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Hydrodynamics and heat transfer of gas-solid two-phase mixtures flowing through packed beds——a review

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Progress in Natural Science:Materials International 2008年第10期18卷 1185-1196页

作者： Ngoc Thang Cong Institute of Particle Science & Engineering University of LeedsClarendon RoadLeeds LS2 9JTUK

Flow of a gas-solid two-phase mixture through a packed bed is relevant to a number of industrial processes such as heat recovery and filtration of dusty flue gases,iron making in shaft reactors,gas purification,and sorption enhanced reaction processes.In spite of the industrial relevance,little work has been reported in the literature.The limited amount of research work has mainly addressed the mac- roscopic hydrodynamics in terms of pressure drop and solids hold-ups at the ambient temperature.Very little is done,until fairly recent, on solids motion at the single particle level,hydrodynamics at elevated temperatures and heat transfer.This paper reviews the recent development in the field including both the hydrodynamics and heat transfer of gas-solid two-phase mixtures flowing through packed beds,which is believed to represent the state-of-the-art in the field.The review is not aimed to be exhaustive but rather focused on our own work carried out over the past few years in the Institute of Particle Science & Engineering at the University of Leeds.And some of our results are compared with that of other groups.

关键词： Gas-solid two-phase flow Hydrodynamics Heat transfer pept Euler-Euler multi-fluid model

副溶血弧菌毒力相关因子pept和FleQ的生物学功能研究

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副溶血弧菌毒力相关因子PepT和FleQ的生物学功能研究

作者：齐瑜中国农业科学院

学位级别：硕士

副溶血弧菌（Vibrio parahaemolyticus,VP）是一种革兰氏阴性嗜盐微生物,可引起鱼和对虾早期死亡综合征及急性肝胰腺坏死病,严重威胁国内外水产养殖业的健康发展。副溶血弧菌也是一种重要的食源性肠道致病菌,食用受污染或未煮熟的海鲜,... 详细信息

副溶血弧菌（Vibrio parahaemolyticus,VP）是一种革兰氏阴性嗜盐微生物,可引起鱼和对虾早期死亡综合征及急性肝胰腺坏死病,严重威胁国内外水产养殖业的健康发展。副溶血弧菌也是一种重要的食源性肠道致病菌,食用受污染或未煮熟的海鲜,能引发急性胃肠炎,还可通过伤口感染导致败血症。副溶血弧菌之所以能造成严重危害,主要依赖于其多种毒力因子。金属依赖性肽酶T（peptidase T,pept）,能高特异性催化三肽N端氨基酸,因此也称为氨肽酶T。氨肽酶参与蛋白质的翻译后修饰、分解和成熟等生理过程,在一系列生物过程和疾病情况中发挥着至关重要的作用。fleQ基因编码一种属于Ntr C家族的AAA+ATP酶细菌增强子结合蛋白,通过与σ因子共同作用激活特定基因的转录起始。Ntr C是一种氮代谢调控蛋白,在细菌中普遍存在,是响应氮调节基因表达的全局调控蛋白,Ntr C及其同源替代sigma因子Rpo N通过调节gmh D的基因表达在生物被膜形成过程中发挥重要作用。本研究以pept和FleQ为研究对象,开展其对副溶血弧菌生物学功能和致病性机制的研究,为发掘潜在药物靶标治疗和预防VP感染提供新思路。结果如下:1、副溶血弧菌pept和fleQ基因缺失株及回补株的构建选取M20家族氨肽酶pept和Ntr C家族增强子结合蛋白FleQ,通过同源重组技术分别构建两个基因的缺失株及回补株,经PCR验证各基因缺失株及回补株均可稳定遗传。通过q RT-PCR对各菌株中目的基因转录水平分析,Δpept和ΔfleQ无目的基因转录,而野生株和回补株中目的基因转录水平正常。经过生长曲线测定,表明缺失pept和fleQ基因后不影响副溶血弧菌的生长。2、pept基因缺失对副溶血弧菌生物学功能及致病性的影响本试验通过比较pept基因缺失株与野生株在运动性、环境耐受、生物被膜、细胞毒性和细菌鞭毛相关基因的转录水平的差异,结果表明,与野生株相比,Δpept浮游运动能力减弱（Ppept生物被膜形成能力减弱至野生株的0.4倍;而细菌群集运动及环境耐受能力无显著差异（P>0.05）。此外,缺失pept基因导致对副溶血弧菌的细胞毒性下降至60%,小鼠存活率为40%。以上主要研究pept基因缺失对副溶血弧菌的生物学功能及小鼠致病性的影响。3、fleQ基因缺失对副溶血弧菌生物学功能及致病性的影响本试验通过运动性、生物被膜形成能力、细胞毒性和小鼠毒力试验发现,fleQ基因缺失后,副溶血弧菌浮游运动（Ppept和FleQ与该菌环境适应性和致病性密切相关,是其重要的毒力相关因子,为该菌的防控打下理论基础。

关键词：副溶血弧菌 pept FleQ 致病性

Pain Exposure Physical Therapy(pept)in Complex Regional Pain Syndrome Type 1:A Systematic Review

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Journal of Pharmacy and Pharmacology 2019年第3期7卷 124-131页

作者： Nicoli Greco Müller Glória Maria Moraes Vianna da Rosa Graduated by Centro Universitário IBMR FVS’s Gymnasium Sports PhysiotherapyEFI PhysiotherapyRio de JaneiroRJBrazil School of Physiotherapy Serra dos Orgaos University Center(UNIFESO)TeresolisRJBrazil

Complex regional pain syndrome type 1(CRPS-1)is a debilitating and progressive pathology in which chronic symptoms affect the functional capacity,and there are discussions about its best form of intervention.The aim of this study was to investigate the effectiveness of pain exposure physical therapy(pept)on functional recovery of these patients and to compare with conventional treatment.Systematized bibliographic searches were performed with qualitative and quantitative exploratory objective of scientific articles of the last 10 years in the databases PubMed,EBSCO and PEDro.Three studies were selected to analyze:Ek et al.(2009)conducted evaluations at baseline and 3 months after the last session,with 106 patients.The evaluations by Meent et al.‘s paper(2011)realized pre-treatment and 12 months after last session,with 20 patients.In Barnhoorn et al.‘s article(2015)the only one to perform controlled and randomized study with 56 patients divided into pept and conventional,and evaluations were pre-treatment,3,6,and 9 months after the last session;performed 5 treatment sessions of 40 minutes,as well as in the other studies.There were positive and significant outcomes on the intervention of pept in CRPS-1,showing that this treatment is effective in functional recovery of these patients.

关键词： Reflex sympathetic dystrophy pept quality of life

正电子发射型颗粒追踪技术在矿物加工中的应用

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煤炭工程 2018年第11期50卷 131-135页

作者：叶贵川马力强黄根中国矿业大学(北京)化学与环境工程学院北京100083

作为检测颗粒运动行为的先进手段,正电子发射型颗粒追踪技术(pept)近几年已在矿物加工领域有了一定的应用。本文主要就pept工作原理进行了简介,总结了该技术近几年在螺旋选矿、浮选、旋流器以及磨矿等工艺中的应用,就pept技术在矿物加... 详细信息

作为检测颗粒运动行为的先进手段,正电子发射型颗粒追踪技术(pept)近几年已在矿物加工领域有了一定的应用。本文主要就pept工作原理进行了简介,总结了该技术近几年在螺旋选矿、浮选、旋流器以及磨矿等工艺中的应用,就pept技术在矿物加工中的应用前景进行了分析。结果表明:作为一种先进的颗粒追踪技术,利用pept可以直观监测到颗粒在螺旋选矿机、水力旋流器以及浮选过程中的运动规律,也能对磨机运行状态以及研磨介质运动状态进行监测,这对明确设备运行机制具有重要意义。未来pept技术也应在TBS分选机、摇床、调浆机等设备中用于测定和表征颗粒运动状态,利用pept计算研究物料特性和结构参数对颗粒运动的影响,将有利于完善矿物加工理论,为设备的优化提供指导。

关键词：颗粒追踪 pept 矿物加工螺旋选矿机磨矿

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多重转运体介导的褪黑素的转运及其对抗肿瘤作用的影响

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多重转运体介导的褪黑素的转运及其对抗肿瘤作用的影响

作者：冯胜男大连医科大学

学位级别：硕士

第一部分多重转运体介导的褪黑素及其代谢产物的转运目的:褪黑素是松果体分泌的一种神经激素,具有多种多样的生物学作用,包括调节免疫应答、抗氧化、神经保护作用和抗肿瘤活性等,外源性褪黑素被广泛应用于临床上多种疾病的治疗,代谢产... 详细信息

第一部分多重转运体介导的褪黑素及其代谢产物的转运目的:褪黑素是松果体分泌的一种神经激素,具有多种多样的生物学作用,包括调节免疫应答、抗氧化、神经保护作用和抗肿瘤活性等,外源性褪黑素被广泛应用于临床上多种疾病的治疗,代谢产物中磺酸化产物约占90%以上,但褪黑素及其代谢产物的体内各器官中的转运机制尚不明确,本部分实验旨在阐明转运体介导的褪黑素及其代谢产物在肠、肾等器官的处置过程。方法:本研究建立了灵敏、快速的LC-MS/MS方法检测生物样品中褪黑素（Mel）及其代谢产物（6-OM、NAS、6OM-S和NAS-S）的浓度,应用Caco-2、pept1/2-HeLa、OAT1/3-HEK293和OCT2-HEK293细胞摄取实验考察褪黑素及其代谢产物在肠道、肾脏的转运是否与pept1/2、OAT1/3和OCT2有关。结果:Caco-2细胞对褪黑素在2min内呈线性摄取,且可以被乌苯美司（Bes,1 mM）显著的抑制,Caco-2细胞对褪黑素的摄取为双向动力学模型,高/低亲和力的Km分别为22.2 μM 和588μM,最适pH值为5.5。pept1-HeLa 和pept2-HeLa对褪黑素的摄取都显著性高于mock-HeLa细胞,且能被Bes显著抑制。pept1/2-HeLa细胞对褪黑素摄取2min内呈为线性,同样符合双向动力学模型,Km值分别为0.6 mM和1.0 mM。pept1-HeLa细胞和pept2-HeLa细胞对褪黑素摄取的最佳pH值分别为6.0和7.0。6-OM和NAS经pept1/2-HeLa的摄取与mock-HeLa细胞无显著性统计学差异,甘氨酸-肌氨酸（Gly-Sar）也不能抑制pept1/2-HeLa对6-OM和NAS的摄取,二者都不是pept的底物。甘氨酸-肌氨酸（Gly-Sar）、乌苯美司（Bes）、青霉素G（PCG）、赖诺普利（Lis）和缬沙坦（Val）能够抑制Caco-2细胞对褪黑素的摄取,对褪黑素经pept1/2-HeLa摄取的抑制作用更明显,尤其是Lis和Val抑制率达90%以上。OAT1/3-HEK293和OCT2-HEK293细胞对Mel,6-OM以及NAS的摄取无明显差异,同时OAT抑制剂丙磺舒（Probenecid）、OCT抑制剂维拉帕米（Verapamil）对Mel、6-OM 和 NAS的摄取无明显抑制。6OM-S和NAS-S也不是OCT2的底物。OAT3-HEK293细胞对6OM-S和NAS-S的摄取值分别是mock-HEK293细胞的3.34和8.88倍,丙磺舒能够抑制OAT3-HEK293细胞对6OM-S和NAS-S摄取值的90%,OAT3对6OM-S和NAS-S的Km分别为138.4μM、304.2μM。结论:（1）褪黑素是pept1和pept2的底物;（2）褪黑素在人体的代谢产物6OM-S和NAS-S是OAT3的底物;（3）当褪黑素与pept、OAT3等转运体底物药物联合应用时,存在转运体介导的DDI风险。第二部分pept1/2介导的摄取对褪黑素抗肿瘤作用的影响目的:本部分实验拟研究褪黑素抗肿瘤作用与pept转运体的关系,揭示pept1/2介导的靶向转运对褪黑素抗肿瘤的影响。方法:筛选8种肿瘤细胞对褪黑素的摄取及pept表达量,选择pept1和pept2高表达的模型细胞,通过改变对肿瘤细胞的培养条件,从而影响pept1/2的表达水平,观察肿瘤细胞对褪黑素摄取量的变化,再通过MTT实验和western blot技术分析这种变化对褪黑素抗肿瘤作用的影响。结果:PC3、DU145、U118、SHSY-5Y、MCF-7、HepG2、H1975、A549细胞中,PC3和U118细胞对褪黑素的摄取在5min和24h都最为显著,western blot实验显示PC3细胞中的pept1表达量最高,且未检测到pept2的蛋白信号,U118细胞中的pept2有较高水平的表达,且pept1信号极弱。最终PC3和U118被选定为pept1/2高表达的模型细胞。PC3和U118细胞经15%FBS诱导后,pept1和pept2的表达上调,褪黑素对PC3和U118细胞活力的抑制作用也显著增强。褪黑素通过下调p-ERK及p-Akt水平,抑制ERK和Akt磷酸化,从而抑制肿瘤细胞增殖,通过抑制CyclinD1和CDK4的表达从而抑制细胞周期的运转,阻滞细胞周期于GO/S期。15%FBS诱导48h后褪黑素对p-ERK、p-Akt、CyclinD1和CDK4的抑制作用更明显,抑制肿瘤细胞增殖的作用更强。结论:（1）PC3和U118细胞可作为pept1、pept2高表达的模型细胞;（2）肿瘤微环境中的高营养状态能诱导pept1/2表达;（3）高营养条件下褪黑素的抗肿瘤作用增强;（4）pept1/2介导的摄取使褪黑素在肿瘤靶向集聚,增强抗肿瘤作用。

关键词：褪黑素 pept OAT 抗肿瘤高营养

pept1,Mdr1a和Mrp2在不同年龄大鼠十二指肠中的表达（英文）

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遵义医学院学报 2015年第1期38卷 20-24页

作者：陈舒徐尚福刘杰陆远富遵义医学院基础药理省部共建教育部重点实验室贵州遵义563099

目的观察不同年龄SD大鼠十二指肠药物转运体pept1,Mdr1a和Mrp2的mRNA水平的变化。方法收集胚胎期(-2 d),哺乳期(1、7、14 d),儿童期(21、28、35 d),青年期(60、180 d),老龄化期(540、800 d)SD大鼠十二指肠,分离总RNA,采用Real-Time PCR... 详细信息

目的观察不同年龄SD大鼠十二指肠药物转运体pept1,Mdr1a和Mrp2的mRNA水平的变化。方法收集胚胎期(-2 d),哺乳期(1、7、14 d),儿童期(21、28、35 d),青年期(60、180 d),老龄化期(540、800 d)SD大鼠十二指肠,分离总RNA,采用Real-Time PCR法检测肠摄入转运体pept1和肠外排转运体Mrd1a和Mrp2的mRNA水平。结果 pept1 mRNA的表达水平在新生鼠表达最高,随后随着年龄的增长而下降,断奶后趋于平稳。Mdr1a和Mrp2 mRNA表达水平在出生后7d达到峰值,随年龄的增长而下降,60 d后维持一定水平不变。结论 pept1、Mdr1a、Mrp2 mRNA水平随年龄变化而不同,由此推测不同年龄大鼠对上述转运体介导的药物吸收存在差异。

关键词： pept Mdr Mrp 发育年龄转运体

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Experimental verification of the scaling relationships for bubbling gas-fluidised beds using the pept technique

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Experimental verification of the scaling relationships for b...

Segregation of granular flow in the transverse plane of a rolling mode rotating drum

CCAST“颗粒物理”研讨会

作者： M.Stein Y.L.Ding J.P.K.Seville School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK School of Chemical Engineering University of Birmingham Edgbaston. Birmingham B15 2TT UK

＜正＞ An experimental verification of the scaling relationships for bubbling gas-fluidised beds has been carried out by measuring particle cycle frequency. The Positron Emission Particle Tracking technique was used, which enabled non-intrusive measurements of solids motion in three dimensions with a spatial resolution of -2 mm under the conditions of this work. Three cylindrical beds （70, 141 and 240 mm ID） equipped with multiple orifice-type distributors were tested. It was shown that for geometrically similar beds, the pair of Froude numbers based on the minimum fluidisation and excess gas velocities was sufficient for similarity at the viscous limit. The experimental results showed little influence of the gas-to-particle density ratio, but a small effect of particle-to-bed diameter ratio when the change in the ratio was significant. The experimental results also indicated a possible relaxation of the viscous limit up to a particle Reynolds number of about 100. More experimental studies are needed to confirm the validity of such a relaxation. 2002 Elsevier Science Ltd. All rights reserved.

关键词： Bubbling gas-fluidised beds Scaling relationships Solids motion Experimental validation Viscous limit pept

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Segregation of granular flow in the transverse plane of a ro...

Solids motion in rolling mode rotating drums operated at low to medium rotational speeds

CCAST“颗粒物理”研讨会

作者： Y.L.Ding R.Forster J.P.K.Seville D.J.Parker School of Chemical Engineering. University of Birmingham Edgbaston. Birmingham B15 2TT UK Positron Imaging Centre. University of Birmingham. Edgbaston Birmingham B15 2TT. UK School of Physics and Astronomy University of Birmingham. Edghaston. Birmingham B15 2TT UK Positron Imaging Centre. University of Birmingham Edgbuston. Birmingham B15 2TT. UK School of Chemical Engineering. University of Birmingham. Edgbaston. Birmingham B15 2TT UK Positron Imaging Centre University oj Birmingham Edgbaston Birmingham B15 2TT. UK School of Physics and Astronomy University of Birmingham. Eagbaston. Birmingham B15 2TT UK Positron Imaging Centre. University of Birmingham. Edgbaston. Birmingham B15 2TT. UK

＜正＞ This paper reports some observations on the behaviour of a segregated particle bed consisting of a mixture of small and large particles in the transverse plane of a rolling mode rotating drum. A non-invasive positron emission particle tracking （PERT） technique was used to follow the trajectories of different sized particles. A two-dimensional mathematical model based on the Eulerian approach and the thin layer approximation was developed to simulate solids motion and concentration distribution of different sized particles. It is shown that the bed structure for a binary mixture is similar to that for mono-sized particles, i.e. two-region structure consisting of a relatively thin ’active’ region and a ’passive’ region near the drum wall where particles move as a rigid body. At low rotational speeds, the velocity difference between small and large particles of a binary system is negligible in both the active and passive regions. At relatively high rotational speeds, the velocity difference is small in the active region and negligible in the passive region. Radial occupancy data suggest that small particles tend to concentrate in the core region, whereas large particles tend to occupy the shell region, in good agreement with model predictions. Axial occupancy data reveal that the axial particle mobility increases with drum rotational speed, and the mutual diffusivity of small particles is higher than that of large particles. It is also shown that the turnover time ratio of small to large particles is almost independent of concentrations of small particles under the conditions of this work. 2002 Elsevier Science Ltd. All rights reserved.

关键词： Particle segregation Solids motion Rotating drum Rolling mode Bed turnover time Mathematical modelling pept

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Solids motion in rolling mode rotating drums operated at low...