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Vir.ual exper.mentation thr.ugh 3D full-loop simulation of a cir.ulating fluidized bed

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Par.icuology 2008年第6期6卷 529-539页

作者： Nan Zhang bona.lu Wei Wang Jinghai li State Key labor.tor. of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Gr.duate Univer.ity of the Chinese Academy of Sciences Beijing 100049 China

Euler.an gr.nular.multiphase model with a dr.g coefficient cor.ection based on the ener.y-minimization multi-scale （EMMS） model was used to simulate a semi-industr. scale cir.ulating fluidized bed （CFB）. Thr.e-dimensional （3D）, time-dependent simulation of a full-loop CFB r.vealed that the axial pr.files of cr.ss-sectionally aver.ged solid volume fr.ction, and the r.dial pr.files of solid axial velocity and solid volume fr.ction wer. in r.asonable agr.ement with exper.mental data. Based on this agr.ement, database der.ved fr.m exper.ments not yet accomplished was r.plenished with such simulations, and fluid r.gime diagr.ms and pr.ssur. balance ar.und the CFB loop wer. der.ved accor.ingly. This wor. pr.sents an integr.ted viewpoint on CFB and unfolds a fr.sh par.digm for.CFB modeling, which can be expected to help r.solve cer.ain issues long in dispute but bar. for.exper.ments.

关键词： CFD Cir.ulating fluidized bed Multiphase flow Simulation Choking Cluster

Extending EMMS-based models to CFB boiler.applications

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Par.icuology 2012年第6期10卷 663-671页

作者： bona.lu Nan Zhang Wei Wang Jinghai li State Key labor.tor. of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

r.cently, EMMS-based models ar. being widely applied in simulations of high-thr.ughput cir.ulating fluidized beds （CFBs） with fine par.icles. Its use for.low flux systems, such as CFB boiler.（CFBB）, still r.mains unexplor.d. In this wor., it has been found that the or.ginal definition of cluster.diameter.in EMMS model is unsuitable for.simulations of the CFB boiler.with low solids flux. To r.medy this, we pr.pose a new model of cluster.diameter. The EMMS-based dr.g model （EMMS/matr.x model） with this r.vised cluster.definition is validated thr.ugh the computational fluid dynamics （CFD） simulation of a CFB boiler.

关键词： EMMS Cluster.Cir.ulating fluidized bed Boiler.CFD Simulation

Steady-state multiscale CFD simulation of a cir.ulating fluidized bed r.ser

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Par.icuology 2024年第10期93卷 54-64页

作者： Zhaojie Ke Yujie Tian Fei li bona.lu Wei Wang State Key labor.tor. of Mesoscience and Engineer.ng Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineer.ng University of Chinese Academy of SciencesBeijing100049China

Compar.d to tr.nsient simulation,steady-state simulation of cir.ulating fluidized bed r.ser. is mor. efficient,but is also har.er.to per.or. due to the complex scale-dependency of dense gas-solid *** this wor.,steady-state computational fluid dynamics(CFD)simulation of a r.ser.is per.or.ed using the steady ener.y-minimization multi-scale(EMMS)*** is found that the steady state cor.esponds to an extr.mely lar.e scale of length and time,thus the gr.d size r.quir.d in steady-state simulation is lar.er.than that in tr.nsient *** time-aver.ged two-fluid model(TFM)coupled with the steady-state EMMS/1M dr.g model enables a good pr.diction of the S-shaped,axial solids distr.bution and the choking tr.nsition,wher.as the two-phase tur.ulence and solids str.ss models ar. impor.ant in pr.dicting the r.dially cor.-annular.distr.bution of *** far.as we know,this is the fir.t time that one can pr.dict the choking tr.nsition in a steady-state CFD *** impr.vement may need an EMMS modeling of the time-aver.ged solid str.sses.

关键词： Fluidization Dr.g for.e Steady state Simulation Mesoscale

Numer.cal compar.son of two modes of gas-solid r.ser.oper.tion： Fluid catalytic cr.cking vs CFB combustor

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Par.icuology 2017年第2期15卷 42-48页

作者： Yifeng Mei Mingzhao Zhao bona.lu Sheng Chen Wei Wang Star. Key labor.tor. afMultiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China School of Chemical Engineer.ng Sichuan University Chengdu 610065 China Star. Key labor.tor. of Heavy Oil Pr.cessing China University of Petroleum Beijing 102249 China Univer.ity of Chinese Academy of Sciences Beijing 100049 China

Two modes of gas-solid r.ser.oper.tion, i.e., fluid catalytic cr.cking （FCC） and cir.ulating fluidized bed combustor.（CFBC）, have been r.cognized in liter.tur.; par.icular.y in the under.tanding of choking phenomena. This wor. compar.s these two modes of oper.tion thr.ugh computational fluid dynamics （CFD） simulation. In CFD simulations, the differ.nt oper.tions ar. r.pr.sented by fixing appr.pr.ate boundar. conditions： solids flux or.solids inventor.. It is found that the FCC and CFBC modes gener.lly have the same dependence of solids flux on the mean solids volume fr.ction or.solids inventor.. However. dur.ng the choking tr.nsition, the FCC mode of oper.tion needs mor. time to r.ach a steady state; thus the FCC system may have insufficient time to r.spond to valve adjustments or.flow state change, leading to the choking. The differ.nce between FCC and CFBC systems is mor. pr.nounced for.the systems with longer.r.ser.. A mor. detailed investigation of these two modes of r.ser.oper.tion may r.quir. a thr.e-dimensional full loop simulation with dynamic valve adjustment.

关键词： Fluidization Computational fluid dynamics Simulation Fluid catalytic cr.cking Cir.ulating fluidized bed Choking

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毛织物的防缩整理

国外纺织技术（化纤．染整．环境保护分册） 1995年第1期 22-26页

作者： bona.,IM 胡石羽

Will digital solution tr.nsfor. Sub-Sahar. Afr.can agr.cultur.?

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Ar.ificial Intelligence in Agr.cultur. 2021年第1期5卷 292-300页

作者： Gezahagn Kudama Mabir.tu Dangia Hika Wana bona.Tadese Wollega Univer.ity Shambu CampusDepartment of Agricultural EconomicsShambuEthiopia Gambella Univer.ity Department of Agricultural EconomicsGambellaEthiopia

Given its super.or.impor.ance of digital agr.cultur.l solutions to over.ome challenges in agr.cultur.l activities,many of the solutions ar. in face of challenges to scale in Sub-Sahar.n Afr.ca(SSA).On the other.hand,the impact of digitalization on economic development in developing countr.es is documented in sever.l liter.tur.s but digital technologies have lately touched the agr.cultur.l sector.in *** objective of this study was to br.efly r.viewthe impact of digital solution on smallholder.far.er. agr.cultur. tr.nsfor.ation,and the key and challenges influencing of agr.cultur.l digitalization in *** used all-inclusive appr.ach compr.sing or.ginal r.sear.h ar.icles,peer.r.viewed ar.icles,wor.ing paper.,confer.nce paper.,book chapter.,database,guide book,and indexes fr.m 60 r.cent empir.cal academic studies conducted on impacts on digital solution in the r.gion to pr.duce a br.ad *** showthat digital solution,when effectively used in SSA,has enabled smallholder.far.er. to gain a wide r.nge of benefits involving access to r.al timely pr.ce,mar.et,and far.ing infor.ation and safe financial tr.nsactions,alter.ative value chain linkages,multifaceted knowledge,better.ear.ing and yield,r.duce costs,social well-being and r.sk minimization,women empower.ent *** contr.st,fail to use adaptable tools,unaffor.ability,digital illiter.teness,low par.icipation of women and old smallholder.far.er. due to their.low income and education status,ar. main bar.ier. to digitalization in ***,it essential to the SSA countr.es to invest on technologies that is adaptable their.tar.et population,ensur. balancing r.gulator. and deliver. appr.aches that per.it equal involvement ofwomen,old age categor.,and r.mote ar.as,r.alize affor.able access to digital ser.ices thr.ugh r.ducing data costs and tax cuts on digital agr.cultur.l tools,and offer.ng digital skill tr.ining for.far.er. by segmenting them into their.gender.age,and education to fully har.es

关键词： Agr.cultur. Digital solution and ser.ice Digitalization Tr.nsfor.ation

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53例肝移植术后感染的预防和治疗经验

德国医学 1993年第2期10卷 118-120页

作者： bona.,H 袁才章

Extending the EMMS/bubbling model to fluidization of binar. par.icle mixtur.: For.ulation and steady-state validation

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Chinese Jour.al of Chemical Engineer.ng 2019年第1期27卷 54-62页

作者： Nouman Ahmad Yujie Tian bona.lu Kun Hong Haifeng Wang Wei Wang State Key labor.tor. of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences Univer.ity of Chinese Academy of Sciences Jiangsu Pr.vincial Engineer.ng labor.tor. for.Advanced Mater.als of Salt Chemical Industr. Huaiyin Institute of Technology

The EMMS/bubbling model or.ginally pr.posed for.fluidization of monodisper.e par.icles is extended to fluidization of binar. par.icle mixtur. in this *** dense and dilute phases ar. consider.d to compr.se of two types of par.icles differ.ng in size and/or.*** equations and the stability condition ar. then for.ulated and solved by using an optimization numer.cal *** effects of bubble diameter.ar. fir.t investigated and a suitable bubble diameter.cor.elation is *** validation for.steady state behavior.shows the extended model can fair.y captur. the over.ll hydr.dynamic behavior. in ter.s of volume fr.ction of bubbles and aver.ge bed voidage for.both monodisper.e and binar. par.icle *** encour.ges us to integr.te this model with CFD for.mor. validations in the futur..

关键词： EMMS Binar. mixtur. Fluidization Mesoscale str.ctur.

Update on deep br.in stimulation in Par.inson’s disease

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Tr.nslational Neur.degener.tion 2015年第1期4卷 84-91页

作者： Daniel Mar.inez-r.mir.z Wei Hu Alber.o r.bona.Michael S.Okun Apar.a Wagle Shukla Depar.ment of Neur.logy University of FloridaCollege of MedicineCenter for Movement Disorders and Neurorestoration3450 Hull RoadGainesvilleFL 32607USA Depar.ment of Neur.sur.er. Psychiatryand HistoryUniversity of FloridaCollege of MedicineCenter for Movement Disorders and NeurorestorationGainesvilleFL 32610USA

Deep br.in stimulation(DBS)is consider.d a safe and well toler.ted sur.ical pr.cedur. to alleviate Par.inson’s disease(PD)and other.movement disor.er. symptoms along with some psychiatr.c *** the last few decades DBS has been shown to pr.vide r.mar.able ther.peutic effect on car.fully selected *** its pr.cise mechanism of action is still unknown,DBS impr.ves motor.functions and ther.for. quality of *** date,two main tar.ets have emer.ed in PD patients:the globus pallidus par. inter.a and the subthalamic *** other.tar.ets,the ventr.lis inter.edius and zona incer.a have also been selectively used,especially in tr.mor.dominant PD *** main indications for.PD DBS have tr.ditionally been motor.fluctuations,debilitating medication induced dyskinesias,unpr.dictable“off time”state,and medication r.fr.ctor. *** r.fr.ctor. tr.mor.and intoler.ble dyskinesia ar. potential palliative *** afor.mentioned tar.ets,the br.instem pedunculopontine nucleus(PPN)is under.investigation for.the tr.atment of ON-state fr.ezing of gait and postur.l *** this ar.icle,we will r.view the most r.cent liter.tur. on DBS ther.py for.PD,including cutting-edge advances and data suppor.ing the r.le of DBS in advanced neur.l-networ. modulation.

关键词： Movement disor.er. Subthalamic nucleus Globus pallidus Neur.l networ. Br.in modulation Closed-loop