Reflectivity images of the lower crust and uppermost mantle beneath the Illinois basin have been derived from reprocessing of several hundred kilometers of industry seismic reflection data using extended vibroseis recorrelation. The recorrelation was based on extending an originally 4-s correlated record, acquired with a 16-s sweep from 14 to 126 Hz, to the absolute limit of the full 20 s (~70 km) listening travel time. The reconstructed bandwidth includes frequency components suitable for imaging structures from signals received from both sedimentary basin reflectors and those received from reflectors in the deep crust and upper mantle. Mantle and sub-Moho reflectors are imaged down to 18 s two-way travel time (~62 km) and are observed on intersecting profiles generally dipping to the southwest and striking northwest-southeast. Occasional Moho reflections are also observed across the profiles (~12 s or ~38 km) while reflectivity in the lower crust is generally marked by intermittent horizontal packages and short, gently dipping reflections and diffraction segments. The presence of newly observed mantle reflectivity beneath the Illinois basin indicates significant upper mantle heterogeneity, relative to other parts of the USA studied using reflection methods. The relatively isolated occurrence of mantle reflections beneath the basin makes it difficult to uniquely infer their origin. However, available geologic and geophysical constraints, especially from geochemical and geochronological studies of drilled basement rocks, effectively limit the possibilities to: (1) remnants or "scars" of sub-crustal processes associated with lithospheric extension or delamination related to the melting of the Proterozoic crust that led to the emplacement of the granite--rhyolite province that underlies much of USA Midcontinent; or (2) deformation caused by plate subduction associated with the hypothetical accretion of a juvenile arc to the pre-1.6 Ga southern margin of the Laurentian continent.

Quantifying the appearance of a surface is an important aspect in quality control. Becauseobjects at room temperature emit negligible amounts of radiation into the visible spectrum, aspectsof their appearance may be quantified using reflected light. Therefore, the appearance of opaquesurfaces may be quantified using measurements of the spectral, bidirectional reflectivity. However,measuring the spectral, bidirectional reflectivity of even one point at every set of incident andreflected directions is a time intensive process that is infeasible for quality control.The objective of this work was to determine whether a limited number of spectral, bidirectionalreflectance measurements may be used to characterize the appearance of an opaque surfaceat room temperatures. The results presented in this thesis demonstrate that measurements of thespectral bidirectional reflectivity in the visible spectrum at four sets of specular reflections - 20°,45°, 60°, and 85° - with a resolution of 5 nm may be used to quantify the appearance of an opaquesurface at room temperature. These measurements are converted into parameters called the bidirectionalreflectance appearance parameters (BRAPs). These BRAPs include L*, a*, b* (whichdefine the color of the surface), G20, G60, G85 (which define the gloss of the surface), and H(which describes the haze of the surface). It is shown that surfaces which appear similar havesimilar BRAPs and surfaces which appear different have different BRAPs.

This research provides the evaluation of the technical measurements of pavement marking materials from a two-year data collection on 2002 National Transportation Product Evaluation Program (NTPEP)?s Mississippi Test Deck from June, 2002 to June 2004. The materials studied in this research were divided into permanent and temporary material groups on two different pavement surfaces ---- asphalt and concrete. The retro reflectivity and durability of permanent marking materials among different surfaces, colors and groups were studied. Also the characteristics for temporary tapes, which include internal tape strength, adhesion, tackiness and dicernablity were compared and regressed. This correlation analysis is to see whether these ratings are correlated to each other. The results of this study can be used for estimating service lives of pavement marking materials. They also can be used by states to select appropriate pavement marking materials for different needs.

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Yes / A new approach is described herein, where neutron reflectivity measurements that probe changes in the density profile of thin films as they absorb material from the gas phase have been combined with a Love wave based gravimetric assay that measures the mass of absorbed material. This combination of techniques not only determines the spatial distribution of absorbed molecules, but also reveals the amount of void space within the thin film (a quantity that can be difficult to assess using neutron reflectivity measurements alone). The uptake of organic solvent vapours into spun cast films of polystyrene has been used as a model system with a view to this method having the potential for extension to the study of other systems. These could include, for example, humidity sensors, hydrogel swelling, biomolecule adsorption or transformations of electroactive and chemically reactive thin films. This is the first ever demonstration of combined neutron reflectivity and Love wave-based gravimetry and the experimental caveats, limitations and scope of the method are explored and discussed in detail.

Interfacial features of polymers are a complex, fascinating topic, and industrially very important. There is clearly a need to understand interactions between polymer layers as they can be used for controlling surface properties, colloidal stability and lubrication. The aim of my Ph.D study was to investigate fundamental phenomena of polymers at interfaces, covering adsorption, interactions between polymer layers and surfactants, surface forces and friction between adsorbed layers. A branched brush layer with high water content was formed on silica surfaces by a diblock copolymer, (METAC)m-b-(PEO45MEMA)n, via physisorption. The adsorption properties were determined using several complementary methods. Interactions between pre-adsorbed branched brush layers and the anionic surfactant SDS were investigated as well. Surface forces and friction between polymer layers in aqueous media were investigated by employing the Atomic Force Microscopy (AFM) colloidal probe technique. Friction forces between the surfaces coated by (METAC)m-b-(PEO45MEMA)n in water are characterized by a low friction coefficient. Further, the layers remain intact under high load and shear, and no destruction of the layer was noted even under the highest pressure employed, about 50 MPa. Interactions between polymer layers formed by a temperature responsive diblock copolymer, PIPOZ60-b-PAMPTMA17 (phase transition temperature of 46.1 °C), was investigated in the temperature interval 25-50 °C by using the AFM colloidal probe technique. Friction between the layers increases with increasing temperature (25-45 °C), while at 50 °C friction was found to be slightly lower than that at 45 °C. We suggest that this is due to decreased energy dissipation caused by PIPOZ chains crystallizing in water above the phase transition temperature. The structure of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers was determined by X-ray reflectometry. Surface forces and friction between DPPC bilayer-coated silica surfaces were measured utilizing the AFM colloidal probe technique. Our study showed that DPPC bilayers are able to provide low friction forces both in the gel (below ≈ 41°C) and in the liquid crystalline state (above ≈ 41°C). However, the load bearing capacity is lower in the gel state. This is attributed to a higher rigidity and lower self-healing capacity of the DPPC bilayer in the gel state. Friction forces in single asperity contact acting between a micro-patterned silicon surface and an AFM tip was measured in air. We found that both nanoscale surface heterogeneities and the µm-sized depressions affect friction forces, and considerable reproducible variations were found along a particular scan line. Nevertheless, Amontons’ first rule described average friction forces reasonably well. Amontons’ third rule and Euler’s rule were found to be less applicable to our system. / <p>QC 20141209</p>

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