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Chinese Physics B 2019年第6期28卷 324-331页

作者： M kurt H Yurtseven A kurt S Aksoy Department of Physics Canakkale 18 Mart University17100 CanakkaleTurkey Department of Physics Middle East Technical University06531 AnkaraTurkey Lapseki iCDAS CiB MTAL High School 17100 CanakkaleTurkey

The ρ(NH2) infrared(iR) frequencies and the corresponding full width at half maximum(FWHM) values for(CH3)2 NH2 FeⅢ M Ⅱ(HCOO)6(DMFe M, M = Ni, Zn, Cu, Fe, and Mg) are analyzed at various temperatures by using the experimental data from the literature. For the analysis of the iR frequencies of the ρ(NH2) mode which is associated with the structural phase transitions in those metal structures, the temperature dependence of the mode frequency is assumed as an order parameter and the iR frequencies are calculated by using the molecular field theory. Also, the temperature dependence of the iR frequencies and of the damping constant as calculated from the models of pseudospin(dynamic disorder of dimethylammonium(DMA+) cations)–phonon coupling(PS) and of the energy fluctuation(EF), is fitted to the observed data for the wavenumber and FWHM of the ρ(NH2) iR mode of the niccolites studied here. We find that the observed behavior of the iR frequencies and the FWHM of this mode can be described adequately by the models studied for the crystalline structures of interest. This method of calculating the frequencies(iR and Raman) and FWHM of modes which are responsible for the phase transitions can also be applied to some other metal organic frameworks.

关键词： infrared(iR) frequency full width at half maximum(FWHM) phase transitions ρ(NH2) mode niccolites

New Analytical and Numerical Results For Fractional Bogoyavlensky-Konopelchenko Equation Arising in Fluid Dynamics

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Applied Mathematics(A Journal of Chinese Universities) 2020年第1期35卷 101-112页

作者： Ali kurt Department of Mathematics Pamukkale UniversityDenizli 20180Turkey

in this article,(2+1)-dimensional time fractional Bogoyavlensky-Konopelchenko(BK)equation is studied,which describes the interaction of wave propagating along the x axis and y *** acquire the exact solutions of BK equation we employed sub equation method that is predicated on Riccati equation,and for numerical solutions the residual power series method is *** graphical results that compares the numerical and analytical solutions are given for di erent values of.Also comparative table for the obtained solutions is presented.

关键词： Conformable Fractional Derivative Fractional Bogoyavlensky-Konopelchenko Equation Sub-Equation Method Residual Power Series Method

Exploration of the Townsend regime by discharge light emission in a gas discharge device

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Chinese Physics B 2014年第1期23卷 289-296页

作者： Hilal Yucel kurt Gazi University Faculty of Sciences Department of Physics 06500 Ankara Turkey

The Townsend discharge mechanism has been explored in a planar microelectronic gas discharge device （MGDD） with different applied voltages U and interelectrode distance d under various pressures in air. The anode and the cathode of the MGDD are formed by a transparent SnO2 covered glass and a GaAs semiconductor, respectively. in the experiments, the discharge is found to be unstable just below the breakdown voltage Ub, whereas the discharge passes through a homo- geneous stable Townsend mode beyond the breakdown voltage. The measurements are made by an electrical circuit and a CCD camera by recording the currents and light emission （LE） intensities. The intensity profiles, which are converted from the 3D light emission images along the semiconductor diameter, have been analysed for different system parameters. Dif- ferent instantaneous conductivity ~t regimes are found below and beyond the Townsend region. These regimes govern the current and spatio-temporal LE stabilities in the plasma system. it has been proven that the stable LE region increases up to 550 Torr as a function of pressure for small d. if the active area of the semiconductor becomes larger and the interlectrode distance d becomes smaller, the stable LE region stays nearly constant with pressure.

关键词： Townsend discharge breakdown microelectronic gas discharge device semiconductor cathode

Effect of ZrSiO_4 on the Friction Performance of Automotive Brake Friction Materials

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Journal of Materials Science & Technology 2007年第6期23卷 843-850页

作者： Mustafa BOZ Adem kurt Metallurgy Department Z.K.U.Karabük Technical Education Faculty78200 KarabükTurkey Metallurgy Department Gazi UniversityTechnical Education Faculty06500 AnkaraTurkey

Friction-wear properties of the ZrSiO4 reinforced samples were measured and compared with those of plain bronze based ones. For this purpose, density, hardness, friction coefficient wear behaviour of the samples were tested. Microstructures of samples before and after sintering and worn surfaces were also investigated by scanning electron microscopy （SEM）, and the wear types were determined. The optimum friction-wear behaviour was obtained in the sample compacted at 500 MPa and sintered at 820℃. Density of the final samples decreased with increasing the amount of reinforcing elements （ZrSiO4） before pre-sintering. However after sintering, there is no change in density of the samples including reinforcing elements （ZrSiO4）. With increasing friction surface temperature, a reduction in the friction coefficient of the samples was observed. However, the highest reductions in the friction coefficients were observed in the as-received samples containing 0. 5% reinforced ZrSiO4. The SEM images of the sample indicated that while bronze-based break lining material without ZrSiO4 showed abrasive wear behaviour, increasing the amount of ZrSiO4 resulted a change in abrasive to adhesive wear mechanism. All samples exhibited friction-wear values, which were within the values shown in SAE-J661 standard. With increasing the amount of reinforcing ZrSiO4, wear resistance of the samples was increased. However samples reinforced with 5% and 6% ZrSiO4 showed the best results.

关键词： Friction materials ZrSiO4 Wear Friction Brake lining

Effect of Different Amounts of Graphite on the Sintering and Transverse Rupture Properties of Powder Metal Parts

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Journal of Materials Science & Technology 2006年第3期22卷 419-422页

作者： Mustafa Boz Adem kurt Karabuk Technical Education Faculty Zonguldak Karaelmas University Karabuk 78050 Turkey Technical Education Faculty Gazi University Besevler 06500 Ankara Turkey

iron powders were mixed with graphite powders by 1-15 wt pct to produce block samples using powder metallurgy technique. The powders were blended in a three dimensional blender for 20 min and compacted in a die under 500 MPa by using a one directional press. Sinterability and mechanical properties of the samples with different carbon content were investigated. Sintering process was carried out on a belt furnace with flame curtain in dissociated ammonia atmosphere. Block samples produced were suitable for ASTM B-312 transverse rupture strength test apparatus and were tested with 0.050 kN/s velocity in a press under 100 g load. it was found that graphite amount up to 2 wt pct increased the contact area of particles and acted as a lubricant to affect the sintering behaviour positively. The results indicated that the samples containing up to 5 wt pct showed good sintering behaviour and also good hardness due to an increase in pearlite amount. However, the samples containing higher amount of graphite （more than 5 wt pct） affected the sintering behaviour negatively due to the settlement of free graphite around the Fe powders, which resulted in a decrease in the hardness and transverse rupture strength.

关键词： Powder metallurgy Sintering Fe Graphite Transverse rupture strength

interfacial Microstructure of Diffusion Bonded inconel 738 and Ferritic Stainless Steel Couple

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Journal of Materials Science & Technology 2009年第4期25卷 527-530页

作者： Bulent kurt Mustafa Ulutan Bartin University Faculty of EngineeringDept.of Metallurgical and Materials Engineering University of Eskisehir Osmangazi Faculty of EngineeringDept. of Mech.Eng

in this study, inconel 738 alloy was diffusion bonded to a ferritic stainless steel. The effect of bonding temperature on the microstructural development across the joint region was investigated. Following the diffusion bonding, conventional characterization techniques such as scanning electron microscopy （SEM）, energy dispersive X-ray （EDX） and microhardness were used to examine the interracial microstructure. it was seen that bonding temperature was effective on the diffusion of Ni from inconel 738 to ferritic stainless steel that affected the microstructure of the interface. Austenite phase was formed at the interface as a result of Ni diffusion from the inconel 738 to the interface.

关键词： Diffusion bonding inconel 738 Ferritic stainless steel interface

Effects of magnet shapes on total harmonic distortion and cogging torque in a permanent magnet synchronous generator for wind turbines

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Clean Energy 2023年第5期7卷 1058-1068页

作者： Erol kurt Adem Dalcalı Gazi University Department of Electrical and Electronics EngineeringTechnology FacultyAnkaraTurkey Bandırma Onyedi Eylul University Department of Electrical and Electronics EngineeringFaculty of Engineering and Natural SciencesBandırmaBalıkesirTurkey National Research University TIIAME100000TashkentUzbekistan

This paper explores and theoretically reports the effects of different magnet structures on the cogging torque and the total harmonic distortion of the output waveforms from a permanent magnet *** generator is a radial flux machine and four different structures are considered for the magnet arrangement in the rotor component and modelled in the Ansys/Maxwell electromagnetic simulation *** three-phase machine exhibits different behaviours towards various magnet structures,***,inclined slotted rectangular,skewed double rectangular and inclined slotted skewed double rectangular,*** has been proven by finite element analysis and Fourier analysis that both the cogging and total harmonic distortion values vary significantly for all *** cogging torque values change in the range of 89.95 to 436.75 mNm and the lowest cogging torque is measured for the inclined slotted skewed double rectangular magnet geometry,while the conventional rectangular magnet geometry yields the worst value with 436.75 ***,the total harmonic distortion values varies between 1.63 and 3.55 for different magnetic *** the worst total harmonic distortion value is obtained from the inclined slotted rectangular magnet,the best total harmonic distortion is acquired from the skewed double rectangular *** these results will provide scientists and engineers with important information in order to obtain more efficient machines.

关键词： renewable energy wind power finite element method synchronous generator wind turbines

interaction of Mantle Rocks with Crustal Fluids: Sagvandites of the Scandinavian Caledonides

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Journal of Earth Science 2019年第6期30卷 1084-1094页

作者： kurt Bucher ingrid Stober Mineralogy and Petrology Institute of Earth and Environmental SciencesUniversity of Freiburg79104 FreiburgGermany College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266510China

Sagvandite is an enstatite+magnesite rock formed from dunite or harzburgite bodies occurring as tectonically emplaced fragments from the upper mantle in many orogenic belts by interaction with CO2-bearing crustal fluids at upper amphibolite facies P-T *** bodies occur widespread in distinct nappes in the Scandinavian Caledonides in *** to all of the many sagvandite outcrops is their general structure of radial bundles of very coarse cm-sized enstatite crystals and interstitial *** some strongly resorbed primary olivine is preserved,in addition to minor accessory Cr-spinel and *** dunite to sagvandite conversion is governed by three metasomatic reactions:(1)carbonatization of peridotite by CO2-bearing fluids;(2)interaction with external fluids containing dissolved silica;(3)loss of Mg by dissolution of forsterite in NaCl-rich deep *** progressξoverall of all three reactions in proportions that conserve the volume of the original dunite can explain the observed structure and mode of *** relationship among the progressξof the three reactions suggests that loss of Mg by the ultramafic rock is the dominating process in the iso-volume conversion of dunite to sagvandite.

关键词： sagvandite peridotite fluid-rock interaction metasomatism CO2-sequestration

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The plant cell wall

Journal of integrative Plant Biology 2015年第4期57卷 328-329页

作者： kurt Fagerstedt Anna Karkonen Department of Biosciences Division of Plant Biology University of Helsinki Department of Agricultural Sciences University of Helsinki

Research on the many aspects of the plant cell wall has experienced reiuvenation during the past few years. This is perhaps mainly due to the commercial interest in the chemical components of the cell wall that have potential for industrial use＂ Cellulose for fibers and together with hemicelluloses for bioethanol, lignin for plastics or biofuel, pectins as gel agents, let alone woody cell wall material for construction or pulp production and for intelligent materials for electronics - the new uses are mindboggling!

关键词： cell As The plant cell wall

Voltage gated calcium channel antibody-related neurological diseases

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World Journal of Clinical Cases 2015年第3期3卷 293-300页

作者： Can Ebru Bekircan-kurt Eda DerleÇiftçi Aslι Tuncer Kurne Banu Anlar Neurology Department Faculty of Medicine Hacettepe University Neurology Department Faculty of MedicineBaşkent University06490 AnkaraTurkey Pediatric Neurology Department Faculty of Medicine Hacettepe University

Voltage gated calcium channel(VGCC) antibodies are generally associated with Lambert-Eaton myasthenic syndrome. However the presence of this antibody has been associated with paraneoplastic as well as nonparaneoplastic cerebellar degeneration. Most patients with VGCC-antibody-positivity have small cell lung cancer(SCLC). Lambert-Eaton myasthenic syndrome(LEMS)is an autoimmune disease of the presynaptic part of the neuromuscular junction. its classical clinical triadis proximal muscle weakness, areflexia and autonomic dysfunction. Fifty to sixty percent of LEMS patients have a neoplasia, usually SCLC. The co-occurrence of SCLC and LEMS causes more severe and progressive disease and shorter survival than non-paraneoplastic LEMS. Treatment includes 3,4 diaminopyridine for symptomatic purposes and immunotherapy with prednisolone, azathioprine or intravenous immunoglobulin in patients unresponsive to 3,4 diaminopyridine. Paraneoplastic cerebellar degeneration(PCD) is a syndrome characterized with severe, subacute pancerebellar dysfunction. Serum is positive for VGCC antibody in 41%-44% of patients, usually with the co-occurrence of SCLC. Clinical and electrophysiological features of LEMS are also present in 20%-40% of these patients. Unfortunately, PCD symptoms do not improve with immunotherapy. The role of VGCC antibody in the immunopathogenesis of LEMS is well known whereas its role in PCD is still unclear. All patients presenting with LEMS or PCD must be investigated for SCLC.

关键词： Voltage gated calcium channel antibody Lambert-Eaton myasthenic syndrome Paraneoplastic cerebellar degeneration Onconeural antibodies Small cell lung cancer