Search

This work aimed to design a facile preparation of sandwich-liked Ge nanoparticles/nitrogen-doped reduced graphene oxide (Ge/NrGO) nanocomposites used as anode in lithium-ion batteries through the chemical solution route. The advanced electron microscopy, STEM-HAADF and STEM-EDS mapping, evidenced that the individual Ge particles with sizes ranging from 5 to 20 nm were distributed and wrapped as sandwiches within the multi-layered NrGO sheets, which were mainly composed of the pyridinic-N form (4.8%wt.). The battery performances of the 20Ge/NrGO nanocomposite anode exhibit a high reversible capacity (700 mAh g−1) and retained its outstanding stability during long-term cycling. The internal resistance (28.0 Ω) was also decreased after cycling, according to EIS measurement. The sandwiched structure of Ge-based nanocomposite with the interconnected NrGO layers discussed in this article possessed the high-performance LIBs with great potential application in energy storage technologies.

The 6063 aluminum billet alloy has been widely used as raw materials for aluminum extrusion profiles. A high-quality billet for good extrusion products is provided from a heat treatment process called homogenization. This process can give a homogeneous microstructure by reducing microsegregation and dissolving intermetallic phases. However, homogenization can create a very large grain size (abnormal grains) in 6063 aluminum billets. Fe content is one of the main factors that is strongly related to abnormal grain growth because Fe can form Fe-containing intermetallic phases in 6063 aluminum structure. The morphology and volume fraction of Fe-containing intermetallic phases are subjected to change during homogenization. These results relate to a decrease in the volume fraction of intermetallics, which corresponds to the Zener pinning pressure, grain boundary migration, and abnormal grain growth. Therefore, this study aims to understand the evolution of Fe-containing intermetallic phases on abnormal grain growth in 6063 aluminum billets during homogenization. Ex-situ characterization by energy dispersive spectrometer (EDS) and electron backscattered diffraction (EBSD) was performed on 6063 aluminum alloy to gain an in-depth understanding of abnormal grain growth. Keywords: 6063 aluminum alloy, Abnormal grain growth, Homogenization, Ex-situ characterization, Zener pinning

In 2007, the World Health Organization, together with United Nations and international organization as well as experts, met to draw upon existing evidence and practical experience from regions, countries and individual schools in promoting health through schools. The goal of the meeting was to identify current and emerging global factors affecting schools, and to help them respond more effectively to health, education and development opportunities. At the meeting, a Statement was developed describing effective approaches and strategies that can be adopted by schools to promote health, education and development. Five key challenges were identified. These described the need to continue building evidence and capturing practical experience in school health; the importance of improving implementation processes to ensure optimal transfer of evidence into practice; the need to alleviating social and economic disadvantage in access to and successful completion of school education; the opportunity to harness media influences for positive benefit, and the continuing challenge to improve partnerships among different sectors and organizations. The participants also identified a range of actions needed to respond to these challenges, highlighting the need for action by local school communities, governments and international organizations to invest in quality education, and to increase participation of children and young people in school education. This paper describes the rationale for and process of the meeting and the development of the Statement and outlines some of the most immediate efforts made to implement the actions identified in the Statement. It also suggests further joint actions required for the implementation of the Statement.