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Effect of heat Treatment on Microstructure,Mechanical Properties and Fracture Behaviour of Ship and Dual Phase Steels

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Journal of Iron and Steel Research International 2011年第8期18卷 65-72页

作者： Fatih hayat hüseyin Uzun Metallurgy and Materials Engineering Department Engineering FacultyKarabuk University Metallurgy Education Department Technical Education FacultySakarya University

Grade A （GA） and high strength steel Dh36 ship steels possessing different chemical compositions were used, and strength properties of GA steel and Dh36 steel were compared. Additionally, 4 types of dual phase （DP） steels with different martensite volume fractions （MVFs） were produced from GA steel by means of heat treatment and they were compared with other steels through conducting mierostructure, microhardness, tensile and impact tests. The fracture surfaces of specimens （Dh36, GA and DP steels） exposed to tensile and Charpy impact tests were investigated by scanning electron microscope. Furthermore, it was found that the specimens quenched from 800 and 900℃ had better strength than Dh36 steel. The tensile test results indicated that the tensile strength of DP steel water quenched from 900℃ was 3 times that of GA steel and twice that of Dh36 steel.

关键词： Grade A ship steel Dh36 ship steel dual phase steel martensite mechanical property fracture

Effects of Annealing on Thermoluminescence Peak Positions and Trap Depths of Synthetic and Natural Quartz by Means of the Various heating Rate Method

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Chinese Physics Letters 2012年第8期29卷 250-252页

作者： hüseyin Toktamiş A.Necmeddin Yazici Department of Engineering Physics University of Gaziantep27310 GaziantepTurkey

Some environmental and experimental variables such as annealing process alter the structure of glow curves of some thermoluminescence *** investigate the effects of annnealing on thermoluminescence peaks of synthetic and natural quartz at different heating *** experimental results show that the peak temperatures of glow peaks in annealed samples shift to higher temperature *** amount of shifting is higher for low temperature peaks than high temperature *** trap depths of annealed and unannealed samples of both synthetic and natural quartz are also obtained by various heating rate *** is noted that the annealing process affects the trap depth of all glow peaks and the trap depth increases after the annealing process.

关键词： annealed annealing quartz

An Active Image Forgery Detection Approach Based on Edge Detection

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Computers, Materials & Continua 2023年第4期75卷 1603-1619页

作者： hüseyin Bilal Macit Arif Koyun Department of IT Systems and Technologies Mehmet Akif Ersoy UniversityBucak Z.T.School of Applied Technology and BusinessBurdur15300Türkiye Department of Computer Engineering Suleyman Demirel UniversityEngineering FacultyIsparta32200Türkiye

Recently, digital images have become the most used data, thanks tohigh internet speed and high resolution, cheap and easily accessible digitalcameras. We generate, transmit and store millions of images every *** of these images are insignificant images containing only personal ***, in many fields such as banking, finance, public institutions,and educational institutions, the images of many valuable objects like IDcards, photographs, credit cards, and transaction receipts are stored andtransmitted to the digital environment. These images are very significantand must be secured. A valuable image can be maliciously modified by anattacker. The modification of an image is sometimes imperceptible even by theperson who stored the image. In this paper, an active image forgery detectionmethod that encodes and decodes image edge information is proposed. Theproposed method is implemented by designing an interface and applied on atest image which is frequently used in the literature. Various tampering attacksare simulated to test the fidelity of the method. The method not only notifieswhether the image is forged or not but also marks the tampered region ofthe image. Also, the proposed method successfully detected tampered regionsafter geometric attacks, even on self-copy attacks. Also, it didn’t fail on JPEGcompression.

关键词： Image forgery image tampering edge detection

Petrology and Geochemistry of Post-Collisional Early Miocene Volcanism in the Karacadag Area(Central Anatolia,Turkey)

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1100-1117页

作者： Krsad ASAN hseyin KURT Department of Geological Engineering Selcuk University

Early Miocene（ca.21-18 Ma） volcanism in the Karacadag area comprises three groups of volcanic rocks:（1） calcalkaline suite（andesitic to rhyolitic lavas and their pyroclastics）,（2） mildly-alkaline suite（alkali basalt,hawaiite,mugearite,benmoreite and trachydacite）,and（3） a single trachyandesitic flow *** observations,40Ar/39Ar ages and geochemical data show that there was a progressive temporal transition from group 1 to 3 in a post-collisional tectonic *** calcalkaline suite rocks with medium-K in composition resemble those of subduction-related lavas, whereas the mildly-alkaline suite rocks having a sodic tendency（Na2O/K2O=l.5-3.2） resemble those of within-plate *** element and Sr-Nd isotopic characteristics of the suites suggest that the lithospheric mantle beneath the Karacadag area was heterogeneously enriched by two processes before collision:（1） enrichment by subduction-related processes,which is important in the genesis of the calcalkaline volcanism,（2） enrichment by small degree melts from the astenosphere,which dominates the mildly alkaline *** of the enriched lithosphere by either delamination following collision and uplift or removal of the subducted slab following subduction and collision（i.e.,slab breakoff） is the likely mechanism for the initiation of the post-collision volcanism.

关键词： post-collision calcalkaline Sr-Nd isotopes Karacadag Central Anatolia

A Novel Method to Improve the Electrochemical Performance of LiMn_2O_4 Cathode Active Material by CaCO_3 Surface Coating

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Journal of Materials Science & Technology 2011年第5期27卷 415-420页

作者： halil Sahan hüseyin Gktepe Saban Patat Deparment of Chemistry Science of FacultyUniversity of Erciyes

Spinel LiMn204 was synthesized by glycine-nitrate method and coated with CaCO3 in order to enhance the electrochemical performance at room temperature （25℃） and 55℃. The uncoated and CaCO3-coated LiMn204 materials were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical tests. XRD and SEM results indicated that CaCO3 particles encapsulated the surface of the LiMn204 without causing any structural change. The charge-discharge tests showed that the specific discharge capacity fade of pristine electrode at 25 and 55℃ were 25.5% and 52%, respectively. however, surface modified cathode shows 7.4% and 29.5% loss compared to initial specific discharge capacity at 70th cycle for 25 and 55~C, respectively. The improvement of electrochemical performance is attributed to suppression of Mn2＋ dissolution into electrolyte via CaCO3 layer.

关键词： LiMn204 CaC03 surface coating Cathode material Capacity fade Cycleability Lithium ion battery

Ground State Energy Calculations of Isoelectronic Series of he in Double-Zeta Approximation Using Coulomb Potential with Noninteger Indices

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Chinese Physics Letters 2008年第3期25卷 896-898页

作者： GUSEINOV I. Israfil AKSU hüseyin Department of Physics Faculty of Arts and Sciences Onsekiz Mart University Canakkale Turkey

Using formulae for one- and two-electron integrals of Coulomb interaction potential fk （r） = r^-k with non-integer indices k established by one of the authors with the help of complete orthonormal sets of ψ^α-exponential-type orbitals （α = 1, 0,-1,-2,…）, we perform the calculations for isoelectronic series of the he atom containing nuclear charges from 2 to 10, where k = 1 - μ （-1 〈 μ 〈 0）. For this purpose we have used the double-zeta approximation, the configuration interaction and coupled-cluster methods employing the integer-n Slater-type orbitals as basis sets. It is demonstrated that the results of calculations obtained are better than the numerical hartree-Fock values.

关键词： SLATER-TYPE ORBITALS MULTICENTER INTEGRALS ONE-ELECTRON OPEN-ShELLS SYSTEMS INTEGER ATOMS

Effects of geoclimatic factors on the variability in Pinus pinea cone, seed, and seedling traits in Turkey native habitats

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Ecological Processes 2020年第1期9卷 648-660页

作者： Safa Balekoglu Servet Caliskan hüseyin Dirik Faculty of Forestry Silviculture DepartmentIstanbul University-CerrahpasaBahcekoySariyerIstanbulTurkey

Background:Stone pine(Pinus pinea L.)is harvested for its edible *** is an important forest tree species,and also plays an important role in *** afforestation activities strongly depend on the quality of seeds and *** eastern native populations of stone pine were analyzed,in terms of their geographical and climatic parameters,in order to identify their cone,seed,pine nut,and seedling *** this regard,we aimed to contribute to the reforestation,yield,and breeding of this ***:All native populations occur in the sub-humid bioclimatic zone,according to Emberger’s bioclimatic classification,ranging 74.7-63.2 of Emberger’s Q Index value(Q),which synthesizes humidity and temperature,with lower values indicating more arid *** regard to geographical factors,altitude was found to have the greatest effect on cone diameter and seed weight,while there was a weak correlation of cone,seed,and pine nut dimension with longitude and *** terms of climatic factors,Q and mean of the maximum temperature of June,July,and August(ME)were found to be the main drivers behind significant effects in cone,seed,and pine nut morphometric *** most negative effect on seed number cone−1(r:−0.897),pine nut number cone−1(r:−0.923),pine nut yield(r:−0.903),and pine nut weight(r:−0.878)was Q,whereas cone diameter,seed length,and seed weight were positively correlated with the ME(r:0.939,r:0.889,and r:0.866,respectively).Cone and seed diameter and seed weight increased with decreasing summer drought index(r:−0.806,r:−0.846,and r:−0.866,respectively).Rainfall in the June of the third year prior to harvest time(RJ)had a negative effect on the percentage of sound seeds per *** rainfall in the third year prior to harvest time(AR)significantly affected pine nut weight(r:0.889),although rainfall during summer had a negative *** empty seed ratio of the different populations ranged from 20 to 68%,while considering

关键词： Bioclimatic zone Emberger Mediterranean Stone pine variation

Comparisons of the suture zones along a geotraverse from the Scythian Platform to the Arabian Platform

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Geoscience Frontiers 2014年第6期5卷 855-875页

作者： Ali Yilmaz Shota Adamia hüseyin Yilmaz Cumhuriyet University Engineering FacultyDepartment of Environmental EngineeringKayseri StreetCU.CampusTR-58140 SivasTurkey Nodia Institute of Geophysics 1M.Alexidze Str.0195TbilisiGeorgia Cumhuriyet University Engineering FacultyDepartment of Geophysical EngineeringTR-58140 SivasTurkey

The area from the Greater Caucasus to the southeast Turkey is characteri：;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System （PTCAS）, the Anatolian-lranian and the Arabian Platforms. The aim of this paper is to define these continental blocks and describe and also compare their boundary relationships along the suture zones. The Scythian Platform displays the evidence of the hercynian and Alpine orogens. This platform is separated from the PTCAS by the Greater Caucasus Suture Zone. The incipient collision began along this suture zone before middle-late Carboniferous whereas the final collision occurred before Oligocene. The PTCAS can be divided into four structural units：（1） the Georgian Block - northern part of the Pontian-Transcaucasian island-arc, （2） the southern and eastern Black Sea Coast-Adjara-Trialeti Unit, （3） the Artvin-Bolnisi Unit, comprising the northern part of the southern Transcaucasus, and （4） the Imbricated Bayburt-Garabagh Unit. The PTCAS could be separated from the Anatolian Iranian Platform by the North Anatolian-Lesser Caucasus Suture （NALCS） zone. The initial collision was developed in this suture zone during Senonian-early Eocene and final collision before middle Eocene or Oligocene-Miocene. The Anatolian-lranian Platform （AIP） is made up of the Tauride Platform and its metamorphic equivalents together with Iranian Platform. It could be separated from the Arabian Platform by the Southeastern Anatolian Suture （SEAS） zone. The collision ended before late Miocene along this suture zone. The southernmost continental block of the geotraverse is the Arabian Platform, which constitutes the northern part of the Arabian-African Plate. This platform includes a sequence from the Precambrian felsic volcanic and clastic rocks to the Campanian-early Maastrichtian fiyschoidal clastics. All the suture zones include MORB and SSZ-types ophiolites in different ages. however, the ages of

关键词： Scythian Plattorm Arabian Platform Suture zones Ceotraverse

Influence of Confined Concrete Models on the Seismic Response of RC Frames

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Structural Durability & health Monitoring 2024年第3期18卷 197-222页

作者： hüseyin Bilgin Bredli Plaku Department of Civil Engineering EPOKA UniversityTirana1039Albania

In this study, the influence of confined concrete models on the response of reinforced concrete structures is investigatedat member and global system levels. The commonly encountered concrete models such as Modified Kent-Park, Saatçioğlu-Razvi, and Mander are considered. Two moment-resisting frames designed according to thepre-modern code are taken into consideration to reflect the example of an RC moment-resisting frame in thecurrent building stock. The building is in an earthquake-prone zone located on Z3 Soil Type. The inelasticresponse of the building frame is modelled by considering the plastic hinges formed on each beam and columnelement for different concrete classes and stirrups spacings. The models are subjected to non-linear static *** differences between confined concrete models are comparatively investigated at both reinforced concretemember and system levels. Based on the results of the comparative analysis, it is revealed that the column behaviouris mostly influenced by the choice of model, due to axial loads and confinement effects, while the beams areless affected, and also it is observed that the differences exhibited in the moment-curvature response of columncross-sections do not significantly affect the overall behaviour of the global system. This highlights the critical roleof model selection relative to the concrete strength and stirrup spacing of the member.

关键词： Non-linear static analysis moment-curvature relationships plastic hinges concrete confinement models seismic action