Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience
8.6K views | +2 today
Follow
 
Scooped by Ath Godelitsas
onto Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience
Scoop.it!

Remote sensing of surface molecules: the infrared Scanning Tunneling Microscope

Remote sensing of surface molecules: the infrared Scanning Tunneling Microscope | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Surface tunneling microscopy offers a new way to obtain vibrational spectra of adsorbed molecules.
Ath Godelitsas's insight:

Two University of California at Berkeley research groups, one with experience in Scanning Tunneling Microscope (STM), and the other, specialists in laser design and applications, set up a highly stable, pulsed laser source and pointed it on a spot of a gold surface covered by a particular molecule. Rather than placing their STM tip at the laser spot, they position it on the substrate approximately one millimeter away (i.e., some 1 million molecular diameters). Nevertheless, when tuning the frequency of the laser light to resonate with a molecular vibrational mode, they find a signal in the STM current. This they attribute to the molecule absorbing the light, becoming vibrationally excited, and then dissipating the vibrational energy to the substrate. Remarkably, on the particular molecules they chose—tetramantanes—the resonance turns out to be extremely sharp, allowing for single wave-number resolution in their vibrational spectroscopy, far better than in prior STM-based approaches.

more...
No comment yet.
Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience
Your new post is loading...
Your new post is loading...
Scooped by Ath Godelitsas
Scoop.it!

Cycles of nutrient trace elements in the Phanerozoic ocean

Cycles of nutrient trace elements in the Phanerozoic ocean | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Ath Godelitsas's insight:
Share your insight
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Process Mineralogy 2017

Process Mineralogy 2017 | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Petrolab are proud sponsors of Process Mineralogy 2017 in Cape Town and have the privilege of presenting two papers at the conference.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Three-dimensional preservation of cellular and subcellular structures suggests 1.6 billion-year-old crown-group red algae

Three-dimensional preservation of cellular and subcellular structures suggests 1.6 billion-year-old crown-group red algae | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
The authors studied exquisitely preserved fossil communities from ~1.6 billion-year-old sedimentary rocks in central India representing a shallow-water marine environment characterized by photosynthetic biomats.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

International School on Biological Crystallization - ISBC Granada

International School on Biological Crystallization - ISBC Granada | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The ISBC2017 belong to a series of International Crystallization Schools organized yearly every last week of May since 2006 in Granada. The whole series of ISC and ISBC are sponsored by the International Union of Crystallography (IUCr), The Ministry of Economy and Competitiveness of Spain, The International University Menendez Pelayo, The University of Granada, and the Specialized Group of Crystallography and Crystal Growth (GE3C) of the Spanish Royal Society of Chemistry, and it is supported by the Working Party on Crystallization (WPC) of the European Federation of Chemical Engineers and the International Organization of Crystal Growth.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

The integral role of iron in ocean biogeochemistry

The integral role of iron in ocean biogeochemistry | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The micronutrient iron is now recognized to be important in regulating the magnitude and dynamics of ocean primary productivity, making it an integral component of the ocean’s biogeochemical cycles. In this Review, we discuss how a recent increase in observational data for this trace metal has challenged the prevailing view of the ocean iron cycle. Instead of focusing on dust as the major iron source and emphasizing iron’s tight biogeochemical coupling to major nutrients, a more complex and diverse picture of the sources of iron, its cycling processes and intricate linkages with the ocean carbon and nitrogen cycles has emerged.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

The quest to crystallize time

The quest to crystallize time | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Bizarre forms of matter called time crystals were supposed to be physically impossible. Now they’re not.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

New Insights into the Chemical and Isotopic Composition of Human-Body Biominerals. II: COM Kidney Stones from #Greece

New Insights into the Chemical and Isotopic Composition of Human-Body Biominerals. II: COM Kidney Stones from #Greece | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
We have analyzed kidney stones from patients from Greece in which the mineral phase was calcium oxalate monohydrate (COM) as identified by powder-XRD and FTIR spectra. SEM-EDS analysis revealed microscale-COM crystal aggregates mixed with organic/biological matter. XRF revealed that in addition to Ca (max. ca. 21.4 wt. %; av. ca. 21 wt.%) and Sr (max. 35 ppm; av. 34 ppm), there were significant levels of heavy metal impurities, namely Zn (max. 214 ppm; av. 204 ppm), Pb (max. 149 ppm; av. 136 ppm), Fe (max. 136 ppm; av. 132 ppm) and Cu (max. 17 ppm; av. 15 ppm), as well as minor amounts of Br. As identified by IRMS, all three examined kidney stones presented a very light δ13C signature (average δ13C ca. -25.4‰ PDB) as compared to previously reported data on kidney stones from humans from different geographical locations. The δ18O values averaged ca. -7.31‰ PDB. With regard to radioactive isotopes, HR γ-ray spectrometry demonstrated the existence of the natural radionuclides 214Pb and 214Bi due to 238U-series, and also an additional amount of 40Κ. We conclude that these kidney stones from southeastern Europe are enriched in essential biometals (Zn and Fe), and also contain a high content of harmful heavy metals such as Pb, and traces of U. This elemental composition may be related to a toxic diet and/or environmental pollution.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Centre of Excellence in Ore Deposits - University of Tasmania, Australia

Centre of Excellence in Ore Deposits - University of Tasmania, Australia | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Large gem diamonds from metallic liquid in Earth’s deep mantle

Large gem diamonds from metallic liquid in Earth’s deep mantle | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it

Standing at ~7-centimeters tall, this 404.2-carat rough diamond was recovered from the Lulo mine, Angola, in February 2016. Evidence from the interior of such large gem diamonds suggests that these diamonds grow from an iron-nickel metallic liquid in Earth's deep convecting mantle. The presence of metal in regions of the deep mantle has broad implications for Earth's geologic evolution. See page 1403. Photo: © SPOA/Orel SIMON

more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Microbial diversity in the deep-subsurface hydrothermal aquifer feeding the giant gypsum crystal-bearing Naica Mine, Mexico

Microbial diversity in the deep-subsurface hydrothermal aquifer feeding the giant gypsum crystal-bearing Naica Mine, Mexico | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The Naica Mine in northern Mexico is famous for its giant gypsum crystals, which may reach up to 11 m long and contain fluid inclusions that might have captured microorganisms during their formation. These crystals formed under particularly stable geochemical conditions in cavities filled by low salinity hydrothermal water at 54–58°C. scription
Ath Godelitsas's insight:
Share your insight
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Dissolution and Sorption Processes on the Surface of Calcite in the Presence of High Co2+ Concentration

Dissolution and Sorption Processes on the Surface of Calcite in the Presence of High Co2+ Concentration | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
The interaction of the calcite surface with Co2+-rich aqueous solutions ([Co2+aq]initial = 1000 ppm, i.e., ca. 17 mM) was investigated by means of macroscopic experiments and surface spectroscopic techniques. In the case of the macroscopic experiments, calcite powder and monocrystals were immersed into solutions for different time periods (from 1 min to one month). The Ca concentrations in the filtrates was measured by means of atomic absorption spectrometry (AAS) while the interacted solids were studied using a combination of X-ray photoelectron spectroscopy (XPS) and 12C-rutherford backscattering spectrometry (12C-RBS). The macroscopic data showed a characteristic surface dissolution process, in parallel to the surface sorption processes. Adsorption and co-precipitation were seen for almost the entire immersion period for both calcite powder and monocrystals. The surface study by XPS (analyzed at a depth of approximately 12 nm) suggested that adsorption takes place in the first hour of the interaction, followed by incorporation of Co2+ into calcite surface layers, leading to the formation of a Co2+-bearing surface (co)precipitate, which occurs over a period of hours and days. The 12C-RBS measurements on calcite { 101¯4 } indicated that the thickness of this surface co-precipitate was 270 nm after one day and then stabilized at 320 nm after more than a week.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

The Deep Carbon Observatory

The Deep Carbon Observatory is a global community of multi-disciplinary scientists unlocking the inner secrets of Earth through investigations into life
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Carbon Sequestration in Olivine and Basalt Powder Packed Beds

Carbon Sequestration in Olivine and Basalt Powder Packed Beds | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Magnesite formed in experiments with olivine, and Mg- and Ca-bearing siderite formed in experiments with flood basalt.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Evidence for early life in Earth’s oldest hydrothermal vent precipitates

Evidence for early life in Earth’s oldest hydrothermal vent precipitates | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
The authors describe putative fossilized microorganisms that are at least 3,770 million and possibly 4,280 million years old in ferruginous sedimentary rocks, interpreted as seafloor-hydrothermal vent-related precipitates, from the Nuvvuagittuq belt in Quebec, Canada.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Biomimetic mineral self-organization from silica-rich spring waters

Biomimetic mineral self-organization from silica-rich spring waters | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Purely inorganic reactions of silica, metal carbonates, and metal hydroxides can produce self-organized complex structures that mimic the texture of biominerals, the morphology of primitive organisms, and that catalyze prebiotic reactions. To date, these fascinating structures have only been synthesized using model solutions. We report that mineral self-assembly can be also obtained from natural alkaline silica-rich water deriving from serpentinization. Specifically, we demonstrate three main types of mineral self-assembly: (i) nanocrystalline biomorphs of barium carbonate and silica, (ii) mesocrystals and crystal aggregates of calcium carbonate with complex biomimetic textures, and (iii) osmosis-driven metal silicate hydrate membranes that form compartmentalized, hollow structures. Our results suggest that silica-induced mineral self-assembly could have been a common phenomenon in alkaline environments of early Earth and Earth-like planets.
Ath Godelitsas's insight:
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Diamond formation in the deep lower mantle: a high-pressure reaction of MgCO3 and SiO2

Diamond formation in the deep lower mantle: a high-pressure reaction of MgCO3 and SiO2 | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
The authors determined the phase relations in the MgCO3-SiO2 system up to 152 GPa and 3,100 K using a double sided laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Manganese Oxide Reactions on Ni and Zn Speciation

Manganese Oxide Reactions on Ni and Zn Speciation | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Layered Mn oxide minerals (phyllomanganates) often control trace metal fate in natural systems. The strong uptake of metals such as Ni and Zn by phyllomanganates results from adsorption on or incorporation into vacancy sites.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Iron entangled : Nature Geoscience : Nature Research

Iron entangled : Nature Geoscience : Nature Research | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Iron is an essential fuel for life in the oceans. The influence of this element on biogeochemistry [mdash] and nitrogen cycling in particular [mdash] varies across environments and time.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

On the mineralogy of the “Anthropocene Epoch”

On the mineralogy of the “Anthropocene Epoch” | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The “Anthropocene Epoch” has been proposed as a new post-Holocene geological time interval—a period characterized by the pervasive impact of human activities on the geological record. Prior to the influence of human technologies, the diversity and distribution of minerals at or near Earth’s surface arose through physical, chemical, and/or biological processes. Since the advent of human mining and manufacturing, particularly since the industrial revolution of the mid-eighteenth century, mineral-like compounds have experienced a punctuation event in diversity and distribution owing to the pervasive impact of human activities. We catalog 208 mineral species approved by the International Mineralogical Association that occur principally or exclusively as a consequence of human processes. At least three types of human activities have affected the diversity and distribution of minerals and mineral-like compounds in ways that might be reflected in the worldwide stratigraphic record. The most obvious influence is the widespread occurrence of synthetic mineral-like compounds, some of which are manufactured directly for applications (e.g., YAG crystals for lasers; Portland cement) and others that arise indirectly (e.g., alteration of mine tunnel walls; weathering products of mine dumps and slag). A second human influence on the distribution of Earth’s near-surface minerals relates to large-scale movements of rocks and sediments—sites where large volumes of rocks and minerals have been removed. Finally, humans have become relentlessly efficient in redistributing select natural minerals, such as gemstones and fine mineral specimens, across the globe. All three influences are likely to be preserved as distinctive stratigraphic markers far into the future.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Dated eclogitic diamond growth zones reveal variable recycling of crustal carbon through time

Dated eclogitic diamond growth zones reveal variable recycling of crustal carbon through time | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it

• Rb–Sr and Sm–Nd isotope systematics of individual silicate inclusions in diamonds.
• Sm–Nd ages from 0.1 to 2.3 Ga, with up to 2 Ga differences in individual diamonds.
• Relationship between 87Sr/86Sr of inclusion and δ13Cδ13C of diamond host.
• Variations in C–Sr isotope ratios controlled by regional geological events.
• Older diamonds more likely to have light δ13Cδ13C.

Ath Godelitsas's insight:
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Iron persistence in a distal hydrothermal plume supported by dissolved-particulate exchange

Iron persistence in a distal hydrothermal plume supported by dissolved-particulate exchange | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
The largest known hydrothermal plume moves dissolved iron halfway across the Pacific. In situ measurements show that dissolved and particulate iron transport is facilitated by reversible exchange of dissolved iron onto organic compounds.
Ath Godelitsas's insight:
Share your insight
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Caesium-rich micro-particles: A window into the meltdown events at the Fukushima Daiichi Nuclear Power Plant

Caesium-rich micro-particles: A window into the meltdown events at the Fukushima Daiichi Nuclear Power Plant | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
All of the CsMPs (with sizes of 2.0–3.4 μm) comprise SiO2 glass matrices and ~10-nm-sized Zn–Fe-oxide nanoparticles associated with a wide range of Cs concentrations (1.1–19 wt% Cs as Cs2O).
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Nuclear explosions could tell us why the moon has no water

Scientists are studying debris from the Trinity nuclear test to figure out how the moon lost its water.
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Solving the mysteries of climate

Did you know that a tiny nanoparticle size of less than 0.000000001 meters can help us predict massive global changes? Watch a video of a new researc
more...
No comment yet.
Scooped by Ath Godelitsas
Scoop.it!

Uranium(IV) adsorption by natural organic matter in anoxic sediments

Uranium(IV) adsorption by natural organic matter in anoxic sediments | Mineralogy, Geochemistry, Mineral Surfaces & Nanogeoscience | Scoop.it
Empty description
Ath Godelitsas's insight:
The authors show that adsorption to organic carbon and organic carbon-coated clays dominate U(IV) speciation in an organic-rich natural substrate under field-relevant conditions.
more...
No comment yet.