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Journal of rare Earths 2018年第4期36卷 390-397页

作者： S.r.Bhongale H.r.Ingawale t.J.Shinde P.N.Vasambekar Department of Physics Yashavantrao Chavan Institute of Science Department of Physics B.V.M.B.S.K.Kanya Mahvidyalaya Department of Physics K.R.P.Kanya Mahvidyalaya Department of Electronics Shivaji University

Nd3＋ substituted spinel ferrites with formula MgxCd1-xNd0.03Fe1.97O4（x = 0.0.2,0.4,0.***.0.8 and 1.0）were prepared by oxalate co-precipitation method using novel microwave sintering technique. Ar grade sulphates were used as starting chemicals. the samples were sintered at optimized power of 70 W for10 min in a microwave oven（800 W）. the structural analysis of these samples was done by using X-ray diffraction, scanning electron microscope and Fourier transform Ir techniques. the XrD analysis of the synthesized ferrite confirms the formation of cubic spinel structure of ferrite. the influence of Nd3＋substitution on various structural parameters of Mg-Cd ferrites was reported. Ir study indicates the spectra contain two intense absorption bands around 600 and 400 cm^（-1） in addition with four extra bands. the magnetic properties of all ferrites were studied by using a vibration sample *** crystallite and grain size dependant magnetic properties are observed. the composition Mg_（0.6）Cd_（0.4）Nd_（0.03）Fe_（1.97）O_4 has better magnetic properties that can be used in recording media. the fast synthesis of spinel ferrites is yielded due to use of the microwave sintering technique.

关键词： Mg-Nd-Cd ferrite rare earth Microwave sintering Ir study Coercive force

Large intestinal dynamics differ between fowl and swine:Anatomical modifications,microbial collaboration,and digestive advantages from fibrolytic enzymes

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Animal Nutrition 2022年第4期11卷 160-170页

作者： Edwin t.Moran Jr. Michael r.Bedford Poultry Science Department Auburn UniversityAL 36830-5416USA AB Vista Woodstock CourtBlenheim RoadMarlboroughWiltshire SN84ANUK

the large intestinal systems of fowl and swine recover nutrients from ileal indigesta by a strategically different *** with fowl enter a short colon where retro-peristalsis using urine from the urodeum carries small particulates and solutes into both ceca while coarse materials collect in the *** repetitively add fine and soluble materials into both ceca to continue fermentation until complexity of the remainder exceeds microbial action,then contents apart from faeces are entirely *** with swine initially enter a short cecum followed by a lengthy progression through to the rectal *** out-pocketings of circular muscle or haustrae occur throughout the length of the pig's cecum and helicoidal *** pocket carries contents acquired earlier in the *** collects fines and solutes into haustrae during their progression through the colon whereas coarse particulates assemble in the *** contents continually ferment during movement to the distal colon with resulting volatile fatty acids(VFA)and electrolytes being *** loosely covers the lumen surface in caeca as well as helicoidal colon that may capture microbes from active intestinal contents as well as release others to sustain *** microbial community continually modifies to accommodate fibre complexity as *** starches(rS)and simple oligosaccharides rapidly ferment to yield VFA while encouraging butyric acid in the cecum and anterior colon,whereas non-starch polysaccharides(NSP)complexity requires extended durations through the remaining colon that enhance acetic *** fibre eventually results in undue complexity for fermentation and consolidates at termination of the *** compact pellets are placed on core contents to form faeces having a nodular ***,propionic,and butyric acids represent the bulk of VFA and are derived from non-digestible *** enzymes,when supplemented

关键词： Butyric acid Endogenous protein Intestinal microbes Large intestine Volatile fatty acids Xylanase

COVID-19: Analytics of contagion on inhomogeneous random social networks

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Infectious Disease Modelling 2021年第1期6卷 75-90页

作者： t.r.Hurd Mathematics&Statistics McMaster University1280 Main St.WestHamiltonOntarioL8S 4L8Canada

Motivated by the need for robust models of the Covid-19 epidemic that adequately reflect the extreme heterogeneity of humans and society,this paper presents a novel framework that treats a population of N individuals as an inhomogeneous random social network(IrSN).the nodes of the network represent individuals of different types and the edges represent significant social *** epidemic is pictured as a contagion process that develops day by day,triggered by a seed infection introduced into the population on day ***’social behaviour and health status are assumed to vary randomly within each type,with probability distributions that vary with their type.A formulation and analysis is given for a SEIr(susceptible-exposed-infective-removed)network contagion model,considered as an agent based model,which focusses on the number of people of each type in each compartment each *** main result is an analytical formula valid in the large N limit for the stochastic state of the system on day t in terms of the initial *** formula involves only one-dimensional *** model can be implemented numerically for any number of types by a deterministic algorithm that efficiently incorporates the discrete Fourier *** the paper focusses on fundamental properties rather than far ranging applications,a concluding discussion addresses a number of domains,notably public awareness,infectious disease research and public health policy,where the IrSN framework may provide unique insights.

关键词： Social network Infectious disease model Complex systems Agent based model Cascade model Poisson random graphs

Is Being Funny a Useful Policy?How Local Governments' Humorous Crisis response Strategies and Crisis responsibilities Influence trust,Emotions,and Behavioral Intentions

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International Journal of Disaster risk Science 2022年第5期13卷 676-690页

作者： Janna Hämpke Stefan röseler Meinald t.thielsch Department of Psychology University of Münster48149 MünsterGermany

this study is the first to investigate how a local government’s humorously framed response strategy on social media to a low-severity crisis influences people ’s trust in the local government and their crisis-related behavioral intentions,specific ally when considering the government’s responsibility for the *** on the situational crisis communication theory,we examined the mediating role of experienced positive or negative affect on people’ s responses to a local government’s crisis communication ***,we exploratorily examined the predictive power and moderating role of demographics,sense of humor,disposition to trust,and the respective crisis scenarios.A total of517 people participated in an online experiment in which they were confronted with three randomly presented fictive crisis scenarios where the local government’s crisis responsibility(high versus low) and the framing of their crisis response strategy(in form of humorous versus rational twitter posts) were systematically varied between ***,the results mostly corroborate earlier findings about the degree of crisis responsibility(that is,when a government’s crisis responsibility is high,people have less trust and behavioral intentions) and about the mediating role of experienced ***,we found that humorously framed strategies negatively influence trust and positive affect(but not behavioral intentions).In contrast to earlier findings,the crisis responsibility × framing interaction was not ***,the results advise against using humor in crisis communications on social media,even in lowseverity *** analyses indicate that further investigations should focus on specific crisis characteristics and potential moderators.

关键词： Afect Crisis communication Crisis responsibility Humor Situational crisis communication theory Social media

torsional wave frequency in heterogeneous earth crust lying over dry sandy semi-infinite substratum

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Applied Mathematics and Mechanics(English Edition) 2019年第10期40卷 1399-1412页

作者： S.K.VISHWAKArMA r.KAUr t.r.PANIGrAHI Department of Mathematics Birla Institute of Technology and SciencePilani Hyderabad Campus

the present study is carried out to investigate the transference of torsional surface waves in a heterogeneous anisotropic crust lying over a dry sandy half-space. the rigidities and densities as well as the initial stress are assumed varying as a function of depth in both the media. these variations are the product of the polynomial function of depth in degree n (n ∈ r) and the exponential function of depth. Following the theory of elastic waves, the mathematical model is established. Separation of variables is used to obtain the displacement in the layer and the half-space. Intrinsic boundary conditions are imposed to derive the dispersion equation. the inhomogeneity parameters associated with the rigidity, the density, and the initial stress of the medium are found to have substantial influence on the phase velocity of the torsional surface wave. the graphical presentations are drawn to exhibit the findings. the results thus obtained are significant for the investigation and characterization of torsional surface wave in the heterogeneous anisotropic layer.

关键词： hypergeometric function Laguerre function torsional wave inhomogeneity gravity initial stress sandy medium

Effects of primary phase morphology on mechanical properties of Al-Si-Mg-Fe alloy in semi-solid slurry casting process

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中国有色金属学会会刊：英文版 2010年第S3期20卷 857-861页

作者： r.BUrAPA S.JANUDOM t.CHUCHEEP r.CANYOOK J.WANNASIN Department of Industrial Engineering Faculty of EngineeringRajamangala University of Technology Srivijaya Department of Mining and Materials Engineering Faculty of EngineeringPrince of Songkla University

the gas induced semi-solid(GISS) process was developed to create semi-solid slurry with fine and uniform globular *** combination of local rapid heat extraction and vigorous agitation by the injection of fine inert gas bubbles through a graphite diffuser in molten metal held at a temperature above its liquidus temperature changes the morphology of primary α(Al) from coarse dendritic to rosette-like and finally to fine *** GISS process produced semi-solid slurry at low solid fractions and then formed the slurry by a squeeze casting process to produce casting *** effects of primary phase morphology on the mechanical properties of Al-Si-Mg-Fe alloy were *** results show that the ultimate tensile strength and elongation are affected by the shape factor and particle size of the primary α(Al).

关键词： gas induced semi-solid(GISS) microstructure mechanical properties semi-solid slurry casting rheocasting

Optimal placement of wind turbines within a wind farm considering multi-directional wind speed using two-stage genetic algorithm

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Frontiers in Energy 2021年第1期15卷 240-255页

作者： A.S.O.OGUNJUYIGBE t.r.AYODELE O.D.BAMGBOJE Power Energy Machines and Drives(PEMD)research Group Department of Electrical and Electronic EngineeringUniversity of IbadanNigeria

Most wind turbines within wind farms are set up to face a pre-determined wind ***,wind directions are intermittent in nature,leading to less electricity production *** paper proposes an algorithm to solve the wind farm layout optimization problem considering multi-angular(MA)wind direction with the aim of maximizing the total power generated on wind farms and minimizing the cost of installation.A twostage genetic algorithm(GA)equipped with complementary sampling and uniform crossover is used to evolve a MA layout that will yield optimal output regardless of the wind *** the first stage,the optimal wind turbine layouts for 8 different major wind directions were determined while the second stage allows each of the previously determined layouts to compete and inter-breed so as to evolve an optimal MA wind farm *** proposed MA wind farm layout is thereafter compared to other layouts whose turbines have focused site specific wind turbine *** results reveal that the proposed wind farm layout improves wind power production capacity with minimum cost of installation compared to the layouts with site specific wind turbine *** paper will find application at the planning stage of wind farm.

关键词： optimal placement wind turbines wind direction genetic algorithm wake effect

Single-source Switched-capacitor Boost Nine-level Inverter with reduced Components

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1688-1697页

作者： Kaibalya Prasad Panda r.t.Naayagi Pravat Kumar ray Gayadhar Panda the Department of Electrical Engineering Pandit Deendayal Energy UniversityGandhinagar 382007India the School of Electrical and Electronic Engineering Newcastle University International Singapore567739Singapore the Department of Electrical Engineering National Institute of Technology RourkelaRourkela 769008India the Department of Electrical Engineering National Institute of Technology MeghalayaShillong 793003India

Increasing demands for improvement in power quality and power capacity have contributed to development of switched-capacitor multilevel inverters(SCMLIs).recently developed SCMLIs enable single-stage voltage boosting,as well as inversion resulting in step-up ac *** reduction in number of components,this paper introduces a boost type singlesource nine-level(9-level)SCMLI employing two capacitors and three *** to the series-parallel connection process,capacitor voltages are inherently balanced and assist in quadruple voltage boosting from a *** voltage stress across semiconductor devices is limited to twice input voltage *** a minimum number of components,the proposed SCMLI can be extended to increase voltage levels without additional dc *** extension module adds two additional voltage steps in the output while maintaining maximum voltage stress the same as 9-level *** by in-depth analysis of circuit operation and power losses,a thorough comparison of recently developed single-phase 9-level MLIs is carried out,which verifies design *** simulation and experimental results are presented to verify the prominent features of the 9-level SCMLI under dynamic operating conditions.

关键词： Multilevel inverter reduced components,self-voltage balance single-source switched-capacitor voltage gain

remarkably high fracture toughness of HfNbtatiZr refractory high-entropy alloy

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Journal of Materials Science & technology 2022年第28期123卷 70-77页

作者： X.J.Fan r.t.Qu Z.F.Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nano Science and technology Institute University of Science and Technology of ChinaSuzhou 215132China

High-entropy alloys(HEAs)with face-centered cubic(FCC)phase such as CoCrFeMnNi or CoCrNi generally exhibit ultra-high fracture toughness but relatively low *** contrast,body-centered cubic(BCC)HEAs often display higher strengths,but the few reports on fracture toughness measurement demonstrate low toughness *** we show that the BCC HfNbtatiZr refractory HEA,which possesses a combination of high strength,good tensile ductility and excellent high-temperature properties,also exhibits a remarkably high fracture *** using the"single specimen"compliance method for J-integral measurement according to the AStM E1820–17 standard,its fracture toughness K_(JIC)was experimentally determined to be 210 MPa m^(1/2),which renders this HEA among the toughest metallic *** excellent damage tolerance makes the HEA promising for applications as high-temperature structural materials such as in aerospace field.

关键词： High-entropy alloys BCC structure Fracture toughness J-integral

Diverse acoustic wave propagation to confirmable time–space fractional KP equation arising in dusty plasma

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Communications in theoretical Physics 2021年第11期73卷 47-64页

作者： Aly r Seadawy Muhammad Younis Muhammad Z Baber Syed t r rizvi Muhammad S Iqbal Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-MunawarahSaudi Arabia Department of Computer Science University of the PunjabLahorePakistan Department of Mathematics and Statistics The University of LahoreLahorePakistan Department of Mathematics COMSATS University IslamabadLahore CampusPakistan

In this study,the(3+1)-dimensional fractional time–space Kadomtsev–Petviashivili(FtSKP)equation is considered and analyzed analytically,which propagates the acoustic waves in an unmagnetized dusty *** fractional derivatives are studied in a confirmable *** new modified extended direct algebraic(MEDA)approach is adopted to investigate the diverse nonlinear wave structures.A variety of new families of hyperbolic and trigonometric solutions are obtained in single and different *** obtained results are also constructed graphically with the different parametric choices.

关键词： exact solutions fractional calculus new MEDA technique unmagnetized dusty plasma