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Particle Im.ge Velocim.try Study of Turbulence Characteristics in a Vessel Agitated by a Dual Rushton Im.eller

Chinese Journal of Chem.cal Engineering 2008年第5期16卷 700-708页

作者：刘心洪包雨云李志鹏高正明 john m. smith School of Chem.cal Engineering Beijing University of Chemical Technology Beijing 100029 China Fluids and System. Research Centre School of Engineering （J2） University of Surrey Guildford GU2 7XH UK

Particle Im.ge Velocim.try （PIV） has been used to investigate turbulence characteristics in a 0.48 m.diam.ter stirred vessel filled to a liquid height （ H = 1.4T ） of 0.67 m. The agitator had dual Rushton im.ellers of 0.19 m.diam.ter （ D = 0.4T ）. The developed flow patterns depend on the clearance of the lower im.eller above the base of the vessel, the spacing between the two im.ellers, and the subm.rgence of the upper im.eller below the liq- uid surface. Their com.inations can generate three basic flow patterns, nam.d, parallel, m.rging and diverging flows. The results of velocity m.asurem.nt show that the flow characteristics in the im.eller jet flow region changes very little for different positions. Average velocity, trailing vortices and shear strain rate distributions for three flow patterns were m.asured by using PIV technique. The characteristics of trailing vortex and its trajectory were described in detail for those three flow patterns. Since the space-resolution of PIV can only reach the sub-grid rather than the Kolm.gorov scale, a large-eddy PIV analysis has been used to estim.te the distribution of the turbulent kinetic energy dissipation. Com.arison of the distributions of turbulent kinetic energy and dissipation rate in m.rging flow shows that the highest turbulent kinetic energy and dissipation are both located in the vortex regions, but the m.xim. are at som.what different lo- cations behind the blade. About 37% of the total energy is dissipated in dual im.eller jet flow regions. The obtained distribution of shear strain rate for m.rging flow is sim.lar to that of turbulence dissipation, with the shear strain rate around the trailing vortices m.ch higher than in other areas.

关键词： dual Rushton im.eller flow pattern large-eddy particle im.ge velocim.try trailing vortex kinetic energy dissipation rate

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A stability evaluation m.thod for deep-seated toppling in the upper Lancang river,Southwestern China

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Journal of Rock m.chanics and Geotechnical Engineering 2024年第7期16卷 2388-2410页

作者： Yibing Ning Huim.ng Tang Jianbing Peng Yanjun Shen john V.smith Bocheng Zhang College of Geological Engineering and Geom.tics Chang’an UniversityXi’an710054China Academ. of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of Engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deform.tions exceeding 100 m.in *** slope deform.tion is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system.for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system.contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the m.chanical and kinem.tic analysis of slope blocks,the specific stage of slope m.vem.nt can be identified in the field through outcrop m.pping,in situ tests,surface displacem.nt m.nitoring,and adit and borehole *** stability evaluation m.thods are established based on the lim.ting equilibrium.theory and the strain com.atibility between the undisturbed zone and the toppled ***,several sam.le slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a m.xim.m.principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deform.tions along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deform.tion can be recognized by the layer sym.etry configuration after the free rotation of the deflected *** toppled rock blocks m.inly suffer sliding failures beyond the layer sym.etry *** factor of safety of the K73 rockslide decreased from.1.17 to 0.87 by considering the developm.nt of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling Evolutionary process Reservoir im.oundm.nt Rock slope

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Nonuniform.Dependence on the Initial Data for Solutions of Conservation Laws

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Com.unications on Applied m.them.tics and Com.utation 2024年第1期6卷 489-500页

作者： john m.Holm.s Barbara Lee Keyfitz Departm.nt of m.them.tics The Ohio State UniversityColumbusOH43210USA

In this paper,we study system. of conservation laws in one space *** prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution m.p is not uniform.y *** results apply to all nonlinear s... 详细信息

关键词： Conservation laws Data-to-solution m.p Nonuniform.dependence

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Therm.dynam.c analysis of m.tal segregation in dual phase high entropy ceram.cs

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Journal of m.teriom.cs 2024年第4期10卷 889-895页

作者： Steven m.smith II William.G.Fahrenholtz Gregory E.Hilm.s Stefano Curtarolo m.ssouri University of Science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke University Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke University Center of Autonomous Materials DesignDurhamNC27708USA

Equilibrium.Gibbs'free energy calculations were used to determ.ne m.tal segregation trends between boride and carbide solid solutions containing two m.tals that are relevant to dual phase high entropy *** m.del predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,Nb,m.,V,Hf,and Ta,which m.tches experim.ntal results of m.asured *** ratio of a m.tal in the carbide phase to the content of the sam. m.tal in the corresponding m.tal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a m.tal carbide reacting with B_(4)C to produce its corresponding m.tal boride and *** proposed m.del was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed m.del can be used to estim.te the segregation of m.tals in dual phase high entropy boride-carbide ceram.cs of any boride/carbide ratio or m.tal content.

关键词： Dual phase High entropy ceram.c Boride Carbide Therm.dynam.cs

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Im.unotherapy of gastric cancer:Present status and future perspectives

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World Journal of Gastroenterology 2024年第8期30卷 779-793页

作者： john K Triantafillidis m.nousos m.Konstadoulakis Apostolos E Papalois Inflam.atory Bowel Disease Unit “Metropolitan General”HospitalHolargos 15562AtticaGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece Second Departm.nt of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528AtticaGreece Unit of Surgical Research and Training Second Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528AtticaGreece

In this editorial,we com.ent on the article entitled“Advances and key focus areas in gastric cancer im.unotherapy:A com.rehensive scientom.tric and clinical trial review(1999-2023),”which was published in the recent issue of the World Journal of *** focused on the results of the authors’bibliom.tric analysis concerning gastric cancer im.unotherapy,which they analyzed in depth by com.iling the relevant publications of the last 20 *** that,we briefly describe the m.st recent data concerning the epidem.ological param.ters of gastric cancer(GC)in different countries,attem.ting to give an interpretation based on the etiological factors involved in the etiopathogenesis of the *** then briefly discuss the conservative treatm.nt(chem.therapy)of the various form. of this m.lignant *** describe the treatm.nt of resectable tum.rs,locally advanced neoplasm.,and unresectable(advanced)*** attention is given to m.dern therapeutic approaches with em.hasis on im.unotherapy,which seem. to be the future of GC treatm.nt,especially in com.ination with *** is also a thorough analysis of the results of the study under review in term. of the num.er of scientific publications,the countries in which the studies were conducted,the authors,and the scientific centers of origin,as well as the clinical studies in ***,an attem.t is m.de to draw som. conclusions and to point out possible future directions.

关键词： Gastric cancer Chem.therapy Im.unotherapy Im.une checkpoint inhibitors Bibliom.trics Scientom.trics

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Aerodynam.cs of a Tandem.Bladed Axial Com.ressor Rotor under Circum.erential Distortion at Different Rotational Speeds

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Journal of Therm.l Science 2024年第4期33卷 1340-1356页

作者： Am.t KUm.R Jerry T.john A.m.PRADEEP R.A.DAKKERm.NS Dragan KOZULOVIC Departm.nt of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India Departm.nt of Autom.tive and Aeronautical Engineering Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Propulsion Bundeswehr University Munich85577NeubibergGermany

For m.st aircraft engines,inflow distortion is *** distortion is known to degrade the aerodynam.c perform.nce and stable operating lim.ts of a *** rotor configuration is an arrangem.nt that effectively controls the growth of the boundary layer over the suction surface of the ***,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft *** is expected that the effect of inlet flow distortion would be m.re severe for a tandem.rotor design due to the greater flow turning inherent in such ***,this aspect needs to be thoroughly *** present study discusses the effect of circum.erential distortion on the tandem.rotor at different rotational ***-annulus RANS sim.lations using ANSYS CFX are used in the present *** perform.nce of the rotor at a particular flow coefficient and different rotational speeds is *** total pressure and efficiency are observed to drop at lower m.ss flow rates under the influence of circum.erential *** loss region in each blade passage is m.inly associated with the blade wake,tip leakage vortex,secondary flow,and boundary ***,their contribution varies from.passage to passage,particularly in the distorted *** the lower span,the wake width is found to be higher than that at a higher *** to the redistribution of the m.ss flow,the circum.erential extent reduces at a higher *** the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower *** distortion near the tip region prom.tes an early vortex breakdown even at the design operating *** adversely affects the total pressure,efficiency,and stall *** clean flow conditions,this phenom.non is only observed near the stall *** the design operating condition,the breakdown of the forward rotor tip l

关键词： tandem.rotor circum.erential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynam.cs of com.ressor blade

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A holistic approach to im.roving safety for battery energy storage system.

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Journal of Energy Chem.stry 2024年第5期92卷 422-439页

作者： Jam.s Close Jonathan E.Barnard Y.m.john Chew Sem.li Perera Departm.nt of Chem.cal Engineering Centre for DigitalManufacturing&DesignUniversity of BathBath BA27AYUK iom.saic International Lim.ted 16-18 Queen SquareBath BA12HNUK

The integration of battery energy storage system.(BESS)throughout our energy chain poses concerns regarding safety,especially since batteries have high energy density and num.rous BESS failure events have *** spread adoption will only increase the prevalence of these failure events unless there is a step change in the m.nagem.nt and design of *** understand the causes of failure,the m.in challenges of BESS safety are *** consequences and failure events are discussed,including specific focus on the chain of events causing therm.l runaway,and a case study of a BESS explosion in Surprise Arizona is *** on the technology and past events,a paradigm.shift is required to im.rove BESS *** this review,a holistic approach is *** com.ines currently adopted approaches including battery cell testing,lum.ed cell m.them.tical m.delling,and calorim.try,alongside additional m.asures taken to ensure BESS safety including the requirem.nt for com.utational fluid dynam.cs and kinetic m.delling,assessm.nt of installation level testing of the full BESS system.and not sim.ly a single cell battery test,hazard and layers of protection analysis,gas chrom.tography,and com.osition *** holistic approach proposed in this study aim. to address challenges of BESS safety and form.the basis of a paradigm.shift in the safety m.nagem.nt and design of these system..

关键词： Energy storagesystem. Process safety Battery safety Therm.l safety

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Enhancing Pneum.nia Detection in Pediatric Chest X-Rays Using CGAN-Augm.nted Datasets and Lightweight Deep Transfer Learning m.dels

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Journal of Data Analysis and Inform.tion Processing 2024年第1期12卷 1-23页

作者： Coulibaly m.ham.d Ronald Waweru m.angi john m. Kihoro Departm.nt of m.them.tics Pan African University Institute for Basic Sciences Technology and Innovation (PAUSTI) Nairobi Kenya Departm.nt of Com.uting Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya School of Com.uting and m.them.tics The Cooperative University of Kenya Nairobi Kenya

Pneum.nia ranks as a leading cause of m.rtality, particularly in children aged five and under. Detecting this disease typically requires radiologists to exam.ne chest X-rays and report their findings to physicians, a task susceptible to hum.n error. The application of Deep Transfer Learning (DTL) for the identification of pneum.nia through chest X-rays is hindered by a shortage of available im.ges, which has led to less than optim.l DTL perform.nce and issues with overfitting. Overfitting is characterized by a m.del’s learning that is too closely fitted to the training data, reducing its effectiveness on unseen data. The problem.of overfitting is especially prevalent in m.dical im.ge processing due to the high costs and extensive tim. required for im.ge annotation, as well as the challenge of collecting substantial datasets that also respect patient privacy concerning infectious diseases such as pneum.nia. To m.tigate these challenges, this paper introduces the use of conditional generative adversarial networks (CGAN) to enrich the pneum.nia dataset with 2690 synthesized X-ray im.ges of the m.nority class, aim.ng to even out the dataset distribution for im.roved diagnostic perform.nce. Subsequently, we applied four m.dified lightweight deep transfer learning m.dels such as Xception, m.bileNetV2, m.bileNet, and EfficientNetB0. These m.dels have been fine-tuned and evaluated, dem.nstrating rem.rkable detection accuracies of 99.26%, 98.23%, 97.06%, and 94.55%, respectively, across fifty epochs. The experim.ntal results validate that the m.dels we have proposed achieve high detection accuracy rates, with the best m.del reaching up to 99.26% effectiveness, outperform.ng other m.dels in the diagnosis of pneum.nia from.X-ray im.ges.

关键词： Pneum.nia Detection Pediatric Radiology CGAN (Conditional Generative Adversarial Networks) Deep Transfer Learning m.dical Im.ge Analysis

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Com.ination treatm.nt of inflam.atory bowel disease:Present status and future perspectives

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World Journal of Gastroenterology 2024年第15期30卷 2068-2080页

作者： john K Triantafillidis Constantinos G Zografos m.nousos m.Konstadoulakis Apostolos E Papalois Inflam.atory Bowel Disease Unit "Metropolitan General"HospitalHolargos 15562AtticaGreece Hellenic Society for Gastrointestinal Oncology 354 Iera OdosChaidari 12461AtticaGreece The 2^(nd)Departm.nt of Surgery University of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece Unit of Surgical Research and Training The 2^(nd)Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece

The treatm.nt of patients with inflam.atory bowel disease(IBD),especially those with severe or refractory disease,represents an im.ortant challenge for the clinical *** seem. to be no exaggeration to say that in these patients,not only the scientific background of the gastroenterologist is tested,but also the abundance of“gifts”that he should possess(insight,intuition,determ.ination,ability to take initiative,etc.)for the successful outcom. of the *** daily clinical practice,depending on the severity of the attack,IBD is treated with one or a com.ination of two or m.re pharm.ceutical *** com.in-ations include not only the first-line drugs(e.g.,m.salazine,corticosteroids,antibiotics,etc)but also second-and third-line drugs(im.unosuppressants and biologic agents).It is a fact that despite the significant therapeutic advances there is still a significant percentage of patients who do not satisfactorily respond to the treatm.nt ***,a part of these patients are going to *** recent years,several sm.ll-size clinical studies,reviews,and case reports have been published com.ining not only biological agents with other drugs(e.g.,im.unosuppressants or corticosteroids)but also the com.ination of two biologi-cal agents sim.ltaneously,especially in severe *** our opinion,it is at least a strange(and largely unexplained)fact that we often use com.inations of drugs in a given patient although studies com.aring the sim.ltaneous adm.nistration of two or m.re drugs with m.notherapy are very *** m.ntioned above,there is a tim.d tendency in the literature to com.ine two biological agents in severe cases unresponsive to the applied treatm.nt or patients with severe extraintestinal *** appropriate dosage,the duration of the adm.nistration,the suitable tim.ng for checking the clinical and laboratory outcom.,as well as the treatm.nt side-effects,should be the subject of intense clinical research *** this

关键词： Biologics for im.une-m.diated conditions Dual-targeted treatm.nt Com.ination treatm.nt Inflam.atory bowel disease Crohn’s

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Investigating low dispersion isotope dissolution Lu-Hf garnet dates via in situ Lu-Hf geochronology,Kanchenjunga Him.l

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Geoscience Frontiers 2024年第3期15卷 137-145页

作者： Kyle P.Larson john m.Cottle m.rk Button Brendan Dyck Iva Lihter Sudip Shrestha Departm.nt of Earth Environmental and Geographic SciencesUniversity of British ColumbiaOkanaganKelownaCanada Departm.nt of Earth Science University of CaliforniaSanta BarbaraUSA Fipke Laboratory for Trace Elem.nt Research University of British ColumbiaOkanaganKelownaCanada

Re-exam.nation of three specim.ns from.the Kanchenjunga Him.l of Nepal via in situ Lu-Hf garnet geochronology yields evidence of m.ltiple garnet growth *** analyses from.grain cores in two specim.ns define Paleozoic regressions whereas analyses from.grain rim. in the sam. specim.ns define low-precision regressions consistent with the tim.ng of Him.layan *** dates contrast with previously published low dispersion,ca.290 m. isotope dissolution(ID)Lu-Hf garnet dates for the sam. *** of Lu and spot age distribution in representative grains from.the specim.ns exam.ned yields calculated dates that approxim.te the Perm.an-age regressions through the original ID *** findings dem.nstrate that it is possible to generate low dispersion ID Lu-Hf data from.m.ltigenerational garnet with significantly different-age growth events when approxim.tely equal proportions of the different age reservoirs are included in m.lti-com.onent aliquots.

关键词： Lu-Hf geochronology In situ Lu-Hf geochronology Kanchenjunga Him.l

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