50,499 research outputs found
On the interpretation of lateral manganin gauge stress measurements in polymers
Encapsulated wire-element stress gauges enable changes in lateral stress during
shock loading to be directly monitored. However, there is substantial debate
with regards to interpretation of observed changes in stress behind the shock
front; a phenomenon attributed both to changes in material strength and shock-
dispersion within the gauge-encapsulation. Here, a pair of novel techniques
which both modify or remove the embedding medium where such stress gauges are
placed within target materials have been used to try and inform this debate. The
behavior of three polymeric materials of differing complexity was considered,
namely polystyrene, the commercially important resin transfer moulding RTM 6
resin and a commercially available fat lard. Comparison to the response of
embedded gauges has suggested a possible slight decrease in the absolute
magnitude of stress. However, changing the encapsulation has no detectable
effect on the gradient behind the shock in such polymeric systems
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Visual analysis of sensitivity in CAT models: interactive visualisation for CAT model sensitivity analysis
Short-Chained Oligo(Ethylene Oxide)-Functionalized Gold Nanoparticles: Realization Of Significant Protein Resistance
Protein corona formed on nanomaterial surfaces play an important role in the bioavailability and cellular uptake of nanomaterials. Modification of surfaces with oligoethylene glycols (OEG) are a common way to improve the resistivity of nanomaterials to protein adsorption. Short-chain ethylene oxide (EO) oligomers have been shown to improve the protein resistance of planar Au surfaces. We describe the application of these EO oligomers for improved protein resistance of 30 nm spherical gold nanoparticles (AuNPs). Functionalized AuNPs were characterized using UV-Vis spectroscopy, dynamic light scattering (DLS), and zeta potential measurements. Capillary electrophoresis (CE) was used for separation and quantitation of AuNPs and AuNP-protein mixtures. Specifically, nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM) was employed for the determination of equilibrium and rate constants for binding between citrate-stabilized AuNPs and two model proteins, lysozyme and fibrinogen. Semi-quantitative CE analysis was carried out for mixtures of EO-functionalized AuNPs and proteins, and results demonstrated a 2.5-fold to 10-fold increase in protein binding resistance to lysozyme depending on the AuNP surface functionalization and a 15-fold increase in protein binding resistance to fibrinogen for both EO oligomers examined in this study
Instrumentation design study for testing a hypersonic ramjet engine on the x-15 a-2. volume 2- preliminary design of in-flight thrust/drag measuring device
Inflight thrust and drag measuring device for hypersonic ramjet engine on X-15A-2 aircraf
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