時間:2013年5月22日
地點:北京大學(xué)深圳研究生院G-205
主辦方:新材料學(xué)院
講座(一)Tittle: Understanding and Manipulating Thermal Transport in Polymers
報告人: Tengfei Luo, Aerospace and Mechanical Engineering, University of Notre Dame
時間:2013年5月22日上午10:30-11:30
Abstract:
Polymers, usually known as thermal insulators, can have amazing thermal transport properties depending on their morphology. In this talk, we will discuss a series of atomistic simulations of thermal transport in polymers. We will first discuss how polyethylene molecules can be re-formed into highly aligned forest through self-assembling to conduct heat across two solid substrates efficiently. The results show the promise of polyethylene in thermal interface material applications and implies the strategy of reforming polymers into thermal conductors. We will then discuss the results on Polydimethylsiloxane (PDMS) – the most widely used thermal interface polymer. The restuls suggest a strong correlation between the molecular morphology and thermal transport properties. Lastly, we will discuss our findings on the morphology-thermal conductivity dependency in polyethylene fibers, and show how we can utilize such a correlation to manipulate thermal conductivity through temperature, strain and their combination.
Short Bio:
Tengfei Luo obtained his B.S. in Energy and Power Engineering at Xi’an Jiaotong University. He completed his Ph.D. at Michigan State University in 2009 and was a Postdoctoral Associate at MIT (2009-2011). He joined the University of Notre Dame faculty as an assistant professor of Aerospace and Mechanical Engineering in 2012, with an affiliation with the Center of Sustainable Energy at Notre Dame. Dr. Luo’s research area is in energy, with a focus on nanoscale thermal and mass transport and atomistic modeling. He directs the Molecular-level Energy and Mass Transport (MEMT) lab in the department of aerospace and mechanical engineering at Notre Dame. Of special interest to his group are thermal transport across material interfaces, first-principle characterization of phonon transport, and pump-probe measurement of thermal conductivity and interfacial thermal conductance. He is a coworker in a novel water desalination technology called Directional Solvent Extraction. This technology was selected as one of the top ten world-change ideas by Scientific America. His group is combing computation and experiments to optimize the desalination process. He has also coauthored “Handbook of Molecular Dynamics Potential Functions” published by Begell House.
講座(二)鈣化軟骨(Tessellated Cartilage)材料的性能仿真和表征
報告人:劉曉熹 美國加州大學(xué)
時間:2013年5月22日上午11:30-12:30
摘要:
Much of the skeleton of sharks, skate and rays (Elasmobranchii) is characterized by a tessellated structure, composed of a shell of small, mineralized plates (tesserae) joined by intertesseral ligaments overlaying a soft cartilage core. Although tessellated cartilage is a defining feature of this group, the significance of this skeletal tissue type — particularly from a mechanical perspective — is unknown.
In present work, a cross-sectional model was developed and validated to analyze the function of intertesseral joints in regulating the stress distribution within tessellated cartilage during bending. More dynamic mechanics of tessellated cartilage were investigated through stress relaxation test and percussion test and analyzed via constitutive models. The results indicate that tessellated structure provides possible advantages including increasing the resistance to fatigue damage, mitigating the risk of tearing under excessive bending loads, improving dynamic stiffness and reducing the risk of failure under impact in certain loading direction. Our study demonstrates a novel structure in manufacturing biomimetic materials with improved strength, durability and stability.
Portable Leave-in-Place Laser Scanning for Fatigue Damage Monitoring
(用于疲勞損傷監(jiān)測的便攜式激光掃描設(shè)備)
A compact leave-in-place laser-scanning device for the detection and monitoring of fatigue damage precursors has been developed. The current device is shown to be capable of detecting fatigue-related changes in the surface bidirectional reflectance distribution (BRDF) of aluminum test samples, and detectable changes in BRDF are measured at a very early stage of fatigue development. The system power requirements are compatible with standard sensor mote architectures that are targeted for multiyear lifetimes without battery replacement.
Short Bio:
Xiaoxi Liu (劉曉熹), PhD
Research Specialist
Department of Chemical Engineering and Materials Science
University of California, Irvine
講座(三)水鋰電池
報告人:吳宇平 教授
時間:2013年5月22日下午15:00-15:30
簡介:
1987-1991年在湘潭大學(xué)化學(xué)系學(xué)習(xí),并分別于1990年、1991年完成了有機化學(xué)和高分子化學(xué)兩個專業(yè)學(xué)士畢業(yè)論文的設(shè)計。1994年畢業(yè)于中國原子能科學(xué)研究院,獲工學(xué)碩士學(xué)位。1997年畢業(yè)于中國科學(xué)院化學(xué)研究所,獲理學(xué)博士學(xué)位。1997-1999年在清華大學(xué)從事博士后研究工作。1999-2001在日本科學(xué)技術(shù)振興事業(yè)團(JST)的資助下到日本早稻田大學(xué)應(yīng)用化學(xué)系工作,并擔任客員研究員。2001-2003年在德國洪堡基金委的資助下到開姆尼茲工業(yè)大學(xué)(原卡爾×馬克思大學(xué))作訪問學(xué)者。2003年8月作為優(yōu)秀人才引進到復(fù)旦大學(xué)化學(xué)系,聘為教授。
目前已在國際、國內(nèi)核心刊物上已經(jīng)發(fā)表了論文60余篇,其中SCI刊物30多篇,EI收錄15篇。并在國際、國內(nèi)會議上發(fā)表論文19次,其中2次為大會邀請報告。申請中國發(fā)明專利4項,其中3項已經(jīng)獲得了授權(quán)。
目前的主要研究領(lǐng)域:嵌入(插入,intercalation)電極反應(yīng)動力學(xué);固體電解質(zhì);固態(tài)鋰離子電池;納米材料在儲能材料中的應(yīng)用;微型電池及其材料制備。在很多參加主持國內(nèi)和國際的學(xué)術(shù)會議。
2013年,最新一期《自然》(Nature)雜志子刊《科學(xué)報道》(Sci.Report)刊發(fā)了復(fù)旦大學(xué)教授吳宇平課題組的一項重磅研究成果。
講座(四):鋰磷電池
報告人:何向明
時間:2013年5月22日下午15:30-16:00
簡介:
清華大學(xué)核能與新能源技術(shù)研究院新型能源與材料化學(xué)研究室主任,博士生導(dǎo)師。清華大學(xué)化工系畢業(yè),獲學(xué)士和碩士學(xué)位,2007年在核研院獲在職博士學(xué)位。從事鋰離子電池及其材料研發(fā)及產(chǎn)業(yè)化工作。1989年進入清華大學(xué)核研院工作至今。期間1992-1993到德國進修1年。1997年核研院成立新型能源與材料化學(xué)研究室,任研究室副主任,2008年起任主任。在先進電池及其關(guān)鍵材料領(lǐng)域中有15年的研發(fā)和工程經(jīng)驗。主持研究課題主要來自973、科技部國際合作、國家專項和企業(yè)等,共30多項。主持包括鋰離子電池材料、鋰離子動力電池在內(nèi)的多項產(chǎn)業(yè)化工作。申請發(fā)明專利100多項,其中申請美國日本發(fā)明專利40多項,已獲授權(quán)中國發(fā)明專利30項。在國外期刊上發(fā)表論文110多篇,國內(nèi)期刊上發(fā)表論文80余篇。其中SCI檢索收錄140篇、EI檢索收錄108篇。
主要學(xué)術(shù)貢獻:
2003年至今,圍繞鋰離子電池的電性能及安全性重大需求,以材料化學(xué)為核心、通過多學(xué)科協(xié)同的創(chuàng)新解決關(guān)鍵材料、關(guān)鍵設(shè)計及關(guān)鍵技術(shù)。
(1) 研發(fā)出了新型高比容量負極材料及規(guī)模化制備技術(shù),即聚丙烯腈低溫?zé)峤鈴?fù)合法制備納米合金負極材料和原位碳熱還原法制備球狀微納包埋合金負極材料;
(2) 研發(fā)出系列聚合物基高穩(wěn)定性電解質(zhì),提出了相轉(zhuǎn)移法制備凝膠聚合物電解質(zhì)的新技術(shù),設(shè)計并合成出星形及梳狀聚合物電解制添加劑;
(3) 研發(fā)出了氧化物正極材料的安全性改性技術(shù),通過吸附反應(yīng)技術(shù)實現(xiàn)了納米非晶層對氧化物顆粒的完整包覆,克服了現(xiàn)有顆粒堆積包覆技術(shù)對材料性能造成的影響;
(4) 研發(fā)出了高安全性、長壽命鋰離子電池技術(shù)體系,集成課題組及國際上在材料、電池結(jié)構(gòu)、電池管理等方面的創(chuàng)新成果,攻克了大型安全性動力電池制備及應(yīng)用的關(guān)鍵難題;
(5) 設(shè)計提出新型硫基電池結(jié)構(gòu),通過研發(fā)預(yù)鋰化技術(shù),回避金屬鋰負極的使用,解決了現(xiàn)有鋰硫電池電性能差及安全性能的巨大缺陷;
(6) 在國際上率先提出以低成本的紅磷為儲鋰負極材料、并開展了無機/高分子雜化硫基儲鋰正極材料的研究,研究結(jié)果發(fā)表在Angew. Chem. Int. Ed.(IF=13.4)等領(lǐng)域一級刊物上, 6項發(fā)明專利已獲授權(quán);
(7) 研發(fā)出高性能磷酸鐵鋰可規(guī)模化制備技術(shù),實現(xiàn)了納米片自組裝高密度球形磷酸鐵鋰的可控制備,提出了納米片狀及多級結(jié)構(gòu)磷酸鐵鋰的制備技術(shù)及工藝,產(chǎn)品電化學(xué)性能優(yōu)異,研究結(jié)果發(fā)表于Nano Lett.(IF=13.2),已申報多項發(fā)明專利。