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91.
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Simulation of a localized heating system for broiler brooding to improve energy performance 下载免费PDF全文
The aim of this work is to evaluate the performance of an innovative localized solar‐assisted pen heating system for brooding using a 3D computational simulation model of the heated space. The warm air‐curtained pen ensures acceptable temperature, air velocity, relative humidity, and air quality that meet the ventilation and heat requirements for a typical pen of 100 chicks as recommended by the American Society of Heating Refrigeration and Air Conditioning Engineers and American Society of Agricultural and Biological Engineers. The supply flow characteristics and the simulated velocity and temperature field of the curtained region were determined such that they meet the ventilation requirements and comfort criteria. Results show that air supplied at 40°C is capable of delivering the desired microenvironment at bird level while the heat input to the unit is 685 W when outdoor temperature is ?5°C. The system's energy performance was then analyzed using a prototype of 16 pens. The energy consumption of the new heating scheme consumed one third of the energy required by conventional non‐localized system. Moreover, integrating the new design with a solar system utilizing parabolic concentrators provided 72% of the power load from solar energy during a winter flock operation and 100% during other seasons. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
93.
将含有电活性物质的离子选择性膜直接滴涂在玻碳电极上,制成一种新型伏安型离子选择性电极(VISE)。通过在电极上施加循环伏安信号,提取电活性物质的还原峰电位可实现待测离子的定量分析。将这种VISE应用于pH检测,分别考察VISE的pH响应特性、离子选择性、实际样检测能力以及对积累电荷的抗干扰能力。结果表明:基于循环伏安法的VISE在pH检测中具有较好的准确性、灵敏度、重复性和离子选择性,可用于实际样品的检测。相比于基于电位分析法的传统离子选择性电极(ISE),可不受电荷积累的影响,在水质的实时在线监测中具有较好的应用前景。 相似文献
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Zinc tungstate–carbon nanoparticles were synthesized by a one-step hydrothermal process followed by heat treatment. X-ray diffraction results indicated that the addition of glucose prevented grain growth of zinc tungstate during the hydrothermal process and subsequent heat treatment. Transmission electron microscopy images showed that the zinc tungstate nanoparticles were coated by carbon with a thickness of 1 nm following heat treatment at 550°C and a diameter of 10 nm with a homogeneous morphology. Electrochemical measurements showed that the zinc tungstate–carbon nanoparticles reached an initial discharge capacity of 990 mAh g?1 at a current density of 50 mA. g?1. The specific capacity of the zinc tungstate-carbon nanoparticles was maintained at approximately 400 mAh g?1 after 50 cycles, exhibiting better stability than pure zinc tungstate due to the carbon coating providing high conductivity with the zinc tungstate nanoparticle. 相似文献
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This paper summarizes the results of testing on salts of organic acids for evaluating their use as inhibitors of rebar corrosion in chloride‐contaminated concrete. Initially a screening based on electrochemical tests in alkalinized calcium hydroxide solutions was performed on a number of carboxylic acid salts with different number of carbon atoms in the chain and carboxylic groups, also covering substances with hydroxyl and amine group substituents. The screening was completed by testing on carbon steel rebars in concretes with chlorides and substances added at 1:1 molar ratio, focused on sodium lactate, sodium oxalate and sodium borate for comparison. The monitoring of free corrosion potential and linear polarization resistance of steel bars have confirmed significant inhibition only for lactate. Corrosion was only restricted to occluded zones where the access of substance was limited by disadvantageous geometry, producing shallow attacks. Results of further tests in saturated calcium hydroxide solution are reported in order to assess the inhibition ability of lactate as a function of its content, chloride content and pH. 相似文献
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The corrosion behaviour of martensitic stainless injection‐pipeline steel X46Cr13 exposed to CO2 saturated artificial saline brine with high chloride concentration similar to onshore CCS‐site at Ketzin, Germany has been investigated by means of electrochemical technique and microscopic observations at short exposure times (up to 24 h) and by mass loss and metallographic observations at exposure times up to 17520 h. Pitting corrosion kinetics has been characterised and the predictions about the corrosion mechanism are made. 相似文献
100.
Dye-sensitized solar cells (DSSCs) based on disulfide/thiolate (T2/T−) redox couples have attracted remarkable attention due to their high efficiency and low cost. As an indispensible part of DSSCs, counter electrode (CE) design plays a crucial role in high efficiency DSSCs. This mini-review paper selectively reviews the recent advances in T-mediated DSSCs using novel CE (namely cathode) materials, mainly including noble metal platinum (Pt), carbon materials, transition metal compounds (TMCs), polymers, and hybrids, thus highlighting the merits and demerits of alternative Pt catalysts, and the prospects and challenges of Pt-free CEs for the development of high-performance and low-cost DSSCs. 相似文献