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Evolution of Morphology and Structure During Crystallization and Melting in Syndiotactic Polypropylene

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应用化学 2001年第5期18卷 280-288页

作者： Zhi-Gang WANG Benjamin S.HSIAO Charles C.HAN State university of New York at stony brook Department of ChemistryStony BrookNY 11794-3400 Polymers Division and Center for Neutron Research National Institute of Standards and TechnologyGaithersburgMD 20899

Structure and morphology development during isothermal crystallization and subsequent melting of syndiotactic polypropylene(sPP) was studied by time-resolved simultaneous small-angle X-ray scattering(SAXS) and wide-angle X-ray diffraction(WAXD) methods with synchrotron radiation and differential scanning calorimetry(DSC). The time and temperature dependent parameters such as long period, L , crystal lamellar thickness, l c, amorphous layer thickness, l a, scattering invariant, Q , crystallinity, X c, lateral crystal sizes, L 200 and L 020 , and unit cell parameters a and b were extracted from SAXS and WAXD profiles. Decreasing long period and crystal thickness indicate that thinner secondary crystal lamellae are formed. The decreases in unit cell parameters a and b during isothermal crystallization process suggest that crystal perfection takes place. The changes in the morphological parameters (the invariant, Q , crystallinity, X c, long period, L , and the crystal thickness, l c) during subsequent melting were found to follow a two-stage melting process, corresponding to the dual endotherm behavior in the DSC scan. We conclude that the dual melting peaks are due to the melting of secondary and primary lamellae(first peak) and the subsequent recrystallization-melting process(second peak). Additional minor endothermic peak located at the lowest temperature was also detected and might be related to melting of secondary, thinner and defective lamellae. WAXD showed that during melting, thermal expansion was greater along the b axis than that along the a axis.

关键词：间规聚丙烯结晶熔化晶体结构 DCS SAXS WAXD

Dynamic ocean inverse modeling based on differentiable rendering

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Computational Visual Media 2024年第2期10卷 279-294页

作者： Xueguang Xie Yang Gao Fei Hou Aimin Hao Hong Qin State Key Lab of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China Qingdao Research Institute Beihang UniversityQingdao 266100Chinaand Peng Cheng LabShenzhen 518000China SKLCS Institute of SoftwareChinese Academy of SciencesBeijing 100190Chinaand University of Chinese Academy of SciencesBeijing 100049China department of Computer Science Stony Brook University(SUNY at Stony Brook)Stony BrookNew York 11794-2424USA

Learning and inferring underlying motion patterns of captured 2D scenes and then re-creating dynamic evolution consistent with the real-world natural phenomena have high appeal for graphics and *** bridge the technical gap between virtual and real environments,we focus on the inverse modeling and reconstruction of visually consistent and property-verifiable oceans,taking advantage of deep learning and differentiable physics to learn geometry and constitute waves in a self-supervised ***,we infer hierarchical geometry using two networks,which are optimized via the differentiable *** extract wave components from the sequence of inferred geometry through a network equipped with a differentiable ocean ***,ocean dynamics can be evolved using the reconstructed wave *** extensive experiments,we verify that our new method yields satisfactory results for both geometry reconstruction and wave ***,the new framework has the inverse modeling potential to facilitate a host of graphics applications,such as the rapid production of physically accurate scene animation and editing guided by real ocean scenes.

关键词： inverse modeling surface reconstruction wave modeling ocean waves differentiable rendering(DR)

Biomaterials for Adhesion in Orthopedic Applications:A Review

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Engineered Regeneration 2020年第1期1卷 51-63页

作者： Younis Zaokari Alicia Persaud Amr Ibrahim Biomedical Engineering department College of Engineering and Applied SciencesStony Brook UniversityUnited States

Adhesive biomaterials,historically,have had a wide range of applications in all medical *** the extensive variety of biomaterials with adhesion properties,the field of orthopedics benefits from using adhesives which can provide superior biocompatibility,resorbability,and low *** goal of this review is to serve as a reference of the types of adhesive biomaterials used clinically and their specific applicability in the field of *** applications of adhesive biomaterials in orthopedics are as scaffolds,filler materials to treat bone defects and as carrier materials to deposit other bioactive materials to a ***,we review the history and background of adhesive biomaterials and some of their general applications in *** we focus on the various types of adhesive biomaterials which include fibrin,collagen,polyurethane,epoxy resin,cyanoacrylates,polyesters and polymethylmethacrylate,all of which are excellent candidates for the field of *** discuss their properties,current applications in all fields,and advantages and disadvantages found in some ***,we indicate some future directions for adhesive biomaterials in orthopedics and highlight their advantages over conventional biomaterials in orthopedics.

关键词： Adhesive biomaterials Orthopedic biomaterials Osteoinduction Polymer-based biomaterials Fibrin biomaterials

Skin-integrated stretchable actuators toward skin-compatible haptic feedback and closed-loop human-machine interactions

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npj Flexible Electronics 2023年第1期7卷 555-566页

作者： Si Chen Yanjun Chen Ji Yang Teng Han Shanshan Yao department of Mechanical Engineering Stony Brook UniversityStony BrookNY 11794USA Institute of Software Chinese Academy of Sciences100190 BeijingChina Meta Platforms Menlo ParkCA 94025USA

Skin-integrated haptic interfaces that can relay a wealth of information from the machine to the human are of great ***,existing haptic devices are not yet able to produce haptic cues that are compatible with the *** this work,we present the stretchable soft actuators for haptic feedback,which can match the perception range,spatial resolution,and stretchability of the ***-amplification structures are fabricated using a scalable self-assembly process to ensure an output pressure beyond the skin perception *** to the minimized device size,the actuator array can be fabricated with a sufficiently high spatial resolution,which makes the haptic device applicable for skin locations with the highest spatial acuity.A haptic feedback system is demonstrated by employing the developed soft actuators and highly sensitive pressure *** proof-ofconcept applications are developed to illustrate the capability of transferring information related to surface textures and object shapes acquired at the robot side to the user side.

关键词： robot Skin stretch

A STUDY OF STRUCTURE AND PROPERTY CHANGES OF BIODEGRADABLE POLYGLYCOLIDE AND POLY(GLYCOLIDE-co-LACTIDE)FIBERS DURING PROCESSING AND IN VITRO DEGRADATION

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Chinese Journal of Polymer Science 2003年第2期21卷 159-167页

作者： Bruce X.Fu Benjamin S.Hsiao Gavin Chen Jack Zhou Susan Lin Jenny Yuan Ilya Koyfman Dennis D Jamiolkowski Edward Dormier department of chemistry State University of New York at Stony Brook Stony BrookNY 11794-3400 USA Ethicon Worldwide A Johnson & Johnson Company P. O. Box 151 Somerville. New Jersey 08876-0151 USA

Structure and properties of bioabsorbable polyglycolide (PGA) and poly(glycolide-co-lactide) (PGA-co-PLA)fibers were investigated during several industrial processing stages and in vitro degradation by means of wide-angle X-raydiffraction (WAXD), dynamic mechanical analysis (DMA) and mechanical property tests. In the orientation stage, the PGAfibers were found to have higher degrees of crystallinity than corresponding PGA-co-PLA samples produced under similarconditions. In the hot-stretching and post-annealing stages, after fibers were braided, PGA samples were found to gain morecrystallinity and higher T_g than PGA-co-PLA samples. The higher crystallinity in PGA fibers resulted in a slower rate ofdegradation. DMA results showed that a great deal of internal stress that was built during orientation and hot-stretchingstages was released in the post-annealing stage for a1l PGA and PGA-co-PLA samples. During earlier stages of in vitrodegradation, both PGA and PGA-co-PLA samples exhibited the typical cleavage-induced crystallization mechanism. Theheat shrinkage in the glass transition area was found to disappear after 6-8 days of degradation for all PGA and PGA-co-PLAsamples, indicating the amorphous portions of the polymers lost orientation after a short period in the buffer solution, mostlikely due to relaxation of the cleaved chains.

关键词： Polyglycolide Poly(glycolide-co-lactide) Bioabsorbable Fiber processing in vitro Degradation

The landscape and flux of a minimum network motif,Wu Xing

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Chinese Physics B 2020年第12期29卷 186-197页

作者： Kun Zhang Ashley Xia Jin Wang State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The U.S.Center for Chinese Medicine by Beijing university of Chinese Medicine 15005 Shady Groove RoadSuite 410RockvilleMD 20850USA department of chemistry and Physics Department of Applied MathematicsState University of New York at Stony BrookStony BrookNY 11794USA

Wu-Xing theory is an ancient philosophy that serves as a guiding principle in the traditional Chinese medicine(TCM).It has been used to explain the unbalance among the TCM organ systems in disease states and provide treatment philosophy *** now,it is still a challenge to explore the Wu-Xing theory beyond its philosophical *** this study,we established a quantitative framework using the landscape and flux theory to characterize the nature of the WuXing theory from a perspective of a minimal network motif and leave certain specific functional aspects of Wu-Xing theory for future *** uncovered the irregular ring shape of projection landscape for the Wu-Xing network with several local basins and *** found that the dynamics of the self-organized Wu-Xing system was determined by the underlying negative landscape gradient force and the nonequilibrium rotational *** the shape of the WuXing landscape determines the stabilities of the states,the rotational flux guarantees the persistent periodic oscillation and the stability of the *** provides a physical and quantitative basis for Yin–Yang duality of the driving forces for determining the dynamics and behaviors of the living *** landscape and flux analysis,we can identify the key parameter for the dynamics/function of Wu-Xing *** findings allow us to have a deeper understanding of the scientific merits of the ancient Wu-Xing theory from the network motif perspective.

关键词： traditional Chinese medicine nonequilibrium landscapes flux

Quantum computing in power systems

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iEnergy 2022年第2期1卷 170-187页

作者： Yifan Zhou Zefan Tang Nima Nikmehr Pouya Babahajiani Fei Feng Tzu-Chieh Wei Honghao Zheng Peng Zhang department of Electrical and Computer Engineering Stony Brook UniversityStony BrookNY 11794USA Interdisciplinary Science Depart-ment Brookhaven National LaboratoryUptonNY 11973USA CN Yang Institute for Theoretical Physics and department of Physics and Astronomy Stony Brook UniversityStony BrookNY 11794USA Smart Grid and Technology Commonwealth EdisonOakbrookIL 60523USA

Electric power systems provide the backbone of modern industrial *** scalable grid analytics is the keystone to successfully operating large transmission and distribution ***,today’s power systems are suffering from ever-increasing computational burdens in sustaining the expanding communities and deep integration of renewable energy resources,as well as managing huge volumes of data *** unprecedented challenges call for transformative analytics to support the resilient operations of power ***,the explosive growth of quantum computing techniques has ignited new hopes of revolutionizing power system *** computing harnesses quantum mechanisms to solve traditionally intractable computational problems,which may lead to ultra-scalable and efficient power grid *** paper reviews the newly emerging application of quantum computing techniques in power *** present a comprehensive overview of existing quantum-engineered power analytics from different operation perspectives,including static analysis,transient analysis,stochastic analysis,optimization,stability,and *** thoroughly discuss the related quantum algorithms,their benefits and limitations,hardware implementations,and recommended *** also review the quantum networking techniques to ensure secure communication of power systems in the quantum ***,we discuss challenges and future research *** paper will hopefully stimulate increasing attention to the development of quantum-engineered smart grids.

关键词： Quantum computing power system variational quantum algorithms quantum optimization quantum machine learning quantum security

Understanding Interfacial chemistry Interactions in Energy-Dense Lithium-Ion Electrodes

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Accounts of Materials Research 2023年第2期4卷 156-167页

作者： Donghee Gueon Miguel A.Gonzalez Kenneth J.Takeuchi Esther S.Takeuchi Amy C.Marschilok Elsa Reichmanis department of Chemical and Bimolecular Engineering Lehigh UniversityBethlehemPennsylvania 18015United States School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGeorgia 30332United States Interdisciplinary Science department Brookhaven National LaboratoryUptonNew York 11973United States Institute for Energy Sustainability and Equity Stony Brook UniversityStony BrookNew York 11794United States department of Material Science and Chemical Engineering Stony Brook UniversityStony BrookNew York 11794United States department of chemistry Stony Brook UniversityStony Brook 11794United States

For the past two decades,conversion and alloying-type materials have been heralded as the natural heir to commercially available graphite anodes due to their ability to deliver high gravimetric/volumetric *** of batteries with these high-energy-density active materials could impact a variety of sectors including electric vehicles,grid storage,and consumer electronics and contribute toward an ever-increasing electrified ***,the various failure mechanisms from inherent interfacial chemical instabilities associated with these materials make them unable to be merely substituted into currently available electrode fabrication and formulation processing *** a result,realizing the high theoretical capacity and achieving commercial viability of these materials will rely on the careful manipulation of interfacial chemical interactions that dictate and control various kinetic and transport processes across multiple scales of the composite *** has led to a plethora of research that has focused on systematically understanding properties of the different electrode components and designing carefully constructed electrode formulations to achieve composite electrodes with increased chemical stability,enhanced local mixed conductivities,or improved mechanical *** Account relates recent progress in the understanding of synergetic opportunities for energy-dense,resilient composite *** understanding the interplay between components of the composite electrode,we can construct enhanced well-integrated electrodes with performance metrics that surpass empirically derived *** to the increased complexity of high-volume-expanding electrodes,performance is more than the cumulative contributions of the individual components,and therefore energy and compatibility matching are important for robust electrochemical performance across cycling,rate capability,facile lithium-ion transport,and *** this Account,sy

关键词： composite interfacial electrode

A MATHEMATICAL THEORY FOR LES CONVERGENCE

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Acta Mathematica Scientia 2012年第1期32卷 237-258页

作者： H.Lim T.Kaman V.Mahadeo J.Glimm S.Dutta D.H.Sharp B.Plohr department of Applied Mathematics and Statistics Stony Brook University College of St.Catherine Los Alamos National Laboratory

Practical simulations of turbulent processes are generally cutoff, with a grid resolution that stops within the inertial range, meaning that multiple active regions and length scales occur below the grid level and are not resolved. This is the regime of large eddy simulations （LES）, in which the larger but not the smaller of the turbulent length scales are resolved. Solutions of the fluid Navier-Stokes equations, when considered in the inertial regime, are conventionally regarded as solutions of the Euler equations. In other words, the viscous and diffusive transport terms in the Navier-Stokes equations can be neglected in the inertial regime and in LES simulations, while the Euler equation becomes fundamental. For such simulations, significant new solution details emerge as the grid is refined. It follows that conventional notions of grid convergence are at risk of failure, and that a new, and weaker notion of convergence may be appropriate. It is generally understood that the LES or inertial regime is inherently fluctuating and its description must be statistical in nature. Here we develop such a point of view systematically, based on Young measures, which are measures depending on or indexed by space time points. In the Young measure du（ξ）x,t, the random variable ξ of the measure is a solution state variable, i.e., a solution dependent variable, representing momentum, density, energy and species concentrations, while the space time coordinates, x, t, serve to index the *** evidence suggests that convergence via Young measures is suifficiently weak to encompass the LES/inertial regime; numerical and theoretical evidence suggests that this notion may be required for passive scalar concentration and therm degrees of freedom. Our objective in this research is twofold： turbulent simulations without recourse to ad- justable parameters （calibration） and extension to more complex physics, without use of additional models or parameters, in both cases with

关键词： numerical methods turbuent mixing