Artículos de revistas: "Flattened surface"

1

Evans, Richard B. "The flattened surface parabolic equation". Journal of the Acoustical Society of America 104, n.º 4 (octubre de 1998): 2167–73. http://dx.doi.org/10.1121/1.423729.

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2

Hui, Chung-Yuen, Zezhou Liu, Nicolas Bain, Anand Jagota, Eric R. Dufresne, Robert W. Style, Ryuji Kiyama y Jian Ping Gong. "How surface stress transforms surface profiles and adhesion of rough elastic bodies". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 476, n.º 2243 (noviembre de 2020): 20200477. http://dx.doi.org/10.1098/rspa.2020.0477.

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The surface of soft solids carries a surface stress that tends to flatten surface profiles. For example, surface features on a soft solid, fabricated by moulding against a stiff-patterned substrate, tend to flatten upon removal from the mould. In this work, we derive a transfer function in an explicit form that, given any initial surface profile, shows how to compute the shape of the corresponding flattened profile. We provide analytical results for several applications including flattening of one-dimensional and two-dimensional periodic structures, qualitative changes to the surface roughness spectrum, and how that strongly influences adhesion.

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3

Harada, Takeshi y Takuya Semba. "A Truing Technique of Flattening Diamond Grains for Fabricating Microstructures with Fine Surfaces". Key Engineering Materials 389-390 (septiembre de 2008): 350–55. http://dx.doi.org/10.4028/www.scientific.net/kem.389-390.350.

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A truing technique that can be used to shape the tip of an electroformed diamond tool into a hemisphere and flatten diamond grains on the tool working surface at the same level as the bond face was developed. A polycrystalline diamond disk whose top surface roughened by electrical discharge machining was partially flattened by grinding was used as a truer. Diamond grains on the tool working surface were successfully flattened along the hemispherical tool profile when the grains mesh size of #1000 was employed. In addition, a grinding test using glasslike carbon as a work material revealed that a surface roughness of less than 50 nm Rz could be obtained in both cases when moving the tool on contour and scanning paths.

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4

Wandell, Brian A., Suelika Chial y Benjamin T. Backus. "Visualization and Measurement of the Cortical Surface". Journal of Cognitive Neuroscience 12, n.º 5 (septiembre de 2000): 739–52. http://dx.doi.org/10.1162/089892900562561.

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Much of the human cortical surface is obscured from view by the complex pattern of folds, making the spatial relationship between different surface locations hard to interpret. Methods for viewing large portions of the brain's surface in a single flattened representation are described. The flattened representation preserves several key spatial relationships between regions on the cortical surface. The principles used in the implementations and evaluations of these implementations using artificial test surfaces are provided. Results of applying the methods to structural magnetic resonance measurements of the human brain are also shown. The implementation details are available in the source code, which is freely available on the Internet.

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5

Sun, Bo, Ji Qing Wang, Zheng Liu y Hua Chen. "Research of Surface Flattening Method Based on Triangle and Energy Model". Advanced Materials Research 411 (noviembre de 2011): 112–16. http://dx.doi.org/10.4028/www.scientific.net/amr.411.112.

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In order to acquire reasonable blank shape of sheet metals with complex surface, surface flattening method based on triangle and energy model is put forward. According to equal surface principle, the surface is divided into many triangles, which are flattened one after another. Meanwhile, the surface is regarded as energy model, which is used to alter original flattened discrete points. Finally, surface approximate flattening is completed with second development technology based on Pro/ENGINEER platform. In sheet metal manufacturing process, reasonable blank shape is generated quickly.

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6

Chen, Jun, She Wei Xin, Wei Zhou, Qian Li, Si Yuan Zhang, Lei Li, Hai Ying Yang y Ting Xun Wang. "Stress Analysis and Microstructure Evolution of Titanium Alloy Pipe during Flattening Processing". Materials Science Forum 944 (enero de 2019): 1088–93. http://dx.doi.org/10.4028/www.scientific.net/msf.944.1088.

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TA24 titanium alloy pipe with 638mm diameter and 19mm wall thickness is carried out continuous load flatten test, and the stress of internal and external pipe wall during flatten process is studied in this paper. The results show that the TA24 titanium alloy tube has good flattening performance, and the flattening process has experienced original stage, flattened oblate stage, flattened straight wall stage, flattened depressed stage, flattened concave contact stage. During the flattening process, the outer layer of the upper and lower wall of the tube is subjected to compressive stress, and the inner layer material is subjected to tensile stress. The tensile and compressive forces cause the vertical part of the upper and lower walls to be concave. The outer layer of the left and right circular arc parts is subjected to tensile stress and the inner layer is subjected to tensile stress. The compressive stress also causes the radius of the arc to decrease due to the combined force of the tensile and compressive forces, that is, the flattening occurs. With the decrease of and pressing distance under continuous loading condition, the metal on the left and right sides of the pipe gathers toward the middle depression, which aggravates the deformation of the upper and lower walls until the upper and lower walls contact, and the arc radius of the left and right walls decreases until the outer surface cracks. The pipe microstructure changes significantly into elongated deformation structure during the flattening process. The most severe part of the deformation is the left and right end arc of the pipe, followed by the upper and lower end depression.

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7

Ho, P. T. P., Y.-L. Peng, J. M. Torrelles, J. F. Gómez, L. F. Rodríguez y J. Cantó. "A Flattened Cloud Core in NGC 2024". International Astronomical Union Colloquium 140 (1994): 262–63. http://dx.doi.org/10.1017/s0252921100019710.

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With the VLA in the D configuration we have mapped the (J,K) = (1,1) and (2,2) NH3 lines toward a molecular cloud core in NGC 2024. This region, which contains one of the most highly collimated molecular outflows (Richer et al. 1992), has been studied extensively using a variety of techniques, including dust continuum in the far-infrared (FIR) wavelengths (Mezger et al. 1988, 1992), and molecular lines (see Barnes & Crutcher 1992 and references therein). We find that the molecular condensations associated with FIR 5, 6, and 7 (Mezger et al. 1988, 1992) have kinetic temperatures TK ≃ 40 K. We also find a perturbation of the molecular gas near FIR 6 and FIR 7 in terms of broadening of the ammonia lines. These results suggest that these condensations may not be protostars heated by gravitational energy released during collapse, but that they have an internal heating source. A flattened structure of ammonia emission is found extending parallel to the unipolar CO outflow structure, but displaced systematically to the east. The location of the high velocity outflow along the surface of the NH3 structure suggests that a wind is sweeping material from the surface of this elongated cloud core. Figure 1 is an overlay of the VLA ammonia emission (dotted area) on top of the C18O emission (thick contours) and the CO outflow (thin contours).

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8

Zhao, Zi Yu, Bi Bo Xia, Su Zhi Zhang y Li Wang. "Simulation Analysis of Splat Deposition in Plasma Spray Forming". Advanced Materials Research 291-294 (julio de 2011): 505–8. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.505.

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Splat deposition is an important part influencing coating quality in plasma spray forming. Flatten behavior of a single Ni droplet falling on a smooth substrate is evaluated by numerical simulation of ANSYS software, this paper meanwhile researches a single Ni particle deposition in the surface of flattened Al2O3 sheet and thin Al particles, the impact factors of particles flattening and the mechanism of the interaction between particles are also studied. The results have benefit to improving the coating porosity and bond strength between particles.

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9

Sigamani, Ashokkumar, Arunai Nambiraj, Girigesh Yadav, Ananda Giribabu, Karthikeyan Srinivasan, Venkadamanickam Gurusamy, Kothanda Raman, Kaviarasu Karunakaran y Rajesh Thiyagarajan. "Surface dose measurements and comparison of unflattened and flattened photon beams". Journal of Medical Physics 41, n.º 2 (2016): 85. http://dx.doi.org/10.4103/0971-6203.181648.

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10

Sun, Bo y Xiao Long Wang. "Unfolding Method of Non-Developable Surface for Sheet-Metal Design". Advanced Materials Research 1022 (agosto de 2014): 60–63. http://dx.doi.org/10.4028/www.scientific.net/amr.1022.60.

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The organized vertex coordination of the triangular surfaces is obtained by the meshing method in the 3D kernel based developing environment. To optimize the flattened form, the energy method is used to find the reasonable unfolding scheme, which seeks the solution to minimize the deforming energy generated when flattening the triangular surfaces. This algorithm is not the fastest one, but the versatile one especially for the non-developable surface with a large bending degree. With the unfolding method and the 3D kernel environment, the 3D unfolding system for the arbitrary surface satisfying the requirements is constructed.

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11

Fang, Jing Jing y Yu Ding. "Energy-Based Optimum Pattern Development for Garment Industry". Advanced Materials Research 201-203 (febrero de 2011): 1223–32. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.1223.

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Distortions are inevitable when flattening is applied to an irregular surface. This study presents a meshing energy model and evaluates the energy variation between the 3D designed surface and the 2D flattened pattern in order to minimize the energy that arises from the development process. Base on expert knowledge, constraint optimization methods are used to find the unique pattern in its minimum deformation. This method is applied via simulation to some garment examples. Taking design and manufacturing conditions into consideration, the designed garments are flattened into patterns which have the least energy and area variation from the 3D designs.

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12

Makris, Nikos, Steven M. Hodge, Christian Haselgrove, David N. Kennedy, Anders Dale, Bruce Fischl, Bruce R. Rosen, Gordon Harris, Verne S. Caviness y Jeremy D. Schmahmann. "Human Cerebellum: Surface-Assisted Cortical Parcellation and Volumetry with Magnetic Resonance Imaging". Journal of Cognitive Neuroscience 15, n.º 4 (1 de mayo de 2003): 584–99. http://dx.doi.org/10.1162/089892903321662967.

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We describe a system of surface-assisted parcellation (SAP) of the human cerebellar cortex derived from neural systems functional and behavioral anatomy. This system is based on MRI and preserves the unique morphologic and topographic features of the individual cerebellum. All major fissures of the cerebellum were identified and traced in the flattened representation of the cerebellar cortex using the program “Free Surfer.” Parcellation of the cerebellar cortex followed using the fissure information in conjunction with landmarks using the program “Cardviews” to create 64 gyral-based cerebellar parcellation units. Computer-assisted algorithms enable the execution of the cerebellar parcellation procedure as well as volumetric measurements and topographic localization. The SAP technique makes it possible to represent multimodal structural and functional imaging data on the flattened surface of the cerebellar cortex as illustrated in one functional MRI experiment.

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13

Murashov, Mikhail V. "A Condition for Complete Flattening of Asperities in a Rough Contact". MATEC Web of Conferences 220 (2018): 01007. http://dx.doi.org/10.1051/matecconf/201822001007.

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Considering rough surface profiles in a contact model is of decisive importance. In the up-to-date rough contact models there remained underexplored the opportunity of complete flattening of smaller asperities and therefore the need of using the multilevel roughness models, including fractal ones. If higher level asperities are not flattened completely when pressed, then they will be able to impact on the contact process. This paper considers model problems of elastic-plastic contact with hardening for a body with protrusions and two pyramids as the objects similar to asperities. Modeling results show that asperities are completely flattened only on condition of confined compression. For real contacting rough surfaces under low pressures, complete flattening of asperities will not occur. It is shown that roughness elements on the surface of the asperities do not disappear even at severe deformation of the latter. The reason is a combination of the asperity form and hardening of material, while the consequence is a reduction of the real contact area.

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14

Augulis, R., R. Valiokas, B. Liedberg y R. Rotomskis. "Atomic Force Microscopy of Self-Assembled Nanostructures of TPPS₄ on SAM Substrates". Solid State Phenomena 97-98 (abril de 2004): 195–200. http://dx.doi.org/10.4028/www.scientific.net/ssp.97-98.195.

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The adsorption of organic molecules on solid surfaces is one of the fundamental processes for the development of molecular-based nanodevices. Here we focus on the adsorption and ordering of the TPPS4-based J-aggregates on silicon and gold as well as on self-assembled monolayer (SAM) surfaces. The SAMs used for the experiments were based on the chemisorption of thiol containing compounds onto gold. Long ω-substituted alkanethiols are spontaneously assembled on gold to form highly ordered and densely packed layers with controllable chemical and physical properties. TPPS4 J-aggregates were dispersed on SAM surfaces, and on plain gold and silicon substrates for comparison. The dimensions of aggregates, measured by means of atomic force microscopy, varied depending on the type of substrate. Long stripe-like aggregates were flattened on the substrate surface, and the height and width of aggregates highly correlated with the polarity of surface groups. For example, the J-aggregates were narrower on hydrophobic substrates (with non-polar groups) and wider on hydrophilic substrates (with polar groups). These observations support the hypothesis, that TPPS4 forms .soft. cylindrical aggregates, that appear flattened on the substrate.

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15

Gies, D. R. "O and B-star surface mapping". Symposium - International Astronomical Union 176 (1996): 121–28. http://dx.doi.org/10.1017/s0074180900083157.

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The massive O and B-type stars will be among the first targets of the new generation of long baseline optical interferometers (such as the CHARA Array, a 400-m diameter distributed array of five 1-m telescopes). Many of these objects are binary stars for which joint astrometric and spectroscopic observations will provide masses and distances (e.g., 15 Mon; Gies et al. 1993), but there is also great interest in resolving disks of single stars. Early interferometric observations have already resolved the flattened circumstellar disks around some Be stars (Quirrenbach et al. 1994).

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16

Yanagisawa, T., S. Takuma y O. Fejerskov. "Ultrastructure and Composition of Enamel in Human Dental Fluorosis". Advances in Dental Research 3, n.º 2 (septiembre de 1989): 203–10. http://dx.doi.org/10.1177/08959374890030022101.

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Materials used in this work were 13 permanent molars exhibiting dental fluorosis (between 5 and 9 on the Thylstrup-Fejerskov scale, 1978) obtained from adults (aged 20-40 years) living in regions with 3.5 ppm fluoride in the water supplies. Small but deep occlusal caries lesions necessitated extraction. Light and polarized microscopic, microradiographic, electron microscopic, and electron-probe- and ion-micro-analytical studies were made. Enamel surfaces were generally cloudy to opaque, with several pits or defects of various sizes and degrees of brown-staining. An extensively hypomineralized area extended from the inner enamel to the surface layer, which was mineralized to a high degree. The hypomineralized area contained sparsely arranged, flattened, hexagonal crystals with either perforated centers or defects extending from the perimeter and indicating either no or low fluoride content. The highly mineralized surface layer, however, was composed of many large, flattened, hexagonal crystals and extremely small, irregularly shaped crystals. Both types were free of central perforations and defects. A high fluoride concentration was determined in the highly mineralized surface layer. These findings suggest that the hypomineralized area undergoes caries-like changes in terms of crystal dissolution and that the highly mineralized surface layer contains hydroxyapatite and fluoridated-hydroxyapatite, or fluorapatite, or both.

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17

Ai, Xiaolan y Herbert S. Cheng. "A Transient EHL Analysis for Line Contacts With Measured Surface Roughness Using Multigrid Technique". Journal of Tribology 116, n.º 3 (1 de julio de 1994): 549–56. http://dx.doi.org/10.1115/1.2928879.

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Transient EHL analysis for line contacts with measured surface roughness is performed by using the multigrid method. Results show that the transient effect, induced by surface roughness, has a remarkable influence on pressure distribution and the film thickness profile. Pressure fluctuation increases with the relative sliding speed between the contact surfaces. For simple sliding with stationary surface roughness, the roughness profile is almost flattened. When the rough surface moves, the elastically deformed surface roughness, in the contact zone, increases with the moving speed. As the moving speed of surface roughness equals to or exceeds the rolling speed, the roughness of the deformed surface profile in the contact zone is close to the roughness of the undeformed roughness profile.

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18

Hooke, C. J. "The behaviour of heavily loaded line contacts with transverse roughness". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 213, n.º 4 (1 de abril de 1999): 309–20. http://dx.doi.org/10.1243/0954406991522275.

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In heavily loaded, piezoviscous contacts the surface roughness tends to be flattened inside the conjunction by any relative sliding of the surfaces. However, before it is flattened, the roughness affects the inlet to the contact, producing clearance variations there. These variations are then convected through the contact, at the entrainment velocity, producing a clearance distribution that differs from the original surface. The present paper explores this behaviour and establishes how the amplitude of the convected clearance varies with wavelength and operating conditions. It is shown that the primary influence is the ratio of the wavelength to the inlet length of the conjunction. Where this ratio is large, the roughness is smoothed and there is little variation in clearance under the conjunction. Where the ratio is small, significant variations in clearance may occur but the precise amplitude and phasing depend on the ratio of slide to roll velocities and on the value of a piezoviscous parameter, c. The numerical results agree closely with existing solutions but extend these to cover the full range of operating conditions.

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19

Oh, Seung-Won, Jong-Min Baek, Jun-Hee Park y Tae-Hoon Yoon. "Surface flattening of a polyimide layer in a liquid crystal cell fabricated by using a field-induced UV-alignment method". RSC Advances 6, n.º 60 (2016): 55282–85. http://dx.doi.org/10.1039/c6ra07634c.

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20

Gupta, Abhik, Sudip Dey y Suswita Gupta. "Cuticular sensory structures on the legs of Orthetrum sabina (Odonata: Libellulidae) as revealed by SEM". Proceedings, annual meeting, Electron Microscopy Society of America 48, n.º 3 (12 de agosto de 1990): 486–87. http://dx.doi.org/10.1017/s0424820100159977.

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Occurrence and distribution of various cuticular sensory structures such as Sensilla chaetica, S. trichoidea, S. basiconica, pore sensilla, hairplates, S. campanifonuia, microtrichial structures, as well as unique hemispherical protuberances and flattened branched setae are presented. Their morphology is described, and size ranges recorded.As seen in figures 1 and 2, the coxa has two hairplate like structures, each comprising a group of trichoid sensilla with blunt and slightly bulbous tips. The femur has minute basiconic pegs, and pores as well, scattered on its surface(figure - 3 ). The tibial surface shows a profusion of unique flattened and branched setae (figure - 4 ). Similar setae are also present along the outer margin of the tarsus (figure - 5) which also bears a number of hemispherical protuberances(figure - 6 ).

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21

Song, Xiao Zong y Fei Hu Zhang. "Research on the Characterization of Ultra-Smooth K9 Glass Surface Polished by Nanoparticle Colloid Jet Machining". Key Engineering Materials 609-610 (abril de 2014): 552–56. http://dx.doi.org/10.4028/www.scientific.net/kem.609-610.552.

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In this work, optical K9 glass surface has been flattened by nanoparticle colloid jet machining, which is an ultra-smooth surface processing technique utilizing surface chemical effect between work surface atoms and nanoparticles in alkaline colloid to remove the uppermost surface atoms. The surface removal process of nanoparticle colloid jet machining has been investigated through K9 glass polish experiments. And the characterizations of ultra-smooth K9 glass surface polished by nanoparticle colloid jet machining have also been studied in this paper. Surface profiler and atomic force microscopy (AFM) are used to observe the surface microscopic morphological characteristics of K9 glass sample before and after polishing by nanoparticle colloid jet machining. The measurement results of processed surface prove that the primary scratches on the original surface have been completely wiped off by nanoparticle colloid jet machining and the roughness of the K9 glass surface has been improved to be less than 1 nm (Rq). Autocovariance (ACF) is investigated along a cross section of the K9 glass surface to determine the dominant spatial frequencies. The ACF curves show that the surface morphology of K9 glass processed by nanoparticle colloid jet machining is completely different from the preprocessed surface. The final K9 glass surface has been flattened by nanoparticle colloid jet machining. The microscopic morphological profile of the final K9 glass surface becomes increasingly smooth and eventually close to a flat state.

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22

Argenzio, R. A., C. K. Henrikson y J. A. Liacos. "Restitution of barrier and transport function of porcine colon after acute mucosal injury". American Journal of Physiology-Gastrointestinal and Liver Physiology 255, n.º 1 (1 de julio de 1988): G62—G71. http://dx.doi.org/10.1152/ajpgi.1988.255.1.g62.

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Acute injury of the porcine colonic epithelium was induced in vivo with the bile salt, deoxycholate. A concentration of 15 mM for 30 min completely destroyed the surface epithelium and induced a marked increase in mucosal permeability to mannitol. The crypt epithelium however was not significantly affected. Within 8 min of recovery, the colonic surface was reepithelialized with flattened, migrating cells, and within 40 min, mucosal permeability to mannitol was normalized. In vitro studies showed that in these early stages of recovery, NaCl transport, short-circuit current, and resistance were markedly impaired, whereas the theophylline-induced secretory response remained intact. Recovery of absorptive function paralleled the transition from flattened to columnar surface epithelium and was complete within 2 h. Results suggest that 1) active migratory events play an important role in rapid restitution of an epithelial barrier, 2) active absorption of ions is much slower to recover, and 3) active secretory events are intact and probably originate in the crypt epithelium.

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23

Roberts, Rhiannon y Maurice Hallett. "Neutrophil Cell Shape Change: Mechanism and Signalling during Cell Spreading and Phagocytosis". International Journal of Molecular Sciences 20, n.º 6 (19 de marzo de 2019): 1383. http://dx.doi.org/10.3390/ijms20061383.

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Perhaps the most important feature of neutrophils is their ability to rapidly change shape. In the bloodstream, the neutrophils circulate as almost spherical cells, with the ability to deform in order to pass along narrower capillaries. Upon receiving the signal to extravasate, they are able to transform their morphology and flatten onto the endothelium surface. This transition, from a spherical to a flattened morphology, is the first key step which neutrophils undergo before moving out of the blood and into the extravascular tissue space. Once they have migrated through tissues towards sites of infection, neutrophils carry out their primary role—killing infecting microbes by performing phagocytosis and producing toxic reactive oxygen species within the microbe-containing phagosome. Phagocytosis involves the second key morphology change that neutrophils undergo, with the formation of pseudopodia which capture the microbe within an internal vesicle. Both the spherical to flattened stage and the phagocytic capture stage are rapid, each being completed within 100 s. Knowing how these rapid cell shape changes occur in neutrophils is thus fundamental to understanding neutrophil behaviour. This article will discuss advances in our current knowledge of this process, and also identify an important regulated molecular event which may represent an important target for anti-inflammatory therapy.

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24

Lee, H., J. W. Park, Byung Ju Choi, S. I. Yeo y Jo Young Suh. "The Effects of the Various Surface Treatments of Titanium on Cellular Activity of Osteoblast-Like Cells". Key Engineering Materials 330-332 (febrero de 2007): 71–74. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.71.

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The response of osteoblast-like cells cultured on blasted and/or acid etching surfaces and the influence of surface texture or microtopography on cell attachment, cell proliferation, and the gene expression of the osteoblastic phenotype using ROS 17/2.8 cell lines were evaluated. The blasted and/or acid etching surfaces were significantly rougher in comparison to machined and etched surfaces (p < 0.05). On X-ray diffraction analysis, titanium hydride (TiH2) was observed on the surface etched with a mixture of HCl-H2SO4 solution, whereas TiH2 was not observed on machined and blasted surfaces. After 24 h incubation, most of the cells of all the groups had a flattened, polygonal shape and were fully spread, exhibiting the onset of proliferation. The MTT assay showed a significant decrease on the blasted surface compared to the machined surface at 7 day culture (p < 0.05). The expression of osteopontin mRNA, α1 (I) collagen mRNA, and alkaline phosphatase mRNA on rough surfaces was higher than on the machined surfaces, and was highest on the blasted surface at day 7.

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25

Hwang, Joong-Ki, Sung-Jin Kim y Kee-Joo Kim. "Influence of Roll Diameter on Material Deformation and Properties during Wire Flat Rolling". Applied Sciences 11, n.º 18 (9 de septiembre de 2021): 8381. http://dx.doi.org/10.3390/app11188381.

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The influence of roll diameter on the strain distribution, shape change, contact pressure, and damage value of a workpiece was investigated during wire flat rolling to control the material properties of the flattened wire. The flattened wires fabricated by the four different rolls were compared using finite element analysis. The strain inhomogeneity of the flat-rolled wire increased with the roll diameter; thus, the macroscopic shear bands were strengthened as the roll diameter increased during wire flat rolling. The contact width and lateral spreading of the flattened wire increased with the roll diameter; therefore, the reduction in area decreased with the roll diameter. The contour of the normal contact pressure on the wire surface exhibited a similar pattern regardless of the roll diameter. The contact pressure showed higher values at the entry, edge, and exit zones in the contact area. The distribution of the damage value varied with the roll diameter. The free surface region tended to have the peak damage value during the process; however, the center region exhibited the maximum damage value with the roll diameter. From the perspective of the damage value, the optimum roll diameter was in existence during wire flat rolling. The underlying cause of the different strain distributions, shape changes, and damage values of the flat-rolled wire was the different contact lengths originating from the different roll diameters during wire flat rolling.

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26

White, L. R. y S. L. Carnie. "The drag on a flattened bubble moving across a plane substrate". Journal of Fluid Mechanics 696 (1 de marzo de 2012): 345–73. http://dx.doi.org/10.1017/jfm.2012.47.

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AbstractThe equilibrium shape of an axisymmetric liquid drop or gas bubble in an immiscible supporting liquid held under gravity against a horizontal plane rigid surface is derived. A thin film of supporting liquid remains between the drop/bubble surface and the rigid substrate at equilibrium, of thickness ${h}_{0} $ determined by the balance of the disjoining pressure $\Pi (h)$ between the drop and the substrate and the internal Laplace pressure of the drop/bubble. The interface is macroscopically flat around the drop axis out to a radius $a$ but matches smoothly into the outer shape of radius $A$ through a boundary layer region of width $a{ H}_{0}^{1/ 2} $ where ${H}_{0} = 2{h}_{0} A/ {a}^{2} $ is a small parameter. The outer drop shape is determined by a balance of buoyancy forces and local Laplace pressure and is roughly spherical if $A/ \lambda \ll 1$, where $\lambda = \sqrt{\gamma / \mrm{\Delta} \rho g} $ is the capillary length in the interface with a logarithmic correction due to the action of the disjoining pressure across the flattened region. With the shape determined, we calculate the drag force on this flattened bubble to lowest order in the velocity as it moves across the rigid substrate using a lubrication approximation valid to terms of $O( \mathop{ ({h}_{0} / a)}\nolimits ^{2} )$ as an integral over the flattened bubble surface of the hydrodynamic pressure. The lubrication theory of itself is not sufficient to determine the drag due to the divergence of that integral if the outer flow field properties are neglected. By using the known exact result for the drag force on an undistorted bubble, the drag on the flattened bubble can be computed as an integral over the lubrication region alone. We derive the drag as a series expansion in the small parameter ${H}_{0} $ by means of a fairly intricate boundary layer analysis. The logarithmic divergence of the translational drag with film thickness ${h}_{0} $ for the undistorted bubble is replaced by the stronger divergence ${ h}_{0}^{\ensuremath{-} 1/ 2} $ to leading order for the flattened bubble case. We present explicit numerical results for the first few terms in the expansion for the case of an exponentially repulsive disjoining pressure, and analytic expressions for these terms in the limit of very short-range disjoining pressure forces. The results of this calculation are compared with recent work (Hodges, Jensen & Rallison, J. Fluid Mech., vol. 512, 2004, p. 95) where disjoining pressure is neglected and hydrodynamic pressure is balanced against buoyancy and Laplace forces. The limits of validity of this linear drag theory are also presented.

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27

Cashmore, J. "1135 poster SURFACE DOSE CHARACTERISTICS OF 6 AND 10MV FLATTENED AND UNFLATTENED PHOTON BEAMS". Radiotherapy and Oncology 99 (mayo de 2011): S423. http://dx.doi.org/10.1016/s0167-8140(11)71257-9.

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28

Fillmore, James A. y Harold F. Levison. "Dynamical models of highly flattened oblate elliptical galaxies with De Vaucouleurs' surface-brightness profiles". Astronomical Journal 97 (enero de 1989): 57. http://dx.doi.org/10.1086/114956.

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29

HOSOI, A. E. y JOHN W. M. BUSH. "Evaporative instabilities in climbing films". Journal of Fluid Mechanics 442 (24 de agosto de 2001): 217–39. http://dx.doi.org/10.1017/s0022112001005018.

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We consider flow in a thin film generated by partially submerging an inclined rigid plate in a reservoir of ethanol– or methanol–water solution and wetting its surface. Evaporation leads to concentration and surface tension gradients that drive flow up the plate. An experimental study indicates that the climbing film is subject to two distinct instabilities. The first is a convective instability characterized by flattened convection rolls aligned in the direction of flow and accompanied by free-surface deformations; in the meniscus region, this instability gives rise to pronounced ridge structures aligned with the mean flow. The second instability, evident when the plate is nearly vertical, takes the form of transverse surface waves propagating up the plate.We demonstrate that the observed longitudinal rolls are driven by the combined influence of surface deformations and alcohol concentration gradients. Guided by the observation that the rolls are flattened, we develop a quasi-two-dimensional theoretical model for the instability of the film, based on lubrication theory, which includes the effects of gravity, capillarity and Marangoni stresses at the surface. We develop stability criteria for the film which are in qualitative agreement with our experimental observations. Our analysis yields an equation for the shape of the interface which is solved numerically and reproduces the salient features of the observed flows, including the slow lateral drift and merging of the ridges.

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30

Popov, V. "CUTTING PATTERN GENERATION FOR TENT TYPE STRUCTURES REPRESENTED BY MINIMUM SURFACES". Transactions of the Canadian Society for Mechanical Engineering 22, n.º 4A (noviembre de 1998): 369–77. http://dx.doi.org/10.1139/tcsme-1998-0020.

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The paper is a sequel in a set of papers dealing with the development of the Stretched Grid Method (SGM) to minimize surfaces and other related problems. Now we focus on the generation of the cutting patterns for fabric structures with predetermined forms. Based on equi-areal of surface mapping onto the plane area the basic condition results in a formulation of a system of non-linear equations. The simple iteration procedure for cutting patterns generated is used and explained. The efficiency of the approach is demonstrated with examples of surfaces with single and double-curvature that can be simply unfolded or flattened.

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31

Caners, Richard T., Varina Crisfield y Victor J. Lieffers. "Habitat heterogeneity stimulates regeneration of bryophytes and vascular plants on disturbed minerotrophic peatlands". Canadian Journal of Forest Research 49, n.º 3 (marzo de 2019): 281–95. http://dx.doi.org/10.1139/cjfr-2018-0426.

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Wooded rich fens (WRF), characterized by high variation in surface topography and numerous plant species organized along microtopographic gradients, are abundant in continental western Canada. In regions where in situ oil sands exploration (OSE) prevails, however, winter operations eliminate the surface vegetation and mechanically flatten the exposed peat. This results in saturated or flooded soils during the growing season and eliminates plant species dependent on naturally elevated microhabitats, with implications for peatland recovery. In northeastern Alberta, we redeveloped hummock topography on replicate WRF after OSE by extracting blocks of frozen peat from peatland surfaces in the winter. Peat mounds and adjacent unmounded flattened areas were left to regenerate naturally and were sampled four to five summers later. Mounds facilitated the colonization of many peatland plants not adapted to waterlogged soils. For bryophytes, mean richness and diversity of liverworts, Sphagnum, and true mosses were higher in mounded plots than in unmounded plots. For vascular plants, woody plants (trees and shrubs) had higher richness, cover, and diversity (trees only) in mounded plots. Peat mounding may be effective for stimulating vegetation development on OSE-degraded WRF. All mounds, however, will require lateral expansion by hummock-forming mosses to provide the habitat volume required for development of large woody plants.

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32

Sutcliffe, M. P. F. "Flattening of Random Rough Surfaces in Metal-Forming Processes". Journal of Tribology 121, n.º 3 (1 de julio de 1999): 433–40. http://dx.doi.org/10.1115/1.2834086.

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Flattening of random rough surfaces on a workpiece undergoing bulk deformation has beenanalyzed using a model of the surface consisting of just two wavelength components. Asperities are flattened at a rate which depends on the ratio of the initial r.m.s. amplitudes of the long and short wavelength components. The flattening behavior of the long wavelength asperities only becomes important when the amplitude of the long wavelength asperitiesis much greater than that of the shorter wavelength asperities. The surface modification was investigated experimentally by cold rolling of aluminium strips. The power spectral density of the roughness was used to extract appropriate amplitudes for the short and longwavelength components of roughness. The change in roughness amplitudes showed excellent agreement with theory.

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33

Chen, Ming y Hua Kun Yu. "Modeling Developable Mesh Surface by Lofting". Advanced Materials Research 591-593 (noviembre de 2012): 814–17. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.814.

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In the metal building and garment industries, product model is required to be or closed to be developable surface (can be flattened onto planar patterns without any distortion, tear or stretch).Current work mainly focuses on interpolating only two curves with a narrow developable strip, and lose the generality of applications in industries, which often require N (N>2) curves to determine the final shape feature, and seek one interpolated developable surface. In this paper, a new developability degree criterion is introduced first and a novel lofting algorithm is proposed to model a quasi-developable mesh surface for the given characteristic curves. The curves are first adaptively sampled and then planar triangles are tiled to interpolate all sampling points. The optimal triangulation in terms of given criterion is mapped as one shortest-path finding graph problem, which can be solved by using well-known Dijkstra’s algorithm.

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34

Kent Christensen, A. y Hayden G. Coon. "Organization of the thyroglobulin polysome, studied in Endoplasmic Reticulum surface views of rough endoplasmic reticulum in cultured rat thyroid cells". Proceedings, annual meeting, Electron Microscopy Society of America 48, n.º 3 (12 de agosto de 1990): 546–47. http://dx.doi.org/10.1017/s0424820100160285.

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Thyroglobulin is synthesized in the thyroid gland and is subsequently degraded to provide thyroid hormones. Rat thyroglobulin is made up of two identical 330 kD subunits, and the mRNA for each subunit contains about 8,500 nucleotides. Since polysomes have approximately one ribosome for each 90-100 nucleotides of mRNA, a polysome of about 85-95 ribosomes would be expected for thyroglobulin. We have been interested in how this very large polysomes is organized on the membranes of the rough endoplasmic reticulum (RER).It is well known that bound polysomes assume characteristic shapes on the surface of the RER, resembling beads on a string arranged in circles, spirals, loops, hairpins or other forms. These polysomal shapes can be observed in conventional electron micrographs when the membranes of the RER are seen in surface or en face view, rather than in the usual cross section. Clearcut surface views are infrequent, but the likelihood of seeing them is greatly improved when flattened cells in culture are sectioned in the plane of the cell, since the RER in a flattened cell tends to be oriented in that plane.

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35

Cárdenas, Miguel Meléndez, Claudio Gumane Francisco Juizo, Neptalí Bustamante Guillén, Hector Enrique Gonzáles Mora, Ricardo Jorge Klitzke y Márcio Pereira Da rocha. "SURFACE QUALITY OF PERUVIAN AMAZON WOODS SUBMITTED FOR PLANNING AND SANDING". FLORESTA 49, n.º 4 (19 de septiembre de 2019): 671. http://dx.doi.org/10.5380/rf.v49i4.57573.

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The present study aimed to evaluate the quality of the machined surface of wood of Peruvian Amazonian species under industrial processing conditions. For this, planks of capirona (Calycophyllum spruceanum), cachimbo (Cariniana domestica) and copaíba (Copaifera paupera) were obtained from which four specimens of each species were removed and selected. The specimens were previously conditioned and subsequently submitted to planing and sanding operations, considering three cutting orientations (tangential, radial and intermediate). Then, the quality of the flattened and sanded surfaces of the studied species was evaluated by measuring the surface roughness (Ra) by means of a digital needle detection roughness meter. The results indicated significant differences in wood surface quality among the species in the three evaluated cutting planes, and the capirona radial plane had better planing and sanding quality. Concomitantly, due to the operations performed, the capirona wood allowed a greater possibility for better finishing, followed by cachimbo and copaíba wood, thus being grouped in the 1st, 2nd, and 3rd surface quality classes, respectively.

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36

Shouqing, Xue y Liu Xiaohui. "Preparation and Anticorrosion of Octadecyl Trichlorosilane SAMs for Copper Surface". International Journal of Analytical Chemistry 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/4975714.

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The self-assembled monolayer (SAM) was prepared using octadecyl trichlorosilane (OTS) in distilled solution on the copper surface. The effect of inhibitor concentration on the rate of inhibition efficiency and corrosion rate in corrosion medium on copper by using polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM) was studied. The results showed that OTS SAMs exhibit the better corrosion resistance; the corrosion potential of copper OTS SAMs protection increased by about 1.02 V, while the corrosion current density decreased to 0.59 μA/cm2. The corrosion rate is minimized and flattened and can reach 9.2% while the inhibition efficiency reached 95.4%, when the corrosion inhibitor has concentration of 40 ppm.

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37

Zhuang, Mei Ling, Xiao Feng Zhang, Jian An Fang y Cheng Jian Zhao. "The Application and Design for the Algorithm to Search the Shortest Path in the Clothing Surface Flattening". Applied Mechanics and Materials 330 (junio de 2013): 565–68. http://dx.doi.org/10.4028/www.scientific.net/amm.330.565.

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The darts transfer principles of garment pattern design are used to design the split. For those splits belong to nonfunctional dividing the auxiliary line need to be designed and searched and they are realized by the shortest path searching algorithm. The undeveloped surface in the body is flattened effectively by the auxiliary path design. It not only makes the least distortion but also the most practicality.

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38

Brinksmeier, Ekkard, Yildirim Mutlugünes, Grigory Antsupov y Kai Rickens. "New Tool Concepts for Ultra-Precision Grinding". Key Engineering Materials 516 (junio de 2012): 287–92. http://dx.doi.org/10.4028/www.scientific.net/kem.516.287.

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This paper presents advanced tools for ultra precision grinding which offer a high wear resistance and can be used to generate high-quality parts with an ultraprecise surface finish. The first approach features defined dressed, coarse-grained, single layered, metal bonded diamond grinding wheels. These grinding wheels are called Engineered Grinding Wheels and have been dressed by an adapted conditioning process which leads to uniform abrasive grain protrusion heights and flattened grains. This paper shows the results from grinding optical glasses with such Engineered Grinding Wheels regarding the specific forces and the surface roughness. The results show that the cutting mechanism turns into ductile removal and optical surfaces are achievable. On the other hand, the specific normal force F´n increases due to increased contact area of the flattened diamond grains. It is shown that the topography of the Engineered Grinding Wheels has a strong beneficial influence on surface roughness. The second new tool for ultra precision grinding is made of a CVD (Chemical Vapour Deposition) poly-crystalline diamond layer with sharp edges of micrometre-sized diamond crystallites as a special type of abrasive. The sharp edges of the crystallites act as cutting edges which can be used for grinding. It is shown that by using CVD-diamond-coated grinding wheels a high material removal rate and a high surface finish with surface roughness in the nanometre range can be achieved. The CVD-diamond layers exhibit higher wear resistance compared to conventional metal and resin bonded diamond wheels. In conclusion, this paper shows that not only conventional fine grained, multi-layered resinoid diamond grinding wheels but also coarse-grained and binderless CVD-coated diamond grinding wheels can be applied to machine brittle and hard materials by ultra precision grinding.

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39

Ke, Xian-Sheng, Taeyeon Kim, Vincent M. Lynch, Dongho Kim y Jonathan L. Sessler. "Flattened Calixarene-like Cyclic BODIPY Array: A New Photosynthetic Antenna Model". Journal of the American Chemical Society 139, n.º 39 (21 de septiembre de 2017): 13950–56. http://dx.doi.org/10.1021/jacs.7b08611.

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40

Zhang, Yongde, Peter B. Ahn, Daniel C. Fitzpatrick, Anneliese D. Heiner, Robert A. Poggie y Thomas D. Brown. "INTERFACIAL FRICTIONAL BEHAVIOR: CANCELLOUS BONE, CORTICAL BONE, AND A NOVEL POROUS TANTALUM BIOMATERIAL". Journal of Musculoskeletal Research 03, n.º 04 (diciembre de 1999): 245–51. http://dx.doi.org/10.1142/s0218957799000269.

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A laboratory test was undertaken to evaluate the interfacial frictional characteristics of cortical and cancellous bone, as well as a novel porous tantalum biomaterial (Hedrocel®, Implex Corp.). Three sets of tests were conducted to measure the friction coefficients of (1) bovine cancellous bone against bovine cortical bone; (2) net-shape formed porous tantalum against bovine cortical and cancellous bone; and (3) electron-discharge-machine formed (EDM'd) porous tantalum against bovine cortical and cancellous bone. The bovine cortical bone was tested in three conditions: periosteum-intact, periosteum-denuded and surface-flattened. An inclined plane apparatus was used to determine the coefficients of friction. By gradually increasing the substrate tilt, the angle of slippage was determined, and the friction coefficient was calculated. The average friction coefficients of cancellous bone against periosteum-intact, periosteum-denuded and surface-flattened cortical bone were 0.91±0.14, 0.61± 0.07 and 0.58±0.06, respectively. Porous tantalum specimens prepared from a preshaped vitreous carbon skeleton, when tested against periosteum-intact, periosteum-denuded and surface-flattened cortical bone, and against cancellous bone, had average friction coefficients of 1.10±0.18, 0.82±0.15, 0.86±0.11, and 0.98±0.17, respectively. Porous tantalum specimens prepared by electron-discharge machining, when tested against periosteum-intact cortical bone, periosteum-denuded cortical bone and cancellous bone, had average friction coefficients of 1.75±0.33, 0.74±0.07, and 0.88±0.09, respectively. The friction coefficient of the porous tantalum material was very high in comparison to natural bone autografts or allografts, and to conventional orthopedic implant coating materials (sintered beads and wire mesh). Other factors being equal, this high-friction characteristic would be expected to translate into higher initial stability of a porous tantalum implant, as compared to natural bone grafts.

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41

Sigamani, Ashokkumar y Arunai Nambiraj. "Comparison of surface dose delivered by 7 MV-unflattened and 6 MV-flattened photon beams". Reports of Practical Oncology & Radiotherapy 22, n.º 3 (mayo de 2017): 243–50. http://dx.doi.org/10.1016/j.rpor.2016.12.003.

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42

Ohtomo, Yudai, Shuichi Ogawa y Yuji Takakuwa. "Surface morphology of a Cu substrate flattened by a 2″ photoemission-assisted ion beam source". Surface and Interface Analysis 44, n.º 6 (2 de diciembre de 2011): 670–73. http://dx.doi.org/10.1002/sia.3863.

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43

Bensliman, F., A. Fukuda, N. Mizuta y M. Matsumura. "Analysis of Anodic Oxidation Current of Flattened p-Type Si(111) Surface in Aqueous Solution". Journal of The Electrochemical Society 150, n.º 9 (2003): G527. http://dx.doi.org/10.1149/1.1593047.

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44

Qi, Liang y Ju Li. "Adsorbate interactions on surface lead to a flattened Sabatier volcano plot in reduction of oxygen". Journal of Catalysis 295 (noviembre de 2012): 59–69. http://dx.doi.org/10.1016/j.jcat.2012.07.019.

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45

Alonso, Marcos, Alberto Izaguirre, Imanol Andonegui y Manuel Graña. "Optical Dual Laser Based Sensor Denoising for OnlineMetal Sheet Flatness Measurement Using Hermite Interpolation". Sensors 20, n.º 18 (22 de septiembre de 2020): 5441. http://dx.doi.org/10.3390/s20185441.

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Flatness sensors are required for quality control of metal sheets obtained from steel coils by roller leveling and cutting systems. This article presents an innovative system for real-time robust surface estimation of flattened metal sheets composed of two line lasers and a conventional 2D camera. Laser plane triangulation is used for surface height retrieval along virtual surface fibers. The dual laser allows instantaneous robust and quick estimation of the fiber height derivatives. Hermite cubic interpolation along the fibers allows real-time surface estimation and high frequency noise removal. Noise sources are the vibrations induced in the sheet by its movements during the process and some mechanical events, such as cutting into separate pieces. The system is validated on synthetic surfaces that simulate the most critical noise sources and on real data obtained from the installation of the sensor in an actual steel mill. In the comparison with conventional filtering methods, we achieve at least a 41% of improvement in the accuracy of the surface reconstruction.

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46

Kawai, N., K. Dohda, M. Saito, N. Hayashi y Z. Wang. "Friction Behavior in the Cup Ironing Process of Aluminum Sheets". Journal of Engineering for Industry 114, n.º 2 (1 de mayo de 1992): 175–80. http://dx.doi.org/10.1115/1.2899769.

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The object of this paper is to clarity the surface flattening mechanism in the cup ironing process based on the lubricating mechanism. A new experimental apparatus for the ironing process was made and experiments on ironing were carried out with aluminum cups using various lubricants and reductions in thickness. The experiments revealed that on the die surface the friction coefficient becomes minimum under the appropriate conditions of viscosity of lubricant and reduction in thickness. It was also confirmed that the cup surface is best flattened under conditions where the minimum friction coefficient appears.

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47

Zhao, Xiao-Shun, Li Yu, Xue Yang y Si-Yu Zhang. "Segmentation mapping and folding method of surfaces of revolution and its applications". Engineering Computations 36, n.º 4 (13 de mayo de 2019): 1305–22. http://dx.doi.org/10.1108/ec-06-2018-0271.

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Purpose The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution. Design/methodology/approach Irregular wrinkles and mesh distortions easily appear in the fold modeling of a complex curved surface. Aimed at this key technical problem, the segmentation mapping folding method (SMFM) is proposed in this paper. First, high-precision flattened planes were obtained by using segmentation mapping techniques. Second, the segmented planes were transformed into a folded and continuous geometric model by using matrix transformations. Finally, initial stress was used to modify the geometric folding errors, which ensured agreement with the inflated flexible fabric’s geometry and the original design. Findings Compared with the traditional folding method, SMFM has the advantages of good finite-element mesh quality, large radial compression rate, regular folds, etc. The surface area error and the volume error of the inflated single torus established by SMFM were only 1.2 per cent, showing that SMFM has high modeling accuracy. The numerical results of an inflatable re-entry vehicle are presented to demonstrate the reliability, feasibility and applicability of SMFM. Moreover, the stress modification reduced the problems of stress concentration and mesh distortions, improving the accuracy and stability of the numerical calculations. Originality/value In this paper, for the first time, a folding method for modeling complicated folded fabric is proposed. This methodology can be used to model the multidimensional compression and regular folds of complex surfaces of revolution that cannot be flattened and to improve the accuracy and stability of the numerical calculations.

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48

Okada, Masato, Yuki Miyagoshi y Masaaki Otsu. "Roller Burnishing Method with Active Rotation Tool - Better Surface Finish than Conventional Roller Burnishing". Key Engineering Materials 749 (agosto de 2017): 9–14. http://dx.doi.org/10.4028/www.scientific.net/kem.749.9.

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This paper proposes a roller burnishing method that controls the sliding direction of the burnishing tool on the surface of cylindrical workpiece. In this study, the sliding direction was set by inclining the axis of the burnishing tool with respect to the axis of the workpiece and by actively rotating the roller of the burnishing tool. The workpiece was a cylindrical aluminum alloy bar, which was rotated in a bench lathe. The burnished surfaces at several sliding angles between 15º and 90º were evaluated. The sliding direction, which is set according to a theoretical equation, was experimentally obtained for every sliding angle in the range of 15-90º with respect to the circumferential direction of the workpiece. The sectional profile was flattened and surface roughness was decreased with increasing sliding angle. As a result, the burnished surfaces obtained in this work were superior to those obtained in an earlier study by the authors, in which the burnishing tool was not actively rotated.

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49

Chrisman, Donald. "Reply to Shaffer and Baker". American Antiquity 62, n.º 3 (julio de 1997): 561. http://dx.doi.org/10.2307/282174.

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Accurate measurement of the number of epidermal ridges must be done directly from the artifacts, using a nearly flat surface or a very thin dental silicone mold pulled off and flattened. Measurements from enlarged pictures of 3-D rounded objects converted to 2-D are highly inaccurate and do not correct for the nearly 20 percent shrinkage factor.

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50

Li, Qunyang y Kyung-Suk Kim. "Micromechanics of friction: effects of nanometre-scale roughness". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 464, n.º 2093 (19 de febrero de 2008): 1319–43. http://dx.doi.org/10.1098/rspa.2007.0364.

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Nanometre-scale roughness on a solid surface has significant effects on friction, since intersurface forces operate predominantly within a nanometre-scale gap distance in frictional contact. To study the effects of nanometre-scale roughness, two novel atomic force microscope friction experiments were conducted, each using a gold surface sliding against a flat mica surface as the representative friction system. In one of the experiments, a pillar-shaped single nano-asperity of gold was used to measure the molecular-level frictional behaviour. The adhesive friction stress was measured to be 264 MPa and the molecular friction factor 0.0108 for a direct gold–mica contact. The nano-asperity was flattened in contact, although its hardness at this length scale is estimated to be 3.68 GPa. It was found that such a high pressure could be reached with the help of condensed water capillary forces. In the second experiment, a micrometre-scale asperity with nanometre-scale roughness exhibited a single-asperity-like response of friction. However, the apparent frictional stress, 40.5 MPa, fell well below the Hurtado–Kim model prediction of 208–245 MPa. In addition, the multiple nano-asperities were flattened during the frictional process, exhibiting load- and slip-history-dependent frictional behaviour.

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