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A reconstruction of Turkey’s potential natural vegetation using climate indicators

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Journal of Forestry Research 2019年第6期30卷 2199-2211页

作者： Nussa bah B.Raja Olgu aydin Ihsan cicek Necla Turkoglu GeoZentrum Nordbayern University Erlangen-Numberg91054 ErlangenGermany Department of Geography Faculty of HumanitiesAnkara University06100 AnkaraTurkey

Turkey,containing three of the world’s biodiversity hotspots,is a hub for genetic ***,the vegetation cover has drastically changed in recent decades as a result of substantial transformations in landuse practices.A map of the potential natural vegetation can be used to represent the biodiversity of a country,and therefore a reference to effectively develop conservation *** multinomial logistic regression is used to simulate the probability of different biomes occurring in the country using elevation,climatological data and natural vegetation data.A correlation test was applied to the climatological data to determine which predictors influence vegetation the *** were temperature,precipitation,relative humidity and *** Ordinary Kriging method was employed to transform the data into the format for the multinomial logistic regression *** model showed that temperature was the most influencing factor with respect to Turkey’s vegetation and distribution follows a similar distribution as the various *** forests are mostly found in the Black Sea region,which is also the wettest region of the *** Marmara region is the only other region where there are broadleaf *** forests and shrublands are mostly located in Central Anatolia due to the region’s low humidity which favours herbaceous *** forests were dominant in the Aegean and Mediterranean regions,attributed to high temperatures.

关键词： Biomes Multinomial logistic regression Statistical modelling Turkey Vegetation

Acoustic beam splitting in a sonic crystal around a directional band gap

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Chinese Physics B 2013年第11期22卷 350-355页

作者： Ahmet cicek Olgun Adem Kaya Bulent Ulug Department of Physics Faculty of Arts and Sciences Mehmet Akif Ersoy University Department of Computer Education and Educational Technology Faculty of Education Inonu University 44280 Department of Physics Faculty of Science Akdeniz University

Beam splitting upon refraction in a triangular sonic crystal composed of aluminum cylinders in air is experimentally and numerically demonstrated to occur due to finite source size, which facilitates circumvention of a directional band gap. Experiments reveal that two distinct beams emerge at crystal output, in agreement with the numerical results obtained through the finite-element method. Beam splitting occurs at sufficiently-small source sizes comparable to lattice periodicity determined by the spatial gap width in reciprocal space. Split beams propagate in equal amplitude, whereas beam splitting is destructed for oblique incidence above a critical incidence angle.

关键词： sonic crystal directional band gap source size beam splitting

Performance of recycling abrasives in rock cutting by abrasive water jet

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Journal of Central South University 2015年第3期22卷 1055-1061页

作者： Gokhan aydin Karadeniz Technical University Department of Mining Engineering

Rock cutting performance of recycling abrasives was investigated in terms of cutting depth, kerf width, kerf taper angle and surface roughness. Gravity separation technique was employed to separate the abrasives and the rock particles. The recycling abrasive particles were then dried and sieved for determination of their disintegration behaviors. Before each cutting with recycling abrasives, the abrasive particles less than 106 ?m were screened out. It is revealed that a considerable amount of used abrasives can be effectively reused in the rock cutting. The reusabilities of abrasives are determined as 81.77%, 57.50%, 34.37% and 17.72% after the first, second, third and fourth cuttings, respectively. Additionally, it is determined that recycling must be restricted three times due to the excessive disintegration of abrasives with further recycling. Moreover, it is concluded that cutting depth, kerf width and surface roughness decreases with recycling. No clear trend is found between the kerf taper angle and recycling. Particle size distribution is determined as an important parameter for improving the cutting performance of recycling abrasives.

关键词： abrasive water jet rock abrasive recycling

Effect of solid waste materials on properties of magnesium matrix composites-A systematic review

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Journal of Magnesium and Alloys 2022年第10期10卷 2673-2698页

作者： Fatih aydin TOBB Technical Sciences Vocational School Karabuk UniversityTurkey

The need for light and high specific strength materials in many fields such as automotive and aerospace is increasing day by ***(Mg)-based materials have become attractive for many industries thanks to their high specific strength, good vibration damping ability, and recyclability. However, Mg’s low strength and wear resistance are important barriers limiting its industrial use. Researchers are developing Mg matrix composites using various reinforcements and expanding the use of Mg-based materials. The conventional reinforcements are Al2O3, SiC, B4C, TiB2, CNT, and GNPs for the production of Mg matrix composites. Researchers have been trying to reduce the cost of Mg matrix composites in recent years by using cheaper and environmentally friendly reinforcements. These reinforcements are solid wastes such as eggshell, fly ash, red mud, and waste glass, and their use in composite systems is becoming more common day by day. This review focuses on the Mg matrix composites reinforced with solid waste particles and the changes in wear, mechanical, corrosion, and thermal properties with the addition of these reinforcements.

关键词： Mg matrix composites Solid waste reinforcements Wear Corrosion Mechanical properties

Optical, Energetic and Exergetic Analyses of Parabolic Trough Collectors

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Chinese Physics Letters 2007年第7期24卷 1787-1790页

作者： OZTURK Murat, cicek BEZiR Nalan OZEK Nuri Department of Physics Science-Literature Faculty Siileyman Demirel University Isparta TUrkey

Parabolic trough collectors generate thermal energy from solar energy. Especially, they are very convenient for applications in high temperature solar power systems. To determine the design parameters, parabolic trough collectors must be analysed with optical analysis. In addition, thermodynamics （energy and exergy） analysis in the development of an energy efficient system must be achieved. Solar radiation passes through Earth＇s atmosphere until it reaches on Earth＇s surface and is focused from the parabolic trough collector to the tube receiver with a transparent insulated envelope. A11 of them constitute a complex mechanism. We investigate the geometry of parabolic trough reflector and characteristics of solar radiation to the reflecting surface through Earth＇s atmosphere, and calculate the collecting totM energy in the receiver. The parabolic trough collector, of which design parameters are given, is analysed in regard to the energy and exergy analysis considering the meteorological specification in May, June, July and August in 1sparta/TUrkey, and the results are presented.

关键词： Exergetic Parabolic Collectors

Biofilter:a promising tool for mitigating methane emission from manure storage

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Journal of Arid Land 2011年第1期3卷 61-70页

作者： Nazim cicek Danny MANN Department of Biosystems Engineering University of Manitoba

Liquid manure storage may contribute to methane （CH4） emission and this emission can be greatly reduced if appropriate management practices are applied. Biofiltration has been used in other fields for mitigating greenhouse gas （GHG） emission （e.g., landfill） and shown promise for mitigation OH4 emis- sion from liquid manure storage. It has been reported that biofilter was capable of reducing 80% of CH4 emissions from manure storage. The OH4 removal efficiency is influenced by many factors, including OH4 and 02 concentrations, temperature, moisture, composition of the filter bed, nutrient, and empty bed resi- dency time （EBRT）. Biological conversion of methane of a biofilter is a slow process due to the low water solubility of methane. The residence times （EBRT） between 5 min and 5 h have been used, whereas a typical EBRT of 25 s is used for common biofilter applications. Temperature at which methanotrophic bac- teria are active ranges from 10℃ to 45℃. The maximum activity is found at around 30℃. The optimal filter bed water content depends on both the gas flow rate and the type of filter bed （soil, compost, etc.） and ranges from 30%-70% of the water holding capacity. Compost is the best material for filter bed. The optimal pH for methanotrophic bacteria is neutral to slightly acidic. Copper and nitrogen compounds especially nitrate are important nutrients to methanotrophic bacteria but their optimal concentrations have not been founded. Phosphorus and other elements such as potassium and manganese are reported to affect the performance of methanotrophic bacteria but need further confirmation.

关键词： biofilter greenhouse gas methane manure storage

Evaluation of a developed bypass viscous damper performance

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 773-791页

作者： Mahrad FAHIMINIA aydin SHISHEGARAN Structural Engineering Islamic Azad UniversityTehranIran Structural Engineering School of Civil EngineeringIran University of Science and TechnologyTehranIran

In this study,the dynamic behavior of a developed bypass viscous damper is *** viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner ***,the viscosity coficient of the damper can be adjusted using geometrical dimensions of the ***,the external orifice acts as a thermal compensator and alleviates viscous heating of the *** to experimental results,Computational Fluid Dynamic(CFD)model,a numerical formula and the *** model are found and assessed;therefore,the verification of numerical and computational models are evaluated for ***,a simplifed procedure is proposed to design structures with bypass viscous *** design procedure is applied to design an 8-story hospital structure with bypass viscous dampers,and it is compared with the same structure,which is designed with concentric braces and without *** time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural ***,seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.

关键词： developed viscous damper extermal orifice energy dissipation seismic behavior CFD model of viscous damper a simplifed model

A New Palladium Complex Containing the Mixture of Carbene and Phosphine Ligands: Synthesis, Crystal Structure and Spectral FT-IR, NMR and UV-Vis Researches

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Chinese Journal of Structural Chemistry 2019年第10期38卷 1664-1672,1609页

作者： aydin Aktas Inonu University Faculty of Science Department of Chemistry

In this paper,a new Pd-based complex that contains A^-heterocyclic carbene(NHC)and triphenylphosphine(PPh?)ligands was *** c/5-(NHC)PdBr2(PPh3)complex has been prepared by the substitution of 3?chloropyridine ligand in(NHC)PdBr2(3-chloropyridine)complex with *** complex has been characterized by using 1^H NMR,^31P{^1H}NMR,^13C{^1H}NMR,FTIR,UV-Vis spectroscopy and elemental analysis *** molecular and crystal structures of the cz5-(NHC)PdBr2(PPh3)complex were determined by singlecrystal X-ray diffraction method.

关键词： FTIR N-heterocyclic carbene NMR UV-VIS X-ray diffraction

Topology optimization and seismic collapse assessment of shape memory alloy(SMA)-braced frames:Effectiveness of Fe-based SMAs

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 281-301页

作者： aydin HASSANZADEH Saber MORADI Department of Civil Engineering Ryerson UniversityToronto M5B 2K3Canada

This paper presents a seismic topology optimization study of steel braced frames with shape memory alloy(SMA)*** SMA-braced frames(SMA-BFs)with either Fe-based SMA or NiTi braces are determined in a performance-based seismic design *** topology optimization is performed on 5-and 10-story SMA-BFs considering the placement,length,and cross-sectional area of SMA bracing ***,strength,and performance-based design constraints are considered in the *** seismic response and collapse safety of topologically optimal SMA-BFs are assessed according to the FEMA P695 methodology.A comparative study on the optimal SMA-BFs is also presented in terms of total relative cost,collapse capacity,and peak and residual story *** results demonstrate that Fe-based SMA-BFs exhibit higher collapse capacity and more uniform distribution of lateral displacement over the frame height while being more cost-effective than NiTi braced *** addition to a lower unit price compared to NiTi,Fe-based SMAs reduce SMA material *** frames with Fe-based SMA braces,the SMA usage is reduced by up to 80%.The results highlight the need for using SMAs with larger recoverable strains.

关键词： topology optimization shape memory alloy Fe-based SMA steel braced frames performance-based seismic design collapse assessment