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international Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 946-952页

作者： Mehmet Deniz turan Department of Metallurgical and Materials Engineering Firat University

The dissolution of copper and iron from chalcopyrite concentrate in the presence of ammonium persulfate(APS)and ammonium hydroxide was investigated under atmospheric leaching *** were designed by central composite design(CCD).Under the optimum leaching conditions((NH4)2S2O8 concentration=328 g/L;NH4OH addition=16vol%;leaching temperature=321 K(48℃);leaching time=120 min;liquid-to-solid ratio=16;stirring speed=400 r/min),selective leaching was achieved.98.14%of the copper was leached,whereas iron did not pass into the solution.X-ray diffraction analysis of the leaching residue showed that iron compounds were *** the leaching results,the fact that the leaching process does not include uneconomical leaching stages such as extended milling/mechanical activation or high pressures/temperatures,and the low copper dissolution conditions,the attained selective leaching yield may be remarkable.

关键词： leaching complex reaction selectivity copper chalcopyrite

Distinguished Connections on Finsler Algebroids

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Chinese Annals of Mathematics,Series B 2021年第1期42卷 41-68页

作者： Esmaeil PEYGHAN Aydin GEZER inci GULTEKiN Department of Mathematics Faculty of ScienceArak UniversityArak38156-8-8349Iran Ataturk University Faculty of ScienceDepartment of Mathematics25240ErzurumTurkey

Considering the prolongation of a Lie algebroid,the authors introduce Finsler algebroids and present important geometric objects on these *** endomorphisms like conservative and Barthel,Cartan tensor and some distingu... 详细信息

关键词： Chern-Rund connection Distinguished connections Finsler algebroid Hashiguchi connection Lie algebroid

Suppressing the ferroelectric switching barrier in hybrid improper ferroelectrics

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npj Computational Materials 2020年第1期6卷 287-296页

作者： Shutong Li turan Birol Department of Chemical Engineering and Materials Science University of MinnesotaMinneapolisMN 55455USA

integration of ferroelectric materials into novel technological applications requires low coercive field materials,and consequently,design strategies to reduce the ferroelectric switching *** this first principles study,we show that biaxial strain,which has a strong effect on the ferroelectric ground states,can also be used to tune the switching barrier of hybrid improper ferroelectric Ruddlesden–Popper *** identify the region of the strain-tolerance factor phase diagram where this intrinsic barrier is suppressed,and show that it can be explained in relation to strain-induced phase transitions to nonpolar phases.

关键词： ferroelectric transitions explained

Unveiling the reaction products in heat treated Si3N4–Ti joined ceramics by transmission electron microscopy

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Journal of Advanced Ceramics 2019年第4期8卷 500-508页

作者： Orkun TUNCKAN Hilmi YURDAKUL Servet turan Faculty of Aeronautics and Astronautics Eskisehir Technical University rafet Kayis Faculty of Engineering Department of Metallurgical and Materials EngineeringAlanya Alaaddin Keykubat University Faculty of Engineering Department of Materials Science and EngineeringEskisehir Technical University

Joining is a crucial process for the production of complex-shaped advanced engineering *** understanding of ceramic–metal interfaces during joining or following heat-treatment steps is therefore of important concern in designing the new *** discharge joining(CDJ)method was firstly carried out to compose the ceramic–metal joint material by silicon nitride(Si3N4)–titanium(Ti)***,heat treatment was performed on the Si3N4-Ti joints in air atmosphere at 1000℃temperature to reveal the interface reactions and *** layer that occurred between the Si3N4 and Ti interfaces and new phase formations were examined by transmission electron microscopy(TEM)-based various imaging and chemical analysis *** transparent samples for TEM characterization were prepared by focused ion beam(FiB)milling and lifting *** on the detailed TEM results,Si and N diffusion arising from the Si3N4 ceramic was observed towards Ti metal foil side and further interacted with Ti *** upshot of current diffusion was that Ti3N2 reaction layer with 50 nm thickness was formed at the interface while titanium silicon nitride(Ti6Si3N)matrix phase including dendritic-shaped Ti2 N grains occurred in the Ti *** is believed that our TEM-based microscopy results not only provide the knowledge on ceramic–metal joint materials by CDJ method,but also contribute new insights on the development of various new joint systems.

关键词： capacitor discharge joining(CDJ) Si3N4 Ti transmission electron microscopy(TEM)

Urine products of bone breakdown as markers of bone resorption and clinical usefulness of urinary hydroxyproline:an overview

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Chinese Medical Journal 2004年第2期17卷 291-295页

作者： Baris Simsek zgülKaracaer inci Karaca Department of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Prosthodontics Faculty of Dentistry University of Gazi Emek Ankara Turkey

Purpose The purpose of this study is to review the urine products of bone breakdown as markers of bone resorption and usefulness of urinary hydroxyproline.Data Related researches published in 1985 -2000 were systematically reviewed.Results Bone markers could be used for early diagnosis of bone metabolic diseases. Biochemical markers of bone resorption that reflect osteoclast activity and/or collagen degradation provide a new and potentially important clinical tool for the assessment and monitoring of bone metabolism. Assessment of bone resorption can be achieved with measurement of urinary hydroxylysine glycosides, urinary excretion of the collagen pyridinium cross-links, urinary excretion of type i collagen telopeptide breakdown products (cross-linked telopeptides) and urinary hydroxyproline.Conclusion Urinary hydroxyproline has been in use as a marker of bone resorption, but it lacks sensitivity and specificity. it is a modified aminoacid that is a metabolic product of collagen breakdown. Hydroxyproline may be released either free or with fragments of the collagen molecule attached during bone resorption, and it is also liberated by the breakdown of complement and nonskeletal collagen.

关键词： bone resorption marker biochemical markers hydroxyproline collagen breakdown hydroxylysine glycosides pyrolidine deoxypyrolidine N-tebpeptides C-telopeptides

Mathematical Modelling and 3D FEM Analysis of the influence of initial Stresses on the ERR in a Band Crack’s Front in the Rectangular Orthotropic Thick Plate

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Computers, Materials & Continua 2017年第3期53卷 249-270页

作者： Arzu turan Dincel Surkay DAkbarov Yildiz Technical University Department of Mathematical EngineeringDavutpasa Campus34220EsenlerIstanbul-Turkey Yildiz Technical University Faculty of Mechanical EngineeringDepartment of Mechanical EngineeringYildiz Campus34349BesiktasIstanbul-Turkey institute of Mathematics and Mechanics of the National Academy of Science of Azerbaijan 37041BakuAzerbaijan

This paper deals with the mathematical modelling and 3D FEM study of the energy release rate(ERR)in the band crack’s front contained in the orthotropic thick rectangular plate which is stretched or compressed initially before the loading of the crack's edge *** initial stretching or compressing of the plate causes uniformly distributed normal stress to appear acting in the direction which is parallel to the plane on which the band crack is *** the appearance of the initial stress in the plate it is assumed that the crack's edge planes are loaded with additional uniformly distributed normal forces and the ERR caused with this additional loading is *** corresponding boundary value problem is formulated within the scope of the so-called 3D linearized theory of elasticity which allows the initial stress on the values of the ERR to be taken into *** results on the influence of the initial stress,anisotropy properties of the plate material,the crack’s length and its distance from the face planes of the plate on the values of the ERR,are presented and *** particular,it is established that for the relatively greater length of the crack’s band,the initial stretching of the plate causes a decrease,but the initial compression causes an increase in the values of the ERR.

关键词： Band crack energy release rate stress intensity factor initial stress orthotropic material rectangular plate 3D FEM

A new approach for prediction of the wear loss of PTA surface coatings using artificial neural network and basic,kernel-based,and weighted extreme learning machine

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Friction 2020年第6期8卷 1102-1116页

作者： Mustafa ULAS Osman ALTAY turan GURGENC Cihan OZEL Department of the Software Engineering Firat UniversityElazig 23119Turkey Department of the Automotive Engineering Firat UniversityElazig 23119Turkey Department of the Mechanical Engineering Firat UniversityElazig 23119Turkey

Wear tests are essential in the design of parts intended to work in environments that subject a part to high *** tests involve high cost and lengthy experiments,and require special test *** use of machine learning algorithms for wear loss quantity predictions is a potentially effective means to eliminate the disadvantages of experimental methods such as cost,labor,and *** this study,wear loss data of AiSi 1020 steel coated by using a plasma transfer arc welding(PTAW)method with FeCrC,FeW,and FeB powders mixed in different ratios were obtained experimentally by some of the researchers in our *** mechanical properties of the coating layers were detected by microhardness measurements and dry sliding wear *** wear tests were performed at three different loads(19.62,39.24,and 58.86 N)over a sliding distance of 900 *** this study,models have been developed by using four different machine learning algorithms(an artificial neural network(ANN),extreme learning machine(ELM),kernel-based extreme learning machine(KELM),and weighted extreme learning machine(WELM))on the data set obtained from the wear test *** R2 value was calculated as 0.9729 in the model designed with WELM,which obtained the best performance among the models evaluated.

关键词： wear loss prediction surface coating plasma transferred arc welding artificial neural network extreme learning machine

MULTiPLiERS AND TENSOR PRODUCTS OF L(p,q) LORENTZ SPACES

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Acta Mathematica Scientia 2007年第1期27卷 107-116页

作者： Hakan Avci A.turan Gürkanli Department of Mathematics Faculty of Arts and Sciences Ondokuz Mayis University55139KurupelitSamsunTURKEY

Let G be a locally compact abelian group. The main purpose of this article is to find the space of multipliers from the Lorentz space. L（p1, q1）（G） to L（p＇2, q＇2）（G）. For this reason, the authors define the space A p1,q1^ p2,p2（G）, discuss its properties and prove that the space of multipliers from L（p1, q1）（G） to L（p＇2, q＇2）（G） is isometrically isomorphic to the dual of A p1,q1^p2,q2 （G）.

关键词： Lorentz space Banach module multiplier

Prediction of wear loss quantities of ferro-alloy coating using different machine learning algorithms

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Friction 2020年第1期8卷 107-114页

作者： Osman ALTAY turan GURGENC Mustafa ULAS Cihan OZEL Software Engineering Firat UniversityElazig 23119Turkey Automotive Engineering Firat UniversityElazig 23119Turkey Mechanical Engineering Firat UniversityElazig 23119Turkey

in this study,experimental wear losses under different loads and sliding distances of AiSi 1020 steel surfaces coated with(wt.%)50FeCrC‐20FeW‐30FeB and 70FeCrC‐30FeB powder mixtures by plasma transfer arc welding were *** dataset comprised 99 different wear amount measurements obtained experimentally in the *** linear regression(LR),support vector machine(SVM),and Gaussian process regression(GPR)algorithms are used for predicting wear quantities.A success rate of 0.93 was obtained from the LR algorithm and 0.96 from the SVM and GPR algorithms.

关键词： surface coating plasma transfer arc(PTA)welding wear prediction machine learning algorithms

Soil quality assessment for desertification based on multi-indicators with the best-worst method in a semi-arid ecosystem

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Journal of Arid Land 2023年第7期15卷 779-796页

作者： Orhan DENGiZ inci demiraĞturan Department of Soil Science and Plant Nutrition Faculty of AgricultureOndokuz Mayıs UniversitySamsun-55139Turkey Department of Geography Faculty of EconomicAdministrative and Social SciencesSamsun UniversitySamsun-55030Turkey

Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQi) model in the semi-arid ?orum Basin, situated between the Black Sea and Anatolia Region, Central Turkey. The primary aims of the study are:(1) to determine SQi values of the micro-basin in terms of land degradation and ***, the best-worst method(BWM) was used to determine the weighting score for each parameter;(2) to produce the soils' spatial distribution by utilizing different geostatistical models and GiS(geographic information system) techniques;and(3) to validate the obtained SQi values with biomass reflectance values. Therefore, the relationship of RE-OSAVi(red-edge optimized soil-adjusted vegetation index) and NDVi(normalized difference vegetation index) generated from Sentinel-2A satellite images at different time series with soil quality was examined. Results showed that SQi values were high in the areas that had almost a flat and slight slope. Moreover, the areas with high clay content and thick soil depth did not have salinity problems, and were generally distributed in the middle parts of the basin. However, the areas with a high slope, poor vegetation, high sand content, and low water holding capacity had low SQi ***, a statistically high positive correlation of RE-OSAVi and NDVi indices with soil quality was found, and NDVi had the highest correlative value for June(R~2=0.802) compared with RE-OSAVi.

关键词： soil quality land degradation desertification best-worst method remote sensing