Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined with single cell battery RFB tests on selected redox pairs. Data shows that both the solubility and redox potential are determined by the position of the side groups and only to a small extent by the number of side groups. Additionally, the chemical stability and possible degradation mechanisms leading to capacity loss over time are discussed. The main challenge for the development of all-organic RFBs is to identify a redox pair for the positive side with sufficiently high stability and redox potential that enables battery cell potentials above 1 V

Two Legionnaires' disease cases associated with industrial waste water treatment plants: a case report

<p>Abstract</p> <p>Background</p> <p>Finnish and Swedish waste water systems used by the forest industry were found to be exceptionally heavily contaminated with legionellae in 2005.</p> <p>Case presentation</p> <p>We report two cases of severe pneumonia in employees working at two separate mills in Finland in 2006. <it>Legionella </it>serological and urinary antigen tests were used to diagnose Legionnaires' disease in the symptomatic employees, who had worked at, or close to, waste water treatment plants. Since the findings indicated a <it>Legionella </it>infection, the waste water and home water systems were studied in more detail. The antibody response and <it>Legionella </it>urinary antigen finding of Case A indicated that the infection had been caused by <it>Legionella pneumophila </it>serogroup 1. Case A had been exposed to legionellae while installing a pump into a post-clarification basin at the waste water treatment plant of mill A. Both the water and sludge in the basin contained high concentrations of <it>Legionella pneumophila </it>serogroup 1, in addition to serogroups 3 and 13. Case B was working 200 meters downwind from a waste water treatment plant, which had an active sludge basin and cooling towers. The antibody response indicated that his disease was due to <it>Legionella pneumophila </it>serogroup 2. The cooling tower was the only site at the waste water treatment plant yielding that serogroup, though water in the active sludge basin yielded abundant growth of <it>Legionella pneumophila </it>serogroup 5 and <it>Legionella rubrilucens</it>. Both workers recovered from the disease.</p> <p>Conclusion</p> <p>These are the first reported cases of Legionnaires' disease in Finland associated with industrial waste water systems.</p

Developing numeracy in the Workplace

Internationally, adult literacy and numeracy are in general recognized as cultural techniques. However, the meaning of the two competences and the means of their development are contested among politicians, education bureaucrats, and researchers. Numeracy is often subsumed under literacy and/or described in isolation from the situational context. Adult numeracy at work is often described unproblematically as the transfer of mathematical knowledges and skills from school to workplace. With reference to Bernstein’s theoretical framework, we claim that adult numeracy in the labour market is a horizontal discourse, in contrast to the vertical discourse of mathematics. This article draws on the findings from an Australian study of numeracy in the context of chemical spraying and handling, utilising a methodology based on activity theory. The main findings are that mathematically straightforward skills become transformed into workplace numeracy competence, when the complexities associated with successful task completion as well as the supportive role of mediating artefacts and the workplace community of practice are taken into account