Дисертації: "Trace element chemistry"

1

Beere, Hugh Graham. "Study of trace element determination by ion chromatography with chemiluminescence detection." Thesis, University of Plymouth, 1995. http://hdl.handle.net/10026.1/1874.

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This thesis details the development of several highly sensitive liquid chromatography post-column reaction detectors based on chemiluminescence (CL) for the ion chromatography (IC) determination of metal species in a range of sample types. The first chapter describes a non-selective multi-element CL detector based on metal-ligand reactions involving cobalt (11) and EDTA. A complexation reaction was designed so that eluting metal species displaced or produced equivalent amount of free cobalt ions which then catalysed the CL oxidation of luminol. The effect of pH, temperature and reaction time was investigated and optimised. It was found that the detector responded to a wide range of metals capable of forming EDTA complexes, even the relatively weak complexes such as those of magnesium and calcium. However, problems with the high back-ground signal limited sensitivity to the low ug 1-1 range. The next chapter deals with the development of a highly sensitive IC method for the determination of two environmentally important chromium species, namely chromium (III) and chromium (VI). A rapid ion exchange separation was achieved using a single column with potassium chloride eluent. This was incorporated into a luminol-H2O2 CL detector, specific for chromium (III). On-line reduction was required in order to visualise the chromium (VI). Detection limits for chromium (III) and chromium (VI) wer 0.05 ug 1-1 and 0.1 /ug 1-1 respectively. Good results were obtained with a freshwater standard reference material and lyophilised samples as part of the author’s participation in a Bureau Communtaire de reference (BCR) certification exercise. Sample pH was found to have considerable influence on the stability of the species and this is described and discussed. The third and largest part of the study involved the development of an IC system for the ultra-trace determination of silver in pressurised water reactor (PWR) primary coolant, of particular concern to the nuclear power industry. A novel ion exchange separation was achieved on hydrophillic resins giving excellent separation from divalent cations. A CL post column reaction detector was designed based on the oxidation of luminol with persulphate. Good quantitative performance was accomplished based on the analysis of a certified reference material and simulated PWR coolant with detection limit for silver of 0.05 /ug 1-1. Finally, a CL detection system was developed for determining gold (III) after IC separation. A novel aspect was that no added co-oxidant was required for the luminol reaction. Results for a standard reference metal alloy sample was in good agreement with the certified value. Again, high sensitivity was achieved with a detection limit of 0.25 ug 1-1.

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2

Eisenhauer, Gary Bernard. "Trace-element chemistry of Quarternary ostracods as a palaeosalinity indicator in marginal marine environments." Thesis, Kingston University, 1999. http://eprints.kingston.ac.uk/20628/.

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The aim of this project is to evaluate the use of shell chemistry as a salinity indicator in marginal marine environments through the analysis of the elements Mg and Sr, although the significance of Mn and Fe concentrations are also assessed, within the ostracod valve and calculation of subsequent trace-element/Ca ratios. Two contrasting approaches were investigated; a modern environment where the salinity gradient is well established, and supported by previous work and field measurements (The Fleet, Dorset) and a Holocene sediment sequence where salinity was inferred from faunal palaeoecology of foraminifera and ostracods (Core SB1, Son Bou, Menorca). The species Cytherois fischeri, Leptocythere castanea, Leptocythere lacertosa, Loxoconcha rhomboidea and Xestoleberis nitida were analysed from the Fleet and generally show no relation to the host water chemistry and high variability at each study site, reflecting the tidal nature of the waterbody. However, L. lacertosa does show a weak negative trend in Mg/Ca across the transect, similar to the inverse relationships reported in a few previous studies (Teeter & Quick, 1990; Keyser et al., 1993 and Boomer, pers. comm.). Positive correlations between Sr/Ca ratios and nominal shell weight for all five species, suggests that part of the Sr content within the valve is simply related to the weight of the shell (i.e. the heavier the valve the more Sr within) and was not subsequently taken up in equilibrium with the host water. The species Cyprideis torosa and Loxoconcha elliptica were analysed from core SB1. The C. torosa Sr/Ca ratio correlated very strongly with the faunal and floral records, reflecting the environmental changes and salinity variations suggested along with the presence/absence of marine connections. The L. elliptica Sr/Ca record and Mg/Ca records for both species do not display such distinct correlations, although more subtle shifts involving increased variability do correlate with more unstable episodes and overall trends in the mean also correlate to hypothesised long term salinity trends. Positive correlation between L. elliptica Sr/Ca and nominal shell weight indicates that part of the Sr within the valve is simply related to the weight of the shell, thereby making the environmental evidence available from the L. elliptica chemistry record more limited than that of the C. torosa record. Therefore, despite the fact that the Fleet has a reduced tidal flow compared to a normal estuary, it would appear that the water chemistry is still too variable for the ostracod shell chemistry technique to be used as a reliable indicator of water chemistry, although the technique can be of limited use where corroborative evidence from other sources is necessary to support any conclusions.

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3

Muskara, Uftade. "Provenance Studies On Limestone Archaeological Artifacts Using Trace Element Analysis." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608429/index.pdf.

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Trace element composition of archaeological artifacts is commonly used for provenance studies. Limestone has generally studied by geologists and there are a few researches done by various archaeological sciences. Although it is a common material for buildings and sculpture it is been thought that limestone used had not imported like marbles. Limestone figurines from Datç
a/Emecik excavations are classified as Cypriote type, which was very popular through 6th century B.C. in the Mediterranean region. Since this type of figurines was found at Emecik numerously to determine its provenance was an important problem. Emecik figurines were examined for their some major, trace elements and REE compositions and results were compared with geological samples which were taken from a near by quarry. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), Inductively Coupled Plasma-Mass Spectrometry (ICPMS) have been used for analysis. The methods have been optimized by using standard reference material NIST 1d, NCS DC 73306, and IGS40.

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4

Dalbeck, Paul C. "Crystallography, stable isotope and trace element analysis of Mytilus edulis shells in the context of ontogeny." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/1870/.

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Living systems exert exquisite control over biomineral production determining mineral type, polymorph, morphology and ultrastructure and ultimately producing biomineral structures that perform a range of functions. In addition to this biological control, the environment also influences aspects of biomineralisation. In marine invertebrates, biominerals record seawater chemistry and temperature at deposition. Past chemistry and temperature information is interpreted via proxies such as oxygen isotope and Mg/Ca ratios in calcium carbonate biominerals and used to help predict future climatic trends. Proxies must be robust and accurate yet the presence of biological or biologically-induced kinetic effects, many of which are a consequence of ontogeny, can make it difficult to isolate the environmental signal. In many cases, proxies are applied without detailed knowledge or assessment of shell microstructures and how this is altered as the animal ages. Interpretation of detailed crystallographic, chemical and isotopic changes in the context of ontogeny is therefore essential. This study considers crystallography, trace element chemistry and stable isotopic composition of six ontogenetic stages of farmed Mytilus edulis collected from a single location at the same time. The shell of Mytilus edulis is comprised of two calcium carbonate polymorphs: an outer layer of prismatic calcite and an inner layer of nacreous aragonite, both with very different morphologies. The crystallographic ultrastructure is analysed through Electron Backscatter Diffraction (EBSD) and Scanning Electron Microscopy (SEM). No significant changes in crystallography are evident between ontogenetic stages. Crystallographic orientation of calcite is more strictly constrained towards the polymorph interface and from anterior to posterior in all stages of ontogeny. Further evidence of ‘mineral bridging’ is observed in nacre. The minor element distribution varies between the polymorphs, through the shell thickness and between ontogenetic stages. Younger specimens have higher Mg, S and Sr concentrations while older specimens have increasing Na concentrations. Mg and S are present in the calcite layer but are virtually absent in aragonite. While Na and Sr occur in both polymorphs, higher concentrations occur in aragonite. Changes in Na and Sr concentrations in the aragonite layer can be linked to prismatic bands of myostracal aragonite in the nacre. A decrease in Na concentration through the calcite layer toward the polymorph interface is observed in all specimens. Increases in Mg and S concentration in the calcite layer near the interface are often observed. Greater trace element concentrations are also observed in the umbo region of the shell. Stable oxygen isotope signatures show small amounts of variation between regions of the shell and between ontogenetic stages. Decreasing δ18O values are observed in older animals and in the posterior edge of the shell. Large variations of δ18O are also observed through the shell thickness which cannot be accounted for by environmental changes. The majority of δ18O data falls within the expected range for equilibrium of calcite and aragonite with ambient seawater. No significant change is observed in δ13C values between ontogenetic stages or through the shell. Values of δ13C and δ18O co-vary in aragonite but not calcite. Refinement in crystallography occurs in conjunction with changes in trace element chemistry and stable oxygen isotope composition moving towards the shell posterior. This indicates a change as the animal grows, resulting in differences in chemical information retained in different parts of the shell. The differences in trace element chemistry between polymorphs and isotopic and chemistry changes across the shell thickness indicate changes that can be attributed to ultrastructure as crystal habit, polymorph and orientation change occur across the shell thickness. These results suggest that greater understanding of factors involved in biomineralising systems is required before undertaking work involving application of climate proxies.

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5

Smith, Kurt Thomas. "Evaluation of fin ray and fin spine chemistry as indicators of environmental history for five fish species." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/261.

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Knowledge of environmental history is important for the management and conservation of fish populations. Multiple methods to tag or mark fish have been developed (e.g., radio transmitters, coded wire tags, PIT tags, genetic markers), however, each of these methods has limitations. Naturally occurring and artificial chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in both marine and freshwater environments and are not subject to the shortcomings of conventional tagging methods. However, few studies have evaluated the application of fish fin rays as a non-lethal alternative to fish otoliths as a recorder of individual fish environmental history. Therefore, I evaluated the application of artificial and naturally occurring chemical markers in fish fin rays as tracers of individual environmental histories. Specifically, I sought to determine 1) if age-0 lake sturgeon pectoral fin rays could be marked by immersion in strontium carbonate (SrCO3) enriched with the stable isotope 86Sr (86SrCO3), 2) whether natural differences in otolith and fin spine chemistry are present in catfish species collected from the Mississippi River basin, and 3) whether natural differences in fin ray chemistry are present in smallmouth bass from different rivers and streams in northern Illinois. Results from the first objective indicated that age-0 lake sturgeon were marked with 83% success when reared in water enriched with 100 µg/L of 86SrCO3, compared to control fish, and mark retention was maintained for at least 120 d following the labeling period. Results of the second objective indicated that both catfish otolith Sr:Ca, δ18O, and δ13C and fin spine Sr:Ca differed among sites, reflecting geographic differences in water chemistry at source locations. Both structures classified fish to their environment of capture with a high degree of accuracy, except in the Middle and Lower Mississippi Rivers where many recent immigrants appeared to be present. Similarly, smallmouth bass fin ray core Sr:Ca differed among sites, reflecting previously documented differences in water chemistry among streams and rivers in northern Illinois. Classification accuracy of smallmouth bass to their environment of capture based on fin ray Sr:Ca was variable, as some rivers had similar water chemistry signatures. The use of artificial chemical marks in fin rays will be useful when marking small fish that may not respond well to physical tags, when non-lethal recovery is desirable, and to distinguish between multiple batches of stocked fish (i.e. to evaluate factors such as stocking location and timing, fish size, and when fish may become interspersed into the existing population). Natural chemical signatures in pectoral fin rays or fin spines may provide a non-lethal alternative to otoliths for gathering information on environmental history (e.g. stock mixing, recruitment sources) of smallmouth bass and catfishes, consistent with recent demonstrations of this technique's effectiveness in other fish species. Ultimately, the use of artificial and naturally occurring chemical marks in fish fin rays provides a non-lethal alternative method to evaluate the environmental history of all life stages of fish

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6

Johansson, Linn. "Trace Element Levels in Scalp Hair from Adolescents in Río Negro, Argentina : Link to Environmental and Dietary Factors." Thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-16048.

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This study provides an insight into a provincial region of a developing country, namely Río Negro, Argentina and possible links between diet, environmental factors (especially water quality) and human health. Measuring levels of trace elements in scalp hair is a known method for assessing nutritional status. Levels of Ca, Fe, Mg, K, Na, As, Cr, Co, Cu, I, Mn, Mo, Ni, Se, V, Zn, Al, Cd, Pb, Rb and Hg in scalp hair from adolescents of the age 14 to 18 years in a rural and an urban population of Río Negro were analysed by inductively coupled plasma mass spectroscopy (ICP-MS). The hypothesis is that levels of trace elements reflect lifestyle factors such as smoking, beverage and food selection and consumption patterns and are directly linked to dehydration and could be associated with future health problems. Furthermore, environmental factors, such as (i) indecent water systems and governmental subsidised food in the rural/urban population, and (ii) ingestion or inhalation of arsenic (from naturally high sources of water, dust and foodstuffs) may also be linked to present and future health problems. The relationship between environmental and dietary factors could be implicated with the onset of diseases such as diabetes type II, obesity or hypothyroidism. The results show that both study populations in the region are exposed to several trace elements in exceedingly high amounts such as As and Mn through tap water which may induce cancers. Also, regular soft drink consumption is associated with low Cr level in this population. Evidence was not obtained for assessing potential dehydration. In terms of understanding the relationship between these factors, methods for assessing dehydration and dietary consumption need to be perfected, and other demographic issues and methods for quantifying obesity and health status will require further research.

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7

Emproto, Christopher Robert. "Column Anion and Trace Element Chemistry of Apatite from Crustal Carbontite Deposits in the Grenville Province: Implications for Crustal Carbontite Genesi." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1596134287925232.

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8

Brisbin, Judith Ann. "EXTRACTION TECHNIQUES FOR TRACE ELEMENT DETERMINATIONS OF BIOLOGICAL AND ENVIRONMENTAL SAMPLES INCLUDING ELEMENTAL SPECIATION OF LOBSTER USING INDUCTIVELY COUPLED PLASMA - MASS SPECTROMETRY." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin998412111.

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9

Bergbower, Joshua N. "Trace and Rare Earth Element Chemistry of Fluorite from the Illinois-Kentucky Fluorspar District and its Implications for the Origins of Mineralizing Fluids." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1530269153862162.

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10

Palacios-Fest, Manuel Roberto. "Trace element shell chemistry of continental ostracodes and the applicability of experimentally-derived multiple regression models to paleoenvironmental reconstructions in southwestern North America." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186915.

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Lacustrine ostracodes have been studied during the last three decades because of their apparent utility in reconstructing aquatic paleoenvironments. These microcrustaceans are ideal for paleoenvironmental analysis because: (1) they are cosmopolitan and abundant lacustrine inhabitants; (2) they show high diversity; (3) they are sensitive to climate-related limnological variations; (4) their valves incorporate some trace elements from host waters that may provide information on paleolimnologic conditions; and (5) their valve calcification appears to be in oxygen stable isotopic equilibrium with the host water. I designed a two-part research project to understand the significance of ostracode shell chemistry in response to the environment. First, an experiment to determine the Mg²⁺and Sr²⁺ partition coefficients (K(p)) for Limnocythere staplini, a widely distributed species in North America was executed to establish its applicability to the geologic record. Three hundred specimens of this species were individually cultured in 20 ml capped vials at discrete temperatures (15, 20 and 25 °C) and conductivities (10, 15, 20, 25, 30 μMohs/cm). After the ostracodes molted, the carapaces were removed for Ca²⁺, Mg²⁺, and Sr²⁺ analysis by inductively coupled plasma mass spectrometry (ICP-MS). Ostracode shell chemistry shows that ᵐ(Mg/Ca)(valve} is temperature dependent but not related to ᵐ(Mg²⁺/Ca²⁺)(water}. ᵐ(Sr/Ca)(valve} is dependent on TDS and possibly to ᵐ(Sr²⁺/Ca²⁺)(water}. Experimental results are applicable to a limited number of water bodies within the ranges of these analyses. Second, the equations generated in these experiments were used in a case study from the geologic record to test the applicability of this technique. Las Acequias Hohokam irrigation system provided the material for the first attempt to use ostracode shell chemistry to reconstruct the history of canal operation during Hohokam occupation (8th-15th Century A.D.). One hundred and twenty nine valves of Limnocythere staplini were analyzed by ICP-MS. I studied these valve data and associated information to determine the human water usage patterns and impact on the environment by ancient Native Americans. Current results suggest that experimental ᵐ(Mg/Ca)(valve} ratios may be used as a paleothermometer to reconstruct aquatic paleoenvironments. ᵐ(Sr/Ca)(valve} may prove to be a reliable source for reconstructing paleosalinity. The combined trace element analyses provides a powerful tool for understanding both paleoclimatic and human impact changes. However, paleoenvironmental reconstructions through partition coefficients is not warranted because thermodynamic equilibrium may not exist between water and Limnocythere staplini.

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11

Trapp, John Michael. "Chemistry of Iron and Other Trace Elements in Trade Wind Aerosols and Precipitation." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/323.

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The atmospheric transport of various substances from the continents to the oceans plays an important role in biogeochemical processes. Trace metals, iron in particular is of great interest as its availability regulates the growth of phytoplankton over large areas of the ocean. This dissertation focuses on examining and characterizing the factors that affect the solubility of trace metals in Miami and Barbados aerosols and precipitation, in particular species that could play a role in surface seawater biogeochemistry (Fe and trace metals such as Al, V, Cr, Mn, Cu, Co, Ni, Zn, As, Tl, Ba, Cd, Pb, Th, Ti, Zr, and REE's). To enable this study existing methods of colorimetric spectroscopic and inductively coupled plasma mass spectrometry analysis were improved and modified. This dissertation examines several issues related to source inputs: 1.) Are single spot sources within the North African dust source distinguishable after long transport by their bulk metal composition and thus important in the characteristics of individual mineral dust samples? 2.) What is the temporal variability and controlling factors in trace metal solubility in trade wind aerosols collected over Barbados? 3.) Which factors control the observed trend of speciation and increasing iron solubility in decreasing aerosol loading? Additionally a kinetic model of species specific iron (II) to iron(III) oxidation kinetics in NaCl Brines was conducted at nano-molar levels. This study greatly expands the ability to predict rates of iron oxidation at concentrations closer to those observed in natural systems.

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12

Bull, Julia Ruth. "Stable isotope, major and trace element chemistry of modern snow from Evans Piedmont Glacier, Antarctica : insights into potential source regions and relationship of glaciochemistry to atmospheric circulation and vigour : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Geology /." ResearchArchive@Victoria e-Thesis, 2009. http://hdl.handle.net/10063/1124.

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13

Eriksson, Emma. "Determination of trace elements in thrombocytes by ICP-AES." Thesis, Uppsala universitet, Institutionen för kemi - BMC, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-398044.

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14

Greaves, Mervyn John. "Trace elements in marine biogenic carbonates : analysis and application to past ocean chemistry." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/63291/.

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Trace elements in marine biogenic carbonates may be used as proxies for past ocean chemistry provided that there is an established relationship between the trace element proxy and a parameter of interest, this relationship is preserved within biogenic carbonate, and the trace element can be determined sufficiently accurately. Successful application of any trace element proxy requires both development of the analytical methodology to ensure accurate data with the necessary sensitivity, and an understanding of the relationship between proxy and seawater chemistry. Herein I develop methods for the determination of Mg/Ca, Sr/Ca and Cd/Ca in planktonic foraminiferal calcite, using inductively coupled plasma optical emission spectrophotometry and isotope dilution thermal ionisation mass spectrometry, and propose a potential reference material for Mg/Ca in foraminiferal calcite. The developed techniques are applied to an investigation of the Mg/Ca temperature proxy over Chatham Rise in the Southwest Pacific Ocean and a calibration study of the partition coefficient, DCd, for cadmium incorporation into planktonic foraminifera. Comparisons of planktonic foraminiferal Mg/Ca, shell weight and oxygen isotope records from sites north and south of the Subtropical Front on Chatham Rise, demonstrate the effects of hydrography, foraminiferal habitat and dissolution as controls on Mg/Ca. Determinations of Cd/Ca in seven species of planktonic foraminifera confirm that the dominant controls on Cd/Ca are foraminiferal habitat and hydrography, with only a minor influence of post depositional dissolution. The major uncertainty in determination of DCd from core top samples comes from uncertainty in estimation of the depth distribution and seasons of calcification of planktonic foraminifera.

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15

GRANT, TYRE D. "ASSESSING THE ENVIRONMENTAL AND BIOLOGICAL IMPLICATIONS OF VARIOUS ELEMENTS THROUGH ELEMENTAL SPECIATION USING INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085590907.

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16

Cao, Qianwen. "Mass Balance of Major, Minor and Trace Elements During AFBC Combustion of Fuels." TopSCHOLAR®, 1997. http://digitalcommons.wku.edu/theses/899.

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The proposed ASTM procedures for the determination of 13 major and minor., and 11 trace elements, in solid coal and coke combustion residues by inductively coupled plasma-atomic emission spectrometry (ICP-AES) were checked for routine use. In this study, the ICP analysis values and XRF analysis values of major and minor elements in two kinds of coal and two kinds of limestone were compared. It was shown that over 95% closure of the mass balances of the 24 major, minor, and trace elements was obtained with the proposed ASTM procedure. Also, it was demonstrated that trace elements may be lost through combustion. From six combustion runs, the composition of the fly ashes produced in the FBC burns was determined by XRF analysis. The total carbon, inorganic carbon, and unburned carbon in the fly ashes were also determined. The combustion efficiency of the AFBC system was calculated by comparing the carbonto-iron ratios in the unburned fuel to that in the fly ashes.

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17

Santamaria-Fernandez, Rebeca. "New strategies to determine the distribution of trace elements in soils and sediments." Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/2084.

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Sequential chemical extraction to fractionate metals in soils and sediments into different groups reflecting their "leachability" has been widely employed to determine distribution of metals in different physico-chemical phases. A large number of sequential extraction schemes have been reported, most of them modifications of Tessier's extraction protocol. Although this method has been widely accepted, it is important to highlight that sequential extraction procedures are often tedious and time consuming and that they also suffer from a number of limitations, such as the problem of achieving selective dissolution and the re-adsorption of trace metals during extraction. The objective of this study was to develop, optimise, characterise and apply a novel sequential extraction procedure for the evaluation of trace metal distribution in soils and sediments in order to speed up the process, but more importantly to provide robust data for further aid the chemical characterisation of such samples. The method developed used centrifugation to pass the extractant solution (HNO3) at increasing concentrations, through the soil/sediment sample. The sequential leachates were collected and analysed by ICP-AES for a suite of 18 analytes. The method then utilised chemometrics in order to facilitate processing of the data. Optimisation of the new extraction protocol was performed using an experimental design approach. This was important since the method employed multi-elemental analysis to predict the composition of the physico-chemical phases in a range of soils and sediments. The approach used for data processing was again novel and was based on a simple product of matrices. However many statistical and chemometric approaches are used throughout this thesis to aid both the design of the method and the interpretation of the data obtained. Once optimised, the methodology was evaluated using a range of reference materials and tentative assignments were made in order to characterise the different physico-chemical phases in the soils by comparison with previously obtained data following Tessier's protocol. Significant correlation was obtained for the exchangeable fraction, the fraction associated with carbonates and the iron and manganese oxides fraction. Hence the method proved to be effective in providing Important information in terms of metal distribution in agreement with established procedures. The method was then applied to the study of the effect of humic acids (HA) on trace metal distribution in two different samples. Both samples were spiked with increasing amounts of humic acids and the sequential extraction procedure was used to monitor the changes in metal distribution. Differences when HA were added were found for most of the physico-chemical components in both samples. This provided practical data to support the theoretical assumption that HA interact with the metals present in the soil samples changing their distribution. Using the new method, an evaluation of the trace metal distribution within the Arosa estuary (N.W. Spain) with respect to trace metal contamination was performed. Finally, an on-line automated multisequential extraction system was built "in-house", and coupled with the ICP-AES instrument to allow the fast characterisation of soils and sediment samples. The new system proved to be faster than the batch method and minimised the chance of sample mislabelling, sample contamination etc. Good agreement between results obtained from the on-line method, the batch method, and results using the Tessier scheme was obtained. The automated method clearly offers great potential for a range of environmental pollution studies aiding the quick identication of the physico-chemical components in geochemical samples.

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18

Worrasettapong, Watcharapong. "Ultratrace analysis and speciation studies on trace elements in environmental and biological samples." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269381.

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19

Herselman, J. E. "The concentration of selected trace metals in South African soils /." Link to the online version, 2007. http://hdl.handle.net/10019.1/1390.

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20

McGuire, Sara Anne. "Noxious Smoke and Silent Killers: Identity, Inequality, Health, and Pollutant Exposure During England’s Industrial Revolution." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594403381913239.

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21

Rohman, Joshua. "A Novel Trace Elemental Analysis of Potassium Phosphates." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1459243950.

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22

Savic, Dejan. "Optimization of Microwave-Assisted Acid Digestion Method for Determination of Trace Elements in Coal and Coal Fly Ash." TopSCHOLAR®, 2008. http://digitalcommons.wku.edu/theses/4.

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In most of the analytical and environmental laboratories today inductively coupled plasma (ICP) is a method of choice for analysis of trace metal elements present in coal and coal combustion products. This method requires use of liquid samples, so all coal and coal combustion products must be digested prior to analysis by ICP. Traditionally an open-air hot-plate acid digestion method published as ASTM D6357-04 was used to extract all trace metal elements into solution. Recent development of microwave systems designed for digestions under extreme acidic conditions and high temperatures and pressures shifted focus toward more rapid and precise microwave-assisted digestion of samples. A number of papers have been published involving research efforts toward development of quantitatively satisfying digestion methods. However, there is still no published ASTM or EPA method for microwave-assisted digestion of coal and coal combustion products. The goal of this research is compare the recoveries obtained by using hot plate method with results obtained by microwave-assisted digestion, as well as to attempt to optimize method conditions for latter.

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23

Abou-Shakra, Fadi R. "The determination of lithium and other trace elements in blood serum by ICP-MS." Thesis, University of Surrey, 1991. http://epubs.surrey.ac.uk/843012/.

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Inductively coupled plasma mass spectrometry (ICP-MS) is a powerful tool for elemental analysis and has been used to find the composition of many materials in recent years. This thesis deals with the analytical utility of ICP-MS for the determination of endogenous levels of Li in serum Factors such as the scanned mass range and the dwell time were found to significantly affect the instrument response. Under optimum conditions for Li the serum matrix was found to cause limited non-spectroscopic interferences. Elemental recombinations of the major electrolytes in the matrix did not affect Li determination. However, several biologically important elements e.g. Cr, V, and As were significantly affected by these interferences which limited the usability of the multi-element capabilities of the technique. The feasibility of the analysis of dilute serum was investigated. The results showed that the high levels of proteins in serum caused a rapid deterioration of the magnitude and the stability of the signal. Therefore, a wet digestion technique using HNO3 was devised. The method proved to be accurate and precise not only for Li but also for B, Mg, Co, Cu, Zn, Se, Br, Rb and Cs. International standard reference materials (SRM) were used in order to test the accuracy of the overall procedures. Comparable results to the certified values were obtained for all the elements studied. In addition, this work provided the first data for Li and B in two SRMs, namely, NIST bovine serum and Versieck's second generation serum. The levels of Li in the serum of healthy subjects were evaluated based on the analysis of 196 samples. The data showed that the reference value for Li in serum approximates to 0.9 ng.ml-1. To demonstrate the applicability of this work for biological studies, the levels of Li, B, Mg, Co, Cu, Zn, Se, Br, Rb and Cs were determined in the serum of patients with skin disorders. Several changes in trace element levels e.g. the elevation of Li in polymorphic light eruption were observed. Overall, this study demonstrates the suitability of ICP-MS for routine multi-element analysis of several trace elements in serum. Although matrix dependent problems can be a limiting factor, ICP-MS is likely to become the instrument of choice for routine analysis of biological materials.

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24

Onal, Gulay. "Determination Of Dry Deposition Fluxes Of Trace Elements In An Urban Atmosphere." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605666/index.pdf.

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In this work, dry deposition of metals is investigated in an urban area
city of Ankara using snow as a surrogate surface. Two sampling campaigns were conducted to determine dry deposited amount of 13 species namely
H+, Na, K, Al, Mg, Fe, V, Cd, Cr, Cu, Pb, Zn, Ni. First sampling was performed after a major snow fall in Ankara in January 2001, from 4 points according to a predetermined sampling procedure in order to assess background composition of snow. After 12 days, snow samples were collected from 54 points. All samples are filtered, digested and divided into two aliquots in order to investigate soluble and insoluble fractions separately. Temporal changes of snow showed that snow is a good surrogate surface for dry deposition of metals and provide multifunctional informative data. Pollution maps of the city are drawn using Mapinfo software to investigate spatial pollution distributions. Factor analysis are applied and five main factors for these elements are found, indicating three main sources as traffic, soil and combustion. Enrichment factor calculations showed that Ni, Ca, Pb, Zn, Ni, Cu and Cd are highly enriched pointing out the anthropogenic sources affecting the city atmosphere drastically.

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25

Leitzke, Felipe Padilha [Verfasser]. "Crystal chemistry, melt composition and redox controls on the behavior of trace elements during lunar magmatism / Felipe Padilha Leitzke." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1173789596/34.

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26

Williamson, Latresa J. "Trace Elemental Analysis of Selenium and Antimony Using Hydride Generation Coupled to Laser Induced Breakdown Spectroscopy." Youngstown State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1288009807.

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27

Martins, Lucelene. "Geração e migração de magmas graníticos na crosta continental: estudos de detalhe em granitos e migmatitos da região de Nazaré Paulista (SP)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/44/44135/tde-19042007-155618/.

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As condições de geração e migração de magmas na crosta continental foram investigadas a partir de estudos de detalhe em dois afloramentos de granitos anatéticos tipo Nazaré Paulista (Nappe Socorro Guaxupé, região de Atibaia, SP), utilizando como ferramentas principais a geoquímica de elementos maiores e traços em rochas e minerais e a isotopia Sr-Nd. O granito Nazaré Paulista tem uma ampla variedade composicional, sendo as duas variedades principais um granada leucogranito e um granada-biotita granito cinza com uma rede de vênulas de leucogranito (~625 Ma, U-Pb monazita). Ambos os tipos formam corpos sub-concordantes de dimensões decamétricas nos dois afloramentos; as relações de contato quando observadas indicam a intrusão posterior dos granada leucogranitos. Dois tipos de leucossomas foram reconhecidos em paragnaisses migmatíticos associados aos granitos Nazaré Paulista: (1) granada-biotita tonalito com baixa razão Rb/Sr (0,3), padrões de ETR pouco fracionados ((La/Yb)N = 4-5) e com anomalia negativa de Eu e assinatura isotópica Sr-Nd idêntica à do mesossoma; (2) granada leucogranito, com razão Rb/Sr de ~0,56, padrões de ETR pouco fracionados ((La/Yb)N = 5), com anomalia positiva de Eu e eNd(t) idêntico ao do mesossoma, mas com 87Sr/86Sr(t) mais baixa. Ambos os tipos de leucossomas são distintos dos granitos e foram interpretados como produtos da fusão em presença de água do paragnaisse, respectivamente antes e depois da geração de feldspato potássico no protolito. Alguns contrastes geoquímicos relevantes são observados entre os granitos cinza e os leucogranitos: os primeiros apresentam maior mg# e Zr e padrões de ETR mais fracionados; as razões Rb-Sr de ambos os tipos são semelhantes (0,4-0,7). A assinatura isotópica Sr-Nd dos granitos mostra importante variação (eNd(t) = -16 a -13 e 87Sr/86Sr(t) = 0,716-0,728); apenas duas amostras de leucogranito têm assinatura coincidente com o campo dos paragnaisses regionais. Assumindo os paragnaisses como fonte única dos granitos Nazaré Paulista, é necessário que a fusão tenha ocorrido em desequílibrio e em presença de água. A química de elementos traços em granada foi fundamental para a identificação dos diversos processos de diferenciação que respondem pela variedade de granitos observada. Parte dos granitos cinza carrega um componente restítico, representado por granadas com núcleos ricos em ETRP+Y semelhantes às granadas dos paragnaisses encaixantes. As vênulas de granada leucogranito que cortam o granito cinza são formadas provavelmente pela ?refusão? do mush original durante a rápida ascensão e exibem granadas pobres em ETRP, cujos teores aumentam para a borda, definindo um padrão tipicamente magmático. Os leucogranitos que formam corpos isolados podem em parte corresponder a diferenciados do granito cinza, conforme indicado pelas relações de campo e pela geoquímica de rocha. No entanto os leucogranitos com alta 87Sr/86Sr(t) apresentam granadas com núcleos ricos em ETRP+Y e monazita com composição similar a dos paragnaisses, reforçando a hipótese de serem estes produtos da fusão direta de paragnaisses.
The conditions of melt generation and migration in the continental crust were investigated through a detailed study of two outcrops of the anatectic Nazaré Paulista granites (Socorro-Guaxupé, Nappe, Atibaia region, SE Brazil), using as main tools the rock and mineral major and trace-element geochemistry and Sr-Nd isotopy. The Nazaré Paulista granite shows a wide compositional variation, and can be grouped into two main types: a garnet leucogranite and a veined grey garnet-biotite granite, the latter dated at ~625 Ma (monazite U-Pb ID-TIMS). These types occur as subconcordant bodies 10-50 m wide and are present in both outcrops; where observed, the contact relationships show that the garnet leucogranites intruded after the grey granites. Two types of leucosome were recognized in migmatitic paragneisses associated to the Nazaré Paulista granites: (1) garnet-biotite tonalite with low Rb/Sr (0.3 ), slightly fractionated REE patterns ((La/Yb)N = 4-5) with negative Eu anomalies and Sr-Nd isotope signature identical to that of the mesosome; and (2) garnet leucogranite, with Rb/Sr ~0.56, slightly fractionated REE patterns ((La/Yb)N ~ 5) with positive Eu anomalies, eNd(t) identical to that of the mesosome, but lower 87Sr/86Sr(t). Both leucosomes are different from the granites, and were interpreted as the products of water-present melting of the paragneiss, respectively before and after the crystallization of K-feldspar in the protolith. Some relevant geochemical contrasts are observed between the two types of Nazaré Paulista granites: compared to the leucogranites, the gray granites show greater mg# and Zr and more fractionated REE patterns; the Rb/Sr ratios of both are low (0.4-0.7). The Sr-Nd isotope signature has important variations (eNd(t) = -16 to -13 and 87Sr/86Sr(t) = 0.716-0.728); only two leucogranite samples have signatures that are coincident with the field of the regional paragneisses. Assuming the paragneisses as the only source of the Nazaré Paulista granites would require that melting occurred under disequilibrium and water-present conditions. The trace-element chemistry of garnet was important to identify the differentiation processes that respond for the observed variety of anatectic granites. Part of the gray granites carries a restitic component, represented by ETRP+Y-rich garnet cores that are similar to the garnets from the country-rock paragneisses. The garnet leucogranite veins that cut the gray granite were probably formed by \"partial remelting\" of the original mush during rapid ascent, their idiomorphic garnet crystals have a distinctive composition (low HREE in the cores, increasing slightly to the rims), interpreted as magmatic. Some of the leucogranites forming isolated bodies may have been generated by fractionation from the gray granite, as indicated by field relations and rock geochemistry. On the other hand, the leucogranite with high 87Sr/86Sr(t) has ETRP+Y-rich garnet cores and its monazite is compositionally similar to that of the paragneisses, features indicative that they were probably produced by direct melting of these rocks.

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Chari, Sangeetha. "Hydride Generation and Laser Spectroscopy Techniques for Trace Analytical Measurements of Antimony and Selenium." Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1219424557.

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29

Ponce, de Leon Hill Claudia A. "INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROSCOPY USED IN THE DETERMINATION AND SPECIATION OF TRACE ELEMENTS." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin990645108.

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30

Kollander, Barbro. "Inductively Coupled Plasma Atomic Emission Spectrometry : Exploring the Limits of Different Sample Preparation Strategies." Doctoral thesis, Uppsala universitet, Analytisk kemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150861.

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This thesis describes two different sample preparation strategies for inductively coupled plasma atomic emission spectrometry (ICP-AES), and their ability regarding multi element quantification in complex samples. Sensitivity, repeatability, reproducibility and accuracy were investigated. The aim was to increase the over all efficiency, the speed of analysis, and/or the sensitivity of the analytical method. The intention was to measure analytes with concentrations ranging from ng/g to mg/g simultaneously. The aim was additionally to study chemical and physical processes occurring during the sample preparation, the sample transport to the plasma, and the atomization therein. In the first sample preparation strategy, a hydrophilic highly cross-linked iminodiacetate-agarose adsorbent, IDA-Novarose, was used for preconcentration of metal ions, and matrix elimination in natural water samples. The sorbent was synthesized with different binding capacities. The effect of the capacity on preconcentration, matrix elimination, and uptake capability at high flow rates was studied. For a high capacity IDA-Novarose (≥ 45 µmole/ml) quantitative uptake was seen even at high flow rates (100 ml/min) for Cu2+ with a high affinity to the adsorbent, and for Cd2+ with a moderate affinity. For lower capacities the uptake of Cd2+ was affected by the sample matrix and the flow rate. A method based on the determination of the conditional stability constant of the metal sorbent complex was suggested for the prediction of the sorbent capacity needed to obtain quantitative recovery and optimal matrix elimination. The sorbent was used in a flow system with online buffering for the analysis of a certified riverine water (SLRS-3), tap water and lake water. With few exceptions the results obtained by ICP-AES after preconcentration agreed well with the certified concentrations and results obtained by ICP-MS. The other sample preparation strategy discussed is a method for non digested biological samples from different animal organs for the multi element analysis by ICP-AES. This “mix and measure method” consists of a simple homogenization of the sample with a mixing rod in a small amount of neutral media, followed by dilution and direct measurement with ICP-AES. The total time of analysis is only a few minutes. The ability of this fast method to accurately quantify some elements of toxic, environmental, and/or physiological concern with the lowest possible sample dilution and the highest possible plasma load was evaluated. In 10 % liver slurry Cd, Co, and Sr, at concentration levels around 0.05 µg/g were quantified simultaneously with P and K around 2000 µg/g and with several other elements in between (Al, Ca, Cu, Fe, Mg, Mn, Pb, and Zn). The relative standard deviation of repeated measurements of samples was around 5 - 6 % for regardless of the concentration of the element. The method was also used for fast screening of the elemental distribution in mice organs (brain, heart, kidney, liver, lung and spleen).

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Day, Jason A. "Elemental speciation and trace metal analysis using chemical separations interfaced to inductively coupled plasma - mass spectrometry." Cincinnati, Ohio : University of Cincinnati, 2001. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=ucin991666507.

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32

Lundholm, Karin. "Fate of Cu, Cr, As and some other trace elements during combustion of recovered waste fuels." Doctoral thesis, Umeå : Department of Applied Physics and Electronics, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1132.

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33

DeBord, Joshua S. "Predicting the Geographic Origin of Heroin by Multivariate Analysis of Elemental Composition and Strontium Isotope Ratios." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3802.

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The goal of this research was to aid in the fight against the heroin and opioid epidemic by developing new methodology for heroin provenance determination and forensic sample comparison. Over 400 illicit heroin powder samples were analyzed using quadrupole and high-resolution inductively-coupled plasma mass spectrometry (Q-ICP-MS and HR-ICP-MS) in order to measure and identify elemental contaminants useful for associating heroin samples of common origin and differentiating heroin of different geographic origins. Additionally, 198 heroin samples were analyzed by multi-collector ICP-MS (MC-ICP-MS) to measure radiogenic strontium isotope ratios (87Sr/86Sr) with high-precision for heroin provenance determination, for the first time. Supervised discriminant analysis models were constructed to predict heroin origin using elemental composition. The model was able to correctly associate 88% of the samples to their region of origin. When 87Sr/86Sr data were combined with Q-ICP-MS elemental data, the correct association of heroin samples improved to ≥90% for all groups with an average of 93% correct classification. For forensic sample comparisons, quantitative elemental data (11 elements measured) from 120 samples, 30 from each of the four regions, were compared in order to assess the rate of discrimination (5400 total comparisons). Using a match criterion of ±3 standard deviations about the mean, only 14 of the 5400 possible comparison pairs were not discriminated resulting in a discrimination rate of 99.7%. For determining the rate of correct associations, 3 replicates of 24 duplicate samples were prepared and analyzed on separate days. Only 1 of the 24 correct pairs were not associated for a correct association rate of 95.8%. New methods for provenance determination and sample comparison are expected to be incredibly useful to intelligence agencies and law enforcement working to reduce the proliferation of heroin.

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34

Saqib, Naeem. "Distribution and chemical association of trace elements in incinerator residues and mining waste from a leaching perspective." Doctoral thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-48933.

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Incineration is a mainstream strategy for solid waste management in Sweden and all over the world. Improved knowledge and understanding about the distribution of trace elements (in ashes) during incineration, and how trace element partitioning respond to the changes in waste composition, are important in terms of combustion process optimization and plant efficiency. Moreover, determination of chemical association of trace elements in ashes are vital for avoiding environmental concerns and to promote possible reuse. In this study, partitioning of trace elements in ashes during incineration as function of input waste fuel and incineration technology was investigated. Further, chemical association of trace elements in resulting ashes was studied. An evaluation was also performed about feasibility of metal extraction from sulfidic mining waste and flotation tailings. Moreover, green liquor dreg (GLD) was tested with respect to stabilization of metals within the sulfidic mining waste. Findings showed that the total input of trace elements and chlorine affects the partitioning and increasing chlorine in the input waste caused increase in transfer of trace elements to fly ash especially for lead and zinc. Vaporization, condensation on fly ash particles and adsorption mechanisms play an important role for metal distribution. Firing mixed waste, especially biofuel mix, in grate or fluidized (CFB) boilers caused increased transfer into fly ash for almost all trace elements particularly lead and zinc. Possible reasons might be either an increased input concentration of respective element in the waste fuel, or a change in volatilization behavior due to the addition of certain waste fractions. Chemical association study for fly ashes indicated that overall, Cd, Pb, Zn, Cu and Sb are presenting major risk in most of the fly ashes, while in bottom ashes, most of elements are associated with stable fraction. Further, fuel type affects the association of elements in ashes. Chemical leaching of mining waste materials showed that sulfuric acid (under different conditions) is the best reagent to recover zinc and copper from sulfidic mining waste and also copper from flotation tailings. GLD indicates potential for metal stabilization in mining waste by reducing the metal mobility. Extraction methods could be applied to treat mining waste in order to meet the regulatory level at a specific mining site.Similarly stabilization/solidification methods might be applied after leaching for recovery of metals.

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Herselman, Jacoba Elizabeth. "The concentration of selected trace metals in South African soils." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1390.

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Thesis (PhD (Soil Science))--University of Stellenbosch, 2007.
Trace elements occur naturally in soils, usually at low concentrations (<0.1% or <1000 mg kg-1 of the earth’s crust), as a result of weathering and pedogenic processes acting on the rock fragments from which soil develops (parent material). Since about 98% of human food is produced on land, soil is the primary source supplying these elements to the food chain. Although cases of trace element deficiency and toxicity have been documented in many parts of South Africa, no comprehensive description of trace element concentration has yet been attempted for South Africa as a whole. The Natural Resources Land Type mapping project, initiated in the mid-1970s, has provided a collection of samples (approximately 4500) from soil profiles selected to represent the main soil forms in each land type and therefore to provide representative coverage of most of the soils of South Africa. These archived samples have now been analysed for a spectrum of trace elements, in terms of both available and total concentrations as well as other soil properties. Although detailed information is available on a wide range of trace metals, the seven trace metals considered to be of most interest in a South African context due to natural geological occurrences were selected for this study, including Cd, Co, Cr, Cu, Pb, Ni and Zn. This data was used to: • determine baseline concentrations in SA soils; • determining threshold values for South African agricultural soils receiving sewage sludge at agronomic rates; • determining the influence of certain soil properties on the baseline concentrations of these trace elements in SA soils; and • development of a bioavailable trace element distribution map for SA. The range, the mean and standard deviation (both arithmetic and geometric), and the median were used to summarize the data statistically. The baseline concentration range was calculated using the quotient and product of the geometric mean and the square of the geometric standard deviation, including data below the instrument detection limit. The upper limit of the baseline concentration range was set at the 0.975 percentile value of the population in order to minimize the influence of contamination and the lower limit at the 0.025 percentile value to minimize problems that might be associated with analytical uncertainty near the lower limit of detection. The quantile regression statistical approach was followed to illustrate the relationship between soil properties and trace element concentrations in soils. The soil properties that showed the strongest relation were CEC, clay content, pH (H2O) and S value (base status). The soils were then divided into different classes according to these soil properties and baseline concentrations were derived for the different classes. Soils with low clay contents have lower trace element concentrations than soils with higher clay contents, soils with low or high pH levels have lower trace element contents than soils with intermediate pH values and mesotrophic soils have higher trace element concentrations than dystrophic soils. This information is useful for the compilation of trace element distribution maps for South Africa where different soil forms and series/families could be classified into different classes to determine areas of potential deficiencies as well as toxicities. South Africa, with its diverse geology, has areas of both trace element toxicities and deficiencies and for decision-making purposes it is necessary to identify these areas. Mapping of trace element levels based on soil samples would provide valuable information, which cannot be obtained from geological or geographical maps. Statistical analyses of the data (clay %, base status, pH (H2O) and NH4EDTA extractable trace element concentrations) indicated that soils could be divided into five trace element classes based on their clay content, pH and base status (dystrophic, mesotrophic and eutrophic). The soil series according to the binomial soil classification system for South Africa were then divided into these different classes. The geometric means for each clay class were determined and the baseline concentration range for each class was calculated. The land type maps were used as basis for the distribution maps. A general trace element distribution map for South Africa was derived from this data as well as Cu and Zn distribution maps. A random selection of 500 soil samples across the country was used to verify the accuracy of the distribution map. The general trace element distribution map indicate, with a confidence level between 89 and 96%, where the potentially available trace element content of South African soils are low (deficient) too moderately high, excluding rocky areas and areas with limited soil. The Cu and Zn maps indicate the distribution and expected baseline concentrations of these specific elements in South African soils. The same methodology could be applied to derive risk maps for all the individual trace elements to indicate the distribution and expected baseline concentrations of the elements in South Africa. This presentation of baseline concentrations, reflecting likely natural ranges in South African soils, is the first quantitative report on the spatial extent and intensity of Zn, Cu and Co deficiency in South African soils. The proposal of new threshold values for trace elements in agricultural soils will be valuable in setting more realistic norms for environmental contamination that accommodate the geochemical peculiarities of the region, one example being rather high Cr and Ni concentrations with low bio-availability. This information should be of value not only in environmental pollution studies but also in health, agriculture, forestry and wildlife management. The following recommendations are made: • The baseline concentrations could be used to determine site specific threshold values based on soil properties and soil type. Soils with lower pH, clay content and CEC would require more protection than soils with high pH, clay content and CEC and therefore the threshold levels for these soils should be lower. • Although the distribution maps can be used to indicate broad areas of trace element deficiencies and toxicities, more detailed investigations are recommended for areas where problems are experienced. The same methodology could be applied on smaller scale to increase the value of the map and to add more value on a regional scale. The maps could be used for regional soil quality assessment especially in areas where trace element deficiencies or toxicities could result in negative effects on plants and animals.

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36

Ferreira, Guilherme Gonçalves Pereira da Silva 1981. "Medição do aporte atmosférico dos elementos-traço nos municípios de Campinas e Paulínia com auxílio da espécie vegetal Tillanásia usneoides (L.)." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286756.

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Orientador: Jacinta Enzweiler
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências
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Resumo: A bromélia epífita Tillandsia usneoides (L.) foi utilizada para realizar um biomonitoramento atmosférico em sete locais ao longo de uma transecta que passa pelos municípios de Campinas e Paulínia. Os pontos escolhidos situam-se próximos a rodovias, indústrias e avenidas, assim como em locais mais afastados de atividades antrópicas. Amostras da planta foram introduzidas por aproximadamente dois meses em cada um locais durante cinco intervalos sequenciais, entre abril de 2009 e março de 2010. Os objetivos foram conhecer a distribuição sazonal e espacial das concentrações de elementos-traço (Al, Ba, Bi, Cd, Co, Cu, Cr, Fe, Ga, Hf, Ni, Nb, Pb, Rb, Sb, Sn, Sr, Ti, Sr, Ce, Pr, V, Y e W), estabelecer relações com dados climáticos e parâmetros de qualidade do ar e estimar as fontes a partir dos aportes medidos. Após o período de exposição, as amostras da planta foram removidas, liofilizadas e moídas. Uma alíquota foi dissolvida em meio ácido (HNO3 e HF destilados) e analisada em espectrômetro de massas com plasma indutivamente acoplado (ICP-MS). O material de referência certificado de folhas de macieira NIST 1515 foi analisado para o controle da qualidade. Os resultados das concentrações obtidas de cada elemento nas amostras expostas foram normalizados em relação a amostras-controle, não expostas, para obter um Coeficiente de Enriquecimento (CE). Os maiores aportes de elementos-traço foram identificados nos meses de abril-junho/09, setembro/09-novembro/09 e janeiro/10-março/10, atribuídos à presença de maiores concentrações de material particulado e de poluentes na atmosfera, além de fatores climáticos não favoráveis a sua dispersão nesses períodos. Os menores coeficientes de enriquecimento obtidos para o período de maior pluviosidade - novembro/09-dezembro/10 - foram atribuídos à remoção parcial dos poluentes por deposição úmida. O maior aporte total foi medido no ponto CSC (Careca Sport Center), e os elementos que apresentaram maiores CE foram Al, Cr, Co, Ni, Y, W, Ce e Pr. A principal fonte para esses resultados provavelmente é a poeira do solo, e secundariamente o tráfego de veículos e emissões de indústrias próximas. No ponto FEAGRI (no campus da Unicamp) um conjunto de elementos, entre eles Ni e Co, apresentou CE relativamente elevados, e que foram atribuídos principalmente à poeira do solo local. O ponto CENTRO (centro de Campinas) apresentou os maiores CE de Ba, Sn, Cu e Sb, com aportes Pb, Cd, Bi, Al, Fe, Ga, Nb, Ti também elevados, associados principalmente ao tráfego de veículos. Nos pontos de Paulínia aportes relativamente elevados foram medidos para Ba, Sb, Bi e V e que foram associados ao tráfego e indústrias na região, incluindo as petroquímicas. Os pontos CABRAS e MSG, mais distantes de influências antrópicas, apresentaram as menores concentrações de metais poluentes em razão da distância relativa às fontes e ao posicionamento favorável quanto à direção dos ventos principais, respectivamente. Os dados obtidos sugerem que os aportes estão associados a fontes locais e ao transporte de curta distância por ventos NO, enquanto o transporte de longa distância por ventos sudeste, não foi confirmado
Abstract: The epiphytic bromeliad Tillandsia usneoides (L.) was used as biomonitor of the atmosphere at seven sites along a transect of the municipalities of Campinas and Paulinia. The selected sites are located near highways, industries and avenues, as well as in places farther away from human activities. The samples of were introduced by about two months during five sequential intervals, from April 2009 to March 2010. The goals were to know the seasonal and spatial concentrations of trace metals (Al, Ba, Bi, Cd, Co, Cu, Cr, Fe, Ga, Hf, Ni, Nb, Pb, Rb, Sb, Sn, Sr, Ti, Sr, Ce, Pr, V, Y e W), establish relationships with climatic data and parameters of air quality and estimate the sources of the deposition. After the exposure period, the plants samples were taken to the laboratory, freeze dried and ground. An aliquot was dissolved (HNO3 plus HF, purified by sub-boiling), and analyzed by inductively coupled plasma mass spectrometry (ICPMS). The certified reference material Apple Leaves NIST SRM 1515 was analyzed for quality control. The measured concentrations of exposed plants were normalized against control samples of non exposed plants to obtain the coefficient of enrichment (CE). The largest inputs of traceelements were identified in April-June/09, September-November/09 and January-March/10, which are also the periods with higher concentrations of particulate matter and pollutants in atmosphere together with less favorable climatic factors to their dispersion. The lowest CE values in November/09-January/10 were attributed to the partial removal of atmospheric pollutants by wet deposition. The highest depositions was measured at CSC (Careca Sport Center) and Al, Cr, Co, Ni, Y, W, Ce e Pr showed high CE. The main sources for such results probably are soil dust, nearby traffic and industrial emissions. At FEAGRI (at Unicamp campus) a set of elements, including Co and Ni, presented relatively high CE, which were attributed mainly to dust from local soil. The site at Campinas downtown presented the highest CE of Ba, Sn, Cu and Sb, and also significant input of Pb, Cd, Bi, Al, Fe, Ga, Nb, Ti mainly due to the traffic of vehicles. At the sites in Paulínia, relatively high CE were obtained for Ba, Sb, Bi e V, which were associated to traffic and industrial sources. The sites CABRAS and MSG presented the lowest concentrations of metallic pollutants, because they are favored by the distance from anthropogenic sources and the position regarding the direction of main winds, respectively. The data suggest that the deposition of metallic elements is related to local sources and to short distance transport by NW wind, while long distance transport by SE winds was not confirmed
Mestrado
Geologia e Recursos Naturais
Mestre em Geociências

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37

KANNAMKUMARATH, SASI S. "TRACE ELEMENTAL SPECIATION USING CHROMATOGRAPHY/CAPILLARY ELECTROPHORESIS COUPLED TO INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR FOOD, PHARMACEUTICAL AND ENVIRONMENTAL ANALYSIS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085673299.

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38

May, Christopher David. "Development of novel analytical and interpretational protocols to facilitate the provenance establishment of glass and plastic evidence." University of Western Australia. Centre for Forensic Science, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0169.

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[Truncated abstract] The analysis and subsequent interpretation of trace evidence is of paramount importance to the forensic scientist. While a variety of methods are available to facilitate comparison between recovered and control samples, the use of a specific analytical method depends upon both the physical and chemical nature of the material itself and the material to which it is to be compared. Elemental analysis of evidentiary material is one such method of sample comparison and has been extensively applied to this purpose following the introduction of neutron activation analysis in the early 1960s. However, over the last 15 years, another instrumental technique has taken centre stage in the analytical armoury of the forensic scientist: laser ablationinductively coupled plasma-mass spectrometry (LA-ICP-MS). The modification and adaptation of this technique, to a point where it is possible to distinguish between glass materials produced only hours apart on the same production line, is detailed in this thesis. Additional protocols have also been developed for the analysis of fibreglass and plastic crime scene debris. Finally, a method for quantification of elemental concentrations in headlamp plastics has also been developed to facilitate inter-comparison of data between both different analytical techniques and different laboratories. Glass material is one of the most common varieties of trace evidence and the forensic examination of glass traditionally involves the determination of its refractive index (RI). ... The analytical protocol involves the analysis of 46 analytes on material comprising the exterior surface of the lens. Using this data, it was found that although minor variations in elemental composition exist within a single headlamp lens, discrimination between lenses produced from a single manufacturing plant over a short period of time could still be achieved. Discrimination between all headlamp lenses, with the exception of some lenses produced on the same day, could be facilitated using the analytical protocol developed. Furthermore, an interpretational protocol has been developed that has successfully classified all unknown headlamp lens samples investigated in this study, within the discrimination limits of the analytical method. The semi-quantitative analysis of glass and plastic samples has also been examined using LA-ICP-MS. The concentrations of 16 analytes in container and float glass samples were determined. However, the levels of discrimination afforded by the semi-quantitative data were inferior to those achieved using qualitative data. Finally, a series of plastic-based standards, containing 25 analytes of known concentrations, was produced. Using these standards, relative concentrations of the study analytes were determined in polycarbonate headlamp lenses. Interpretation of the data produced made it possible to discriminate between all study samples. Consequently, the total analytical and interpretational protocol developed in this study has established the foundation for LA-ICP-MS to be adopted internationally as a recognised method for the analysis of plastic crime scene debris.

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German, Laura Lynne. "The Geochemical Evolution of the Blood Falls Hypersaline System." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1438715896.

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40

Hanley, Traci A. "Trace Elemental Methodologies for the Chromatographic Speciation of Silver Ions and Silver Nanoparticles and the Development of Rice Flour Internal Quality Control Material for Arsenic Speciation Applications using High Performance Liquid Chromatography." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491898753606019.

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41

Boman, Christoffer. "Particulate and gaseous emissions from residential biomass combustion." Doctoral thesis, Umeå : Univ, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-501.

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42

Rolls, Holly Jacqueline. "Using Otolith Elemental Composition to Track the Habitat Use, Movements, and Life History Patterns of Common Snook (Centropomus undecimalis) and Red Drum (Sciaenops ocellatus) in the Tampa Bay Estuary." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5298.

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Knowledge of fish habitat use and connectivity is critical for understanding the structure and dynamics of fish populations and, therefore, necessary for the implementation of successful fisheries management strategies. Tagging is an effective means of providing such information, and the elemental composition contained within fish otoliths is increasingly being used as a natural tag. The chemical composition of otoliths reflects the incorporation of elements from different water bodies and can thus be used to understand the habitat use, movements, and life history patterns of fishes. To assess the applicability of otolith elemental composition as a tagging technique within the Tampa Bay estuary, Florida, laser ablation-inductively coupled-plasma mass spectrometry (LA-ICP-MS) was used to analyze the elemental composition of otoliths from two estuarine-dependent fish species, Snook (Centropomus undecimalis) and Red Drum (Sciaenops ocellatus). Otolith elemental fingerprints can be used to quantify the proportion of juveniles from different nurseries that survive to join the sub-adult and adult fisheries, thus, providing resource managers with quantitative criteria to prioritize the most productive areas for conservation and restoration. To evaluate the use of otolith elemental fingerprinting in the Tampa Bay estuary, the spatial and temporal scales of chemical variation in otoliths collected from throughout Tampa Bay were examined by performing permutation-based multivariate analyses of variance (MANOVA) on the elemental data at several spatial (individual tributary, two-region, and three-region) and temporal (annual and seasonal) scales. Canonical Analysis of Principal Coordinates (CAP) was used to generate classifiers based on the otolith elemental fingerprints of juvenile fish, and `leave-one-out' cross-validation procedures indicated that the greatest classification accuracy was obtained by using the two-region model (upper vs. lower Tampa Bay) for both species (for Snook F=45.8, p=0.001, CAP cross-validation success=76%; for Red Drum F=9.7, p=0.001, CAP cross-validation success=87%). For both species, all temporal analyses at the inter-annual scale indicated that otolith elemental fingerprints were significantly different across years (two-way MANOVA; p Several environmental factors which may have contributed to the regional differences in otolith chemistry were examined, including physico-chemical parameters (surface measurements of salinity, dissolved oxygen, pH, and temperature taken at the time of sample collection), surficial geologic stratigraphy, and land development. Weak, but significant correlations were identified between some elements and physico-chemical parameters; however, instantaneous measurements taken at the time of fish collection may not have provided an accurate representation of the overall conditions experienced by the fish during the period in which the otolith material used in analyses had been deposited (2 - 4 weeks). A significant correlation between latitude and otolith Sr/Ca was found, likely corresponding to an increasing ambient gradient that occurs from the upper to lower bay (for Red Drum F=77.1, p=0.001; for Snook F=69.2, p=0.001). The Land Development Intensity metric was negatively correlated with otolith Li/Ca and Sr/Ca. While surficial geologic inputs may have also contributed to the elemental composition of otoliths, the relationships revealed by redundancy analyses (RDA) were somewhat unclear or contradictory. Once the appropriate chemical characterization of the study area was identified (the two-region models for both species), elemental fingerprints from the core portions of sub-adult and adult otoliths were assigned to their most probable juvenile habitat region using a maximum likelihood estimator based on the posterior probabilities generated by CAP analyses (CAP-MLE). Application of the two-region model revealed that the majority of Red Drum (83%) was determined to have originated from juvenile habitats in the upper Tampa Bay region, while most Snook (60%) originated from juvenile habitats in the lower Tampa Bay region. The majority of sub-adult/adult Snook and Red Drum were collected from the same region in which they were determined to have originated (for Snook, 36 out of 55 = 65%; for Red Drum, 58 out of 78 = 74%), indicating some level of site fidelity to juvenile habitat areas. The use of otolith elemental profiling to reconstruct specific environmental and physiological experiences has the potential to provide unique insights regarding the life histories of Snook, a species with unpredictable spawning and movement characteristics. Otoliths from Snook maintained in captivity at the Mote Aquaculture Park (MAP) were analyzed to elucidate the degree to which various factors, including otolith growth (macrostructure features), spawning events, handling stress, and salinity influence otolith chemistry. Cross-correlation analyses of otolith elemental profiles and quantified macrostructure features (including annuli and checks) demonstrated that interpretations of elemental patterns should not be confounded by changes associated with otolith crystallography. An elemental marker for known spawning events was not identified (ANOVA spawners vs. non-spawners, p>0.05); however, because the physiological costs and alterations in blood chemistry associated with gonadal maturation (rather than the singular act of spawning) could affect otolith chemistry, additional studies which more thoroughly track maturation stages may be able to identify a suite of elements that can be used to discern the reproductive histories of Snook. Significantly elevated Zn:Ca (ANOVA: F=5.64, p=0.012) and decreased Fe:Ca (ANOVA: F=25.02, p Continuous life history Ba:Ca and Sr:Ca profiles of 56 wild Snook collected from throughout Tampa Bay revealed significant plasticity in the types of juvenile habitats settled, as well as in the timing of ontogenetic movements from these habitats. Of the profiles examined, 55% exhibited otolith core signatures characterized by an opposing Sr:Ca and Ba:Ca pattern, followed by an inverted pattern, providing an indicator of the movement of larvae from high salinity, pre-settlement environments into mesohaline, tidally-influenced juvenile habitats. In contrast, nearly half (45%) the Sr:Ca and Ba:Ca profiles indicated settlement in higher salinity environments, suggesting a high degree of habitat plasticity for juveniles of this species. For fish that settled into mesohaline habitats, decreases in Ba:Ca and/or increases in Sr:Ca over the first several years of life signaled the ontogenetic transition out of the juvenile habitat, with the timing of emergence ranging from within the first year to age-3. Because conditions during early life may propagate into divergent behaviors in subsequent life stages, information on the experiences of early life and juvenile stages could help to inform whether the occupation of different juvenile habitat types, or the precocious or delayed emergence from those habitats, explain the peculiar spawning and movement habits that occur in this species.

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Hartung, Eva. "Early magmatism and the formation of a ‘Daly Gap’ at Akaroa Shield Volcano, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2011. http://hdl.handle.net/10092/5584.

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The origin of compositional gaps in volcanic deposits remains controversial. In Akaroa Volcano (9.6 to 8.6 Ma), New Zealand, a dramatic compositional gap exists between basaltic and trachytic magmas. Previously, the formation of more evolved magmas has been ascribed to crustal melting. However, the interpretation of new major and trace element analysis from minerals and bulk-rocks coupled with the mechanics of crystal-liquid separation offers an alternative explanation that alleviates the thermal restrictions required for crustal melting models. In a two-stage model, major and trace element trends can be reproduced by polybaric crystal fractionation from dry melts (less than 0.5 wt.% H2O) at the QFM buffer. In the first stage, picritic basalts are separated from an olivine-pyroxene dominant mush near the crust-mantle boundary (9 to 10 kbar). Ascending magmas stagnated at mid-crustal levels (5 to 6 kbar) and fractionated an olivine-plagioclase assemblage to produce the alkali basalt-hawaiite trend. In the second stage, trachyte melt is extracted from a crystal mush of hawaiite to mugearite composition at mid-to-upper crustal levels (3 to 5 kbar) after the melt has crystallised 50 vol.%. The fractionated assemblage of plagioclase, olivine, clinopyroxene, magnetite, and apatite is left in a cumulate residue which corresponds to the mineral assemblage of sampled ultramafic enclaves. The results of trace element modelling of Rayleigh fractionation using this extraction window is in close agreement with the concentrations measured in trachyte (= liquid) and enclaves (= cumulate residue). The compositional gap observed in the bulk-rock data of eruptive products is not recorded in the feldspar data, which show a complete solid solution from basalt and co-magmatic enclaves to trachyte. Complexly zoned plagioclases further suggest episodical magma recharge events of hotter, more mafic magmas, which lead to vigorous convection and magma mixing. In summary, these models indicate that the Daly Gap of Akaroa Volcano formed by punctuated melt extraction from a crystal mush at the brittle-ductile transition.

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Lemaire, Jérémy. "Mercury contamination in caimans from French Guiana, bioaccumulation and physiological effects." Thesis, La Rochelle, 2021. https://tel.archives-ouvertes.fr/tel-03716076.

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Le mercure (Hg) est un contaminant environnemental qui affecte tous les écosystèmes. Il a la particularité de se biomagnifier le long de la chaîne trophique et de se bioaccumuler dans les tissus des prédateurs. Le Hg est connu pour avoir des effets néfastes chez les humains et la faune sauvage. Les prédateurs des écosystèmes tropicaux sont particulièrement affectés par la contamination en Hg du fait de l’exploitation aurifère artisanale qui utilise d’importantes quantités de Hg pour extraire l’or. Les crocodiliens sont des super-prédateurs des écosystèmes tropicaux et ils accumulent de fortes concentrations de Hg dans leurs tissus. Ils sont potentiellement de bons candidats pour suivre la contamination en Hg, ce sont des animaux vivant plusieurs décennies, ils ont un métabolisme lent et un taux de conversion de l’énergie important, ce qui favorise la bioaccumulation. De plus, ils ont une répartition importante dans les écosystèmes tropicaux et subtropicaux, ce qui rend la surveillance du Hg possible à large échelle. Mes travaux de doctorat s’intéressent aux quatre espèces de caïmans présents en Guyane (le caïman noir Melanosuchus niger, le caïman nain de Cuvier Paleosuchus palpebrosus, le caïman de Schneider Paleosuchus trigonatus et le caïman à lunettes Caiman crocodilus). J’ai travaillé sur les variations de Hg entre différents tissus obtenus par méthode de prélèvement peu invasif et, j’ai étudié l’influence de la morphologie et de l’écologie trophique (via les isotopes stables) des individus sur les concentrations en Hg. Ensuite, j’ai étudié l’impact d’une contamination en Hg sur les mécanismes physiologiques, le transfert maternel et ses effets sur les nouveau-nés
Mercury (Hg) is a global environmental contaminant that affects ecosystems. It has the particularity to biomagnify through the food web, and to bioaccumulate especially in tissues of top predators. Mercury has been identified to have detrimental effects on human and wildlife. Top predators from tropical ecosystems are particularly affected by Hg contamination due to artisanal small scale gold mining, which uses massive amounts of Hg in the gold extraction process. Crocodilians are top predators of tropical ecosystems and have been identified to accumulate high concentrations of Hg in their tissues. They are potentially good candidates to monitor Hg contamination, as they are long-living animals with low metabolic, and high tissue conversion rates, which favours the bioaccumulation of Hg. Additionally, they have a large repartition over tropical and sub-tropical ecosystems, which make large-scale Hg evaluation possible. My doctoral work focuses on the four caiman species that are present in French Guiana (the Black caiman Melanosuchus niger, the Dwarf caiman Paleosuchus palpebrosus, the Smooth-fronted caiman Paleosuchus trigonatus and the Spectacled caiman Caiman crocodilus). First, I have worked on Hg variation across different tissues obtained by minimally invasive methods, and investigated the influence of morphology and feeding ecology (by using stable isotope method) on Hg contamination in caimans. Second, I have investigated the impact of Hg contamination on physiological mechanisms, and the maternal transfer and its effects on neonates

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45

Hansen, James W. L. "The petrology, geochemistry and petrogenesis of the Goomboorian intrusive complex, southeast Queensland." Thesis, Queensland University of Technology, 1997.

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46

Akinyemi, Segun Ajayi. "Geochemical and mineralogical evaluation of toxic contaminants mobility in weathered coal fly ash: as a case study, Tutuka dump site, South Africa." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1226_1360593017.

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The management and disposal of huge volumes of coal combustion by products such as fly ash has constituted a major challenge to the environment. In most cases due to the inadequate alternative use of coal fly ash, the discarded waste is stored in holding ponds, slag heaps, or stock piled in ash dumps. This practice has raised concerns on the prospect of inorganic metals release to the surface and groundwater in the vicinity of the ash dump. Acceptable scientific studies are lacking to determine the best ash disposal practices. Moreover, knowledge about the mobility patterns of inorganic species as a function of mineralogical association or pH susceptibility of the dry disposed ash dump under natural weathering conditions are scarce in the literature. Fundamental understanding of chemical interactions of dry disposed ash with ingressed CO2 from atmosphere, percolating rain water and brine irrigation within ash disposal sites were seen as key areas requiring investigation. The mineralogical association of inorganic species in the dry disposed ash cores can be identified and quantified. This would provide a basis for understanding of chemical weathering, mineralogical transformations or mobility patterns of these inorganic species in the dry ash disposal scenario. The current study therefore aims to provide a comprehensive characterisation of weathered dry disposed ash cores, to reveal mobility patterns of chemical species as a function of depth and age of ash, with a view to assessing the potential environmental impacts. Fifty-nine samples were taken from 3 drilled cores obtained respectively from the 1 year, 8 year and 20-year-old sections of sequentially dumped,
weathered, dry disposed ash in an ash dump site at Tutuka - a South African coal burning power station. The core samples were characterized using standard analytical procedures viz: X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) techniques, Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and Acid neutralisation capacity (ANC) test. A modified sequential extraction (SE) method was used in this study. The chemical partitioning, mobility and weathering patterns in 1 year, 8 year and 20-year-old sections of the ash dump were respectively investigated using this modified sequential extraction scheme. The sequence of the extractions was as follows: (1) water soluble, (2) exchangeable, (3) carbonate, (4) iron and manganese and (5) residual. The results obtained from the 5 steps sequential extraction scheme were validated with the total metal content of the original sample using mass balance method. The distribution of major and trace elements in the different liquid fractions obtained after each step of sequential extraction of the 59 drilled core samples was determined by inductively coupled plasma mass spectrometry (ICPMS). The data generated for various ash core samples were explored for the systematic analysis of mineralogical transformation and change in ash chemistry with ageing of the ash. Furthermore, the data was analyzed to reveal the impact of ingressed CO2 from atmosphere, infiltrating rain water and brine irrigation on the chemistry of ash core samples. Major mineral phases in original ash core samples prior to extraction are quartz (SiO2) and mullite (3Al2O3·
2SiO2). Other minor mineral phases identified were hematite (Fe2O3), calcite (CaCO3), lime (CaO), anorthite (CaAl2Si2O8), mica (Ca (Mg, Al)3 (Al3Si) O10 (OH)2), and enstatite (Mg2Si2O6). X-ray diffraction results show significant loss of crystallinity in the older ash cores. The presence of minor phases of calcite and mica in dry disposed ash cores are attributed to reduction in the pore water pH due to hydration, carbonation and pozzolanic reactions. The X-ray diffraction technique was unable to detect Fe-oxyhydroxide phase and morealuminosilicate phases in ash core samples due to their low abundance and amorphous character. X-ray fluorescence results of the original ash core samples showed the presence of major oxides, such as SiO2, Al2O3, Fe2O3, while CaO, K2O, TiO2, Na2O, MnO, MgO, P2O5, and SO3 occur in minor concentrations. The ratio of SiO2/Al2O3 classified the original core samples prior to extraction as a silico-aluminate class F fly ash. The ternary plot of major elements in 1-year-old ash core samples was both sialic and ferrocalsialic but 8 year and 20-year-old ash core samples were sialic in chemical composition. It is noteworthy that the mass % of SiO2 varies through the depth of the core with an increase of nearly 3 %, to 58 mass % of SiO2 at a depth of 6 m in the 1-year-old core whereas in the case of the 8-year-old core a 2 % increase of SiO2 to a level of 57.5 mass % can be observed at levels between 4-8 m, showing dissolution of major components in the matrix of older ash cores.. The Na2O content of the Tutuka ash cores was low and varied between 0.6-1.1 mass % for 1-year-old ash cores to around 0.6-0.8 mass % for 8-year-old ash cores. Sodium levels were higher in 1-year-old ash cores compared to 8 year and 20-year-old ashcores. Observed trends indicate that quick weathering of the ash (within a year) leached out Na+ from the ash dump. No evidence of Na+ encapsulation even though the ash dump was brine irrigated. Thus the dry disposal ash placement method does not result in a sustainable salt sink for Na-containing species over time. The total content of each of the elements in 1 year and 20-year-old ash cores was normalised with their total content in fresh ash from same power station to show enrichment and depletion factor. Major elements such as K+, Mn showed enrichment in 1-year-old ash cores whereas Al, Si, Na+, Ti, Ca, Mg, S and Fe showed depletion due to over time erosion. Trace elements such as Cr, Sr, P, Ba, Pb, V and Zn showed enrichment but Ni, Y, Zr showed depletion attributed to over time erosion. In 20-year-old ash cores, major elements such as Al, Na+ and Mn showed enrichment while Si, K+, Fe, Mg and Ca showed depletion highlighting their mobility. Trends indicated intensive flushing of major soluble components such as buffering constituents (CaO) by percolating rain water. The 1-year-old and 20-year-old coal ash cores showed a lower pH and greater loss/depletion of the soluble buffering constituents than the 2-week-old placed ash, indicating significant chemical weathering within a year. Based
on ANC results the leaching behaviours of Ca, Mg, Na+, K+, Se, Cr, and Sr were found to be controlled by the pH of the leachant indicating high mobility of major soluble species in the ash cores when in contact with slightly acid rain water. Other investigated toxic metals such as As, Mo and Pb showed amphoteric behaviour with respect to the pH of the leachant. Chemical alterations and formation of transient minor secondary mineral phases was found to have a significant effect on the acid susceptibility and depletion pattern of chemical species in the core ash samples when compared to fresh ash. These ANC results correlated well with the data generated from the sequential extraction scheme. Based on sequential extraction results elements, showed noticeable mobility in the water soluble, exchangeable and carbonate fractions due to adsorption and desorption caused by variations in the pore water pH. In contrast, slight mobility of elements in the Fe and Mn, and residual fractions of dry disposed fly ashes are attributed to the co-precipitation and dissolution of minor amount of less soluble secondary phase overtime. The 1-year-old dry disposed ash cores were the least weathered among the 3 drilled ash cores. Therefore low concentration of toxic metals in older ash cores were ascribed to extensive weathering with slower release from residual mineral phases over time. Elements were found to associate with different mineral phases depending on the age or depth of the core samples showing greater heterogeneity in dispersion. For instance the average amount of total calcium in different mineral associations of 1-year-old ash cores is as follows
water soluble (10.2 %), exchangeable (37.04 %), carbonate (37.9 %), Fe and Mn (7.1 %) and residual (2.97 %). The amount of total Na+ in different mineral phases of 1-year-old ash cores followed this trend: water soluble (21 %), exchangeable (11.26 %), carbonate (2.6 %), Fe and Mn (4.7 %) and residual (53.9 %). The non-leachable portion of the total Na+ content (namely that contained in the residual fraction) in the 1-year-old ash core samples under conditions found in nature ranged between 5-91 %. This non-leachable portion of the Na+ showed the metastability of the mineral phases with which residual Na+ associates. Results showed older ash cores are enriched in toxic elements. Toxic elements such as As, B, Cr, Mo and Pb are enriched in the residual fraction of older ash cores. For instance As concentration in the residual fraction varied between 0.0003- 0.00043 mg kg-1 for 1-year-old ash cores to around 0.0003-0.0015 mg kg-1 for 20-year-old ash cores. This suggests that the older ash is enriched in toxic elements hence dust from the ash dump would be toxic to human health. The knowledge of mobility and ecotoxicological significance of coal fly ash is needed when considering its disposal or reuse in the environment. The mobility and ecotoxicology of inorganic metals in coal fly ash are determined by (i) mineralogical associations of inorganic species (ii) in-homogeneity in the ash dumps (iii) long and short term exposure to ingress CO2 and percolating rain water. Management issues such as inconsistent placement of ash in the dumps, poor choice of ash dump site, in-homogeneity in brine irrigation, no record of salt load put on the ash dumps and lack of proper monitoring requires improvement. The thesis provides justification for the use of the modified sequential extraction scheme as a predictive tool and could be employed in a similar research work. This thesis also proved that the dry ash disposal method was not environmental friendly in terms of overall leaching potential after significant chemical weathering. Moreover the study proved that the practice of brine co-disposal or irrigation on ash dumps is not sustainable as the ash dump did not act as a salt sink.

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47

Radicic, William Neil. "Velocity and Temperature Characterization of the First Vacuum Stage Expansion in an Inductively Coupled Plasma - Mass Spectrometer." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd435.pdf.

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48

Veschambre, Sophie. "Caractérisation et quantification des Eléments Traces Métalliques dans les dépôts et les particules atmosphériques de la vallée d'Aspe - Mise en place d'indicateurs de la Qualité de l'Air." Phd thesis, Université de Pau et des Pays de l'Adour, 2006. http://tel.archives-ouvertes.fr/tel-00118082.

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L'étude des apports atmosphériques des éléments traces métalliques (ETM) dans la vallée d'Aspe (Pyrénées Atlantiques) a un double objectif : (1) établir un état de référence des contaminants métalliques pour le suivi des émissions du trafic routier liés à l'ouverture du tunnel du Somport et, (2) évaluer les sources et les conditions climatologiques qui contribuent aux apports des ETM dans la vallée d'Aspe. La détermination des ETM (Al, Na, Mg, K, V, Mn, Cr, Zn, Cu, Rb, Cd, Sn, Sb, Ba, Ce, Pb et U) et des rapports isotopiques du plomb (208Pb/206Pb, 206Pb/207Pb et 208Pb/207Pb) dans les récepteurs atmosphériques (neiges fraîches, dépôts humides, particules atmosphériques et lichens) a permis de mettre en place des indicateurs de la qualité de l'air. La quantification des ETM a nécessité la mise en oeuvre de protocoles de prélèvements et d'analyses ultra-traces. Les différents récepteurs atmosphériques étudiés permettent d'intégrer une échelle temporelle journalière à pluriannuelle et un gradient spatial dans l'axe Nord-sud de la vallée et en fonction de l'altitude.
La vallée d'Aspe présente un niveau de contamination spécifique des zones éloignées des émissions anthropiques et les contaminants métalliques identifiés sont le Cd, Sb, Zn, Cu, Pb et Sn. Dans sa partie basse, les indicateurs de la qualité de l'air présentent une contribution des contaminants (i) liée aux émissions locales des combustions domestiques, à la pratique saisonnière de l'écobuage et au trafic routier, et (ii) aux sources anthropiques régionales de l'incinération des déchets ménagers, de l'industries métallurgique et des centres urbains. Dans sa partie haute, la vallée est soumise significativement, d'une part, à l'érosion éolienne et, d'autre part, à la contribution des sources du transport à grande échelle de l'hémisphère Nord. La caractérisation des ETM et des rapports isotopiques du plomb dans le tunnel du Somport indique (i) que le trafic routier émet significativement du Cu, Sb, Zn et Ba et (ii) bien que Pb présente de faibles émissions sa composition isotopique montre une source faiblement radiogénique du trafic routier. Toutefois, la faible circulation des véhicules dans la vallée d'Aspe ne permet pas de mettre évidence une contamination significative provenant des émissions du trafic routier.

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49

Black, Amanda. "Bioavailability of cadmium, copper, nickel and zinc in soils treated with biosolids and metal salts." Lincoln University, 2010. http://hdl.handle.net/10182/1561.

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It is widely accepted that bioavailability, rather than total soil concentration, is preferred when assessing the risk associated with metal contamination. Despite this, debate continues on what constitutes a bioavailable pool and how to best predict bioavailability, especially in relation to crop plants. The overall aim of this thesis was to assess and validate measures of cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) bioavailability in a range of soils amended with metal salts and biosolids. Six potential measures of bioavailability were investigated and compared: total metal; 0.04 M EDTA extraction; 0.05 M Ca(NO₃)₂ extraction; soil solution extracted using rhizon probes; effective solution concentration (CE) determined using diffusive gradients in thin films (DGT); and modelled free ion activities (WHAM 6.0). These were compared to shoot metal concentrations obtained from plants grown in three soils with contrasting properties treated with biosolids and metal salts. The first study involved a wheat seedling (Triticum aestivum) assay carried out under controlled environmental conditions on incubated soils treated with metal salts and biosolids. Results showed that the presence of biosolids resulted in increases of DOC, salinity, Ca and Mg in soil solution as well as total concentrations of Cu and Zn, dry matter was also adversely affected by increased levels of salinity. The addition of biosolids did not significantly alter the extractability or solubility of Cd, Cu, Ni and Zn although concentrations of Cd in shoots were significantly lower in plants grown in biosolids amended soils compared with unamended soils. The second study involved a field experiment that used 20 cm diameter by 30 cm deep soil monoliths of the same three soils treated with metals and biosolids, and perennial ryegrass (Lolium perenne) was grown for 24 months. Results revealed the addition of biosolids significantly increased the amount of DOC, salinity, Ca and Mg in solution. The presence of biosolids also significantly altered the bioavailability of Cd, Cu, Ni and Zn, as measured by soil solution, CE and free ion activity. However, this change had little effect on plant metal uptake. The length of time following treatment application had the greatest effect on soil chemistry and metal availability, resulting in pH decreases and increases in DOC, soil solution salinity, Ca and Mg. The free ion activities of each metal increased with time, as did soil solution Cd and Zn and CE-Cu, with results for Zn indicative of migration through the soil profile with time. Plant uptake of Ni and Zn also changed with time. Nickel concentrations in shoots decreased, while concentrations of Zn in shoots increased. The findings from the two studies demonstrated that biosolids increased the amount of DOC, salinity, Ca and Mg present in soil solution. In the lysimeter study measures of metal availability were affected in soils amended with biosolids, but this did not effect shoot concentrations. The overall predictive strengths of the six potential measures of bioavailability was investigated using results from the previously described experiments and related studies carried out by ESR and Lincoln University using nine different soils amended with combinations of biosolids and metal salts. Of the four metals Ni provided the strongest correlations between metal bioavailability and shoot concentrations, with 0.05 M Ca(NO₃)₂ extraction giving the strongest relationship for Ni concentrations in shoots (r² = 0.73). This suggests that the solubility of Ni is highly indicative of shoot concentrations and that Ca(NO₃)₂ is a robust measure of Ni bioavailability. In addition Ca(NO₃)₂ provided the best estimate of Zn bioavailability (r² = 0.65), and CE-Cd provided the best measure of Cd bioavailability, although it could only describe 47 % of shoot Cd concentration. Results for Cu were typical of previously described studies as assays of Cu availability are almost always poorly correlated with shoot concentrations, with total Cu having the strongest relationship (r² = 0.34). Methods based on the extractability and solubility of Cu in soils were poor indicators of Cu concentration in shoots. Overall, the addition of biosolids did not alter the outcome of these bioavailability assays, and results indicated that total metal concentrations present in the soils and biosolids matrix, plus length of time since soil treatment, had a greater affect on metal bioavailability.

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50

Mmelesi, Olga Kelebogile. "Synthesis and characterization of pine cone carbon supported iron oxide catalyst for dye and phenol degradation." Thesis, Vaal University of Technology, 2017. http://hdl.handle.net/10352/418.

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M. Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology
Fenton oxidation is classified into two processes, homogeneous and heterogeneous. Homogeneous Fenton oxidation process, have been shown to be efficient in the degradation of organic pollutants. However, it was shown to have limitations which can be addressed by the heterogeneous Fenton oxidation. Despite the high efficiency of the heterogeneous Fenton oxidation process in the degradation of recalcitrant organic pollutants, the currents synthesis trends of the heterogeneous Fenton catalyst have been proven to be time and energy constraining, since it involves the multi-step were the activated carbon have to be prepared first then co-precipitate the iron oxide on the activated carbon. However, as much as the heterogeneous Fenton catalyst has been proven to have high catalytic activity towards degradation of organic pollutants, these catalysts have some limitations, such limitations include metal ions being leached from the catalyst support into the treated water causing catalyst deactivation and a secondary pollution to the treated water. In this thesis, these catalysts have been applied in the degradation of recalcitrant organic pollutants such as methylene blue and phenols. This study focuses on the single step synthesis of iron oxide nanoparticles supported on activated carbon, were carbonaceous material is impregnated with iron salt then pyrolysed via microwave heating. Microwave power and the amount of iron salt were optimized. The prepared activated carbon-iron oxide composites were applied to the degradation of 2-nitrophenol (2-NP) and methylene blue (MB). Methylene blue was used as a model compound due to the fact that it is easier to monitor the degradation process with UV-Vis as compared to 2-nitrophenol . 2-nitrophenol the additional step for the adjustment of pH is required since nitrophenols are colorless in color at lower pH. The characterization showed that the microwave power and the amount of the iron precursor have an influence on the porosity and surface functional groups of the activated carbon. Further it was vi observed that microwave power and iron precursor influnces the amount of iron oxide formed on the surface of the support. It was also observed that the activated carbon-iron oxide composite have the catalytic effects on the Fenton oxidation process of MB and 2-NP. The parameters such as H2O2, pH, catalyst dose, initial concentration, temperature affect the degradation of both MB and 2-NP. Kinetics studies showed that Fenton is a surface driven reaction since the results fitted the pseudo first order model. The thermodynamics parameters also showed that the reaction is endothermic, spontaneous and is randomized. This implies that the reaction of the degradation of MB and 2-NP is feasible and the catalysts prepared have high catalytic activity. MB and 2-NP were degraded to smaller organic molecules (carboxylic acids). The stability of the catalyst observed to decrease as the number of cycles increased, this is due to the leaching of iron ions from the support material. Hence it was concluded that the activated carbon-iron oxide composite was successfully synthesized and had the high catalytic activity for the degradation of MB and 2-NP.

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