Transport and Association of Ions in Lithium Battery Electrolytes Based on Glycol Ether Mixed with Halogen-Free Orthoborate Ionic Liquid

© 2017 The Author(s). Ion transport behaviour of halogen-free hybrid electrolytes for lithium-ion batteries based on phosphonium bis(salicylato)borate [P 4,4,4,8 ][BScB] ionic liquid mixed with diethylene glycol dibutyl ether (DEGDBE) is investigated. The Li[BScB] salt is dissolved at different concentrations in the range from 0.15 mol kg -1 to 1.0 mol kg -1 in a mixture of [P 4,4,4,8 ][BScB] and DEGDBE in 1:5 molar ratio. The ion transport properties of the resulting electrolytes are investigated using viscosity, electrical impedance spectroscopy and pulsed-Field Gradient (PFG) NMR. The apparent transfer numbers of ions are calculated from the diffusion coefficients measured by using PFG NMR. PFG NMR data suggested ion association upon addition of Li salt to the [P 4,4,4,8 ][BScB] in DEGDBE solution. This is further confirmed by liquid state 7 Li and 11 B NMR, and FTIR spectroscopic techniques, which suggest strong interactions between the lithium cation and oxygen atoms of the [BScB] - anion in the hybrid electrolytes

EFFECT OF HEAT TREATMENTS ON THE TENSILE PROPERTIES OF ADDITIVELY MANUFACTURED 15-5 PH STAINLESS STEEL

This study investigated the effect of post-manufacture heat treatments on the microstructure and mechanical properties of 15-5 PH stainless steel (SS) fabricated by laser powder-directed energy deposition (LPDED). Various heat treatment procedures (CA-H900 and CA-H1150) were conducted to evaluate their effects on the tensile behavior of LP-DED 15-5 PH SS. Scanning electron microscopy was used to characterize the microstructural features and the fracture surfaces. Tensile tests were performed to evaluate the mechanical properties at cryogenic and room temperatures. The mechanical behavior of the LP-DED 15-5 PH SS in different heat treatment conditions is discussed based on their microstructures and fracture surfaces. Reduction in area of CA-H1150 treated specimens after tensile tests was significantly higher than CA-H900 ones, while the ultimate tensile and yield strengths of CA-H900 specimens were higher compared to the CA-H1150 ones. The CA-H1150 specimens had relatively coarser Cu-enriched precipitates, and exhibited greater necking compared to CA-H900 specimens.Mechanical Engineerin

THE INFLUENCE OF HEAT TREATMENTS ON THE MICROSTRUCTURE AND TENSILE PROPERTIES OF ADDITIVELY MANUFACTURED INCONEL 939

This study investigated the effect of heat treatment variations on the microstructure and tensile properties of laser powder bed fused Inconel 939. Three different heat treatment schedules, all of which comprise stress relief, hot isostatic pressing, solution annealing, and aging, were followed, and resulting changes in microstructure were analyzed using scanning electron microscopy. Tensile tests were conducted on specimens subjected to different heat treatments to evaluate the mechanical properties at room temperature. Microstructural results showed that solution treatment at 1190 °C for 4 h led to better removal of dendritic microstructure, while second-step aging at 850 °C resulted in monomodal distribution of precipitates. However, the second-step aging temperatures from 750 to 800 °C resulted in bi-modal distribution. The optimal heat treatment schedule, which yielded a superior combination of strength and ductility, involved solution treatment at 1190 °C for 4 h and two-step aging at 1000 °C for 6 h and 800 °C for 4 h.Mechanical Engineerin

The impacts of climate change on the winter water cycle of the western Himalaya

Some 180 million people depend on the Indus River as a key water resource, fed largely by precipitation falling over the western Himalaya. However, the projected response of western Himalayan precipitation to climate change is currently not well constrained: CMIP5 GCMs project a reduced frequency and vorticity of synoptic-scale systems impacting the area, but such systems would exist in a considerably moister atmosphere. In this study, a convection-permitting (4 km horizontal resolution) setup of the Weather Research and Forecasting (WRF) model is used to examine 40 cases of these synoptic-scale systems, known as western disturbances (WDs), as they interact with the western Himalaya. In addition to a present-day control run, three experiments are performed by perturbing the boundary and initial conditions to reflect pre-industrial, RCP4.5 and RCP8.5 background climates respectively. It is found that in spite of the weakening intensity of WDs, net precipitation associated with them in future climate scenarios increases significantly; conversely there is no net change in precipitation between the pre-industrial and control experiments despite a significant conversion of snowfall in the pre-industrial experiment to rainfall in the control experiment, consistent with the changes seen in historical observations. This shift from snowfall to rainfall has profound consequences on water resource management in the Indus Valley, where irrigation is dependent on spring meltwater. Flux decomposition shows that the increase in future precipitation follows directly from the projected moistening of the tropical atmosphere (which increases the moisture flux incident on the western Himalaya by 28%) overpowering the weakened dynamics (which decreases it by 20%). Changes to extreme rainfall events are also examined: it is found that such events may increase significantly in frequency in both future scenarios examined. Two-hour maxima rainfall events that currently occur in 1-in-8 WDs are projected to increase tenfold in frequency in the RCP8.5 scenario; more prolonged (one-week maxima) events are projected to increase fiftyfold

Turtle Island’s Little People: Indigenous Oral Traditions

Western societies view borders as absolutes. And while these human-made dividers do have some benefits, the restriction of people to specific geographical areas that are often seen to be exceedingly arbitrary does more than just prevent the migration of peoples. When we stop humans, we also stop their ideas, cultures, technologies and stories. Across Turtle Island there over 590 tribes, but historically open boarders and communities make connections and transfer of ideas and information -as well as the people who share them- much easier. Indigenous tribes have geographical limits, but these are fluid, and make considerations for a variety of factors. By looking at stories of Little People we can see how these boarders functioned. These stories have many similarities, but are each unique to the community or group they belong to. In conjunction with my oral presentation I will show a map of these stories using ARCGIS software and show traditional tribal areas in comparison with each tribes little people story and how these are shared through the open boundary lines of these communities that have geographic proximity. Indigenous groups still have borders, but their open nature allows for information (such as these oral traditions) to spread between groups and be used and adapted by all. Exploring these stories not only keeps them alive for future generations, but can tell us much about who wrote them and what caused their creations, but also about how these ideas are spread and why. Little People are small but important figures in indigenous cultures, and their proliferation across Turtle Island speaks largely to shared experiences, thoughts and fears across large and potentially dissimilar groups of people. However, these stories are due to the structuring of indigenous communities and the borders that surround them, and point to solutions to the current issues with modern borders by opening them and creating fluidity for both the borders themselves and the people they contain