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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

THIRD-ORDER DIFFERENTIAL SUBORDINATION RESULTS FOR ANALyTIC FUNCTIONS INVOLVING THE GENERALIZED BESSEL FUNCTIONS

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Acta Mathematica Scientia 2014年第6期34卷 1707-1719页

作者：汤获 Erhan deniz School of Mathematics and Statistics Chifeng University School of Mathematical Sciences Beijing Normal University Department of Mathematics Faculty of Science and LettersKafkas University

In the present paper, we derive some third-order differential subordination results for analytic functions in the open unit disk, using the operator Bcκf by means of normalized form of the generalized Bessel functions of the first kind, which is defined as z（Bκ＋1^c f（z））′= κBκ^c f（z）-（κ- 1）Bκ＋1^c f（z）,where b, c, p ∈ C and κ = p ＋（b ＋ 1）/2 ∈ C ／ Z0^-（Z0^-= {0,-1,-2, … }）. The results are obtained by considering suitable classes of admissible functions. Various known or new special cases of our main results are also pointed out.

关键词： differential subordination univalent functions Hadamard product admissible functions generalized Bessel functions

Characterization and corrosion studies of ternary Zn–Ni–Sn alloys

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 74-82页

作者： Reyhan Solmaz B.deniz Karahan Department of Metallurgical and Materials Engineering Istanbul Technical UniversityMaslakIstanbul 34469Turkey School of Engineering and Natural Sciences Istanbul Medipol UniversityBeykozIstanbul 34810Turkey

Nine distinct zinc-nickel-tin films with different compositions have been galvanostatically electrodeposited. The films have been characterized by scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS). Their corrosion potentials and densities have been estimated using Tafel extrapolation. Next, the electrochemical behaviors of the films(deposited through the electrolytes containing 0, 6, 8, and10 g/L SnCl2?6H2O) have been examined based on cyclic voltammetry(CV) measurements. Further, these films have been immersed in 3.5 wt%Na Cl solution for 1 h, 1 d, 7 d, 14 d, 28 d, and 42 d followed by application of Tafel extrapolation and electrochemical impedance spectroscopy(EIS) tests on each aged sample. Finally, to analyze the morphologies and the compositions of the oxide films covering the surfaces of the 42-d aged films, FT-IR and SEM analyses have been performed. The results indicated that the Zn–Ni–Sn film produced through the bath including 6g/L SnCl2?6H2 O exhibits superior corrosion resistance because of the high Ni content in the presence of Sn that promotes the barrier protection capability of the deposit.

关键词： ternary alloys corrosion electro galvanizing anomalous deposition Tafel

Thermal entanglement in the mixed three-spin XXZ Heisenberg model on a triangular cell

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Chinese Physics B 2014年第5期23卷 73-79页

作者： Seyit deniz Han Ekrem Aydiner Department of Physics Istanbul University

We numerically investigate the thermal entanglements of spins （1/2, 1） and spins （1/2, 1/2） in the three-mixed （1/2, 1, 1/2） anisotropic Heisenberg XXZ spin system on a simple triangular cell under an inhomogeneous magnetic field. We show that the external magnetic field induces strong plateau formation in the pairwise thermal entanglement for fixed parame-ters of the Hamiltonian in the cases of ferromagnetic and antiferromagnetic interactions. We also .observe an unexpected critical point at finite temperature in the thermal entanglement of spins （1/2, 1） for the antiferromagnetic case, while the entanglement of spins （1/2, 1） in the ferromagnetic case and the entanglement of spins （1/2, 1/2） in both ferromagnetic and antiferromagnetic cases almost decay exponentially to zero with increasing temperature. The critical point in the en-tanglement of spins （1/2, 1） in the antiferromagnetic case may be a signature of the quantum phase transition at finite temperature.

关键词： quantum entanglement quantum phase transition negativity

Effects of bioenergy production on environmental sustainability:a preliminary study based on expert opinions in Italy and Turkey

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Journal of Forestry Research 2018年第6期29卷 1611-1626页

作者： Tugba deniz Alessandro Paletto Department of Forest Economics Faculty of ForestryIstanbul University34473 BahcekoyIstanbulTurkey Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria-Research Centre for Forestry and Wood(CREA) Piazza Nicolini638123 TrentoItaly

In future decades, initiatives on biomass-based energy development in Europe should reduce fossil fuel dependence and help to combat climate change as required by the conference of the parties 21. In this context, forest biomass can play a key role within the bioenergy sector due to its high growth potential. The use of forest biomass for energy has positive and negative effects on other ecosystem services, on stand characteristics, and on forest management practices. The aim of this study is to analyse the effects of forest bioenergy production on six ecosystem services(biodiversity, recreation, landscape aesthetics,carbon sequestration, soil erosion protection, water quality). These effects have been assessed by 80 experts in two countries(Italy and Turkey), considering two different forest management practices(clear-cutting of coppices and woody residue removal after felling in high forests). The results show that coppice clear-cutting has negative effects on almost all ecosystem services according to the experts’ opinions. The highest negative effects are on landscape aesthetics and soil protection. The effects of woody residue removal on biodiversity, carbon sequestration, soil erosion protection, and water quality are considered negative by the experts, while the effects on recreation activities and landscape aesthetics are considered positive. The highest negative effects of this forest management scenario are on soil protection and biodiversity. The experts’ opinions about the effects of forest management practices on ecosystem services can provide information to understand the environmental sustainability of bioenergy development in future years.

关键词： Forest biomass Bioenergy Forest management Ecosystem services

Hepatic vein in living donor liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 318-323页

作者： deniz Balci Elvan Onur Kirimker Ankara University School of Medicine Department of SurgeryAnkara Universitesi Tip Fakultesi Ibni Sina Hastanesi Akademik Yerleske K-4 SıhhiyeAnkaraTurkey

Right lobe living donor liver transplantation(LDLT)is a major development in adult LDLT that has significantly increased the donor pool by providing larger graft size and by decreasing risk of small-for-size graft ***,right lobe anatomy is complex,not only from the inflow but also from the outflow *** reconstruction is one of the key requirements of a successful LDLT and venous drainage of the liver graft is just as important as hepatic inflow for the integrity of graft *** complications may cause acute graft failure which is not always easy to *** right lobe graft consists of two sections and three hepatic venous routes for drainage that require *** order to obtain a congestion free graft,several types of vascular conduits and postoperative interventions are needed to assure an adequate venous allograft *** review described the anatomy,functional basis and the evolution of outflow reconstruction in right lobe LDLT.

关键词： Living donor liver transplantation Hepatic vein Vascular graft

Nonnegative non-redundant tensor decomposition

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Frontiers of Mathematics in China 2013年第1期8卷 41-61页

作者： Olexiy KyRGyZOV deniz ERDOGMUS Laboratoire d'Outils pour l'Analyse de Donn@es LIST CEA Gif-sur-Yvette F-91911 France Cognitive Systems Lab Department of Electrical and Computer Engineering Northeastern University Boston MA 02115 USA

Nonnegative tensor decomposition allows us to analyze data in their ＇native＇ form and to present results in the form of the sum of rank-1 tensors that does not nullify any parts of the factors. In this paper, we propose the geometrical structure of a basis vector frame for sum-of-rank-1 type decomposition of real-valued nonnegative tensors. The decomposition we propose reinterprets the orthogonality property of the singularvectors of matrices as a geometric constraint on the rank-1 matrix bases which leads to a geometrically constrained singularvector frame. Relaxing the orthogonality requirement, we developed a set of structured-bases that can be utilized to decompose any tensor into a similar constrained sum-of-rank-1 decomposition. The proposed approach is essentially a reparametrization and gives us an upper bound of the rank for tensors. At first, we describe the general case of tensor decomposition and then extend it to its nonnegative form. At the end of this paper, we show numerical results which conform to the proposed tensor model and utilize it for nonnegative data decomposition.

关键词： matrix tensor rank-1 decomposition basis vector frame

Investigating different methods used for approximating pillar loads in longwall coal mines

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International Journal of Mining Science and Technology 2021年第1期31卷 23-32页

作者： deniz Tuncay a Ihsan Berk Tulu a Ted Klemetti Department of Mining Engineering West Virginia UniversityMorgantown 26501USA NIOSH Pittsburgh Mining Research Division Pittsburgh 15236USA

Accurately estimating load distributions and ground responses around underground openings play a significant role in the safety of the operations in underground *** designing pillars and other support measures relies highly on the accurate assessment of the loads that will be carried by them,as well as the load-bearing capacities of the *** are various methods that can be used to approximate mining-induced loads in stratified rock masses to be used in pillar *** empirical methods are based on equations derived from large databases of various case *** are implemented in government approved design tools and are widely *** are also analytical and numerical techniques used for more detailed analysis of the induced *** this study,two different longwall mines with different panel width-to-depth ratios are analyzed using different *** empirical method used in the analysis is the square-decay stress function that uses the abutment angle concept,implemented in pillar design software developed by the National Institute for Occupational Safety and Health(NIOSH).The first numerical method used in the analysis is a displacement-discontinuity(DD)variation of the boundary element method,LaModel,which utilizes the laminated overburden *** second numerical method used in the analysis is Fast Lagrangian Analysis of Continua(FLAC)with the numerical modeling approach recently developed at West Virginia University which is based on the approach developed by *** model includes the 2D slice of a cross-section along the width of the panel with the chain pillar system that also includes the different stratigraphic layers of the *** three methods gave similar results for the shallow mine,both in terms of load percentages and distribution where the variation was more obvious for the deep cover *** FLAC3D model was observed to better capture the stress changes observed during the field measurements for both

关键词： Abutment loads Numerical modeling LaModel FLAC3D Longwall coal mines

Analysis of ARMPS2010 database with LaModel and an updated abutment angle equation

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International Journal of Mining Science and Technology 2020年第1期30卷 111-118页

作者： deniz Tuncay Ihsan Berk Tulu Ted Klemetti Department of Mining Engineering West Virginia UniversityMorgantownWV 26505USA National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

The Analysis of retreat Mining Pillar Stability(ARMPS) program was developed by the National Institute for Occupational Safety and Health(NIOSH) to help the United States coal mining industry to design safe retreat room-and-pillar panels. ARMPS calculates the magnitude of the in-situ and mining-induced loads by using geometrical computations and empirical rules. In particular, the program uses the "abutment angle" concept in calculating the magnitude of the abutment load on pillars adjacent to a gob. In this paper, stress measurements from United States and Australian mines with different overburden geologies with varying hard rock percentages were back analyzed. The results of the analyses indicated that for depths less than 200 m, the ARMPS empirical derivation of a 21° abutment angle was supported by the case histories;however, at depths greater than 200 m, the abutment angle was found to be significantly less than 21°. In this paper, a new equation employing the panel width to overburden depth ratio is constructed for the calculation of accurate abutment angles for deeper mining cases. The new abutment angle equation was tested using both ARMPS2010 and La Model for the entire case history database of ARMPS2010. The new abutment angle equation to estimate the magnitude of the mining-induced loads used together with the La Model program was found to give good classification accuracies compared to ARMPS2010 for deep cover cases.

关键词： Abutment angle ARMPS2010 LaModel ARMPS-LAM Coal mining Pillar stability

Quantum Chemical Calculations of Warfarin Sodium,Warfarin and Its Metabolites

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Communications in Computational Physics 2008年第6期4卷 161-176页

作者： Emine deniz(Calısır)Tekin Figen Erkoc Ilkay yıldız Sakir Erkoc Department of Physics Middle East Technical University06531 AnkaraTurkey Department of Biology Education Gazi University06500 AnkaraTurkey Department of Pharmaceutical Chemistry Faculty of PharmacyAnkara University06100 AnkaraTurkey

The structural,vibrational and electronic properties of warfarin sodium,warfarin and its metabolites have been investigated theoretically by performing the molecular mechanics(MM+force field),the semi-empirical self-consistent-field molecular-orbital(AM1),and density functional theory *** geometry of the molecules have been optimized,the vibrational dynamics and the electronic properties of the molecules have been calculated in their ground state in gas phase.

关键词： Warfarin semi-empirical method ab initio calculation density functional method.