-SSL for Cobalt.Wpd
    Ecological Soil Screening Levels for Cobalt Interim Final OSWER Directive 9285.7-67 U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 March 2005 This page intentionally left blank TABLE OF CONTENTS 1.0 INTRODUCTION .......................................................1 2.0 SUMMARY OF ECO-SSLs FOR COBALT ..................................2 3.0 ECO-SSL FOR TERRESTRIAL PLANTS....................................3 4.0 ECO-SSL FOR SOIL INVERTEBRATES....................................3 5.0 ECO-SSL FOR AVIAN WILDLIFE.........................................5 5.1 Avian TRV ........................................................5 5.2 Estimation of Dose and Calculation of the Eco-SSL ........................5 6.0 ECO-SSL FOR MAMMALIAN WILDLIFE ..................................8 6.1 Mammalian TRV ...................................................8 6.2 Estimation of Dose and Calculation of the Eco-SSL .......................11 7.0 REFERENCES .........................................................12 7.1 General Cobalt References ..........................................12 7.2 References Used for Derivation of Plant and Soil Invertebrate Eco-SSLs ......12 7.3 References Rejected for Use in Derivation of Plant and Soil Invertebrate Eco-SSLs ...............................................................13 7.4 References Used for Derivation of Wildlife TRVs ........................23 7.5 References Rejected for Use in Derivation of Wildlife TRVs ...............25
    [Show full text]
  • Trace Metal Geochemistry of Walker, Mono, and Great Salt Lakes
    fluid-Mineral Interactions: A Tribute to H. P. Eugster © The Geochemical Society, Special Publication No.2, 1990 Editors: R. J. Spencer and f-Ming Chou Trace metal geochemistry of Walker, Mono, and Great Salt Lakes JOSEPHL, DOMAGALSKI,*andHANSP. EUGSTERt Department of Earth and Planetary Sciences, The Johns Hopkins University, Baltimore, MD 21218, U.S.A. and BLAIRF. JONES United States Geological Survey, M.S. 432, Reston, VA 22092, U.S.A. Abstract-Recent sediments were collected from three Basin and Range closed basin lakes (Walker Lake, NV, Mono Lake, CA, and Great Salt Lake, UT) to evaluate the response of a suite of trace metals (Fe, Mn, Cu, Pb, Zn, Cd, Co, Mo, V) to diagenetic processes and assess reactivity, mobility, mineral transformations and precipitation, and organic complexation. Sediments and pore fluids, representing up to 1000 years of deposition, were analyzed for brine and metal composition, pH, alkalinity, and H2S. Sequential extractions of metals from solidswere valuable in locating core horizons where metals are mobilized or precipitated and in the interpretation of pore-fluid metal profiles. Sedimentary metals initially associated with Fe-Mn oxides and organic matter respond to changes in biologically induced redox conditions by forming sulfide solids and humic acid complexes. Walker Lake metals are tightly bound near the sediment-water interface by oxides which only slowly dissolve in the anoxic sediments. At 50-60 cm of sediment depth, dissolution of oxides results in the most extensive metal redistribution. At Great Salt Lake sedimenting particles are entrained within the dense bottom brines where maximum organic decomposition and H2S production occurs.
    [Show full text]