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Co.rse to.Fine: The Ro.e o. Severe Plastic Defo.matio. in Advancing Titanium-Based Medical Implants - A Co.prehensive Review

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Jo.rnal o. Wuhan University o. Techno.o.y(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlo.ić Bo.an I Međo.Ivana Lj Cvijo.ić-Alagić Veljko.R Djo.ić Faculty o. Techno.o.y and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča Institute o. Nuclear Sci-ences-Natio.al Institute o. the Republic o. Serbia University of Belgrade11001BeogradSerbia Inno.atio. Centre o. the Faculty o. Techno.o.y and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic defo.matio.(SPD)pro.edures,which are utilized to.fo.m an ultrafine-grained structure in metallic *** the SPD pro.ess,a so.id material sample is subjected to.very high lo.ds witho.t a significant change in sample *** the present wo.k,the high-pressure to.sio.(HPT)pro.ess,as o.e o. the SPD techniques,which achieves a high degree o. defo.matio. and ensures refinement o. the micro.tructure,will be discussed in mo.e *** that grain size co.tro. is accepted as a metho. to.o.tain materials with desired characteristics,an o.erview o. the pro.erties o. ultrafine-grained titanium-based bio.aterials to.be used in medicine is ***,particular attentio. is dedicated to.the influences o. HPT pro.ess parameters,primarily hydro.tatic pressure,and number o. revo.utio.s during to.sio.,o. the grain size and physical and mechanical characteristics(mo.ulus o. elasticity,micro.ardness,and tensile pro.erties),co.ro.io. resistance,and bio.o.patibility o. the titanium-based bio.aterials.A review o. the literature indicates that titanium-based materials o.tained by the SPD pro.ess sho. impro.ed mechanical and physical pro.erties witho.t lo.ing bio.o.patibility and co.ro.io. resistance,which suggests that these metho.s o. o.taining implants are so.ething that sho.ld be further develo.ed in the future.

关键词： high-pressure to.sio. pro.ess ultrafine-grained titanium-based materials electro.hemical ano.izatio. physical pro.erties mechanical pro.erties

Dynamic stress co.centratio. in an infinitely lo.g cylindrical cavity due to.a po.nt spherical so.rce embedded within a fluid-saturated po.o.lastic fo.matio. o. infinite extent

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Applied Mathematics and Mechanics(English Editio.) 2025年第1期46卷 139-156页

作者： H.Ho.SEINI o.BALILASHAKI Department o. Mechanical Engineering Faculty of EngineeringGolestan University

The effects o. a harmo.ically exciting mo.o.o.e so.rce o. an infinitely lo.g cylindrical cavity embedded entirely within a fluid-saturated po.o.lastic fo.matio. o. infinite extent are examined theo.etically. It is assumed that the so.rce is lo.ated o.tside the cavity at a specified distance fro. the bo.eho.e axis. The magnitudes o. the ho.p and radial stresses beside the po.e pressures exerted o. the interface and inside the po.o.s medium surro.nding the bo.eho.e are calculated and discussed. Bio.'s po.o.lastic mo.eling alo.g with three types o. bo.ndary co.ditio.s fo. the cylindrical interface including the ideal fluid, empty bo.eho.e, and rigid inclusio. with a hard bo.ndary is emplo.ed fo. the analysis. Utilizing a pro.er translatio.al additio. theo.em fo. expressing the incident spherical wave in terms o. cylindrical wave expansio.s, the pro.o.ed bo.ndary co.ditio.s at the interface are satisfied. Stresses are fo.mulated by means o. wave po.ential functio.s in a three-dimensio.al(3D) manner. The effects o. the frequency and the radial distance between the so.rce and bo.eho.e o. the induced stresses are examined fo. the first cylindrical mo.es o.er frequency spectra. Two.permeability co.ditio.s fo. the interface and three types o. so.ls fo. the po.o.s fo.matio. are co.sidered thro.gho.t the analysis. To.give an o.erall o.tline o. the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has co.siderable effects o. the induced stress values. In additio., the interface permeability co.ditio. and so.l characteristics play an impo.tant ro.e in determining the dynamic respo.se o. the bo.eho.e. Finally,the o.tained results are co.pared with the relevant analyses existing in the literature fo. so.e limit cases, and go.d agreement is achieved.

关键词： po.nt so.rce cylindrical cavity po.o.s medium wave-field transfo.matio. stress co.centratio. o.53.4

气体团簇离子束装置的设计及其在表面平坦化、自组装纳米结构中的应用

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物理学报 2020年第9期69卷 113-122页

作者：曾晓梅 vasiliy pelenovich Rakhim Rakhimo. 左文彬邢斌罗进宝张翔宇付德君武汉大学物理科学与技术学院武汉430072 武汉大学动力与机械学院武汉430072

根据超声膨胀原理,n(10-10^4)个气体原子可以绝热冷却后凝聚在一起形成团簇,经过离化后,形成带一个电荷量的团簇离子,比如Arn^+.当团簇离子与固体材料相互作用时,由于平均每个原子携带的能量(~eV)较低,仅作用于材料浅表面区域,因此,气... 详细信息

根据超声膨胀原理,n(10-10^4)个气体原子可以绝热冷却后凝聚在一起形成团簇,经过离化后,形成带一个电荷量的团簇离子,比如Arn^+.当团簇离子与固体材料相互作用时,由于平均每个原子携带的能量(~eV)较低,仅作用于材料浅表面区域,因此,气体团簇离子束是材料表面改性的优良选择.本文介绍了一台由武汉大学加速器实验室自主研制的气体团簇离子束装置,包括整体构造、工作原理及实验应用.中性团簇束由金属锥形喷嘴(F=65-135μm,q=14°)形成,平均尺寸为3000 ato.s/cluster,经离化后,其离子束流达到了50μ***团簇离子因其反应活性较低,本文运用Ar团簇离子(平均尺寸为1000 ato.s/cluster)进行了平坦化和自组装纳米结构的研究.单晶硅片经Ar团簇离子束处理后,均方根粗糙度由初始的1.92 nm降低到0.5 nm,同时观察到了束流的清洁效应.利用Ar团簇离子束的倾斜(30°-60°)轰击,在宽大平坦的单晶Zno.片上形成了纳米波纹,而在Zno.米棒表面则形成了有序的纳米台阶,同时,利用二维功率谱密度函数分析了纳米结构在基片上的表面形貌和特征分布,并计算了纳米波纹的尺寸和数量.

关键词：气体团簇离子束表面平坦化自组装纳米结构功率谱密度函数

离子剂量比在气体团簇多级能量平坦化模式中的作用

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物理学报 2021年第22期70卷 48-54页

作者：罗进宝 vasiliy pelenovich 曾晓梅郝中华张翔宇左文彬付德君武汉大学物理科学与技术学院武汉430072 武汉大学动力与机械学院武汉430072

本研究提出采用两种不同的离子剂量比的气体团簇离子束多级能量模式来改善n-Si(100)单晶片的创伤表面.模式一采用低剂量的高能量团簇和高剂量的低能量团簇组合,模式二则采用高剂量的高能量团簇和低剂量的低能量团簇组合.结果证明,模式... 详细信息

本研究提出采用两种不同的离子剂量比的气体团簇离子束多级能量模式来改善n-Si(100)单晶片的创伤表面.模式一采用低剂量的高能量团簇和高剂量的低能量团簇组合,模式二则采用高剂量的高能量团簇和低剂量的低能量团簇组合.结果证明,模式一的平坦化效果优于模式二,两者的均方根粗糙度分别为0.62 nm和1.02 nm.本文在研究多级能量模式平坦化前,先做了单一能量团簇轰击带有机械损伤的Si片实验,来验证创伤去除、离子损伤程度与团簇能量的关系.结果证明,当用15 kV高压加速团簇离子时,划痕去除效率最高,最终表面划痕很浅,但粗糙度下降不明显;当用8 kV,5 kV低压加速团簇离子时,样品表面变得细腻,遗留的离子损伤最轻.然后将多级能量模式一与单一能量团簇轰击靶材进行对比,结果表明,与单一15 keV的高能团簇处理相比,多级能量模式可以获得更为平坦的靶材表面;与单一5 keV的低能团簇处理相比,多级能量模式可以更好的去除划痕等创伤.多级能量模式一将高、低能团簇优点集中起来,从而达到最佳的平坦化效果.

关键词：气体团簇离子束表面平坦化离子剂量比多级能量模式表面粗糙度

Predictio. o. selected bio.iesel fuel pro.erties using artificial neural netwo.k

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Fro.tiers in Energy 2015年第4期9卷 433-445页

作者： So.o.o. o. GIWA Sunday o. ADEKo.AYA Kayo.e o. ADAMA Mo.uf o. MUKAILA Department o. Agricultural and Mechanical Engineering College of Engineering and Environmental Studies Olabisi Onabanjo University lbogun Campus Ifo Ogun State Nigeria

Bio.iesel is an alternative fuel to.replace fo.sil- based diesel fuel. It has fuel pro.erties similar to.diesel which are generally determined experimentally. The experimental determinatio. o. vario.s pro.erties o. bio.iesel is co.tly, time co.suming and a tedio.s pro.ess. To.so.ve these pro.lems, artificial neural netwo.k （ANN） has been co.sidered as a vital to.l fo. estimating the fuel pro.erties o. bio.iesel, especially fro. its fatty acid （FA） co.po.itio.. In this study, fo.r ANNs have been designed and trained to.predict the cetane number （CN）, flash po.nt （FP）, kinematic visco.ity （KV） and density o. bio.iesel using ANN with lo.sig and purelin transfer functio.s in the hidden layer o. all the netwo.ks. The five mo.t prevalent FAs fro. 55 feedsto.ks fo.nd in the literature utilized as the input parameters fo. the mo.el are palmitic, stearic, o.eic, lino.eic and lino.enie acids except fo. density netwo.k with a sixth parameter （temperature）. o.her FAs that are present in the bio.iesels have been co.sidered based o. the number o. carbo. ato. chains and the level o. saturatio.. Fro. this study, the predictio. accuracy and the average abso.ute deviatio. o. the netwo.ks are CN （96.69%; 1.637%）, KV （95.80%; 1.638%）, FP （99.07%; 0.997%） and density （99.40%; 0.101%）. These values are reaso.ably better co.pared to.previo.s studies o. empirical co.relatio.s and ANN predictio.s o. these fuel pro.erties fo.nd in literature. Hence, the present study demo.strates the ability o. ANN mo.el to.predict fuel pro.erties o. bio.iesel with high accuracy.

关键词： bio.iesel fuel pro.erties artificial neuralnetwo.k fatty acid predictio.

Co.po.ite Co.tro. o. No.linear Singularly Perturbed Systems via Appro.imate Feedback Linearizatio.

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Internatio.al Jo.rnal o. Auto.atio. and co.puting 2020年第4期17卷 610-620页

作者： Aleksey Kabano. vasiliy Alchako. Sevasto.o. State University Sevastopol 299053Russian Federation

This article is devo.ed to.the pro.lem o. co.po.ite co.tro. design fo. co.tinuo.s no.linear singularly perturbed(SP)system using appro.imate feedback linearizatio.(AFL)*** essence o. AFL metho. lies in the feedback linearizatio. o.ly o. a certain part o. the o.iginal no.linear *** to.AFL appro.ch,we suggest to.so.ve feedback linearizatio. pro.lems fo. co.tinuo.s no.linear SP system by reducing it to.two.feedback linearizatio. pro.lems fo. slo. and fast subsystems *** resulting AFL co.tro. is co.structed in the fo.m o. asympto.ic co.po.itio.(co.po.ite co.tro.).Standard pro.edure fo. the co.po.ite co.tro. design co.sists o. the fo.lo.ing steps:1)system deco.po.itio.,2)so.utio. o. co.tro. pro.lem fo. fast subsystem,3)so.utio. o. co.tro. pro.lem fo. slo. subsystem,4)co.structio. o. the resulting co.tro. in the fo.m o. the co.po.itio. o. slo. and fast *** main difficulty during system deco.po.itio. is asso.iated with dynamics separatio. co.ditio. fo. no.linear SP *** o.erco.e this,we pro.o.e to.change the sequence o. the design pro.edure:1)so.ving the co.tro. pro.lem fo. fast state variables part,2)system deco.po.itio.,3)so.ving the co.tro. pro.lem fo. slo. state variables part,4)co.structio. o. the resulting co.po.ite *** this way,fast feedback linearizing co.tro. is cho.en so.that the dynamics separatio. co.ditio. wo.ld be met and the fast subsystem wo.ld be *** applicatio. o. the pro.o.ed appro.ch is illustrated thro.gh several examples.

关键词： Appro.imate feedback linearizatio.(AFL) co.po.ite co.tro. no.linear singularly perturbed system o.der reductio. deco.po.itio.

Breakage o. dro.s and bubbles in a stirred tank： A review o.experimental studies

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Chinese Jo.rnal o. Chemical Engineering 2017年第6期25卷 698-711页

作者： Basim o. Hasan Department o. Chemical Engineering Technical University of Berlin 6ermany Department o. Chemical Engineering AI-Nahrain University lraq

The rate o. breakage o. dro.s and bubbles(fluid particles) in stirred systems is o. great co.sequence o. mass,heat, and mo.entum transpo.t pheno.ena. Therefo.e, o.er the years, the to.ic has gained a co.siderable attentio. fro. the researchers to.study and characterize this pheno.eno.. In present wo.k, the experimental studies o. breakage pheno.eno. in a stirred tank in the last fo.r decades were reviewed. The review highlighted the investigated experimental co.ditio.s and the majo. findings co.cerning the breakage mechanism and the effect o. o.erating co.ditio.s. The discrepancy and co.tradictio.s o. the o.tco.es o. tho.e studies were specified and discussed. Experimental o.servatio.s and co.clusio.s co.cerning the breakage characterizatio. parameters,such as defo.matio., breakage pro.ability, breakage time, and breakage lo.atio. were presented and co.mented o.. Po.sible future refinements and pro.pective were reco.mended. The review indicated that there are clear discrepancies and co.tradictio.s between previo.s studies regarding the effect o. so.e o.erating parameters and the values o. breakage time, breakage pro.ability, number o. daughter particles, and breakage lo.atio. relative to.the impeller. In additio., there are still many scientific gaps that need to.be studied and characterized in future by o.erco.ing specific experimental difficulties and uncertainties.

关键词： Dro. Bubble Breakage Stirred tank Review Breakage rate

Hyperfine Structure o. Several So.ls fro. Western Hubei and Inner Mo.go.ia Studied by Mo.sbauer Spectro.co.y

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Wuhan University Jo.rnal o. Natural Sciences 2014年第3期19卷 257-261页

作者： pelenovich V o.CHEN Yilo.g XIAo.Renzheng LIU Sho.yin FU Dejun Department o. Physics and Techno.o.y Huazhong Normal University Key Labo.ato.y o. Artificial Micro.and Nano.Materials o. Ministry o. Educatio. and Accelerato. Labo.ato.y School of Physics and TechnologyWuhan University

So.l samples taken fro. Xilamuren Grassland,Reso.ant Sand Bay,Inner Mo.go.ia,and Yichang,western Hubei Pro.ince were investigated by Mssbauer spectro.co.y at ro.m temperature and 20 *** was supplemented with phase identificatio. and elemental analysis to.o.tain info.matio. abo.t the co.po.itio. and structure types o. Fe-co.taining *** samples co.lected fro. bo.h Xilamuren Grassland and Reso.ant Sand Bay,Inner Mo.go.ia were fo.nd to.have small amo.nt o. iro. 1%-2%.The main phases were determined as silica,albite,and *** o. three do.inant do.blets were o.served in the Mssbauer spectra o. these samples,respectively and identified as co.respo.ding to.the valence states o. Fe2＋and Fe3＋.A sextet o.served in all the spectra is attributed to.the hematite *** temperature Mssbauer measurements have revealed Mo.in transitio..

关键词： Mo.sbauer spectro.co.y hyperfine structure hematite

Physio.o.ical and mo.ecular bio.hemical mechanisms o. bile fo.matio.

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Wo.ld Jo.rnal o. Gastro.ntero.o.y 2013年第42期19卷 7341-7360页

作者： vasiliy Ivano.ich Reshetnyak V.A. Nego.sky Scientific Research Institute o. General Reanimato.o.y Russian Academy of Medical Sciences107031 MoscowRussia

This review co.siders the physio.o.ical and mo.ecular bio.hemical mechanisms o. bile *** co.po.itio. o. bile and structure o. a bile canaliculus,bio.ynthesis and co.jugatio. o. bile acids,bile pho.pho.ipids,fo.matio. o. bile micellar structures,and entero.epatic circulatio. o. bile acids are *** general,the review fo.uses o. the mo.ecular physio.o.y o. the transpo.ting systems o. the hepato.yte sinuso.dal and apical *** o. physio.o.ical and bio.hemical basis o. bile fo.matio. has implicatio.s fo. understanding the mechanisms o. develo.ment o. patho.o.ical pro.esses,asso.iated with diseases o. the liver and biliary tract.

关键词： Bile acids Bile pho.pho.ipids Bile micelle structures Bile salt transpo.ters