19 research outputs found
Recommended from our members
Sub-nanometer surface chemistry and orbital hybridization in lanthanum-doped ceria nanocatalysts revealed by 3D electron microscopy
Surface chemical composition, electronic structure, and bonding characteristics determine catalytic activity but are not resolved for individual catalyst particles by conventional spectroscopy. In particular, the nano-scale three-dimensional distribution of aliovalent lanthanide dopants in ceria catalysts and their effect on the surface electronic structure remains unclear. Here, we reveal the surface segregation of dopant cations and oxygen vacancies and observe bonding changes in lanthanum-doped ceria catalyst particle aggregates with sub-nanometer precision using a new model-based spectroscopic tomography approach. These findings refine our understanding of the spatially varying electronic structure and bonding in ceria-based nanoparticle aggregates with aliovalent cation concentrations and identify new strategies for advancing high efficiency doped ceria nano-catalysts.We thank Alex Eggeman for assistance with computational resources, supported by the Royal Society, for memory-intensive calculations. The research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Program (No. FP7/2007–2013)/ERC Grant Agreement No. 291522-3DIMAGE and the European Union’s Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2)
Recommended from our members
Impact of progressive global warming on the global-scale yield of maize and soybean
Global surface temperature is projected to warm over the coming decades, with regional differences expected in temperature change, rainfall and the frequency of extreme events. Temperature is a major determinant of crop growth and development, affecting planting date, growing season length and yield. We investigated the effects of increments of mean global temperature warming from 0.5 °C to 4 °C on soybean and maize development and yield, both globally and for the main producing countries, and simulated adaptation through changing planting date and variety. Increasing temperature resulted in reduced growing season lengths and ultimately reduced yields for both crops. The global yield for maize decreased as temperature increased, although the severity of the decrease was dependent on geographic region. Small temperature increases of 0.5 °C had no effect on soybean yield, although yield decreased as temperature increased. These negative effects, however, were partly compensated for by the implementation of adaptation strategies including planting earlier in the season and changing variety. The degree of compensation was dependent on geographical area and crop, with maize adaptation delaying the negative effects of temperature on yield, compared to soybean adaptation which increased yield in China, India and Korea DPR as well as delaying the effects in the remaining countries. The results of this paper indicate the degree to which farmer-controlled adaptation strategies can alleviate the negative impacts of increasing temperature on two major crop species
Commissioning of the BRIKEN beta-delayed neutron detector for the study of exotic neutron-rich nuclei
published_or_final_versio
THE BRIKEN PROJECT: EXTENSIVE MEASUREMENTS OF beta-DELAYED NEUTRON EMITTERS FOR THE ASTROPHYSICAL r PROCESS
An ambitious program to measure decay properties, primarily β-delayed
neutron emission probabilities and half-lives, for a significant number of
nuclei near or on the path of the rapid neutron capture process, has been
launched at the RIKEN Nishina Center. We give here an overview of the
status of the project