This thesis presents a limited investigation of the effects
of various etches on the surface properties of silicon. Surface
recombination velocities of silicon under different etching treatments
are compared by using the photoelectromagnetic effect. A
measure of the minority carriers lifetime by the photoconductive
decay method provides another means of...
The surface areas and pore size distributions of a
series of terrigenous marine sediments were measured by gas
adsorption. The sediment samples were taken from the continental
terrace off the coast of Oregon near Newport.
Sampling stations ranged up to 35 miles off shore between
44°20' and 45° north latitude....
Measurable surface parameters which may be related to the response evoked upon contact with biofluids have been suggested to provide direction for characterization, prediction, and ultimate control of biofluid behavior at interfaces. With respect to fouling of heat exchange equipment by biofluids, such properties may be useful for the development...
Ellipsometry was used to study the effects of surface energetics
and temperature on the equilibrium adsorptive behavior exhibited by
β-lactoglobulin. β-Lactoglobulin isotherms at 25, 37, and 55°C were
constructed for this purpose. The surfaces of acrylic, polycarbonate,
polyester, glass, and #304 stainless steel were contacted with protein
solutions of varying...
An important aspect in device technology is the
processing of GaAs to produce highly-resolved etch
patterns on the substrate. This is done typically on the
GaAs(100) surface. Recently, a number of methods, all
using chlorinated vapor reactants, have been applied to
fabrication of GaAs devices. In spite of these
technological...
There have been many attempts to characterize and mimic natural fluid-based adhesive systems. However, very few of these studies have examined surface or interfacial interactions between adhesive and substrate. Furthermore, until now no study has used a combination of surface analytical and kinematic techniques to determine the precise chemical mechanisms...
The interactions of chemical species with a solid surface play a role in many everyday applications such as heterogeneous catalysis, corrosion, and degradation reactions. Understanding the reaction kinetics and thermodynamics via rate constants and equilibrium constants, which require knowledge of the adsorbed species’ entropy, is essential for tuning these surface...
In this thesis, we investigated the surface composition and orientation of both pure room-temperature ionic liquids (Ils) and binary mixtures of the ILs of the type consisting of the 1-alkyl-3-methylimidazolium ([C[subscropt n]mim]⁺, n=4, 8, and 12) cation coupled with either [PF₆]⁻, [BF₄]⁻, [Cl]⁻, or [Br]⁻. The surfaces of the ILs...
Boiling heat transfer is studied for its ability to dissipate high fluxes and achieve heat transfer coefficients two orders of magnitude greater than single-phase heat transfer systems. Heater surface enhancement with increased surface area, varied geometry, wettability contrast and micro/nano-structures can further enhance boiling heat transfer performance through bubble nucleation...
In particle induced desorption-ionization mass spectrometry the strength of an
analyte's signal under a given set of bombardment conditions is usually considered to
be representative of the analytes relative surface activity. This rationale is generally
used to explain differences in the technique's sensitivity between and within various
classes of compound....
Nanotechnology products have long since made their way to markets around the world increasing the concerns about whether nanomaterials pose a risk to our environment or health. It has been suggested that engineered nanomaterial (ENM) with broad applications and rapid commercialization need better risk assessment and regulation. However, the refinement...
A more quantitative understanding of peptide entrapment and elution from otherwise protein-repellent polyethylene oxide (PEO) brush layers will provide direction for development of new strategies for drug storage and delivery. Here we describe criteria for peptide integration and structural change within the PEO brush, and discuss the reversibility of peptide...
Engineered capillary barriers typically consist of two layers of granular materials designed so that the contrast in sediment hydrologic properties and sloping interface retains infiltrating water in the upper layer. We report here on the results of two bench-top capillary barrier experiments, and associated modeling. These experiments were conducted to...
Nonionic surfactants are commonly used to stabilize proteins during upstream and downstream processing and drug formulation. Surfactants stabilize the proteins through two major mechanisms: (i) their preferential location at nearby interfaces, in this way precluding protein adsorption; and/or (ii) their association with protein into "complexes" that prevent proteins from interacting...