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The realisation of an opto-chemical ammonia sensor suitable for personal monitoring tasks is described, comprising a cyanine dye immobilised in a microporous glass thin film. The fabrication of sensor platforms incorporating embossed grating couplers provides a compact optical design with effective waveguiding characteristics, resulting in reversible ammonia sensitivity in the 5-100 ppm range in under 2 min. Cross-sensitivity of sensor response with water and other potential interferents is considered.  相似文献   
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Abstract

Energy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland.  相似文献   
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Doyle, Martin W., 2012. America’s Rivers and the American Experiment. Journal of the American Water Resources Association (JAWRA) 48(4): 820‐837. DOI: 10.1111/j.1752‐1688.2012.00652.x Abstract:  America’s rivers are managed, over long periods of time, based on the most basic ideologies of the United States (U.S.) government. An essential notion of the U.S. government, and thus a necessity of river management, is governing as experiment. This leads to three necessary characteristics of river management: (1) adapting management practices based on experience and thus creating management and agency structures that are highly malleable and that can change directions, (2) overlapping of management roles and responsibilities between agencies which includes intentional redundancy and interagency competition, and (3) federalism — the devolution of responsibilities between national, state, and other unit governments (e.g., municipalities, counties). While these characteristics are often criticized as inefficient, in fact they have provided a surprisingly effective system for river management that has responded to the needs of society at different times and in different places. A key question for river and water resource managers is whether this particular system, so initially unappealing, is best able to meet the future needs of the U.S.  相似文献   
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Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ2H values obtained from feathers showed that ≥25% of these APWRA‐killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ2H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental‐scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local‐scale renewable energy can have continental‐scale consequences.  相似文献   
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Doyle, Martin W. and F. Douglas Shields, 2012. Compensatory Mitigation for Streams Under the Clean Water Act: Reassessing Science and Redirecting Policy. Journal of the American Water Resources Association (JAWRA) 48(3): 494-509. DOI: 10.1111/j.1752-1688.2011.00631.x Abstract: Current stream restoration science is not adequate to assume high rates of success in recovering ecosystem functional integrity. The physical scale of most stream restoration projects is insufficient because watershed land use controls ambient water quality and hydrology, and land use surrounding many restoration projects at the time of their construction, or in the future, do not provide sufficient conditions for functional integrity recovery. Reach scale channel restoration or modification has limited benefits within the broader landscape context. Physical habitat variables are often the basis for indicating success, but are now increasingly seen as poor surrogates for actual biological function; the assumption “if you build it they will come” lacks support of empirical studies. If stream restoration is to play a continued role in compensatory mitigation under the United States Clean Water Act, then significant policy changes are needed to adapt to the limitations of restoration science and the social environment under which most projects are constructed. When used for compensatory mitigation, stream restoration should be held to effectiveness standards for actual and measurable physical, chemical, or biological functional improvement. To achieve improved mitigation results, greater flexibility may be required for the location and funding of restoration projects, the size of projects, and the restoration process itself.  相似文献   
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The multivoltine, estuarine amphipodGammarus lawrencianus has four generations per year in an environment where temperatures range seasonally from –1° to 25°C. Temperature-response curves for rates of brood production and development were determined by laboratory experiments and field observation. The life history and population dynamics were observed over a full annual cycle (1981) for a field population located at Rocky Run, Porter's Lake, Nova Scotia, Canada. On a natural (i.e., sidereal) time scale, the generations appear to have very different life histories: the two summer generations have short lives, rapid development and mature at small size (classicr-selection), whereas the overwintering generations have relatively low rates of mortality, slow development and mature at large size (classicK-selection). This pattern (larger size at maturity at lower temperatures) is widespread in aquatic poikilotherms. Similar life-history differences are evident among cohorts of the summer generations that mature at different temperatures. When time is expressed on a physiological scale that removes the effect of temperature on embryonic development and reproductive rate, the variation within and among generations is greatly reduced. In particular, an apparent alternation betweenr- andK-selection largely disappears. Because the generations are temporally isolated, it might be surmised that natural selection acting on the summer generations might antagonize the effects of natural selection acting on the fall and winter generations. However, the scaling of the rates of development, maturation, growth, reproduction and mortality on the physiological time scale derived from the temperature dependence of development and reproductive rate gives a very different and more homogeneous pattern.  相似文献   
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