The literature available on the silica content of herbaceous biomass, and its relative mobility in leaching/extraction systems, includes studies that have employed several different methods for silica quantification. This makes comparison of the data difficult. The objective of this thesis research was to determine the quantitative relationships between the measured...
Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic
primary production, and a higher fraction of organic matter export to the ocean
interior. Diatoms actively transport dissolved inorganic silicon into their cells, and
through the process of silicification (i.e. biogenic silica production) they build tough
and intricate...
This thesis is the consequence of a research effort undertaken by the School of Civil and Construction Engineering at Oregon State University and funded by the Oregon Department of Transportation (ODOT) and the Federal Highway Administration
(FHWA). The principal objective of the effort was to reduce the life cycle cost...
The diffusion of divalent nickel (Ni²⁺) from wet silica gels was investigated.
Silica gel is gaining interest as an encapsulation matrix for biological components.
The transport of biologically relevant species within the gel is determined by the
structural characteristics of the gel, which are in turn governed by synthesis
parameters....
In a search for designed materials that mimic those found in biological systems, combining polymers with inorganic materials in sol-gel chemistry processes has gained momentum in the research world since the 1990's. This work methodically investigated the properties of several related polymer-SiO₂ hybrids prepared by a simple methodology that could...
Dissolved silicic acid (Si(OH)4) and biogenic silica (BSiO2) concentrations were measured on four different cruises in the Southern Ocean along 1700 W from late October 1997 to mid-March 1998. These data were used to construct a vertically integrated Si budget in the surface layer from 58° to 68° S. Throughout...
There is significant interest in the fabrication of nano- and micro-structured silica with spatially ordered features, which exhibit enhanced optoelectronic properties with application to the next generation of display devices, semiconductors, and sensors. Currents methods of fabrication employ top down processes which use extremes of temperature, pressure, and power. There...
A new technique for determining the amount of opal in deep-sea
sediments of any age is described. Using a normative calculation, a
portion of the analytical silica concentration of sediments is subtracted
as non-biogenic in proportion to the concentration of aluminum in the
sample. The ratio of SiO₂:Al₂O₃ used to...
Infiltration of highly concentrated solutions into unsaturated sand is suspected to be affected by the liquid-gas interfacial tension between the resident water and that of the infiltrating solution. The wetting of non-porous solid surfaces by liquids is commonly quantified by contact angle measurements. However, it is well known that wettability...