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Hydrodynamic Instability Analysis of the Axial Flow Pump in an Ethylene Polymerization Loop Reactor

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China Petroleum Processing & Petrochemical Technology 2022年第1期24卷 135-148页

作者： Lu Jin Yang Yao Sun Jingyuan Huang Zhengliang Yang Yongrong Wang Jingdai Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058 State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058

The hydrodynamic instability of the axial flow pump in a loop reactor has long been a troubling issue to be solved in the polyethylene industry due to the lack of a better mechanismic understanding.Generally,the instability of an axial flow pump can be reflected by the fluctuation of the pump head.In this study,the transient computational fluid dynamics(CFD)simulation is adopted to study the hydrodynamic instability of the axial flow pump used in an ethylene polymerization loop reactor.The results show that the pump head under single liquid phase nearly remains constant while the pump head under slurry phase fluctuates due to the variation of solid volume fraction distribution in the pump.Besides,under the combined effect of the maximum solid volume fraction difference in the pump and the turbulence intensity of the liquid phase,the fluctuation of the pump head under slurry phase increases when the solid volume fraction in the loop reactor increases from 0.10 to 0.29,and the fluctuation decreases,when the solid volume fraction increases from 0.29 to 0.35.Furthermore,there is a negative correlation between the pump head and the solid volume fraction in the pump;with the increase of solid volume fraction in the loop reactor,and the correlation coefficient increases as well.Moreover,a‘spiral particulate band’phenomenon is formed in the ascending leg caused by three mechanisms,viz.:the segregation of particles in all bends,the dispersion of particles by the secondary flow in the ascending leg,and the rotational movement of particles in the pump.

关键词： axial flow pump loop reactor CFD hydrodynamic instability polyethylene

Acidity Modification of ZSM-5 for Methane Conversion in Co-feeding Method with MTA Reaction

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Chemical Research in Chinese Universities 2022年第4期38卷 1012-1017页

作者： YU Yue XI Zhixiang ZHOU Bingjie JIANG Binbo LIAO Zuwei YANG Yao WANG Jingdai Huang Zhengliang SUN Jingyuan YANG Yongrong Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027P.R.China

Acidity plays a vital role in methane conversion by co-feeding method,which is one of the best strategies to improve the utilization and gentle the reaction conditions of methane.In this work,Zn,Ni,Mo,La,Ga,Fe and Co-impregnated ZSM-5 zeolites have been prepared with the same substitutions to variate the acidities and tested in co-aromatization of methanol with methane.It is demonstrated that the new medium-strong acid sites formed by metal and strong acid sites are the key role to activate methane in co-reaction.Zn-modified ZSM-5 catalyst is preferred to exhibit the best methane conversion of 12%,whose aromatic selectivity increases from 27.2%to 52.2%compared with that of HZSM-5.Besides,the addition of methane further improves the production of high-valued aromatics compared with methanol to aromatics(MTA)reaction.

关键词： Methane Methanol to aromatics(MTA) Co-reaction Acid site

Distribution and depositional model of microbial carbonates in the Ordovician middle assemblage,Ordos Basin,NW China

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Petroleum Exploration and Development 2021年第6期48卷 1341-1353页

作者： WEI Liubin ZHAO Junxing SU Zhongtang WEI Xinshan REN Junfeng Huang Zhengliang WU Chunying State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Exploration and Development Research Institute of PetroChina Changqing Oilfield Company Xi’an 710018China National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields Xi’an 710018China

Based on outcrop profiles,drilling cores,cast thin sections etc.,the types,microfacies combinations and distribution pattern of microbial carbonates in the Ordovician middle assemblage of the mid-eastern Ordos Basin have been systematically analyzed.The middle assemblage of Ordovician in the mid-eastern Ordos Basin has microbial carbonates formed by the calci-fication of cyanobacteria,including microbial biostromes and microbial mounds made of stromatolites,thrombolites,and on-colites.The distribution of the carbonates shows obvious“stratum-control”and“regional”characteristics.The microbial bio-stromes 2–3 m thick each are controlled by sequence cycles and sedimentary facies changes,and were mainly formed in the tidal flat environment during the depositional stages of the Ma56 and Ma55 sub-members.The microbial biostrome in the Ma55 sub-member occurring near the carbonate-evaporite transition interface in the early stage of the transgression is distributed mainly in the Mizhi subsag in the eastern part of the basin;the microbial biostrome in the Ma56 sub-member turns up near the carbonate-evoporite transition zone in ring shape in the east of the central uplift.The ancient landform had noticeable control on the distribution of microbial mounds.The microbial mounds or mound-shoal complexes developing mainly during the de-positional stages of Ma57_Ma510 sub-members are about 15–25 m thick in single layer and distributed largely in the Wushenqi-Jingbian paleouplift.The development model of the microbial carbonate rocks shows that the carbonate-evaporite lithologic transition zone and the Wushenqi-Jingbian paleouplift are favorable exploration zones of microbial carbonates in the Ordovician middle assemblages.

关键词： Ordos Basin Ordovician Majiagou Formation microbial carbonates stromatolite thrombolite oncolite deposi-tional model

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未来学校治理的关键与实践路径研究

现代教育科学 2024年第3期 8-14页

作者：杨晓莹黄郑亮中国教育科学研究院北京100088 工信部国际经济技术合作中心北京100804

管理的扁平化、教育模式的灵活化、人才培养的个性化以及学校空间的开放化等特征决定了未来学校建设的前瞻性与挑战性。基于这些治理特征,我国未来学校治理的关键在于治理主体的角色嬗变、制度的优化与完善、体现以人为本的特征以及技... 详细信息

管理的扁平化、教育模式的灵活化、人才培养的个性化以及学校空间的开放化等特征决定了未来学校建设的前瞻性与挑战性。基于这些治理特征,我国未来学校治理的关键在于治理主体的角色嬗变、制度的优化与完善、体现以人为本的特征以及技术的更迭与完善等方面。推动未来学校建设人人有责,应从提升多主体治理能力、增强多主体间的交流互动、完善未来学校制度建设以及探讨未来学校治理标准等方面予以展开。

关键词：未来学校治理特征治理能力主体交流制度建设

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FRP筋模块化夹片锚具设计及试验研究

建筑结构 2024年第3期54卷 39-43,70页

作者：肖开乾何林严政梁白石黄金武汉市市政建设集团有限公司武汉430056 南通装配式建筑与智能结构研究院南通226010 智性纤维复合加固南通有限公司南通226010

纤维增强复合即FRP材料属于各向异性材料,需要针对FRP的特性开发新的锚固系统。与传统FRP锚固方式不同,FRP筋模块化夹片锚具是将FRP筋、多孔切片铝套以及夹片作为一个标准模块,并将其压入锚杯的模块安装孔内。根据实际工况,在锚杯上增... 详细信息

纤维增强复合即FRP材料属于各向异性材料,需要针对FRP的特性开发新的锚固系统。与传统FRP锚固方式不同,FRP筋模块化夹片锚具是将FRP筋、多孔切片铝套以及夹片作为一个标准模块,并将其压入锚杯的模块安装孔内。根据实际工况,在锚杯上增加或减少模块安装孔的数量,从而达到拉索的使用要求。利用ANSYS Workbench有限元软件,对模块化锚具的内锥倾角、夹片与锚杯的角度差、锚固长度、FRP筋材间距、夹片预紧力等参数进行分析,提出了一种新型模块化锚固形式,并通过试验的方法来测试模块化夹片锚具的锚固性能。结果表明,采用模块化夹片锚具对FRP筋进行锚固的方法是可靠的,本文开发的模块化夹片式锚具的锚固效率超过90%,有利于锚固设计,降低成本。

关键词：纤维增强复合材料桥梁拉索模块化夹片锚具锚固效率

Effect of Hydrothermal Treatment on Suppressing Coking of ZSM-5 Zeolite during Methanol-to-Propylene Reaction

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China Petroleum Processing & Petrochemical Technology 2016年第2期18卷 7-13页

作者： Jiang Binbo Zhou Bingjie Yan Lixia Wei Lingze Xu Caixia Liao Zuwei Huang Zhengliang Wang Jingdai Yang Yongrong State Key Laboratory of Chemical Engineering Department of Chemical and Biochemical EngineeringZhejiang University

Fresh ZSM-5 zeolite catalysts were pretreated at 460 ℃and 500 ℃with various cumulative amount of water feed(CAWF) in a fixed bed reactor. The catalytic process was carried out under the following conditions: a temperature of 480 ℃; a methanol WHSV of 3 h-1; a methanol partial pressure of 30 k Pa; and a time on stream of 12 h, 24 h and 48 h, respectively. The BET parameters of catalysts and diffusion coefficients of toluene showed that there were two types of mesopores generated under different hydrothermal conditions. Mild temperature and moderate CAWF conditions led to external open mesopores which could be entered from the external surface of the zeolite, while a high temperature or a high CAWF condition resulted in the generation of macropores or internal isolated mesopores, which were occluded in the microporous matrix. The TGA results showed that catalyst with external open mesopores had good ability to resist coke accumulation and good performance on propylene selectivity, while the internal isolated mesopores did no contribute to the increased diffusivity of reactants and products.

关键词： methanol to propylene (MTP) hydrothermal treatment ZSM-5 coking mesopores diffusion

节点约束对单面连接角钢受压承载力影响试验研究

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建筑钢结构进展 2024年第2期26卷 24-33页

作者：鄢秀庆黄兴李正良何松洋刘翔云刘红军中国电力工程顾问集团西南电力设计院有限公司成都610056 重庆大学土木工程学院重庆400045 重庆大学山地城镇建设与新技术教育部重点实验室重庆400045

为了研究节点约束对单面连接角钢受压承载力的影响,设计了一种弹簧支座刀口铰,通过试验研究了120根等边角钢的偏心受压稳定承载力。分析了其最小轴、平行轴布置时的破坏模式、承载力及变形形态,研究了不同节点约束、构造形式对其承载力... 详细信息

为了研究节点约束对单面连接角钢受压承载力的影响,设计了一种弹簧支座刀口铰,通过试验研究了120根等边角钢的偏心受压稳定承载力。分析了其最小轴、平行轴布置时的破坏模式、承载力及变形形态,研究了不同节点约束、构造形式对其承载力的影响,并与国内规范进行了比较。研究结果表明:最小轴布置时,构件的失效模式为弯曲失稳,旋转轴介于最小轴和平行轴之间;平行轴布置时,构件失效模式为绕与刀口铰平行的主轴的弯曲失稳;构件长细比小于120时,其承载力主要受偏心控制,偏心越大,承载力越低;构件长细比大于120时,其承载力主要受约束刚度控制,约束刚度越大,承载力越高;采用A、C类连接时,在不同长细比下二者各具优势,但采用B类连接时构件的承载力始终低于采用A、C类连接时的承载力;与规范的对比表明,规范GB 50017—2017和DL/T 5486—2020均未考虑节点构造形式对斜材受压承载力的影响,计算结果存在一定的局限性,研究结论对于工程设计具有一定的指导意义。

关键词：输电塔节点约束节点构造形式偏心受压稳定承载力

鄂尔多斯盆地西缘中-上奥陶统烃源岩的形成环境、成烃生物及岩矿特征

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地质科学 2024年第3期59卷 696-711页

作者：包洪平黄正良郭玮王前平井向辉王刚刘建平中国石油长庆油田分公司勘探开发研究院低渗透油气田勘探开发国家工程实验室中国石油长庆油田分公司勘探事业部

鄂尔多斯盆地西南缘奥陶系发育与盆地本部奥陶系沉积特征截然不同的沉积层，其中西缘的中-上奥陶统烃源岩发育较好的海相烃源岩层。近期，通过对该套烃源岩形成的构造—沉积环境、成烃生物特征及烃源岩层岩矿特征等方面的分析，表明有... 详细信息

鄂尔多斯盆地西南缘奥陶系发育与盆地本部奥陶系沉积特征截然不同的沉积层，其中西缘的中-上奥陶统烃源岩发育较好的海相烃源岩层。近期，通过对该套烃源岩形成的构造—沉积环境、成烃生物特征及烃源岩层岩矿特征等方面的分析，表明有利烃源岩的发育受多种因素的控制，其分布具有一定的规律性：1）盆地中-上奥陶统主力烃源岩主要形成于沉积水体不断加深的构造沉积背景，其中沉积水体能量较弱，陆源碎屑注入相对较慢的半深水斜坡环境最有利于富有机质烃源岩发育；2）西南缘奥陶纪虽然生物类型多样，种群繁盛，但能形成重要烃源岩层的母源生物（生烃母质）却多以浮游生物、疑源类（微体藻类）及蓝细菌为主，相对还原的介质环境和适宜的沉积埋藏速率对有机质的有效保存也起重要的控制作用；3) X-衍射物相分析及扫描电镜等微观研究显示，主力烃源层段所谓“泥页岩层”的造岩矿物类型仍以石英、长石类为主，次为伊利石类黏土矿物与碳酸盐矿物，少量黄铁矿等；黏土矿物及黄铁矿含量与有机质丰度关系密切。

关键词：鄂尔多斯西缘奥陶系烃源岩成烃生物乌拉力克组岩矿特征

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肥胖影响慢性疼痛及分子机制研究进展

国际麻醉学与复苏杂志 2024年第4期45卷 429-433页

作者：张笑黄瑜琳马正良南京大学医学院附属鼓楼医院麻醉科南京210008 南京大学附属鼓楼医院麻醉科南京210008

肥胖与慢性疼痛是突出的全球健康问题。临床研究表明,慢性疼痛的发病率在肥胖人群中显著升高;动物实验表明,肥胖增加疼痛敏感性,但具体作用机制尚未见阐明。文章从炎症、免疫、神经内分泌、肠道微生物、信号分子及通路等方面对近年来肥... 详细信息

肥胖与慢性疼痛是突出的全球健康问题。临床研究表明,慢性疼痛的发病率在肥胖人群中显著升高;动物实验表明,肥胖增加疼痛敏感性,但具体作用机制尚未见阐明。文章从炎症、免疫、神经内分泌、肠道微生物、信号分子及通路等方面对近年来肥胖影响慢性疼痛的作用机制研究进行阐述,旨在优化临床肥胖患者疼痛防治策略,并为进一步研究提供思路。

关键词：肥胖慢性疼痛痛觉过敏分子机制