46,249 research outputs found
Quantitative Nanofriction Characterization of Corrugated Surfaces by Atomic Force Microscopy
Atomic Force Microscopy (AFM) is a suitable tool to perform tribological
characterization of materials down to the nanometer scale. An important aspect
in nanofriction measurements of corrugated samples is the local tilt of the
surface, which affects the lateral force maps acquired with the AFM. This is
one of the most important problems of state-of-the-art nanotribology, making
difficult a reliable and quantitative characterization of real corrugated
surfaces. A correction of topographic spurious contributions to lateral force
maps is thus needed for corrugated samples. In this paper we present a general
approach to the topographic correction of AFM lateral force maps and we apply
it in the case of multi-asperity adhesive contact. We describe a complete
protocol for the quantitative characterization of the frictional properties of
corrugated systems in the presence of surface adhesion using the AFM.Comment: 33 pages, 9 figures, RevTex 4, submitted to Journal of Applied
Physic
Surface characterization data for tethered polyacrylic acid layers synthesized on polysulfone surfaces.
The data presented are supplementary to an article [Kim et al., 2019] on synthesis and surface characterization of tethered polyacrylic acid (PAA) layers on polysulfone (PSf) film/membrane surfaces via atmospheric pressure plasma-induced graft polymerization (APPIGP). Data on surface characterization of the synthesized tethered PAA layers includes: AFM topographic surface images and height distributions of surface features, dry layer thickness, chain rupture length distributions determined via AFM based force spectroscopy (AFM-FS), in addition to measurements of water contact angles. Fouling propensity data for ultrafiltration of alginic acid as a model foulant are also provided for native and PAA grafted PSf ultrafiltration (UF) membranes
Scanning Probe Microscopy for polymer film characterization in food packaging
Scanning probe microscopy (SPM) is a branch of microscopy allowing
characterization of surfaces at the micro-scale by means of a physical probe (with a size of a few
microns) raster scanning the sample. SPMs monitor the interaction between such probe and the
surface and, depending on the specific physical principles causing the interaction, they allow
generation of a quantitative map of topographic properties: geometrical, optical, electrical,
magnetic, etc. This is of the greatest interest, in particular whenever functional surfaces have to
be characterized in a quantitative manner. The present paper discusses the different applications
of Scanning Probe Microscopy techniques for a thorough characterization of polymer surfaces,
of specific interest in particular for the case of food packaging applications
Characterization of nanometer-sized, mechanically exfoliated graphene on the H-passivated Si(100) surface using scanning tunnelling microscopy
We have developed a method for depositing graphene monolayers and bilayers
with minimum lateral dimensions of 2-10 nm by the mechanical exfoliation of
graphite onto the Si(100)-2x1:H surface. Room temperature, ultra-high vacuum
(UHV) tunnelling spectroscopy measurements of nanometer-sized single-layer
graphene reveal a size dependent energy gap ranging from 0.1-1 eV. Furthermore,
the number of graphene layers can be directly determined from scanning
tunnelling microscopy (STM) topographic contours. This atomistic study provides
an experimental basis for probing the electronic structure of nanometer-sized
graphene which can assist the development of graphene-based nanoelectronics.Comment: Accepted for publication in Nanotechnolog
Nanomanufacturing of titania interfaces with controlled structural and functional properties by supersonic cluster beam deposition
Great emphasis is placed on the development of integrated approaches for the
synthesis and the characterization of ad hoc nanostructured platforms, to be
used as templates with controlled morphology and chemical properties for the
investigation of specific phenomena of great relevance for technological
applications in interdisciplinary fields such as biotechnology, medicine and
advanced materials. Here we discuss the crucial role and the advantages of thin
film deposition strategies based on cluster-assembling from supersonic cluster
beams. We select cluster-assembled nanostructured titania (ns-TiO2) as a case
study to demonstrate that accurate control over morphological parameters can be
routinely achieved, and consequently over several relevant interfacial
properties and phenomena, like surface charging in a liquid electrolyte, and
proteins and nanoparticles adsorption
Characterization of subglacial landscapes by a two-parameter roughness index
Peer reviewedPublisher PD
The topographic development and areal parametric characterization of a stratified surface polished by mass finishing
Mass finishing is amongst the most widely used finishing processes in modern manufacturing, in applications from deburring to edge radiusing and polishing. Processing objectives are varied, ranging from the cosmetic to the functionally critical. One such critical application is the hydraulically smooth polishing of aero engine component gas-washed surfaces. In this, and many other applications the drive to improve process control and finish tolerance is ever present. Considering its widespread use mass finishing has seen limited research activity, particularly with respect to surface characterization. The objectives of the current paper are to; characterise the mass finished stratified surface and its development process using areal surface parameters, provide guidance on the optimal parameters and sampling method to characterise this surface type for a given application, and detail the spatial variation in surface topography due to coupon edge shadowing. Blasted and peened square plate coupons in titanium alloy are wet (vibro) mass finished iteratively with increasing duration. Measurement fields are precisely relocated between iterations by fixturing and an image superimposition alignment technique. Surface topography development is detailed with âlog of process durationâ plots of the âareal parameters for scale-limited stratified functional surfacesâ, (the Sk family). Characteristic features of the Smr2 plot are seen to map out the processing of peak, core and dale regions in turn. These surface process regions also become apparent in the âlog of process durationâ plot for Sq, where lower core and dale regions are well modelled by logarithmic functions. Surface finish (Ra or Sa) with mass finishing duration is currently predicted with an exponential model. This model is shown to be limited for the current surface type at a critical range of surface finishes.
Statistical analysis provides a group of areal parameters including; Vvc, Sq, and Sdq, showing optimal discrimination for a specific range of surface finish outcomes. As a consequence of edge shadowing surface segregation is suggested for characterization purposes
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