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The relationship between microwear on human teeth and nutrition:Samples from ancient Anatolian societies

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Natural Science 2013年第4期5卷 449-455页

作者： Serpil Ozdemir Alper Yener Yavuz ayla sevim erol Department of Anthropology Faculty of Arts and SciencesMehmet Akif Ersoy UniversityBurdurTurkey Department of Anthropology Faculty of LettersAnkara UniversityAnkaraTurkey

The relationship between tooth of living species and nutrition is so important for anthropologic researches that, it is among the most considered issues in almost all the researches that have been made about these topics. Tooth, as being one of the most significant materials that give information about diet, environmental relationships and cultural structure, has been a constant research topic. It has been proved with the researches that, the food stuffs, which living species consumed, have a fundamental role on tooth wear. The recently recognized micro marks on occlusal are also evaluated carefully as well as the macro wears, which are defined as the apparent wears on tooth enamel. These micro marks have several characteristics about the ingredients, hardness, size and chewing force of the nutrients. In this regard, the tooth samples of Agora of Smyrna, Kyzikos, MinnetpInarI and Güllüdere skeletons that lived in Anatolia—also constituted the sample of this research—have been investigated and the diet of these societies has been examined depending upon the micro marks on the teeth of these societies’ people. Firstly, the diet of these societies has been investigated by examining micro tooth wears. Then, the relationship of these societies has been studied. By examining micro tooth wears of these societies, it has been discussed that whether the factors of age, sex, and facet are effective or not on micro wear marks. As a result of this study, it has been observed that societies that lived in different areas have different diets;and micro marks on teeth are significant indicators of living spaces, subsistence economies and life styles of the societies.

关键词： Microwear Macrowear Facet Age Sex

Reinforcing effects of polypropylene on energy absorption and fracturing of cement-based tailings backfill under impact loading

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 650-664页

作者： Jiajian Li Shuai Cao erol Yilmaz School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology BeijingBeijing 100083China Department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdogan UniversityFenerRize TR53100Turkey

Polypropylene(PP)fiber-reinforced cement-based tailings backfill(FRCTB)is a green compound material with superior crack resistance and has good prospects for application in underground ***,FRCTB exhibits susceptibility to dynamic events,such as impact ground pressure and blast *** paper investigates the energy and crack distribution behavior of FRCTB under dynamic impact,considering the height/diameter(H/D)*** Hopkinson pressure bar,industrial computed tomography scan,and scanning electron microscopy(SEM)experiments were carried out on six types of *** outcomes confirmed fiber aggregation at the bottom of *** H/D was less than 0.8,the proportion of PP fibers distributed along theθangle direction of80°-90°*** the total energy,all samples presented similar energy absorption,reflectance,and ***,a rise in H/D may cause a rise in the energy absorption rate of FRCTB during the peak phase.A positive correlation existed between the average strain rate and absorbed energy per unit *** increase in H/D resulted in a decreased crack volume fraction of *** the H/D was greater than or equal to 0.7,the maximum crack volume fraction of FRCTB was observed close to the incidence *** cracks were present only in the FRCTB with an H/D ratio of *** with H/D ratios of 0.5 and 0.6 showed similar distributions of weakly and heavily damaged *** fibers can limit the emergence and expansion of cracks by influencing their *** observations revealed considerable differences in the bonding strengths between fibers and the *** that adhered particularly well to the substrate were attracted together with the hydration products adhering to *** results show that FRCTB is promising as a sustainable and green backfill for determining the design properties of mining with backfill.

关键词： cement-based tailings fiber-reinforced backfills fracture energy absorption impact loading

Continuous flow pyrolysis of virgin and waste polyolefins:a comparative study,process optimization and product characterization

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 133-149页

作者： Ecrin Ekici Güray Yildiz Magdalena Joka Yildiz Monika Kalinowska erolŞeker Jiawei Wang Karlsruhe Institute of Technology Institute of Catalysis Research and TechnologyEggenstein-Leopoldshafen 76344Germany Izmir Institute of Technology Faculty of EngineeringDepartment of Energy Systems EngineeringIzmir 35430Türkiye Department of Materials Engineering and Production Faculty of Mechanical EngineeringBialystok University of TechnologyBialystok 15-351Poland Department of Agricultural and Food Engineering and Environmental Development Institute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of Technology15-351 BialystokPoland Department of Chemistry Biology and BiotechnologyInstitute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of TechnologyBialystok 15-351Poland Izmir Institute of Technology Faculty of EngineeringDepartment of Chemical EngineeringIzmir 35430Türkiye Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirmingham B47ETUnited Kingdom

Under optimal process conditions,pyrolysis of polyolefins can yield ca.90 wt%of liquid product,i.e.,combination of light oil fraction and heavier *** this work,the experimental findings reported in a selected group of publications concerning the non-catalytic pyrolysis of polyolefins were collected,reviewed,and compared with the ones obtained in a continuously operated bench-scale pyrolysis *** process parameters were used for the pyrolysis of waste and virgin counterparts of high-density polyethylene,low-density polyethylene,polypropylene and a defined mixture of those(i.e.,25:25:50 wt%,respectively).To mitigate temperature drops and enhance heat transfer,an increased feed intake is employed to create a hot melt plastic *** 1.5 g·min^(-1) feed intake,1.1 L·min^(-1) nitrogen flow rate,and a moderate pyrolysis temperature of 450℃,the formation of light hydrocarbons was favored,while wax formation was limited for polypropylene-rich *** of virgin plastics yielded more liquid(maximum 73.3 wt%)than that of waste plastics(maximum 66 wt%).Blending polyethylenes with polypropylene favored the production of liquids and increased the formation of gasoline-range *** products were mainly composed of C3 hydrocarbons,and no hydrogen production was detected due to moderate pyrolysis temperature.

关键词： waste plastics polyolefins chemical recycling pyrolysis alternative fuels waste-to-energy

基于离散元-有限差分耦合的轨枕垫对有砟道床横向阻力的影响机制

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中南大学学报（自然科学版） 2024年第2期55卷 457-472页

作者：谭攀肖源杰姜钰王萌王小明张冲冲 TUTUMLUER erol 中南大学土木工程学院湖南长沙410075 重载铁路工程结构教育部重点实验室(中南大学) 湖南长沙410075 伊利诺伊大学香槟分校香槟61801美国

轨枕垫(USP)因其良好的减震性能已广泛应用于铁路轨道结构,现有研究大多集中于USP对轨道结构刚度和振动响应的影响,但对有砟道床横向阻力影响的研究很少。为深入分析USP对道床横向阻力的影响并揭示其作用机理,建立轨枕-USP-有砟道床-路... 详细信息

轨枕垫(USP)因其良好的减震性能已广泛应用于铁路轨道结构,现有研究大多集中于USP对轨道结构刚度和振动响应的影响,但对有砟道床横向阻力影响的研究很少。为深入分析USP对道床横向阻力的影响并揭示其作用机理,建立轨枕-USP-有砟道床-路基三维系统的精细化离散元-有限差分(DEM-FDM)耦合数值模型,采用典型重载铁路有砟道床横向阻力现场实测结果对模型进行标定和验证,进而模拟分析不同工况组合下USP对轨枕不同位置处(枕底、枕侧和枕端)的横向阻力、道砟颗粒运动和粒间接触力等宏微观指标的影响机制。研究结果表明:在相同的轨枕横向位移下,相较于无USP的轨枕,带USP的轨枕其枕底道砟颗粒运动范围更大,横向阻力也更大,且横向阻力增加部分主要来源于枕底USP的不平整性;USP刚度越大,道床横向阻力也越大;采用USP可增加枕底的横向剪应力和最大法向接触力,且两者数值均随USP刚度的增大而增大。

关键词：铁路轨道有砟道床道砟轨枕垫横向阻力离散元-有限差分耦合

Progress and prospects of mining with backfill in metal mines in China

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International Journal of Minerals,Metallurgy and Materials 2023年第8期30卷 1455-1473页

作者： Gaili Xue erol Yilmaz Yongding Wang College of Mining Technology Taiyuan University of TechnologyTaiyuan030024China Research Center of Green Mining Engineering Technology in Shanxi Province Taiyuan030024China Department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdogan UniversityFenerRizeTR53100Turkey Longshou Mine Jinchuan Group Co.Ltd.Jinchuan737100China

Mining is the foundation of modern industrial *** the context of the“carbon peaking and carbon neutrality”era,countries have put forward the development strategy of“adhering to the harmonious coexistence of humans and nature.”The ongoing progress and improvement of filling mining technology have provided significant advantages,such as“green mining,safe,efficient,and low-carbon emission,”which is crucial to the comprehensive utilization of mining solid waste,environmental protection,and safety of *** review paper describes the development history of metal mine filling mining in China and the characteristics of each *** excitation mechanism and current research status of producing cementitious materials from blast furnace slag and other industrial wastes are then presented,and the concept of developing cementitious materials for backfill based on the whole solid waste is *** advances in the mechanical characteristics of cemented backfill are elaborated on four typical levels:static mechanics,dynamic mechanics,mechanical influencing factors,and multi-scale *** working/rheological characteristics of the filling slurry are presented,given the importance of the filling materials conveying ***,the future perspectives of mining with backfill are discussed based on the features of modern filling concepts to provide the necessary theoretical research value for filling mining.

关键词： mining with backfill cementitious materials mechanical characteristics slurry properties future perspectives

Effect of layer thickness on the flexural property and microstructure of 3D-printed rhomboid polymer-reinforced cemented tailing composites

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 236-249页

作者： Ziyue Zhao Shuai Cao erol Yilmaz State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdoğan UniversityFenerRize TR53100Turkey

For mines with poor ore bodies and surrounding rocks,the general mining method does not allow the ore to be extracted from underground safely and *** these mines,the downward layered filling mining technique is undoubtedly the most suitable mining *** downward filling mining technique may eliminate the troubles relating to poor ore deposit conditions,such as production safety,ore loss rate,and depletion ***,in this technique,the safety of the artificial roof of the next stratum is of paramount *** tailings backfilling(CTB)that is not sufficiently cemented and causes collapses could threaten ore *** paper explores a diamond-shaped composite structure to mimic the stability of a glued false roof in an actual infill mine based on the recently emerged three-dimensional(3D)printing *** means such as three-point bending and digital image correlation(DIC)techniques were used to explore the flexural characteristics of 3D construction specimens and CTB combinations with different cement/tailings weight ratios at diverse layer *** results show that the 3D structure with a 14-mm ply height and CTB has strong flexural characteristics,with a maximum deflection value of 30.1 mm,while the 3D-printed rhomboid polymer(3D-PRP)structure with a 26-mm ply height is slightly worse in terms of flexural strength characteristics,but it has a higher maximum flexural strength of 2.83 MPa.A combination of 3D structure and CTB has more unique mechanical properties than CTB *** research work offers practical knowledge on the artificial roof performance of the downward layered filling mining technique and builds a scientific knowledge base regarding the successful application of CTB material in mines.

关键词： tailings cemented fills 3D printed rhomboidal polymer three-point bending test digital image correlation

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

Compressive fatigue behavior and failure evolution of additive fiber-reinforced cemented tailings composites

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 345-355页

作者： Jiajian Li Shuai Cao erol Yilmaz Yunpeng Liu School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology BeijingBeijing 100083China Department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdogan UniversityFenerRize TR53100Turkey State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology) Wuhan 430070China

The ordinary cemented tailings backfill(CTB)is a cement-based composite prepared from tailings,cementitious materials,and *** this study,a series of laboratory tests,including uniaxial compression,digital image correlation measurement,and scanning electron microscope characteristics of fiber-reinforced CTB(FRCTB),was conducted to obtain the uniaxial compressive strength(UCS),failure evolution,and microstructural characteristics of FRCTB *** results show that adding fibers could increase the UCS values of the CTB by 6.90%to 32.76%.The UCS value of the FRCTB increased with the increase in the polypropylene(PP)fiber ***,the reinforcement effect of PP fiber on the CTB was better than that of glass *** addition of fiber could increase the peak strain of the FRCTB by0.39%to 1.45%.The peak strain of the FRCTB increased with the increase in glass fiber *** failure pattern of the FRCTB was coupled with tensile and shear *** addition of fiber effectively inhibited the propagation of cracks,and the bridging effect of cracks by the fiber effectively improved the mechanical properties of the *** findings in this study can provide a basis for the backfilling design and optimization of mine backfilling methods.

关键词： cemented tailings backfill uniaxial compressive strength combined fiber reinforcement digital image correlation microstructural characteristics

Current diagnostic tools and treatment modalities for rectal prolapse

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World Journal of Clinical Cases 2023年第16期11卷 3680-3693页

作者： Mustafa Oruc Timucin erol Department of General Surgery Hacettepe University School of MedicineAnkara 06100Turkey

Rectal prolapse is a circumferential,full-thickness protrusion of the rectum through the *** is a rare condition,and only affects 0.5%of the general *** treatment modalities have been described,which have changed significantly over *** in the last decade,laparoscopic and robotic surgical approaches with different mobilization techniques,combined with medical therapies,have been widely *** patients have presented with a wide range of complaints(ranging from abdominal discomfort to incomplete bowel evacuation,mucus discharge,constipation,diarrhea,and fecal incontinence),understanding the extent of complaints and ruling out differential diagnoses are essential for choosing a tailored surgical *** is crucial to assess these additional symptoms and their severities using preoperative scoring ***,radiological and physiological evaluations may explain some vague symptoms and reveal concomitant pelvic ***,there is no consensus on or standardization of the optimal extent of dissection,type of procedure,and materials used for rectal fixation;this makes providing maximum benefits to patients with minimal complications *** recent publications and systematic reviews have not recommended the most appropriate treatment *** review explains the appropriate diagnostic tools for different conditions and summarizes the current treatment approaches based on existing literature and expert opinions.

关键词： Rectal prolapse Constipation Fecal incontinence Diagnosis Minimally invasive surgical procedures Colorectal surgery