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In the pursuit to develop practical sodium-ion batteries, safe negative insertion (anode) materials are essential. Recently, Na2Ti6O13 has been unveiled by conventional solid-state synthesis as a 0.85 V anode with 1-dimensional Na+ diffusion pathways. Here, an energy-savvy autocombustion synthesis has been successfully implemented to produce the target compound Na2Ti6O13 by restricting the annealing duration within 2 h. This drastic reduction in heat-treatment time involves minimal grain-growth hence forming homogeneous nanostructured particles (~100 nm). It benchmarks the shortest synthesis of Ti-based anodes for sodium-ion batteries. The current work describes various aspects of autocombustion route. The as-prepared compound delivers near theoretical capacity (ca. 40 mAh g-1) involving a Ti4+/Ti3+ redox potential centered at 0.83 V (vs. Na/Na+) with excellent reversibility. Using both experiment and bond valence site energy (BVSE) modeling, the electrochemical, Na+ diffusion pathways and corresponding energy barriers have been explained. [ABSTRACT FROM AUTHOR]

Electron monitor unit (MU) calculation requires measured beam data such as the relative output factor (ROF) of a cone, insert correction factor (ICF) and effective source-to-surface distance (ESD). Measuring the beam data to cover all possible clinical cases is not practical for a busy clinic because it takes tremendous time and labor. In this study, we propose a practical approach to reduce the number of data measurements without affecting accuracy. It is based on two findings of dosimetric properties of electron beams. One is that the output ratio of two inserts is independent of the cone used, and the other is that ESD is a function of field size but independent of cone and jaw opening. For the measurements to prove the findings, a parallel plate ion chamber (Markus, PTW 23343) with an electrometer (Cardinal Health 35040) was used. We measured the outputs to determine ROF, ICF and ESD of different energies (5-21 MeV). Measurements were made in a Plastic Water phantom or in water. Three linear accelerators were used: Siemens MD2 (S/N 2689), Siemens Primus (S/N 3305) and Varian Clinic 21-EX (S/N 1495). With these findings, the number of data set to be measured can be reduced to less than 20% of the data points.