共查询到17条相似文献,搜索用时 140 毫秒
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采用物理模拟和数值模拟,研究了某钢厂250 t转炉底吹对熔池混匀时间、气液两相区速度、熔池低速区体积、炉底剪切力和气体能量利用率的影响。结果表明,熔池混匀时间随底吹气量增大而减少,随底吹孔数增加而减少。底吹孔数为12个时,底吹气量由15 L/min增至50 L/min,熔池混匀时间降低54.8%。底吹气量不变(50 L/min),底吹孔数由12个减至3个时,混匀时间增加52.9%。底吹枪数量减少,搅拌区域减小,熔池中“死区”和“低速区”体积比分别增加4.89%和28.9%。底吹枪减至3个时,单个底枪气量增大,气液两相区最大速度由0.34 m/s增至0.64 m/s,底吹孔处炉底所受剪切力增大52%,对炉底耐材寿命不利。从数值模拟结果也可发现,底吹工况的变化影响气体在熔池中的利用效率。底吹总气量增大时,熔池动能增加,但气体能量利用率降低。底吹气量较小时,底吹孔数的变化对气体能量利用率影响较小。底吹气量较大(50 L/min)时,相比于12个底吹孔,6个和3个底吹孔的气体能量利用率分别下降18.4%和23.3%。 相似文献
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在原油采输过程中会产生大量含油污泥,传统处理方式存在回收效率低、环境二次污染等弊端,应用超临界水气化含油污泥进行氢能回收,对含油污泥进行高效处理和利用具有重要意义。本文应用均匀设计方法研究超临界水的反应温度、反应压力、反应时间和物料比与最终单位污泥产氢量之间的关系,并通过反应结果拟合出它们之间的经验公式,分析超临界水反应参数对含油污泥气化制氢影响规律。结果表明,通过均匀设计进行多元线性拟合在含油污泥气化实验中具有较好的可行性,拟合出的经验公式具有良好的预测性,单位污泥产氢量与反应温度、反应时间呈正相关,与物料比呈负相关,伴随压力的增加单位污泥产氢量先增加后减小。在反应参数为544℃、2.2MPa、150min、10%下,单位污泥产氢量最高为5.92mmol/g。 相似文献
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高炉冶炼是一个具有非线性、大时滞、大噪声、分布参数等特征的高度复杂生产过程。针对目前高炉现场以焦比为能耗评价指标却无法提供实时指导的问题, 研究以一氧化碳利用率为能耗评价指标, 提出一种基于改进支持向量机的高炉一氧化碳利用率预测方法。首先分析高炉炼铁过程机理, 结合互信息法得出影响一氧化碳利用率的相关操作因素。然后鉴于生产数据含噪高的特点, 采用小波去噪方法去除数据噪声干扰, 并且利用灰色相对关联度分析方法对操作参数进行时序配准, 消除时滞影响, 建立高炉一氧化碳利用率预测模型。在建模过程中, 将自适应粒子群与支持向量机回归方法相结合, 以克服模型参数选择的随机性, 提高了模型预测精度。现场实际数据的预测结果表明所提出方法的有效性, 能够实时精确地预测高炉一氧化碳利用率, 为后续高炉的优化操作和节能减排提供了及时有效的决策支持。 相似文献
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均匀设计法优选辅酶Q10的超声提取工艺 总被引:6,自引:2,他引:4
用均匀设计法优化了以新鲜烟叶为原料,超声提取辅酶Q10的工艺。考察了超声时间、温度、液料比和超声功率4个因素对辅酶Q10提取率的影响,并对提取过程用多元回归方程进行了数值模拟。实验得到优化的辅酶Q10超声提取工艺条件为:提取溶剂体积分数85%乙醇,液料体积质量比18 mL/g,超声温度45℃,超声时间45 m in,超声功率250 W。结果表明,超声法提取对烟叶中辅酶Q10的提取质量分率为7.12×10-6,其提取率是索氏提取的1.34倍,实验结果与回归方程的拟合值吻合良好,说明应用超声法提取烟叶中的辅酶Q10是可行的。 相似文献
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Yang Cao Qirong Xia Baishan Fang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(1):109-112
This paper is concerned with the optimization of expression conditions of 1,3‐propanediol oxidoreductase (PDOR) using the uniform design (UD) method and regression analysis. The concentration of the inducer isopropyl‐β‐D ‐thiogalactopyranoside (IPTG), the induction temperature and the induction time, which were identified as three crucial factors, were optimized in 50 mL cultivation tubes containing 5 mL LB culture. The optimal expression conditions for enhanced PDOR activity were found to be an IPTG concentration of 0.1 mmol l?1, an induction temperature of 21.2 °C and an induction time of 5 h. Subsequent experimental trials confirmed the validity of the model. These optimal expression conditions in the cultivation tube culture led to a PDOR activity of 9.25 U mL?1, which was considerably higher than those obtained in the optimizing experimental trials. Copyright © 2005 Society of Chemical Industry 相似文献
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以醋酸纤维素为包裹材料、聚乙二醇800为相变材料、N,N-二甲基乙酰胺和丙酮为溶剂,采用静电纺丝法制备相变储湿纤维。基于均匀设计和多元非线性回归法研究了各因素对静电纺丝相变储湿纤维综合热-湿性能的影响。结果表明,各因素对性能影响的主次顺序为:聚乙二醇800用量>N,N-二甲基乙酰胺用量>醋酸纤维素用量>反应温度>干燥温度;优化制备方案:N,N-二甲基乙酰胺用量为11.3 g、醋酸纤维素用量为6.96 g、聚乙二醇800用量为8.12 g、反应温度为37.8 ℃、干燥温度为60.4 ℃. 相似文献
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铜冶炼烟气制酸尾气烟囱冒白烟的常见原因及分析 总被引:1,自引:0,他引:1
简要介绍了鼓风炉铜冶炼烟气制酸工艺的特点,以生产中出现过的问题为依据,对尾气烟囱冒白烟问题进行分析和探讨,实现尾气“无烟”达标排放应重点控制好水分、吸收率及酸雾指标。 相似文献
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Various color models have been developed to represent color as a synthetic construct of its component attributes. The CMYK color model is based on a mathematical framework efficient for digitally planning and processing the colors for a domain‐specific application such as interior design. The CMYK color model correlated with the Munsell system would also increase usability and effectiveness. In this research, we suggest a computationally assisted systematic method to formulate a color palette useful for interior design. A continuous process of sampling, statistical analysis, and computational manipulations has been performed to derive a desirable color palette. First, color samples have been extracted from the representative interior design cases of residential buildings, offices, and commercial spaces. Second, the interrelationships among C, M, Y, and K values in all samples have been statistically analyzed followed by calculating the number of elements in the numerically categorized sets for C, M, or K value. New CMYK combinations were generated by using selected sets of C, M, or K value showing relatively dominant presence in the original samples. Then, the statistically extracted correlation function was used to propose a complete list of CMYK color combinations for interior design. The resulting CMYK combinations were then converted into the values represented in the Munsell color system. We envision that the proposed approach can increase both applicability and efficiency of the resulting color palette by considering both intuitive and mathematical color models with the support of a computational data processing technique. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 135–145, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20092 相似文献