Search results for "Roughne"
showing 10 items of 222 documents
Improved Cu2O/AZO Heterojunction by Inserting a Thin ZnO Interlayer Grown by Pulsed Laser Deposition
2019
Cu2O/ZnO:Al (AZO) and Cu2O/ZnO/AZO heterojunctions have been deposited on glass substrates by a unique three-step pulsed laser deposition process. The structural, optical, and electrical properties of the oxide films were investigated before their implementation in the final device. X-ray diffraction analysis indicated that the materials were highly crystallized along the c-axis. All films were highly transparent in the visible region with enhanced electrical properties. Atomic force and scanning electron microscopies showed that the insertion of a ZnO layer between the Cu2O and AZO films in the heterojunction enhanced the average grain size and surface roughness. The heterojunctions exhibi…
In vitro preliminary study of osteoblast response to surface roughness of titanium discs and topical application of melatonin
2014
Objectives: To observe human osteoblast behavior cultured in vitro on titanium discs (Ti) in relation to surface roughness and melatonin application. Study Design: Human osteoblasts (MG-63) were cultured on 60 Ti6Al4V discs divided into three groups: Group I: discs treated with dual acid etching; Group II dual acid etching and blasting with calcium phosphate particles; Group III (control) machined discs. Surface roughness and topography of the discs were examined with scanning electron microscope (SEM) and confocal laser scanning electron microscope( CLSM). Osteoblast adhesion, proliferation and cell morphology were determined by means of fluorescence microscopy with Image-Pro Plus software…
Potential of amorphous Mo–Si–N films for nanoelectronic applications
2003
The properties of amorphous metallic molybdenum–silicon–nitrogen (Mo–Si–N) films were characterised for use in nanoelectronic applications. The films were deposited by co-sputtering of molybdenum and silicon targets in a gas mixture of argon and nitrogen. The atomic composition, microstructure and surface roughness were studied by RBS, TEM and AFM analyses, respectively. The electrical properties were investigated in the temperature range 80 mK to 300 K. No transition into a superconductive state was observed. Nanoscale wires were fabricated using electron beam lithography with their properties measured as a function of temperature.
Microscopic observation of unworn siloxane-hydrogel soft contact lenses by atomic force microscopy
2006
In the present study, samples of lotrafilcon A, balafilcon A, and galyfilcon A contact lenses were observed by atomic force microscopy (AFM) in tapping mode at areas ranging from 0.25 to 400 m2. Mean roughness (Ra), root-mean-square roughness (Rms) and maximum roughness (Rmax) in nanometers were obtained for the three lens materials at different magnifications. The three contact lenses showed significantly different surface topography. However, roughness values were dependent of the surface area to be analyzed. For a 1 m2 area, statistics revealed a significantly more irregular surface of balafilcon A (Ra = 6.44 nm; Rms = 8.30 nm; Rmax = 96.82 nm) compared with lotrafilcon A (Ra = 2.40 nm; …
Ultra-structure characterization of self-etching treated cementum surfaces
2010
Objectives: to evaluate the effect of different conditioning treatments on surface roughness and topography of dental cementum. Study Design: Extracted human canines were used for the present study. The mesial surface from the cervical third of the roots were ground flat with wet 600-grit silicon carbide paper. They were polished (up to 1/4 µm diamond paste) and treated as follows: 1) No treatment, 2) 35% H3PO4 during 15 s, 3) Clearfil SE Bond primer (SEB), 4) One-Up Bond F (OUB). The adhesive systems were applied following manufacturer?s instructions. SEB primer and OUB were removed from surfaces by washing and ultrasonic agitation with ascending ethanol solutions. Digital images of treate…
Durability of biodegradable polymers for the conservation of cultural heritage
2019
The use of polymers for conservation of cultural heritage is related to the possibility to slow down or stop natural deterioration which, in many cases, corresponds to stopping the entrance of liquid water and to favour spontaneous water vapour removal. Unfortunately, hydrophobicity is generally favoured by surface roughness and thus competitive with transparency. It is therefore important to find an optimal balance hydrophobicity, transparency and durability (especially to photooxidation). However, polymers typically used for applications in this field come from non-renewable resources and are not biodegradable. In this work, the mechanical, structural and optical properties of PLA, PBAT a…
Electropolishing of CuZn brasses and 316L stainless steels: Influence of alloy composition or preparation process (ALM vs. standard method)
2016
International audience; In the present paper, electropolishing behavior of different brass alloys (CuZn39Pb2, CuZn42) in phosphoric acid is studied to observe the impact of alloying elements on polishing quality. In the same way, the influence of the manufacturing process is also evaluated through the comparison of a “standard” stainless steel and a stainless steel prepared by Additive Laser Manufacturing (ALM). An electrochemical study was first performed to determine the best treatment conditions for each material/electrolyte pair and to study the electropolishing mechanism and its kinetic dependence on diffusion. Metallic samples are fully characterized before and after electropolishing …
Deposition and characterization of ZnO thin films on GaAs and Pt/GaAs substrates
2020
Abstract This work reports the deposition and characterization of piezoelectric ZnO thin films on semi-insulating GaAs substrates for the fabrication of bulk acoustic waves sensors. ZnO films are deposited at 350 °C and low deposition rate using reactive radio frequency magnetron sputtering. The use of a Pt bottom electrode, between ZnO and GaAs, with and without Ti buffer layer, as well as the effect of the substrate crystallographic orientation are investigated. The characterization of the deposited films is performed to determine the optimal parameters for obtaining high-quality films and ZnO residual conductivity. ZnO films are textured along the c-axis for all GaAs cuts. The highest st…
Whispering gallery mode resonators covered by a ZnO nanolayer
2020
Abstract The exceptional ability of whispering gallery mode resonators (WGMRs) to confine light within makes them interesting for sensing applications. The small size and high values of quality (Q) factors of the WGMR can be combined with a broad range of supporting optical elements. The surface of the resonator can be coated to enhance the desired attributes. In this paper, the impact of the ZnO layer thickness on the Q-factor of the WGMR has been studied. WGMRs were fabricated on a tip of a standard telecom fiber melted with an oxyhydrogen flame. The surface of the WGMR was coated with ZnO nanolayers of different thickness (5–100 nm) by atomic layer deposition (ALD). The Q-factor of as-pr…
Experimental investigation of effect of printing direction and surface roughness on the mechanical properties of AlSi10Mg-alloy produced by selective…
2021
The additive manufacturing has initially gained popularity for production of non-loadbearing parts and components or in the fields where the material strength and ductility are less important such as modelling and rapid prototyping. But as the technology develops, availability of metal additive manufacturing naturally dictates the desire to use the produced components in load-bearing parts. This requires not-only a thorough documentation on the mechanical properties but also additional and independent research to learn the expected level of variation of the mechanical properties and what factors affect them. The presented paper investigates strength, ductility, hardness, and microstructure …