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61.
采用分隔壁精馏塔分离裂解汽油。建立了分隔壁精馏塔小试装置,该装置主塔的理论板数57块,副塔的理论板数为16块。考察了回流比、液体分配比和侧线采出量对分离效果的影响,同时用Aspen Plus 软件对分隔壁精馏塔进行模拟。结果表明,最佳操作条件为进料速率4.7 kg/h、塔顶出料速率0.84 kg/h、侧线采出速率3.0 kg/h、液体分配比3、回流比5.5。在此条件下,塔顶C5的质量分数达到99.60%,侧线C6~C8的质量分数达到99.76%,实验结果与模拟结果基本一致。采用分隔壁精馏塔比常规分离流程可使再沸器能耗降低20.8 %。 相似文献
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自卸车举升、翻转、倾卸物料时整车稳定性将会降低,特别是重型自卸车,其车厢很长,刚度低,卸货时车架、车厢可能产生严重扭曲,甚至引发整车倾翻事故,造成人员伤亡和财产损失.为提高车厢的刚度,增加自卸车举升卸货时的稳定性,将车厢设计成分体式,实现三向卸货,并对多种卸货方式进行稳定性计算.通过对分体式车厢与整体式车厢实例进行稳定性计算比较,说明分体式车厢的设计是科学和实用的. 相似文献
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分场景2G/3G互操作与功率参数优化 总被引:1,自引:1,他引:0
武晓华 《电信工程技术与标准化》2012,25(2):16-20
互操作优化目标就是把2G/3G网络有效结合起来,针对现网具体情况,我们将全网小区按照覆盖场景不同进行划分,对不同厂商设备规定统一标准的互操作参数及功率参数,从而保证2G/3G互操作的规范性、准确性,同时提升优化工作效率。实践证明,经过分场景2G/3G互操作与功率参数优化后,切换成功率、掉话率等指标有较大提高,客户感知也得到提升。 相似文献
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本文将中小口径抛物面天线反射体,按口径大小分成三个系列。从机械性能、造型美学和价值工程、六性要求等角度论述了中小口径天线的基本特点,并在此基础上提出了设计的基本思路。 相似文献
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The problem of steady, laminar, natural convection flow in a porous enclosure divided by a triangular massive partition has been formulated. The massive triangular partition is a solid adiabatic body which is located to the right and top wall. Bottom and left vertical wall of porous enclosure are isothermally heated and cooled, respectively. Remaining wall is adiabatic. Governing equations using Darcy model are solved numerically by the finite-difference method and the Successive Under Relaxation (SUR) technique is used to solve linear algebraic equations. Thanks to massive partition, two different enclosure are formed, depends on dimensions of the triangular body, as triangle and trapezoidal. Flow patterns and temperature distributions were presented at different aspect ratios (0 ≤ AR ≤ 1) and Rayleigh numbers (100 ≤ Ra ≤ 1000). Results are given for different aspect ratios (AR) for AR = 0, 0.25, 0.50, 0.75 and 1. A parametric study is conducted and a set of representative results for flow and temperature characteristics are presented and discussed. 相似文献
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The authors examined recognition memory for words or visuospatial patterns under full (FA) or divided attention (DA) conditions with a distracting task requiring either phonological (rhyme) or visuospatial (curved-line) processing of letters, in 72 young adults. The authors found an interaction such that the curved-line distracting task had a more detrimental effect on corrected recognition, and discriminability measured by d′, for spatial patterns than did the rhyme distracting task, whereas the reverse was true for memory of words. There was also a general effect of DA on response bias such that C increased under DA relative to FA conditions, regardless of the distracting task, and type of information being remembered. Results suggest memory interference from DA at retrieval is process-specific, and that DA at retrieval leads to a more conservative response strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The authors investigated the effect of divided attention, study-list repetition, and age on recollection and familiarity. Older and younger adults under full attention and younger adults under divided attention at study viewed word lists highly associated with a single unstudied word (critical lure) once or three times, and subsequently performed a remember-know recognition test. Younger adults made fewer false remember responses to critical lures from repeated study lists, whereas younger adults under divided attention and older adults both showed an increase with repetition. Findings suggest older adults' susceptibility to illusory memories is related to a deficit in available attention during encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献