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Structural & Magnetic Characterizations of NiLiZn Nanoferrites Synthesized by Co-precipitation Method

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Journal of Materials Science & Technology 2011年第11期27卷 991-995页

作者： d.N. Rohadiana Z.A.Z. Jamal S.B. Jamaludin M.F. Bari J. Adnan Sustainable Engineering Research Cluster Universiti Malaysia Perlis School of Microelectronic Engineering Universiti Malaysia Perlis

Synthesis of ***（0.5-x）Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction （XRd） and vibrating sample magnetometer （VSM） measurements were performed on the samples to determine the characteristics of the crystal structures and the magnetic properties of the samples, respectively. The spinel phase structures of the samples were confirmed by XRd analysis. Patterns of decreased lattice parameter and increased crystallite size values were observed by increasing the Li concentration at longer synthesis reaction periods. Similarly, for the magnetic properties, both the saturation magnetization （Ms） and coercivity （Hc） were found to vary with increasing patterns at higher Li doping levels and longer synthesis reaction periods. The results and mechanisms concerned were discussed.

关键词： Lithium nickel zinc ferrite Co-precipitation Crystal structure Magnetic properties

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Radix-8复数除法器的设计与实现

西安交通大学学报 2009年第10期43卷 1-6页

作者：王东郑南宁 Milos d．ERCEGOVAC 西安交通大学电子与信息工程学院西安710049 加州大学洛杉矶分校计算机科学系美国洛杉矶90024

设计了一种高性能、低功耗的Radix-8时序复数除法器.该复数除法器采用了逐位递归算法和操作数预变换技术,并在传统结构的基础上,选用冗余形式保留预校正变量,节省了超长进位加法器的使用,缩短了关键路径的延时.设计还通过实部和虚部商... 详细信息

设计了一种高性能、低功耗的Radix-8时序复数除法器.该复数除法器采用了逐位递归算法和操作数预变换技术,并在传统结构的基础上,选用冗余形式保留预校正变量,节省了超长进位加法器的使用,缩短了关键路径的延时.设计还通过实部和虚部商位的合并以及基于6输入查找表结构的硬件优化,提高了乘加逻辑单元的资源利用率.Stratix-II型现场可编程逻辑器件仿真验证表明,与使用超长进位加法器的传统结构相比,所设计的复数除法器的速度提高了44%,硬件资源减少了31%.

关键词：复数除法器逐位递归算法现场可编程逻辑器件

Evolution in the formation of graphene nanocapsules from coal tar pitch

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International Journal of Coal Science & Technology 2020年第4期7卷 816-824页

作者： d.M.Puente-Siller A.E.Garcia-Castillo J.A.Lopez-Corpus A.Perea-Garduno department of Research and development Altos Hornos de MexicoS.A.B.de C.V.Prolongacion JuarezS/NLa Loma.25770 Monclova.CoahuilaMexico

It has recently been reported that coal tar pitch(CTP)can be utilised as raw material for the production of graphene nanocapsules(GNCs)because it is formed by a great quantity of aromatic organic compounds(which promote the rearrangement of double bonds by a process of polymerisation).due to the importance of graphene and the search for a non-expensive methodology to produce it,this work used CTP to synthesise GNCs using an in situ activation technique at low temperatures and evaluating the effect of the working temperature on the formation of such *** other words,analysing the form of the particle as the temperature rises from 600 to 900℃.As result of the experimentation,powders were obtained and analysed by the techniques of X-Ray diffraction,Raman Spectroscopy and Microscopy,employing Field Fmission Scanning Electron Microscopy by normal mode as well as by Scanning Transmission Electron Microscopy and a High-Resolution Scanning Electron *** results show that working with temperatures between 800 and 850℃promotes the production of GNCs,considering that their size reduces as the working temperature rises.

关键词： Synthesis Nanocapsule Graphene Tar Agglomeration

Meeting report:a hard look at the state of enamel research

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International Journal of Oral Science 2017年第4期9卷 193-199页

作者： ophir d klein olivier duverger wendy shaw rodrigo s lacruz derk joester janet moradian-oldak megan k pugach j timothy wright sarah e millar ashok b kulkarni john d bartlett thomas gh diekwisch pamela den besten james p simmer program in craniofacial biology and department of orofacial sciences university of californiasan franciscoSan FranciscoUSA department of pediatrics and institute for human genetics university of californiasan franciscoSan FranciscoUSA laboratory of skin biology national institute of arthritis and muscular and skin diseasesnational institutes of healthBethesdaUSA physical science division pacific northwest national laboratoriesRichlandUSA department of basic science and craniofacial biology new york university college of dentistryNewYorkUSA department of materials science and engineering northwestern universityevanstonusaEvanstonUSA center for craniofacial molecular biology herman ostrow school of dentistryuniversity of southern californiaLos AngelesUSA the forsyth institute CambridgeUSA department of developmental biology harvard school of dental medicineBostonUSA department of pediatric dentistry university of north caroline school of dentistryChapel HillUSA departments of dermatology and cel&developmental biology perelman school of medicineand department of anatomy&cell biologyschool of dental medicineuniversity of pennsylvaniaPhiladelphiaUSA functional genomics section national institute of dental and craniofacial researchBethesdaUSA division of biosciences ohio state universitycollege of dentistryColumbusUSA department of periodontics and center for craniofacial research and diagnosis texas a&m university college of dentistryDallasUSA center for children’s oral health research and department of orofacial sciences university of californiasan franciscoSan FranciscoUSA biologic and materials sciences and division of prosthodontics university of michiganAnn ArborUSA

The Encouraging Novel Amelogenesis Models and Ex vivo cell Lines （ENAMEL） development workshop was held on 23 June 2017 at the Bethesda headquarters of the National institute of dental and Craniofacial Research （NIdCR）. discussion topics included model organisms, stem cells/cell lines, and tissues/3d cell culture/organoids. Scientists from a number of disciplines, representing institutions from across the United States, gathered to discuss advances in our understanding of enamel, as well as future directions for the field.

关键词： enamel mineralized tissue mineralization ameloblast stem cell

Microglial process convergence on axonal segments in health and disease

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Neuroimmunology and Neuroinflammation 2020年第1期7卷 23-39页

作者： Savannah d.Benusa Audrey d.Lafrenaye department of Anatomy and Neurobiology Virginia Commonwealth UniversityRichmondVA 23298USA

Microglia dynamically interact with neurons influencing the development, structure, and function of neuronal networks. Recent studies suggest microglia may also influence neuronal activity by physically interacting with axonal domains responsible for action potential initiation and propagation. However, the nature of these microglial process interactions is not well understood. Microglial-axonal contacts are present early in development and persist through adulthood, implicating microglial interactions in the regulation of axonal integrity in both the developing and mature central nervous system. Moreover, changes in microglial-axonal contact have been described in disease states such as multiple sclerosis (MS) and traumatic brain injury (TBI). depending on the disease state, there are increased associations with specific axonal segments. In MS, there is enhanced contact with the axon initial segment and node of Ranvier, while, in TBI, microglia alter interactions with axons at the site of injury, as well as at the axon initial segment. In this article, we review the interactions of microglial processes with axonal segments, analyzing their associations with various axonal domains and how these interactions may differ between MS and TBI. Furthermore, we discuss potential functional consequences and molecular mechanisms of these interactions and how these may differ among various types of microglial-axonal interactions.

关键词： Microglia multiple sclerosis traumatic brain injury microglia-axonal interactions

Lessons from Rotor 37

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Journal of Thermal Science 1997年第1期6卷 1-13页

作者： J.d. denton(Whittle Laboratory Cambridge University Engineering dept., Cambridge, England) Whittle Laboratory Cambridge University Engineering Dept. Cambridge England

NASA rotor 37 was used as a ’blind’ test case for turbomachinery CFd by the Turbimachinery Com-mittee of the IGTI. The rotor is a transonic compressor with a tip speed of 454 m/s (15OO ft/s) anda relatively high pressure ratio of 2.1. It was tested in isolation with a circumferentially uniform inletflow so that the flow through it should be steady apart from any effects of passage to passage geometry variation and mechanical vibration. As such it represents the simplest possible type of test forthree-dimensional turbomachinery flow solvers. However, the rotor still presents a real challenge to3d viscous flow solvers because the shock wave-boundary layer interaction is strong and the effects ofviscosity are dominant in determining the flow deviation and hence the pressure ratio. Eleven ’blind’solutions were submitted and in addition a ’non-blind’ solution was used to prepare for the exercise-This paper reviews the fiow in the test case and the comparisons of the CFd solutions with the testdata. Lessons for both the Flow Physics in transonic has and for the application of CFd to suchmachines are pointed out.

关键词： transonic compressor rotor shock wave-boundary layer interation CFd ‘blind’ solutions

Solution for fractional potential KdV and Benjamin equations using the novel technique

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Journal of Ocean Engineering and Science 2021年第3期6卷 265-275页

作者： P.Veeresha d.G.Prakasha N.Magesh A.John Christopher deepak Umrao Sarwe department of Mathematics CHRIST(Deemed to be University)Bengaluru-560029India department of Mathematics Faculty of ScienceDavangere UniversityShivagangothriDavangere-577007India P.G.and Research department of Mathematics Govt.Arts College for MenKrishnagiri-635001India department of Mathematics University of MumbaiKalinaSantacruz EastMumbai-400098India

In this paper,we find the solutions for fractional potential Korteweg-de Vries(p-KdV)and Benjamin equations using q-homotopy analysis transform method(q-HATM).The considered method is the mixture of q-homotopy analysis method and Laplace transform,and the Caputo fractional operator is considered in the present *** projected solution procedure manipulates and controls the obtained results in a large admissible ***,it offers a simple algorithm to adjust the convergence province of the obtained *** validate the q-HATM is accurate and reliable,the numerical simulations have been conducted for both equations and the outcomes are revealed through the plots and *** between the obtained solutions with the exact solutions exhibits that,the considered method is efficient and effective in solving nonlinear problems associated with science and technology.

关键词： Potential KdV equation q-Homotopy analysis method Fractional Benjamin equation Laplace transform Ginzburg-Landau equation Caputo fractional operator

Investigation on 1.07 μm laser emission in Nd^(3+)-doped sodium fluoroborate glasses

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Journal of Rare Earths 2012年第5期30卷 413-417页

作者： d.Umamaheswari B.C.Jamalaiah T.Sasikala G.V.Lokeswara Reddy L.Rama Moorthy department of Physics Sri Venkateswara UniversityTirupati517 502India department of Physics Changwon National UniversityChangwon641 773Republic of Korea

Spectroscopic and fluorescence properties of Nd 3＋ ions in sodium fluoroborate（SFB） glasses were prepared and characterized through optical absorption,emission and decay *** energy level analysis was carried out using free-ion Hamiltonian *** oscillator strengths were determined by measuring the area encompassed by the absorption peaks recorded for 1.0 mol.% Nd 3＋-doped *** Judd-Ofelt parameters（2,4,6） were used to evaluate the laser characteristic parameters such as radiative transition probability（A R）,radiative decay time（τ R）,fluorescence branching ratio（β R） and stimulated emission cross-section（σ e） for the 4 F 3/2 metastable *** fluorescence spectra for different concentrations of Nd 3＋ ions were recorded by exciting the samples at 514.5 nm Ar ＋ ion laser.

关键词： sodium fluoroborate glasses rare earth spectroscopy Judd-Ofelt theory laser materials

Primary crystallization process of rapidly solidified Al-Ni-Cu-Nd metallic glasses under continuous heating regime

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中国有色金属学会会刊：英文版 2003年第4期13卷 764-768页

作者：肖于德黎文献 d.Jacovkis N.Clavaguera M.T.Clavaguera-Mora J.Rodriguez-Viejo School of Materials science and Engineering Grup de Fisica de Materials I Fisica de l'Estat Solid

Rapidly solidified Al 87 Ni 7Cu 3Nd 3 metallic glasses were prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter. The metallic glasses were partially crystallized under continuous heating regime. Primary crystallization was studied through structural characterization of the amorphous and partially crystallized ribbons by means of conventional X ray diffraction and transmission electron microscopy with selected area electron diffraction. The results show that, the as spun ribbons are fully amorphous and homogeneous on the micron scale, but contain high density of nanoscale quenched in clusters or crystallite embryos. Primary crystallization mainly leads to formation of two phase mixture of α Al nanocrystalline and residual amorphous phase. Precipitation of α Al nanoparticles is limited by build up and overlapped diffusion field of solute atoms with low diffusion rate. At the earlier stage of primary crystallization the crystal nuclei exhibit high density and growth rate. With the α Al crystal growing, the crystal growth rate decreases, and even at the later stage further crystallization into α Al crystal becomes difficult to occur due to thermal stabilization of the residual nickel and neodymium enriched amorphous phase, the saturated values of crystallized volume fraction and α Al crystal diameter getting to 20%30% and 515 nm.

关键词：铝合金快速凝固连续加热制度结晶过程金属玻璃