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Semiconductor nanostructures enabled by aerosol technology

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Frontiers of physics 2014年第3期9卷 398-418页

作者： Martin H. Magnusson b. Jonas Ohlsson Mikael t. bjork Kimberly A. Dick Magnus t. borgstrom Knut Deppert Lars Samuelson Solid State Physics Lund University Box 118 SE-22100 Lund Sweden Sol Voltaics Ab Ideon Science Park Scheelevagen 17 SE-22370 Lund Sweden QuNano Ab Ideon Science Park Scheelevaigen 17 SE-22370 Lund Sweden Center for Analysis and Synthesis Lund University Box 124 SE-22100 Lund Sweden

Aerosol technology provides efficient methods for producing nanoparticles with well-controlled composition and size distribution. this review provides an overview of methods and results obtained by using aerosol technology for producing nanostruetures for a variety of applications in semiconductor physics and device technology. Examples are given from： production of metal and metal alloy particles： semiconductor nanoparticles; semiconductor nanowires, grown both in the aerosol phase and on substrates; physics studies based on individual aerosol-generated devices; and large area deviees based on aerosol particles.

关键词： aerosol nanoparticle nanowire metal-organic vapor phase epitaxy (MOVPE) device physics light emitting diodes (LED) solar cell

Determinations of strategy responding to COVID-19

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Economic and Political Studies 2021年第2期9卷 135-147页

作者： Wilson X.b.Li tina t.He Division of business and Management BNU-HKBU United International CollegeZhuhaiChina

this study explores what determines the selection of strategies by governments responding to *** answer the question,we propose concepts of individual utility and societal utility and build a simple *** applying the model,we predict that countries with an individualist culture would adopt more passive strategies while countries with a collectivist culture would adopt more active *** comparison between strategies adopted in China and in the United Kingdom supports the ***,as the spread of COVID-19 virus continues,governments’response may change and individualist countries may switch to more active *** we extend our model to incorporate the dynamics of strategy selection,and explain the switch between passive and active *** then predict in particular that facing the unexpected infections and deaths,the countries with an individualist culture would temporally adopt a relatively more active strategy responding to *** evidence from Spain shows the dynamic feature of strategy selection as predicted by our model.

关键词： Strategy COVID-19 pandemic economic model the United Kingdom China Spain

three-Dimensional Numerical Modeling of an Ar-N_2 Plasma Arc Inside a Non-transferred torch

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Plasma Science and technology 2009年第6期11卷 679-687页

作者： b.SELVAN K.RAMACHANDRAN K.P.SREEKUMAR t.K.tHIYAGARAJAN P.V.ANANtHAPADMANAbHAN School of Mechanical and building Sciences Vellore Institute of Technology UniversityVellore 632014India Laser and Plasma technology Division Bhabha Atomic Research CentreMumbai 400085India

A three-dimensional numerical model is developed to study the behaviour of an argon-nitrogen plasma arc inside a non-transferred torch. In this model, both the entire cathode and anode nozzle are considered to simulate the plasma arc. the argon-nitrogen plasma arc is simulated for different arc currents and gas flow rates of argon. Various combinations of arc core radius and arc length, which correspond to a given torch power, are predicted. A most feasible combination of the same, which corresponds to an actual physical situation of the arc inside the torch, is identified using the thermodynamic principle of minimum entropy production for a particular torch power. the effect of the arc current and gas flow rate on the plasma arc characteristics and torch efficiency is explained. the effect of the nitrogen content in the plasma gas on the torch power and efficiency is clearly detected. Predicted torch efficiencies are comparable to the measured ones and the effect of the arc current and gas flow rate on predicted and measured efficiencies is almost similar. the efficiency of the torch, cathode and anode losses and core temperature and velocity at the nozzle exit are reported for five different cases.

关键词： plasma arc numerical modeling plasma torch minimum entropy production electro-thermal efficiency

Drop formation at nozzles submerged in quiescent continuous phase： an experimental study with tbP-dodecane and nitric acid system

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Nuclear Science and techniques 2018年第6期29卷 110-118页

作者： Amitava Roy MayurDarekar K. K. Singh K. t. Shenoy R. b. Grover Homi bhabha National Institute Anushaktinagar Mumbai 400094 India Chemical Engineering Division Bhabha Atomic Research Centre Mumbai 400085 India

Solvent extraction is an important process in the nuclear fuel cycle. tributyl phosphate(tbP) diluted with dodecane is commonly used as a solvent for extracting heavy metals from nitric acid medium. Studies on hydrodynamics of a single drop, which is the smallest mass transfer entity, are required for better understanding of the complex mass transfer and phase separation phenomena that occur in extraction equipment. In this study, drop formation at nozzles is studied using 30% tbP-dodecane as the dispersed phase and dilute nitric acid as the quiescent continuous phase. Experiments are carried out to determine the drop diameter, jetting velocity, drop detachment height and drop detachment time for various dispersed phase velocities, nozzle diameters(1.91, 3.04, and 4.88 mm), and nitric acid concentrations(0.01, 1, 3 N). Drop formation is captured using high-speed imaging, which enables quantification of drop size, onset of jetting, drop detachment height, and drop detachment time. Experimental data are used to propose correlations for predicting drop diameter and minimum jetting velocity. the correlations are found to be very accurate with average absolute relative errors being 5.23 and 2.97%, respectively.

关键词：试验性硝酸静止沉没系统高速度分离现象磷酸盐

Inhomogeneous dealloying kinetics along grain boundaries during liquid metal dealloying

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Journal of Materials Science & technology 2022年第11期106卷 41-48页

作者： S.-H.Joo Y.b.Jeong t.Wada I.V.Okulov H.Kato Department of Materials Science and Engineering Dankook University119 Dandae-roCheonan 31116Korea Institute for Materials Research Tohoku UniversityKatahira 2-1-1Sendai 980-8577Japan Institute of Natural Sciences and Mathematics Ural Federal University620000 EkaterinburgRussia Faculty of Production Engineering University of BremenBadgasteiner Str.128359 BremenGermany Leibniz Institute for Materials Engineering-IWt Badgasteiner Str.328359 BremenGermany

In this study, the inhomogeneous dealloying phenomenon during the liquid metal dealloying(LMD) was investigated using FeNi+Mg and(FeCo)Ni+Mg systems. For the FeNi+Mg system, the inhomogeneous dealloying and wetting of Mg melt occurred along triple junction(tJ) and grain boundary(Gb).temperature increase enhances the inhomogeneous dealloying kinetics and leads to the formation of the plate-shaped abnormal ligaments at the Gb region. the energy banlance between a Gb energy(γGb)and solid-liquid interface energies(γsl) is the key factor governing the inhomogeneous dealloying and wetting. Particularly, the low-energy twin boundaries were unaffected by the inhomogeneous ***, precursor microstructure is an important factor determining the final morphology of dealloyed material as well as its physical properties. In the case of the(FeCo)Niprecursor, all tJ and Gb were stable against the preferred penetration of Mg melt from 600 ℃ to 800 ℃. It was concluded that a minor addition of alloying elements(VorCr) changes Gb characteristics as well as γslof the precursor ***, this significantly influences dealloying mechanisms and final morphology of the dealloyed material. the current findings demonstrate the importance of Gb engineering in the precursor materials for the technological application of liquid metal dealloying for the synthesis of advanced structural and functional materials.

关键词： Liquid metal dealloying Inhomogeneous dealloying Dealloying mechanism Abnormal ligament Porous material

bulk nanocrystalline W-ti alloys with exceptional mechanical properties and thermal stability

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Journal of Materials Science & technology 2022年第19期114卷 16-28页

作者： H.X.Xue X.C.Cai b.R.Sun X.Shen C.C.Du X.J.Wang t.t.Yang S.W.Xin t.D.Shen Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China CSSC 723rd Research Institute China State Shipbuilding Corporation LimitedYangzhou 225000China

Nanocrystalline(NC)W metals and alloys often exhibit higher radiation tolerance and strength than their coarse-grained ***,their thermal stability is low,making it difficult to achieve bulk NC W metals and alloys by consolidation using conventional techniques such as pressure-less sintering,hot-explosive-compaction sintering,and spark plasma *** we report the synthesis and mechanical properties of bulk NC W_(100-x)ti_(x)(x=10 at.%-30 at.%)alloys prepared by consolidating mechanically alloyed NC powders under a high-temperature/high-pressure *** 20 at.%-30 at.%ti largely improves the sinterability of NC W-ti alloy *** room-temperature microhardness and compressive yield strength of consolidated bulk NC W_(80)ti_(20) alloy are∼16.9 and 6.0 GPa,respectively,which are mainly caused by grain boundary strengthening and significantly higher than those of previously reported W and W *** ultimate compressive strength of bulk NC W_(80)ti_(20) measured between 900 and 1100°C deceases with increasing *** behavior can be explained by the activation of Rachinger grain boundary *** grain growth is observed in bulk NC W_(80)ti_(20) after compression at 1000°*** calculation suggests that it is the segregation of ti at grain boundaries that decreases the specific grain boundary free energy and makes the NC W_(80)ti_(20) alloy thermodynamically stable.

关键词： Nanocrystalline W-ti alloys Segregation Grain boundary energy Strength Hardness

DYNAMICAL ANALYSIS OF A 3-D CHAOtIC SYStEM WItH ONLY tWO QUADRAtIC NONLINEARItIES

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Journal of Systems Science & Complexity 2008年第1期21卷 67-75页

作者： Zeraoulia ELHADJ Department of Mathematics University of TébéssaTebessa 12000Algeria

the paper reports the dynamical study of a three-dimensional quadratic autonomous chaotic system with only two quadratic nonlinearities, which is a special case of the so-called conjugate Lue system. basic properties of this system are analyzed by means of Lyapunov exponent spectrum and bifurcation diagram. the analysis shows that the system has complex dynamics with some interesting characteristics in which there are several periodic regions, but each of them has quite different periodic orbits.

关键词： bifurcation conjugate attractors degeneration Lyapunov exponent quadratic chaotic system.

An Optimized Deep-Learning-based Low Power Approximate Multiplier Design

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Computer Systems Science & Engineering 2023年第2期44卷 1647-1657页

作者： M.Usharani b.Sakthivel S.Gayathri Priya t.Nagalakshmi J.Shirisha Department of Electronics and Communication Engineering Er.Perunal Manimekalai College of EngineeringKonneripalliHosur635117India Department of Electronics and Communication Engineering Pandian Saraswathi Yadav Engineering CollegeSivagangaiTamilnadu630561India Department of Electronics and Communication Engineering R.M.D Engineering CollegeGummidipundiTamilnadu601206India Department of Computer Science and Engineering Koneru Lakshmaiah Education FoundationVaddeswaramGuntur522502India Department of Electronics and Communication Engineering Malla Reddy Engineering CollegeHyderabadTelangana500015India

Approximate computing is a popularﬁeld for low power consumption that is used in several applications like image processing,video processing,multi-media and data *** Approximate computing is majorly performed with an arithmetic circuit particular with a *** multiplier is the most essen-tial element used for approximate computing where the power consumption is majorly based on its *** are several researchers are worked on the approximate multiplier for power reduction for a few decades,but the design of low power approximate multiplier is not so *** seems a bigger challenge for digital industries to design an approximate multiplier with low power and minimum error rate with higher *** overcome these issues,the digital circuits are applied to the Deep Learning(DL)approaches for higher *** recent times,DL is the method that is used for higher learning and prediction accuracy in severalﬁ***,the Long Short-term Memory(LStM)is a popular time series DL method is used in this work for approximate *** provide an optimal solution,the LStM is combined with a meta-heuristics Jel-lyﬁsh search optimisation technique to design an input aware deep learning-based approximate multiplier(DLAM).In this work,the jelly optimised LStM model is used to enhance the error metrics performance of the Approximate *** optimal hyperparameters of the LStM model are identiﬁed by jelly search ***ﬁne-tuning is used to obtain an optimal solution to perform an LStM with higher *** proposed pre-trained LStM model is used to generate approximate design libraries for the different truncation levels as a func-tion of area,delay,power and error *** experimental results on an 8-bit multiplier with an image processing application shows that the proposed approx-imate computing multiplier achieved a superior area and power reduction with very good results on error rates.

关键词： Deep learning approximate multiplier LStM jellyﬁsh

A Cell-based Smoothed Finite Element Method for Modal Analysis of Non-Woven Fabrics

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Computers, Materials & Continua 2021年第6期67卷 2765-2795页

作者： Nguyen t.Quyen N.Dourado A.J.P.Gomes F.b.N.Ferreira C2t—Centro de Ciência e tecnologia têxtil Departamento de Engenharia TêxtilUniversidade do MinhoCampus de AzurémGuimarães4804-533Portugal CMEMS-UMinho Departamento de Engenharia MecânicaUniversidade do MinhoCampus de AzurémGuimarães4804-533Portugal Department of Computer Science Universidade da Beira InteriorConvento de Sto.AntónioCovilhã6201-001Portugal Instituto de telecomunicações R.Marquês deÁvila e BolamaCovilhã6201-001Portugal

the combination of a 4-node quadrilateral mixed interpolation of tensorial components element(MItC4)and the cell-based smoothed finite element method(CSFEM)was formulated and implemented in this work for the analysis of free vibration and unidirectional buckling of shell *** formulation was applied to numerous numerical examples of non-woven *** CSFEM schemes do not require coordinate transformation,spurious modes and numerical instabilities are prevented using bilinear quadrilateral element subdivided into two,three and four smoothing *** improvement of the original CSFEM formulation was made regarding the calculation of outward unit normal vectors,which allowed to remove the integral operator in the strain smoothing *** procedure conducted both to the simplification of the developed formulation and the reduction of computational cost.A wide range of values for the thickness-to-length ratio and edge boundary conditions were *** developed numerical model proved to overcome the shear locking phenomenon with success,revealing both reduced implementation effort and computational cost in comparison to the conventional FEM *** cell-based strain smoothing technique used in this work yields accurate results and generally attains higher convergence rate in energy at low computational cost.

关键词： Mindlin-Reissner theory of plates shear-locking gradient/strain smoothing technique non-woven fabric