High voltage vanadium-metal hydride rechargeable semi-flow battery

We report a Vanadium-MH rechargeable semi-flow battery with an experimental OCV of 1.93 V and operating voltage of 1.70 V, very high values among rechargeable flow batteries with aqueous electrolytes. This hybrid battery consists of a graphite felt positive electrode operating in a mixed solution of 0.128 mol dm−3 VOSO4 and 2 mol dm−3 H2SO4, and a metal hydride negative electrode in 2 mol dm−3 KOH aqueous solution. The two electrolytes of different pH are separated by a bipolar membrane. The system demonstrated good reversibility and high efficiencies in coulomb (95%), energy (84%), and voltage (88%).postprin

Study of the electrochemical behavior of high voltage vanadium-metal hydride hybrid semi-flow battery

The Conference abstracts website is located at http://ma.ecsdl.org/content/by/yearSession - Redox Flow Batteries: Cell Characterization: abstract 2013 MA2013-01 481A vanadium-MH rechargeable semi-flow battery hybridizing the V4+/V5+ redox couple (positive) with the metal hydride (negative) was investigated. This battery has a higher cell voltage and the V(II)/V(III) redox couple is absent, hence avoiding the problems of V2+ oxidation. An experimental open circuit voltage of 1.86 V and an operating voltage of 1.65 V for this hybrid battery were obtained. These are very high values among all rechargeable flow batteries. The system demonstrated superior stability, reversibility, and efficiencies in coulomb (97%), energy (81.3%), and voltage (83.8%). © 2013 ECS - The Electrochemical Societypostprin

Viability of the health protection account in Hong Kong.

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Agreement between bioelectrical impedance and dual energy X-ray absorptiometry in assessing fat, lean and bone mass changes in adults after a lifestyle intervention

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Viral shedding, clinical history and transmission of influenza

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Viral evolution from one generation of human influenza infection to the next

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Methods for estimating the case fatality ratio for a novel, emerging infectious disease.

During the course of an epidemic of a potentially fatal disease, it is important that the case fatality ratio be well estimated. The authors propose a novel method for doing so based on the Kaplan-Meier survival procedure, jointly considering two outcomes (death and recovery), and evaluate its performance by using data from the 2003 epidemic of severe acute respiratory syndrome in Hong Kong, People's Republic of China. They compare this estimate obtained at various points in the epidemic with the case fatality ratio eventually observed; with two commonly quoted, naïve estimates derived from cumulative incidence and mortality statistics at single time points; and with estimates in which a parametric mixture model is used. They demonstrate the importance of patient characteristics regarding outcome by analyzing subgroups defined by age at admission to the hospital

Secondhand smoke exposure and maternal action to protect children from secondhand smoke: Pre- and post-smokefree legislation in Hong Kong

Background: Smokefree legislation may protect children from secondhand smoke (SHS) in the home from smoking parent(s). We examined the effect of the 2007 smokefree legislation on children's exposure to SHS in the home and maternal action to protect children from SHS exposure in Hong Kong. Methods: Families with a smoking father and a non-smoking mother were recruited from public clinics before (2005-2006, n = 333) and after the legislation (2007-2008, n = 742) which led to a major extension of smokefree places in Hong Kong. Main outcomes included children's SHS exposure in the home, nicotine level in mothers' and children's hair and home environment, mothers' action to protect children from SHS, and their support to the fathers to quit. Results: Fewer mothers post-legislation reported children's SHS exposure in the home (87.2% versus 29.3%, p<0.01), which was consistent with their hair nicotine levels (0.36ng/mg versus 0.04ng/mg, p<0.01). More mothers post-legislation in the last month took their children away from cigarette smoke (6.3% versus 92.2%; p<0.01) and advised fathers to quit over 3 times (8.3% versus 33.8%; p<0.01). No significant change was found in the content of smoking cessation advice and the proportion of mothers who took specific action to support the fathers to quit. Conclusions: SHS exposure in the home decreased and maternal action to protect children from SHS increased after the 2007 smokefree legislation. Maternal support to fathers to quit showed moderate improvement. Cessation services for smokers and specific interventions for smoking families should be expanded together with smokefree legislation. © 2014 Chan et al.published_or_final_versio

New anti-smoking legislation on second-hand smoke exposure of children in homes

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