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131.
While much work has been invested in addressing the economic and technical basis of disaster preparedness, less effort has been directed towards understanding the cultural and social obstacles to and opportunities for disaster risk reduction. This paper presents local insights from five different national settings into the cultural and social contexts of disaster preparedness. In most cases, an early warning system was in place, but it failed to alert people to diverse environmental shocks. The research findings show that despite geographical and typological differences in these locations, the limitations of the systems were fairly similar. In Kenya, people received warnings, but from contradictory systems, whereas in the Philippines and on the island of Saipan, people did not understand the messages or take them seriously. In Bangladesh and Nepal, however, a deeper cultural and religious reasoning serves to explain disasters, and how to prevent them or find safety when they strike.  相似文献   
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Journal of Polymers and the Environment - Agri-food waste and by-products are being increasingly revalued, exploiting their potential. One of the attractive alternatives is their use as raw...  相似文献   
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Environmental Chemistry Letters - The recent rise of red tide harmful algal blooms has induced ecosystem degradation, economic losses, and aquaculture damage, yet little is known on prevention and...  相似文献   
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Over the last decade, suppliers of drinking water have recognised the limitations of relying solely on end-product monitoring to ensure safe water quality and have sought to reinforce their approach by adopting preventative strategies where risks are proactively identified, assessed and managed. This is leading to the development of water safety plans; structured 'route maps' for managing risks to water supply, from catchment to consumer taps. This paper reviews the Hazard Analysis and Critical Control Point (HACCP) procedure on which many water safety plans are based and considers its appropriateness in the context of drinking water risk management. We examine water safety plans in a broad context, looking at a variety of monitoring, optimisation and risk management initiatives that can be taken to improve drinking water safety. These are cross-compared using a simple framework that facilitates an integrated approach to water safety. Finally, we look at how risk management practices are being integrated across water companies and how this is likely to affect the future development of water safety plans.  相似文献   
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High voltage power lines are known to produce corona ions that can be carried from the line by the wind, progressively attaching to ambient aerosol particles and causing fluctuations in the Earth’s atmospheric potential gradient. A fixed site monitoring station was installed near two power lines, which recorded the potential gradient at 1 s intervals and the ambient weather conditions every 10 min. The station ran continuously from January 2007 to December 2008, accumulating long-term data. Results from 2008 show an increase in potential gradient variability when a wind is blowing across the power lines towards the station, indicating that corona ions may be present in this environment.  相似文献   
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Sixty five samples were taken with a Transition Flow Reactor (TFR) for the measurement of nitric acid (HNO3) and nitrate particulates (NO 3 ), in a central Athens street having a heavy traffic density, between February 1989 and February 1990. It was established that the TFR theory overestimated HNO3 and underestimated NO 3 . This is caused by the retention of a fraction of the NO2 and a fraction of the HNO2 as NO 2 on the sampler's nylon linear. NO 2 is in turn oxidized to NO 3 and this is determined as HNO3. Two modifications of the TFR theory are proposed for a better estimation of the HNO3 and NO 3 . With the first modification HNO3 is estimated as being equal to the smaller of two values: HNO3 TFR and the value calculated if it is considered that 91% of HNO3 is retained by the nylon filter. The second modification was based on the quantification of the effect of NO2 on the concentrations of HNO3 and NO 3 . This modification is an improvement on the first one and enables the calculation of a lower limit for the concentration of HNO2. Both modifications improve the accuracy of the TFR sampler in measuring HNO3 and NO 3 , without altering it structurally. It was also found that the nylon filter partially retains some NH3, causing a negative error in the measurement of NH 4 + with the TFR. The extent of NH3 retention on the nylon filter is proportional to the HNO3 concentration. This error must be taken into account whenever NH 4 + is being determined.  相似文献   
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