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造成橡胶直角形撕裂强度测试结果偏差的原因分析 总被引:1,自引:0,他引:1
采用不同裁刀裁切3种胶料试样,并由不同操作人员测试其直角形撕裂强度。根据试验结果分析了造成直角形撕裂强度测试结果差异的主要原因:不同试验人员因测试习惯不同会造成测试结果的差异;裁刀顶角的曲率半径不同也会造成测试结果不同,使用顶角尖锐裁刀时测试数据偏小,反之测试数据偏大;不同胶料受不同裁刀影响的程度不同,抗撕性能好的受影响较小,抗撕性能差的受影响较大。 相似文献
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酸化工艺技术是油田开发常用的一种提高产量的有效措施,而不同的因素对酸化效果的影响也不尽相同,不同区块的有着不同的地质条件,最适合的酸化类型也不同。本文简介了通过模糊数学法选出不用因素的影响强度,举例说明了不同区块的根据不同的地质条件选用不同的酸化措施类型。 相似文献
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良友 《精细化工原料及中间体》2008,(4)
一、柔软整理中常见质量问题
1、达不到应有手感 柔软整理的柔软风格随客户要求不同而不同.如柔软、平滑、蓬松、柔糯、油滑、干滑等.根据不同的风格选用不同的柔软剂。如软片中.有不同结构的柔软剂软片。其柔软度、蓬松度、滑度、泛黄情况、影响织物吸水性等均不同;在硅油中,不同改性基因的改性硅油性能也不同,如氨基硅油、羟基硅油,环氧改性硅油、羧基改性硅油等性能均不同。 相似文献
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<正>在肥料的选用中,必须考虑肥料不同养分的形态。各种作物不仅对养分形态的需求有差别,而且对不同形态养分吸收能力也不同;同一作物、不同品种及不同生长时期需肥情况也有差异。因此,掌握不同肥料形态的特性,充分发挥各种肥料效用非 相似文献
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钢铁氧化工艺应根据不同的零件状态,采取不同的生产措施。钢铁紧固件在碱性氧化工艺中,常见的不合格品为表面发红,根据不同紧固件的材料和表面状态,详细分析了发红的不同类型以及发红的不同原因,并提出了相应的解决方案。 相似文献
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随着关系型数据库系统的不断发展,不同系统开发工具生产商,提供了不同的数据库访问方式,不同的数据库供应商提供了不同的数据库接口,致使现在存在着很多不同的数据库访问技术,本文对几种流行的数据库访问方式进行了总结和比较。 相似文献
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结合相关规范,针对化工企业中常见的爆炸危险气体环境进行了探讨,旨在使设计人员重视爆炸危险气体环境的划分及防爆电气设备的选型. 相似文献
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Kai Liu Saif R. Kazi Lorenz T. Biegler Bingjian Zhang Qinglin Chen 《American Institute of Chemical Engineers》2020,66(5):e16908
The increasing penetration of unconventional gas and liquefied natural gas poses an operational challenge on existing regional gas networks for gas quality problems. A new dynamic model for natural gas pipeline network with multiple supplies is presented with a special emphasis on gas interchangeability control. Wobbe index serves as gas interchangeability indicator and is calculated by equations derived from rigorous composition-based partial differential equations. Disjunctive formulation is applied to represent different modes of gas blending due to gas reversal, and the disjunctive model is then reformulated as a nonsmooth model with min/max and absolute value functions, which is solved by a gradient-based nonlinear program solver after smooth approximation. Moreover, a heuristic algorithm is proposed to tune the penalty parameters in order to focus on different penalty terms while keeping the model well-conditioned. The developed model and strategy are first tested with a small pipeline network model and then extended to a large model. The results show that the model can effectively manage gas interchangeability issues in pipeline networks within reasonable CPU time. 相似文献
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Operational strategy and planning for raw natural gas refining complexes: Process modeling and global optimization
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Bing J. Zhang Qing L. Chen Jie Li Christodoulos A. Floudas 《American Institute of Chemical Engineers》2017,63(2):652-668
Optimal operational strategy and planning of a raw natural gas refining complex (RNGRC) is very challenging since it involves highly nonlinear processes, complex thermodynamics, blending, and utility systems. In this article, we first propose a superstructure integrating a utility system for the RNGRC, involving multiple gas feedstocks, and different product specifications. Then, we develop a large‐scale nonconvex mixed‐integer nonlinear programming (MINLP) optimization model. The model incorporates rigorous process models for input and output relations based on fundamentals of thermodynamics and unit operations and accurate models for utility systems. To reduce the noncovex items in the proposed MINLP model, equivalent reformulation techniques are introduced. Finally, the reformulated nonconvex MINLP model is solved to global optimality using state of the art deterministic global optimization approaches. The computational results demonstrate that a significant profit increase is achieved using the proposed approach compared to that from the real operation. © 2016 American Institute of Chemical Engineers AIChE J, 63: 652–668, 2017 相似文献
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目前对危险气体泄漏防护区域的划分方法主要为定性方法,难以对具体场景定量表征,进而无法用于风险防控系统的设计规划。本文在等价气云理论的基础上,基于爆炸事故后果风险评估,提出一种定量划分气体防护区域的方法。综合考虑气体泄漏概率、风速风向联合分布概率等现场特征要素,运用高斯扩散模型,得到气体泄漏扩散的等价气云体积以及气体泄漏扩散风险集合,并进行泄漏场景筛选。针对扩散风险较大的场景进行点火概率分析,利用多能法计算气云爆炸影响范围,对气云爆炸事故进行风险评估得到爆炸事故后果风险集合。在ALARP标准与火气系统探测器场景覆盖率的指导下,依据不同装置区域的风险值确定气体防护区域等级定量划分标准。通过某LNG接收站案例分析,可定量得到不同装置的防护区域等级,实现针对具体泄漏场景的气体防护区域等级定量划分。数值计算表明,气体防护区域定量划分可为火气系统探测器布设提供理论支持。 相似文献
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采用κ-ε二方程模型和欧拉多相流模型,对一种单筒单级气升式气液环流反应器内的湍流气液两相流进行了全尺寸的数值模拟研究,考察了采用3种不同气体分布器时反应器内气含率和流速分布的细节.模拟结果表明不同结构的分布器对总体气含率和内筒中的两相速度分布有很大影响,因而对气含率分布和气液两相接触效果有较大影响,从而对反应过程产生影响.单环分布器产生的气液两相接触效果较差,对于反应过程很不利.对于大直径的环流反应器推荐使用多环分布器.计算所得的整体气含率与实测的整体气含率进行了对比,吻合较好. 相似文献
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Keliu Wu Xiangfang Li Chenchen Wang Zhangxin Chen Wei Yu 《American Institute of Chemical Engineers》2015,61(6):2079-2088
A model for gas transport in microfractures of shale and tight gas reservoirs is established. Slip flow and Knudsen diffusion are coupled together to describe general gas transport mechanisms, which include continuous flow, slip flow, transitional flow, and Knudsen diffusion. The ratios of the intermolecular collision frequency and the molecule‐wall collision frequency to the total collision frequency are defined as the weight coefficients of slip flow and Knudsen diffusion, respectively. The model is validated by molecular simulation results. The results show that: (1) the model can reasonably describe the process of the mass transform of different gas transport mechanisms; (2) fracture geometry significantly impacts gas transport. Under the same fracture aperture, the higher the aspect ratio is, the stronger the gas transport capacity, and this phenomenon is more pronounced in the cases with higher gas pressure and larger fracture aperture. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2079–2088, 2015 相似文献