Zeitschriftenartikel: „Ultra-Flat surfaces“

1

Borole, P. O., und R. S. Thakur. „Ultra-Precision Optical Flat Surfaces“. Journal of Optics 20, Nr. 2 (Juni 1991): 82–87. http://dx.doi.org/10.1007/bf03549694.

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2

Kato, Teiji, und Takayuki Nakakawaji. „Microstructures in Lubricant Thin Layers at the Magnetic Disk Surface, Observed Using Cryogenic Atomic Force Microscopy“. Australian Journal of Chemistry 59, Nr. 6 (2006): 394. http://dx.doi.org/10.1071/ch06094.

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Cryogenic Atomic Force Microscopy (AFM) was used to observe perfluoropolyether (PFPE) lubricant molecules at atomically flat solid surfaces and at a magnetic disk surface to understand the lubricity of ultra-thin (1 nm) lubricant layers at the hard disk surface. Molecular imaging of PFPE lubricant molecules reveals the formation of reversed micelle structures at comparatively non-polar solid surfaces such as gold or the carbon overcoat of magnetic disks.

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Cho, Sung-Pyo, Yoshiaki Nakamura, Jun Yamasaki, Eiji Okunishi, Masakazu Ichikawa und Nobuo Tanaka. „Microstructure and interdiffusion behaviour of β-FeSi2 flat islands grown on Si(111) surfaces“. Journal of Applied Crystallography 46, Nr. 4 (04.07.2013): 1076–80. http://dx.doi.org/10.1107/s0021889813015355.

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β-FeSi2 flat islands have been fabricated on ultra-thin oxidized Si(111) surfaces by Fe deposition on Si nanodots. The microstructure and interdiffusion behaviour of the β-FeSi2/Si(111) system at the atomic level were studied by using spherical aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and energy dispersive X-ray spectroscopy. The formed β-FeSi2 flat islands had a disc shape with an average size of 30–150 nm width and 10–20 nm height, and were epitaxically grown on high-quality single-phase Si with a crystallographic relationship (110)β-FeSi2/(111)Si and [001]β-FeSi2/[1\bar 10]Si. Moreover, the heterojunction between the β-FeSi2(110) flat islands and the Si(111) substrate was an atomically and chemically abrupt interface without any irregularities. It is believed that these results are caused by the use of ultra-thin SiO2 films in our fabrication method, which is likely to be beneficial particularly for fabricating practical nanoscaled devices.

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Blackstock, Jason J., Zhiyong Li, Mark R. Freeman und Duncan R. Stewart. „Ultra-flat platinum surfaces from template-stripping of sputter deposited films“. Surface Science 546, Nr. 2-3 (Dezember 2003): 87–96. http://dx.doi.org/10.1016/j.susc.2003.09.039.

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5

Hirayama, Hiroyuki. „Growth of atomically flat ultra-thin Ag films on Si surfaces“. Surface Science 603, Nr. 10-12 (Juni 2009): 1492–97. http://dx.doi.org/10.1016/j.susc.2008.09.057.

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6

Zhang, Kai, Alexandra Arranja, Hongyu Chen, Serhii Mytnyk, Yiming Wang, Sander Oldenhof, Jan H. van Esch und Eduardo Mendes. „A nano-fibrous platform of copolymer patterned surfaces for controlled cell alignment“. RSC Advances 8, Nr. 39 (2018): 21777–85. http://dx.doi.org/10.1039/c8ra03527j.

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A method to transfer-print quenched, ultra-long copolymer cylindrical micelles to a flat surface and the use of these nano-structures to promote spontaneous cell alignment is proposed. Endless possibilities of corona end-group chemical modification provide a new tool to control cell response.

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Jiang, Li, Tao Wang und Christian A. Nijhuis. „Fabrication of ultra-flat silver surfaces with sub-micro-meter scale grains“. Thin Solid Films 593 (Oktober 2015): 26–39. http://dx.doi.org/10.1016/j.tsf.2015.09.023.

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8

Masens, Carl, Jurgen Schulte, Matthew Phillips und Svetlana Dligatch. „Ultra Flat Gold Surfaces for Use in Chemical Force Microscopy: Scanning Probe Microscopy Studies of the Effect of Preparation Regime on Surface Morphology“. Microscopy and Microanalysis 6, Nr. 2 (März 2000): 113–20. http://dx.doi.org/10.1007/s100059910010.

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The preparation of ultra flat gold surfaces for use in chemical force microscopy (CFM) has been studied. The surfaces were studied in terms of substrate effects by comparing mica, Si (110) wafer and glass slides. The effect of different annealing regimes was also investigated. Measurements on these surfaces were made by both atomic force microscopy (AFM) (in contact and tapping mode) and by scanning tunneling microscopy (STM). The films contain different morphologies with respect to grain size and topography. Calculations of surface roughness present values less than 2.5 nm for all surfaces studied, making the choice of the flattest surface difficult if based on criteria of surface roughness alone. Additionally, it is shown that different acquisition parameters can produce dissimilar images that have stability and reproducibility.

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Sander, Tim, Yi Liu, Tuan Anh Pham, Maximilian Ammon, Mirunalini Devarajulu und Sabine Maier. „Ultra-high vacuum cleaver for the preparation of ionic crystal surfaces“. Review of Scientific Instruments 93, Nr. 5 (01.05.2022): 053703. http://dx.doi.org/10.1063/5.0088802.

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Cleaving single crystals in situ under ultra-high vacuum conditions provides a reliable and straightforward approach to prepare clean and atomically well-defined surfaces. Here, we present a versatile sample cleaver to efficiently prepare ionic crystal surfaces under ultra-high vacuum conditions, which is suitable for preparation of softer materials, such as alkali halides, and harder materials, such as metal oxides. One of the advantages of the presented cleaver design is that the cleaving blade and anvil to support the crystal are incorporated into the device. Therefore, no particularly strong mechanical manipulator is needed, and it is compatible with existing vacuum chambers equipped with an xyz-manipulator. We demonstrate atomically flat terraces and the atomic structure of NaCl(001), KBr(001), NiO(001), and MgO(001) cleavage planes prepared in situ under ultra-high vacuum conditions and imaged by low-temperature non-contact atomic force microscopy.

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Gajdardziska-Josifovska, M., B. G. Frost, E. Völkl und L. F. Allard. „On the Faceting of Polar Ceramic Surfaces: Microscopy and Holography Studies of MGO(111) Surfaces“. Proceedings, annual meeting, Electron Microscopy Society of America 54 (11.08.1996): 366–67. http://dx.doi.org/10.1017/s0424820100164295.

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Polar surfaces are those crystallographic faces of ionically bonded solids which, when bulk terminated, have excess surface charge and a non-zero dipole moment perpendicular to the surface. In the case of crystals with a rock salt structure, {111} faces are the exemplary polar surfaces. It is commonly believed that such polar surfaces facet into neutral crystallographic planes to minimize their surface energy. This assumption is based on the seminal work of Henrich which has shown faceting of the MgO(111) surface into {100} planes giving rise to three sided pyramids that have been observed by scanning electron microscopy. These surfaces had been prepared by mechanical polishing and phosphoric acid etching, followed by Ar+ sputtering and 1400 K annealing in ultra-high vacuum (UHV). More recent reflection electron microscopy studies of MgO(111) surfaces, annealed in the presence of oxygen at higher temperatures, have revealed relatively flat surfaces stabilized by an oxygen rich reconstruction. In this work we employ a combination of optical microscopy, transmission electron microscopy, and electron holography to further study the issue of surface faceting.

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Liu, Yan Yan, Laura G. Gladkis und Heiko Timmers. „Micro-Scratching of UHMW Polyethylene Surfaces“. Materials Science Forum 654-656 (Juni 2010): 2455–58. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.2455.

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Ultra-high molecular weight polyethylene has been micro-scratched with 90° cube corner tips. The scratch mode was flat-on, uni-directional and single pass. The micro-scratches and cross-sectional scratch profiles were characterised with atomic force microscopy. No detached debris is produced. Cross-sectional scratch profiles have been analysed using Zum Gahr’s formalism giving an fab ratio slightly above zero. This is consistent with expectation for ductile polymers where none or little detached debris is produced. However, the observation contrasts with that for other polymers, such as PMMA, PEP and PC, for which inconclusive results suggest an excess pile-up implying an inconceivable change of mass density or material gain.

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Kirino, Okiharu, und Toshiyuki Enomoto. „Ultra-flat and ultra-smooth Cu surfaces produced by abrasive-free chemical–mechanical planarization/polishing using vacuum ultraviolet light“. Precision Engineering 35, Nr. 4 (Oktober 2011): 669–76. http://dx.doi.org/10.1016/j.precisioneng.2011.05.005.

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Choyke, Wolfgang J., B. D'Urso, Fei Yan und Robert P. Devaty. „Ultra-Precision Machining of Stainless Steel and Nickel with Single Crystal 4H and 6H Boule SiC“. Materials Science Forum 645-648 (April 2010): 853–56. http://dx.doi.org/10.4028/www.scientific.net/msf.645-648.853.

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Ultra-precision machining is dominated by single-crystal diamond cutting tools, and is typically applied to a narrow range of materials, particularly aluminum and copper. Single-crystal SiC can be comparable to some diamonds in hardness and thermal conductivity, while potentially having superior chemical and thermal stability, yet it has not been explored as a cutting tool for ultra-precision machining. We made two cutting tools with single-crystal SiC, one with sharp corners and one with a large circular radius, and used them to cut flat surfaces on two materials, 316 stainless steel and nickel. These materials generally cause unacceptably rapid diamond tool wear. We report the average roughness of the resulting surfaces cut with single-crystal 4H and 6H SiC tools.

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Farina, Filippo, Giorgio Ercolano, Sara Cavaliere, Deborah Jones und Jacques Rozière. „Surface-Limited Electrodeposition of Continuous Platinum Networks on Highly Ordered Pyrolytic Graphite“. Nanomaterials 8, Nr. 9 (13.09.2018): 721. http://dx.doi.org/10.3390/nano8090721.

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Continuous thin platinum nanoplatelet networks and thin films were obtained on the flat surface of highly ordered pyrolytic graphite (HOPG) by high overpotential electrodeposition. By increasing the deposition time, the morphology of the Pt deposits can be progressively tuned from isolated nanoplatelets, interconnected nanostructures, and thin large flat islands. The deposition is surface-limited and the thickness of the deposits, equivalent to 5 to 12 Pt monolayers, is not time dependent. The presence of Pt (111) facets is confirmed by High Resolution Transmission Electron Microscopy (HRTEM) and evidence for the early formation of a platinum monolayer is provided by Scanning Transmission Electron Microscopy and Energy Dispersive X-rays Spectroscopy (STEM-EDX) and X-ray Photoelectron Spectroscopy (XPS) analysis. The electroactivity towards the oxygen reduction reaction of the 2D deposits is also assessed, demonstrating their great potential in energy conversion devices where ultra-low loading of Pt via extended surfaces is a reliable strategy.

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Beyer, Hannes, Tino Wagner und Andreas Stemmer. „Length-extension resonator as a force sensor for high-resolution frequency-modulation atomic force microscopy in air“. Beilstein Journal of Nanotechnology 7 (15.03.2016): 432–38. http://dx.doi.org/10.3762/bjnano.7.38.

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Frequency-modulation atomic force microscopy has turned into a well-established method to obtain atomic resolution on flat surfaces, but is often limited to ultra-high vacuum conditions and cryogenic temperatures. Measurements under ambient conditions are influenced by variations of the dew point and thin water layers present on practically every surface, complicating stable imaging with high resolution. We demonstrate high-resolution imaging in air using a length-extension resonator operating at small amplitudes. An additional slow feedback compensates for changes in the free resonance frequency, allowing stable imaging over a long period of time with changing environmental conditions.

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Liu, Rui, Tiesheng Wu, Yiping Wang, Zhihui Liu, Weiping Cao, Dan Yang, Zuning Yang, Yan Liu und Xu Zhong. „Ultra-Short Polarization Rotator Based on Flat-Shaped Photonic Crystal Fiber Filled with Liquid Crystal“. Materials 15, Nr. 21 (27.10.2022): 7526. http://dx.doi.org/10.3390/ma15217526.

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In this study we demonstrate a high-performance polarization rotator (PR) based on flat-shaped photonic crystal fiber. The flat surfaces of the fiber are plated on gold films as electrodes, and the core of the structure is filled with liquid crystal. The polarization rotation characteristics of the flat-shaped fiber can be effectively adjusted by applying external voltage. The optical properties are analyzed using the finite element method (FEM). The results show that the magnitude of the modulation voltage is closely related to the thickness of the flat fiber. When the fiber thickness is 20 μm, only 100 V is required to achieve the highest PR performance. In the wavelength of the 1.55 μm band (~200 nm bandwidth), the conversion length of the PR is only 3.99 μm, the conversion efficiency is close to 100%, and the minimum crosstalk value is −26.2 dB. The presented PR, with its excellent performance, might enable promising applications in the communication system and the photonic integrated circuits.

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Yuan, Zheng, Yi Fan Dai, Xu Hui Xie und Lin Zhou. „Ion Beam Figuring System for Ultra-Precise Optics“. Key Engineering Materials 516 (Juni 2012): 19–24. http://dx.doi.org/10.4028/www.scientific.net/kem.516.19.

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Ion beam figuring (IBF) is a novel technology for Ultra-precise optics. Material is removed from optic surface in atomic or molecular form by physical sputtering. Due to non-contact between the tool and the work piece, the problems involved in the conventional process are avoided, such as edge-effect and tool-wear. The ion beam figuring process is of high determinacy and high efficiency. All these properties make ion beam figuring one of the promising methods for producing mirrors of high precision with nm-rms accuracy. In this article, a new ion beam figuring system which contains doubled vacuum chambers is set up. Optics can be exchanged by a transport vehicle shuttling between the two vacuum chambers without opening the primary vacuum chamber and waiting for the ion source to cool completely, which means the efficiency can be increased greatly. A high performance processing robot contains three linear axes and two angular axes of motion, providing 5-axis ion source positioning capability with high accuracy. The angle can be up to 50° to figure very steep spherical and aspherical surfaces. Then, the beam removal function of Gaussian shape is obtained by an experimental method and it is extremely stable for a long time. Finally, two sample mirrors are figured by the ion beam figuring system: one is a fused silica flat mirror with a 100 mm diameter (90% effective aperture) and an ultra-precise flat mirror with a surface error of 0.89 nm rms, 14.7 nm PV is obtained; the other fused silica concave spherical mirror with a 100 mm aperture (90% effective aperture) and 420 mm radius of curvature is figured and a concave spherical mirror with 1 nm rms, 16.9 nm PV is obtained, which prove that the ion beam figuring system is favourable for the figuring process.

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Yang, HaiJun, ZhengChi Hou und Jun Hu. „Surface modification of ultra-flat polydimethylsiloxane by UV-grafted poly(acrylic acid) brushes“. Journal of Applied Polymer Science 123, Nr. 4 (24.08.2011): 2266–71. http://dx.doi.org/10.1002/app.34563.

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Ahmed, Rezwan, Takeshi Nakagawa und Seigi Mizuno. „Structure determination of ultra-flat stanene on Cu(111) using low energy electron diffraction“. Surface Science 691 (Januar 2020): 121498. http://dx.doi.org/10.1016/j.susc.2019.121498.

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Haidar, Fatima, Mathieu Maas, Andrea Piarristeguy, Annie Pradel, Sara Cavaliere und Marie-Christine Record. „Ultra-Thin Platinum Deposits by Surface-Limited Redox Replacement of Tellurium“. Nanomaterials 8, Nr. 10 (15.10.2018): 836. http://dx.doi.org/10.3390/nano8100836.

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Platinum is the most employed electrocatalyst for the reactions taking place in energy converters, such as the oxygen reduction reaction in proton exchange membrane fuel cells, despite being a very low abundant element in the earth’s crust and thus extremely expensive. The search for more active electrocatalysts with ultra-low Pt loading is thus a very active field of investigation. Here, surface-limited redox replacement (SLRR) that utilizes the monolayer-limited nature of underpotential deposition (UPD) was used to prepare ultrathin deposits of Pt, using Te as sacrificial metal. Cyclic voltammetry and anodic potentiodynamic scanning experiments have been performed to determine the optimal deposition conditions. Physicochemical and electrochemical characterization of the deposited Pt was carried out. The deposit comprises a series of contiguous Pt islands that form along the grain interfaces of the Au substrate. The electrochemical surface area (ECSA) of the Pt deposit obtained after 5 replacements, estimated to be 18 m2/g, is in agreement with the ECSA of extended surface catalysts on flat surfaces.

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Li, Xiang, Akinobu Teramoto, Tomoyuki Suwa, Rihito Kuroda, Shigetoshi Sugawa und Tadahiro Ohmi. „Formation speed of atomically flat surface on Si (100) in ultra-pure argon“. Microelectronic Engineering 88, Nr. 10 (Oktober 2011): 3133–39. http://dx.doi.org/10.1016/j.mee.2011.06.014.

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Xue, Xiu Li, Yi Luo und Pei Rong Zhao. „Ultimate Potential Nature Gas Resource Prediction and Exploration Direction in Sichuan Basin“. Advanced Materials Research 998-999 (Juli 2014): 1498–503. http://dx.doi.org/10.4028/www.scientific.net/amr.998-999.1498.

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The ultimate natural gas resources of Sichuan Basin were predicted by the application of hydrocarbon reservoir scale sequence method. The results revealed that a total of 236 gas reservoirs exist in Sichuan Basin, with total expected natural gas resources of 57718×108m3.110 gas reservoirs are undiscovered, with geological reserves of 4.04×1012m3, accounting for70.0% of the total natural gas resources, among which, 17 undiscovered gas reservoirs have resources of more than 1000×108m3, 13 undiscovered natural gas reservoirs have resources of 500-1000×108m3 and 15 undiscovered gas reservoirs have resources of 100-500×108m3. The undiscovered natural gas resources mainly lie in the following key exploration fields: Permian-Triassic reef flat reservoir of Huankaijiang-Liangping continental shelf and deep to ultra-deep layers of continental Xujiahe Formation in West Sichuan, medium to shallow layers of Northeast Sichuan and Central Sichuan focused on Xujiahe Formation, piedmont zone of Longmen Mountain and Micang-Daba Mountain, oolitic flat of Jialingjiang Formation of East Sichuan, South Sichuan and North Sichuan as well as five large sets of unconformity surfaces, namely top surface of Sinian Dengying Formation, top surface of Middle-Upper Ordovician, top surface of Middle Carboniferous, top surface of Permian Yangxin Series and top surface of Leikoupo Formation.

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Kennedy, F. E., S. C. Cullen und J. M. Leroy. „Contact Temperature and Its Effects in an Oscillatory Sliding Contact“. Journal of Tribology 111, Nr. 1 (01.01.1989): 63–69. http://dx.doi.org/10.1115/1.3261880.

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The relationship between contact temperature, friction coefficient, and wear rate was studied here for the case of dry sliding between pin and flat in small amplitude oscillatory motion. In the first part of the study, infrared radiation pyrometry and finite element analysis techniques were used to measure and model surface temperatures in an oscillatory contact. Good agreement was achieved between model predictions and experimental measurements. The model was then applied to an oscillating contact between an ultra-high molecular weight polyethylene pin and a rough stainless steel flat. Temperature predictions for that case were correlated with measured friction coefficients and wear rates. It was found that the polyethylene wear rate decreased as the contact temperature increased. The uniformity and thickness of the transfer films which formed on both counterface and polymer pin were found to be affected by contact temperature. Transfer film behavior was deemed responsible for the influence of contact temperature on wear rate.

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Shimiuzu, Tomoki, Mitsuru Ohtake, Masaaki Futamoto, Fumiyoshi Kirino und Nobuyuki Inaba. „Formation of $L1_{0}$ -FePt(001) Ultra-Thin Films With Flat Surfaces Using VC and VN Underlayers“. IEEE Transactions on Magnetics 53, Nr. 11 (November 2017): 1–4. http://dx.doi.org/10.1109/tmag.2017.2700489.

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Kwac, Lee Ku, Jae Yeol Kim und Young Tae Cho. „Motion and Environment Error Compensation for Ultra-Precision Lathe“. Key Engineering Materials 297-300 (November 2005): 2339–44. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.2339.

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Recently, the demand for Ultra-precision products is rapidly increasing, especially in such industries as semi-conductors, computers, aerospace, and precision machinary. Ultra-precision processing is also extremely needed for NT in the field of mechanical engineering. Lately, together with drastic advancement of electronic and photonics industry, the need of Ultra-precision processing is increased in the manufacturing of various kernel parts, which are connected with these industrial fields. Especially, motion accuracy to nanometers is required in order in stroke of hundreds millimeters according as the diameter of the processed object great and the processing accuracy rises. In this case, the response speed absolute delay due to inertial mass of the moving parts is very large. Therefore, real-time motion error compensation becomes the barest necessity. In this paper, we used ultra-precision cutting unit (UPCU) to cope with the problem. A special UPCU was designed and tested to obtain sub-micrometer from accuracy in diamond turning of flat surfaces. The thermal growth spindle error was compensated in real time using the UPCU driven by piezoelectric actuator along with a laser encoder displacement sensor.

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Costache, Andrei, Christian Berggreen, Ion Marius Sivebæk und Kristian Glejbøl. „Numerical investigation of friction joint between Basalt Fiber Reinforced Composites and aluminum“. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 231, Nr. 5 (14.07.2016): 543–51. http://dx.doi.org/10.1177/1350650116659183.

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Flexible risers are used in the offshore oil industry for exporting hydrocarbons from subsea equipment to floating production and storage vessels. The latest research in unbonded flexible pipes aims to reduce weight by replacing metal components with composite materials. This would result in lighter and stiffer flexible risers, which would be well suited for ultra deep water applications. This paper develops a new finite element model used for evaluating the efficiency of anchoring flat unidirectional fiber reinforced tendons in a mechanical grip. It consists two flat grips with the fiber reinforced tendon in between. The grips are pressed against the composite and the pullout force is ensured through friction. The novelty of the paper is represented by the detailed investigation of the influence between the coefficient of friction and the pullout force. By comparing numerical and experimentally obtained results, it is possible to show the importance of friction decay in the grip. Improper contact between the grips and composite is also taken into account and leads to good agreement between numerical and experimental results. This study shows how to avoid over-estimating the efficiency of such grip by using dry friction in finite element models.

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Wu, Jinzhong, Shaohui Yin, Shengjie Yang und Yuanfan Guo. „Study on magnetorheological nano-polishing using low-frequency alternating magnetic field“. Advances in Mechanical Engineering 12, Nr. 1 (Januar 2020): 168781401990072. http://dx.doi.org/10.1177/1687814019900721.

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With the development of electronics and optical industry, the high-efficiency ultra-precision polishing technologies of flat and curved surfaces are in high demand. The traditional magnetorheological polishing technology, using flexible polishing head, has the disadvantages of low polishing efficiency and small processing area. In this study, a novel tray-type magnetorheological polishing process using low-frequency alternating magnetic field excitation was developed to improve the efficiency of magnetorheological polishing for large surfaces and to make polishing magnetorheological cluster generate a cyclical fluctuation up and down, and then improve the cross-cutting effects of abrasives. With the developed excitation system, a large bowl-shaped varying magnetic field was generated in the working area, and the effects of current frequency, working gap, trough rotation speed, and workpiece rotation speed on the improvement rate of surface roughness and material removal rate were systematically investigated. A series of experiments were conducted on K9 glass specimens to verify the polishing performance. Experimental results show that the surface roughness of K9 glass was improved from 567.08 to 9.63 nm in 120 min.

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Bao, Si-Yao, Xing Deng, Feng Mao, Ni Zhong, Fang-Yu Yue, Lin Sun, Ping-Hua Xiang und Chun-Gang Duan. „Ultra-flat ITO films on mica for high temperature transparent flexible electrodes“. Ceramics International 46, Nr. 2 (Februar 2020): 2268–72. http://dx.doi.org/10.1016/j.ceramint.2019.09.215.

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Mundschau, M., E. Bauer und W. ᔒwięch. „Methods and Applications of UV Photoelectron Microscopy in Surface Science“. Proceedings, annual meeting, Electron Microscopy Society of America 48, Nr. 1 (12.08.1990): 564–65. http://dx.doi.org/10.1017/s0424820100181579.

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Photoelectron microscopy is sensitive to single atomic or molecular layers on surfaces at submonolayer coverages. A significant advance for fundamental studies in surface science has been the construction of ultra-high vacuum versions of classical photoelectron microscopes and the combination with other techniques of surface analysis - most notably low-energy electron diffraction and microscopy. This is essential for the proper interpretation of the micrographs. The technique is well suited for in situ studies of large flat samples such as silicon wafers, single crystals and polished metallurgical samples.One of the most promising fields for application of the photoelectron microscope is in the area of epitaxial growth.In epitaxy a crystalline substance grows as an oriented overgrowth atop a substrate. It has widespread use in the semiconductor industry and in the field of quantum electronics, in which epitaxially grown structures have the dimensions of the same order of magnitude as the wavelengths of the conducting electrons.

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Xiong, Wan-Sheng, Yun Jiang, Yu Xia, Yuyang Qi, Weiwei Sun, Dan He, Yumin Liu und Xing-Zhong Zhao. „A robust 3D host for sodium metal anodes with excellent machinability and cycling stability“. Chemical Communications 54, Nr. 68 (2018): 9406–9. http://dx.doi.org/10.1039/c8cc03996h.

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A robust and ultra-stable sodium infiltrated Fe₂O₃ coated carbon textile (SFCT) anode has been designed. This SFCT anode overcomes the disadvantage of Na electrodes, which is not easily processable, and exhibits more flat voltage profiles, lower stripping/plating overpotential, and better cycling stability in an additive-free carbonate-based electrolyte compared with bare Na electrodes.

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Bhogra, Meha, und Umesh V. Waghmare. „Flat Phonon Band-Based Mechanism of Amorphization of MOF-5 at Ultra-low Pressures“. Journal of Physical Chemistry C 125, Nr. 27 (06.07.2021): 14924–31. http://dx.doi.org/10.1021/acs.jpcc.1c02598.

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Liu, Maolin, Changqing Lin, Weicheng Ou, Han Wang, Chunyang Pan, Yuchen Ji und Hehui Zheng. „Electrohydrodynamic Printing of PCL@CsPbBr3 Composite Fibers with High Luminescence for Flexible Displays“. Coatings 13, Nr. 3 (24.02.2023): 500. http://dx.doi.org/10.3390/coatings13030500.

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Metal halide perovskite quantum dots (PQDs) are widely used in the display field due to their excellent photoelectric properties, such as ultra-narrow half-peak widths and ultra-pure luminescence color purity. Inkjet printing, laser direct writing and electrospinning are all common methods for PQDs printing to prepare micropattern displays. In order to produce large-scale and high-resolution PQDs micropatterns, electrohydrodynamic (EHD) printing technology is capable of large-scale deposition of highly oriented nanofibers on rigid or pliable, flat or bent substrates with the advantages of real-time regulation and single control. Therefore, it has a lot of potential in the fabrication of pliable electronic devices for one-dimensional ordered light-emitting fibers. Polycaprolactone (PCL) as an EHD printing technology polymer material has the advantages of superior biocompatibility, a low melting point, saving energy and easy degradation. By synthesizing CsPbBr3 quantum dots (QDs) and PCL composite spinning stock solution, we used the self-built EHD printing platform to prepare the PCL@CsPbBr3 composite light-emitting optical fiber and realized the flexible display of high-resolution micropatterns in polydimethylsiloxane (PDMS) packaging. An x-ray diffractometer (XRD), scanning electron microscope (SEM) and photoluminescence (PL) were used to characterize and analyze the fiber’s morphology, phase and spectral characteristics. EHD printing technology may open up interesting possibilities for flexible display applications based on metal halide PQDs.

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Prange, Andreas, und Heinrich Schwenke. „Trace Element Analysis using Total-Reflection X-Ray Fluorescence Spectrometry“. Advances in X-ray Analysis 35, B (1991): 899–923. http://dx.doi.org/10.1154/s0376030800013100.

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AbstractFor the application of TXRF in trace element analysis, two characteristic features of the total reflection of X-rays are exploited. These are the high reflectivity on flat surfaces and the low penetration depth of the primary radiation. This allows the application of TXRF for both chemical trace and ultra-trace element analysis on the one hand and surface analysis on the other. For chemical trace clement analysis, total reflection on a highly polished substrate is characterized by a high reflectivity, which leads to a drastic reduction of the spectral background. The sample to be analyzed is prepared on the substrate as a residue of small quantities by evaporation from solutions or fine-grained suspensions. Instrumental detection limits of a few pg or sub-ng/ ml−1 arc state of the art for commercially available equipment. Besides the high detection power, internal standardization is another important feature of TXRF, enabling very simple quantification of the detected elements. The small sample mass required enables especially ultra-micro analytical questions to be tackled. For trace element analysis in surfaces the low penetration depth of the primary radiation under the conditions of total reflection is exploited. The penetration depth is in the range of a few nanometers, hence, TXRF is intrinsically surface sensitive. Detection limits better than 1010 atoms/cm2 are obtained for metal impurities on silicon wafers. For the examination of layered structures elemental composition, layer thickness, and density can be derived from die angle-dependent fluorescence intensities. The present paper describes the basic features of the total reflection of X-rays and gives some representative examples of the different uses of TXRF in trace element analysis.

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Spence, J. C. H., X. Zhang, J. M. Zuo, U. Weierstall, E. Munro und J. Rouse. „Low-energy point-reflection EM“. Proceedings, annual meeting, Electron Microscopy Society of America 53 (13.08.1995): 610–11. http://dx.doi.org/10.1017/s0424820100139421.

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The limited penetration of the low-voltage point-projection microscope (PPM) may be avoided by using the reflection geometry to image clean surfaces in ultra-high vacuum. Figure 1 shows the geometry we are using for experimental point-reflection (PRM) imaging. A nanotip field-emitter at about 100 - 1000 volts is placed above a grounded atomically flat crystalline substrate, which acts as a mirror and anode. Since most of the potential is dropped very close to the tip, trajectories are reasonably straight if the sample is in the far-field of the tip. A resolution of 10 nm is sought initially. The specular divergent RHEED beam then defines a virtual source S' below the surface, resulting in an equivalent arrangement to PPM (or defocused CBED). Shadow images of surface asperities are then expected on the distant detector, out of focus by the tip-to-sample distance. These images can be interpreted as in-line electron holograms and so reconstructed (see X. Zhang et al, these proceedings). Optical analog experiments confirm the absence of foreshortening when the detector is parallel to the surface.

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Chaluvadi, Sandeep, Debashis Mondal, Chiara Bigi, Jun Fujii, Rajdeep Adhikari, Regina Ciancio, Alberta Bonanni et al. „Direct-ARPES and STM Investigation of FeSe Thin Film Growth by Nd:YAG Laser“. Coatings 11, Nr. 3 (26.02.2021): 276. http://dx.doi.org/10.3390/coatings11030276.

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Research on ultrathin quantum materials requires full control of the growth and surface quality of the specimens in order to perform experiments on their atomic structure and electron states leading to ultimate analysis of their intrinsic properties. We report results on epitaxial FeSe thin films grown by pulsed laser deposition (PLD) on CaF2 (001) substrates as obtained by exploiting the advantages of an all-in-situ ultra-high vacuum (UHV) laboratory allowing for direct high-resolution surface analysis by scanning tunnelling microscopy (STM), synchrotron radiation X-ray photoelectron spectroscopy (XPS) and angle-resolved photoemission spectroscopy (ARPES) on fresh surfaces. FeSe PLD growth protocols were fine-tuned by optimizing target-to-substrate distance d and ablation frequency, atomically flat terraces with unit-cell step heights are obtained, overcoming the spiral morphology often observed by others. In-situ ARPES with linearly polarized horizontal and vertical radiation shows hole-like and electron-like pockets at the Γ and M points of the Fermi surface, consistent with previous observations on cleaved single crystal surfaces. The control achieved in growing quantum materials with volatile elements such as Se by in-situ PLD makes it possible to address the fine analysis of the surfaces by in-situ ARPES and XPS. The study opens wide avenues for the PLD based heterostructures as work-bench for the understanding of proximity-driven effects and for the development of prospective devices based on combinations of quantum materials.

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Yeadon, M., M. T. Marshall und J. M. Gibson. „In-Situ Transmission Elecron Microscopy (TEM) Study of the Nitridation of Basal Plane Sapphire by Reactive Molecular Beam Epitaxy (RMBE)“. Microscopy and Microanalysis 3, S2 (August 1997): 475–76. http://dx.doi.org/10.1017/s1431927600009260.

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Group III-nitride thin films are currently of great interest for use in wide-bandgap semiconductor applications including UV lasers and light emitting diodes (LEDs). Sapphire (a-Al2O3) is currently the substrate of choice for the growth of GaN despite a large lattice mismatch. Growth of high quality GaN epilayers typically involves the deposition of a buffer layer of either AIN or GaN at a temperature well below that used for the growth of the active GaN layer. It has been found empirically that nitridation of the sapphire surface with nascent nitrogen prior to growth of the buffer layer results in a substantial improvement in film quality. Using a novel ultra-high vacuum (UHV) in-situ TEM with in-situ RMBE, we have studied the nitridation of the (0001) sapphire surface using transmission and reflection electron microscopy (REM), reflection high energy electron diffraction (RHEED) and Auger electron spectroscopy (AES).An electron-transparent sapphire TEM sample was annealed at 1400°C for 12 hours in flowing oxygen, to form atomically flat surfaces for our investigation.

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Lim, Jong Hyeuk, Kyong Nam Kim, Gwang Ho Gweon, Jae Beom Park und Geun Young Yeom. „Study of Internal Linear Inductively Coupled Plasma Source for Ultra Large-Scale Flat Panel Display Processing“. Plasma Chemistry and Plasma Processing 29, Nr. 4 (16.05.2009): 251–59. http://dx.doi.org/10.1007/s11090-009-9176-0.

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Kolesnychenko, O. Yu, R. de Kort und H. van Kempen. „Atomically flat ultra-clean Cr(001) surfaces produced by cleavage of a single crystal: scanning tunneling microscopy and spectroscopy study“. Surface Science 490, Nr. 1-2 (September 2001): L573—L578. http://dx.doi.org/10.1016/s0039-6028(01)01341-3.

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Bamberg, Simon, Vijay Sukumaran, Venky Sundaram, Rao Tummala, Johannes Etzkorn und Frank Brüning. „Improvement of Plated Copper Adhesion in Glass Interposer Applications“. Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2012, DPC (01.01.2012): 001807–26. http://dx.doi.org/10.4071/2012dpc-wp16.

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Glass interposers offer a compelling alternative to silicon interposers with highest I/Os and excellent electrical performance, with potential for low cost from large panel processing. For sub-32nm IC nodes and 3D-IC packages at fine I/O pitch, organic substrates are reaching their limits in terms of I/Os, design rules and CTE mismatch. Glass offers the best combination of electrical insulation, dimensional stability, CTE match to Si ICs, and flat, smooth surfaces for ultra-fine line lithography. The biggest challenge in glass interposers is the formation and metallization of ultra-fine pitch through vias. The formation of small via diameters in thin glass substrate have been demonstrated. The focus of this paper will be on wet metallization of glass interposer with through via, and addressing the challenge of providing reliable adhesion on the copper-to-glass interface. Two main approaches are currently pursued in the wet-chemical metallization of glass interposers: the electroless and electrolytic copper deposition on a) bare glass with photo-structured or laser-ablated through vias and b) the deposition on an intermediate polymer surface layer, requiring glass metallization only on the via sidewalls. Therefore, in addition to the analysis and optimization of adhesion-improving techniques on different glass types, their performance on different polymer liners is also assessed. The techniques include surface conditioning with cationic polyectrolytes and deposition of silica. The effect of the above surface pretreatments on plated copper adhesion is analyzed and the results provide guidelines for reliable glass interposer TPV metallization.

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Frimmel, F. H., F. Saravia und A. Gorenflo. „NOM removal from different raw waters by membrane filtration“. Water Supply 4, Nr. 4 (01.12.2004): 165–74. http://dx.doi.org/10.2166/ws.2004.0074.

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In this study natural organic matter (NOM) removal by ultra- and nanofiltration from four different raw waters was investigated. The experiments were carried out with a flat channel cross flow unit and with a pilot unit equipped with two parallel spiral wound modules. NOM rejection was characterized using 13CMAS-NMR spectroscopy, scanning electron microscopy (SEM) and size exclusion chromatography with online DOC detection (LC-OCD). Additionally measurements, such as DOC, UVA (254nm and 436nm), AOX- and THM-precursors, ion concentration, turbidity, etc. were made on raw waters, permeates and concentrates. The results indicate that NOM removal by nanofiltration for all water sources is almost complete (>90%), while NOM removal by ultrafiltration depends on raw water chemistry, especially ionic strength. Solid state 13C-NMR spectra of freeze-dried NOM deposits on membrane surfaces suggest the presence of structural polysaccharides (such as chitin and cellulose). SEM images confirm the NMR-results: after filtration, inorganic deposits and algae like structures were found on membrane surfaces.

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Agnew, James W., Steven B. Hammer, Alexandre L. Roy und Amina Rahmoune. „Central and peripheral pain sensitization during an ultra-marathon competition“. Scandinavian Journal of Pain 18, Nr. 4 (25.10.2018): 703–9. http://dx.doi.org/10.1515/sjpain-2018-0079.

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Abstract Background and aims The participation in ultra-marathons and other ultra-endurance events has increased exponentially over the past decade. There is insufficient data on variation in pain mechanisms in exercise overall but especially in the ultra-endurance athlete population. To further understand peripheral and central pain sensitization we have investigated pressure pain threshold and conditioned pain modulation during three separate ultra-marathon competitions. Methods Each ultra-marathon investigated was held in the state of Florida, USA, over flat, sandy and paved surfaces under generally warm to hot, humid conditions. Pressure pain threshold was measured utilizing a Baseline © Dolorimeter. The blunt end of the dolorimeter stylus was placed onto the distal dominant arm, equidistant between the distal radius and ulna, three times in a blinded manner to insure that the testing technician did not influence the subject’s responses. Conditioned pain modulation was measured immediately after the PPT measures by placing the non-dominant hand in a cool water bath maintained at 15°C. The same dolorimeter measurement was repeated two more times on the dominant arm while the non-dominant hand remained in the water. Data was analyzed with a paired t-test. Results Pressure pain threshold was significantly decreased (p<0.05) at 25, 50 and 100 miles. Conditioned pain modulation was also significantly decreased (p<0.05) at 25, 50 and 100 miles of an ultra-marathon competition. Conclusions Together these data suggest an increased peripheral and/or central pain sensitization starting at 25 miles and continuing throughout an ultra-marathon competition run in these conditions. This is the first study that provides evidence of a decreased peripheral pain threshold and decreased central pain inhibition from ultra-marathon running. Decreases in both the peripheral pain threshold and central inhibition may result from nociceptor plasticity, central sensitization or a combination of both. Implications Based on previous research that has indicated a central sensitization resulting from inflammation and the well-documented inflammatory response to the rigors of ultra-marathon competition, we suggest the decreased peripheral pain threshold and decreased descending pain inhibition results from this inflammatory response of running an ultra-marathon.

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Wang, Hui-Yun, Jie Feng, Xu-Dong Wang, Yang Wen, Jiu-Yan Wei, Huan-Fei Wen, Yun-Bo Shi, Zong-Min Ma, Yan-Jun Li und Jun Liu. „Measurement of local contact potential difference of atomic scale Au/Si(111)-(7×7) delocalized adsorption state in room-temperature and ultra-high vacuum environment“. Acta Physica Sinica 71, Nr. 6 (2022): 060702. http://dx.doi.org/10.7498/aps.71.20211853.

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The structural properties and local contact potential difference of Au on Si(111)-(7×7) surface are studied by the homemade ultra-high vacuum non-contact Kelvin probe force microscope. Although scanning tunneling microscopy has been widely used to study the metal- adsorbed semiconductor surfaces on an atomic scale, the tunnel current measured by scanning tunneling microscopy is easy to lead the charge states to accidentally switch in the measurement process, and it is limited only to the observation of metal and semiconductor surfaces. Kelvin probe force microscope allows us to directly measure the charges at different positions of various flat surfaces by local contact potential difference on an atomic scale, which has become a more convenient and accurate means of charge characterization. In this paper, the topography and local contact potential difference of Au adsorbed Si(111)-(7×7) surface are measured on an atomic scale by Kelvin probe force microscope at room temperature, and the corresponding adsorption model and first principle calculation are established. The differential charge density distribution of the stable adsorption position of Au/Si(111)-(7×7) is obtained, and the local contact potential energy difference relationship of the stable adsorption position of Au on Si surface is given, The mechanism of charge transfer between Au atom and Si(111)-(7×7) surface during adsorption is analyzed. The experimental results show that at room temperature, single Au atom will form triangular delocalized adsorption state in the half unit cell of Si(111)-(7×7). The delocalized adsorption state is due to the fact that the moving speed of a single Au atom in the HUC is faster than the scanning speed of Kelvin probe force microscope, and the local contact potential difference measurement of Au/Si(111)-(7×7) adsorbed surface can effectively identify Au and Si atoms. Obviously, this research is of great significance in promoting the development of surface charge precision measurement, and is expected to provide some insights into the charge properties of metal adsorbed semiconductor surfaces.

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Xu, J., M. J. Cox und M. J. Kim. „Chemically Clean Planar Interface Synthesis: Substrate Surface and Interface Cross Section Microscopy“. Microscopy and Microanalysis 3, S2 (August 1997): 635–36. http://dx.doi.org/10.1017/s1431927600010060.

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An ultra high vacuum (UHV) planar interface unit has been constructed to study the effect of interface/boundary structure and chemistry on properties. We report here initial observations of substrate morphology and chemistry prior to bonding and resulting interface morphology obtained using austenitic stainless steel.To synthesize chemically clean planar interfaces by diffusion bonding, the substrate must be macroscopically and microscopically flat and chemically clean. Macro-flatness, necessary for bonding to occur over large areas, was ensured by conventional mechanical polishing and lapping. Substrate surfaces were cleaned by a broad (3cm) 500 eV ion beam (Ar or Xe) at 15° incidence. The resulting changes in substrate near-atomic-scale roughness and chemistry were analyzed using Auger spectroscopy (AES) and Atomic Force Microscopy (AFM). Before ion beam cleaning, the sub-strates exhibited high oxygen and carbon contamination (Fig la). Both Xe and Ar ion cleaning reduced these values; the result for 5 minutes Ar cleaning is shown in Fig lb.

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Cheng, Zhou, Haicheng Shao, Shahid Hussain, Hassan Fouad, M. S. Akhtar und Guanjun Qiao. „Preparation and Properties of MAX Phase High-Temperature Antioxidant Coatings on C/C Composite Surfaces by Ultra-High Speed Laser Cladding“. Science of Advanced Materials 15, Nr. 2 (01.02.2023): 199–208. http://dx.doi.org/10.1166/sam.2023.4429.

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Prefabricated MAX (Ti3SiC2, Ti3AlC2) phase coating materials with coefficient of thermal expansion Si and SiC as transition layers and excellent high-temperature antioxidant properties were used for ultra-high-speed laser melting on the surface of carbon/carbon composites, so that the produced coatings have good interfacial bonding and high-temperature antioxidant properties. In this study, we characterised and analysed the microscopic morphology and composition of the sample coatings using X-ray diffraction and scanning electron microscopy, investigated their interfacial bonding properties by scratch tests and studied the high temperature oxidation resistance of the samples at 1773 K for 1 h. The results show that the bonding strength between the coating and the substrate is good, the surface is flat without flaking, the coating thickness can be controlled below 60 μm, the microstructure is dense, and there is no obvious deformation or failure of the substrate, and the dense coating formed by laser melting has strong oxidation resistance, so that the substrate carbon/carbon composite is well protected at high temperature.

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Volkov, Оleg, Valeria Subbotinа und Anna Fedorenko. „Development of a technological complex for thermofriction hardening of products with a circular cross section“. Bulletin of Kharkov National Automobile and Highway University, Nr. 94 (16.12.2021): 65. http://dx.doi.org/10.30977/bul.2219-5548.2021.94.0.65.

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There are many methods of influencing the structural state of the surface of products of different shapes and different purposes. At the same time, the increase in the relevance of the application of a particular method is closely related to its ability to provide high hardening rates while reducing the cost of such products. The TFН technology has already shown its high efficiency in strengthening surfaces [1]. In addition, studies were conducted on the hardening of surfaces of different profiles [2]. However, the best results are achieved when hardening flat surfaces. In this regard, it is entirely appropriate to conduct research that is related to the development of a technological complex that would include the optimal ratio of processing factors to ensure the necessary level of hardening in the studied objects that have a circular cross-section. Goal. The purpose of this work is to develop a technological complex for processing objects with a circular cross-section. To achieve this goal, metallographic and durometric studies of samples in the initial state and after processing were carried out. At the same time, the changes in the structure and mechanical properties that occur in steel due to processing were studied. Method. The method of thermal friction hardening includes a combined effect of heat and deformation on the treated surface. The peculiarity of this method is the deformation under short-term heating conditions. This makes it possible to further strengthen pre-hardened materials. Results. Under the influence of TFC, significant changes are observed in the structure of cylindrical samples made of 65G steel. This is expressed by the formation of a so-called "white surface layer" in the surface of these samples, which has an ultra-high microhardness [13, 14]. The properties of this layer depend on the initial state of the material, the conditions and modes of conducting TFН.

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Ibrahim, Ihab M., Dina W. Elkassas und Mai M. Yousry. „Effect of EDTA and Phosphoric Acid Pretreatment on the Bonding Effectiveness of Self-Etch Adhesives to Ground Enamel“. European Journal of Dentistry 04, Nr. 04 (Oktober 2010): 418–28. http://dx.doi.org/10.1055/s-0039-1697862.

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Objectives: This in vitro study determined the effect of enamel pretreatment with phosphoric acid and ethylenediaminetetraacetic acid (EDTA) on the bond strength of strong, intermediary strong, and mild self-etching adhesive systems.Methods: Ninety sound human premolars were used. Resin composite cylinders were bonded to flat ground enamel surfaces using three self-etching adhesive systems: strong Adper Prompt L-Pop (pH=0.9–1.0), intermediary strong AdheSE (pH=1.6–1.7), and mild Frog (pH=2). Adhesive systems were applied either according to manufacturer instructions (control) or after pretreatment with either phosphoric acid or EDTA (n=10). After 24 hours, shear bond strength was tested using a universal testing machine at a cross-head speed of 0.5 mm/minute. Ultra-morphological characterization of the surface topography and resin/enamel interfaces as well as representative fractured enamel specimens were examined using scanning electron microscopy (SEM).Results: Neither surface pretreatment statistically increased the mean shear bond strength values of either the strong or the intermediary strong self-etching adhesive systems. However, phosphoric acid pretreatment significantly increased the mean shear bond strength values of the mild self-etching adhesive system. SEM examination of enamel surface topography showed that phosphoric acid pretreatment deepened the same etching pattern of the strong and intermediary strong adhesive systems but converted the irregular etching pattern of the mild self-etching adhesive system to a regular etching pattern. SEM examination of the resin/enamel interface revealed that deepening of the etching pattern was consistent with increase in the length of resin tags. EDTA pretreatment had a negligible effect on ultra-morphological features.Conclusions: Use of phosphoric acid pretreatment can be beneficial with mild self-etching adhesive systems for bonding to enamel. (Eur J Dent 2010;4:418-428)

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Wen, Rui, Abhishek Lahiri, Mukkannan Alagurajan, Akiyoshi Kuzume, Shin-ichiro Kobayashi und Kingo Itaya. „Preparation and characterization of ultra-flat single crystal surfaces of Pd(111) and Au(111) by an in situ interference optical microscopy“. Journal of Electroanalytical Chemistry 649, Nr. 1-2 (November 2010): 257–60. http://dx.doi.org/10.1016/j.jelechem.2010.06.009.

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Hasan, Mohammad Nasim, SM Shavik, KF Rabbi, KM Mukut und AKMM Morshed. „Phase Change Characteristics of Ultra-Thin Liquid Argon Film over different Flat Substrates at High Wall Superheat for Hydrophilic/Hydrophobic Wetting Condition: A Non-Equilibrium Molecular Dynamics Study“. Journal of Chemical Engineering 29, Nr. 1 (31.08.2017): 49–55. http://dx.doi.org/10.3329/jce.v29i1.33820.

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Non-equilibrium molecular dynamics simulations have been conducted to understand the effect of solid-liquid interfacial wettability and surface material on the phase change phenomena of the thin liquid argon film placed over flat substrate at high wall superheat. The molecular system consists of a three phase simulation domain involving solid wall, liquid argon and argon vapor. After the system is thermally equilibrated at 90K and kept in equilibrium for a while, a high wall superheat (250K that is far above the critical temperature of argon) is induced at the liquid boundary so that the liquid undergoes ultrafast heating. Both hydrophilic and hydrophobic surfaces were considered in the present study in order to observe the effect of surface wettability on phase change characteristics for three different solid substrate materials namely, Platinum (Pt), Silver (Ag) and Aluminium (Al). Results obtained in the present study are discussed in terms of transient atomic distribution inside system domain, heat flux characteristics across the solid-liquid interface together with evaporative mass flux from liquid argon. Simulation results show that, depending on the surface wetting condition, the phase change process appears to be very different (explosive/ diffusive) for all three substrate materials under consideration. Among three materials considered herein, Al is found to offer the least favourable condition for phase change process while Pt and Ag show similar heat and mass transfer characteristics for both hydrophilic and hydrophobic wetting conditions. Surface wettability effect is found to be more prominent than the effect of substrate material in thin film liquid phase change phenomena.Journal of Chemical Engineering, Vol. 29, No. 1, 2017: 49-55

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Nur-E-Alam, Mohammad, Mikhail Vasiliev und Kamal Alameh. „Bi-Substituted Ferrite Garnet Type Magneto-Optic Materials Studied at ESRI Nano-Fabrication Laboratories, ECU, Australia“. Coatings 12, Nr. 10 (05.10.2022): 1471. http://dx.doi.org/10.3390/coatings12101471.

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Since 2007, at the Electron Science Research Institute (ESRI) nano-fabrication laboratories, Edith Cowan University, Australia, we have devoted research efforts to the synthesis and characterization of bismuth-containing ferrite-garnet-type thin-film magneto-optic (MO) materials of different compositions. We report on the growth and characteristics of radio frequency (RF) magnetron sputtered bismuth-substituted iron-garnet thin films. We study the process parameters associated with the RF magnetron sputter deposition technique and investigate the results of optimizing process parameters. To achieve the best MO properties, we employ a few unique techniques, such as co-sputtered nanocomposite films and all-garnet multilayer structures, as well as the application of oxygen plasma treatment to amorphous garnet layers immediately following the deposition process. We demonstrated a remarkable enhancement in the MO properties of Bi-containing ferrite-type garnet thin-film materials, including record-high MO figures of merit and improved conventional and unconventional hysteresis loops of Faraday rotation. Previously unpublished research results on the forward-looking applications of magnetic garnet coatings applied to microparticles of advanced luminescent materials are reported. In the context of developing the next-generation ultra-fast optoelectronic devices, such as light intensity switches and modulators, high-speed flat panel displays, and high-sensitivity sensors, it is important to consider the desirable optical, magnetic, and magneto-optic properties that are found in highly bismuth-substituted iron garnet thin-film materials of various composition types.

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Gevaert, Matthew R., Martine LaBerge, Jennifer M. Gordon und John D. DesJardins. „The Quantification of Physiologically Relevant Cross-Shear Wear Phenomena on Orthopaedic Bearing Materials Using the MAX-Shear Wear Testing System“. Journal of Tribology 127, Nr. 4 (01.06.2005): 740–49. http://dx.doi.org/10.1115/1.2000272.

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Background: The occurrence of multi-directional sliding motion between total knee replacement bearing surfaces is theorized to be a primary wear and failure mechanism of ultra-high molecular weight poly(ethylene) (UHMWPE). To better quantify the tribologic mechanisms of this cross-shear wear, the MAX-Shear wear-testing system was developed to evaluate candidate biomaterials under controlled conditions of cross-shear wear. Method of approach: A computer controlled traveling x-y stage under a 3 degree-of-freedom statically loaded pin is used to implement the complex multi-directional motion pathways observed during TKR wear simulation. A MHz collection of dynamic x-y friction was available on all six environmentally controlled stations. The functionality of this testing platform was proven in a 100,000 cycle, 11.6 MPa, wear test using 15.0 mm diameter polished stainless steel spheres against flat GUR4150 UHMWPE. A five-pointed star wear pattern was used to incorporate the physiologically relevant cross-shear sliding conditions of stop/start, 50mm∕s entraining velocity and five crossing angles of 72°. Using normalized volumetric reconstruction of the resulting surface damage, a direct quantitative relationship between linear and cross-shear surface damage intensity was obtained. Results: Cross-shear surface damage volume loss was found to be 2.94 (±0.88) times that associated with linear sliding under identical tribologic conditions. SEM analysis of linear wear damage showed consistent fibril orientation along the direction of sliding while cross-shear wear damage showed multi-directional fibril orientations and increased surface roughness. Significant increases in discrete crossing-point friction coefficients were recorded throughout testing. Conclusions: This scientific approach to quantifying the tribologic effects of cross-shear provides fundamental wear mechanism data that are critical in evaluating potential biomaterials for use as in vivo bearings. Relevant multi-axis, cross-shear wear testing is necessary to provide quantifiable measures of complex biomaterials wear phenomena.

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