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Graciela Ponce-Antón, Anna Arizzi, Maria Cruz Zuluaga, Giuseppe Cultrone, Luis Angel Ortega, Juantxo Agirre Mauleon
Archaeological lime mortars from the Tower Keep and West perimeter wall of Irulegi Castle (Navarre, Spain) were analysed to determine susceptibility to deterioration. Chemical, mineralogical, textural and physical characterisation was performed by different tests and multianalysis techniques in order to determine the intrinsic features of the original historical mortars at the castle. Samples from the Tower Keep are more prone to deteriorate compared with the West perimeter wall due to high water absorption capacity and high porosity...
February 15, 2019: Materials
E Photos-Jones, C W Knapp, D Venieri, G E Christidis, C Elgy, E Valsami-Jones, I Gounaki, N C Andriopoulou
This paper introduces a holistic approach to the study of Greco-Roman (G-R) lithotherapeutics. These are the minerals or mineral combinations that appear in the medical and scientific literature of the G-R world. It argues that they can best be described not simply in terms of their bulk chemistry/mineralogy but also their ecological microbiology and nanofraction component. It suggests that each individual attribute may have underpinned the bioactivity of the lithotherapeutic as an antibacterial, antifungal or other...
December 2018: Journal of Archaeological Science, Reports
Eshani Hettiarachchi, Shaylene Paul, Daniel Cadol, Bonnie Frey, Gayan Rubasinghege
The recent increase in cardiovascular and metabolic disease in the Navajo population residing close to the Grants Mining District (GMD) in New Mexico is suggested to be due to exposure to environmental contaminants, in particular uranium in respirable dusts. However, the chemistry of uranium-containing-dust dissolution in lung fluids and the role of mineralogy are poorly understood, as is their impact on toxic effects. The current study is focused on the dissolution of xcontaining-dust, collected from several sites near Jackpile and St...
February 12, 2019: Environmental Science & Technology Letters
Anshuman Bhardwaj, Lydia Sam, F Javier Martín-Torres, María-Paz Zorzano
Several interpretations of recurring slope lineae (RSL) have related RSL to the potential presence of transient liquid water on Mars. Such probable signs of liquid water have implications for Mars exploration in terms of rover safety, planetary protection during rover operations, and the current habitability of the planet. Mawrth Vallis has always been a prime target to be considered for Mars rover missions due to its rich mineralogy. Most recently, Mawrth Vallis was one of the two final candidates selected by the European Space Agency as a landing site for the ExoMars 2020 mission...
February 14, 2019: Scientific Reports
Ricardo Ulloa, Ana Moya-Beltrán, Camila Rojas-Villalobos, Harold Nuñez, Patricia Chiacchiarini, Edgardo Donati, Alejandra Giaveno, Raquel Quatrini
Extreme acidophiles play central roles in the geochemical cycling of diverse elements in low pH environments. This has been harnessed in biotechnologies such as biomining, where microorganisms facilitate the recovery of economically important metals such as gold. By generating both extreme acidity and a chemical oxidant (ferric iron) many species of prokaryotes that thrive in low pH environments not only catalyze mineral dissolution but also trigger both community and individual level adaptive changes. These changes vary in extent and direction depending on the ore mineralogy, water availability and local climate...
2019: Frontiers in Microbiology
Meret Aeppli, Ralf Kaegi, Ruben Kretzschmar, Andreas Voegelin, Thomas B Hofstetter, Michael Sander
Electron transfer to ferric iron in (oxyhydr-)oxides (hereafter iron oxides) is a critical step in many processes that are central to the biogeochemical cycling of elements and to contaminant dynamics. Understanding these processes requires analytical approaches that allow for characterizing the reactivity of iron oxides towards reduction under thermodynamically controlled conditions. Here, we used mediated electrochemical reduction (MER) to follow changes in iron oxide reduction extents and rates during abiotic ferrous iron-induced transformation of six-line ferrihydrite...
February 13, 2019: Environmental Science & Technology
Charlotte A Abney Salomon
This article examines the role of the blowpipe in the discovery process of the disproportionately large number of new elements found by Swedish chem-ists during the eighteenth century and into the nineteenth. While individual chemists abroad used versions of the tool, in Sweden alone its use was ubiquitous across the chemical and mineralogical research community, and its consistently simple handheld design made basic dry chemical analysis quick, cheap, and portable. This shared use of the tool was crucial to the development of the mineral analysis projects that uncovered new substances, first by enabling the adoption of a system defining minerals by their chemical components and mineralogy by chemical analysis, and second by providing a simple and practical method for that analysis that facilitated collaboration across institutions, physical distance, and time...
February 5, 2019: Ambix
Cherie L DeVore, Lucia Rodriguez-Freire, Abdul Mehdi-Ali, Carlyle Ducheneaux, Kateryna Artyushkova, Zhe Zhou, Drew E Latta, Virgil W Lueth, Melissa Gonzales, Johnnye Lewis, José M Cerrato
The mobilization of arsenic (As) from riverbank sediments affected by the gold mining legacy in north-central South Dakota was examined using aqueous speciation chemistry, spectroscopy, and diffraction analyses. Gold mining resulted in the discharge of approximately 109 metric tons of mine waste into Whitewood Creek (WW) near the Homestake Mine and Cheyenne River at Deal Ranch (DR), 241 km downstream. The highest concentrations of acid-extractable As measured from solid samples was 2020 mg kg-1 at WW and 385 mg kg-1 at DR...
February 4, 2019: Environmental Science. Processes & Impacts
Segun A Akinyemi, Wilson M Gitari, Leslie F Petrik, Bemgba B Nyakuma, James C Hower, Colin R Ward, Marcos L S Oliveira, Luis F O Silva
Coal combustion and the disposal of combustion wastes emit enormous quantities of nano-sized particles that pose significant health concerns on exposure, particularly in unindustrialized countries. Samples of fresh and weathered class F fly ash were analysed through various techniques including X-ray fluorescence (XRF), X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), field-emission gun scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM) coupled with energy dispersive x-ray spectroscopy (EDS), and Raman Spectroscopy...
January 25, 2019: Science of the Total Environment
E Loginova, M Proskurnin, H J H Brouwers
The challenge of sustainable use of MSWI residues such as fly ash is particularly acute. One of the possible uses of these residues in making secondary building materials. However, MSWI fly ash is highly contaminated with toxic elements such as Pb, Zn, Cd, Cu, etc. Its treatment to reduce the environmental impact is required before reuse or disposal. Here, the efficiency of a new three-step combined treatment with two complexing agents (ethylenediaminetetraacetate and gluconate) to increase the toxic-element elution from fly ash in contrast to conventional water-only treatments is shown...
January 30, 2019: Journal of Environmental Management
Dan Stumbea, Marius Marian Chicoș, Valentin Nica
The study tailing pond shows a particular geometry resulting from the tailings stockpiles deposited onto the northern part of the beach. This generated three types of superficial waste: (i) tailings of the stockpiles (A-type) (pH=2.2-2.6; soluble fraction average - SF=14.2%), subjected to intense oxidation and evaporation; (ii) tailings of the lowlands of waste, characterized by low oxidation and no evaporation (B-type) (pH=2.7-3.1; SF=7.7%); (iii) salt crusts (C-type) (pH=2.6-3.5; SF=81.5%), formed by the evaporation of leachates accumulated in stagnant pools...
January 23, 2019: Journal of Hazardous Materials
Shelby Rader, Raina M Maier, Mark Barton, Frank Mazdab
This study shows thallium (Tl) concentrations in Brassica juncea (Indian mustard) tissue are over an order of magnitude higher (3830 μg/kg) than the substrate (100 μg/kg) and are strongly influenced by the underlying mineralogy, i.e., Tl bioaccessibility depends on the mineral structure: K-feldspar > Mn-nodule > hendricksite mica. The majority of Tl for all substrates is contained in edible parts of the plant, i.e. leaves (41% of total Tl, on average) ≥ flower stems (34%) > seed pods (11%) ≈ stems (10%) > flowers (3%)...
February 1, 2019: Environmental Science & Technology
Mafalda Costa, Ana Margarida Arruda, Rui Barbosa, Pedro Barrulas, Peter Vandenabeele, José Mirão
Five scarabs and one scaraboid found in Vinha das Caliças 4 (Beja, Portugal) were analyzed using a micro-analytical methodology in order to determine their mineralogical and chemical composition. Microstructural characterization and chemical analysis revealed that all were composed of a white body of crushed feldspathic sand covered by a lead-rich, alkaline-depleted silicate blue-green glaze showing evident signs of glass deterioration. Variable pressure scanning electron microscopy with X-ray energy dispersive spectrometry, handheld X-ray fluorescence spectroscopy, and micro X-ray diffraction results show that blue-green color of the glaze was produced by using copper ions (Cu2+) in conjunction with the lead antimonate bindheimite, a yellow-colored opacifier...
January 31, 2019: Microscopy and Microanalysis
T M DeCarlo, S Comeau, C E Cornwall, L Gajdzik, P Guagliardo, A Sadekov, E C Thillainath, J Trotter, M T McCulloch
Ocean acidification poses a serious threat to marine calcifying organisms, yet experimental and field studies have found highly diverse responses among species and environments. Our understanding of the underlying drivers of differential responses to ocean acidification is currently limited by difficulties in directly observing and quantifying the mechanisms of bio-calcification. Here we present Raman spectroscopy techniques for quantifying the skeletal mineralogy and calcifying fluid chemistry of marine calcifying organisms such as corals, coralline algae, foraminifera, and fish (carbonate otoliths)...
January 28, 2019: Global Change Biology
Patrick Meister, Benjamin Brunner, Aude Picard, Michael E Böttcher, Bo Barker Jørgensen
Microbial life below the seafloor has changed over geological time, but these changes are often not obvious, as they are not recorded in the sediment. Sulphur (S) isotope values in pyrite extracted from a Plio- to Holocene sequence of the Peru Margin (Ocean Drilling Program, ODP, Site 1229) show a down-core pattern that correlates with the pattern of carbon (C) isotopes in diagenetic dolomite. Early formation of the pyrite is indicated by the mineralogical composition of iron, showing a high degree of pyritization throughout the sedimentary sequence...
January 24, 2019: Scientific Reports
Valentin R Troll, C Henry Emeleus, Graeme R Nicoll, Tobias Mattsson, Robert M Ellam, Colin H Donaldson, Chris Harris
Large-volume pyroclastic eruptions are not known from the basalt-dominated British Palaeogene Igneous Province (BPIP), although silicic magmatism is documented from intra-caldera successions in central volcanoes and from small-volume ash-layers in the associated lava fields. Exceptions are the Sgùrr of Eigg (58.7 Ma) and Òigh-sgeir pitchstones in the Inner Hebrides (>30 km apart), which have been conjectured to represent remnants of a single large silicic event. Currently available major element data from these outcrops differ, however, creating a need to test if the two pitchstones are really related...
January 24, 2019: Scientific Reports
Eric L S Marques, João C T Dias, Eduardo Gross, Adriana B de Cerqueira E Silva, Suzana R de Moura, Rachel P Rezende
The mineralogical composition of caves makes the environment ideal for inhabitation by microbes. However, the bacterial diversity in the cave ecosystem remains largely unexplored. In this paper, we described the bacterial community in an oxic chamber of the Sopradeira cave, an iron-rich limestone cave, in the semiarid region of Northeast Brazil. The microbial population in the cave samples was studied by 16S rDNA next-generation sequencing. A type of purple sulfur bacteria (PSB), Chromatiales, was found to be the most abundant in the sediment (57%), gravel-like (73%), and rock samples (96%)...
January 23, 2019: Microorganisms
Kristjan Leben, Riho Mõtlep, Peeter Paaver, Alar Konist, Tõnu Pihu, Päärn Paiste, Ivo Heinmaa, Gunnar Nurk, Edward J Anthony, Kalle Kirsimäe
Power generation and other industries using solid fossil fuels like coal, lignite, oil shale and peat are responsible for producing large quantities of solid residues that are often chemically reactive and/or unstable and are disposed in holding ponds and deposition sites. Stability and long-term behaviour of such deposits are typically studied in short-term laboratory experiments that cannot describe nor predict long-term changes taking place in these materials. Here, we study long-term (>40 years) transformations, in highly alkaline conditions, of the Ca-rich ash deposit in Estonia composed of oil shale processing residues from the Eesti power plant...
March 25, 2019: Science of the Total Environment
Valerie A Schoepfer, Edward D Burton, Scott G Johnston, Peter Kraal
Acid sulfate systems commonly contain the metastable ferric oxyhydroxysulfate mineral schwertmannite, as well as phosphate (PO4 3- ) - a nutrient that causes eutrophication when present in excess. However, acid sulfate systems often experience reducing conditions that destabilize schwertmannite. Under such conditions, the long-term fate of both schwertmannite and PO4 3- may be influenced by interactions during microbially-mediated Fe(III) and SO4 2- reduction. This study investigates the influence of PO4 3- on Fe(III) and SO4 2- reduction and the subsequent mineralogical transformation(s) in schwertmannite-rich systems exposed to reducing conditions...
March 20, 2019: Science of the Total Environment
Belem González-Grijalva, Diana Meza-Figueroa, Francisco M Romero, Agustín Robles-Morúa, Mercedes Meza-Montenegro, Leticia García-Rico, Roberto Ochoa-Contreras
Understanding the oral bioaccessibility of lead (Pb) present in soils in urbanized areas is important for the human exposure risk assessment. In particular, the role of the soil-mineralogy in the oral bioaccessibility has not been extensively studied. To investigate bioaccessibility, five types of periurban soils were collected, samples were spiked with the same amount of lead-chromates from traffic paint, and subjected to the in vitro Physiological Based Extraction Test (PBET). Ten samples of urban topsoils were collected at elementary schools playgrounds, Pb-bioaccessibility was measured, and a prediction equation for bioaccessibility was constructed...
March 20, 2019: Science of the Total Environment
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