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高组分稀磁半导体Cd_(1 -x)Mn_xTe/CdTe超晶格的光调制反射谱研究

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红外与毫米波学报 2002年第5期21卷 332-336页

作者：陈辰嘉王学忠梁晓甘李海涛凌震王迅 V Bellani M Geddo A Stella S Tavazzi A Borghesi A Sassella 北京大学物理系北京100871 复旦大学应用表面物理实验室上海200433 INFM-dipartimento di Fisica"A.Volta"dell’Universitiy di pavia INFM-dipartimento di scienza dei materiali University di Milano Bicocca milanoitaly20125

报道用分子束外延 (MEB)技术生长的x =0 4 ,0 8的高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格的光调制反射谱在室温和液氮下的实验结果 .观测到 11H ,2 2H ,33H和 11L等激子跃迁结构 ,计及子能级的量子限定效应和晶格失配导致的应力效应 ... 详细信息

报道用分子束外延 (MEB)技术生长的x =0 4 ,0 8的高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格的光调制反射谱在室温和液氮下的实验结果 .观测到 11H ,2 2H ,33H和 11L等激子跃迁结构 ,计及子能级的量子限定效应和晶格失配导致的应力效应 ,对子能级结构进行了计算 ,除x =0 8样品的 33H能量计算值与实验值有较大偏差外 ,实验结果与理论符合得很好 .还与光致发光谱实验结果进行了比较 .

关键词：光调制反射激子跃迁应力效应超晶格

Screw dislocation structure and mobility in body centered cubic Fe predicted by a Gaussian Approximation Potential

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npj Computational Materials 2018年第1期4卷 90-96页

作者： Francesco Maresca Daniele Dragoni Gábor Csányi Nicola Marzari William A.Curtin Laboratory for Multiscale Mechanics Modeling(LAMMM) Institute of Mechanical EngineeringÉcole Polytechnique Fédérale de LausanneLausanne CH-1015Switzerland Theory and Simulation of Materials(THEOS) and National Centre for Computational Design and Discovery of Novel Materials(NCCR MARVEL)École Polytechnique Fédérale de LausanneLausanne CH-1015Switzerland dipartimento di scienza dei materiali Universitàdi Milano-BicoccaVia R.Cozzi 55Milan I-20125Italy Department of Engineering University of CambridgeTrumpington StreetCambridge CB21PZUK

The plastic flow behavior of bcc transition metals up to moderate temperatures is dominated by the thermally activated glide of screw dislocations,which in turn is determined by the atomic-scale screw dislocation core structure and the associated kink-pair nucleation mechanism for *** complex plasticity phenomena requires the simulation of many atoms and interacting dislocations and *** sizes are beyond the scope of first-principles methods and thus require empirical interatomic *** for the technological important case of bcc Fe,existing empirical interatomic potentials yield spurious ***,the structure and motion of the screw dislocations in Fe are studied using a new Gaussian Approximation Potential(GAP)for bcc Fe,which has been shown to reproduce the potential energy surface predicted by density-functional theory(DFT)and many associated *** Fe GAP predicts a compact,non-degenerate core structure,a single-hump Peierls potential,and glide on{110},consistent with DFT *** thermally activated motion at finite temperatures occurs by the expected kink-pair nucleation and propagation *** stress-dependent enthalpy barrier for screw motion,computed using the nudgedelastic-band method,follows closely a form predicted by standard theories with a zero-stress barrier of~1 eV,close to the experimental value of 0.84 eV,and a Peierls stress of~2 GPa consistent with DFT predictions of the Peierls potential.

关键词： structure dislocation cubic

Intrinsic and Extrinsic Exciton Recombination Pathways in AgInS_(2)Colloidal Nanocrystals

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Energy Material Advances 2021年第1期2021卷 165-174页

作者： Matteo L.Zaffalon Valerio Pinchetti Andrea Camellini Sergey Vikulov Chiara Capitani Bing Bai Meng Xu Francesco Meinardi Jiatao Zhang Liberato Manna Margherita Zavelani-Rossi Scott A.Crooker Sergio Brovelli dipartimento di scienza dei materiali Universitàdegli studi di Milano-Bicoccavia Roberto Cozzi 5520125 MilanoItaly dipartimento di Energia Politecnico di MilanoVia Ponzio 34/320133 MilanoItaly Istituto Italiano di Tecnologia Via Morego 3016163 GenovaItaly Glass to Power SpA Via Fortunato Zeni 838068 RoveretoItaly Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China IFN-CNR Piazza Leonardo da Vinci 3220133 MilanoItaly National High Magnetic Field Laboratory Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA

Ternary I-III-VI2 nanocrystals(NCs),such as AgInS_(2) and CuInS_(2),are garnering interest as heavy-metal-free materials for photovoltaics,luminescent solar concentrators,LEDs,and *** origin of the emission and absorption properties in this class of NCs is still a subject of *** theoretical and experimental studies revealed that the characteristic Stokesshifted and long-lived luminescence of stoichiometric CuInS_(2) NCs arises from the detailed structure of the valence band featuring two sublevels with different *** same valence band substructure is predicted to occur in AgInS_(2) NCs,yet no experimental confirmation is available to ***,we use complementary spectroscopic,spectro-electrochemical,and magneto-optical investigations as a function of temperature to investigate the band structure and the excitonic recombination mechanisms in stoichiometric AgInS_(2) *** transmission measurements reveal the signatures of two subbands with opposite parity,and photoluminescence studies at cryogenic temperatures evidence a dark state emission due to enhanced exchange interaction,consistent with the behavior of stoichiometric CuInS_(2) *** the temperature as well as applying reducing electrochemical potentials further suppress electron trapping,which represents the main nonradiative channel for exciton decay,leading to nearly 100%emission efficiency.

关键词： parity valence applying

Perovskite Semiconductor Nanocrystals

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Energy Material Advances 2022年第1期2022卷 273-274页

作者： Liberato Manna Osman M.Bakr Sergio Brovelli Hongbo Li Nanochemistry Department Istituto Italiano di TecnologiaVia Morego 3016163 GenovaItaly Advanced Membranes and Porous Materials Center KAUST Catalysis CenterDivision of Physical Science and EngineeringKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia dipartimento di scienza dei materiali Universitàdegli Studi di Milano-BicoccaVia Cozzi 55IT-20125 MilanoItaly Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green ApplicationsExperimental Center of Advanced Materials School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

The world is facing the grand challenges of balancing economic growth and environmental protection,urging the development of sustainable energy sources and more efficient energy consumption[1].To tackle these challenges,new materials are in great *** this respect,semiconductor nanocrystals(NCs)have shown great potential in light harvesting applications such as photovoltaics.

关键词： harvesting challenges balancing

Nanoparticles Production and Inclusion in <i>S. aureus</i>Incubated with Polyurethane: An Electron Microscopy Analysis

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Open Journal of Medical Imaging 2013年第2期3卷 69-73页

作者： Lyubov V. didenko George A. Avtandilov Natalia V. Shevlyagina N. M. Shustrova Tatiana A. Smirnova I. Y. Lebedenko Roberta Curia Claudio Savoia Francesco Tatti Marziale Milani dipartimento di scienza dei materiali Università degli Studi di Milano-Bicocca Via Cozzi Milano Italy FEI Italia Viale Bianca Maria Milano Italy Gamaleya Research Institute for Epidemiology and Microbiology Gamaleya ul. Moscow Russia Moscow State Medical and Stomatological University Moscow Russia ST Microelectronics Via C. Olivetti Agrate Brianza (Mi) Italy

This study shows that submicron/nanoparticles found in bacterial cells (S. aureus) incubated with polyurethane (a material commonly used for prostheses in odontostomatology) are a consequence of biodestruction. The presence of polyurethane nanoparticles into bacterial vesicles suggests that the internalization process occurs through endocytosis. TEM and FIB/SEM are a suitable set of correlated instruments and techniques for this multi facet investigation: polyurethane particles influence the properties of S. aureus from the morpho-functional standpoint that may have undesirable effects on the human body. S. aureus and C. albicans are symbiotic microorganisms;it was observed that C. albicans has a similar interaction with polyurethane and an increment of the biodestruction capacity is expected by its mutual work with S. aureus.

关键词： Polyurethane S. aureus Biodestruction Endocytosis FIB/SEM (Focused Ion Beam/Scanning Electron Microscope) TEM (Transmission Electron Microscope) STEM (Scanning Transmission Electron Microscope)

Novel method for the identification of the maximum solid loading suitable for optimal extrusion of ceramic pastes

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Journal of Advanced Ceramics 2014年第1期3卷 7-16页

作者： Andrea AZZOLINI Vincenzo M.SGLAVO John A.DOWNS Department of Industrial Engineering Universitàdi TrentoVia Mesiano 7738123TrentoItaly

Gadolinia-doped ceria ceramic pastes were formulated with different solid loadings and extruded using lab-scale *** force to maintain a constant ram speed of 10 mm/min was *** radial shrinkage after drying was proportional to the solid loading and this allowed the determination of the maximum solid loading by an extrapolation *** order to obtain the apparent viscosity of the pastes,a novel approach based on the analysis of the slope of the extrusion pressure plot versus distance covered by the ram,was formulated for the direct determination of the shear stress upon *** agreement of the determined maximum solid loading with values calculated by two existing models confirmed that the proposed approach was an alternative and reliable method to identify the upper limit of the solid loading range for the formulation of extrudable ceramic pastes.

关键词： ceramic extrusion maximum solid loading drying shrinkage rheology

原位生成白炭黑对异戊橡胶补强性能与其制备方法和结构的相互关系

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轮胎工业 2012年第11期32卷 675-683页

作者： F.Bignotti S.Borsacchi R.de Santis M.Geppi M.Messori U.P.Sudhakaran 肖大玲(摘译) 刘俊杰(校) Università degli Studi di Brescia Via Branze 38Brescia 25123Italy Università di Pisa Via Risorgimento 35Pisa 56126Italy Consorzio Interuniversitario Nazionale per la scienza e Tecnologia dei materiali INSTMVia G.Giusti 9Firenze 50121Italy Università degli Studi di Modena e Reggio Emilia Via Vignolese 905/AModena 41125Italy 北京橡胶工业研究设计院中化化工科学技术研究总院

弹性体一般需要添加补强填料以提高其基本性能而得到商业应用。炭黑和白炭黑是应用最广的橡胶补强填料。一般说来,与炭黑填充胶料相比,白炭黑填充胶料的撕裂强度较大、耐磨性能和耐老化性能较好。此外,在轮胎工业中,当炭黑补强和白炭黑... 详细信息

弹性体一般需要添加补强填料以提高其基本性能而得到商业应用。炭黑和白炭黑是应用最广的橡胶补强填料。一般说来,与炭黑填充胶料相比,白炭黑填充胶料的撕裂强度较大、耐磨性能和耐老化性能较好。此外,在轮胎工业中,当炭黑补强和白炭黑补强的两种轮胎耐磨性能和湿地抓着性能相同时，后者胎面胶的滚动阻力比前者更低。

关键词：补强性能白炭黑制备方法异戊橡胶原位生成橡胶补强填料结构商业应用