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Fluidization characteristics of different sizes of quartz particles in the fluidized bed

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Petroleum Science 2016年第3期13卷 584-591页

作者： zi-jian Wang Jun Tang Chun-Xi Lu State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)

Fluidization characteristics of quartz particles with different sizes are experimentally investigated in a fluidized bed with an inner diameter of 300 mm and height of 8250 *** show that the average solid holdup increases with the increase in superficial gas velocity and the decrease in initial solid holdup in the dense zone of the fluidized *** average cross-sectional solid holdup decreases with increasing bed height and superficial gas *** bed expansion coefficient increases with the increase in superficial gas velocity and the decrease in solid *** of average solid holdup,average cross-sectional solid holdup and bed expansion coefficient are also established and *** correlations can provide guidelines for better understanding of the fluidization characteristics.

关键词： Fluidization characteristic Solid holdup Axial average section solid holdup Bed expansion coefficient

Characteristics of Deoxidation and Desulfurization during LF Refining Al-killed Steel by Highly Basic and Low Oxidizing Slag

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Journal of Iron and Steel Research International 2014年第2期21卷 166-173页

作者： Jing guO Shu-sen CHENG zi-jian CHENG State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology of Beijing Jiuquan Iron and Steel (Group) Co. Ltd.

Steel and slag samples were taken at the start and the end of LF refining for steel plate cold common （SPCC）, in the compact strip production （CSP） process, and at the same time, the temperature and oxygen activity a[o] were measured by using an oxygen sensor. Furthermore, inclusions in steel samples were monitored by scanning electron microscopy （SEM） combined with energy dispersive spectroscopy （EDS）. It was confirmed that a [o] in liq- uid steel was in equilibrium with inclusion rather than with top slag during LF refining. Desulfurization was related to deoxidation since a[o] at slag-steel interface was clarified to be very close to that in liquid steel under the specific con- dition in LF with intense stirring by argon blowing and refined by highly basic low oxidizing slag for Al-killed steel. Sulfur partition ratio （Ls） was very sensitive to a[o]. Since a[o] increased rapidly with temperature rise, it not only offset promotion to desulfurization reaction with temperature rise but decreased Ls. For Al-killed steel, ***- tion of Al2O3 for lowering the activity of Al2O3 in inclusion was believed to be favorable for both deoxidation and desulfurization during LF refining.

关键词： deoxidation desulfurization inclusion sulfur partition ratio LF refining

On the correction of the boundary deficiency in SPH for the frictional contact simulation

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Science China(Technological Sciences) 2014年第1期57卷 86-100页

作者： WANG jian HUA Hui gu ChongShi National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

Smoothed particle hydrodynamics(SPH)is a mesh-free method which is powerful for large deformation computation of ***,the algorithm for the simulation of frictional contact which is common in geotechnical engineering is still quite immature due to the boundary *** this study,the cause of boundary deficiency in the SPH simulation for frictional contact is ***,based on mathematical derivation,the method to correct boundary deficiency related to frictional contact is discussed theoretically,where the frictional contact algorithm is established by dividing the computational domain into several subdomains according to the existing contact boundaries and by using contact forces as bridges of these subdomains to fulfil problem solving,and the value of correction coefficient is obtained by comparing the SPH outcome of the contact particles with that calculated through Newton’s second law of *** the same time,from the perspective of numerical computation,an optimized value for the correction coefficient is proposed,and a thorough investigation is performed on the cubic spline kernel function and quintic spline kernel function,whose correction coefficients are found to be 2.0 and[2.0,2.16],***,numerical tests are carried out to verify the proposed *** outcome of the study is helpful to providing theoretical support for the research of frictional contact simulation within the framework of SPH.

关键词： smoothed particle hydrodynamics (SPH) frictional contact boundary deficiency correction

Preparation of blast furnace burdens by composite agglomeration process: effect of distribution of magnetite and hematite concentrates in pelletized and matrix feed

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Journal of Iron and Steel Research International 2020年第12期27卷 1363-1371页

作者： Fo-quan gu Yuan-bo Zhang guang-hui Li Qiang Zhong Jun Luo zi-jian Su Ming-jun Rao Zhi-wei Peng Tao jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Effect of distribution of iron concentrates between pelletized and matrix feed on the preparation of blast furnace burdens from two different kinds of fine iron concentrates (magnetite and hematite) by composite agglomeration process (CAP) was explored. It was found that when the mass ratio of iron concentrate A (magnetite) to iron concentrate B (hematite) in the mixed feed was constant, the proportion of iron concentrate A in the pelletized and matrix feed significantly affected the quality of CAP products. Particularly, as the proportion of iron concentrate A in the pelletized feed increased from 0 to 100%, the yield decreased from 82.11% to 79.19% and the tumbler index decreased from 71.33% to 68.27%. The mineralization characterization results indicated that when 100% iron concentrate A was used as the pelletized feed, the crystallization styles of the outer layer and the inner layer of the pellet were different, and a lot of pores exist around hematite and magnetite phases in the pelletized part, with the weak connection of pelletized and matrix part, resulting in poor strength of agglomeration product.

关键词： Composite agglomeration process Sintering Fine iron concentrate Pelletized feed Blast furnace burden

Sensitivity of Sample for Simulation-Based Reliability Analysis Methods

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 331-357页

作者： Xiukai Yuan jian gu Shaolong Liu School of Aerospace and Engineering Xiamen UniversityXiamen361005China Institute for Risk and Reliability Leibniz Universitat HannoverHannoverGermany

In structural reliability analysis,simulation methods are widely *** statistical characteristics of failure probability estimate of these methods have been well *** this study,the sensitivities of the failure probability estimate and its statistical characteristics with regard to sample,called‘contribution indexes’,are proposed to measure the contribution of *** contribution indexes in four widely simulation methods,i.e.,Monte Carlo simulation(MCS),importance sampling(IS),line sampling(LS)and subset simulation(SS)are derived and *** proposed contribution indexes of sample can provide valuable information understanding the methods deeply,and enlighten potential improvement of *** is found that the main differences between these investigated methods lie in the contribution indexes of the safety samples,which are the main factors to the efficiency of the ***,numerical examples are used to validate these findings.

关键词： Reliability analysis Monte Carlo simulation importance sampling line sampling subset simulation

Convolution-based multi-scale envelope inversion

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Petroleum Science 2020年第2期17卷 352-362页

作者： Ding-Jin Liu jian-Ping Huang zi-Ying Wang Sinopec Geophysical Research Institute Nanjing 211103JiangsuChina China University of Petroleum(East China) Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology Qingdao 266571ShandongChina

Envelope inversion(El)is an efficient tool to mitigate the nonlinearity of conventional full waveform inversion(FWI)by utilizing the ultralow-frequency component in the seismic ***,the performance of envelope inversion depends on the frequency component and initial model to some *** improve the convergence ability and avoid the local minima issue,we propose a convolution-based envelope inversion method to update the low-wavenumber component of the velocity ***,the multi-scale inversion strategy(MCEI)is also incorporated to improve the inversion accuracy while guaranteeing the global *** success of this method relies on modifying the original envelope data to expand the overlap region between observed and modeled envelope data,which in turn expands the global minimum basin of misfit *** accurate low-wavenumber component of the velocity model provided by MCEI can be used as the migration model or an initial model for conventional *** numerical tests on simple layer model and complex BP 2004 model verify that the proposed method is more robust than El even when the initial model is coarse and the frequency component of data is high.

关键词： Full waveform inversion Multi-scale strategy Envelope inversion

The Synthesis and Characterization of High Molecular Weight Poly(phenylene sulfide/ether)

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Chinese Chemical Letters 2006年第10期17卷 1373-1376页

作者： Ai Qun gu Mei Ju XIE zi Li YU Institute of Materials Science ＆ Technology Analytical ＆ Testing Center Sichuan University Chengdu 610064

Poly（phenylene sulfide/ether）（PPSE） was synthesized from 4,4＇-dihydroxydiphenyl sulfide and 4,4＇-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR, ^1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed. PPSE had the same reflex indices as poly（p-phenylene sulfide）, an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively. The product was soluble in common organic solvents such as NMP, N, N＇-dimethylformamide, N, N＇-dimethylacetamide and 1,2-dichloroethane.

关键词： Poly(phenylene sulfide/ether) (PPSE) synthesis characterization.

Effect of Sequence Structure on Wetting Behaviors of Fluorinated Methacrylate Polymers Based on Perfluorohexylethyl Methacrylate and Stearyl Acrylate

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Chinese Journal of Polymer Science 2017年第9期35卷 1061-1072页

作者： zi-xu gu jun cheng ming-zu zhang jin-lin he 倪沛红 College of Chemistry Chemical Engineering and Materials Science State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis Soochow University Suzhou 215123 China

Due to the non-crystalline properties of short chain perfluoroalkyl groups, using short chain perfluoroalkyl to stabilize low surface free energy polymers has been a challenging task. In this study, we prepare a series of random copolymers poly（perfluorohexylethyl methacrylate）-co-poly（stearyl acrylate）（P13FMA-co-PSA） and block copolymers poly（perfluorohexylethyl methacrylate）-b-poly（stearyl acrylate）（P13FMA-b-PSA）, and systematically investigate the effects of the sequence structure and the content of 13FMA of the fluorinated copolymers on surface free energy and surface reorganization. Static/dynamic contact angle goniometry and water/oil repellency analyses demonstrate that the random polymer P13FMA-co-PSA could not achieve low surface free energy and low surface reorganization at the same time. In contrast, for the block copolymer P13FMA-b-PSA, both low surface free energy and low surface reorganization are acquired simultaneously. The results of X-ray photoelectron spectroscopy （XPS）, dynamic contact angle goniometry and differential scanning calorimetry （DSC） reveal the above-mentioned properties. The consecutive 13FMA segments improve the surface fluorine density, while the consecutive SA chains enhance the crystallinity of the SA segments, and further hinder the surface reorganization of the perfluoroalkyl groups. Therefore, P13FMA-b-PSA exhibits a higher utilization efficiency of fluorine atoms and a better structural stability than P13FMA-co-PSA.

关键词： Surface free energy Surface reorganization Perfluorohexylethyl methacrylate (13FMA) Stearyl acrylate (SA) Water/oil repellency

Synthesis of flexible inter-plant heat exchanger networks: A decomposition method considering intermedium fluid circles

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第11期75卷 62-73页

作者： Tao, Ran gu, Siwen Liu, Linlin Du, jian Dalian Univ Technol Sch Chem Engn Inst Proc Syst Engn Dalian 116023 Peoples R China Changzhou Inst Technol Sch Photoelect Engn Changzhou 213032 Peoples R China

The traditional methods for synthesizing flexible heat exchanger networks (HENs) are not directly applicable to inter-plant HEN challenges, primarily due to the spread of system uncertainty across plants via intermedium fluid circles. This complicates the synthesis process significantly. To tackle this issue, this study proposes a decomposed stepwise methodology to facilitate the flexible synthesis of the interplant HENs performing indirect heat integration. A decomposition strategy is proposed to divide the overall network into manageable sub-networks by dissecting the intermedium fluid circles. To address the variability in intermedium fluid temperatures, a temperature fluctuation analysis approach is developed and a heuristic rule is introduced to maintain the temperature feasibility of the intermedium fluids. To ensure adequate flexibility and cost-effectiveness of the designed networks, flexibility analysis and network retrofit steps are conducted through model-based optimization techniques. The efficacy of the method is demonstrated through two case studies, showing its potential in achieving the desired operational flexibility for inter-plant HENs. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Inter-plant heat exchanger networks (HENs) Indirect heat integration Flexible synthesis Flexible analysis Decomposition method