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Evolution of Microstructure, Residual Stress, and Tensile Properties of Mg–Zn–Y–La–Zr Magnesium Alloy Processed by Extrusion

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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1309-1319页

作者： Huseyin zengin Yunus Turen Muhammet Emre Turan Fatih Ayd?n Department of Metallurgical and Materials Engineering Karabuk University Baliklarkayasi Mevkii Demir Celik Kampusu

The microstructure, texture, residual stress, and tensile properties of Mg–6 Zn–2 Y–1 La–0.5 Zr(wt%) magnesium alloy were investigated before and after extrusion process, which performed at 300 °C and 400 °C. The microstructural characterizations indicated that the as-cast alloy was comprised of α-Mg, Mg–Zn, Mg–Zn–La, and Mg–Zn–Y phases. During homogenization at 400 °C for 24 h, most of the secondary phases exhibited partial dissolution. Extrusion process led to a remarkable grain refi nement due to dynamic recrystallization(DRX). The degree of DRX and the DRXed grain size increased with increasing extrusion temperature. The homogenized alloy did not show a preferential crystallographic orientation, whereas the extruded alloys showed strong basal texture. The extrusion process led to a signifi cant improvement on the compressive residual stress and mechanical properties. The alloy extruded at 300 °C exhibited the highest basal texture intensity, the compressive residual stress and hardness, and yield and tensile strengths among the studied alloys.

关键词： ZK60 Magnesium alloy Residual stress Texture Mechanical properties Extrusion

Note on Lower Triassic Gondolelloid Conodont Rediversifications with Emphasis on the Spathian Recovery

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Journal of Earth Science 2024年第4期35卷 1236-1242页

作者： Ali murat Kilic Department of Geological Engineering Faculty of EngineeringBalikesir UniversityBalikesir99100Turkey

Conodonts,as a biotic group,next to ammonoids,pollen and spores,crustaceans and vertebrates,provide proxy clues for environment and age assessments of the rocks in which they *** are widely used for Triassic marine ***,there are various discussions about their multielement taxonomy and evolutionary lineages(e.g.,generation,speciation).Although first studies reported that most Triassic conodont species were unimembrate,studies carried out in the following years maintained that all Triassic conodonts were *** statistical reconstructions of a number of Triassic apparatuses were attempted,the discovery of fused clusters and natural assemblages has subsequently demonstrated that Triassic conodonts are indeed multimembrate,and all of the elements exist together in the same *** present paper aims to clarify the evolutionary relationship and array of some Lower Triassic *** dagisi *** described.

关键词： Triassic Spathian conodont Columbitella Siberia environmental geology

Chromium Substitution Effect on the Magnetic Structure of Iron Oxides

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Chinese Physics Letters 2012年第5期29卷 217-220页

作者： Osman murat Ozkendir Mersin University Tarsus Technical Faculty of EducationTarsusTurkey UVSOR FacilityInstitute for Molecular ScienceOkazaki 444-8585Japan

The local magnetic and electronic structures of chromium substituted iron oxide polycrystalline samples are investigated via Fe L-edge x-ray absorption near-edge structural and magnetic circular dichroism measurements.A strong dependence of atomic magnetic levels on the applied external magnetic field is *** magnetic behavior of Cr-doped iron oxides are determined to be dominantly governed by the d-d hybridization between Fe and Cr valence *** addition,the formation of CrO_(2) and Cr_(2)O_(3) chromium oxide clusters in the sample are observed to determine the magnetic ordering,***-ferromagnetic or ferromagnetic with the changing external magnetic *** results highly agree with the previous studies.

关键词： chromium ferromagnetic magnetic

Anisian(Middle Triassic)Conodonts of the Kocaeli Triassic,Western Turkey

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Journal of Earth Science 2021年第3期32卷 616-632页

作者： Ali murat Kilic Department of Geological Engineering Faculty of EngineeringBalikesir UniversityBalikesirTurkey

The present study of Anisian(Middle Triassic)conodonts from the Kocaeli Peninsula(western Turkey)encompasses over 10 species of the families Gondolellidae and Gladigondolellidae,providing Early and Middle Triassic time constraints,Chiosella timorensis(Nogami,1968);Cornudina oezdemirae Gedik,1975;Gladigondolella tethydis(Huckriede,1958);Neostrachanognathus tahoensis Koike,1998;Paragondolella aegaea(Bender,1970);Paragondolella bulgarica Budurov and Stefanov,1975;Nicoraella kockeli(Tatge,1956);***(Sudar and Budurov,1979),and Gladigondolella *** established are Paragondolella hirschii *** and Budurov;*** *** ,Budurov,Petrunova and Mirauta;and *** ***.K?l??.The Kocaeli Anisian conodonts show a faunal affinity with *** present Anisian fauna is characteristic of the *** strong homeomorphy that characterizes the Anisian in western North America is discussed.

关键词： Triassic Anisian Aegean Bithynian conodonta Gebze(Kocaeli)

Synthesis, Spectral Analysis and Antimicrobial Activity of New Pd (Ⅱ) Complexes Involving 5,6-Dimethylbenzimidazole

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Chemical Research in Chinese Universities 2023年第6期39卷 968-975页

作者： murat TÜRKYILMAZ murat DÖNMEZ Özlen ALTUN Department of Chemistry Trakya University22030 EdirneTurkey

In this study,firstly,3-bromopropanenitrile(2a),ethyl bromoacetate(2b),and 2-bromoethan-1-amine(2c)were added to 5,6-dimethylbenzimidazole(1)and symmetrically-connected N-heterocyclic carbenes(NHC)[(3a-3c)]were ***,the NHC precursor compounds were reacted with PdCl2 and Pd(Ⅱ)-NHC complexes[(4a—4c)]were *** synthesized NHC precursors(3a-3c)and Pd(Ⅱ)-NHC complexes(4a—4c)were characterized by different spectroscopic *** antibacterial activities of these products were measured against bacteria and fungus with the disc diffusion ***(Ⅱ)-NHC complexes had higher antibacterial activity than the NHC *** synthesized compounds showed antimicrobial activity with different properties from each *** vitro biological activities of salts and metal complexes on selected bacteria were determined by the broth dilution method based on Clinical and Laboratory Standards Institute guidelines.1,3-Bis-(2-hydroxyethyl)imidazolinium bromide and 3-(2-ethoxy-2-oxoethyl)-1-(3-aminopropyl)-^(1)H-imidazole-3-ium bromide had activity against Escherichia coli.

关键词： N-Heterocyclic carbene Palladium(Ⅱ)-NHC complex Structural analysis Antimicrobial activity

Transient Temperature Analysis for Industrial AC Arc Furnace Bottom

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Journal of Iron and Steel Research International 2004年第6期11卷 1-4页

作者： ■ murat Tun Development Bank of Turkey Ankara 06100Turkey Yeditepe University Istanbul 81120Turkey

Heat losses from the furnaces depend on the design and size. The surface heat loss from the bottom of an industrial AC electric arc furnace (EAF) possesses an important fraction of overall losses. So in this study the transient temperature variation at the bottom of the EAF was investigated. The transient temperature analysis was carried out using MATLAB computer program. T=T(r, t) for different bottom lining layers was depicted.

关键词： electric arc furnace steel production industrial system transient temperature analysis

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Comparison of the Retinomax hand-held autorefractor versus table-top autorefractor and retinoscopy

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 491-495页

作者： Ibrahim Tuncer Mehmet Ozgur zengin Eyyup Karahan Alfagoz Eye Center Department of Ophthalmology Izmir University Faculty of Medicine

AIM:To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and ***:The study included 127 patients(mean age96.7mo,range 21 to 221).Retinomax(Rmax)(Nikon Inc.,Japan)was used to obtain noncycloplegic *** cycloplegia,refraction was measured with Rmax,table-top autorefractor(TTR)(Nikon NRK 8000,Inc.,Japan)and *** values of sphere,spherical equivalent,cylinder and axis of cylinder were recorded for Rmax,TTR and retinoscopy in each *** results were analyzed ***:The mean spheric values(SV),spherical equivalent values(SEV)and cylindrical values(CV)of the noncycloplegic Rmax(SV:0.64 D,SEV:0.65 D and CV:0.03 D,respectively)were found to be significantly lower than cycloplegic TTR(1.43 D,1.38 D and 0.3 D;P=0.012,P=0.011 and P=0.04,respectively)and retinoscopy(1.34 D,1.45 D and 0.23 D;P=0.04,P=0.002 and P=0.045,respectively).Mean cycloplegic SV,SEV,CV were not significantly different between Rmax and TTR,Rmax and retinoscopy,TTR and *** or noncycloplegic axis values were not different between any ***:Rmax may be used successfully as a screening tool but may not be accurate enough for actual spectacle *** Rmax measurements may be able to identify refractive error in children because of approximate results to retinoscopy.

关键词： autorefractor hand-held refractors retinoscopy Retinomax

SYNTHESIS, CHARACTERIZATION AND SOME PROPERTIES OF EPOXY RESINS CONTAINING AZOMETHINE BONDING

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Chinese Journal of Polymer Science 2013年第8期31卷 1087-1095页

作者： smet Kaya murat Gül anakkale Onsekiz Mart University Faculty of Sciences and Arts Department of Chemistry Polymer Research Laboratory

New epoxy resins were prepared from hydroxyl substituted Schiff base monomers in two steps. The first step is based on the synthesis of hydroxyl substituted Schiffbase monomers via condensation reaction. The second step includes the reaction between Schiff base monomers with cpichlorohydrine （EPC） to obtain epoxy resins. The structures of resulting compounds were confirmed by FTIR and H-NMR. TG-DTA and DSC measurements were made for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems in acidic, alkaline and organic solvents were determined for coating applications. HC1 （aqueous solution, 10%）, NaOH （aqueous solution, 10%）, DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data show that the synthesized resins have good chemical resistance against various acid, alkaline and common organic solvents.

关键词： Epoxy resin Thermal analysis Poly(imine)s.

Plume diagnostics of BUSTLab microwave electrothermal thruster using Langmuir and Faraday probes

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Plasma Science and Technology 2019年第4期21卷 145-154页

作者： M Serhan YILDIZ murat CELIK Turkish Air Force Academy.Istanbul 34149.Turkey Bogazici University Islanbul 34342Turkey

This study presents the Langmuir and Faraday probe measurements conducted to determine the plume characteristics of the BUSTLab microwave electrothermal thruster(MET).The thruster,designed to operate at 2.45 GHz frequency,is run with helium,argon and nitrogen gases as the *** the measurements,the propellant volume flow rate and the delivered microwave power levels are *** with nitrogen gas revealed certain operation regimes where a very luminous plume is *** the use of in-house-built Langmuir probes and a Faraday probe with guard ring,thruster plume electron temperature,plasma density and ion current density values are measured,and the results are *** measurements show that MET thruster plume effects on spacecraft will likely be similar to those of the arcjet *** is observed that the measured plume ion flux levels are very low for the high volume flow rates used for the operation of this thruster.

关键词： microwave electrothermal thruster plasma diagnostics plume plasma faraday probe