Global hydrogen reservoirs in basement and basins

The authors are grateful to the Science and Technology Facilities Council (STFC) for funding, through Grant NE/G00322X/1. Samples were kindly contributed by K. Condie, M.J. Hole, and D. Muirhead. We are grateful to reviewers for their criticism.Peer reviewedPublisher PD

Hydrogen from Radiolysis of Aqueous Fluid Inclusions during Diagenesis

Acknowledgments We are grateful to J. Bowie and J. Still for skilled technical support and the staff at ICL-UK’s Boulby mine (especially Thomas Edwards), STFC’s Boulby underground Laboratory and the UK Centre for Astrobiology MINAR programme team (especially Sean Paling) for their support and supervised access to the site. The critical comments of two reviewers helped to improve the manuscript. Author Contributions John Parnell undertook the sampling. Nigel Blamey performed all analytical work. John Parnell wrote the manuscript.Peer reviewedPublisher PD

Reactivation of Limestone-Derived Sorbents using Hydration: Preliminary Results From a Fluidised Bed

A simple method of CO~2~ capture is by using the calcium looping cycle. The calcium looping cycle uses CaCO~3~ as a CO~2~ carrier, via the reversible reaction CaO(s) + CO~2~(g) = CaCO~3~(s), to extract CO2 from the exhaust stream and provide a pure stream of CO~2~ suitable for sequestration. 
A problem associated with the technology is that the capacity of the sorbent to absorb CO~2~ reduces significantly with the number of cycles of carbonation and calcination. The energy penalty of the cycle is considerably increased by cycling unreacted sorbent: hydration of unreactive sorbent has emerged as a promising strategy of reducing this penalty by regenerating the reactivity of exhausted sorbent.
A small atmospheric pressure fluidised bed reactor has been built and tested, that allows repeated cycling between two temperatures up to 1000 °C. 
Work presented here focuses on the effects of variation of the calcination temperature before hydration. Hydration has been found to more than double the reactivity of a spent sorbent cycled under the mildest conditions studied (calcination temperature of 840 °C). However, as calcination temperature is increased the observed reactivation decreases until little reactivation is observed for the sorbent cycled at 950 °C. The primary reason for this appears to be a substantial increase in friability of particles, with reactivity normalised for mass losses appearing similar independent of cycling temperature

Evidence for Seismogenic Hydrogen Gas, a Potential Microbial Energy Source on Earth and Mars

M thanks the STFC for a PhD studentship and the NASA Astrobiology Institute for additional funding (NNAI13AA90A; Foundations of Complex Life, Evolution, Preservation and Detection on Earth and Beyond). Alison Wright, Roger Gibson and Edward Lynch are thanked for contributing samples. We thank three anonymous reviewers for their insightful comments.Peer reviewedPostprin

Sampling methane in basalt on Earth and Mars

Peer reviewedPublisher PD

Improved tribology and materials for a new generation of hip prostheses

Not availabl

Bringing Down the Banhammer: Understanding the Impact of Competitive Players on Moderation Tactics in Overwatch

This thesis investigates how the need for player moderation tactics in Overwatch (Blizzard Entertainment, 2016) has shifted following the introduction of competitive and professional matches. With a player’s season rank heightening stakes when playing competitively, so too does the need to avoid toxic players impacting their win rates. Alongside this, the analysis of forums and developer updates examines what values (Flanagan and Nissenbaum, 2014) are embedded in the implemented moderation tactics, and players are responding to the tactics in community forums. This will provide a clearer insight on what data Blizzard developers are using to inform the design choices behind their moderation tactics

Mesoscale convective complexes over southern Africa

Includes bibliographical references.A combination of numerous factors, including geographic position, regional orography and local sea surface temperatures, ensures that subtropical southern Africa experiences considerable spatial and temporal variability in rainfall and is prone to both frequent flooding and drought events

Numerical simulation of a mesoscale convective system over the east coast of South Africa

Includes bibliographical references (leaves 189-200).Weather stations across the northern KwaZulu-Natal coastline recorded over 100 mm of rainfall over the 11112 February 2005, with Cape St. Lucia and Richards Bay measuring 111 mm and 96.8 mm, respectively. This heavy rainfall was associated with a mesoscale convective system (MCS) that initiated through small convective storms beginning early in the afternoon on 11 February 2005 and eventually decayed in the early morning hours on the 12th. The high-lying topography of the eastern escarpment and high diurnal surface heating possibly provided the trigger for the event. It was also identified that a combination of synoptic features in and around South Africa contributed to the evolution of the system. This particular MCS is investigated with a non-hydrostatic numerical model (MM5) to help determine which processes were important in its initiation and development, as well as what factors contributed to the associated heavy rainfall. The model is also used to conduct sensitivity tests to determine the role that local features, such as the regional topography and sea surface temperature, played in the evolution of the system. Through the various MM5 simulations, it was evident that the eastern escarpment played a key role in triggering the convective event, while it also had an influence on the low level winds that advected moisture into the region. A sea surface temperature sensitivity simulation highlighted the important role that the Agulhas Current plays in supplying moisture to fuel extreme precipitation events in South Africa. The significance of resolving large-scale features in the mid-latitudes in numerical simulations of weather events in South Africa was identified when excluding these features from the simulation. Through these simulations it was identified that the development of the MCS and the heavy nocturnal precipitation was due to a combination of the continuous moisture supply into the region, a conditionally unstable atmosphere, and uplift due to low level convergence and the local topography