Water electrolysis: from textbook knowledge to the latest scientific strategies and industrial developments.

Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO footprint.

Composition Analysis by STEM-EDX of Ternary Semiconductors by Internal References.

A practical method to determine the composition within ternary heterostructured semiconductor compounds using energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy is presented. The method requires minimal external input factors such as user-determined or calculated sensitivity factors by incorporating a known compositional relationship, here a fixed stoichiometric ratio in III–V compound semiconductors. The method is demonstrated for three different systems; AlGaAs/GaAs, GaAsSb/GaAs, and InGaN/GaN with three different specimen geometries and compared to conventional quantification approaches.

The population genomic basis of geographic differentiation in North American common ragweed ( L.).

Common ragweed ( L.) is an invasive, wind-pollinated plant nearly ubiquitous in disturbed sites in its eastern North American native range and present across growing portions of Europe, Africa, Asia, and Australia. Phenotypic divergence between European and native-range populations has been described as rapid evolution.

Lithium ion-water clusters in strong electric fields: a quantum chemical study.

We use density functional theory to investigate the impact that strong electric fields have on the structure and energetics of small lithium ion-water clusters, Li(+)·nH2O, with n = 4 or 6. We find that electric field strengths of ∼0.5 V/Å are sufficient to break the symmetry of the n = 4 tetrahedral energy minimum structure, which undergoes a transformation to an asymmetric cluster consisting of three water molecules bound to lithium and one additional molecule in the second solvation shell.

Spatial and temporal genetic structure of a river-resident Atlantic salmon (Salmo salar) after millennia of isolation.

The river-resident Salmo salar ("småblank") has been isolated from other Atlantic salmon populations for 9,500 years in upper River Namsen, Norway. This is the only European Atlantic salmon population accomplishing its entire life cycle in a river. Hydropower development during the last six decades has introduced movement barriers and changed more than 50% of the river habitat to lentic conditions.

Real-time in situ Mueller matrix ellipsometry of GaSb nanopillars: observation of anisotropic local alignment.

The formation of GaSb nanopillars by low energy ion sputtering is studied in real-time by spectroscopic Mueller matrix ellipsometry, from the initial formation in the smooth substrate until nanopillars with a height of 200-300 nm are formed. As the nanopillar height increased above 100 nm, coupling between orthogonal polarization modes was observed. Ex situ angle resolved Mueller polarimetry measurements revealed a 180° azimuth rotation symmetry in the off-diagonal Mueller elements, which can be explained by a biaxial material with different dielectric functions εx and εy in a plane parallel to the substrate.