Search results for "ROUGHNESS"

Surface roughness, porosity, and texture as modifiers of cellular adhesion.

2009

Substrate topography in the micrometer range is reviewed as a modifier of the response of cultured cells and of biocompatibility when implanted into tissues. Characterization methods for substrate topography are discussed, including scanning electron microscopy, profilometry, laser scanning, and confocal microscopy. Because of the current technical limitations in reproducing micron-level topographic details, only one method, ion-beam etching, has been found suitable for texturing substrates on nonplanar surfaces.

Wetting ability of an acetone/based etch rinse adhesive after NaOCl-treatment

2011

Objectives: to evaluate the effect of sodium hypochlorite (NaOCl) treatment on surface dentin roughness (Ra) and contact angle (CA) when using Prime&Bond NT adhesive (PB NT). Study Design: Extracted human third molars were sectioned to expose flat, superficial and deep dentin surfaces. CA and Ra were measured (1) before and (2) after 35% H3PO4 etching, and (3) H3PO4 etching + 5% NaOCl treated for 2 minutes before the application of PB NT. CA was measured by the Axisymmetric Drop Shape Analysis Technique using distilled and deionized water and PB NT. Roughness was evaluated with a profilometer, twelve radial measurements were performed in each treatment surface. Data were analyzed with two-w…

An advance Towards the Synthesis of Ag Nanorod Arrays with Controlled Surface Roughness for SERS Substrates

2016

An innovative approach to produce silver nanorod (NRs) arrays with controlled morphological parameters and surface roughness is presented. The Ag NRs were obtained using a three-stage fabrication process based on the electron beam exposure of a metal-polymer nanocomposite resist on a transparent substrate and development, a post bake and then a series of non-electrochemical metallization steps. After each step the evolution of the Ag NRs was characterized by scanning electron microscopy (SEM) for morphology and optical transmittance (T) measurements for Localized Surface Plasmon Resonance (LSPR). The transmittance measurements were interpreted using models based on the Finite Element Method…

Germanium Doped CHxMicroshells for LMJ Targets

2011

AbstractAt the CEA Laser “Megajoule” facility, amorphous hydrogenated carbon (a-C:H or CHx) is the nominal ablator used to achieve inertial confinement fusion experiments. These targets are filled with a fusible mixture of deuterium-tritium in order to perform ignition.Since the achievement of ignition greatly depends on the physical properties of the shell, there must be precise control of thicknesses, doping concentration, and roughness. Experimental devices associated with suitable characterizations are described in this paper. The tolerances and yields for each specification are also presented. Some specifications are largely reached; high-frequency surface roughness due to isolated sur…

Smooth crack-free targets for nuclear applications produced by molecular plating

2013

The production process of smooth and crack-free targets by means of constant current electrolysis in organic media, commonly known as molecular plating, was optimized. Using a Nd salt, i.e., [Nd(NO3)(3)center dot 6H(2)O], as model electrolyte several constant current density electrolysis experiments were carried out to investigate the effects of different parameters, namely the plating solvent (isopropanol and isobutanol mixed together, pyridine, and N,N-dimethylformamide), the electrolyte concentration (0.11, 0.22, 0.44 mM), the applied current density (0.17, 0.3, 0.7, and 1.3 mA/cm(2)), and the surface roughness of the deposition substrates (12 and 24 nm). Different environments (air and …

Three-Dimensional Microstructural Properties of Nanofibrillated Cellulose Films

2014

Abstract: Nanofibrillated cellulose (NFC) films have potential as oxygen barriers for, e.g., food packaging applications, but their use is limited by their hygroscopic characteristics. The three-dimensional microstructure of NFC films made of Pinus radiata (Radiata Pine) kraft pulp fibres has been assessed in this study, considering the structural development as a function of relative humidity (RH). The surface roughness, micro-porosity, thickness and their correlations were analyzed using X-ray microtomography (X–μCT) and computerized image analysis. The results are compared to those from scanning electron microscopy and laser profilometry. Based on a series of films having varying amounts…

Spreading dynamics of three-dimensional droplets by the lattice-Boltzmann method

2000

Abstract We have simulated spreading of small droplets on smooth and rough solid surfaces using the three-dimensional lattice-Boltzmann method. We present results for the influence of the initial distance and shape of the drop from the surface on scaling of droplet radius R as a function of time. For relatively flat initial drop shapes our observations are consistent with Tanner's law R ∼ t q , where q =1/10. For increasingly spherical initial shapes, the exponent q increases rapidly being above one half for spherical droplets initially just above the surface. As expected, surface roughness slows down spreading, decreases the final drop radius, and results in irregular droplet shape due to …

Turbulence structure and coherent motion in a straight laboratory flume

2012

Turbulent Flow Structures For Different Roughness Conditions of Channel Walls: Results of experimental

2012

A methodology for the semi-automatic generation of analytical models in manufacturing

2018

International audience; Advanced analytics can enable manufacturing engineers to improve product quality and achieve equipment and resource efficiency gains using large amounts of data collected during manufacturing. Manufacturing engineers, however, often lack the expertise to apply advanced analytics, relying instead on frequent consultations with data scientists. Furthermore, collaborations between manufacturing engineers and data scientists have resulted in highly specialized applications that are not relevant to broader use cases. The manufacturing industry can benefit from the techniques applied in these collaborations if they can be generalized for a wide range of manufacturing probl…