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排序方式: 共有204条查询结果,搜索用时 15 毫秒
31.
Hadiseh Taheri Mehmet Altay Unal Melike Sevim Cansu Gurcan Okan Ekim Ahmet Ceylan Zois Syrgiannis Konstantinos C. Christoforidis Susanna Bosi Ozge Ozgen Manuel Jos Gmez Mine Turktas Erken igdem Soydal Zafer Erolu Ceylan Verda Bitirim Umut Cagin Fikret Ar Asuman Ozen Ozlem Kuuk Lucia Gemma Delogu Maurizio Prato
nder Metin Aelya Yilmazer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
32.
Hadiseh Taheri Mehmet Altay Unal Melike Sevim Cansu Gurcan Okan Ekim Ahmet Ceylan Zois Syrgiannis Konstantinos C. Christoforidis Susanna Bosi Ozge Ozgen Manuel Jos Gmez Mine Turktas Erken igdem Soydal Zafer Erolu Ceylan Verda Bitirim Umut Cagin Fikret Ar Asuman Ozen Ozlem Kuuk Lucia Gemma Delogu Maurizio Prato
nder Metin Aelya Yilmazer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
33.
Rajib Ahmed Mehmet Ozgun Ozen Merve Goksin Karaaslan Cecilia A. Prator Cassandra Thanh Shreya Kumar Leonel Torres Nikita Iyer Sadie Munter Sarka Southern Timothy J. Henrich Fatih Inci Utkan Demirci 《Advanced materials (Deerfield Beach, Fla.)》2020,32(19):1907160
Metasurfaces are engineered nanostructured interfaces that extend the photonic behavior of natural materials, and they spur many breakthroughs in multiple fields, including quantum optics, optoelectronics, and biosensing. Recent advances in metasurface nanofabrication enable precise manipulation of light–matter interactions at subwavelength scales. However, current fabrication methods are costly and time-consuming and have a small active area with low reproducibility due to limitations in lithography, where sensing nanosized rare biotargets requires a wide active surface area for efficient binding and detection. Here, a plastic-templated tunable metasurface with a large active area and periodic metal–dielectric layers to excite plasmonic Fano resonance transitions providing multimodal and multiplex sensing of small biotargets, such as proteins and viruses, is introduced. The tunable Fano resonance feature of the metasurface is enabled via chemical etching steps to manage nanoperiodicity of the plastic template decorated with plasmonic layers and surrounding dielectric medium. This metasurface integrated with microfluidics further enhances the light–matter interactions over a wide sensing area, extending data collection from 3D to 4D by tracking real-time biomolecular binding events. Overall, this work resolves cost- and complexity-related large-scale fabrication challenges and improves multilayer sensitivity of detection in biosensing applications. 相似文献
34.
35.
Yunus Ozen Tunc Sertel Saime Sebnem Cetin Suleyman Ozcelik 《Journal of Electronic Materials》2018,47(12):7129-7133
The structural, optical, electrical and electrical–optical properties of a double-junction GaAsP light-emitting diode (LED) structure grown on a GaP (100) substrate by using a molecular beam epitaxy technique were investigated. The p–n junction layers of GaAs1?xPx and GaAs1?yPy, which form the double-junction LED structure, were grown with two different P/As ratios. High-resolution x-ray diffraction (HRXRD), photoluminescence (PL), and current–voltage (I–V) measurements were used to investigate the structural, optical and electrical properties of the sample. Alloy composition values (x, y) and some crystal structure parameters were determined using HRXRD measurements. The phosphorus compositions of the first and second junctions were found to be 63.120% and 82.040%, respectively. Using PL emission peak positions at room temperature, the band gap energies (Eg) of the first and second junctions were found to be 1.867 eV and 2.098 eV, respectively. In addition, the alloy compositions were calculated by Vegard’s law using PL measurements. The turn-on voltage (Von) and series resistance (Rs) of the device were obtained from the I–V measurements to be 4.548 V and 119 Ω, respectively. It was observed that the LED device emitted in the red (664.020 nm) and yellow (591.325 nm) color regions. 相似文献
36.
37.
In the present study, AISI 8620, 52100 and 440C steels were plasma paste boronized (PPB) by using 100% borax paste. PPB process was carried out in a dc plasma system at temperature of 700 and 800 °C for 3 and 5 h in a gas mixture of 70%H2–30%Ar under a constant pressure of 4 mbar. The properties of boride layer were evaluated by optical microscopy, X-ray diffraction and Vickers micro-hardness tester. X-ray diffraction analysis of boride layers on the surface of the steels revealed FeB and Fe2B phases for 52100 and 8620 steels and FeB, Fe2B, CrB and Cr2B borides for 440C steel. PPB process showed that since the plasma activated the chemical reaction more, a thicker boride layer was formed than conventional boronizing methods at similar temperatures. It was possible to establish boride layer with the same thickness at lower temperatures in plasma environment by using borax paste. 相似文献
38.
Hakan Kockar Ozen Demirbas Hilal Kuru Mursel Alper 《Journal of Materials Science: Materials in Electronics》2013,24(6):1961-1965
Ternary NiCoFe films were potentiostatically electrodeposited from the electrolytes with low (3.0) and high (3.6) pH levels, and differences in their compositional, structural, magnetic and magnetoresistance properties were studied. The compositional analysis demonstrated that the Ni content in the films decreased, and Co and Fe content increased while electrolyte pH was changed from low to high level. The structural analysis of the films was carried out using the X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD data revealed that the films have a strong (111) texture of the face-centred cubic (fcc) structure at low pH, while for the films at high pH a mixture of dominantly fcc and hexagonal closed packed structure was observed. The SEM studies showed that films grown at low pH level had comparatively larger grains than those at high pH. The magnetic characteristics studied by a vibrating sample magnetometer and magnetotransport properties were seen to be changed by the electrolyte pH. However, all films have in-plane magnetic anisotropy. The differences observed in the magnetic and magnetotransport properties were attributed to the microstructural changes caused by the electrolyte pH. 相似文献
39.
Enhanced heat transfer and pressure loss in a tube with loose-fit perforated twisted tapes were experimentally investigated. The effects of the twist ratio and the hole diameter ratio were also described. A constant twisted tape width of 52 mm, which is lower than the tube inside diameter of 56 mm, was used in order to reduce excessive pressure drops associated with full-width twisted tape elements. The tests were conducted using the tapes with three different ratios of pitch length of twisted tape to inner diameter of tube (twist ratios = 2, 2.5, 3) and three different ratios of hole to inner diameter (diameter ratios = 0.0714, 0.107, 0.143) in a range of Reynolds number 4860 to 24,130 under uniform heat flux conditions. The experimental findings revealed that the Nusselt number, friction factor, and thermal performance factor increase with decreasing twist ratio and hole diameter ratio. The maximum value of thermal performance factor of 1.27 was achieved for the case at a twist ratio of 2 and a hole diameter ratio of 0.0714. Eventually, the experimental results of Nusselt number, friction factor and thermal performance factor were correlated, and the deviations determined for Nusselt number, friction factor, and thermal performance factor were within ±7%, ±8%, and ±6%, respectively. 相似文献
40.
Ibrahim Gunes 《材料科学技术学报》2013,29(7):662-668
In the present study,AISI 8620 steel was plasma paste boronized(PPB) by using paste mixtures with different borax and B2O3 percentages.The PPB process was carried out in a DC plasma system at 973,1023 and 1073 K for 5 h in a gas mixture with 70%H2-30%Ar under a constant pressure of 103 Pa(10 mbar).The thickness of boride layers ranged from 15.9 to 53.6μm depending on the temperature and process time.The hardness of the borides formed on the surface of the steel substrate and unbonded steel substrate were 1648—1924 HV0.05 and 226 HV0.05,respectively.X-ray diffraction analysis of the boride layers on the surface of the samples were obtained for FeB and Fe2B phases.The wear tests on the steel were performed by using a ball-on-disc test device at room temperature with applied load of 10 N and with a shear velocity of 0.2 m/s.Wear test results showed that the highest value of wear rate was observed in the unborided sample while the lowest wear rate was observed in the PPB samples with 30%borax + 70%B4C paste at 1073 K for 5 h. 相似文献