Grain coarsening behaviour of solution annealed Alloy 625 between 600–800°C

As with all alloys, the grain structure of the nickel-base superalloy 625 has a significant impact on its mechanical properties. Predictability of the grain structure evolution in this material is particularly pertinent because it is prone to inter-metallic precipitate formation both during manufacture and long term or high temperature service. To this end, analysis has been performed on the grain structure of Alloy 625 aged isothermally at temperatures between 600 and 800 °C for times up to 3000 h. Fits made according to the classical Arrhenius equation describing normal grain growth yield an average value for the activation energy of a somewhat inhomogeneous grain structure above 700 °C of 108.3±6.6 kJ mol−1 and 46.6±12.2 kJ mol−1 below 650 °C. Linear extrapolation between 650 and 700 °C produces a significantly higher value of 527.7±23.1 kJ mol−1. This result is ultimately a consequence of a high driving force, solute-impeded grain boundary migration process operating within the alloy. Comparison of the high and low temperature values with the activation energy for volume self-diffusion and grain boundary diffusion identifies the latter as the principle governing mechanism for grain growth in both instances. A decrease in the value of the time exponent (n) at higher temperatures despite a reduction in solute drag is attributable to the Zener pinning imposed by grain boundary M6C and M23C6 particles identified from Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray Spectroscopy (EDXS) analysis. Vickers hardness results show the dominance of intermetallic intragranular precipitates in the governance of the mechanical properties of the material with grain coarsening being accompanied by a significant increase in hardness. Furthermore, the lack of any correlation with grain growth behaviour indicates these phases have no significant effect on the grain evolution of the material

The impact of COVID-19 critical illness on new disability, functional outcomes and return to work at 6 months: a prospective cohort study

Background: There are few reports of new functional impairment following critical illness from COVID-19. We aimed to describe the incidence of death or new disability, functional impairment and changes in health-related quality of life of patients after COVID-19 critical illness at 6 months. Methods: In a nationally representative, multicenter, prospective cohort study of COVID-19 critical illness, we determined the prevalence of death or new disability at 6 months, the primary outcome. We measured mortality, new disability and return to work with changes in the World Health Organization Disability Assessment Schedule 2.0 12L (WHODAS) and health status with the EQ5D-5LTM. Results: Of 274 eligible patients, 212 were enrolled from 30 hospitals. The median age was 61 (51–70) years, and 124 (58.5%) patients were male. At 6 months, 43/160 (26.9%) patients died and 42/108 (38.9%) responding survivors reported new disability. Compared to pre-illness, the WHODAS percentage score worsened (mean difference (MD), 10.40% [95% CI 7.06–13.77]; p < 0.001). Thirteen (11.4%) survivors had not returned to work due to poor health. There was a decrease in the EQ-5D-5LTM utility score (MD, − 0.19 [− 0.28 to − 0.10]; p < 0.001). At 6 months, 82 of 115 (71.3%) patients reported persistent symptoms. The independent predictors of death or new disability were higher severity of illness and increased frailty. Conclusions: At six months after COVID-19 critical illness, death and new disability was substantial. Over a third of survivors had new disability, which was widespread across all areas of functioning.Carol L. Hodgson, Alisa M. Higgins, Michael J. Bailey, Anne M. Mather, Lisa Beach, Rinaldo Bellomo, Bernie Bissett, Ianthe J. Boden, Scott Bradley, Aidan Burrell, D. James Cooper, Bentley J. Fulcher, Kimberley J. Haines, Jack Hopkins, Alice Y. M. Jones, Stuart Lane, Drew Lawrence, Lisa van der Lee, Jennifer Liacos, Natalie J. Linke, Lonni Marques Gomes, Marc Nickels, George Ntoumenopoulos, Paul S. Myles, Shane Patman, Michelle Paton, Gemma Pound, Sumeet Rai, Alana Rix, Thomas C. Rollinson, Janani Sivasuthan, Claire J. Tipping, Peter Thomas, Tony Trapani, Andrew A. Udy, Christina Whitehead, Isabelle T. Hodgson, Shannah Anderson, Ary Serpa Neto, and The COVID-Recovery Study Investigators and the ANZICS Clinical Trials Grou

Report to NERC : InformaTec Soils : report for the InformaTec-Soils meeting at Defra, Nobel House, March 14th 2011

InformaTec is a 2-year, NERC-funded project that seeks to identify how to manage the increasing wealth of environmental data and information so that it can be transmitted, distributed, stored, archived, analysed and visualised, and in so doing, aims to recognise and develop opportunities for knowledge and technology transfer, both nationally and internationally. As such, InformaTec addresses a major objective of the NERC science strategy, namely, the “exploitation of technological advances to develop improved methods of monitoring environmental change.” InformaTec-Soils is one component of InformaTec; other aspects of the project focus on environmental monitoring, data standards, interoperability, and distributed computing. The specific aim of InformaTec-Soils is to draw together key players having interest in the collection and synthesis of large-scale soil data sets with a view to identifying what needs to be done to improve understanding of soil and environmental change. As part of the InformaTec-Soils initiative, a meeting of 24 experts from across the UK was convened at Defra, in London, on 14 March 2011. Through presentations, roundtable discussions and breakout groups, the meeting explored, current informatics, methodological and cultural challenges, and constraints, to the synthesis of UK and European soils data for understanding soil and environmental change. This report presents a vision for an ecosystems approach to soils and summarizes the conclusions and recommendations of the meeting held in London. As well as identifying opportunities for the soils community generally, the report will be presented to NERC to inform decisions on future funding. The authors of the report extend their gratitude to all who contributed to the meeting and the production of this report. The report identifies the following important research topics for soils: Key areas for research: 1) Framework development. 2) Quantifying the soil resource, stocks, fluxes, transformations and identifying indicators. 3) Valuing the soil resource for its ecosystem services and natural capital. 4) Developing management strategies and decision support tools. Within these 4 key areas for research we identify the following 5 major challenges that the NERC technologies theme should address: Major research challenges: 1. Ecosystem approach to national soil monitoring; how we measure and model at a range of scales. 2. Exploit new technologies for airborne, ground based sensor networks, and molecular biology techniques to link from structure through to function and on to service. 3. Develop data accessibility (via cloud), and integration by exploiting new data IT tools (eg Open MI) to support projects building exemplar or baseline data/models eg EVOp project (Community). 4. Decision support tools, simple, practical tools for people trying to utilize and visualise data for a range of common purposes (e.g. planning). 5. Pathways to ‘valuation’. How do you link users perceptions of value to the parameters created by the data and models? (e.g developing techniques from social–science research in terms of perceptions and value judgements). Some of the challenges and opportunities to arise from the meeting with regard to ‘Data Handling’ and ‘Measurement Methods and Technologies’ are identified in two appendices to the report

Selective anchoring groups for molecular electronic junctions with ITO electrodes

Indium tin oxide (ITO) is an attractive substrate for single-molecule electronics since it is transparent while maintaining electrical conductivity. Although it has been used before as a contacting electrode in single-molecule electrical studies, these studies have been limited to the use of carboxylic acid terminal groups for binding molecular wires to the ITO substrates. There is thus the need to investigate other anchoring groups with potential for binding effectively to ITO. With this aim, we have investigated the single-molecule conductance of a series of eight tolane or “tolane-like” molecular wires with a variety of surface binding groups. We first used gold-molecule- gold junctions to identify promising targets for ITO selectivity. We then assessed the propensity and selectivity of carboxylic acid, cyanoacrylic acid, and pyridinium-squarate to bind to ITO and promote the formation of molecular heterojunctions. We found that pyridinium squarate zwitterions display excellent selectivity for binding to ITO over gold surfaces, with contact resistivity comparable to that of carboxylic acids. These single-molecule experiments are complemented by surface chemical characterization with X-ray photoelectron spectroscopy, quartz crystal microbalance, contact angle determination, and nanolithography using an atomic force miscroscope. Finally, we report the first density-functional theory calculations involving ITO electrodes to model charge transport through ITO-molecule-gold heterojunctions