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11.
关于粉体成球机盘体几何形状的研究 总被引:2,自引:2,他引:0
通过对粉体小球在粉体成球机盘底上运动轨线的研究,利用Euler定理,结合其参数特点,得到了不同几何形状的盘底在成球过程中对粉体小球运动的影响,球面盘底较平面盘底更有利于成球的结论。 相似文献
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螺旋翅片管的换热计算 总被引:1,自引:0,他引:1
本文引入区域平均表面传热系数的概念。在实验研究的基础上进行了肋基和肋端温度分布预测及肋片换热数值计算。 相似文献
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A compact lumped‐element equivalent circuit model of two‐layer integrated spiral inductors on silicon substrates is developed in this article. Based on this proposed model, excellent agreements are achieved between the measured and simulated S‐parameters for different inductors. Also, both self‐ and mutual inductances of two‐layer inductors are accurately extracted, and their overall performances are understood clearly. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 148–153, 2003. 相似文献
14.
Structure and Ordination of Epiphytic Invertebrate Communities of Four Coastal Wetlands in Green Bay,Lake Michigan 总被引:1,自引:0,他引:1
Epiphytic macroinvertebrate communities of four coastal wetlands of Green Bay, Lake Michigan were compared by taxonomic composition, feeding group composition, and environmental influences using Bray-Curtis ordination. Ordination scores from the most sheltered oligotrophic site, Portage Marsh, were distinct from the eutrophic, exposed sites located in middle and lower Green Bay— Seagull Bar, Little Tail Point, and Dead Horse Bay. Epiphyton chlorophyll a, phytoplankton chlorophyll a, and specific conductance strongly correlated to the ordination axes, indicating the trophic gradient within Green Bay was a primary environmental influence. The feeding group compositions at the sites were consistent with the type and abundance of food available. Portage Marsh is a scraper-shredder system, with macroinvertebrates feeding mainly on epiphyton and coarse particulate detritus. Dead Horse Bay and Little Tail Point are collector systems, sustained by phytoplankton and fine particulate organic matter. Seagull Bar is intermediate in trophic position along the ordination axes, but more closely resemble the latter two sites. The type and abundance of food resources available to these invertebrate communities are influenced by wave exposure, light attenuation, nutrient levels, and algae levels of the littoral and pelagial waters. Macroinvertebrate communities were sensitive to shifts in food resources, which generated shifts in trophic structure. 相似文献
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In order to increase the efficiency of waste utilization in thermal conversion processes, pre-treatment is advantageous. With the Herhof Stabilat® process, residual domestic waste is upgraded to waste-derived fuel by means of biological drying and mechanical separation of inerts and metals. The dried and homogenized waste-derived Stabilat® fuel has a relatively high calorific value and contains high volatile matter which makes it suitable for gasification. As a result of extensive mechanical treatment, the Stabilat® produced is of a fluffy appearance with a low density. A two-stage gasifier, based on a parallel-arranged bubbling fluidized bed and a fixed bed reactor, has been developed to convert Stabilat® into hydrogen-rich product gas. This paper focuses on the design and construction of the configured laboratory-scale gasifier and experience with its operation. The processing of low-density fluffy waste-derived fuel using small-scale equipment demands special technical solutions for the core components as well as for the peripheral equipment. These are discussed here. The operating results of Stabilat® gasification are also presented. 相似文献
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攀矿选钛厂设计采用传统的螺旋选矿设备FLX一1型φ600mm螺旋选矿机和φ1200mm螺旋溜槽,从选矿(铁)厂磁选尾矿物料中回收原生粒状钛铁矿积累了多年生产实践经验。而广东有色金属研究院研制的GL一2型φ600mm螺旋选矿机具有处理能力大、分选效率高、选别粒级宽、不需冲洗水及占地面积小等特点,有取代选钛厂目前使用的螺旋选矿设备之趋势。 相似文献
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本文就抗生素发酵生产过程,提出了一种补料时机的Fuzzy识别、预报的建模方法,并根据20m~3发酵罐工业数据的分析,选取了以总糖、总糖变化率、氨基氮和氨基氮变化率四个主要参数作为输入集因素,运用本文提出的方法,建立了一个实际的抗生素发酵生产过程补料时机的 Fuzzy 识别、预报模型。经现场调试效果良好,与富有经验的行家相比,准确率达90%以上。 相似文献
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