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Particle mixing rates using the two-fluid model

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Particuology 2018年第1期16卷 13-26页

作者： M. Banaei n.g. deen M. van Sint Annaland J.A.M. Kuipers Multiphase Reactors group Deportment of Chemical Engineering & Chemistry Eindhoven University of Technology 5600 MB Eindhoven The Netherlands Dutch Polymer Institute (DPI) 5600 AX Eindhoven The Netherlands Multiphase and Reactive Flows group Department of Mechanical Engineering Eindhoven University of Technology 5600 MB Eindhoven The Netherlands

In this work, a new methodology is introduced to calculate the solids mixing rate in dense gas-fluidized beds using the two-fluid model. The implementation of this methodology into an existing two-fluid model code was carefully verified. The solids phase continuity equation was satisfied using our method, and the sensitivity of the computational results to the time step, computational cell size, and discretization scheme was investigated to determine the optimal simulation settings. Using these simulation settings, the degree of solids mixing was observed to rapidly （exponentially） increase with increasing operating pressure and linearly decrease with increasing bed diameter. Our novel methodology can be applied to analyze mixing processes in large lab-scale beds as an alternative to existing time-consuming simulation techniques such as computational fluid dynamics combined with the discrete element model.

关键词： gas-solid fluidized bed Simulation Two-fluid model Solids mixing Pressure Scale up

Borescopic particle image velocimetry in bubbling gas-solid fluidized beds

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Particuology 2019年第2期17卷 66-75页

作者： M. Banaei R. Dellaert n.g. deen J.A.M. Kuipers M. van Sint Annaland Multiphase Reactors group Department of Chemical Engineering & Chemistry Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands Dutch Polymer Institute (DPI) P.O. Box 902 5600 AX Eindhoven The Netherlands Multiphase and Reactive Flows group. Department of Mechanical Engineering Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands

In this work, the borescopic particle image velocimetry (BPIV) technique was applied to a bubbling gas-solid fluidized bed, and the results were compared with published positron emission particle tracking (PEPT) measurement data. Before performing the experiments, the sensitivity of the BPIV results to the illumination power, light reflectivity of the particles, and location of the borescope was also investigated. The BPIV and PEPT results were in fair agreement;however, some discrepancies were observed.The difference between the two sets of results were mainly caused by the intrusiveness of BPIV, the fact that the local solids volume fraction was not accounted for in the BPIV analysis, and the intrinsic differences of these two methods. Therefore, measurement of the local solids volume fraction with the borescope is highly recommended for further development of the BPIV method, which will also enable measureme nt of the local solids mass fluxes in side dense gas-solid fluidized beds.

关键词： Borescopic particle image velocimetry gas-solid bubbling fluidized bed Solid velocity profile Experimental investigation Hydrodynamics

Coefficient of restitution for particles impacting on wet surfaces： An improved experimental approach

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Particuology 2016年第2期14卷 1-9页

作者： B. Cunger V. Salikov S. Heinrich S. Antonyuk V.S. Sutkar n.g. deen J.A.M. Kuipers Institute of Solids Process Engineering and Particle Technology Hamburg University of Technology Denickestrasse 15 21073 Hamburg Germany Particle Process Engineering Department of Mechanical and Process Engineering University ofKaiserslautern Cottlieb-Daimler-Strasse 67663 Kaiserslautern Germany Multiphase Reactors group Department of Chemical Engineering and Chemistry Eindhoven University of Technology P.O. Box 513 5600 MB EindhovenThe Netherlands

The coefficient of restitution is widely used to characterize the energy dissipation rate in numerical simulations involving particle collisions. The challenge in measuring the coefficient of restitution is the strong scatter seen in experimental data that results from varying particle properties, i.e. shape and surface roughness, and from imperfections in the experimental technique. To minimize this scattering, a novel experimental setup was developed based on two synchronized high-speed cameras capturing the collision behaviour of a particle in three dimensions. To measure the wet restitution coefficient, which describes particle impact in the presence of a liquid layer in the contact region, additional accuracy can be achieved by measuring the liquid layer thickness by a high-precision optical confocal sensor. The coefficient of restitution was measured for glass particles with two different diameters, at different relative velocities and liquid layer thicknesses, with a focus on small collision velocities and thin liquid layers, using both the improved （three dimensional） and the conventional （two dimensional） approaches to quantify the improvement of the new method＇s accuracy.

关键词： Particle impact Coefficient of restitution Liquid layer Improved experimental setup

甲状腺功能正常的缺血性心肌病患者血清甲状腺激素浓度与血清nT-proBnP、同型半胱氨酸浓度的相关性

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岭南心血管病杂志 2024年第1期30卷 72-80页

作者：刘俊荣金德恩界首市人民医院心血管内科一病区安徽界首236500

目的探讨甲状腺功能正常的缺血性心肌病(ischemic cardiomyopathy,ICM)患者血清甲状腺激素浓度与血清n末端B型脑钠肽前体(n-terminal pro-B-type natriuretic peptide,nT-proBnP)、同型半胱氨酸(homocysteine,Hcy)浓度的相关性。方法选择界首市人民医院2021年8月至2022年8月收治的124例甲状腺功能正常的ICM患者作为研究对象。对所有患者根据美国纽约心脏协会(new York Heart Association,nYHA)心功能分级分为Ⅰ级组29例,Ⅱ级组27例,Ⅲ级组43例,Ⅳ级组25例;同时根据颈动脉内膜中层厚度(carotid intimamedia thickness,CIMT)分为CIMT增厚组41例,CIMT正常组83例。检测所有受试者的血清甲状腺激素[游离三碘甲状腺原氨酸(free triiodothyronine,FT3)、游离甲状腺素(free thyroxine,FT4)、促甲状腺激素(thyroid stimulating hormone,TSH)]浓度以及血清nT-proBnP、Hcy浓度;测定入选对象超声心动图指标,包括左心室射血分数(left ventricular ejection fraction,LVEF)、左心室舒张末期内径(left ventricular end diastolic diameter,LVEDD)、左心房内径(left atrial diameter,LAD),对入选对象行冠状动脉计算机断层扫描(computed tomography,CT)血管造影检查,并计算gensini积分。分析血清甲状腺激素浓度与血清nT-proBnP、Hcy浓度等实验室指标的相关性。结果采用Bonferroni法行多重比较发现,Ⅰ、Ⅱ、Ⅲ、Ⅳ级组患者和CIMT组患者之间血清TSH、nT-proBnP、Hcy浓度比较,差异均有统计学意义(Pgensini积分均显著高于Ⅰ级组,差异有统计学意义(PnT-proBnP、Hcy浓度和LVEDD、gensini积分均显著高于CIMT正常组,差异有统计学意义(PnT-proBnP、Hcy浓度和nYHA心功能分级、CIMT、gensini积分均呈负相关(PnT-proBnP、Hcy浓度和nYHA心功能分级、CIMT、LVEDD、LAD、gensini积分均呈正相关(PnT-proBnP、Hcy浓度以及心功能分级、CIMT增厚与否、心脏结构与功能状态、冠状动脉病变程度密切相关;血清FT3、FT4浓度与血清nT-proBnP、Hcy浓度以及nYHA心功能分级、CIMT、gensini积分均呈负相关,与LVEF均呈正相关;血清TSH浓度与血清nT-proBnP、Hcy浓度以及nYHA心功能分级、CIMT、LVEDD、LAD、gensini积分均呈正相关,与LVEF呈负相关。

关键词：缺血性心肌病甲状腺功能甲状腺激素 n末端B型脑钠肽前体同型半胱氨酸颈动脉内膜中层厚度

An oxide-based heterojunction optoelectronic synaptic device with wideband and rapid response performance

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Journal of Materials Science & Technology 2022年第28期123卷 159-167页

作者： Chunmei Li Jinyong Wang Dongyang Li nasir Ilyas Zhiqiang Yang Kexin Chen Peng gu Xiangdong Jiang Deen.g. Fucai Liu Yadong Jiang Wei Li School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Information Materials of Sichuan Province and School of Preparatory Education Southwest Minzu UniversityChengdu 610041China

With the rapid development of science and technology,the emergence of new application scenarios,such as robots,driverless vehicles and smart city,puts forward high requirements for artificial visual systems.Optoelectronic synaptic devices have attracted much attention due to their advantages in sensing,memory and computing integration.In this work,via band structure engineering and heterostructure designing,a heterojunction optoelectronic synaptic device based on Cu doped with n-type SrTiO_(3)(Cu:STO)film combined with p-type CuAlO_(2)(CAO)thin film was fabricated.It is found surprisingly that the optoelectronic device based on Cu:STO/CAO p-n heterojunction exhibits a rapid response of 2 ms,and that it has a wideband response from visible to near-infrared(nIR)region.Additionally,a series of important synaptic functions,including excitatory postsynaptic current(EPSC),paired-pulse facilitation(PPF),shortterm potentiation(STP)to long-term potentiation(LTP)transition,learning experience behavior and image sharpening,have been successfully simulated on the device.More importantly,the performance of the device remains still stable and reliable after several months which were stored at room temperature and atmospheric pressure.Based on these advantages,the optoelectronic synaptic devices demonstrated here provide great potential in the new generation of artificial visual systems.

关键词： Cu:STO/CAO heterojunction Optoelectronic synaptic devices Vis to nIR wideband Rapid response Artificial visual system

The effect of cryotherapy application before versus after subcutaneous anticoagulant injection on pain intensity and hematoma formation: A quasi-experimental design

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International Journal of nursing Sciences 2018年第3期5卷 223-229页

作者： Dalia Salah El-deen n.g.aa F.A.Youssef Medical-Surgical nursing Department Faculty of NursingCairo UniversityEgypt Medical-Surgical nursing Department College of NursingPrincess Nourah bint Abdulrahman UniversityKingdom of Saudi Arabia

Objective:To investigate the effect of cryotherapy application before versus after subcutaneous anticoagulant injection(SCAI)on pain intensity and hematoma formation.Methods:A quasi-experimental design was utilized.A convenient sample of 105 adult patients,who were admitted to one of the biggest teaching hospitals in Cairo and receiving SCAI,were recruited over a period of six months.Patients were randomly allocated into three groups:A Control group who received the routine hospital care(g1,n=35)and two intervention.g.oup who received cryotherapy for 5-min.g.:cryotherapy applied before SCAI,n=35;g3:cryotherapy applied after SCAI,n=35).Demographic and medical history data sheet,Pain numeric Rating Scale and Hematoma Formation and Size Assessment Scale were used to collect the data.Results:The pain intensity among the patients in the two intervention.g.oups(g2:Median=1.0;g3:Median=0)was significantly lower than in the control group(g1,Median=3.0).no significant difference was found between.g. and g3(P=0.728).Applying cryotherapy after SCAI(g3)decreased the frequency of hematoma formation(48hrs=31.4%&72hrs=28.5%)compared to applying it before injection.g.,100%)or not applying it(g1,100%).The size of hematoma in.g. was smaller than that in.g.(Pnclusion:Applying cryotherapy significantly decreased pain intensity and hematoma occurrence/size.Applying cryotherapy after injection was more effective in preventing hematoma formation and decreasing its size than applying it before injection.

关键词： Anticoagulants Cryotherapy Hematoma Injections Subcutaneous Pain

Enhanced protective coatings on Ti-10V-2Fe-3Al alloy through anodizing and post-sealing with layered double hydroxides

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Journal of Materials Science & Technology 2020年第2期37卷 104-113页

作者： Lei Liua Liang Wu Xiaobo Chen deen Sun Yuan Chen.g.n Zhang Xingxing Ding Fusheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing 400044China national Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Engineering RMIT UniversityCity CampusCarltonVIC3053Australia

Anodic oxidation is a prevalent technique to introduce superior corrosion and wear resistance upon the surface of titanium(Ti)alloys,in which the selection of appropriate electrolytes and defect-sealing strategies is a key.This study aims to address such issues through anodizing Ti-10V-2Fe-3Al alloy in malic acid,followed by a post-sealing treatment with Mg-Al layered double hydroxides(LDHs).The characteristics of the samples were investigated using scanning electron microscopy(SEM),atomic force microscopy(AFM),glow discharge optical emission spectroscopy(gDOES),X-ray diffraction(XRD)and energy-dispersive X-ray spectroscopy(EDS).SEM micrographs reveals that the anodic coating had a surface full of bulges and cracks,and was almost sealed by the following LDHs treatment.XRD pattern indicate that the anodic coating was mainly consisted of amorphous TiO2 with a small fraction of anatase,but its crystallization degree was increased through the post-sealing.Moreover,electrochemical and tribological measurements demonstrate that corrosion current density was 2.8×10-6,2.0×10-7,5.9×10-9A cm-2,and wear rate was 1.45×10-3,1.30×10-4 and 6.90×10-5 mm3 n-1 m-1 for respective bare Ti-10V-2Fe-3Al alloy substrate,anodized specimens without and with the LDHs post treatment.Finally,a plausible wear mechanism was proposed.

关键词： Titanium alloy Malic acid Layered double hydroxides Sealing Corrosion resistance Tribological properties

Epidemioclinical Aspects of Childhood Domestic Accidents in the Emergency Department of Boffa Hospital

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Open Journal of Pediatrics 2023年第6期13卷 947-954页

作者： Bangoura Mmah Aminata Kolié Ouo Ouo Bangoura Kaba Camara Salématou Hassimiou Diop Mamadou Moustapha Touré Oumar deen Camara Emmanuel Diallo Fatoumata Binta Bémy Pé néabey Touré Mariame Oumar Institut de nutrition et de Santé de l’Enfant Conakry Guinée Service de pédiatrie Hô pital national Donka Conakry Guinée Service de chirurgie pédiatrique Hô pital national Donka Conakry Guinée Hô pital préfectoral de Boffa Boffa Guinée

Introduction: Domestic accidents are defined as accidents that occur in the home or its immediate surroundings. Objective: To describe the epidemioclinical and therapeutic aspects. Patients and Methods: Prospective, descriptive study from July 1, 2019 to June 30, 2020 in the emergency department of Boffa prefectural hospital included all children aged 0 to 15 years admitted for domestic accidents. Results: Of 120 cases of accidental trauma, 56 were domestic accidents. The mean age was 7.08 years. The 0 - 5 and 11 - 15 age groups were the most represented (35.71%). The sex ratio was 1.55 in favor of boys. Domestic accidents were represented by falls (26.78%), thermal burns (21.43%), snakebite wounds (17.86%) and dog bites (10.71%), drowning (5.36%), and electrification by lightning (3.60%), one case or 1.78% of each of the following: esophageal foreign body by palm nut, firearm, wall collapse, stretching of upper limb. Paracetamol was the molecule most frequently used (89.28%). The outcome was favorable in 92.86% of cases. However, four (4) deaths were recorded. Conclusion: Domestic accidents remain a significant pathology at Boffa prefectural hospital.

关键词： Domestic Accidents Children Hospital Prefecture Boffa guinea Conakry

Risk Factors for neonatal Mortality at the Institute of nutrition and Child Health of the Donka/guinea-Conakry national Hospital

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Open Journal of Pediatrics 2024年第2期14卷 327-337页

作者： Bangoura Mmah Aminata Kolié Ouo Ouo Camara Salématou Hassimiou Baldé Mariama Bangoura Kaba Diop Mamadou Moustapha Camara Emmanuel Diallo Fatoumata Binta Doukouré Mamadou Aliou Mamadou Mouctar Sow Bémy Pé néabey Institut de nutrition et de Santé de l’Enfant Conakry Guinea Service de Pédiatrie Hô pital National Donka Conakry Guinea Service de Pédiatrie Hô pital National d’Ignace Deen Conakry Guinea

Introduction: The birth of a baby is a moment of joy and celebration. However, the neonatal period is a very delicate phase of life. neonatal mortality rates remain high in low-income countries. In.g.inea, after 20 years, this rate has fallen from 34.2% in 1998 to 32% in 2018. Objective: To identify the main risk factors for neonatal mortality. Methods: This was an observational, analytical case-control study, lasting 6 months from January 1 to June 30, 2019, conducted at the Institut de nutrition et de la Santé de l’Enfant (InSE) at Donka national Hospital. Results: We collected 242 cases and 242 controls, i.e. a total of 484 records. 748 patients were registered, with 32.35% deaths. 82.86% of deaths occurred in the early neonatal period. Statistical analysis revealed the main risk factors: prematurity (RQ 7.39 95% CI 3.27 - 16.61 p = 0.0000003), hypothermia (RQ 2.29 95% CI 1.51 - 3.46 p = 0.0001), acute fetal distress (RQ 2.13 95% CI 1.33 - 3.43 p = 0.0016), low birth weight (QR 1.91 95% CI 1.12 - 3.24 p = 0.016), home birth (QR 3.26 95% CI 1.25 - 8.46 p = 0.015). Conclusion: neonatal mortality is a health problem in the InSE neonatology department. To reduce the mortality rate in this referral facility, it is essential to equip it and provide ongoing training for staff.

关键词： neonatal Mortality InSE guinea-Conakry