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Air-Resistant Lead Halide Perovskite Nanocrystals Embedded into Polyimide of Intrinsic microporosity

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Energy material Advances 2021年第1期2021卷 120-128页

作者： Haoze Yang Luis Gutiérrez-Arzaluz Partha maity mahmoud AAbdulhamid Jun Yin Yang Zhou Cailing Chen Yu Han Gyorgy Szekely Osman m.Bakr Omar f.mohammed Advanced membranes and Porous materials Center(AmPmC)&KAUST Catalysis Center(KCC) Division of Physical Science and Engineering(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Advanced membranes and Porous materials Center(AmPmC) Division of Physical Science and Engineering(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia KAUST Catalysis Center(KCC) Division of Physical Science and Engineering(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Although cesium lead halide perovskite(CsPbX3,X=Cl,Br,or I)nanocrystals(PNCs)have been rapidly developed for multiple optoelectronic applications due to their outstanding optical and transport properties,their device fabrication and commercialization have been limited by their low structural stability,especially under environmental *** this work,a new approach has been developed to protect the surface of these nanocrystals,which results in enhanced chemical stability and optical *** method is based on the encapsulation of CsPbX3 NCs into a polyimide with intrinsic microporosity(PIm-PI),4,4′-(hexafluoroisopropylidene)diphthalic anhydride reacted with 2,4,6-trimethyl-m-phenylenediamine(6fDATrmPD).The presence of 6fDA-TrmPD as a protective layer can efficiently isolate NCs from an air environment and subsequently enhance their optical and photoluminescence *** specifically,comparing NCs treated with a polymer to as-synthesized nanocrystals after 168 h,we observe that the PL intensity decreased by 70%and 20%for the NCs before and after polymer *** addition,the PNC film with a polymer shows a much longer excited-state lifetime than the as-synthesized nanocrystals,indicating that the surface trap states are significantly reduced in the treated *** enhancement in chemical and air stability,as well as optical behavior,will further improve the performance of CsPbBr3 PNCs yielding promising optical devices and paving the way for their production and implementation at a large scale.

关键词： stability porosity yielding

Bone Regeneration Based on Tissue Engineering Conceptions – A 21st Century Perspective

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Bone Research 2013年第3期1卷 216-248页

作者： Jan Henkel maria A.Woodruff Devakara R.Epari Roland Steck Vaida Glatt Ian C.Dickinson Peter f.m.Choong michael A.Schuetz Dietmar W.Hutmacher Institute of Health & Biomedical Innovation Queensland University of TechnologyBrisbane Queensland Australia Orthopaedic Oncology Service Princess Alexandra HospitalBrisbane Australia Department of Surgery University of Melbourne St. Vincent's HospitalMelbourne Australia Department of Orthopaedics St. Vincent's HospitalMelbourneAustralia Bone and Soft Tissue Sarcoma Service Peter MacCallum Cancer CentreMelbourne Australia Orthopaedic and Trauma Services Princess Alexandra HospitalBrisbane Australia George W Woodruff School of mechanical Engineering Georgia Institute of TechnologyAtlanta GA USA

The role of Bone Tissue Engineering in the field of Regenerative medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. Recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive （second generation） biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. future generations of biomaterials （third generation） are designed to be not only osteo- conductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineer- ing and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental ＂origin＂ require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.

关键词： bone tissue engineering regenerative medicine additve manufacturing clinical translation scaffolds

A computational study of the role of particle size standard deviation on the collision frequency in differential settling

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International Journal of Sediment Research 2013年第1期28卷 34-45页

作者： C.HEILIGER N.B.KAYE f.Y.TESTIK Civil Engineering Clemson UniversityClemsonSC29634USA

The results of a simple computational model for differential settling are presented illustrating the significant role that particle size distribution plays in collision frequency and sedimentation rate of particles in a quiescent environment. The model tracks a large number of particles（order 10;） with log-normally distributed diameters,as they settle at their Stokes settling *** collisions are detected and result in larger particles that fall more rapidly.A number of simplifying assumptions are made in the model in order to avoid empirical correlations for phenomena such as collision efficiency and particle *** simplifying assumptions were needed to isolate and quantify the role of the particle size *** concentration profiles indicate that,even in the absence of collisions, the standard deviation（σ;） of the particle size strongly influences the bulk mass settling rate as,for largerσ;, more mass is concentrated in larger,faster falling *** collision frequency is also a strong function ofσ;. for a given mass concentration the collision frequency first increases linearly with increasingσ;as greater variation in particle size leads to greater variation in particle velocity,and shorter times for particles to catch each *** largerσ;more mass is concentrated in larger particles,so,for a given mass concentration,there are fewer particles per unit volume,increasing the mean distance between the particles and reducing the collision *** implications of these results for sedimentation measurement using optical attenuation techniques are discussed.

关键词： Settling Sediment size distribution Sediment collision frequency Coefficient of variation

microwave-Assisted Preparation of CdS Nanoparticles in a Halide-free Ionic Liquid and Their Photocatalytic Activities

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催化学报 2011年第6期32卷 933-938页

作者： m.ESmAILI A.HABIBI-YANGJEH Department of Chemistry Faculty of ScienceUniversity of Mohaghegh Ardabili

A microwave-assisted (4-6 min) method was used for the preparation of CdS nanoparticles in 1-ethyl-3-methylimidazolium ethyl sulfate,a halide-free room-temperature ionic liquid (RTIL).The samples were characterized by powder X-ray diffraction,energy dispersive X-ray spectroscopy,and scanning electron *** reflectance spectra showed a 1.33 eV blue shift relative to bulk *** photocatalytic activities of the nanoparticles for photodegradation of methylene blue (mB) using UV and visible light were *** photodegradation of mB decreased with calcination *** order rate constants for the reaction under visible and UV irradiations over the nanoparticles prepared in the RTIL rich media were 5.4 and 2.5 higher,respectively,than the sample prepared in water.

关键词：固体超强碱氧化钙硝酸钾氧化铝氧化锆氢氧化钾硝酸钙

Solid-State Interfacial Reaction between Eutectic Au-Ge Solder and Cu/Ni(P)/Au metalized Ceramic Substrate and Its Suppression

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Journal of materials Science & Technology 2015年第5期31卷 445-452页

作者： f.Q.Lang H.Yamaguchi H.Nakagawa H.Sato Advanced Power Electronics Research Center(ADPERC) National Institute of Advanced Industrial Science and Technology(AIST).Central 21-1-1UmezonoTsukubaIbaraki 305-8568.Japan

Eutectic Au-12 Ge solder was employed to bond the SiC power devices to a Si3N4/Cu/Ni（P）/Au multilayered *** high-temperature reliability of the bond was investigated in detail at 200,250,300 and 330 ℃,*** and Ni5Ge3intermetallic compounds（ImCs） were identified at the Au-12Ge/Ni（P） interface by micro X-ray diffraction（μXRD） and scanning electron microscopy（SEm）equipped with energy dispersive X-ray analysis（EDX）.The growth of the Ni-Ge ImCs was dominated by Ni5Ge3layer,which formed at the Ni5Ge3/NiGe interface by outward diffusion of Ni from the Ni（P） *** activation energy of the total Ni-Ge ImCs growth was 66 kJ/*** shear strength of the bond was tested at both 25 ℃ and the aging temperatures,*** shear strength decreased slightly after aging at 200 and 250 ℃.The shear strength tested at 250 ℃ was 46 mPa after aging at 250 ℃ for 3000 *** shear strength aged at 300 and 330 ℃ rapidly decreased with aging time due to the rapid growth of the *** slow down the interfacial reaction between the high temperature solder and the Ni（P）layer,an approximately 200 nm-thick Ta/TaN/Ta new diffusion barrier（DB） was deposited on the *** by transmission electron microscopy（TEm） equipped with EDX,reveals that the Ta/TaN/Ta DB was bonded well to the Ni（P） layer and the *** temperature storage test at 330 ℃ for1500 h reveals that the bond of the SiC devices maintained its high shear strength of approximately56 mPa without *** new DB effectively suppressed the interfacial reaction between the Au-12 Ge solder and the Ni（P） layer of the substrate.

关键词： High-temperature solder Interfacial reaction Activ

A Novel Design and fabrication of magnetic Random Access memory Based on Nano-ring-type magnetic Tunnel Junctions

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Journal of materials Science & Technology 2007年第3期23卷 304-306页

作者： X.f.Han H.X.Wei Z.L.Peng H.D.Yang J.f.feng G.X.Du Z.B.Sun L.X.Jiang Q.H.Qin m.ma Y.Wang Z.C.Wen D.P.Liu W.S.Zhan State Key Laboratory of magnetism Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Science Beijing 100080 China

Nano-ring-type magnetic tunnel junctions （NR-mTJs） with the layer structure of Ta（5）/Ir22mn78（10）/ Co75fe25（2）/Ru（0.75）/Cooofe20B20（3）/Al（0.6）-oxide/Co60fe20B20（2.5）/Ta（3）/Ru（5）（thickness unit： nm） were nano-fabricated on the Si（100）/SiO2 substrate using magnetron sputtering deposition combined with the optical lithography, electron beam lithography （EBL） and Ar ion-beam etching techniques. The smaller NR-mTJs with the inner- and outer-diameter of around 50 and 100 nm and also their corresponding NR-mTJ arrays were nano-patterned. The tunnelling magnetoresistance （TmR ＆ R） versus driving current （I） loops for a spin-polarized current switching were measured, and the TmR ratio of around 35% at room temperature were observed. The critical values of switching current for the free Co60fe20B20 layer relative to the reference Co6ofe2oB2o layer between parallel and anti-parallel magnetization states were between 0.50 and 0.75 mA in such NR-mTJs. It is suggested that the applicable mRAm fabrication with the density and capacity higher than 256 mbit/inch2 even 6 Gbite/inch2 are possible using both I NR-mTJ＋1 transistor structure and current switching mechanism based on based on our fabricated 4×4 mRAm demo devices.

关键词： Nano-ring-type magnetic tunnel junctions NR-mTJ mRAm spin polarization Spin transfer effect

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弯晶X射线光学(英文)

光学精密工程 2007年第12期15卷 1823-1828页

作者： E frster Institute for Optics and Quantum Electronics friedrich Schiller University Jena1 Max Wien Platz 07743 Jena Germany

近年来,人们付出很大精力研制新的具有独特性能的同步辐射装置和自由电子激光器,而飞秒激光等离子源可提供具有高峰值亮度的超短X射线脉冲,用来作为波荡器辐射的补充X射线源。此外,所有最新型的X射线源的诊断和应用也都需要专用X射线光... 详细信息

近年来,人们付出很大精力研制新的具有独特性能的同步辐射装置和自由电子激光器,而飞秒激光等离子源可提供具有高峰值亮度的超短X射线脉冲,用来作为波荡器辐射的补充X射线源。此外,所有最新型的X射线源的诊断和应用也都需要专用X射线光学元件或仪器。X射线光谱测量是激光聚变应用中最重要的等离子诊断方法之一,该方法根据实验目的,可获得单色X射线图像或与空间或时间分辨相组合的高分辨率图像。已经研制出拥有多达10个环状弯晶的高精单色成像仪,用以研究激光聚变实验中的内爆过程并通过获得的数据对等离子体参数的时间分辨图做出评估。大功率飞秒激光器可提供实用的相对价格不高的大功率X射线脉冲源,但需要有发光效率,能量分布,以及热电子传输方面的信息来实现理想K层辐射线或者连续X射线输出的最大化,以便得到相当于同步辐射输出的峰值亮度。把这些新的射线源与弯晶光学元件相组合,可完成亚皮秒时间量级的衍射实验。激光泵浦的X射线探针实验已经展示了若干晶体在250 fs内的结构变化。作者所在研究所使用光线追踪和布拉格反射方法设计了1D或2D或1D与2D结合的弯晶X射线光学仪器。在仪器制备过程中,非常注重晶体完整,反射选择的优化,弯曲精确,以及成像和反射特性的测量,还使用X射线形貌相机和衍射仪对分析器晶体的相关特性做了测试。

关键词： X射线光学弯晶 X射线诊断激光产生等离子体 X射线衍射

Density of Liquid Ni-Cr Alloy

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Journal of materials Science & Technology 2003年第1期19卷 16-18页

作者： f.XiaoJoining and Welding Research Institute, Osaka University, Osaka 567-0047, Japan Joining and Welding Res. Inst. Osaka Univ. Osaka 567-0047 Japan

The density of liquid Ni-Cr alloy was measured by a modified sessile drop method. The density of liquid Ni-Cr alloywas found to decrease with increasing temperature and Cr concentration in the alloy. The molar volume of liquidNi-Cr alloy increases with increasing the Cr concentration in the alloy. The molar volume of Ni-Cr alloy determinedin the present work shows a positive deviation from the linear molar volume.

关键词： Ni-Cr alloy Density modified sessile drop method

Investigation of electrophysical, photo- and gas-sensitive properties of ZnO–SnO_(2) sol–gel fflms

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Journal of Advanced Dielectrics 2024年第1期14卷 42-50页

作者： Irina A.Gulyaeva Alexandra P.Ivanisheva maria G.Volkova Victoria Yu.Storozhenko Soslan A.Khubezhov Ekaterina m.Bayan Victor V.Petrov Research and Education Centre“microsystem Technics and multisensory monitoring Systems”Southern federal University Russia Department of Chemistry Southern Federal UniversityRussia Department of Physics North-Ossetian State University362025 VladikavkazRussia Department of Physics and Engineering ITMO University191002 PetersburgRussia

Thin nanocomposite fflms based on tin dioxide with a low content of zinc oxide(0.5–5 mol.%)were obtained by the sol–gel *** synthesized fflms are 300–600 nm thick and contains pore sizes of 19–29 *** resulting ZnO–SnO_(2) fflms were comprehensively studied by atomic force and Kelvin probe force microscopy,X-ray diffraction,scanning electron microscopy,and high-resolution X-ray photoelectron spectroscopy *** photoconductivity parameters on exposure to light with a wavelength of 470 nm were also *** study of the photosensitivity kinetics of ZnO–SnO_(2) fflms showed that the fflm with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time *** of the activation energy of the conductivity,potential barrier,and surface potential of ZnO–SnO_(2) fflms showed that these parameters have maxima at ZnO concentrations of 0.5 mol.%and 1 mol.%.films with 1 mol.%ZnO exhibit high response values when exposed to 5–50 ppm of nitrogen dioxide at operating temperatures of 200℃ and 250℃.

关键词： Sol–gel method,ZnO–SnO_(2) films gas-sensitive properties surface potential potential barrier conduction activation energy