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Journal of Cotton Research 2022年第3期5卷 217-227页

作者： wedegaertner kurt SHEKOOFA Avat PURDOM Sam WALTERS Kellie DUNCAN Lori RAPER Tyson B Department of Plant Sciences University of Tennessee2505 E.J.Chapman Dr.KnoxvilleTN 37996USA Department of Biosystems Engineering and Soil Science University of Tennessee2506 EJ Chapman DriveKnoxvilleTN 37996USA.

Background:Cotton(Gossypium hirsutum L.)is often grown in locations characterized by high atmospheric evaporative *** has been hypothesized that plants which resist hydraulic flow under this condition will limit water use and conserve soil ***,in a series of controlled environment experiments ten cotton cultivars were exposed to two different temperature and vapor pressure deficit(VPD)conditions(i.e.,38℃,>3 kPa and 32℃,1∼1.5 kPa)as well as a progressive soil ***,individual differences in shoot hydraulic conductance(K_(shoot))was measured using a hydraulic conductance flow meter(HCFM).Physiological parameters were reported included leaf area,dry leaf weight,stomatal conductance(g_(s)),and water use efficiency coefficient(WUE_(k)).Results:Differences were observed in K_(shoot) among cultivars under the 38℃,>3 kPa but not the 32℃,1∼1.5 kPa *** the 38℃,>3 kPa environment,correlations were found between K_(shoot),stomatal conductance(gs),VPD breakpoint,WUEk,total leaf area,dry leaf weight,fraction transpirable soil water(FTSW)threshold,and slope of TR decline after FTSW ***:Results show that the ability of some cotton cultivars to restrict water loss under high evaporative demand through early stomatal closure is associated with the cultivars’K_(shoot).The K_(shoot) is influential in the limitation of TR trait under high temperature and VPD.

关键词： Cotton FTSW threshold Shoot hydraulic conductance Temperature Transpiration rate VPD

Cotton stomatal closure under varying temperature and vapor pressure deficit, correlation with the hydraulic conductance trait

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Calculation of the infrared frequency and the damping constant (full width at half maximum) for metal organic frameworks

Journal of Cotton Research 2022年第3期

作者： wedegaertner kurt SHEKOOFA Avat PURDOM Sam WALTERS Kellie DUNCAN Lori RAPER Tyson B.

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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 hyucelkurt@*** []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

Spin texturing in a parabolically confined quantum wire with Rashba and Dresselhaus spin-orbit interactions

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Chinese Physics B 2014年第1期23卷 347-356页

作者： S. Sar?kurt sevil.sarikurt@deu.edu.tr Dokuz Eyll University Faculty of Science Physics Department T?naztepe Campus 35390 ?zmir Turkey

In this study, we investigate theoretically the effect of spin-orbit coupling on the energy level spectrum and spin texturing of a quantum wire with a parabolic confining potential subjected to the perpendicular magnetic field. Highly accurate numerical calculations have been carried out using a finite element method. Our results reveal that the interplay between the spin-orbit interaction and the effective magnetic field significantly modifies the band structure, producing additional subband extrema and energy gaps. Competing effects between external field and spin-orbit interactions introduce comp｜ex features in spin texturing owing to the couplings in energy subbands. We obtain that spatia~ modulation of the spin density along the wire width can be considerably modified by the spin-orbit coupling strength, magnetic field and charge carrier concentration.

关键词： spin—orbit coupling zeeman splitting quantum wire spin texture

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