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Dynamic recrystallization and Texture Evolution of gW94 Mg Alloy During Multi-and unidirectional Impact Forging

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Acta Metallurgica Sinica(English letters) 2018年第9期31卷 923-932页

作者： S.S.A.Shah M.g.Jiang D.Wu u.Wasi r.S.Chen The group of Magnesium Alloys and Their Applications Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China university of Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Multi- and unidirectional impact forgings were successfully applied to a （gW94） Mg-rE alloy. The microstructure and texture evolution were investigated systematically. The obtained results indicated that during unidirectional impact forging, a bimodal chain deform microstructure was sustained till last forging pass, whereas { 10-12} extension twins-assisted continuous dynamic recrystallization took place during the multidirectional impact forging （MDIF）. The coalescence and intersection of {10-12} extension twins during MDIF efficiently refined the original coarse grains and led to an almost recrystallized homogeneous microstructure. The texture analysis demonstrated that unidirectional impact forging yielded out the strong basal texture; however, MDIF resulted in non-basal texture, which was attributed to the cooperative effects of continuous DrX, twinning, and MDIF itself during the deformation process.

关键词： Magnesium alloys Forging Twinning recrystallization Texture

Effect of metal fluorides on chromium ions doped bismuth borate glasses for optical applications

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Chinese Physics B 2019年第3期28卷 366-372页

作者： l Haritha K Chandra Sekhar r Nagaraju g ramadevudu Vasanth g Sathe Md.Shareefuddin Department of Physics Telangana University Department of Physics Osmania University Department of Physics Vasavi College of Engineering ugC-DAE Consortium of Scientific research

Fluoride based glasses with composition CaF_2-ZnF_2-Bi_2 O_3-B_2 O_3 doped with chromium ions have been investigated using physical, optical, electron paramagnetic resonance(EPr), Fourier-transform infrared spectroscopy(FTIr), and raman studies. The amorphous nature of samples was confirmed from x-ray diffraction spectra. The density is evaluated from the Archimedes principle and the values of optical band gap and urbach energy values were evaluated from the optical absorption spectra. Thus, molar volume, refractive index, etc., were also evaluated. The observed decrease in density and the optical band gap with CaF2 is explained using the crystalline density of metal fluorides and the ionicity of fluorine ions,respectively. The three peaks near 450 nm, 606 nm, and 720 nm, which are shown in the absorption spectra, are accredited to ~4 A)(2 g) → ~4 T_(1 g), ~4 A_(2 g)→ ~4 T_(2 g), ~4 A_(2 g)→~2 E transitions, respectively. resonance signals at g≈ 4.82 and g≈ 1.99 were observed in EPr spectra which are assigned. FTIr and raman analysis were carried out to examine the impact of metal fluorides on the structure of bismuth borate glasses.

关键词： glasses x-ray diffraction electron paramagnetic resonance Fourier-transform infrared spectroscopy(FTIr) raman spectra

generalized Weighted Morrey Estimates for Marcinkiewicz Integrals with rough Kernel Associated with Schrodinger Operator and Their Commutators

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 77-98页

作者： Ferit gurBuZ Faculty of Education Department of Mathematics EducationHakkari UniversityHakkari 30000Turkey

let l =-△+V(x) be a Schrodinger operator, where △ is the laplacian on r^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their ***, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-littlewood(H-l for short) maximal operators, Bochner-riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.

关键词： Marcinkiewicz operator rough kernel Schrodinger operator generalized weighted Morrey space Commutator BMO

rATIONAl gENErAl SOluTIONS OF HIgHEr OrDEr AlgEBrAIC ODES

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Journal of Systems Science & Complexity 2013年第2期26卷 261-280页

作者： HuANg Yanli Ng l X Chu WINKlEr Franz School of Computer Science and Software Engineering Tianjin Polytechnic University research Institute for Symbolic Computation(rISC) Johannes Kepler University Department of Mathematics Quy Nhon University

This paper generalizes the method of Ng6 and Winkler （2010, 2011） for finding rational general solutions of a first order non-autonomous algebraic ordinary differential equation （AODE） to the case of a higher order AODE, provided a proper parametrization of its solution hypersurface. The authors reduce the problem of finding the rational general solution of a higher order AODE to finding the rational general solution of an associated system. The rational general solutions of the original AODE and its associated system are in computable 1-1 correspondence. The authors give necessary and sufficient conditions for the associated system to have a rational solution based on proper reparametrization of invariant algebraic space curves. The authors also relate invariant space curves to first integrals and characterize rationally solvable systems by rational first integrals.

关键词： Algebraic ODE associated system invariant algebraic space curve rational first integral rational general solution.

Toward an understanding of dwell fatigue damage mechanism of bimodal Ti-6Al-4V alloys

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Journal of Materials Science & Technology 2022年第13期108卷 244-255页

作者： l.r.Zeng l.M.lei X.M.luo g.P.Zhang Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Mechanical Engineering Chengdu UniversityChengdu 610106China AECC Shanghai Commercial Aircraft Engine Manufacturing Co. Ltd.Shanghai 201306China

Dwell fatigue effect is a long-standing problem threatening the long-term service reliability for fan blades and fan disks of an aircraft *** understand the basic mechanism of dwell fatigue damage,pure fatigue and 60 s dwell fatigue properties of bimodal Ti-6Al-4V alloys with different volume fractions of the primaryα(α_(p))phase were examined *** results showed that both pure fatigue and dwell fatigue life decreased with increasing the volume fraction of theα_(p)phase and the dwell fatigue life was lower than the pure fatigue *** quasi-in-situ test results and the quantitative characterization of damage behaviors of the local microstructure units defined by theα_(p)-secondaryα(α_(s))combination reveal that theα_(s)phase close to theα_(p)phase with extensively slip activities was gradually damaged under dwell fatigue loading,while that under pure fatigue loading was undamaged,demonstrating that the dwell loading induced the damage of theα_(s)phase,and further reduced the fatigue life.A stress relaxation-based model is proposed to describe the physical mechanism on dwell fatigue damage of the bimodal Ti-6Al-4V alloy,*** elastic deformation of theα_(s)phase caused by the strain incompatibility would be gradually transformed into plastic deformation during the dwell stage,and thus promotes fatigue *** model provides new insights into the microscopic process of stress/strain transfer between the soft and hard microstructure units under dwell fatigue loading.

关键词： Dwell effect Fatigue damage Stress relaxation Volume fraction of primaryαphase Quasi-in-situ testing

Synthesis and Crystal Structure of Trans-bis(acesulfamato-O)tetraaquazinc(Ⅱ)

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1047-1050页

作者： SAHIN Onur ICBuDAK Hasan B(u|¨)Y(u|¨)Kg(u|¨)Ng(O|¨)r Orhan Department of Physics Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey Department of Chemistry Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey

The title compound, trans-bis（acesulfamato-O）tetraaquazinc（Ⅱ）（I, C8H16N2O12S2Zn）, crystallizes in the triclinic system, space group P1 with a = 5.1638（5）, b = 8.5338（9）, c = 9.9583（9）A, α = 74.325（8）, β = 81.112（7）, γ = 75.800（8）°, V= 407.77（7） A3, Z = 1, F（000） = 236, rint = 0.085, T= 296 K, the final r = 0.029 and wr = 0.078 for 1832 observed reflections with I〉 2σ（0. The ZnⅡcentre resides on a centre of symmetry and has a distorted octahedral geometry. The basal plane is defined by two carbonyl O atoms of two monodentate trans-oriented acesulfamato ligands and two trans-aqua ligands. The axial positions in the octahedron are occupied by two trans-aqua ligands. Intermolecular O-H…O hydrogen bonds produce r22（8） and r22（16） rings, which lead to two- dimensional polymeric chains.

关键词： crystal structure zinc(Ⅱ) octahedral complex hydrogen bonds

A spotlight on dosage and subject selection for effective neuroprotection: exploring the central role of mitochondria

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Neural regeneration research 2025年第4期20卷 1081-1082页

作者： John Mitrofanis Jonathan Stone Michael r.Hamblin Pierre Magistretti Alim-louis Benabid glen Jeffery Fonds Clinatec UniversitéGrenoble AlpesGrenobleFrance School of Medical Science University of SydneySydneyAustralia Faculty of Health Sciences University of JohannesburgJohannesburgSouth Africa King Abdullah university of Science and Technology ThuwalSaudi Arabia Institute of Ophthalmology University College LondonLondonUK

Neurons are notoriously vulnerable cell *** the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological conditions,including stroke,head trauma,and neurodegenerative disease,can generate stress in neurons,affecting their survival and proper *** most neural pathologies,mitochondria become dysfunctional and this plays a pivotal role in the process of cell *** challenge over the last few decades has been to develop effective interventions that improve neuronal homeostasis under pathological *** interventions,often referred to as disease-modifying or neuroprotective,have,however,proved frustratingly elusive,at both preclinical and,in particular,clinical *** this perspective,we highlight two factors that we feel are key to the development of effective neuroprotective *** are:firstly,the choice of dose of intervention and method of application,and secondly,the selection of subjects,whether they be patients or the animal model.

关键词： protective dosage distress

Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural regeneration research 2025年第10期20卷 2913-2914页

作者： William J.Flerlage Mark l.Dell’Acqua Brian M.Cox Fereshteh S.Nugent uniformed Services university of the Health Sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： u.S.Mahabaleshwar g.P.Vanitha l.M.Pérez Emad H.Aly I.Pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection