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Thin Film Thermoelectric Metal–Organic Framework with High Seebeck Coefficient and Low Thermal Conductivity 下载免费PDF全文
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Cardenas LM Cuttle SP Crabtree B Hopkins A Shepherd A Scholefield D del Prado A 《The Science of the total environment》2011,409(6):1104-1115
As much as 60% of the nitrate in water in England is thought to derive from agriculture. Legislation aims to improve water quality by limiting nitrate concentration in surface and groundwaters to 50 mg l−1. The UK Government responded to the requirements of the EC Nitrate Directive by delineating Nitrate Vulnerable Zones (NVZs) to cover 55% of England in 2002 and increased it to 70% in 2009. In this study we assessed the cost-effectiveness of measures for implementation in livestock systems to mitigate nitrate leaching in the UK. These estimates were prepared for a range of hypothetical farms representative of typical dairy, beef and sheep farms at different locations in England and Wales and for a list of mitigation measures identified to reduce leaching. The NGAUGE and NFixCycle models were used to estimate leaching from these systems. The costs of implementation of the mitigation measures were also assessed in order to evaluate the cost-effectiveness of these measures. In general, the most effective measures to reduce leaching for all systems were the ones that involved a reduction in stocking rates and grazing time, followed by those involving improvements in fertiliser and crop management. Only in the case of the dairy system was effectiveness affected by location of the farm. The costs for implementation in the sheep system were relatively low compared with beef and dairy systems. Implementation of some of the measures with high cost-effectiveness would need to be incentivised financially or with legislation due to the high costs involved. 相似文献
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Faecal indicator organism concentrations and catchment export coefficients in the UK 总被引:2,自引:0,他引:2
Kay D Crowther J Stapleton CM Wyer MD Fewtrell L Anthony S Bradford M Edwards A Francis CA Hopkins M Kay C McDonald AT Watkins J Wilkinson J 《Water research》2008,42(10-11):2649-2661
Characterisation of faecal indicator organism (FIO) concentrations and export coefficients for catchments with particular combinations of land use and under specific climatic regimes is critical in developing models to predict daily loads and apportion sources of the microbial parameters used to regulate water quality. Accordingly, this paper presents a synthesis of FIO concentration and export coefficient data for the summer bathing season, with some comparative winter data, for 205 river/stream sampling points widely distributed across mainland UK. In terms of both geometric mean (GM) FIO concentrations and export coefficients (expressed as cfu km(-2) h(-1)), the results reveal (1) statistically significant elevations at high flow compared with base flow, with concentrations typically increasing by more than an order of magnitude and export coefficients by about two orders; (2) significantly higher values in summer than in winter under high-flow conditions; and (3) extremely wide variability between the catchments (e.g. four orders of magnitude range for GM faecal coliform concentrations), which closely reflects land use-with urban areas and improved pastures identified as key FIO sources. Generally, these two most polluting land uses are concentrated in lowland areas where runoff (m3 km(-2) h(-1)) is low compared with upland areas, which in the UK are dominated by rough grazing and forestry. Consequently, contrasts in export coefficients between land use types are less than for FIO concentrations. The GMs reported for most land use categories are based on 13 sites and exhibit quite narrow confidence intervals. They may therefore be applied with some confidence to other catchments in the UK and similar geographical regions elsewhere. Examples are presented to illustrate how the results can be used to estimate daily summer base- and high-flow FIO loads for catchments with different land use types, and to assess the likely effectiveness of certain strategies for reducing FIO pollutant loadings in areas with extensive areas of lowland improved pasture. 相似文献
5.
Benjamin W. B. Holman Damian Collins Ashleigh K. Kilgannon David L. Hopkins 《Journal of texture studies》2020,51(4):559-566
In this study, the relationship between sensory evaluation and several objective metrics of beef tenderness was tested. Objective metrics included shear force, sarcomere length, collagen content, myofibrillar, and sarcoplasmic protein solubility and particle size analysis. These results were compared to consumer panel scores of tenderness for the same aged beef striploin (longissimus lumborum muscle) samples. There was found to be a significant relationship between sarcomere length, shear force, and particle size with tenderness scores. Collagen content and protein solubilities were not associated to tenderness scores (p > 0.05). Sarcomere length contributions for explaining tenderness variation were overlapped by the contributions of shear force (collinearity). Independent models demonstrated that the lower 95% confidence interval of the fitted regression line exceeded 50% acceptance of tenderness when shear force values <42.6 N and when particle size values <198 μm. We can recommend these as thresholds for consumer acceptance of beef tenderness, although considerations of sample type, analytical methodology, and consumer demographics should be made prior to their adoption. This provision was based on the variation in tenderness scores evident between individual panelists and experimental striploins. 相似文献
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The paper deals with an experimental determination of the stretch zone dimensions in the notch tip in thin steel sheets. The stretch zone dimensions depend on steel grade, on the rolling direction as well as on the loading rate. Stretch zones were observed and measured on three steel grades. Fracture area and stretch zones were analysed by SEM. Stable crack growth was monitored by videoextensometry techniques on CT (Compact Tension) specimens. Specimens were loaded under two loading rates by eccentric tension, whereby the deformation in the notch surrounding area was recorded using a non-contact measurement–videoextensometry technique. Linear relation between the stretch zone dimensions was determined. 相似文献
8.
Ben Shneiderman Catherine Plaisant Rodrigo Botafogo Don Hopkins William Weiland 《New Review of Hypermedia and Multimedia》2013,19(2):101-117
Since browsing hypertext can present a formidable cognitive challenge, user interface design plays a major role in determining acceptability. In the Unix workstation version of Hyperties, a research-oriented prototype, we focussed on design features that facilitate browsing. We first give a general overview of Hyperties and its markup language. Customizable documents can be generated by the conditional text feature that enables dynamic and selective display of text and graphics. In addition we present: — an innovative solution to link identification: pop-out graphical buttons of arbitrary shape. — application of pie menus to permit low cognitive load actions that reduce the distraction of common actions, such as page turning or window selection. — multiple window selection strategies that reduce clutter and housekeeping effort. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and actions could be done rapidly, allowing users to concentrate on the contents. 相似文献
9.
Melis ArinPetra Lommens Nursen AvciSimon C. Hopkins Klaartje De BuysserIoannis M. Arabatzis Ioanna FasakiDirk Poelman Isabel Van Driessche 《Journal of the European Ceramic Society》2011,31(6):1067-1074
In this work, aqueous chemical solution deposition route suited for inkjet printing is used for the synthesis of photocatalytically active TiO2 coatings. Environmentally friendly precursor solutions with electromagnetic ink-jet printing, allows cheap and simple processing of TiO2 films on glass. The hydrolysis reaction of water sensitive titanium alkoxide (Ti-alkoxide) precursor is controlled by adding complexing agents as citric acid and triethanolamine prior to water addition, and aqueous stable solutions are achieved. The pH of the solutions is brought to neutral to guarantee flexible processing, avoid damage to substrates and equipment. Solution parameters are adapted to obtain optimal gelation conditions and good jettability. The influence of processing parameters on the phase formation and surface morphology is studied by thermogravimetric analysis and differential thermal analysis (TGA/DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The photocatalytic activity of the films is evaluated by the degradation of methyl orange. 相似文献
10.
Gerrit J. Knaap Lewis D. Hopkins 《Journal of the American Planning Association. American Planning Association》2013,79(3):314-326
In this article, we argue that insights can be gained by analyzing the use of urban growth boundaries (UGBs) for urban growth management as an inventory problem. The analysis provides three useful insights. First, it shows that where UGBs are employed, too much emphasis is placed on whether UGBs contain sufficient land to accommodate 20 years of growth and too little is placed on how frequently, how much, or under what circumstances UGBs should be expanded. Second, it shows that where market factors are used, they have been used inappropriately to increase the size of UGBs immediately after expansion, when they should be used to influence the size of UGBs immediately before expansion. Third, it shows that UGBs are likely to work better if expansions occur not after an arbitrary period of time, but when the supply—or the price—of land reaches some critical threshold. We conclude by asserting that the use of UGBs should not be governed by arbitrary rules of thumb, because such rules do not stand up to critical examination, they preclude adaptation to local situations, and they prevent experimentation. 相似文献