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Acta Geologica sinica(English Edition) 2001年第1期75卷 59-65页

作者： sükrü koc Ali RECBER Geology Department Ankara UniversityAnkara 06100Turkey General Directorate of Mineral Research and Exploration Ankara

Fluorite mineralization occurs along fractures and cracks of Middle Eocene and Pliocene limestones and marls in the north and northeast of the P?hrenk region (?i?ekdagi, Kirsehir). Tb/Ca – Tb/La and Y/Ho ratios were obtained from REE contents of fluorites which have revealed that mineralization is of hydrothermal type. Negative Ce anomalies and positive Eu anomalies reflect that hydrothermal solutions once had high oxygen fugacity. Fluid inclusion studies indicate that homogenization temperatures of mineralization varied between 90°C and 200°C, and hydrothermal solutions are composed of NaCl + KCl + MgCl2 + H2O. In addition, salinity measurements show that hydrothermal solutions were mixed with meteoric or rock formation water. Geologic setting, REE geochemistry and fluid inclusion studies suggest that mineralization was deposited from a solution generated by mixing of magmatic and meteoric water under epithermal conditions.

关键词： fluorite rare earth elements fluid inclusions

Geochemistry of Kestelek Colemanite Deposit, Bursa, Turkey

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Journal of Earth science 2017年第1期28卷 63-77页

作者： sükrü koc Ozge Kavrazh ismail kocak Faculty of Department of Geological Engineering Ankara University Ankara 06100 Turkey Graduate school of Natural and Applied sciences Ankara University Ankara 06100 Turkey Department of Geological Engineering Bozok University Yozgat 66100 Turkey

The Kestelek borate deposit has been the subject of geological and mineralogical research over the last decades, but major and trace element geochemistry of this deposit was first investigated in the present study. A total of 22 samples collected from surface exposures and different depths of deposit in boreholes（e.g., lower, middle and upper） comprise the material of this study. Major, trace and REE element analyses of samples were conducted with ICP-Ms and ICP-Es methods. The Kestelek borate deposit of Miocene age was formed in playa lakes in an intermountain closed basin which was developed in volcanically and seismically active areas associated with growth faults and grabens affected the whole Anatolia at the beginning of Paleogene. Only colemanite was found as the borate mineral accompanied in lesser amount by calcite, aragonite, smectite, illite, chlorite, corrensite, heulandite and quartz. In colemanite samples, all major elements, except for Ca, show depletion trends with respect to average of earth crust and andesite. For the trace elements, Li, Cs, sb, As, sr and se are characterized by significantly high concentrations. Evaluation of element concentrations and geochemical characteristics reveal that As, Cs, sb and Li are of detrital origin, se together with B and Ca are of non-detrital and sr is indicative of both detrital and non-detrital origin. REE distributions indicate that at least two different depositional regimes prevail in the environment. Corrensite, a clay mineral forming in lake waters, is derived from volcanism. Negative Ce and positive Eu anomalies are indicative of contribution from hydrothermal solutions and fluids.

关键词： borate mineralogy geochemistry REE Kestelek Turkey.

Factors Controlling Low Uranium and Thorium Concentrations in the Cayirhan Bituminous shales(CBs)in the Beypazari(Ankara)Area,Turkey

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Acta Geologica sinica(English Edition) 2014年第1期88卷 248-252,I0009,I0010,253-259页

作者： Berna Yavuz PEHLIVANLI sükrü koc Ali sARI Hilal ENGIN Department of Geological Engineering Faculty of Engineering and Architecture Bozok University Department of Geological Engineering Faculty of Engineernig Ankara University Graduate school of Natural and Applied sciences Ankara University

In this study uranium and thorium contents and depositional characteristics of ay rhan bituminous shales（ Bs）, west of Ankara（central Anatolia）, are investigated. samples used were collected from boreholes opened by Park Holding Ltd. A total of 25 samples were taken from bituminous shale levels in boreholes drilled at 6 different locations in the study area. The H rka formation which hosts bituminous shale deposits is a volcanosedimentary sequence and all lithofacies indicate that a lacustrine environment where the water level was continuously changed. In addition to hydrocarbon generation potential, bituminous shales also accumulate significant amount of radioactive elements such as uranium and thorium. The average uranium and thorium concentrations of Bs（1.83/2.62 ppm） are much lower than averages of UC, NAsK and PAAs（uranium： 2.70/2.66/3.10 ppm; thorium： 8.50/12.30/14.60 ppm）. Low uranium contents in comparison to those of similar lacustrine environments might be attributed to that waters of depositional environment of Bs contain low concentration of dissolved uranium and redox conditions were of oxic and dioxic character. Correlation data indicate that U and Th have a similar source and are associated predominantly with clays and phosphates and dominantly with organic material. Radioactive elements in the basin might be derived from Paleozoic granites and metamorphites（e.g. gneiss, schist） which comprise the basement and volcanism which was active in the region throughout the Miocene period. These elements are probably associated with uraniferous phosphate minerals（e.g. autunite, torbernite） which occur in granite, gneiss and schist. Bs with average TOC content of 10.96 % shows very good/perfect source rock potential. Positive correlations between Gamma-Ray values and U, Th and K concentrations imply that radioactivity might be originated from these three elements.

关键词： Uranium and Thorium concentrations ay rhan bituminous shales Beypazar area Turkey

Dielectric size optimization for high power density in large-scale triboelectric nanogenerators

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Nano Research 2024年第9期17卷 8455-8464页

作者： Abdulkerim Karabiber Ömer Dirik Feyyaz koc Faruk Ozel Department of Electrical and Electronics Engineering Bingol UniversityBingol 12000Turkey Department of Metallurgical and Materials Engineering Karamanoglu Mehmetbey UniversityKaraman 70200Turkey

Triboelectric nanogenerators(TENGs)have emerged as a promising technology to harvest electrical energy from natural motions such as human movement,wind,and water *** TENGs show significant potential in small-scale applications,developing large-scale TENGs capable of generating high power remains a significant *** factors that can affect the performance of large-scale TENGs are being investigated to overcome this challenge,including the size and configuration of dielectric *** study optimizes dielectrics regarding surface area,thickness,and multicell configuration to improve harvested electrical power density in large-scale *** the studies,glass fiber was used as the positive dielectric,and multipurpose white silicone was used as the negative dielectric because of their high tribo-potential,durability,and easy *** the size optimization phase,dielectric thicknesses and surface areas that provide the maximum power density were ***,horizontal and vertical multicell configurations were examined to efficiently integrate size-optimized *** results reveal that large-scale TENGs with vertical multicell configurations can achieve high and usable energy density for *** findings provide valuable insight into the development of large-scale TENGs with advanced power generation capabilities.

关键词： triboelectric nanogenerator dielectric layer size optimization multi-cell structure high power density

土耳其中部克尔谢希尔省Phrenk地区热液成因萤石的液体包裹体研究及稀土元素地球化学特征

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地质学报 2001年第1期 44-44页

作者： sükrü koc Ali Recber 土耳其安卡拉大学地质系土耳其矿产研究和开发总局

在土耳其中部Pohrenk地区北部及东北部沿着中始新世和渐新世灰岩和泥灰岩裂缝裂隙发现有热液成因的萤石矿化。由萤石稀土元素含量获得的Tb/Ca(Tb/La和Y/Ho比值可知该萤石矿化属热液型。其负Ce异常及正Eu异常反映出热液溶液曾具有很高的... 详细信息

在土耳其中部Pohrenk地区北部及东北部沿着中始新世和渐新世灰岩和泥灰岩裂缝裂隙发现有热液成因的萤石矿化。由萤石稀土元素含量获得的Tb/Ca(Tb/La和Y/Ho比值可知该萤石矿化属热液型。其负Ce异常及正Eu异常反映出热液溶液曾具有很高的氧逸度。液体包裹体研究揭示,矿化的均一化温度在90～200℃之间,热液

关键词：稀土元素地球化学液体包裹体热液成因萤石矿 hrenk 土耳其

Customized scaffolds for large bone defects using 3D‑printed modular blocks from 2D‑medical images

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Bio-Design and Manufacturing 2024年第1期7卷 74-87页

作者： Anil AAcar Evangelos Daskalakis Paulo Bartolo Andrew Weightman Glen Cooper Gordon Blunn Bahattin koc Faculty of Engineering and Natural sciences Sabanci UniversityIstanbul 34956Türkiye D Bioprinting Laboratory Sabanci University Nanotechnology Research and Application CenterIstanbul 34956Türkiye school of Mechanical Aerospace and Civil EngineeringManchester Institute of BiotechnologyUniversity of ManchesterManchester M139PLUK singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingapore 639798Singapore school of Pharmacy and Biomedical sciences University of PortsmouthPortsmouth PO12UPUK

Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering *** use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and ***,these sophisticated techniques can be timeconsuming,labor-intensive,and ***,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma *** this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a *** modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during *** proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or *** algorithm can generate both patient-specific and average bone ***,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or *** algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM *** and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.

关键词： Additive manufacturing Modular scaffolds Large bone defect Customized scaffold design Patient-specific scaffolds

The first record of a Konservat-Lagerstätten in which early post-settlement stages of fossil archaeobalanids(Cirripedia:Balanomorpha)are preserved

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Integrative Zoology 2024年第2期19卷 200-223页

作者： Tomáš kocÍ Rok GAŠPARIC John BUCKERIDGE Martina kocOVÁ VEsELsKÁ Aleš ŠOsTER Ivancická581 PragueCzech Republic Palaeontological Department Natural History MuseumNational MuseumPragueCzech Republic Oertijdmuseum Bosscheweg 80Boxtel5293 WBThe Netherlands Institute for Palaeobiology and Evolution Novi TrgKamnikSlovenia Earth and Oceanic systems Group RMIT UniversityMelbourneAustralia Museums Victoria CarltonVictoriaAustralia Department of Paleobiology and Paleoecology Institute of Geology of the Czech Academy of SciencesPragueCzech Republic Institute of Geology and Palaeontology Charles UniversityPragueCzech Republic Faculty of Natural sciences and Engineering University of LjubljanaLjubljanaSlovenia

A diverse sessile barnacle fauna from a Miocene shallow-water deposit at Dolnja stara vas in slovenia is *** includes the first descriptions of early post settlement juveniles of Actinobalanus sloveniensis attached to mangrove *** represent three distinct growth phases,the earliest being interpreted as being less than 24 h post settlement,the others being 1 to 2 days post *** assessment of their taphonomy is *** adult balanomorphs are attached to a variety of organic substrates,including mangrove leaves and branches,fragments of the conifers?Taxodioxylon,Carapoxylon,pine cones,molluscs,and cetacean *** barnacles include ***,Amphibalanus venustus,and Perforatus perforatus—many with opercula retained within the *** retains some of the original shell *** is the second record of barnacle–plant associations from the Central Paratethys from Kamnik and *** paleoecology and paleogeography of the site are discussed.

关键词： acorn barnacles barnacle metamorphosis epibiont paleoecology taxonomy

Phylogenetic placement of bizarre karschiellid earwigs

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Insect science 2024年第3期31卷 989-992页

作者： Petr kocárek Ivona Horká Vojtěch Bonczek Markéta Kirstová Department of Biology and Ecology University of OstravaOstravaCzech Republic

Dear Editor,Karschiellidae are a mysterious group of earwigs that attract attention not only because of their interesting appearance and unexplained way of life but also mainly due to their unclear *** phylogenetic relationships of karschiellids remain speculative even 120 years since the family was described,above all due to the unavailability of DNA-grade material for molecular phylogenetic *** study includes successfully sequenced representatives of the Karschiellidae for the first time,and a probable evolutionary scheme and natural classification of karschiellids are proposed based on the constructed multigene phylogeny.

关键词： classification. phylogeny evolutionary

Construction of robust and durable Cu_(2)se-V_(2)O_(5) nanosheet electrocatalyst for alkaline oxygen evolution reaction

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Frontiers of Chemical science and Engineering 2024年第6期18卷 71-83页

作者： Tauseef Munawar Ambreen Bashir Khalid Mujasam Batoo saman Fatima Faisal Mukhtar sajjad Hussain sumaira Manzoor Muhammad Naeem Ashiq shoukat Alim Khan Muammer koc Faisal Iqbal Institute of Physics The Islamia University of BahawalpurBahawalpur 63100Pakistan King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh 11451Saudi Arabia Hybrid Materials Center(HMC) Sejong UniversitySeoul 05006Republic of Korea Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Republic of Korea Institute of Chemical sciences Bahauddin Zakariya UniversityMultan 60800Pakistan Division of sustainable Development College of Science and EngineeringHamad Bin Khalifa UniversityQatar FoundationDoha 34110Qatar

Reducing the production costs of clean energy carriers such as hydrogen through scalable water electrolysis is a potential solution for advancing the hydrogen *** the various material candidates,our group demonstrated transition-metal-based materials with tunable electronic characteristics,various phases,and ***,electrochemical water oxidation using Cu_(2)se-V_(2)O_(5) as a non-precious metallic electrocatalyst via a hydrothermal approach is *** water-splitting performance of all the fabricated electrocatalysts was evaluated after direct growth on a stainless-steel *** electrochemically tuned Cu_(2)se-V_(2)O_(5) catalyst exhibited a reduced overpotential of 128 mV and provided a reduced Tafel slope of 57 mV·dec^(−1) to meet the maximum current density of 250 mA·cm^(−2).The optimized strategy for interfacial coupling of the fabricated Cu_(2)se-V_(2)O_(5) catalyst resulted in a porous structure with accessible active sites,which enabled adsorption of the intermediates and afforded an effective charge transfer rate for promoting the oxygen evolution ***,the combined effect of the catalyst components provided long-term stability for over 110 h in an alkaline solution,which makes the catalyst promising for large-scale practical *** aforementioned advantages of the composite catalyst overcome the limitations of low conductivity,agglomeration,and poor stability of the pure catalysts(Cu2se and V2O5).

关键词： oxygen evolution reaction Cu_(2)se-V_(2)O_(5)composite nanosheets metal-diffused ions accessible adsorption sites

一家触碰不得的钢铁厂迫使荷兰人做出艰难块择

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商业周刊（中文版） 2024年第1期 33-35页

作者： Diederik Baazil Cagan koc 程玺(译) 不详

安妮·阿尔伯斯(Anne Albers)曾三获荷兰长板冲浪冠军,但她已经无法乐享其在滨海韦克(Wijk aan Zee)的“冲浪小天堂”。那是一座大约2000人的村庄,有荷兰最好的海浪,但与欧洲第二大钢铁厂塔塔钢铁(Tata steel)关联的严重健康和环境问题... 详细信息

安妮·阿尔伯斯(Anne Albers)曾三获荷兰长板冲浪冠军,但她已经无法乐享其在滨海韦克(Wijk aan Zee)的“冲浪小天堂”。那是一座大约2000人的村庄,有荷兰最好的海浪,但与欧洲第二大钢铁厂塔塔钢铁(Tata steel)关联的严重健康和环境问题也令当地备受困扰。

关键词：阿尔伯钢铁厂荷兰人冲浪