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Green Chemical Engineering 2023年第3期4卷 338-345页

作者： Weizhong Zheng Jialei Sha weizhen sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai200237China

Benzene alkylation catalyzed by immobilized ionic liquids(ILs)on solid carriers is considered as a heterogeneous reaction,in which the interfacial properties play an important ***,the interfacial characteristics between benzene/1-dodecene mixture and immobilized chloroaluminate ILs with different alkyl chain length on the silica substrate were investigated by molecular dynamics *** grafted ILs can obviously promote the enrichment of benzene near the interface,leading to a higher ratio of benzene to dodecene,and the interfacial width increases slightly with increased alkyl chain of grafted *** the same time,the grafted cations can also enhance the benzene diffusion and suppress the dodecene diffusion at the interface,which probably helps to inhibit the inactivation of *** work provides deeply insights into the rational design of novel immo-bilized ILs catalysts for the benzene alkylation.

关键词： Benzene alkylation Interfacial property Molecular dynamics simulation Immobilized ionic liquids

Understanding the interfacial behaviors of benzene alkylation with butene using chloroaluminate ionic liquid catalyst: A molecular dynamics simulation

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Chinese Journal of Chemical Engineering 2023年第2期54卷 44-52页

作者： Jialei Sha Chenyi Liu Zhihong Ma Weizhong Zheng weizhen sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry&Chemical Engineering Xinjiang UniversityUrumqi 830046China

To better understand the benzene alkylation with chloroaluminate ionic liquids(ILs) as catalyst, the interfacial properties between the benzene/butene binary reactants and chloroaluminate ILs with varying cation alkyl chain length and different anions were investigated using molecular dynamics(MD) simulations. The results indicate that ILs can obviously improve the interfacial width, solubility and diffusion of reactants compared to H_(2)SO_(4). The longer alkyl chains of cations present a density enrichment at the interface and protrude into the binary reactants phase. Furthermore, the ILs consisting of 1-octyl-3-methylimidazolium cations([Omim]^(+)) and the stronger acidity heptachlorodialuminate anions([Al_(2)Cl_(7)]^(-)) are more beneficial to promote the interfacial width and facilitate the dissolution and diffusion of benzene in both the IL bulk and the interfacial region in comparison to the ones with shorter alkyl chains cations and weaker acidity anions. The information gives us a better guideline for the design of ILs for benzene alkylation.

关键词： Benzene alkylation Interfacial behaviors Ionic liquids Molecular dynamics simulation

Response of monsoon vari-ability in Himalayas to global warming

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Chinese Science Bulletin 2002年第21期47卷 1842-1845页

作者： DUAN Keqin YAO Tandong PU Jianchen sun weizhen Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

Reconstructed annual net accumulation from the Dasuopu ice core recovered in Himalayas, with a good correlation to Indian monsoon, reflects a major precipitation trend in central Himalayas. The Dasuopu accumulation (DSP An) also shows a strong correlation to the Northern Hemispheric temperature. Generally, as the Northern Hemispheric temperature increases by 0.1 K, the accumulation decreases by about 90 mm and vise versa. Under the condition of global warming, especially since 1920, the Northern Hemispheric mean temperature has increased by about 0.5 K, whereas accumulation in Dasuopu ice core has decreased by about 450 mm. According to the relationship between accumulation and temperature, a scenario prediction of monsoon rainfall in central Himalayas is made.

关键词： Dasuopu ice core accumulation global warming.

Experiments and kinetic modeling of the sorbitol dehydration to isosorbide catalyzed by sulfuric acid under conditions of non-constant volume

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Chinese Journal of Chemical Engineering 2024年第9期73卷 281-289页

作者： Dechang Cheng Zhihong Ma Ziyang Liu Xiaohui Liu Tao Liu weizhen sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Functional Materials Chemistry Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Isosorbide is a novel bio-based material derived as a secondary dehydration product of *** work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant ***,the effects of stirring rate,catalyst dosage,reaction temperature,and reaction time on the dehydration reaction of sorbitol were *** yield of isosorbide up to 77.13%was obtained after 1.5 h of reaction time under conditions of 2 kPa,1.0%(mass)catalyst dosage,and 413.15 *** on the sorbitol dehydration reaction mechanism and a simplified reaction network,a kinetic model was developed in this work.A good agreement was accomplished between kinetic modeling and experiments between 393.15 and 423.15 *** fitting results indicate that side reactions with higher activation energies are more affected by reaction temperatures,and the main side reaction that influences the selectivity of isosorbide is the oligomerization reaction among the primary dehydration products of *** model fitting of the catalyst amounts effect shows that the effective concentration of sulfuric acid would be reduced with the increase of dosage due to the molecular agglomeration ***,the kinetic experiments and modeling results obtained in this work will be helpful to the design and optimization of the industrial sorbitol dehydration process.

关键词： Isosorbide Sorbitol dehydration Non-constant volume Kinetic modeling

Clustering Analysis of Black-start Decision-making with a Large Group of Decision-makers

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电力系统自动化 2012年第8期36卷 154-160页

作者： Liu, Weijia Lin, Zhenzhi Wen, Fushuan Xue, Yusheng Dai, Yan sun, weizhen Wang, Chao Zhejiang University Hangzhou 310027 China State Grid Electric Power Research Institute Nanjing 210003 China Zhejiang Electric Power Dispatch and Communication Center Hangzhou 310007 China

The optimization of black-start decision-making plays an important role in the rapid restoration of a power system after a major failure/*** the introduction of the concept of smart grids and the development of real-time communication networks,the black-start decision-makers are no longer limited to only one or a few power system experts such as dispatchers,but rather a large group of professional people in *** overall behaviors of a large decision-making group of decision-makers/experts are more complicated and ***,the existing methods for black-start decision-making cannot handle the situations with a large group of *** this background,a clustering algorithm is presented to optimize the black-start decision-making problem with a large group of *** decision-making preferences are obtained by clustering analysis,and the final black-start decision-making results are achieved by combining the weights of black-start indexes and the preferences of the decision-making *** effectiveness of the proposed method is validated by a practical *** work extends the black-start decision-making problem to situations with a large group of decision-makers.

关键词：决策者聚类分析黑启动大集实时通信网络决策问题电力系统电源系统

A separation column for liquid mixture based on phase transform:Experiment and simulation

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Chinese Journal of Chemical Engineering 2024年第10期74卷 144-153页

作者： Mengjie Liu Weiqun Gao Kexin Yan Yudong Li Bihong Li Jiating Zhang weizhen sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

The concentric internally heat-integrated distillation column(HIDi C) has advantages of low energy consumption and high thermodynamic efficiency. However, its drawbacks of limited heat transfer area,complex internal structure, and large number of control parameters hinder its widespread industrial applications. To solve these challenges, in this work a novel sleeve-like concentric heat-integrated separation column, namely temperature-controlled phase change column(TCPC), was developed to separate liquid mixtures in a more effective and energy-saving way with reflux section being moved and trays being replaced with spiral corrugation blades. The comprehensive performances of TCPC in ethanol-water system was firstly evaluated by experiments. The results showed that TCPC performs well in ethanol-water separation due to the internal spiral corrugation significantly reducing the vapor-liquid contact in separation section. Meanwhile, compared to the concentric HIDi C, TCPC has a higher total heat transfer coefficient due to the larger heat transfer area. Computational fluid dynamics simulation reveals the internal design of TCPC inducing secondary vortices of the vapor, enhancing condensation heat transfer and separation efficiency. Further, increasing the mass flow rate within a certain range would enhance the comprehensive performance factor and lead to more effective separation.

关键词： Temperature-controlled phase change column Spiral corrugation blade Heat integration Computational fluid dynamics

Distribution of δ^(18)O in surface snow along a transect from Zhongshan Station to Dome A,East Antarctica

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Chinese Science Bulletin 2010年第24期55卷 2709-2714页

作者： DING MingHu XIAO CunDe JIN Bo REN JiaWen QIN DaHe sun weizhen Division of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Chinese Arctic and Antarctic Administration Beijing 100860 China

Surface snow samples were collected during the 14th(1997/1998)and 24th(2007/2008)Chinese National Antarctica Research Expeditions along a transect from Zhongshan Station to Dome *** stable oxygen isotope ratios of these samples were measured to investigate their relationships with temperature and geographical parameters(latitude,longitude,altitude and distance to the coast).The results reveal a strong positive correlation(R=0.945)betweenδ18O and mean annual temperature,with a gradient of 0.84‰°C-1,which is a little higher than that in Terre Adelie *** analyses also show that theδ18O of surface snow is strongly correlated with distance to the coast(R=0.942),latitude(R=0.942),and altitude(R=0.941).But no significant correlation was found betweenδ18O and longitude in study *** should be the most important factor influencing the δ18O distribution because of distinctive ***δ18O-altitude and T-altitude gradients along this transect are determined to be-1.1‰/100 m and 1.31°C/100 m,respectively.

关键词：东南极洲中山站断面积雪地表冰穹海拔高度同位素比值

Source and environmental significance of oxalate in Laohugou Glacier No. 12, Qilian Mountains, Western China

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Research in Cold and Arid Regions 2018年第2期10卷 126-133页

作者： weizhen sun XiaoQing Cui GuangMing Yu State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences School of Resources and Environment Sciences Anqing Normal University

Retrieval of oxalate from snow and ice provides information on past environmental changes. In recent years, records of organic acids in middle-and low-latitude glaciers have attracted the attention of researchers globally. In this study, we analyzed oxalates in an ice core from Laohugou Glacier No. 12 on the Qilian Mountains at an elevation of 5,040 m a.s.l. in2006. Average oxalate concentration was 18.5±2.4 ng/g over the prior 46 years. Oxalate values showed a significantly increasing trend since 1985. From 1985 to 1995, oxalate concentrations had large fluctuations, peaking in about 1987 and exhibiting a slightly decreasing trend since 1995. The result shows that the abrupt increase of oxalate concentration in the ice core since the mid-1980 s reflects atmospheric environmental pollution by human and industrial activities.

关键词： glacier ice core environment Qilian Mountains

Low frequency oscillation characteristics of East China Power Grid after commissioning of Huai-Hu ultra-high voltage alternating current project

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Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 332-340页

作者： Chao WANG Yang LV Hongyang HUANG Jing ZHANG Jihong LI Yingyi LI weizhen sun Yong CHANG State Grid Zhejiang Electric Power Company Hangzhou 310007China State Grid Jilin Electric Power Company Changchun 130000China State Grid Operation Company Beijing 100052China

The low frequency oscillation characteristics of East China Power Grid after commissioning of the first ultra-high voltage alternating current(UHVAC)project-the Huai-Hu UHVAC project are *** low frequency oscillation cases occurred in East China Power Grid in the past few years are reviewed and *** on the analysis of the different typical operation modes,the main low frequency oscillation modes in East China Power Grid in the early stages of development of ultra-high voltage(UHV)are summarized,and the impacts of the significant power grid maintenance on low frequency oscillation characteristics are ***,the oscillation mode of UHV generators to East China Power Grid is researched,and the importance of the power system stabilizator(PSS)is ***,the comparative analysis between the time domain and the frequency domain is carried out,and the influences of the governing system on low frequency oscillation characteristics are ***,both the focus and the direction of low frequency oscillation research are presented.

关键词： Ultra-high voltage(UHV) Low frequency oscillation Forced oscillation Power system stabilizator(PSS) Governing system

Combined static mixers for high viscous fluids mixing

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Frontiers of Chemical Science and Engineering 2009年第1期3卷 93-96页

作者： Zhenhao XI weizhen sun Ling ZHAO Zhaoyan LIU State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Beijing Innovation Polymerization Technology Company Beijing 100050China

A new static mixer Cross-over-Disc has been invented to strip off the boundary layer and to make strong radial *** pressure drop of Cross-over-Disc is 12–26 times as large as that of empty pipe with equivalent diameter and *** mixing performance of Cross-over-Disc with 14 elements has been investigated in the viscosity range of 190–250 Pa·s by decoloration method,and the gray analysis of images shows that mixing inhomogeneity is about 7.5%and 9.4%for the mixing ratio of 5∶1 and 10∶1,***,mixing inhomogeneity for a combination of static mixing elements(four from Cross-over-Disc and three pairs from Sulzer-type)can be decreased to 2.1%–3.1%within a reasonable range of pressure drop.

关键词： static mixer Cross-over-Disc pressure drop mixing performance high viscousﬂuid