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Magnetic properties and magnetocaloric effects in(Ho_(1-x)Y_x)_5Pd_2 compounds

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Chinese Physics B 2019年第5期28卷 293-299页

作者： X F Wu C P Guo G Cheng C R Li j Wang Y S Du G H Rao Z M Du School of Materials Science and Engineering University of Science and Technology Beijing School of Materials Science and Engineering Guilin University of Electronic Technology Guangxi Key Laboratory of Information Materials

The crystal structure, magnetic and magnetocaloric properties of(Ho_(1-x) Y_(0.5))_5 Pd_2 compounds are investigated. All the compounds crystallize in a cubic Dy_5 Pd_2-type structure with the space group Fd3 m and undergo a second order transition from spin glass(SG) state to paramagnetic(PM) state. The spin glass transition temperatures T_g decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures(θp) for Ho_5 Pd_2,(Ho_(0.75) Y_(0.25)_5 Pd_2, and(Ho_(0.5) Y_(0.5))_5 Pd_2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments(μeff) are10.8 μB/Ho, 10.3 μB/RE, and 7.5 μB/RE, respectively. Magnetocaloric effect(MCE) is anticipated according to the maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change-?SMof the(Ho_(1-x)Y_x)_5 Pd_2(x = 0, 0.25, and 0.5) compounds are determined to be 11.5 j·kg^(-1)·K^(-1), 11.1 j·kg^(-1)·K^(-1), and 8.9 K j·kg^(-1)·K^(-1), with corresponding refrigerant capacity values of 382.3 j·kg^(-1), 336.2 j·kg^(-1), and 242.5 j·kg^(-1), respectively.

关键词： (Ho1-xYx)5Pd2 compounds magnetic transition magnetocaloric effect

Enhanced Constitutive Theories for Classical Thermoviscoelastic Polymeric Fluids

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Applied Mathematics 2022年第11期13卷 917-947页

作者： Karan S. Surana Thomas j. Ezell Department of Mechanical Engineering University of Kansas Lawrence KS USA

This paper presents ordered rate nonlinear constitutive theories for thermoviscoelastic fluids based on Classical Continuum Mechanics (CCM). We refer to these fluids as classical thermoviscoelastic polymeric fluids. The conservation and balance laws of CCM constitute the core of the mathematical model. Constitutive theories for the Cauchy stress tensor are derived using the conjugate pair in the entropy inequality, additional desired physics, and the representation theorem. The constitutive theories for the Cauchy stress tensor consider convected time derivatives of Green’s strain tensor or the Almansi strain tensor up to order n and the convected time derivatives of the Cauchy stress tensor up to order m. The resulting constitutive theories of order (m, n) are based on integrity and are valid for dilute as well as dense polymeric, compressible, and incompressible fluids with variable material coefficients. It is shown that maxwell, Oldroyd-B, and Giesekus constitutive models can be described by a single constitutive theory. It is well established that the currently used maxwell and Oldroyd-B models predict zero normal stress perpendicular to the flow direction. It is shown that this deficiency is a consequence of not retaining certain generators and invariants from the integrity (complete basis) in the constitutive theory and can be corrected by including additional generators and invariants in the constitutive theory. Similar improvements are also suggested for the Giesekus constitutive model. Model problem studies are presented for BVPs consisting of fully developed flow between parallel plates and lid-driven cavities utilizing the new constitutive theories for maxwell, Oldroyd-B, and Giesekus fluids. Results are compared with those obtained from using currently used constitutive theories for the three polymeric fluids.

关键词： Polymeric Fluids maxwell Oldroyd-B Giesekus Mathematical Models Nonlinear Rate Constitutive Theories Representation Theorem Integrity Generators Invariants

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检查前用药可降低乳腺钼钯X线检查中的不适

国际医学放射学杂志 2008年第A6期31卷 483-483页

作者： C.K.Lambertz C.j.johnson P.G.Montgomery j.R.maxwell 林满霞 St Luke’s Mountain States Tumor Institute

目的验证乳腺钼钯X线检查前给予对乙酰氨基酚、布洛酚和(或)4%利多卡因凝胶能否减轻检查不适或提高普查中有恐惧感妇女的满意度。

关键词：乳腺钼钯 X线检查多卡因乙酰氨基酚布洛意度学术审查知情同意书感觉不适视觉模拟

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心脏穿刺伤的实用处理

南京医科大学学报(自然科学版) 1957年第1期 72-72页

作者： j.maxwell Chamberlain David M.Carberry Paul L.Stefko 王一镗

心脏穿刺伤的处理要求我们具有心呼吸生理的现代知识。以往教科书武断地认为心脏穿刺伤的致死原因是心脏填塞(Cardiac Tamponade),故不用静脉输液或输血,以免再增加静脉压力。而且,主要只注意右心及循环郁积,甚至连休克的存在也忽略了... 详细信息

心脏穿刺伤的处理要求我们具有心呼吸生理的现代知识。以往教科书武断地认为心脏穿刺伤的致死原因是心脏填塞(Cardiac Tamponade),故不用静脉输液或输血,以免再增加静脉压力。而且,主要只注意右心及循环郁积,甚至连休克的存在也忽略了。现在的紧急治疗乃注意支持左心及体循环。由于现代心脏的外科进展,处理心脏的损伤,积累了不少经验,目前考虑致死的主要因素为:(1)

关键词：心包内血液解剖学呼吸生理胸腔积血出血血胸

Potential factors influencing lymphatic filariasis transmission in"hotspot"and"control"areas in Ghana:the importance of vectors

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Infectious Diseases of Poverty 2019年第1期8卷 45-55页

作者： Sellase Pi-Bansa joseph Harold Nyarko Osei Kwadwo Kyeremeh Frempong Elizabeth Elhassan Osei Kweku Akuoko David Agyemang Collins Ahorlu maxwell Alexander Appawu Benjamin Guibehi Koudou Michael David Wilson Dziedzom Komi de Souza Samuel Kweku Dadzie jurg Utzinger Daniel Adjei Boakye Swiss Tropical and Public Health Institute BaselSwitzerland University of Basel BaselSwitzerland Noguchi Memorial Institute for Medical Research College of Health SciencesUniversity of GhanaLegonGhana Department of Animal Biology and Conservation Science University of GhanaLegonGhana SightSavers International Ghana OfficeAccraGhana African Regional Postgraduate Programme in Insect Science University of GhanaLegonGhana Vector Biology Department Liverpool School of Tropical MedicineLiverpoolUK Centre Suisse de Recherches Scientifiques en Cote d'Ivoire AbidjanCote d'Ivoire

Background:Mass drug administration(MDA)programmes for the control of lymphatic filariasis in Ghana,have been ongoing in some endemic districts for 16 *** current study aimed to assess factors that govern the success of MDA programmes for breaking transmission of lymphatic filariasis in ***:The study was undertaken in two"hotspot"districts(Ahanta West and Kassena Nankana West)and two control districts(Mpohor and Bongo)in *** were collected and identified using morphological and molecular tools.A proportion of the cibarial armatures of each species was *** were performed onAnopheles gambiae for filarial worm detection.A questionnaire was administered to obtain information on MDA compliance and vector control *** were compared between districts to determine factors that might explain persistent transmission of lymphatic ***:High numbers of mosquitoes were sampled in Ahanta West district compared to Mpohor district(F=16.09,P=0.002).There was no significant difference between the numbers of mosquitoes collected in Kassena Nankana West and Bongo districts(F=2.16,P=0.185).Mansonia species were predominant in Ahanta West *** mosquitoes were prevalent in all *** with infected and infective filarial worms was found only in Ahanta West *** differences were found in cibarial teeth numbers and shape for mosquito species in the surveyed *** MDA coverage was high in all *** average use of bednet and indoor residual spraying was 82.4 and 66.2%,*** was high compliance in the five preceding MDA rounds in Ahanta West and Kassena Nankana West districts,both considered hotspots of lymphatic filariasis ***:The study on persistent transmission of lymphatic filariasis in the two areas in Ghana present information that shows the importance of local understanding of factors affecting control and elimination of lymphatic

关键词： Ghana Hotspots Lymphatic filariasis Mass drug administration Microfilariae Systematic non-compliance Vector control

Electromagnetophoresis of a Colloidal Sphere in a Spherical Cavity

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journal of Electromagnetic Analysis and Applications 2014年第10期6卷 269-279页

作者： Tzu H. Hsieh Huan j. Keh Department of Chemical Engineering National Taiwan University Taipei Taiwan

The quasi-steady electromagnetophoretic motion of a spherical colloidal particle positioned at the center of a spherical cavity filled with a conducting fluid is analyzed at low Reynolds number. Under uniformly applied electric and magnetic fields, the electric current and magnetic flux density distributions are solved for the particle and fluid phases of arbitrary electric conductivities and magnetic permeabilities. Applying a generalized reciprocal theorem to the Stokes equations modified with the resulted Lorentz force density and considering the contribution of the magnetic maxwell stress to the force exerted on the particle, which turns out to be important, we obtain a closed-form formula for the migration velocity of the particle valid for an arbitrary value of the particle-to-cavity radius ratio. The particle velocity in general decreases monotonically with an increase in this radius ratio, with an exception for the case of a particle with high electric conductivity and low magnetic permeability relative to the suspending fluid. The asymptotic behaviors of the boundary effect on the electromagnetophoretic force and mobility of the confined particle at small and large radius ratios are discussed.

关键词： Electromagnetophoresis Magnetohydrodynamics Lorentz Force Colloid

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纤维物质对母猪繁殖性能的作用

中国动物保健 1999年第10期1卷 30-30页

作者： K.S.Sohn C.V.maxwell 张浩安徽省农科院畜牧兽医研究所

仔猪断奶前死亡率为13%～25%,其中60%是在出生后3～4天内死亡的(Pomemy1960;England,1986;USDA,1992)通过调控母猪日粮来增加新生仔猪体能贮存可以提高其成活率。许多学者发现在妊娠母猪日粮中添加1.3-j二醇(Stahly,1980,1982;Rosebrou... 详细信息

仔猪断奶前死亡率为13%～25%,其中60%是在出生后3～4天内死亡的(Pomemy1960;England,1986;USDA,1992)通过调控母猪日粮来增加新生仔猪体能贮存可以提高其成活率。许多学者发现在妊娠母猪日粮中添加1.3-j二醇(Stahly,1980,1982;Rosebrough 等,1981)中等链长甘油酯(New-comb 等1991;Azain,1993)或有机酸(Spence,1985)可提高母体血液中的生酮代谢物,节约葡萄糖,为胎儿生长和贮存体能提供更多的可利用物质。生酮物质的非氧化作用。

关键词：母猪繁殖性能妊娠母猪胎儿生长断奶前死亡率新生仔猪日粮纤维水平妊娠期碳水化合物生酮物质可利用

Self-consistent maxwell–Bloch model for highorder harmonic generation in nanostructured semiconductors

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Photonics Research 2022年第9期10卷 2099-2106页

作者： ANTON RUDENKO MARIA K.HAGEN jÖRG HADER STEPHAN W.KOCH jEROME V.MOLONEY Arizona Center for Mathematical Sciences and Wyant College of Optical Sciences University of ArizonaTucsonArizona 85721USA Department of Physics and Material Sciences Center Philipps-Universität MarburgMarburg 35032Germany

In pursuit of efficient high-order harmonic conversion in semiconductor devices,modeling insights into the complex interplay among ultrafast microscopic electron–hole dynamics,nonlinear pulse propagation,and field confinement in nanostructured materials are urgently ***,a self-consistent approach coupling semiconductor Bloch and maxwell equations is applied to compute transmission and reflection high-order harmonic spectra for finite slab and sub-wavelength nanoparticle *** increase in the generated high harmonics by several orders of magnitude is predicted for gallium arsenide nanoparticles with a size maximizing the magnetic dipole *** as a conceptual and predictive tool for ultrafast spatiotemporal nonlinear optical responses of nanostructures with arbitrary geometry,our approach is anticipated to deliver new strategies for optimal harmonic manipulation in semiconductor metadevices.

关键词： harmonic Bloch maxwell

A New Formulation of maxwell’s Equations in Clifford Algebra

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journal of Applied Mathematics and Physics 2017年第8期5卷 1575-1588页

作者： Pirooz Mohazzabi Norbert j. Wielenberg Gary Clark Alexander Department of Mathematics and Physics University of Wisconsin-Parkside Kenosha WI USA Department of Mathematical Sciences DePaul University Chicago IL USA

A new unification of the maxwell equations is given in the domain of Clifford algebras with in a fashion similar to those obtained with Pauli and Dirac algebras. It is shown that the new electromagnetic field multivector can be obtained from a potential function that is closely related to the scalar and the vector potentials of classical electromagnetics. Additionally it is shown that the gauge transformations of the new multivector and its potential function and the Lagrangian density of the electromagnetic field are in agreement with the transformation rules of the second-rank antisymmetric electromagnetic field tensor, in contrast to the results obtained by applying other versions of Clifford algebras.

关键词： Clifford Algebra maxwell’s Equations Electromagnetism Vector Potential