检索结果-南通市图书馆

Particuology 2013年第6期11卷 703-714页

作者： Xiaomin Chen Jiu Dai Zhenghong Luo department of chemical and biochemical engineering College of Chemistry and Chemical EngineeringXiamen University

A comprehensive 2D computational fluid dynamics （CFD） model was developed to simulate the flow behavior and catalytic dehydrogenation reaction of syngas in a heterogenous fixed-bed reactor （FBR）. The model combined the porous medium CFD model with a reaction kinetics model. To acquire an accu- rate reaction kinetics model, a comprehensive reaction mechanism was studied for the heterogeneous catalytic dehydrogenation reaction ofsyngas over a supported metal catalyst. Based on the reaction mech- anism and a statistical test, a reliable kinetics model was proposed. The CFD model combined with the above kinetics model was validated with one set of experimental data. The CFD model was also used to predict key reaction variable distributions such as the temperature and the component concentrations in the reactor.

关键词： Reaction engineering Multiphase reactor Packed bed Kinetics CFD Syngas dehydrogenation

Effect of manganese and potassium addition on CeO_2-Al_2O_3 catalyst for hydrogenation of benzoic acid to benzaldehyde

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2009年第5期27卷 723-727页

作者：程党国侯春阳陈丰秋詹晓力 department of chemical and biochemical engineering Zhejiang University

A series of Mn/CeO2-Al2O3 and K/CeO2-Al2O3 catalysts for hydrogenation of benzoic acid to benzaldehyde were prepared to in- vestigate the effect of Mn, K addition on CeO2-Al2O3 catalyst. X-ray diffraction (XRD) and H2-temperature-programmed reduction (H2-TPR) results suggested that the interaction between CeO2 and MnOx enhanced the reducibility of catalysts and therefore benzoic acid conversion. The addition of K increased the number of basic number on the catalyst which leads to a high selectivity to benzaldehyde, but excessive addition imposed negative effects on the catalyst performance. A Mn-K/CeO2-Al2O3 catalyst was developed and investigated in the reaction. The simultaneous addition of Mn and K enhanced not only the catalytic activity but also the capacity to resist the coke formation over catalyst.

关键词： benzaldehyde benzoic acid CeO2 manganese potassium rare earths

Harnessing photosynthetic microorganisms for enhanced bioremediation of microplastics:A comprehensive review

在线全文

学校读者我要写书评

暂无评论

Environmental Science and Ecotechnology 2024年第4期20卷 63-78页

作者： Giovanni Davide Barone Andres Rodríguez-Seijo Mattia Parati Brian Johnston Elif Erdem Tomislav Cernava Zhi Zhu Xufeng Liu Ilka MAxmann Peter Lindblad Iza Radecka Institute of Biology University of GrazUniversitatsplatz 28010GrazAustria Area de Edafoloxía Departamento de Bioloxía Vexetal e Ciencia Do SoloFacultade de CienciasUniversidade de Vigo32004OurenseSpain Agroecology and Food Institute(IAA) University of Vigo e Campus Auga32004OurenseSpain School of Life Sciences Faculty of Science and EngineeringUniversity of WolverhamptonWolverhamptonWV11LYUnited Kingdom FlexSea Ltd. LondonEC2A4NEUnited Kingdom department of chemical and biochemical engineering Technical University of Denmark2800Kongens LyngbyDenmark Institute of Environmental Biotechnology Graz University of Technology8010GrazAustria The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province School of Life SciencesJiangsu Normal University221116XuzhouChina department of ChemistrydÅngstrom Laboratory Uppsala UniversitySE-75120UppsalaSweden Synthetic Microbiology Department of BiologyHeinrich Heine University Düsseldorf40225DüsseldorfGermany Cluster of Excellence on Plant Sciences(CEPLAS) Heinrich HeineUniversity DüsseldorfD-40001DüsseldorfGermany

Mismanaged plastics,upon entering the environment,undergo degradation through physicochemical and/or biological *** process often results in the formation of microplastics(MPs),the most prevalent form of plastic debris(engineering strategies for enhanced *** review highlights the significance of alternative biomaterials and the exploration of strains expressing enzymes,such as polyethylene terephthalate(PET)hydrolases,in conjunction with microalgal and/or cyanobacterial ***,we delve into the promising potential of photo-biocatalytic approaches,emphasising the coupling of plastic debris degradation with sunlight *** integration of microalgal-bacterial consortia is explored for biotechnological applications against MPs and NPs pollution,showcasing the synergistic effects in wastewater treatment through the absorption of nitrogen,heavy metals,phosphorous,and *** conclusion,this review provides a comprehensive overview of the current state of research on the use of photoautotrophic cells for plastic *** underscores the need for continued investigation into the engineering of these microorganisms and the development of innovative approaches

关键词： Environmental biotechnology Microplastic Nanoplastic Microalgae Cyanobacteria

Stimulated Raman scattering tomography for rapid three-dimensional chemical imaging of cells and tissue

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical simulation of counter-current flow field in the downcomer of a liquid-solid circulating fluidized bed

Advanced Photonics 2024年第2期6卷 20-31页

作者： Weiqi Wang Zhiwei Huang National university of Singapore College of Design and EngineeringOptical Bioimaging LaboratoryDepartment of Biomedical EngineeringSingapore

Three-dimensional(3D)imaging is essential for understanding intricate biological and biomedical systems,yet live cell and tissue imaging applications still face challenges due to constrained imaging speed and strong scattering in turbid ***,we present a unique phase-modulated stimulated Raman scattering tomography(PM-SRST)technique to achieve rapid label-free 3D chemical imaging in cells and *** accomplish PM-SRST,we utilize a spatial light modulator to electronically manipulate the focused Stokes beam along the needle Bessel pump beam for SRS tomography without the need for mechanical z *** demonstrate the rapid 3D imaging capability of PM-SRST by real-time monitoring of 3D Brownian motion of polystyrene beads in water with 8.5 Hz volume rate,as well as the instant biochemical responses to acetic acid stimulants in MCF-7 ***,combining the Bessel pump beam with a longer wavelength Stokes beam(NIR-II window)provides a superior scattering resilient ability in PM-SRST,enabling rapid tomography in deeper tissue *** PM-SRST technique providestwofold enhancement in imaging depth in highly scattering media(e.g.,polymer beads phantom and biotissue like porcine skin and brain tissue)compared with conventional point-scan *** also demonstrate the rapid 3D imaging ability of PM-SRST by observing the dynamic diffusion and uptake processes of deuterium oxide molecules into plant *** rapid PM-SRST developed can be used to facilitate label-free 3D chemical imaging of metabolic activities and functional dynamic processes of drug delivery and therapeutics in live cells and tissue.

关键词： stimulated Raman scattering tomography deep tissue Raman imaging spatial light modulation

来源：评论

学校读者我要写书评

暂无评论

Particuology 2015年第4期13卷 48-54页

作者： Abbas Dadashi Chao Zhang Jingxu(Jesse)Zhu department of Mechanical and Materials engineering Western University department of chemical and biochemical engineering Western University

A comprehensive study on the hydrodynamics in the downcomer of a liquid-solid circulating fluidized bed （LSCFB） is crucial in the control and optimization of the extraction process using an ion exchange LSCFB. A computational fluid dynamics model is proposed in this study to simulate the counter-current two-phase flow in the downcomer of the LSCFB. The model is based on the Eulerian-Eulerian approach incorporating the kinetic theory of granular flow. The predicted results agree well with our earlier experimental data. Furthermore, it is shown that the bed expansion of the particles in the downcomer is directly affected by the superfcial liquid velocity in downcomer and solids circulation rate. The model also predicts the residence time of solid particles in the downcomer using a pulse technique. It is demonstrated that the increase in the superficial liquid velocity decreases the solids dispersion in the downcomer of the LSCFB,

关键词： Liquid-solid circulating fluidized bed Computational fluid dynamics Downcomer Two-phase flow Ion-exchange system

3D multiphase flow simulation of Marangoni convection on reactive absorption of CO_(2) by monoethanolamine in microchannel

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemical engineering 2022年第3期35卷 370-377页

作者： Shuai Chen Jiahong Lan Yu Zhang Jia Guo Zhikai Cao Yong Sha department of chemical and biochemical engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

A multiphase flow 3D numerical simulation method employing the coupled volume of fluid(VOF)and level set model is established to study the reactive absorption of CO_(2)by the monoethanolamine(MEA)aqueous solution in a falling film *** on the flow-reaction-mass transfer model of the MEA-CO_(2)system in the falling film microchannel,the enhancement effect of the Marangoni convection in this reactive absorption process is *** enhancement factor of the Marangoni convection obtained in this work is in good agreement with experimental results in the *** consideration of the absorption ratio as well as the enhancement effect of the Marangoni convection,the influence of different MEA concentrations on absorption of CO_(2)is ***,the appropriate MEA concentration for absorption enhanced by the Marangoni convection is acquired.

关键词： Numerical simulation Microchannel Falling film Marangoni convection MEA-CO_(2)

Investigation on catalytic distillation for ethyl acetate production with different catalytic packing structures

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemical engineering 2023年第1期53卷 63-72页

作者： Zhiwei Wang Yu Zhang Zhi Zhang Daowei Zhou Zhikai Cao Yong Sha department of chemical and biochemical engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

The catalytic packing is the core component of the catalytic distillation,and how the catalyst exists in the packing has significant influence on the *** investigate the effect of catalyst packings on the catalytic distillation process,the classical ethyl acetate reactive distillation system was utilized,and a supported catalytic packing(SCP)was prepared in comparison with the conventional tea-bag catalytic packing(TBP).Laboratory scale experiments showed that the ethyl acetate conversion of the SCP was superior to the TBP at a low catalyst *** effects of reaction kinetics,mass transfer performance and actual catalytic efficiency of the packings on this process were regarded as reasons and studied by combining the experiments and numerical *** suggested that the relatively immediate“in-situ separation”caused by the rapid reaction kinetics and better mass transfer performance of SCP may be a main reason for the difference of the conversion.

关键词： Catalytic packing Ethyl acetate Catalytic distillation Mass transfer Esterification Reaction kinetics

Supported catalytic packing prepared from ceramic packing for reactive distillation of ethyl acetate

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemical engineering 2022年第10期50卷 205-214页

作者： Zhiwei Wang Jiannan Shi Xiaonan Liu Zhikai Cao Yong Sha department of chemical and biochemical engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

In this work,a strategy of"etching-modification filling-graft copolymerization"was proposed to load the acidic ionic polyionic liquid on the smooth ceramic *** this way,commercial ceramic Raschig rings were successfully transformed into the supported catalytic packing for the reactive distillation,and were further evaluated with esterification reaction of ethyl acetate by means of the fully mixed reactor,the ultrasonic destruction,the cyclic catalysis reaction and the lab-scale distillation column *** catalyst coating has good adhesion with the *** can withstand 24 h of ultrasound damage and shows good stability in three cycle catalytic *** kind of coated catalyst has better catalytic activity than the commercial Amberlyst 15 *** the lab-scale reaction distillation,the supported catalyst Raschig ring can achieve a higher conversion in comparison with the tea bag catalytic packing of Amberlyst 15 dry under some conditions.

关键词： Supported catalyticpacking Ethyl acetate Reactive distillation Bonding strength

KINETICS OF SUSPENDED EMULSION POLYMERIZATION OF METHYL METHACRYLATE

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2004年第6期22卷 543-548页

作者：包永忠 department of chemical and biochemical engineering Zhejiang University Hangzhou 310027 China

The kinetics of suspended emulsion polymerization of methyl methacrylate (MMA), in which water acted as the dispersed phase and the mixture of NMA and cyclohexane as the continuous phase, was investigated. It showed that the initial polymerization rate (R-p0) and steady-state polymerization rate (R-p) were proportional to the mass ratio between water and oil phase, and increased as the polymerization temperature, the potassium persulphate concentration ([I]) and the Tween20 emulsifier concentration ([S]) increased. The relationships between the polymerization rate and [I] and [S] were obtained as follows: R-p0 proportional to [I](0.73)[S](0.32) and R-p proportional to [I](0.71)[S](0.23). The above exponents were close to those obtained from normal MMA emulsion polymerization. It also showed that the average molecular weight of the resulting poly(methyl methacrylate) decreased as the polymerization temperature, [I] and [S] increased. Thus, MMA suspended emulsion polymerization could be considered as a combination of many miniature emulsion polymerizations proceeding in water drops and obeyed the classical kinetics of MMA emulsion polymerization.

关键词： suspended emulsion polymerization methyl methacrylate polymerization rate average molecular weight and molecular weight distribution

Advancements in life-on-a-chip: The impact of “Beyond Limits Manufacturing” technology

在线全文

学校读者我要写书评

暂无评论

Chinese chemical Letters 2024年第5期35卷 13-16页

作者： Weiwei He Hongbo Zhang Xudong Lin Lili Zhu Tingting Zheng Hao Pei Yang Tian Min Zhang Guoyue Shi Lei Wu Jianlong Zhao Gulinuer Wumaier Shengqing Li Yufang Xu Honglin Li Xuhong Qian Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science and TechnologyShanghai 200237China School of Mechanical and Power engineering East China University of Science and TechnologyShanghai 200237China Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instrument School of Biomedical EngineeringShenzhen Campus of Sun Yat-sen UniversityShenzhen 518000China Shanghai Key Laboratory of Green Chemistry and chemical Processes Department of ChemistrySchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200241China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China department of Pulmonary and Critical Care Medicine Huashan HospitalFudan UniversityShanghai 200040China Innovation Center for AI and Drug Discovery East China Normal UniversityShanghai 200062China Lingang Laboratory Shanghai 200031China

This review explores the concept of life-on-a-chip,which involves the creation of miniaturized biological systems,such as organs,tissues,and model organisms,on microscale platforms called microfluidic *** chips consist of intricately etched channels,wells,and chambers that enable precise control and observation of fluids,cells,and biochemical reactions,facilitating the simulation of various aspects of human or animal physiology and the study of responses to different stimuli,drugs,or disease *** review highlights the application of a novel technology,“Beyond Limit Manufacturing”(BLM),in the development of sophisticated three-dimensional cell models and model organism ***-on-a-chip and organ-on-a-chip(OoC)are among the thriving developments in the field of microfluidics,allowing for the reconstruction of living microenvironments and implementation of multiple *** review discusses the latest advancements in life-on-a-chip technology using BLM and outlines potential future research directions,emphasizing the significant role of these chips in studying complex biological processes in a controlled and scalable manner.

关键词： Beyond Limit Manufacturing Model-organism-on-a-chip Organ-on-a-chip