International Journal of Materials Research, Sep 1, 1993
Tellurium vapor pressures were determined by an isopiestic method for solid titanium-tellurium al... more Tellurium vapor pressures were determined by an isopiestic method for solid titanium-tellurium alloys with NiAs-derivative crystal structures between 55 and 66.7 at.% Te and between 825 and 1350 K. Activities and partial molar enthalpies of tellurium were derived from them. The results are interpreted in terms of a statistical theoretical model, based on a Cr 3 S 4 type superstructure (with a certain ordering pattern of titanium vacancies) for Ti 3 Te 4 . The model curve describing the experimental activity data is compatible with the assumption of a continuous transition from the Cr 3 S 4 type superstructure (at 57.1 at.% Te) through the V 5 Se 8 type superstructure (at 61.5 at.% Te) to the CdI 2 structure (at 66.7 at.% Te)
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
A statistical thermodynamic model of the Wagner-Schottky type is applied in order to determine th... more A statistical thermodynamic model of the Wagner-Schottky type is applied in order to determine the defect pattern in the β′-FeAl phase. Model calculations based on the concentration dependence of the thermodynamic activity of Al yield the following defect concentrations for the composition Fe50.5Al49.5 at 1338 K: 1.76 ± 0.20% of all lattice sites are vacant, 3.36 ± 0.40% of the
Organic soils in the Arctic-boreal region produce small aquatic humic ligands (SAHLs), a category... more Organic soils in the Arctic-boreal region produce small aquatic humic ligands (SAHLs), a category of naturally occurring complexing agents for iron. Every year, large amounts of SAHLs-loaded with iron mobilized in river basins-reach the oceans via river runoff. Recent studies have shown that a fraction of SAHLs belong to the group of strong iron-binding ligands in the ocean. That means, their Fe(III) complexes withstand dissociation even under the conditions of extremely high dilution in the open ocean. Fe(III)-loaded SAHLs are prone to UV-photoinduced ligand-to-metal charge-transfer which leads to disintegration of the complex and, as a consequence, to enhanced concentrations of bioavailable dissolved Fe(II) in sunlit upper water layers. On the other hand, in water depths below the penetration depth of UV, the Fe(III)-loaded SAHLs are fairly resistant to degradation which makes them ideally suited as long-lived molecular transport vehicles for river-derived iron in ocean currents. At locations where SAHLs are present in excess, they can bind to iron originating from various sources. For example, SAHLs were proposed to contribute substantially to the stabilization of hydrothermal iron in deep North Atlantic waters. Recent discoveries have shown that SAHLs, supplied by the Arctic Great Rivers, greatly improve dissolved iron concentrations in the Arctic Ocean and the North Atlantic Ocean. In these regions, SAHLs play a critical role in relieving iron limitation of phytoplankton, thereby supporting the oceanic sink for anthropogenic CO2. The present Critical Review describes the most recent findings and highlights future research directions.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Journal of Materials Research, Sep 1, 1993
Tellurium vapor pressures were determined by an isopiestic method for solid titanium-tellurium al... more Tellurium vapor pressures were determined by an isopiestic method for solid titanium-tellurium alloys with NiAs-derivative crystal structures between 55 and 66.7 at.% Te and between 825 and 1350 K. Activities and partial molar enthalpies of tellurium were derived from them. The results are interpreted in terms of a statistical theoretical model, based on a Cr 3 S 4 type superstructure (with a certain ordering pattern of titanium vacancies) for Ti 3 Te 4 . The model curve describing the experimental activity data is compatible with the assumption of a continuous transition from the Cr 3 S 4 type superstructure (at 57.1 at.% Te) through the V 5 Se 8 type superstructure (at 61.5 at.% Te) to the CdI 2 structure (at 66.7 at.% Te)
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
A statistical thermodynamic model of the Wagner-Schottky type is applied in order to determine th... more A statistical thermodynamic model of the Wagner-Schottky type is applied in order to determine the defect pattern in the β′-FeAl phase. Model calculations based on the concentration dependence of the thermodynamic activity of Al yield the following defect concentrations for the composition Fe50.5Al49.5 at 1338 K: 1.76 ± 0.20% of all lattice sites are vacant, 3.36 ± 0.40% of the
Organic soils in the Arctic-boreal region produce small aquatic humic ligands (SAHLs), a category... more Organic soils in the Arctic-boreal region produce small aquatic humic ligands (SAHLs), a category of naturally occurring complexing agents for iron. Every year, large amounts of SAHLs-loaded with iron mobilized in river basins-reach the oceans via river runoff. Recent studies have shown that a fraction of SAHLs belong to the group of strong iron-binding ligands in the ocean. That means, their Fe(III) complexes withstand dissociation even under the conditions of extremely high dilution in the open ocean. Fe(III)-loaded SAHLs are prone to UV-photoinduced ligand-to-metal charge-transfer which leads to disintegration of the complex and, as a consequence, to enhanced concentrations of bioavailable dissolved Fe(II) in sunlit upper water layers. On the other hand, in water depths below the penetration depth of UV, the Fe(III)-loaded SAHLs are fairly resistant to degradation which makes them ideally suited as long-lived molecular transport vehicles for river-derived iron in ocean currents. At locations where SAHLs are present in excess, they can bind to iron originating from various sources. For example, SAHLs were proposed to contribute substantially to the stabilization of hydrothermal iron in deep North Atlantic waters. Recent discoveries have shown that SAHLs, supplied by the Arctic Great Rivers, greatly improve dissolved iron concentrations in the Arctic Ocean and the North Atlantic Ocean. In these regions, SAHLs play a critical role in relieving iron limitation of phytoplankton, thereby supporting the oceanic sink for anthropogenic CO2. The present Critical Review describes the most recent findings and highlights future research directions.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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