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The rapid rise in availability of large geospatial datasets for the development of hydrological models such as Soil and Water Assessment Tool (SWAT) has led to a dramatic increase in both the demand and availability of web services and tools that assist watershed modellers in incorporating data and knowledge into their modelling frameworks. Within the Canadian Great Lakes region, there is a huge potential for the application of SWAT in integrated water resources management. However, a potential barrier is the preparation of SWAT weather inputs that require time-intensive preprocessing of large data sets. Because such preprocessing is reproducible, the redundancy associated with it can be removed by introducing a web service that enables easy and open dissemination of climate data (including climate change and historical data) in SWAT-ready format. This short communication introduces such a web service called the Canadian Great Lakes Weather Data Service for SWAT (Can-GLWS). It hosts observed (historical) and projected (future) daily precipitation, daily maximum/minimum temperature, as well as weather generator database at regular grids (300 arc seconds or ~10 km) for use in SWAT simulations of the region. The novel Can-GLWS web service offers flexibility in selecting the region of interest by allowing them to be uploaded as a shapefile or to draw a rectangle or a polygon. We believe that such data as a service platform will help many practitioners to explore several issues pertaining to the sustainability of the freshwater resources of Canadian Great Lakes using the SWAT model.  相似文献   
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An experimental study has been carried out to determine the effect on the heat transfer and friction characteristics of an equilateral triangular solar air heater duct using inclined continuous ribs as roughness element on the absorber plate. The experimental study encompasses the range of Reynolds numbers from 5600 to 28,000, relative roughness height (e/Dh) 0.021–0.043, relative roughness pitch (p/e) 8–16 and angle of attack (α ) 30–60°. The duct has an aspect ratio (W/H) of 1.15. The effect of flow parameters and roughness parameters on heat transfer and friction factor is discussed. The thermohydraulic performance parameter has been determined for the given range of flow parameters and roughness parameters.  相似文献   
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BACKGROUND: Castor (Ricinus communis) seed cake (CSC), a byproduct of the vegetable‐oil industry, contains fairly good amounts of protein (crude protein, 290–390 g kg?1) which could be a suitable substitute of conventional oil cakes like soybean meal (SBM) in livestock diets but for the presence of a toxic glycoprotein, ricin. Efforts were, therefore, made to determine the feasibility of feeding CSC as such or after detoxification with lime (4%, wt/wt) by incorporating it into a total mixed ration (TMR) containing 65 and 35 parts ragi (Eleucine coracana) straw and concentrate mixture, respectively, with 11 g kg?1 CP and 50 g kg?1 TDN in which the SBM of a control diet was isonitrogenously replaced with either raw or lime‐treated CSC in test diets. The control and two test TMRs were fed to 24 sheep, respectively, divided at random into three dietary groups having equal number of animals for 150 days. RESULTS: Although lime treatment had a positive effect in reducing ricin by 58%, no adverse effect could be noticed by feeding raw or lime‐treated CSC in terms of body weight changes, macro‐ and micro‐nutrient utilisation, blood biochemical and mineral profile, rumen fermentation pattern, carcass traits, except the level of plasma immunoglobulins which was significantly (P < 0.05) higher in sheep fed CSC diets. No pathological lesions could be noticed in the tissues of visceral organs due to feeding the raw or treated CSC. CONCLUSIONS: The findings suggest no adverse effect in the nutritional performance of adult sheep due to feeding the raw or treated CSC when incorporated into TMRs, probably due to a dilution of the ricin concentration or the development of immunity to the glycoprotein ricin, warranting long‐term growth‐cum‐production studies. Copyright © 2008 Society of Chemical Industry  相似文献   
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利用聚合物前驱体陶瓷工艺制备了Si-Al-C-N陶瓷,并对陶瓷氧化和腐蚀特性进行了研究.结果表明掺入少量的Al将极大地提高Si-Al-C-N陶瓷的抗氧化和抗腐蚀能力.含1.4at%Al的Si-Al-C-N陶瓷的氧化速率较文献报道硅基材料的低10倍,并且在1200℃,50 h观察不到任何腐蚀.还讨论了Si-Al-C-N陶瓷的抗氧化与腐蚀的机理.  相似文献   
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This paper presents a theoretical analysis of the performance of a flat plate solar collector with the heat removal fluid undergoing a phase change. The resultant efficiency expression is a modified Hottel-Whillier-Bliss equation. Numerical computations are made to investigate the effect of vaporisation and operational parameters on the collector's performance. The collector's efficiency increases with the increase in liquid length until a point is reached when the region of superheating the vapour disappears. The efficiency is higher when a heat removal fluid of high latent heat of vaporisation is used in the collector. An increase in the saturation temperature of the working fluid (with increase of pressure) in the collector reduces its efficiency.  相似文献   
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