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Dynamical X-ray diffraction imaging of voids in dislocation-free high-purity germanium single crystals
(
- Journal of Applied Crystallography
, 2020)
White-beam X-ray topography has been performed to provide direct evidence of micro-voids in dislocation-free high-purity germanium single crystals. The voids are visible because of a dynamical diffraction contrast. It is ...
Variscan ultra‐high‐pressure eclogite in the Upper Allochthon of the Rhodope Metamorphic Complex (Bulgaria)
(
- Terra Nova
, 2020-11-10)
The Rhodope Metamorphic Complex (RMC) in Bulgaria has been established as a Mesozoic ultra‐high‐pressure metamorphic province by findings of microdiamond in gneisses. Additionally, Variscan ultra‐high‐pressure metamorphism ...
Parameterizing Air-Water Gas Exchange in the Shallow, Microtidal New River Estuary
(
- Journal of Geophysical Research: Biogeosciences
, 2019)
Estuarine CO2 emissions are important components of regional and global carbon budgets, but assessments of this flux are plagued by uncertainties associated with gas transfer velocity (k) parameterization. We combined ...
Rock magnetics of carbonate systems–investigating palaeodune archives on Fuerteventura (Canary Islands)
(
- Journal of Quaternary Science
, 2020)
The mineral magnetic properties of Pleistocene aeolian dune sands from the island of Fuerteventura (Canary Islands, Spain) were studied in order to reconstruct the palaeoenvironmental evolution of Pleistocene climates ...
The modulated low-temperature structure of malayaite, CaSnOSiO4
(
- Acta Crystallographica Section B
, 2020)
The crystal structure of the mineral malayaite has been studied by single-crystal X-ray diffraction at a temperature of 20 K and by calculation of its phonon dispersion using density functional perturbation theory. The ...
Ice Age‐Holocene Similarity of Foraminifera‐Bound Nitrogen Isotope Ratios in the Eastern Equatorial Pacific
(
- Paleoceanography and Paleoclimatology
, 2021-05-19)
Bulk sediment δ15N records from the eastern tropical Pacific (ETP) extending back to the last ice age most often show low glacial δ15N, then a deglacial δ15N maximum, followed by a gradual decline to a late Holocene δ15N ...
Modelling the structural variation of quartz and germanium dioxide with temperature by means of transformed crystallographic data
(
- Acta Crystallographica Section B
, 2021-05-27)
The pseudocubic (PC) parameterization of O4 tetrahedra [Reifenberg & Thomas (2018). Acta Cryst. B74, 165–181] is applied to quartz (SiO2) and its structural analogue germanium dioxide (GeO2). In α‐quartz and GeO2, the ...
Comparison of In Situ and Ex Situ Equilibrium Passive Sampling for Measuring Freely Dissolved Concentrations of Parent and Alkylated Polycyclic Aromatic Hydrocarbons in Sediments
(
- Environmental Toxicology and Chemistry
, 2020-09-22)
Equilibrium passive sampling methods (EPSMs) allow quantification of freely dissolved contaminant concentrations (Cfree) in sediment porewater. Polydimethylsiloxane (PDMS) is a convenient sampling polymer that can be ...
Separation of the inelastic and elastic scattering in time‐of‐flight mode on the pinhole small‐angle neutron scattering diffractometer KWS‐2
(
- Journal of Applied Crystallography
, 2021-07-30)
To study and control the incoherent inelastic background in small‐angle neutron scattering, which makes a significant contribution to the detected scattering from hydrocarbon systems, the KWS‐2 small‐angle neutron scattering ...
Resolution of a bent‐crystal spectrometer for X‐ray free‐electron laser pulses: diamond versus silicon
(
- Acta Crystallographica Section A
, 2021-05-27)
The resolution function of a spectrometer based on a strongly bent single crystal (bending radius of 10 cm or less) is evaluated. It is shown that the resolution is controlled by two parameters: (i) the ratio of the lattice ...