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Reliability Sensitivity Algorithm Based on Stratified Importance Sampling Method for Multiple Failure Modes Systems

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Chinese Journal of Aeronautics 2010年第6期23卷 660-669页

作者： Zhang Feng Lu Zhenzhou cui lijie Song Shufang School of Mechanics and Civil and Architecture Northwestern Polytechnical University Xi 'an 710072 China School of Aeronautics Northwestern Polyteehnical University. Xi 'an 710072 China

Combining the advantages of the stratified sampling and the importance sampling, a stratified importance sampling method （SISM） is presented to analyze the reliability sensitivity for structure with multiple failure modes. In the presented method, the variable space is divided into several disjoint subspace by n-dimensional coordinate planes at the mean point of the random vec- tor, and the importance sampling functions in the subspaces are constructed by keeping the sampling center at the mean point and augmenting the standard deviation by a factor of 2. The sample size generated from the importance sampling function in each subspace is determined by the contribution of the subspace to the reliability sensitivity, which can be estimated by iterative simulation in the sampling process. The formulae of the reliability sensitivity estimation, the variance and the coefficient of variation are derived for the presented SISM. Comparing with the Monte Carlo method, the stratified sampling method and the importance sampling method, the presented SISM has wider applicability and higher calculation efficiency, which is demonstrated by numerical examples. Finally, the reliability sensitivity analysis of flap structure is illustrated that the SISM can be applied to engineering structure.

关键词： multiple failure modes reliability sensitivity Monte Carlo simulation stratified sampling method importance sam-piing method stratified importance sampling method (SISM)

Integration of coal pyrolysis process with iron ore reduction： Reduction behaviors of iron ore with benzene-containing coal pyrolysis gas as a reducing agent

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Chinese Journal of Chemical Engineering 2016年第6期24卷 811-817页

作者： Xin Li Helong Hui Songgeng Li Lu He lijie cui State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a model tar compound. Variables such as reduction temperature, reduction time and benzene concentration are studied. The carbon deposition of benzene results in the retarded iron reduction at low temperatures. At high temperatures over800 °C, the presence of benzene in the gas can promote iron reduction. The metallization can reach up to 99% in20 min at 900 °C in the presence of benzene. Significant increases of hydrogen and CO/CO2 ratio are observed in the gas. It is indicated that iron reduction is accompanied by the reforming and decomposition of benzene. The degree of metallization and reduction increases with the increasing benzene concentration. Iron oxide can nearly completely be converted into cementite with benzene present in the gas under the experimental conditions. No sintering is found in the reduced sample with benzene in the gas.

关键词： Coal pyrolysisIron reductionIntegrationTar effect

Numerical analysis of enhanced mixing in a Gallay tote blender

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Particuology 2016年第6期14卷 95-102页

作者： Xinxin Ren Guangzheng Zhou Ji xu lijie cui Wei Ge State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing 100049 China

The mixing performance of a multi-bladed baffle inserted into a traditional Gallay tote blender is explored by graphic processing unit-based discrete element method software. The mixing patterns and rates are investigated for a binary mixture, represented by two different colors, under several loading profiles. The baffle effectively enhances the convective mixing both in the axial and radial directions, because of the disturbance it causes to the initial flowing layer and solid-body zone, compared with a blender without a baffle. The axial mixing rate is affected by the gap between the baffle and the wall on the left and right sides, and an optimal blade length corresponds to the maximum mixing rate. However, the radial mixing rate increases with the blade length almost monotonically.

关键词： Powder mixing Tote blender Granular materials Discrete element method Simulation Baffle

Distribution of Mid-deeply Buried Sand-bodies and their Hydrocarbon Significance at Basin Margins: Case Study of the Paleogene in the Eastern Liuzan Area of the Nanpu Sag, Bohai Bay Basin, China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1279-1294页

作者： cui lijie JIAN Shikai ZHANG Boming XIE Xiongju LI Liang School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Beijing Ultrado Resources Technology Inc. Beijing 100083China Research Institute of Exploration and Development PetroChina Jidong Oilfield CompanyTangshanHebei 063004China

The current research aims to unlock the temporal and spatial distribution of sand-bodies and their relationship with hydrocarbon accumulation in the mid-deep layer of basin margins, located in the eastern part of the Liuzan area of the Nanpu Sag, Bohai Bay Basin, China. Through this study, the main target interval of the area was divided into two fourthorder sequences. The lean sand mixed sedimentary belt with great importance in controlling hydrocarbon accumulation was identified through the comprehensive use of 3 D seismic data, logging data, lithological data and seismic inversion data. A detailed analysis of sand-body development characteristics and their role in controlling hydrocarbon accumulation was conducted. The results reveal that the study area mainly develops two distinct fan-delta lobes from the NE-trending sediment supply direction. Due to the relatively high influence of the lacustrine transgression event, the scale of the lean sand mixed sedimentary belt within the SQ1-1(the lacustrine transgressive systems tract) is relatively small, showing a relatively continuous distribution of sand bodies in the plane. Conversely, due to the relatively high impact of the lacustrine regression event, the scale of the lean sand mixed sedimentary belt developed within the SQ1-2(the highstand systems tract) is relatively large, the two east sets of fan-delta sedimentary systems being clearly separated. The lean sand mixed sedimentary belt formed a good lateral occlusion belt in favor of hydrocarbon accumulation. Through composite analysis of structural interpretation results, sand-body distribution and well test data, it is evident that the lean sand mixed sedimentary belt located in the structural high is not a favorable zone for hydrocarbon accumulation. In contrast, the wing of the high part of the structure is the zone of sand-bearing bodies and is a favorable zone of hydrocarbon accumulation.

关键词： lithological reservoirs sequence stratigraphy fan-delta sand-body correlation hydrocarbon accumulation

Formation of uniform reduced graphene oxide films on modified PET substrates using drop-casting method

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Particuology 2014年第6期12卷 66-73页

作者： Chunlin Zhao Li Xing Junhui Xiang lijie cui JianbinJiao Huazheng Sai Zhenyou Li Fei Li College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering University of the Chinese Academy of Sciences College of Engineering and Information Technology University of the Chinese Academy of Sciences

In this work,uniform reduced graphene oxide（RGO） films were formed on poly-（ethylene terephthalate）（PET） substrates using a simple drop-casting *** investigated four types of substrates：unmodified PET,polydopamine-coated ***-group-modified PET,and alkyl-group-modified *** water evaporation,the surface of the polydopamine-modified PET substrates can interact with the reduced graphene oxide sheets to form flattened and continuous RGO films,which exhibit a sheet resistance of 21.75 kΩ/sq at 82% *** result indicates that the properties of the surface groups determined whether uniform and flattened RGO films could be formed on the ***,we proposed a simple and effective way to produce transparent and conductive films in which the catechol unit exhibits a great effect on the deposition of uniform RGO films on PET substrates.

关键词： Reduced graphene oxide Modified PET substrates Drop-casting Polydopamine Transparent conductive films

Moment-independent importance measure of basic random variable and its probability density evolution solution

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Science China(Technological Sciences) 2010年第4期53卷 1138-1145页

作者： cui lijie,Lü ZhenZhou & ZHAO XinPan School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China School of Aeronautics Northwestern Polytechnical University Xi’an China

To analyze the effect of basic variable on failure probability in reliability analysis,a moment-independent importance measure of the basic random variable is proposed,and its properties are analyzed and *** on this work,the importance measure of the basic variable on the failure probability is compared with that on the distribution density of the *** use of the probability density evolution method,a solution is established to solve two importance measures,which can efficiently avoid the difficulty in solving the importance *** numerical examples and engineering examples are used to demonstrate the proposed importance measure on the failure probability and that on the distribution density of the *** results show that the proposed importance measure can effectively describe the effect of the basic variable on the failure probability from the distribution density of the basic ***,the results show that the established solution on the probability density evolution is efficient for the importance measures.

关键词： basic random variable moment-independent importance measure probability density evolution method

Biosynthesis and metabolic regulation of tropane alkaloids in Anisodus acutangulus

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Biosynthesis and metabolic regulation of tropane alkaloids i...

2013全国植物生物学大会

作者： KAI Guoyin TENG Xiaojuan cui lijie Development Center of Plant Germplasm Resoureces College of Life and Environment SciencesShanghai Normal University

Tropane alkaloids(TA) including anisodamine,anisodine,hyoscyamine and scopolamine are a group of important anticholinergic drugs with rapidly increasing market demand. Anisodus acutangulus is a solanaceous perennial plant that is endemic to China with good potential for TA production and classified as an endangered species in China,so it is significant to improve TA production in this resource plant by biotechnological *** the past few years,hairy root culture system for the medicinal plant *** was successfully developed and optimized using Agrobacterium rhizogenes in our *** important genes such as AaPMT1,AaPMT2,AaTRI,AaTRII and AaH6H involved in tropane alkaloids biosynthesis pathways have been successively isolated by our lab from *** correlation between expression of TA biosynthetic genes and TA accumulation in *** hairy root cultures were also investigated,in response to biotic and abiotic elicitors,respectively. Production of TA was significantly enhanced by overexpressing AaTRI and/or AaH6H as well as AaPMT in transgenic hairy root lines than that in the *** above results suggested that metabolic engineering strategy provide a powerful tool for enhancement of TA content in transgenic ***.

关键词： A.acutangulus tropane alkaloids(TA) hairy root metabolic engineering

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核函数的性质及其在灵敏度分析上的应用

西北工业大学学报 2010年第5期28卷 797-802页

作者：王奇吕震宙崔利杰西北工业大学航空学院陕西西安710072

推导了多维随机变量情况下不含交叉项的二次功能函数统计矩对基本变量分布参数灵敏度的通用解析表达式。基于核函数的性质,对正态分布情况给出了二次不含交叉项功能函数统计矩对基本变量分布参数灵敏度的理论解,并给出了该情况下失效概... 详细信息

推导了多维随机变量情况下不含交叉项的二次功能函数统计矩对基本变量分布参数灵敏度的通用解析表达式。基于核函数的性质,对正态分布情况给出了二次不含交叉项功能函数统计矩对基本变量分布参数灵敏度的理论解,并给出了该情况下失效概率对基本变量分布参数灵敏度的近似表达式。证明了三分布参数情况下前三阶统计参数之间的独立性,并在此基础上以三参数W eibull分布为例推导了其核函数的性质,将这些性质代入功能函数统计矩灵敏度的通用解析表达式,即可解析求得三参数W eibull分布情况下函数统计矩对基本变量分布参数的灵敏度。数字仿真算例结果表明:所推导的函数统计矩的灵敏度解析表达式是正确的,所推导的失效概率灵敏度近似表达式也具有较高的计算精度。

关键词：核函数可靠性灵敏度统计参数分布参数

曳力模型和湍流模型对内环流反应器数值模拟的影响

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化工学报 2018年第1期69卷 389-395页

作者：张佳宝崔丽杰杨宁中国科学院大学化学科学学院北京100049 中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190

研究了曳力模型和湍流模型对气升式内环流反应器流体力学参数的影响,进一步证实了DBS-Local曳力模型在气升式内环流反应器中的适用性。结果表明:曳力模型决定了是否可以模拟出下降管中的气体;而曳力模型和湍流模型共同作用,决定了气含... 详细信息

研究了曳力模型和湍流模型对气升式内环流反应器流体力学参数的影响,进一步证实了DBS-Local曳力模型在气升式内环流反应器中的适用性。结果表明:曳力模型决定了是否可以模拟出下降管中的气体;而曳力模型和湍流模型共同作用,决定了气含率模拟结果的准确性。Schiller-Naumann、Tomiyama、Grace、Ishii-Zuber这4种曳力模型均无法预测出下降管含气这一现象,而DBS-Local曳力模型能够模拟出下降管中的气体。DBS-Local曳力模型与standard k-εmixture湍流模型组合,对气含率的预测值与实验值较为接近,而与RNG k-ε dispersed湍流模型组合,对轴向液速的预测值与实验值更为接近。

关键词：计算流体力学内环流反应器气液两相流曳力模型湍流模型气含率