StructuralandelectronicpropertiesofLi-ionbatterycathodematerial MoF3 from first-principles

通讯作者地址: Zhu, ZZThe transition metal fluorides have been extensively investigated recently as the electrode materials with high working voltage and large capacity. The structural, electronic and magnetic properties of MoF3 are studied by the first-principles calculations within both the generalized gradient approximation (GGA) and GGA-I-U frameworks. Our results show that the antiferromagnetic configuration of MoF3 is more stable than the ferromagnetic one, which is consistent with experimental results. The analysis of the electronic density of states shows that MoF3 is a Mott-Hubbard insulator with a d-d type band gap, which is similar to the case of FeF3. Moreover, small spin polarizations were found on the sites of fluorine ions, which accords with a fluorine-mediated superexchange mechanism for the Mo-Mo magnetic interaction.National Natural Science Foundation of China 21233004 Scientific Research Foundation of Fujian Provincial Education Department JK201104

Implementing Standardization Education at the National Level

This paper explores how standardization education can be implemented at the national level. Previous studies form the main source for the paper. This research shows that implementation of standardization in the national education system requires policy at the national level, a long term investment in support, and cooperation between industry, standardization bodies, academia, other institutions involved in education, and government. The approach should combine bottom-up and top-down. The paper is new in combining previous findings to an underpinned recommendation on how to implement standardization education

The Alpha Magnetic Spectrometer (AMS) on the international space station: Part II — Results from the first seven years

The Alpha Magnetic Spectrometer (AMS) is a precision particle physics detector on the International Space Station (ISS) conducting a unique, long-duration mission of fundamental physics research in space. The physics objectives include the precise studies of the origin of dark matter, antimatter, and cosmic rays as well as the exploration of new phenomena. Following a 16-year period of construction and testing, and a precursor flight on the Space Shuttle, AMS was installed on the ISS on May 19, 2011. In this report we present results based on 120 billion charged cosmic ray events up to multi-TeV energies. This includes the fluxes of positrons, electrons, antiprotons, protons, and nuclei. These results provide unexpected information, which cannot be explained by the current theoretical models. The accuracy and characteristics of the data, simultaneously from many different types of cosmic rays, provide unique input to the understanding of origins, acceleration, and propagation of cosmic rays.</p