A5031084988- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- Astro and Planetary Science
- Planetary Science and Exploration
- earthquake and tectonic studies
- Geology and Paleoclimatology Research
- Geomagnetism and Paleomagnetism Studies
- Diamond and Carbon-based Materials Research
- Crystal Structures and Properties
- Clay minerals and soil interactions
- Mineralogy and Gemology Studies
- Geochemistry and Elemental Analysis
- Metal Extraction and Bioleaching
- Geochemistry and Geologic Mapping
- Paleontology and Stratigraphy of Fossils
- Iron oxide chemistry and applications
- Laser-induced spectroscopy and plasma
- Glass properties and applications
- Space Exploration and Technology
- Boron and Carbon Nanomaterials Research
- X-ray Diffraction in Crystallography
- Electronic and Structural Properties of Oxides
- Hydrocarbon exploration and reservoir analysis
- Metallurgical Processes and Thermodynamics
- Advancements in Battery Materials
Friedrich Schiller University Jena
2015-2024
University of Hawaiʻi at Mānoa
2017-2024
Carl Zeiss (Germany)
2014-2023
University of Bayreuth
2005-2014
Grantmakers for Effective Organizations
2010
Centre National de la Recherche Scientifique
1994-2009
Umeå University
2009
University of Szeged
2009
University of Tübingen
2007
University of Colorado Boulder
2007
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. preliminary examination these samples shows that the nonvolatile portion is an unequilibrated assortment materials have both presolar solar system origin. contains abundance silicate grains are much larger than predictions interstellar grain models, many high-temperature minerals appear formed in inner regions nebula. Their presence a proves formation included...
The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by Stardust spacecraft appear be weakly constructed mixtures nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, metal, and accessory phases. very wide range olivine low-Ca pyroxene compositions in requires a formation conditions, probably reflecting different locations protoplanetary disk. restricted compositional ranges for absence hydrous phases...
Abstract— Quartz, as a ubiquitous mineral constituent of the Earth's crust, displays greatest variety well‐defined residual shock effects among all rock‐forming minerals. It represents an important and most reliable barometer thermometer for terrestrial impact formations. In this paper, current status knowledge about nature, origin, experimental pressure‐temperature calibration shock‐induced deformations phase transformations is reviewed natural conditions.
Titanium L3,2 and O K electron energy loss near-edge structures (ELNES) of seven Ti oxides have been measured in a transmission microscope to obtain information on the valence state site geometry Ti. The coordination all phases studied is octahedral, whereas states occurring are Ti2+, Ti3+, Ti4+. Effects polyhedra distortions particularly observed for two with mixed Ti3+-Ti4+ state, i.e., Magnéli Ti4O7 Ti5O9. A prominent pre-peak L3 edge attributed orthorhombic these compounds, leading...
Abstract The intercalation of solvated sodium ions into graphite from ether electrolytes was recently discovered to be a surprisingly reversible process. mechanisms this “cointercalation reaction” are poorly understood and commonly accepted design criteria for electrodes do not seem apply. excellent reversibility despite the large volume expansion, small polarization puzzling role solid electrolyte interphase (SEI) particularly striking. Here, in situ electrochemical dilatometry, online mass...
The distributions of major and minor elements in Earth's core mantle were primarily established by high pressure, temperature metal–silicate partitioning during segregation. behaviors moderately siderophile can be used to constrain the pressure–temperature conditions formation core's composition. We performed experiments study Ni, Co, V, Cr, Si, O between silicate melt Fe-rich metallic a multianvil press diamond anvil cell, up 100 GPa 5700 K. Combining our new results with data from 18...
Abstract— The occurrence of shock metamorphosed quartz is the most common petrographic criterion for identification terrestrial impact structures and lithologies. Its utility due to its almost ubiquitous in rocks, overall stability fact that a variety metamorphic effects, occurring over range pressures, have been well documented. These effects generally duplicated recovery experiments and, thus, serve as pressure barometers. After reviewing general character quartz, differences between...
Plate tectonics is based on the concept of rigid lithosphere plates sliding a mechanically weak asthenosphere. Many models assume that weakness asthenosphere related to presence small amounts hydrous melts. However, mechanism may cause melting in not well understood. We show coincides with zone where water solubility mantle minerals has pronounced minimum. The minimum due sharp decrease aluminous orthopyroxene depth, whereas olivine continuously increases pressure. Melting therefore be...
Abstract— We compare the observed composition ranges of olivine, pyroxene, and Fe‐Ni sulfides in Wild 2 grains with those from chondritic interplanetary dust particles (IDPs) chondrite classes to explore whether these data suggest affinities known hydrous materials particular. olivine has an extremely wide range, Fa 0–96 , a pronounced frequency peak at 1 . The range displayed by low‐calcium pyroxene is also very extensive, Fs 48 0 significant centered 5 These are as broad or broader than...
Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through collective process called space weathering. The return samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study space-weathering signatures on most abundant type inner solar system body: C-type asteroid, composed materials largely unchanged since formation...
Abstract Transmission electron microscopy analyses of Hayabusa2 samples show that Ryugu organic matter exhibits a range morphologies, elemental compositions, and carbon functional chemistries consistent with those carbonaceous chondrites have experienced low‐temperature aqueous alteration. Both nanoglobules diffuse are abundant. Non‐globular particles also present, including some contain nanodiamond clusters. Diffuse is finely distributed in around phyllosilicates, forms coatings on other...
Fe-Mg interdiffusion coefficients for (Mg,Fe)SiO3 perovskite have been measured at pressures of 22 to 26 gigapascals and temperatures between 1973 2273 kelvin. Perovskite is as slow Si self-diffusion orders magnitude slower than diffusion in other mantle minerals. Length scales over which chemical heterogeneities can homogenize, throughout the depth range lower mantle, are limited a few meters even on time equivalent age Earth. Heterogeneities therefore only equilibrate chemically when they...
Research Article| February 01, 2012 Shock Metamorphism of Minerals Falko Langenhorst; Langenhorst 1Institut für Geowissenschaften, Friedrich-Schiller-Universität JenaCarl-Zeiss-Promenade 10, D-07745 Jena, GermanyE-mail: falko.langenhorst@uni-jena.de Search for other works by this author on: GSW Google Scholar Alex Deutsch 2Institut Planetologie, Westfälische Wilhelms-Universität MünsterWilhelm-Klemm-Straße D-48149 Münster, deutsca@uni-muenster.de Author and Article Information Publisher:...
Abstract Extraterrestrial iron sulfide is a major mineral reservoir of the cosmochemically and astrobiologically important elements sulfur. Sulfur depletion on asteroids long-standing, yet unresolved phenomenon that fundamental importance for asteroid evolution sulfur delivery to Earth. Understanding chemistry such environments requires insight into behavior sulfides exposed space. Here we show troilite (FeS) grains recovered from regolith 25143 Itokawa have lost during long-term space...
Abstract Light emission from CaZnOS:Nd 3+ by high‐intensity ultrasound excitation is demonstrated. Acoustic power and duty ratio enable simultaneous control of the degree (local) thermo‐acoustic heating in isothermal or nonisothermal conditions. The Nd‐related photoemission provides direct thermometric feedback at an absolute sensitivity on order 10 −4 K −1 , within physiological temperature range. From individual dependence persistent luminescence mechanoluminescence, both effects are...