Neutron powder-diffraction study of phase transitions in strontium-doped bismuth ferrite: 1. Variation with chemical composition.

We report results from a study of the crystal and magnetic structures of strontium-doped BiFeOusing neutron powder diffraction and the Rietveld method. Measurements were obtained over a wide range of temperatures from 300-800 K for compositions between 10%-16% replacement of bismuth by strontium. The results show a clear variation of the two main structural deformations-symmetry-breaking rotations of the FeOoctahedra and polar ionic displacements that give ferroelectricity-with chemical composition, but relatively little variation with temperature.

The design of a data management system at HEPS.

According to the estimated data rates, it is predicted that 24 PB raw experimental data will be produced per month from 14 beamlines at the first stage of the High-Energy Photon Source (HEPS) in China, and the volume of experimental data will be even greater with the completion of over 90 beamlines at the second stage in the future. To make sure that the huge amount of data collected at HEPS is accurate, available and accessible, an effective data management system (DMS) is crucial for deploying the IT systems. In this article, a DMS is designed for HEPS which is responsible for automating the organization, transfer, storage, distribution and sharing of the data produced from experiments.

Atomic pair distribution function research on LiMnO electrode structure evolution.

The mechanism research of structure-related reactions on LiMnO is important to enhance the electrochemical performance of lithium-manganese-rich layered oxides. Although there are some reports on the structure evolution of LiMnO during cycling process, the employed research techniques are very limited, mainly in/ex-situ X-ray diffraction, X-ray absorption and transmission electron microscopy. Here, atomic pair distribution function, a method to study the local atomic arrangement on the basis of average spectroscopic information, is used for the first time to study the local structure evolution of LiMnO during electrochemical charge/discharge cycles.