Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience
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Data-mining for Crystal 'Gold' at SLAC's X-ray Laser | SLAC National Accelerator Laboratory

Data-mining for Crystal 'Gold' at SLAC's X-ray Laser | SLAC National Accelerator Laboratory | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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A new tool for analyzing mountains of data from SLAC’s Linac Coherent Lightsource (LCLS) X-ray laser can produce high-quality images of important proteins using fewer samples. Scientists hope to use it to  reveal the structures and functions of proteins that have proven elusive, as well as mine data from past experiments for new information.

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Lithotherapeutical research sources from antiquity to the mid-eighteenth century

Lithotherapeutical research sources from antiquity to the mid-eighteenth century | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Geopharmaceuticals have a recorded history of use by a wide range of cultures for over 3000 years.
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Influence of Atmospheric Processes on the Solubility and Composition of Iron in Saharan Dust

Influence of Atmospheric Processes on the Solubility and Composition of Iron in Saharan Dust | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Aerosol iron was examined in Saharan dust plumes using a combination of iron near-edge X-ray absorption spectroscopy and wet-chemical techniques.
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Some islands started in diamond-bearing regions under continents

Some islands started in diamond-bearing regions under continents | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Mantle melting, which leads to the formation of oceanic and continental crust, together with crust recycling through plate tectonics, are the primary processes that drive the chemical differentiation of the silicate Earth. The present-day mantle, as sampled by oceanic basalts, shows large chemical and isotopic variability bounded by a few end-member compositions. Among these, the HIMU end-member (having a high U/Pb ratio, μ) has been generally considered to represent subducted/recycled basaltic oceanic crust. However, this concept has been challenged by recent studies of the mantle source of HIMU magmas. For example, analyses of olivine phenocrysts in HIMU lavas indicate derivation from the partial melting of peridotite, rather than from the pyroxenitic remnants of recycled oceanic basalt. Here we report data that elucidate the source of these lavas: high-precision trace-element analyses of olivine phenocrysts point to peridotite that has been metasomatized by carbonatite fluids. Moreover, similarities in the trace-element patterns of carbonatitic melt inclusions in diamonds and HIMU lavas indicate that the metasomatism occurred in the subcontinental lithospheric mantle, fused to the base of the continental crust and isolated from mantle convection. Taking into account evidence from sulfur isotope data for Archean to early Proterozoic surface material in the deep HIMU mantle source, a multi-stage evolution is revealed for the HIMU end-member, spanning more than half of Earth’s history. Before entrainment in the convecting mantle, storage in a boundary layer, upwelling as a mantle plume and partial melting to become ocean island basalt, the HIMU source formed as Archean–early Proterozoic subduction-related carbonatite-metasomatized subcontinental lithospheric mantle.
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Transformation of galena to pyromorphite produces bioavailable sulfur for neutrophilic chemoautotrophy

Transformation of galena to pyromorphite produces bioavailable sulfur for neutrophilic chemoautotrophy | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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The Effect of Ca2+ and Mg2+ on the Dispersion and Flocculation Behaviors of Muscovite Particles

The Effect of Ca2+ and Mg2+ on the Dispersion and Flocculation Behaviors of Muscovite Particles | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The dispersion and flocculation behavior of muscovite suspensions in the presence of Ca2+ and Mg2+ are relevant for industrial processing of pre-concentrated muscovite from stone coal, a primary source of vanadium. In this study, the dispersion and flocculation behavior were investigated by means of sedimentation, zeta potential, and ion absorption experiments, as well as the force between particles and ion speciation calculations. The results indicated that the dispersion and flocculation behavior of muscovite particles without excess ions were in qualitative agreement with the classical DLVO theory. The muscovite particles aggregated mainly due to basal surface-edge interactions in acidic suspensions but were dispersed in alkaline suspension by electrostatic repulsion of the total particle surface. In acidic suspensions, the ability of muscovite to form dispersions of muscovite was increased with the decrease in the electrostatic attraction between the basal surface and the edge caused by the compression of the electric double layers withCa2+ and Mg2+. In alkaline suspension, the main adsorption form of Ca2+ and Mg2+ on muscovite surface was the ion-hydroxy complexes. The flocculation behavior of muscovite was affected by the static bridge effect of the ion-hydroxy complexes.
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Heterogeneous Nucleation and Growth of Nanoparticles at Environmental Interfaces

Heterogeneous Nucleation and Growth of Nanoparticles at Environmental Interfaces | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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In situ kinetic studies of the heterogeneous nucleation and growth behaviors of iron(III) (hydr)oxide, calcium carbonate, and manganese (hydr)oxide minerals in aqueous systems, are reviewed. In particular, the authors utilized simultaneous small-angle and grazing incidence small-angle X-ray scattering (SAXS/GISAXS) to investigate in situ and in real-time the effects of water chemistry and substrate identity on heterogeneously and homogeneously formed nanoscale precipitate size dimensions and total particle volume.
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The Effect of Chloride Ions on the Activity of Cerussite Surfaces

The Effect of Chloride Ions on the Activity of Cerussite Surfaces | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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Chloride ions were found to potentially increase activity of cerussite surfaces. Dissolution experiments, zeta potential measurements, X-ray photoelectron spectroscopy (XPS) studies, and density functional theory (DFT) computation were conducted in this study. Dissolution experiments showed that the lead ion concentrations in the NaCl solution system were lower than those in the deionized water system and that the lead ion concentrations in NaCl + Na2S aqueous systems decreased by approximately one order of magnitude compared with that in the Na2S system alone. Results of zeta potential measurements revealed that the pretreatment with chloride ions of cerussite caused a more positive zeta potential than that without chloride ions. XPS analysis results indicated that the number of lead ions on the mineral surface increased after cerussite was treated with chloride ions. Results of DFT computation implied that the number of lead atoms on the mineral surface increased and that the activity improved after PbCl+ was adsorbed onto the cerussite surface. The contribution of chloride ions to the activity on the mineral surface is attributed to the increase in the number of active sites and enhancement in the activity of these sites, resulting in improved sulfidization and flotation performance.
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Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures

Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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The authors report evidence for ancient life from a newly exposed outcrop of 3,700-Myr-old metacarbonate rocks in the ISB that contain 1–4-cm-high stromatolites—macroscopically layered structures produced by microbial communities.
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UCLA Cross|Section: Omar Yaghi

An in-depth interview with Omar Yaghi, a UCLA professor of chemistry and biochemistry and of molecular and medical pharmacology. Yaghi was recently ranke
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Molecular hydrogen in mantle minerals

Molecular hydrogen in mantle minerals | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
This observation suggests that during the accretion of the Earth, nebular H2 could have been delivered to the growing solid planet by direct dissolution in a magma ocean and subsequent incorporation in silicates.
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Particle Size Controls on Water Adsorption and Condensation Regimes at Mineral Surfaces

Particle Size Controls on Water Adsorption and Condensation Regimes at Mineral Surfaces | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Atmospheric water vapour interacting with hydrophilic mineral surfaces can produce water films of various thicknesses and structures.
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Water adsorption isotherms were predicted using models (1- or 2- term Freundlich and Do-Do models) describing an adsorption and a condensation regime, respectively pertaining to the binding of water onto mineral surfaces and water film growth by water-water interactions.
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Deep-Mined Geological Disposal of Radioactive Waste

Deep-Mined Geological Disposal of Radioactive Waste | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Elements, An International Magazine of Mineralogy, Geochemistry, and Petrology.
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A distinct source and differentiation history for Kolumbo submarine volcano #Santorini #Greece

A distinct source and differentiation history for Kolumbo submarine volcano #Santorini #Greece | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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This study reports the first detailed geochemical characterization of Kolumbo submarine volcano in order to investigate the role of source heterogeneity in controlling geochemical variability within the Santorini volcanic field in the central Aegean arc. Kolumbo, situated 15 km to the northeast of Santorini, last erupted in 1650 AD and is thus closely associated with the Santorini volcanic system in space and time. Samples taken by remotely-operated vehicle that were analyzed for major element, trace element and Sr-Nd-Hf-Pb isotope composition include the 1650 AD and underlying K2 rhyolitic, enclave-bearing pumices that are nearly identical in composition (73 wt.% SiO2, 4.2 wt.% K2O). Lava bodies exposed in the crater and enclaves are basalts to andesites (52–60 wt.% SiO2). Biotite and amphibole are common phenocryst phases, in contrast with the typically anhydrous mineral assemblages of Santorini. The strong geochemical signature of amphibole fractionation and the assimilation of lower crustal basement in the petrogenesis of the Kolumbo magmas indicates that Kolumbo and Santorini underwent different crustal differentiation histories and that their crustal magmatic systems are unrelated. Moreover, the Kolumbo samples are derived from a distinct, more enriched mantle source that is characterized by high Nb/Yb (>3) and low 206Pb/204Pb (<18.82) that has not been recognized in the Santorini volcanic products. The strong dissimilarity in both petrogenesis and inferred mantle sources between Kolumbo and Santorini suggests that pronounced source variations can be manifested in arc magmas that are closely associated in space and time within a single volcanic field.
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Video del momento histórico en que extraen el meteorito “Gancedo”

En las últimas horas, el Ministerio de Gobierno de la provincia, difundió a través de las redes sociales el momento culmine en que el equipo de trabaj
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Reflection of Socioeconomic Changes in Wastewater: Licit and Illicit Drug Use Patterns #Greece

Reflection of Socioeconomic Changes in Wastewater: Licit and Illicit Drug Use Patterns #Greece | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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A high increase in the use of psychoactive drugs was detected between 2010 and 2014, especially for antipsychotics (35-fold), benzodiazepines (19-fold), and antidepressants (11-fold).
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Recovery of Rare Earths and Other Valuable Metals From Bauxite Residue (Red Mud)

Recovery of Rare Earths and Other Valuable Metals From Bauxite Residue (Red Mud) | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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Bauxite residues contain considerable concentrations of rare-earth elements (REEs) and the recovery of these REEs together with(out) other metals and utilization of the generated residue in other applications (e.g., building materials) can solve the storage problem.
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First acidic macro-mesocellular aluminosilicate monolithic foams “SiAl(HIPE)” and their catalytic properties

First acidic macro-mesocellular aluminosilicate monolithic foams “SiAl(HIPE)” and their catalytic properties | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
A new type of acidic macrocellular and mesoporous silica–alumina foam is obtained via a one pot alkaline sol–gel route coupled with a concentrated emulsion-based templating technique. The mixed oxide monolith exhibits high surface acidity, translating into excellent performance in the acid-catalyzed dehydrat
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Protein–Mineral Interactions

Protein–Mineral Interactions | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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Over the Na+-birnessite basal surface the Gb1 structure is highly disturbed as a result of interaction with this birnessite surface. Unraveling of the Gb1 β-sheet at specific turns and a partial unraveling of the α-helix is observed over birnessite, which suggests specific vulnerable residue sites for oxidation or hydrolysis possibly leading to fragmentation.
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Structure and Dynamics of Water at Step Edges on the Calcite {101̅4} Surface

Structure and Dynamics of Water at Step Edges on the Calcite {101̅4} Surface | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Calcium sites along the step top edge can coordinate up to three water molecules, as compared with just the single water that can be adsorbed per calcium ion on the flat surface. Water residence times at calcium sites in the vicinity of the step span greater than 2 orders of magnitude, from tenths to several tens of ns, as compared to 2 and 0.2 ns for the flat surface and a calcium ion in aqueous solution, respectively.
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Groundwater quality and depletion in the Indo-Gangetic Basin mapped from in situ observations

Groundwater quality and depletion in the Indo-Gangetic Basin mapped from in situ observations | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
This basin-wide synthesis of in situ groundwater observations provides the spatial detail essential for policy development, and the historical context to help evaluate recent satellite gravity data.
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The New Chemistry of Metal-Organic Frameworks (MOF's)

Omar Yaghi, Chemistry Professor, UC Berkeley Director, Molecular Foundry, Berkeley Lab
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The Influence of Impurity Monovalent Cations Adsorption on Reconstructed Chalcopyrite (001)-S Surface in Leaching Process

The Influence of Impurity Monovalent Cations Adsorption on Reconstructed Chalcopyrite (001)-S Surface in Leaching Process | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
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Hydrometallurgical processing of chalcopyrite is hindered predominantly due to the passivation layers formed on the chalcopyrite surface. However, the effects of impurity cations released from the gangue are not yet well understood. Density functional theory (DFT) calculations were carried out to investigate monovalent cations of Na+ and K+ on chalcopyrite (001)-S surface using Materials Studio. The results show that the 3d orbital of Fe and 3p orbital of S predominantly contribute to their activities during chalcopyrite oxidation and dissolution processes. In addition, SO42− is more likely to be adsorbed on one Fe site in the presence of Na+, while it is preferentially adsorbed on two Fe sites in the presence of K+. However, the adsorption of both Na2SO4 and K2SO4 on the chalcopyrite (001)-S surface contributes to the breakage of S–S bonds, indicating that the impurity cations of Na+ and K+ are beneficial to chalcopyrite leaching in a sulfuric environment. The adsorption energy and partial density of states (PDOS) analyses further indicate that the adsorption of Na2SO4 on chalcopyrite (001)-S surface is favored in both -BB (bidentate binuclear ) and -BM (bidentate mononuclear) modes, compared to the adsorption of K2SO4.
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Origin of uranium isotope variations in early solar nebula condensates

Origin of uranium isotope variations in early solar nebula condensates | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
High-temperature condensates found in meteorites display uranium isotopic variations (235U/238U), which complicate dating the solar system’s formation and whose origin remains mysterious. It is possible that these variations are due to the decay of the short-lived radionuclide 247Cm ( t 1/2 = 15.6 My) into 235U, but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesses of 235U reaching ~+6% relative to average solar system composition, which can only be due to the decay of 247Cm. This allows us to constrain the 247Cm/235U ratio at solar system formation to (1.1 ± 0.3) × 10−4. This value provides new clues on the universality of the nucleosynthetic r -process of rapid neutron capture.
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Restraining Na-Montmorillonite Delamination in Water by Adsorption of Sodium Dodecyl Sulfate or Octadecyl Trimethyl Ammonium Chloride on the Edges

Restraining Na-Montmorillonite Delamination in Water by Adsorption of Sodium Dodecyl Sulfate or Octadecyl Trimethyl Ammonium Chloride on the Edges | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The delamination of montmorillonite in water leads to sliming in ore slurry, which is detrimental to mineral flotation and solid/water separation. In this work, the delamination of Na-montmorillonite (Na-MMT) has been restrained by sodium dodecyl sulfate (SDS) or octadecyl trimethyl ammonium chloride (1831) through the adsorption on the edge of the mineral. The experimental results have shown that the pretreatment by adding SDS and 1831 could greatly reduce the Stokes size percentage of −1.1 µm particles in the aqueous Na-MMT suspension. From the X-ray diffractometer (XRD) results, the interlayer spacing of the MMT pre-treated by SDS and 1831 is smaller than that of original MMT particles. Adsorption position of SDS and 1831 on MMT surfaces was analyzed by the measurements of adsorption capacity of SDS and 1831, inductively-coupled plasma spectra, and zeta potential before and after the plane surface of MMT was covered with tetraethylenepentaminecopper ([Cu(tetren)]2+). The results indicated that SDS and 1831 are adsorbed on the edge and the whole surface of Na-MMT, respectively. Delamination of MMT could be well restrained by the adsorption of SDS and 1831 on the edges of MMT.
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Minerals with metal-organic framework structures

Minerals with metal-organic framework structures | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Metal-organic frameworks (MOFs) are an increasingly important family of advanced materials based on open, nanometer-scale metal-organic architectures, whose design and synthesis are based on the directed assembly of carefully designed subunits. We now demonstrate an unexpected link between mineralogy and MOF chemistry by discovering that the rare organic minerals stepanovite and zhemchuzhnikovite exhibit structures found in well-established magnetic and proton-conducting metal oxalate MOFs. Structures of stepanovite and zhemchuzhnikovite, exhibiting almost nanometer-wide and guest-filled apertures and channels, respectively, change the perspective of MOFs as exclusively artificial materials and represent, so far, unique examples of open framework architectures in organic minerals.
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