检索结果-内蒙古大学图书馆

An improved EMMS model for turbulent flow in pipe and its solution

Particuology 2023年第5期76卷 1-12页

作者： Lin Zhang Wen Lai Huang Jianhua Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

Based on the existing energy-minimization multi-scale(EMMS)model for turbulent flow in pipe,an improved version is proposed,in which not only a new radial velocity distribution is introduced but also the quantification of total dissipation over the cross-section of pipe is improved for the dominant mechanism of fully turbulent flow in *** four dynamic equality constraints and some other constraints are constructed but there are five parameters involved,leading to one free variable *** the compromise in competition between dominant mechanisms for laminar and fully turbulent flow in pipe respectively,the above four constructed dynamic equality constraints can be ***,the cases for turbulent flow in pipe with low,moderate and high Reynolds number are simulated by the improved EMMS *** numerical results show that the model can obtain reasonable results which agree well with the data computed by the direct numerical simulation and those obtained by *** illustrates that the improved EMMS model for turbulent flow in pipe is reasonable and the compromise in competition between dominant mechanisms is indeed a universal governing principle hidden in complex ***,one more EMMS model for a complex system is offered,pro-moting the further development of mesoscience.

关键词： Mesoscience EMMS Compromise in competition Dominant mechanism Turbulent flow in pipe

来源：评论

学校读者我要写书评

暂无评论

Coupling of an amine-based carbon capture unit to a municipal solid waste incineration plant – an analysis of the dynamics

引用

Applied Thermal engineering 2025年 275卷

作者： Hüting, Florian Wieland, Christoph University of Duisburg-Essen Chair of Energy Process Engineering and Energy Systems North Rhine-Westphalia Essen Germany Gas- und Wärme-Institut Essen e.V. and University of Duisburg-Essen Chair of Energy Process Engineering and Energy Systems North Rhine-Westphalia Essen Germany

This study investigates the integration of an amine-based CO2 capture system with a municipal solid waste incineration (MSWI) plant in Germany, focusing on mitigating CO2 emissions from flue gas. Using operational dat... 详细信息

This study investigates the integration of an amine-based CO₂ capture system with a municipal solid waste incineration (MSWI) plant in Germany, focusing on mitigating CO₂ emissions from flue gas. Using operational data from the MSWI plant, the study analyzes the impact of highly dynamic and inhomogeneous flue gas composition on carbon capture performance. A steady-state simulation model of a carbon capture plant was developed in Aspen Plus® to optimize operational conditions and evaluate the effects of acidic components on system performance. Results indicate that while a direct contact cooler (DCC) with water reduces SO₂ and NO_x concentrations modestly, better removal rates are achieved by lowering flue gas temperatures or increasing operational pressure. Only 11.4% of the solvent degrades oxidative after 8000 operating hours because of the prior flue gas cleaning in the MSWI plant. At 1 bar pressure and 140 °C flue gas temperature, the DCC only reduced the degradation rate by 3.3%. A dynamic simulation model in Aspen Dynamics® assesses system response to variable flue gas conditions. Significant load increases reduce the CO₂ capture rate temporarily to 61%. An optimization of the dynamic simulation model is carried out, which substantially improves performance. Additional implemented feed-forward control for solvent management further enhances response times and minimizes overshoot. The integration of model predictive control was less effective due to high dynamics of the flue gas composition and flowrate. Energy optimization reveals synergies between the MSWI plant and CO₂ capture system, identifying opportunities for heat recovery and reduced energy demand. The integrated simulations provide insights into optimizing system integration and operational strategies for economic and ecological viability. © 2025 The Author(s)

关键词： Aspen Degradation Dynamics MEA Optimization PCC Waste

来源：评论

学校读者我要写书评

暂无评论

Unveiling the photocatalytic activity of Cu/Fe₂O₃@gC₃N₄ nanosheet as an efficient fenton-like catalyst for reactive blue 19 removal: Optimization and kinetics studies

Hybrid Advances

引用

Hybrid Advances 2025年 9卷

作者： Tchuifon Tchuifon, Donald Raoul Fotsop, Cyrille Ghislain Mafo, Sandrale Grace Mokue Solefack Feudjio, Frank Dorinel Dongmo, Sanchez Dave Mouafo Ndifor-Angwafor, Nche George Department of Process Engineering Laboratory of Energy Materials Modeling and Method National Higher Polytechnic School of Douala University of Douala Douala Cameroon Institute of Chemistry Faculty of Process and Systems Engineering Universität Platz 2 Magdeburg 39106 Germany Department of Chemistry Research Unit of Noxious Chemistry and Environmental Engineering Faculty of Science University of Dschang P.O. Box 67 Dschang Cameroon Laboratory of Applied Physical and Analytical Chemistry Department of Inorganic Chemistry Faculty of Science University of Yaoundé 1 P.O. Box 812 Yaoundé Cameroon

In this work, a Cu/Fe2O3@g-C3N4 nanocomposite was synthesed using the thermal decomposition of urea as a carbon and nitrogen precursor to remove the reactive blue 19 (RB-19) in aqueous solution by the Fenton process. ... 详细信息

In this work, a Cu/Fe₂O₃@g-C₃N₄ nanocomposite was synthesed using the thermal decomposition of urea as a carbon and nitrogen precursor to remove the reactive blue 19 (RB-19) in aqueous solution by the Fenton process. The obtained material was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray (EDX) analysis and EDX-mapping techniques. The results obtained confirmed that the material was indeed doped with Cu and Fe with a crystalline structure. A central composite design was used to optimize the degradation factors. The optimal conditions were obtained at a pH of 3, with a catalyst mass of 75 mg, an initial pollutant concentration of 100 mg/L and a H₂O₂ concentration of 1 mol/L, with a respective degradation percentage of 96 %. The reusability of the catalyst allowed to observe that it retains its catalytic activity with a degradation rate higher than 84 % after five cycles. The degradation kinetics of RB-19 allowed to have R² values close to 1 for the influence of pH. The pseudo-first and second order kinetic models were studied, with rate constants ranging from 1.7x10⁻³ to 5.3x10⁻³ min⁻¹ and 3.6x10⁻⁶ to 7.3x10⁻⁴ L/***, respectively for a pH. According to this study, it was confirmed that the H₂O₂/catalyst (Cu/Fe₂O₃@g-C₃N₄) nanocomposite could be an effective and resistant means to treat wastewater containing RB-19. © 2025 The Authors

关键词： Cu/Fe2O3@g-C3N4 Fenton process Reactive blue 19 Wastewater treatment

来源：评论

学校读者我要写书评

暂无评论

THE APPLICATION OF A NOVEL CHEMICAL TREATMENT PROGRAM TO MITIGATE SCALING AND FOULING IN REVERSE-OSMOSIS UNITS

引用

DESALINATION 1994年第1-3期96卷 71-79页

作者： JAFFER, AE Process and Control Systems Department Saudi Arabian Oil Co. PO Box 5032 Dhahran Saudi Arabia

The principal cause of reverse osmosis (RO) system failures is membrane fouling, which results from the accumulation of water-formed or water-borne deposits that impede the flow of fluid and increase the pressure differential across a membrane. Anti-scalant chemicals have been used for many years in RO units to minimize fouling, prevent scaling, and improve RO plant performance. The conventional method for controlling scale formation on membranes involves addition of sulfuric acid and a scale inhibitor to the feed water. However, the desire for improved chemical treatment programs to prevent scaling and fouling in RO units brought Saudi Aramco and Specialty Chemical Suppliers together. The challenge to produce a chemical treatment program that was simpler, safer, and more economical than the traditional sulfuric acid treatment and a scale inhibitor was identified as a mutual goal. This paper presents the results of intensive trials conducted by Saudi Aramco and the chemical suppliers to evaluate commercially available chemical formulations.

关键词： Chemical water treatment

来源：评论

学校读者我要写书评

暂无评论

Formation of efficient dye-sensitized solar cells by introducing an interfacial layer of hierarchically ordered macro-mesoporous TiO_2 film

引用

Science China Chemistry 2011年第6期54卷 930-935页

作者： HALPERT Jonathan E State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences

Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ordered structure and a large specific surface area, which was applied as an interfacial layer between the nanocrystalline TiO2 film (P25-TiO2) and FTO electrode in the dye-sensitized solar cell (DSSC). The introduction of a Ti-Ma-Me interfacial layer increased the shortcircuit current density (Jsc) from 7.49 to 10.65 mA/cm2 and the open-circuit voltage (Voc) from 0.65 to 0.70 V as the result of its improved light harvesting efficiency by allowing for the high roughness factor and enhanced multiple internal reflection or scattering as well as reducing the back-transport reaction by blocking direct contact between the electrolyte and FTO electrode. Therefore, the photovoltaic conversion efficiency (η) was improved by 83% from 3.04% to 5.55%, as compared to a device using a bare P25 TiO2 photoanode.

关键词： dye-sensitized solar cells hierarchical ordered macro-mesoporous photoanode

来源：评论

学校读者我要写书评

暂无评论

DESIGN OF PROCEDURAL controlLERS FOR CHEMICAL processES

引用

COMPUTERS & CHEMICAL engineering 1995年第Sup1期19卷 S381-S386页

作者： SANCHEZ, A MACCHIETTO, S Centre for Process Systems Engineering Imperial College London SW7 2BY UK

A four step method is presented for the formal specification and synthesis of procedural controllers. These controllers are used in the process industries for safety and alarm operations, interlocking, batch sequencing, etc. The procedural controller is based on a process model that takes the form of a labelled finite state machine, termed a-machine. Desired process behaviour specifications are constructed using Predicate (PL) and Linear Temporal Logic (LTL) formalisms. The resulting controller structure can then be translated into a target sequential control language for implementation. The method is demonstrated with a small example.

关键词： PROCEDURAL control DISCRETE EVENT systems process AUTOMATION FORMAL METHODS

来源：评论

学校读者我要写书评

暂无评论

Mesoscale structures and mechanisms in ionic liquids

引用

Particuology 2020年第1期18卷 55-64页

作者： Xiaomin Liu Xiaoqian Yao Yanlei Wang Suojiang Zhang School of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsKey Laboratory of Green Process and EngineeringInstitute of process EngineeringChinese Academy of SciencesBeijing 100190China

Ionic liquids(ILs)have attracted intensive attention and have been used widely in many applications because of their diversified properties,which are caused by the special structure of the *** clusters are one of the typical structures that exist widely in the IL *** are stable under certain conditions and change under other *** clusters are a typical mesoscale phenomenon in *** this review,we summarize our recent progress related to ionic clusters,including the ionic-cluster structure,changing mechanisms,and their effect on the physicochemical *** cluster investigation based on mesoscience is very important,will provide new insight into the structures and properties of ILs,and will boost further exploration of IL applications.

关键词： Ionic liquid Mesoscale structure Ionic cluster

来源：评论

学校读者我要写书评

暂无评论

control System Design for Multivariable Nonlinear systems Guaranteeing Good Performance Over Wide Operating Ranges

引用

IFAC-PapersOnLine 2017年第2期50卷 245-246页

作者： Taiwo, O. Adeyemo, S.O. Sorinolu, A. Process Systems Engineering Laboratory Obafemi Awolowo University Ile-Ife Nigeria

It is sometimes necessary that a process plant operates over a wide range while satisfying desired performance and stipulated constraints. This paper proposes a method based on computing a mean (nominal) plant, uncertainty weight based on the deviations of the extreme plants from the mean plant and performance weights capturing desired performance. The work considers simple multi-loop and centralized controllers and their parameter determination using optimization. In order to expeditiously compute the centralized controller parameters, its initial parameters are determined using the parameterization based on the multivariable internal model controller (MIMC) of the p/q Pade approximant of the mean plant. The order of magnitude of the MIMC filter is determined by noting the magnitude of a suitably computed multiloop controller which, at least, stabilizes the closed loop system. In this work, desired metrics for the closed loop system include robust performance, minimization of the closed loop system integral of squared error (ISE) and limiting the maximum controller outputs over the full operating range. It is demonstrated that the new method facilitates the computation of simple centralized controllers yielding closed loop systems with favorable characteristics. © 2017

关键词： Closed loop systems controllers Integrated control Nonlinear systems Optimization Centralized controllers Integral of squared errors Internal model controllers Multi loop controllers Multivariable nonlinear systems Parameter determination Robust performance uncertainty

来源：评论

学校读者我要写书评

暂无评论

Numerical analysis of residence time distribution of solids in a bubbling fluidized bed based on the modified structure-based drag model

引用

Particuology 2017年第3期15卷 30-38页

作者： Zheng Zou Yunlong Zhao Hu Zhao Hongzhong Li Qingshan Zhu Zhaohui Xie Yingbo Li State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Belting 100049 China Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Belting 100190 China

The residence time distribution （RTD） of solids and the fluidized structure of a bubbling fluidized bed were investigated numerically using computational fluid dynamics simulations coupled with the modified structure-based drag model. A general comparison of the simulated results with theoretical values shows reasonable agreement. As the mean residence time is increased, the RTD initial peak intensity decreases and the RTD curve tail extends farther. Numerous small peaks on the RTD curve are induced by the back- mixing and aggregation of particles, which attests to the non-uniform flow structure of the bubbling fluidized bed. The low value of t50 results in poor contact between phases, and the complete exit age of the overflow particles is much longer for back-mixed solids and those caught in dead regions. The formation of a gulf-stream flow and back-mixing for solids induces an even wider spread of RTD.

关键词： FluidizationResidence time distribution Bubbling fiuidized bed Modified structure-based drag mode Computational fluid dynamics CFD

来源：评论

学校读者我要写书评

暂无评论

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

引用

Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li Rui-Rui Zhang Ke-Xin Li Shuang Wei Yu-Mei Liu Rui-Xia Liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：