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  • 1651.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, T.
    Laboratoriet för Isotopgeologi, Naturhistoriska Riksmuseet, Stockholm.
    Hamilton, P. J.
    IIsotope Geology Unit, Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow.
    Claesson, L. Å.
    Swedish Geological Co..
    The western border of the Archaean province of the Baltic Shield: evidence from northern Sweden1987In: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967, Vol. 95, no 4, p. 437-450Article in journal (Refereed)
    Abstract [en]

    Restricted areas of acid to intermediate gneisses in northernmost Sweden are known to be Archaean and several other gneissic granodioritic to tonalitic massifs have been suggested to be of this age. To delimit the western border of the Archaean province of the Baltic Shield, and to characterize the Swedish Archaean, we have studied the 2.83 Ga old Soppero gneiss and 8 of the proposed Archaean massifs in northern Sweden by Sm-Nd isotopic analyses, U-Pb zircon dating (in two cases), and geochemistry. Of the Archaean gneisses proposed thus far, only those from the Soppero and Kukkola areas have Archaean ages (2.83 and 2.67 Ga, respectively). These gneisses have geochemical characteristics such as LREE-enrichment, low U-contents, and low K/Na-ratios, which are typical of Archaean TTG (tonalite-trondhjemite-granodiorite) rocks worldwide. The REE results indicate that the Soppero and the Kukkola gneisses were generated by partial melting of basic rocks, presumably amphibolites. According to the Sm-Nd isotopic data for the Soppero gneiss, this process occurred only a short time after initial segregation from the mantle (εNd values between +0.9 and +3.5). The Kukkola gneiss, however, has longer crustal residence time as indicated by negative εNd values (-1.0 and -2.5) at the U-Pb zircon age of 2.67 Ga. Evidence in support of an important event at that time is given by secondary overgrowth on zircon cores in the 2.83 Ga old Soppero gneiss. The Sm-Nd isotope results show that the Proterozoic granitoids in northern Sweden have a decreasing involvement of Archaean source material with increasing distance from the Archaean areas. Before the Proterozoic reworking, the rather small Archaean areas in northern Sweden presumably belonged to a large continuous Archaean craton. The western palaeoboundary of this craton in Sweden probably follows approximately a line extrapolated from the western limit of the Archaean of central Finland, passing west of Kukkola, and then continues to the Lofoten area in northern Norway.

  • 1652.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Contrasting 1.8 Ga granitoids in northern Sweden: the Edefors and Lina suites1993In: Abstracts of lectures and posters: 21:a Nordiska geologiska vintermötet 10-13 Januari 1994 Luleå / [ed] Jan-Anders Perdahl, Luleå: Högskolan i Luleå , 1993, p. 235-Conference paper (Other academic)
  • 1653.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Contrasting 1.8 Ga potassic granitoids in northern Sweden: the Edefors and Lina suites1996In: Jubilee issue: short papers and abstracts for the Jubilee meeting "Current problems, ideas and results in geology" : Stockholm 16th-18th October 1996 at the celebration of the 125th anniversary of the Geological society of Sweden / [ed] Björn Sundquist, Geologiska föreningen , 1996, p. 22-Conference paper (Other academic)
  • 1654.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Laboratory for Isotope Geology. Swedish Museum of Natural History, Stockholm.
    Diversity of 1.8 Ga potassic granitoids along the edge of the Archaean craton in northern Scandinavia: a result of melt formation at various depths and from various sources1994In: Lithos, ISSN 0024-4937, E-ISSN 1872-6143, Vol. 33, no 4, p. 265-283Article in journal (Refereed)
    Abstract [en]

    The edge of the Archaean craton in northern Scandinavia had been intensively reworked during the Svecofennian orogeny 1.93-1.86 Ga ago and was subsequently intruded by potassic granitoids of 1.79–1.80 Ga age. Despite similar or even identical ages and overlapping areas of occurrence, these rocks belong to two different groups, the Edefors and Lina granitoids, which have contrasting geochemistries and Sm---Nd isotopic characteristics. The Edefors granitoids range from syenites to granites, and are alkali-rich and distinctly metaluminous. They crystallized from dry magmas. This is indicated by the scarcity of pegmatites and aplites. The contacts to older rocks are often distinct, but gradual transitions to Lina-type granitoids are common. The Edefors granitoids have high contents of Zr but not of elements such as Y, REE, Ta and Nb, and have low Mg/Mg+Fe ratios. They also frequently have positive Eu anomalies, even in the quartz rich varieties. Initial εNd values range from −2.1 to +1.4, indicating that the Edefors granitoids were formed by the mixing of mantle-derived magmas and continental crustal materials. The amount of crustal component was probably less than 35% in most cases. The Lina granitoids are accompanied by abundant pegmatites and aplites. Ghost structures and remnants of country rock are common. True granites predominate, but also quartz monzonites occur. The content of HFS elements is low and the Mg/Mg+Fe ratios are higher than in the Edefors granitoids. Initial εNd values range from −9.3 to −3.7, reflecting a significant portion of Archaean Nd in the source materials. The Lina granitoids are largely the result of remobilisation of continental crust with a small input of juvenile material. However, the dominant source for these crustally derived granitoids are c. 1.9 Ga old granitoids. These carry a large proportion of Archaean Nd. The most probable environment of the formation of potassic migmatite granitoids, such as the Lina type, is a collision zone between two masses of felsic crust (e.g. arc-continent or continent-continent), but the details of such a collision in the Baltic Shield remain to evaluated. The formation of the Edefors granitoids could have been associated with an extensional zone developed due to delamination caused by separation of the down-dip oceanic lithosphere from the continental lithosphere.

  • 1655.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Diversity of approximately coeval 1.8 Ga granitoids in northern Sweden: a result of melt formation at various depths and from various sources1993In: Symposium on "The Svecofennian Domain": geological/geophysical aspects of the continental crust and annual meeting of IGCP-275. Abstract volume, 1993, p. 64-Conference paper (Other academic)
  • 1656.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Elming, Sten-åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The Archaean-Proterozoic boundary in northern Sweden1992In: Abstracts Volume, IGCP 275 meeting Deep Geology of the Baltic Shield: Petrozavodsk September 15-17, 1992, 1992, p. 66-67Conference paper (Other academic)
  • 1657.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Skiöld, Torbjörn
    Nisca, Dan
    Delineation and origin of the Archaean-Proterozoic boundary in northern Sweden1990In: Abstracts: Second Symposium on the Baltic Shield with Workshop on Correlation with Laurentia, Lund, Sweden June 5-7, 1990, Lund: International Geological Correlation Programme , 1990, p. 69-Conference paper (Other academic)
  • 1658.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Thunberg, Jonas
    Luleå tekniska universitet.
    Land, Magnus
    Stockholm University.
    Höglund, Lars-Olof
    Kemakta Konsult AB.
    Han, Quishang
    Luleå tekniska universitet.
    Redistribution of trace metals in a mineralized spodosol due to weathering, Liikavaara, northern Sweden2003In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 18, no 6, p. 883-899Article in journal (Refereed)
    Abstract [en]

    The till east of the Liikavaara Östra ore deposit in northern Sweden is in some parts rich in Cu and other sulphide-associated metals. Groundwater flowing in this till has higher concentrations of Cu than groundwater in a reference area where the till has low concentrations of Cu and other metals. To understand the processes that release metals from the mineralized till at Liikavaara into the groundwater, the authors performed a detailed study of the <2 mm fraction of a till profile where the highest metal concentrations in the Liikavaara area occur. The geochemistry and mineralogy of the till were determined, and the soil water was sampled by tension lysimeters. The importance of local diffusion of Cu-bearing airborne dust from the adjacent Aitik mine tailings impoundment was quantified and solid speciation of metals in airborne material was performed by sequential extraction. The results from Liikavaara were compared to results from the reference area. Glacial ice picked up sulphide-rich material from the Liikavaara Östra Cu ore during its flow. This material was deposited in the till east of the ore body when the ice melted. The sulphides have been dissolved in the <2 mm fraction during 8.7 ka of weathering since the glacial ice retreated. After dissolution of the sulphides, Cu was redistributed and secondarily retained in association with Fe-oxyhydroxides and altered biotite. Other sulphide-associated elements such as Co, Ni and Zn show the same pattern in the till profile as Cu, though the concentrations are much lower. Uptake of Cu2+ in the biotite through ion exchange with K+ may be an important mechanism for Cu-enrichment in biotite at Liikavaara. The airborne dust is not the source of Cu in the till. Although the soil water at Liikavaara has higher concentrations of Cu and other metals than the soil water at the reference area, the Cu-concentration is too low for infiltrating soil water to explain the high Cu-concentrations observed in groundwater. The high metal concentrations in the till, of Cu in particular, cause the increased concentrations in the local groundwater. A fluctuating groundwater table washes out Cu and other metals from the till. It is possible that increased Cu concentration in the local groundwater is caused by dissolved organic complexes, or by colloids (<0.45 μm) rich in organic matter and/or Fe-oxyhydroxides

  • 1659.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Proterozoic mineralizations associated with granitoids in northern Sweden: Excursion guide no 71986In: 7th IAGOD symposium and Nordkalott project meeting / [ed] Ebbe Zachrisson, Sveriges Geologiska Undersökning , 1986Conference paper (Other academic)
  • 1660.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Widerlund, Anders
    Holmström, Henning
    Ingri, Johan
    MiMi – Field studies and characterisation: state-of-the-art-report1998Report (Other academic)
  • 1661.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Aspects of the formation of the 1.80-1.77 Ga old granitoids in south-central Sweden1990In: Vol. 112, no 2, p. 189-190Article in journal (Other academic)
  • 1662.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Luleå University of Technology.
    Genesis of the Fellingsbro-type granites: evidence from gravity measurements and geochemistry1988In: Geologiska föreningens i Stockholm förhandlingar, ISSN 0016-786X, Vol. 110, no 1, p. 39-54Article in journal (Refereed)
    Abstract [en]

    The Fellingsbro granite sensu stricto is a porphyritic coarse-grained rock characterized by red angular microcline megacrysts. Samples of the Fellingsbro and the similar Lisjö granite have been analysed chemically. Both intrusions belong to a belt of ca. 1.78 Ga old granites which coincides with a major negative gravity anomaly, the so called Central Swedish Gravity Low. We have carried out gravity measurements and obtained a fairly dense regional gravity network from the Fellingsbro area to Västerås. In addition, an approx. 60km long profile with gravity stations approx. 200m apart was measured across the Lisjö granite. The porphyritic Fellingsbro and Lisjö granites were generated in a tensional environment. They rose from a huge granite ridge through structurally controlled root zones, flowed out and formed mushroom-shaped intrusions. Even-grained grained granites occurring in the Fellingsbro and Lisjö areas were generated through a mixing between the original granitic magma and locally remobilized country rocks. The porphyritic granites are of the same age and have similar geochemical and geophysical properties as the Småland-Värmland granites. Both groups were probably generated in a tensional environment on the continental side of a major subduction-related calc-alkaline belt; remnants of which may be preserved in the Southwest Swedish Gneiss region. The Lisjö and Fellingsbro granites were generated more towards the interior of the pre-existing ca 1.9 Ga old continent.

  • 1663.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zuber, Josef
    Luleå University of Technology.
    Geochemistry of the fellingsbro type granites, south central Sweden1988In: Geologie & Mijnbouw, ISSN 0016-7746, E-ISSN 1573-9708, Vol. 67, no 2-4, p. 213-225Article in journal (Refereed)
    Abstract [en]

    The Fellingsbro granite sensu stricto is a massive coarse-grained rock characterized by red, angular microcline megacrysts up to 7 cm long. The Lisjo granite is of the same type as the Fellingsbro granite but is situated 20 km to the NE. Gravity studies suggest that the Fellingsbro and Lisjo granites rose from a huge granite ridge through structuraly controlled root zones, forming mushroom-shaped intrusions. These porphyritic granites have the geochemical characteristics (eg high Y, Nb, Zr and HREE) of granites generated as "within-plate' or tensional rifting environments. The even-grained interior of the Lisjo granite and the contemporaneous Dingtuna and Pingstaberg granites, were generated by differentiation of granites with similar characteristics as the porphyritic Fellingsbro granite. Recently published U-Pb zircon datings have demonstrated that the Smaland-Varmland granite-porphyry Belt has approximately the same age as the granites in this study. We speculate that both groups were emplaced in a tensional environment on the continental side of a subduction related calc-alkaline belt, remnants of which may be preserved in the SW Swedish Gneiss Region.

  • 1664.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Applications of the DGT technique for measurements of anions and cations in natural waters2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since the toxicity and mobility of trace metals are related to the metals' speciation, robust methods for trace metal speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique.In this work the commercially available DGT containing ferrihydrite adsorbent, used for determination of phosphate and inorganic arsenic, was characterised with respect to anionic molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed.The combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT was used for speciation of copper and nickel at three brackish water stations with different salinities in the Baltic Sea. Time series and depth profiles were taken, and complementary membrane- (<0.22 μm) and ultrafiltration (<1 kDa) was conducted. Comparing DGT and ultrafiltration measurements indicated that copper and nickel were complexed. Due to small differences in results between the OP and RP DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in that both DGTs accumulating essentially the same fraction. Further, there seemed to be a trend in copper speciation indicating higher degree of strong complexation with increasing salinity. The low salinity stations are more affected by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend.

  • 1665.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Further characterisation and applications of the diffusive gradients in thin films technique: In situ measurements of anions and cations in environmental waters2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As both the toxicity and the mobility of trace elements are related to chemical forms present, robust methods for element speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique. The aim of this thesis was to explore new application areas as well as carry out further characterisation of DGT-adsorbents already on the market. The commercially available DGT containing ferrihydrite adsorbent, currently in use for the determination of phosphate and inorganic arsenic, was characterised with respect to anionic arsenate, molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed. Further investigations of the ferrihydrite-DGT device were done with respect to organic arsenic species. From previous research it is understood that the two most prevalent forms of organic arsenic in natural waters, monomethylarsinate (MMA) and dimethylarsonate (DMA), adsorb to ferrihydrite. It was concluded that MMA and under some conditions DMA are accumulated and might therefore be included in total arsenic measurements. A method for speciation of inorganic As, DMA and MMA was described. DGT sampling was applied at three stations, with different salinities, in the brackish Baltic Sea. Time series as well as vertical profiles were taken and complementary membrane- (<0.22 μm) and ultrafiltrations (<1 kDa) were conducted on discrete samples collected at 5 m depth. A combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT, both loaded with Chelex cation exchanger, was used for speciation of copper and nickel. Due to minimal differences in results between the OP- and RP-DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in both DGTs accumulating essentially the same fraction. Furthermore, there seemed to be a trend in copper speciation indicating a higher degree of strong complexation with increasing salinity. The low salinity stations are more impacted by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend. Additionally, uranium results from the same sampling tours were used to evaluate OP-DGT for in situ uranium measurements. Previous research has focused on laboratory studies for characterisation of a range of suitable uranium adsorbents, including Chelex. From the Baltic Sea study, a strong correlation between DGT-labile uranium and pH was revealed. The correlation could not be associated to organic complexation, since the ultrafiltration results implicated that uranium was truly dissolved. Instead it must be attributed to the formation of stable inorganic anionic uranyl-carbonate complexes, the stability of which increases with increasing numbers of carbonates and pH. Transplanted aquatic moss has commonly been used to monitor bioavailable trace metal contaminations in freshwater. Like the DGT technique the method has the advantage of generating time-weighted averaged concentrations. The DGT technique has in several previous studies been suggested to mimic biological uptake of trace metals. Four speciation/fractionation techniques – DGT, transplanted aquatic moss, ultrafiltration (1 kDa) and membrane filtration (0.22 μm) – were used in parallel for measurements of Al, Cd, Co, Cu, Fe, Mn, Ni and Zn in a contaminated freshwater stream in northern Sweden. Differences and similarities between the methods were investigated and how these depend on geochemical water quality. Strong correlations between DGT-results and the concentrations in the filtrate (<0.22 μm) and ultrafiltration permeate for Al, Cu, Cd, Co and Zn were detected and, generally, elevated trace metal concentrations were found in the transplanted moss, compared to moss from the non-polluted reference stream. However, no correlation between moss and DGT-labile concentrations could be discerned.

  • 1666. Österlund, Helene
    et al.
    Chlot, Sara
    Faarinen, Mikko
    ALS Laboratory Group, Luleå.
    Widerlund, Anders
    Rodushkin, Ilya
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Simultaneous measurements of As, Mo, Sb, V and W using a ferrihydrite diffusive gradients in thin films (DGT) device2010In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 682, no 1-2, p. 59-65Article in journal (Refereed)
    Abstract [en]

    The ferrihydrite-backed DGT (diffusive gradients in thin films), recently developed for arsenic and phosphate measurements was, for the first time, characterized with respect to molybdate, antimonate, vanadate and tungstate determination. Arsenate was included in the characterization to allow comparison with literature data and thus provide quality control of the measurements. In addition to laboratory experiments, field measurements were carried out in a natural stream in northern Sweden affected by mine drainage. It was shown that ferrihydrite-DGT is suitable for simultaneous determination of labile arsenic, molybdate, antimonate, vanadate and tungstate over a wide pH range. Diffusion coefficients were estimated using two different methods; diffusion cell and direct uptake to DGT devices in synthetic solutions. Estimations of the coefficients using the direct uptake method were performed between pH 4 and 8. The results from the two methods agreed well irrespective of pH, except for molybdate and antimonate that showed decreased values at pH 8. Adsorption of the analytes to ferrihydrite gel discs was rapid at all pH values. However, there was a tendency toward lower adsorption affinity for antimonate compared to the other anions. 100% recovery of accumulated analytes was achieved through complete dissolution of the ferrihydrite adsorbent using 1.4 mol L-1 HNO3 with 0.1 mol L-1 HF. From field sampling it was concluded that the opportunities for accurate antimonate and molybdate determination decrease at pH ≥8.7. DGT labile concentrations were generally lower than dissolved concentrations. Relatively lower DGT concentrations, compared to dissolved (<0.45 μm), were observed under a period when ferric oxide precipitations were detected on the DGT protective filter.

  • 1667.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Faarinen, Mikko
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Contribution of organic arsenic species to total arsenic measurements using ferrihydrite-backed diffusive gradients in thin films (DGT)2012In: Environmental Chemistry, ISSN 1448-2517, E-ISSN 1449-8979, Vol. 9, no 1, p. 55-62Article in journal (Refereed)
    Abstract [en]

    In previous publications discussing arsenic determination using ferrihydrite-backed diffusive gradients in thin films (DGT) devices, organic arsenic forms have been disregarded, even though it is known that the two most prevalent in natural waters, dimethylarsinate (DMA) and monomethylarsonate (MMA), may adsorb to ferrihydrite and thereby be included in the measurement. In this work the accumulation of DMA and MMA, as well as inorganic arsenite and arsenate, to ferrihydrite-backed DGT devices was investigated. It could be demonstrated that MMA, and under acidic conditions also DMA, adsorbed to the binding layer and might therefore contribute to the total mass of measured arsenic. Diffusion coefficients were measured for all four species to enable quantification of DGT-labile concentrations of organic and inorganic arsenic. Elution of the analytes from the ferrihydrite binding layer was performed using 1 mL of 1 M NaOH to facilitate arsenic speciation analysis using chromatographic separation. Average recovery rates were between 87 and 108%. This study shows that the contribution of DMA and MMA to the total accumulated mass must be taken into consideration when evaluating DGT data in future studies.

  • 1668.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Gelting, Johan
    Nordblad, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    ALS Scandinavia AB.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Copper and nickel in ultrafiltered brackish water: labile or non-labile?2012In: Marine Chemistry, ISSN 0304-4203, E-ISSN 1872-7581, Vol. 132-133, no 1, p. 34-43Article in journal (Refereed)
    Abstract [en]

    Copper and nickel were sampled at three stations in the Baltic Sea using diffusive gradients in thin films (DGT) passive samplers and ultrafiltration (< 1 kDa). Two versions of DGT devices were used, the normal open pore (OP) and a restricted pore (RP). The OP DGT and RP DGT concentrations closely followed each other both in depth profiles and time series. The lack of significant difference between OP and RP DGT suggests that the labile complexes were smaller than the pore size of the RP gel (approximately 1 nm). These data, together with OP DGT measurements at the same location in two different years, clearly demonstrate that the DGT method is robust and indicates reproducible results during routine field conditions.Between 50 and 80% of the ultrafiltered fractions for Ni and Cu could not be detected by the DGT method, using standard procedures. This suggests the presence of complexing ligands for Cu and Ni. Assuming 100% complexation of Ni to fulvic acid ligand gave DGT concentrations similar to ultrafiltered Ni concentrations. The equivalent calculation for Cu indicates that up to 75% of the ultrafiltered Cu fraction is non-labile. The non-labile Cu complexes are proposed to be produced at sea since the fraction increases with decreasing terrestrial influence.

  • 1669.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ylinenjärvi, Karin
    ALS Scandinavia AB.
    Baxter, Douglas
    Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry2009In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 29, no 4, p. 1258-1264Article in journal (Refereed)
    Abstract [en]

    A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na2CO3 and ZnO and placed in an oven at 560 °C for 1 h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200 mg/kg for chlorine and 20 mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

  • 1670.
    Frietsch, Rudyard (Editor)
    Luleå tekniska universitet.
    Register över svenska fyndigheter av malmmineral och industriella mineral och bergarter1991Report (Other academic)
  • 1671.
    Stegmann, Bo
    Egen konsultfirma.
    Vittring i skogsmark i Gävleborg1992Report (Other academic)
    Abstract [sv]

    Underlagsmaterial

    Underlaget till kartorna och vittringsberäkningarna i denna rapport är ett omfattande analysmaterial från länsstyrelsen och Terra Minings kartering av Gävleborgs län, bestående av 4109 prover tagna i moränmark från hela länet och ståndortskarteringens material från 128 provpunkter i skogsmark. Länsstyrelsens och Terra Minings analysresultat indelades i tre geokemiklasser för Ca, K resp. Mg. Denna indelning utgjorde underlag för indelning av moränmarken i geokemiområden.

    Ståndortskateringens analysresultat användes till vittringsberäkningar för dessa avgränsade geokemiområden.

    Vittringsberäkning

    Vittringsberäkning utfördes för varje avgränsat geokemiområde med hjälp av en vittringsfunktion innehållande temperatur, latitud och elementhalt. Ett max- och minvärde beräknades för resp, geokemiklass.

    En jämförelse gjordes med en vittringsstudie över skogsmark för hela Sverige, där samma vittringsfunktion användes som i denna rapport. Den framräknade K- och Mg- vittringen i studien över hela Sverige. K-vittringen i denna rapport var mindre än motsvarande vittring i studien för hela Sverige. Resultatet från vittringsberäkningarna jämfördes med en catchment studie i mellersta Hälsingland där framräknad vittring av K och Mg sammanföll med denna rapports värden. Ca- vittringen var drygt dubbelt så hög som värdet för denna rapport. Ca- vittringsberäkningarna i denna rapport jämfördes också med en Sr-isotop studie från samma område i mellersta Hälsingland. Ca- vittringen i denna rapport var 60-70% av Ca- vittringen i Sr- isotop studien. En med matematisk simulering framräknad sammanlagd vittring av Na, Mg, Ca och K jämfördes med denna rapports sammanlagda vittring av Mg, Ca och k och en framräknad vittring av Na. Vittringsvärdena sammanföll väl mellan de två studierna.

    Kartor

    Sammanlagt tretton kartor togs fram över Gävleborgs län. En höjdkarta med 100 meters intervall, en texturkarta (jordartskarta) med fyra texturklasser, tre berggrundskartor utvisande Mg-, Ca-och K-rik respektive fattig berggrund, tre geokemikartor över Ca, K och Mg, vardera indelad i tre geokemiklasser, två kombinerade textur och geokemikartor över Ca och Mg med vardera tre texturer och tre geokemiklasser samt tre vittringskartor över Mg, Ca och K med vardera fem vittringsklasser.

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