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The Lambert-G Family:Properties,inference,and Applications

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Computer Modeling in Engineering & sciences 2024年第7期140卷 513-536页

作者： Jamal n.Al Abbasi Ahmed Z.Afify Badr Alnssyan Mustafa s.shama Accounting Department Ashur UniversityBaghdad10011Iraq Department of statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt Department of Management information systems and Production Management College of Business and EconomicsQassim UniversityBuraydah51452Saudi Arabia Department of Basic sciences Common First Year(CFY)King Saud UniversityRiyadh11362Saudi Arabia Department of Mathematics and statistics Osim Higher Institute of Administrative ScienceOsim12961Egypt

This study proposes a new flexible family of distributions called the Lambert-G *** Lambert family is very flexible and exhibits desirable *** three-parameter special sub-models provide all significantmonotonic and non-monotonic failure rates.A special sub-model of the Lambert family called the Lambert-Lomax(LL)distribution is *** expressions for the LL statistical properties are *** of the LL distribution are addressed mathematically based on its hazard *** estimation of the LL parameters is discussed using six estimation *** performance of this estimation method is explored through simulation *** usefulness and flexibility of the LL distribution are demonstrated empirically using two real-life data *** LL model better fits the exponentiated Lomax,inverse power Lomax,Lomax-Rayleigh,power Lomax,and Lomax distributions.

关键词： Lambert function Lomax distribution maximum likelihood hazard function statistical model simulation

不同振荡热压烧结温度下90W-10Cu难熔合金组织及性能

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工程科学与技术 2024年第3期56卷 269-276页

作者：高卡赵桅孙德建高阳朱文博上海理工大学机械工程学院上海200093 长海医院全科医学科上海200433 郑州航空工业管理学院材料学院河南郑州450015

用于高压电触头材料的90W-10Cu难熔合金由于具有高熔点和高比重差异,在高温长时间的粉末冶金过程中存在致密化困难和晶粒异常长大而影响其性能。在常规热压烧结基础上,振荡热压烧结(HOP)技术采用一定频率的循环振荡单轴压力代替静单轴压... 详细信息

用于高压电触头材料的90W-10Cu难熔合金由于具有高熔点和高比重差异,在高温长时间的粉末冶金过程中存在致密化困难和晶粒异常长大而影响其性能。在常规热压烧结基础上,振荡热压烧结(HOP)技术采用一定频率的循环振荡单轴压力代替静单轴压力,可快速促进陶瓷等材料的致密化。因此,为了研究振荡热压烧结对90W-10Cu难熔合金的低温烧结效果,本文将振荡热压烧结技术应用到90W-10Cu(质量分数)难熔合金的制备中,研究了烧结温度(1000~1300℃)对其微观组织、致密度、晶粒尺寸、硬度及电导率性能的影响。研究结果发现,振荡热压烧结90W-10Cu合金由W相基体和Cu相黏结相组成。随着烧结温度的升高,90W-10Cu难熔合金的致密度逐渐增大,在烧结温度最高为1300℃时,其致密度最高可达到99.35%,均高于同等温度下的热压烧结样品的致密度;而晶粒尺寸仅为4.97μm左右,没有异常长大,达到了细化晶粒的效果;同时,其W晶粒邻接度逐渐降低,合金的微观组织均匀性得到优化和改善;维氏硬度和电导率分别达到225.78 HV_(30)和27.88%国际退火铜标准(iACs),高于同等温度甚至高100℃时的热压烧结体,性能得到显著提升,达到了低温烧结效果。结果表明,振荡热压烧结能够有效地促进90W-10Cu难熔合金的致密化,降低烧结温度和抑制晶粒生长,显著优化其微观组织均匀性,有利于在较低温度下获得高致密度、晶粒细小、高硬度和高电导率的90W-10Cu难熔合金材料。

关键词：烧结难熔合金致密化晶粒尺寸及形貌硬度电导率

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed sintering and Post Treatment

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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue s.Y.Peng X.Zhang C.n.He Y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China school of Materials science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%iACs and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability strength Electrical conductivity

Ca-based materials derived from calcined cigarette butts for CO_(2)capture and thermochemical energy storage

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Journal of Environmental sciences 2024年第6期140卷 230-241页

作者： nabil Amghar Virginia Moreno Pedro E.sánchez-Jiménez Antonio Perejón Luis A.Pérez-Maqueda instituto de Ciencia de Materiales de sevilla C.S.I.C.-Universidad de SevillaC.Américo Vespucio4941092 SevillaSpain instituto de Tecnología de Materiales(iTM) Universitat Politècnica de València(UPV)Plaza Ferrándiz y Carbonell 1AlcoyAlicante 03801Spain Departamento de Química inorgánica Facultad de QuímicaUniversidad de Sevilla41012 SevillaSpain

Cigarette butts(CBs)are one of the most common types of litter in the *** to the toxic substances they contain,the waste generated poses a harmful risk to the environment,and therefore there is an urgent need for alternative solutions to landfill ***,this work presents a possible revalorization of this waste material,which implies interesting environmental *** were used as sacrificial templates for the preparation of CaO-based materials by impregnation with calcium and magnesium nitrates followed by flaming *** materials presented enhanced porosity for their use in the Calcium Looping process applied either to thermochemical energy storage or CO_(2)capture *** influence of the concentration of Ca and Mg in the impregnating solutions on the multicycle reactivity of the samples was *** improved multicycle performance was obtained in terms of conversion for both applications.

关键词： Cigarette butts Calcium-Looping CO_(2)Capture Thermochemical energy storage

First 150 years of catatonia:Looking back at its complicated history and forward to the road ahead

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World Journal of Psychiatry 2024年第5期14卷 600-606页

作者： Levente Csihi Gabor s Ungvari stanley n Caroff Gábor Gazdag Department of Psychiatry and Psychiatric Rehabilitation Jahn Ferenc South Pest HospitalBudapest 1204Hungary Division of Psychiatry School of MedicineUniversity of Western AustraliaCrawley 6009Western AustraliaAustralia section of Psychiatry University of Notre DameFremantle 6160Western AustraliaAustralia Behavioral Health service Corporal Michael J CresenczVeterans Affairs Medical CenterPhiladelphiaPA 19104United States Department of Psychiatry University of PennsylvaniaPerelman School of MedicinePhiladelphiaPA 19104United States Department of Psychiatry and Psychotherapy Faculty of MedicineSemmelweis UniversityBudapest 1083Hungary

karl Ludwig kahlbaum(1828-1899)was the first to conceptualize and describe the main clinical features of a novel psychiatric illness,which he termed catatonia in his groundbreaking monograph published 150 years *** kahlbaum postulated catatonia as a separate disease entity characterized by psychomotor symptoms and a cyclical course,a close examination of his 26 cases reveals that most of them presented with motor symptom complexes or syndromes associated with various psychiatric and medical *** his classification system,Kraepelin categorized catatonic motor symptoms that occur in combination with psychotic symptoms and typically have a poor prognosis within his dementia praecox(schizophrenia)disease *** of the substantial influence of Kraepelin’s classification,catatonia was predominantly perceived as a component of schizophrenia for most of the 20th ***,with the advent of the psychopharmacotherapy era starting from the early 1950s,interest in catatonia in both clinical practice and research subsided until the early *** past two decades have witnessed a resurgence of interest in *** Diagnostic and statistical Manual of Mental Disorders Fifth Edition,marked a paradigmatic shift by acknowledging that catatonia can occur secondary to various psychiatric and medical *** introduction of an independent diagnostic category termed“Catatonia not Otherwise specified”significantly stimulated research in this *** authors briefly review the history and findings of recent catatonia research and highlight promising directions for future exploration.

关键词： Catatonia Historical overview Psychopharmacology Diagnostic and statistical Manual of Mental Disorders-5 Wernicke-Kleist-Leonhard school

Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical science and Engineering 2022年第3期16卷 433-442页

作者： katarína Gáborová Marcela Achimovičová Michal Hegedüs Vladimír Girman Mária kaňuchová Erika Dutková institute of Geotechnics Slovak Academy of SciencesKošice04001Slovakia institute of Metallurgy Faculty of MaterialsMetallurgy and RecyclingTechnical UniversityKošice04201Slovakia synthon s.r.o.Blansko67801Czech Republic Faculty of science Pavol JozefŠafárik UniversityKošice04154Slovakia institute of Earth Resources Faculty of MiningEcologyProcess Control and GeotechnologiesTechnical UniversityKošice04200Slovakia

Copper(i)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball *** kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/se *** X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)se with the crystallite size∼25 *** surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and se 3d signals corresponded to Cu^(+)and se^(2−)oxidation *** electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as *** optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence *** direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size *** type of Cu_(2)se synthesis can be easily adapted to production dimensions using an industrial vibratory *** advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu_(2)se.

关键词： Cu_(2)se berzelianite nanocrystalline semiconductor mechanochemical synthesis planetary ball mill

ERROR EsTiMATEs FOR THE TiME DisCRETiZATiOn FOR nOnLinEAR MAXWELL's EQUATiOns

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Journal of Computational Mathematics 2008年第5期26卷 677-688页

作者： Mavián slodika Ján Bua Jr. Department of Mathematical Analysis Ghent University

This paper is devoted to the study of a nonlinear evolution eddy current model of the type δtB（H）＋ △↓× （ △↓ × H） =0 subject to homogeneous Dirichlet boundary conditions H × v = 0 and a given initial datum. Here, the magnetic properties of a soft ferromagnet are linked by a nonlinear material law described by B（H）. We apply the backward Euler method for the time discretization and we derive the error estimates in suitable function spaces. The results depend on the nonlinearity of B（H）.

关键词： Electromagnetic field nonlinear eddy current problem Time discretization,Error estimate.

numerical Analysis of the Magnetic Dipole Effect on a Radiative Ferromagnetic Liquid Flowing over a Porous stretched sheet

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Fluid Dynamics & Materials Processing 2024年第2期20卷 293-310页

作者： G.Dharmaiah F.Mebarek-Oudina K.s.Balamurugan n.Vedavathi Department of Mathematics Narasaraopeta Engineering CollegeNarasaraopetIndia Department of Physics Faculty of SciencesUniversity of 20 Août 1955-SkikdaSkikdaAlgeria Department of Mathematics RVR&JC College of EngineeringGunturIndia Department of Mathematics Koneru Lakshmaiah Education FoundationVaddeswaramIndia

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidﬂowing over a stretched surface in the presence of Brownian motion and thermophoresis are *** means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)*** impact of various parameters,namely the velocity,temperature,concentration,is presented *** is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanoﬂuid and,consequently,the heat *** with earlier studies indicates high accuracy and effectiveness of the numerical *** increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary *** skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller nusselt number.

关键词： Brownian motion thermo-phoresis radiation magnetic dipole BVP4C non-linear

Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCs Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry i.nazarov Jorge Labella Alexey V.Kuzmin Maxim A.Faraonov Evgenii n.ivanov salavat s.Khasanov Tomas Torres Mikhail K.islyaikin Dmitri V.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAs 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid institute of solid-state Physics RAs 142432 Chernogolovka Research institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov institute of solution Chemistry of the Russian Academy of sciences 153045 Ivanovo institute for Advanced Research in Chemical sciences Universidad Autonoma de Madrid28049 Madrid iMDEA-nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism