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G Kostakis - One of the best experts on this subject based on the ideXlab platform.
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characterization of the fly ashes from the lignite burning power plants of northern greece based on their quantitative Mineralogical Composition
Journal of Hazardous Materials, 2009Co-Authors: G KostakisAbstract:In the present work, Mineralogical analysis of fly ashes produced from the brown coal burning power plants of Agios Dimitrios, Kardia, Ptolemais, LIPTOL, Amynteon, and Achlada-Meliti (Western Macedonia, Greece) was performed, with the aim of characterizing the ashes on the basis of their quantitative mineral phase Composition and asses their variability at different time periods. The fly ashes from the Agios Dimitrios, Kardia, and Ptolemais power plants were found to have nearly the same Mineralogical Composition, consisting mainly of feldspars, lime, anhydrite, quartz, calcium silicates, and high amounts of amorphous phases. The fly ashes from Amynteon were slightly different, having lower content of lime and higher content of feldspars, whilst those from LIPTOL had a relative variable quantitative Composition. The fly ashes from the Meliti-Achlada power plant consisted mainly of amorphous phases (very high amounts), mullite, feldspars, and quartz. The Mineralogical Composition of the ashes produced in all the power plants, except from these of LIPTOL, did not fluctuate significantly over time. An assessment of the hydraulic (cementitious) or pozzolanic character of the ashes is proposed, introducing the use of triangle diagrams A-B-C, which represent the total fraction of the phases with hydraulic or pozzolanic (A), inert (B) character, and the amorphous phases (C).
Marc R Bustin - One of the best experts on this subject based on the ideXlab platform.
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a multidisciplinary approach in determining the maceral kerogen type and Mineralogical Composition of upper cretaceous eagle ford formation impact on pore development and pore size distribution
International Journal of Coal Geology, 2017Co-Authors: Gareth R L Chalmers, Marc R BustinAbstract:Abstract Maceral (kerogen or organic matter type) and Mineralogical Composition with the associated porosity of the Upper Cretaceous Eagle Ford Formation, Karnes County, Texas was investigated. In Karnes County, the calcareous mudstone of the Eagle Ford Formation was deposited in an open marine outer shelf to upper slope environment. To adequately characterise all components of this mudrock, a multidisciplinary approach was implemented to analyse 26 core samples from a single producing well that completed within the Eagle Ford Formation. Analyses included organic petrology, organic geochemistry, light and electron microscopy (and spectroscopy), pore size distribution analyses and X-ray diffraction. The bitumen reflectance ranges between 1.94 and 2.08% (calculated VR o = 1.60–1.69%) indicating the mudrock is in the condensate-rich gas window. The TOC content ranges between 1.7% and 7.2% with an average of 3.9%. Mineral Composition is dominated in descending order by calcite, clay, quartz and plagioclase. Calcite varies between 32% and 87% with an average of 57%. Porosity measured by helium pycnometry ranges between 3.5 and 10.3% with an average of 7.5%. Organic petrology coupled with backscattered and field emission scanning electron microscopy indicates matrix bitumen as the most significant contributor to the TOC content and porosity. Matrix bitumen contains significant meso- and microporosity and is enhanced by the secondary cracking of the bitumen. An increase in bioclastic (mostly foraminifera) and siliciclastic components correlates with lower TOC content due to the lower volume of organic-rich matrix. Peloids (fecal pellets) are calcareous, organic rich and lack terrigenous sediment indicating a zooplankton source. Pelagic deposition of peloids is interpreted as a primary mechanism of amorphinite deposition which is converted to hydrocarbons and matrix bitumen. The mixed siliciclastic calcareous matrix that surrounds the peloids is comprised of matrix bitumen and dispersed organics from land plants (vitrinite, fusinite and inertodetrinite). The siliciclastic component increases in the middle of the Eagle Ford and marks the boundary (maximum flooding surface) between the lower (TST) and upper (HST) section of the formation. The inorganic and organic components suggest a mixed terrigenous and marine source with both inorganic and organic sediments being derived from the proximal Ouachita thrust belt and from pelagic organisms within the overlying water column. The lower (TST) Eagle Ford Formation contains more micro- and mesopores than the upper (HST) Eagle Ford Formation due to higher TOC content in the lower Eagle Formation. These results illustrate that a multidisciplinary approach is necessary to identify how pore network are distributed within mudrocks and how this distribution is controlled by organic/inorganic deposition and hydrocarbon generation processes.
Emilie Journet - One of the best experts on this subject based on the ideXlab platform.
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quantitative study of the Mineralogical Composition of mineral dust aerosols by x ray diffraction
Talanta, 2018Co-Authors: Sophie Nowak, Sandra Lafon, Sandrine Caquineau, Emilie Journet, Benoit LaurentAbstract:Mineral dust aerosols, produced by wind erosion in arid regions and semi-arid surfaces, are important components of the atmosphere that affect the Earth radiative budget, atmospheric chemistry and biogeochemical cycles. Dust aerosol particles are composed of a complex mixture of various minerals, mainly clays, calcite, quartz, feldspars and iron oxides. The nature and the relative abundance of the minerals are key parameters to evaluate mineral dust environmental impacts. Strong limitations remain to quantify the Mineralogical Composition of dust particles, mainly due to the low mass of in-situ collected dust particle samples. In this study, an analytical method and X-Ray Diffraction (XRD) measurements are presented to quantify the Mineralogical Composition of low mass aerosol particle samples. The method is applied on reference minerals (illite, kaolinite and palygorskite) commonly present in desert dust aerosols, as well as on lab-generated dust aerosols from desert soils. XRD measurements of theses samples in rotation in a glass capillary are combined with the Rietveld refinement method. The results obtained are repeatable and confronted to theoretical values given in the literature for the reference minerals. This method allows us to quantify the Mineralogical Composition of low mass dust mineral samples with an unprecedented accuracy.
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mapping the physico chemical properties of mineral dust in western africa Mineralogical Composition
Atmospheric Chemistry and Physics, 2014Co-Authors: Paola Formenti, Sandrine Caquineau, Emilie Journet, Karine Desboeufs, Anne Klaver, Servanne Chevaillier, Jeanlouis RajotAbstract:Abstract. In the last few years, several ground-based and airborne field campaigns have allowed the exploration of the properties and impacts of mineral dust in western Africa, one of the major emission and transport areas worldwide. In this paper, we explore the synthesis of these observations to provide a large-scale quantitative view of the Mineralogical Composition and its variability according to source region and time after transport. This work reveals that mineral dust in western Africa is a mixture of clays, quartz, iron and titanium oxides, representing at least 92% of the dust mass. Calcite ranged between 0.3 and 8.4% of the dust mass, depending on the origin. Our data do not show a systematic dependence of the dust Mineralogical Composition on origin; this is to be the case as, in most of the instances, the data represent the Composition of the atmospheric burden after 1–2 days after emission, when air masses mix and give rise to a more uniform dust load. This has implications for the representation of the mineral dust Composition in regional and global circulation models and in satellite retrievals. Iron oxides account for 58 ± 7% of the mass of elemental Fe and for between 2 and 5% of the dust mass. Most of them are composed of goethite, representing between 52 and 78% of the iron oxide mass. We estimate that titanium oxides account for 1–2% of the dust mass, depending on whether the dust is of Saharan or Sahelian origin. The Mineralogical Composition is a critical parameter for estimating the radiative and biogeochemical impact of mineral dust. The results regarding dust Composition have been used to estimate the optical properties as well as the iron fractional solubility of Saharan and Sahelian dust. Data presented in this paper are provided in numerical form upon email request while they are being turned into a public database, the Dust-Mapped Archived Properties (DUST-MAP), which is an open repository for Compositional data from other source regions in Africa and worldwide.
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mineralogy as a critical factor of dust iron solubility
Geophysical Research Letters, 2008Co-Authors: Emilie Journet, Sandrine Caquineau, Karine Desboeufs, J L ColinAbstract:[1] To understand the impact of dust deposition on ocean primary productivity, the evaluation of dust input is not sufficient, and the soluble iron supply is also needed. Measurements of iron in aerosols suggest a much higher solubility than in soil, implying substantial atmospheric processing of chemical or physical nature. Here, we have investigated the effect of the mineralogy on iron solubility. We have measured iron solubility from some minerals commonly found in dust (clay, feldspar and iron (hydr-)oxides). Firstly, we observe a greater solubility of iron resulting from clays (~4%) in comparison to iron (hydr-)oxides (<1%), independently of specific surface of minerals. Secondly, by considering amount of dissolved iron and the Mineralogical Composition of dust, our results indicate that dissolved iron fraction mainly comes from clay dissolution in contrast to that assumed in some biogeochemical models. In consequence, it appears that iron solubility is closely linked to the Mineralogical Composition of aerosol.
Sandrine Caquineau - One of the best experts on this subject based on the ideXlab platform.
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quantitative study of the Mineralogical Composition of mineral dust aerosols by x ray diffraction
Talanta, 2018Co-Authors: Sophie Nowak, Sandra Lafon, Sandrine Caquineau, Emilie Journet, Benoit LaurentAbstract:Mineral dust aerosols, produced by wind erosion in arid regions and semi-arid surfaces, are important components of the atmosphere that affect the Earth radiative budget, atmospheric chemistry and biogeochemical cycles. Dust aerosol particles are composed of a complex mixture of various minerals, mainly clays, calcite, quartz, feldspars and iron oxides. The nature and the relative abundance of the minerals are key parameters to evaluate mineral dust environmental impacts. Strong limitations remain to quantify the Mineralogical Composition of dust particles, mainly due to the low mass of in-situ collected dust particle samples. In this study, an analytical method and X-Ray Diffraction (XRD) measurements are presented to quantify the Mineralogical Composition of low mass aerosol particle samples. The method is applied on reference minerals (illite, kaolinite and palygorskite) commonly present in desert dust aerosols, as well as on lab-generated dust aerosols from desert soils. XRD measurements of theses samples in rotation in a glass capillary are combined with the Rietveld refinement method. The results obtained are repeatable and confronted to theoretical values given in the literature for the reference minerals. This method allows us to quantify the Mineralogical Composition of low mass dust mineral samples with an unprecedented accuracy.
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mapping the physico chemical properties of mineral dust in western africa Mineralogical Composition
Atmospheric Chemistry and Physics, 2014Co-Authors: Paola Formenti, Sandrine Caquineau, Emilie Journet, Karine Desboeufs, Anne Klaver, Servanne Chevaillier, Jeanlouis RajotAbstract:Abstract. In the last few years, several ground-based and airborne field campaigns have allowed the exploration of the properties and impacts of mineral dust in western Africa, one of the major emission and transport areas worldwide. In this paper, we explore the synthesis of these observations to provide a large-scale quantitative view of the Mineralogical Composition and its variability according to source region and time after transport. This work reveals that mineral dust in western Africa is a mixture of clays, quartz, iron and titanium oxides, representing at least 92% of the dust mass. Calcite ranged between 0.3 and 8.4% of the dust mass, depending on the origin. Our data do not show a systematic dependence of the dust Mineralogical Composition on origin; this is to be the case as, in most of the instances, the data represent the Composition of the atmospheric burden after 1–2 days after emission, when air masses mix and give rise to a more uniform dust load. This has implications for the representation of the mineral dust Composition in regional and global circulation models and in satellite retrievals. Iron oxides account for 58 ± 7% of the mass of elemental Fe and for between 2 and 5% of the dust mass. Most of them are composed of goethite, representing between 52 and 78% of the iron oxide mass. We estimate that titanium oxides account for 1–2% of the dust mass, depending on whether the dust is of Saharan or Sahelian origin. The Mineralogical Composition is a critical parameter for estimating the radiative and biogeochemical impact of mineral dust. The results regarding dust Composition have been used to estimate the optical properties as well as the iron fractional solubility of Saharan and Sahelian dust. Data presented in this paper are provided in numerical form upon email request while they are being turned into a public database, the Dust-Mapped Archived Properties (DUST-MAP), which is an open repository for Compositional data from other source regions in Africa and worldwide.
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mineralogy as a critical factor of dust iron solubility
Geophysical Research Letters, 2008Co-Authors: Emilie Journet, Sandrine Caquineau, Karine Desboeufs, J L ColinAbstract:[1] To understand the impact of dust deposition on ocean primary productivity, the evaluation of dust input is not sufficient, and the soluble iron supply is also needed. Measurements of iron in aerosols suggest a much higher solubility than in soil, implying substantial atmospheric processing of chemical or physical nature. Here, we have investigated the effect of the mineralogy on iron solubility. We have measured iron solubility from some minerals commonly found in dust (clay, feldspar and iron (hydr-)oxides). Firstly, we observe a greater solubility of iron resulting from clays (~4%) in comparison to iron (hydr-)oxides (<1%), independently of specific surface of minerals. Secondly, by considering amount of dissolved iron and the Mineralogical Composition of dust, our results indicate that dissolved iron fraction mainly comes from clay dissolution in contrast to that assumed in some biogeochemical models. In consequence, it appears that iron solubility is closely linked to the Mineralogical Composition of aerosol.
Jeanlouis Rajot - One of the best experts on this subject based on the ideXlab platform.
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mapping the physico chemical properties of mineral dust in western africa Mineralogical Composition
Atmospheric Chemistry and Physics, 2014Co-Authors: Paola Formenti, Sandrine Caquineau, Emilie Journet, Karine Desboeufs, Anne Klaver, Servanne Chevaillier, Jeanlouis RajotAbstract:Abstract. In the last few years, several ground-based and airborne field campaigns have allowed the exploration of the properties and impacts of mineral dust in western Africa, one of the major emission and transport areas worldwide. In this paper, we explore the synthesis of these observations to provide a large-scale quantitative view of the Mineralogical Composition and its variability according to source region and time after transport. This work reveals that mineral dust in western Africa is a mixture of clays, quartz, iron and titanium oxides, representing at least 92% of the dust mass. Calcite ranged between 0.3 and 8.4% of the dust mass, depending on the origin. Our data do not show a systematic dependence of the dust Mineralogical Composition on origin; this is to be the case as, in most of the instances, the data represent the Composition of the atmospheric burden after 1–2 days after emission, when air masses mix and give rise to a more uniform dust load. This has implications for the representation of the mineral dust Composition in regional and global circulation models and in satellite retrievals. Iron oxides account for 58 ± 7% of the mass of elemental Fe and for between 2 and 5% of the dust mass. Most of them are composed of goethite, representing between 52 and 78% of the iron oxide mass. We estimate that titanium oxides account for 1–2% of the dust mass, depending on whether the dust is of Saharan or Sahelian origin. The Mineralogical Composition is a critical parameter for estimating the radiative and biogeochemical impact of mineral dust. The results regarding dust Composition have been used to estimate the optical properties as well as the iron fractional solubility of Saharan and Sahelian dust. Data presented in this paper are provided in numerical form upon email request while they are being turned into a public database, the Dust-Mapped Archived Properties (DUST-MAP), which is an open repository for Compositional data from other source regions in Africa and worldwide.