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排序方式: 共有123条查询结果,搜索用时 15 毫秒
101.
Qian Xu Weiqi Zhang Jian Zhao Lei Xing Qiang Ma Li Xu 《International Journal of Green Energy》2018,15(3):181-188
Unlike the situation in the direct methanol fuel cell (DMFC) fed with dilute liquid methanol solution, the required water in anode for a DMFC fed with neat methanol is entirely transported from cathode. In this study, the water concentration in anode catalyst layer of such a DMFC operating with fully active mode is theoretically analyzed, followed by the experimental investigations on the effects of air flow rate and operating temperature on cell performance. The results revealed that the air flow rate has a strong impact on cell performance, especially at larger current density. Overmuch air causes rapid decline of cell performance, which results from the dehydration of membrane and lack of water in the anode reaction sites. Raising temperature induces faster reaction kinetics, while undesired stronger water dissipation from the DMFC. In practice, the stable cell resistance can be used as a criterion to help the DMFC to achieve a high and sustainable performance by finely combining the air flow rate and operating temperature. 相似文献
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Sumate Kunsa-Ngiem Pongsak Lowmunkhong Mourad Harir Philippe Schmitt-Kopplin Somyote Sutthivaiyakit 《Journal of environmental science and health. Part. B》2013,48(11):738-745
AbstractA magnetic molecularly imprinted polymer (MMIP) for chloramphenicol was prepared using a surface-imprinted and microwave-heating-induced polymerization method. The surfaces of the magnetic particles were first double-bond functionalized with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), followed by the copolymerization of 4-vinyl pyridine (4-VP) and trimethylolpropane trimethacrylate (TRIM) in the presence of chloramphenicol as a template and 1,1-azobis(cyclohexane-carbonitrile) (ABCN) as an initiator in a mixture of dimethyl sulfoxide and water with microwave heating at 80°C. The magnetic polymer possesses supraparamagnetic properties and was used to concentrate and cleanup chicken feed extract, followed by chromatographic separation using a Lichrospher®100 RP C8 column and detection with two multi-reaction monitoring transitions at m/z 321→ 152 and m/z 321→ 257. The mean recoveries obtained at two spiking levels were in the range of 94.6–100% The relative intra- and inter-day standard deviations were in the range of 1.4–2.6% and 5.1–5.7%, respectively. The detection limit of the method was 0.12 µg kg?1. This confirmatory method was successfully applied to determine chloramphenicol in chicken feed samples. 相似文献
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在污水处理场,经过生化处理后的排放水中仍含有一定的悬浮物、氨、氮、油、菌类及大量的溶解盐类,其COD也较高,因而不能直接用于锅炉补水。用“斜板沉降-连续过滤-超滤-反渗透”这一组合工艺来处理炼油污水,并将处理后的污水回用于锅炉补水。对其可行性进行了科学的分析和论述,并进行了中试。试验证明,该工艺流程及设备无论在技术上还是在经济上都是可行的。 相似文献
107.
Concentrations of additive arsenic in Beijing pig feeds and the residues in pig manure 总被引:17,自引:0,他引:17
The swine industry in China has grown rapidly over last two decades. Great amount of pig manure is generated in China, which can be used as organic fertilizers on agricultural lands. Meanwhile, the organic arsenic compounds have been used as feed additives for swine disease control and weight improvement. Once the excessive additives are released in the environment, arsenic may compromise food safety and environmental quality. There is a growing public concern about the arsenic residues accumulation in pig manure, however, little work has been done to investigate the exact arsenic content in pig feed and the residues in manure in China This study investigates the concentrations of arsenic in 29 pig feed samples and 29 manure samples collected from eight pig farms in the Chaoyang district, Beijing city. The detected rate of arsenic in 29 couples of samples was 100%. The concentrations of arsenic in pig feeds and manures ranged from 0.15 to 37.8 mg/kg and 0.42 to 119.0 mg/kg, respectively. The result showed that arsenic concentration in pig manure will be greatly elevated when the arsenic in pig feed was largely increased. The loading rates of pig manure in fourteen Beijing counties and districts were in the range of 2.7–57.2 t/ha yr. Accordingly, the potential soil arsenic increase rates resulting from land application of pig manure might range between 11.8 and 78.9 μg/kg yr. Despite these findings, it is too early to draw the conclusion that arsenic pollution from pig manure is serious in Beijing farmland; therefore, longitudinal studies about the chemical form transformation and the environmental behaviors of pig manure arsenic are required in order to come up with more definitive conclusions. 相似文献
108.
Improvement in the feeding method to an inclined conveyor designed for the recycling of foundry sand
H. Ohya S. Endoh T. Honma Y. Hamano 《Journal of Material Cycles and Waste Management》2003,5(1):0049-0054
The goal of the inclined conveyor method for particle shape separation is to process a large amount of feed material for
recycling technology. The high feed rate has been achieved because the movement of particles is faster than for other previously
introduced equipment. The separation performance of the apparatus was tested with foundry sand. A large amount of sand was
treated, and various processing capacities were studied experimentally. The feed method was improved from point to line with
wide troughs to process the higher feed rate. We succeeded in attaining a feed rate of 1.49 × 10−3 kg/s with a 0.3-m trough. The space filling, which was an important factor in deciding the capacity of the feed rate, was
defined. This method is useful for any kind of line-feed method.
Received: March 25, 2002 / Accepted: August 5, 2002 相似文献
109.
进行了将流动电流混凝投药自动控制系统应用于 4种受污染水源水的试验 ,研究了该系统检测灵敏度受污染物的影响情况。试验结果表明污染物的存在使流动电流的检测灵敏度降低 ,污染物的组成成分和浓度等都是影响灵敏度的主要因素 ,但是流动电流与投药量的相关性仍然存在。在CODMn不超过 10mg L或油类物质浓度 <2~ 10mg L ,时 ,污染物的影响程度较小 ,将流动电流混凝投药控制技术应用于此条件下的受污染水源水是可能的。 相似文献
110.
利用Excel2000电子数据表格软件提供的线性规划对畜禽的饲料配方寻求最优解,具有科学、运算速度快、增减原料随意和数据修改容易等优点,可以省去手工计算饲料配方的繁琐,与研制出来的专家系统饲料配方软件及相关计算机设计饲料配方的程序相比,该方法无须要求使用者首先购买这些软件和程序,只要用户购买电脑并安装上Excel7000电子数据表格软件后即可运用线性规划设计饲料配方。 相似文献