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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Exploring solvent properties of high pressure carbon dioxide via computer simulation

Lee, Kenneth Michael 28 August 2008 (has links)
Not available / text
32

Stabilization of colloidal dispersions in supercritical carbon dioxide

Dickson, Jasper Lane 28 August 2008 (has links)
Not available / text
33

The leaching of vanadium(V) in soil due to the presence of atmospheric carbon dioxide and ammonia

Mandiwana, KL, Panichev, N 24 March 2009 (has links)
The natural leaching of vanadium(V) with CO2 from soil-water in the presence of ammonia, a known precursor to atmospheric aerosols, has been tested by bubbling carbon dioxide through soil suspension with varying amount of ammonia. It was found that the leaching of V(V) is enhanced in the presence of ammonia. From the results of the investigation, it could be concluded that atmospheric CO2 in the presence of ammonia (the only atmospheric gas that increases the pH of soil-water) could naturally leach V(V) from soil. Furthermore, it was also shown that the presence of (NH4)2CO3 in soil could enhance the leaching of toxic V(V) species thereby making it bioavailable for both plants and animals.
34

Construction of a carbon dioxide laser and preliminary test for reduction reaction with hydrogen

Turner, Michael Kent, 1944- January 1970 (has links)
No description available.
35

CO2-Triggered Switchable Solvent Systems and Their Applications

Phan, Lam 27 October 2008 (has links)
This thesis begins with the introduction of solvents and their classification. The two solvent system studied here are switchable polarity solvents (SPS). A switchable polarity solvent is a liquid where its polarity can change between two forms by a trigger. These two solvent systems have several similar characteristics. First, they both require CO2 as the switching agent, which can be switched back by its removal with heat or N2. The first project is the continuation of previous work with using an amidine and alcohol mixtures as a switchable polarity solvent. The second project was the development of a new switchable polarity solvent that is based on the reaction of a secondary amine with CO2. Both solvent systems are fully characterized by many analytical techniques and examples of applications in chemical reaction and separation are outlined. The final project involves using these solvent systems, among others, in the separation of soybean oil. The aim was to use SPS technology to extract soybean oil from the bean flakes, and then separate the oil from the extracting solvent. / Thesis (Master, Chemistry) -- Queen's University, 2008-02-07 15:21:31.499
36

CO₂ -expanded liquids as environmentally benign process solvents

West, Kevin Neal 05 1900 (has links)
No description available.
37

Looking for Permeability: Mass and Heat Flow Assessment Using High Resolution soil CO₂Flux Surveys within the Taupo Volcanic Zone, New Zealand

Bloomberg, Simon January 2012 (has links)
Soil CO2 flux (φCO₂) has increasingly become important as a global exploration and monitoring tool in geothermal and volcanic fields. As CO₂ is the second most abundant gas in magma-hydrothermal systems, its study is vital for the location or management of those systems. Often one of the only surface expressions is the diffuse gas flux streaming through the soil zone. This thesis reports the investigations into heat and mass at the Rotokawa geothermal field’s thermal area, and White Island volcano’s crater floor hydrothermal system. Surface measurements were taken at high spatial resolution across the fields in a large sampling campaign during the summers of 2010/2011 and 2011/2012. A large dataset was built up which allowed for greater accuracy during geospatial modelling. The models are 2d pixel plots of the soil gas flux and temperature and are used to estimate values of heat and mass flow for the respective magma-hydrothermal systems. Both field areas have a large anomalous diffuse gas flux through the soil zone and related conductive heat flow anomaly, which indicates relative permeability from the source to the surface in these areas. That the rising fluids from the deep source can be sampled at the surface simply is a powerful tool for the exploration and management of these systems. Rotokawa has a diffuse gas release of over 600 t d⁻¹ and an associated heat flow through soil of 37 MWt while White Island has a diffuse gas release of 116 t d⁻¹ and 19.5 MWt of heat flow through the soil. Translating these values to total heat and mass flow values: Rotokawa has a mass flow 125 kg s⁻¹ and a heat flow of 314 MWt and White Island’s crater floor has a mass flow of 100 kg s⁻¹ and a heat flow of 22 MWt. Fluid flow pathways are mapped from the surface and show arcuate and hot spot spatiality, controlled by fault related permeability and structure. soil gas and temperature surveying elucidates Shallow structures that otherwise may have been hidden from status quo surface mapping. The method used in this study is applicable to both known thermal areas and blind thermal areas by addressing not only the flux but also the nature of the soil gases. Further study of White Island has found more evidence for the existence of seawater infiltration of the crater magma-hydrothermal system.
38

Diffraction of neutrons by gas molecules.

Alcock, Norman Zinkan. January 1949 (has links)
A monokinetic beam of neutrons (0.07 e.v.) has been scattered by a gas, and the angular dependence of scattering measured over the range 0° to 90°. This isbelieved to be the first measurement of neutrons diffracted by gas molecules. The experiments were performed with a modified neutron crystal spectrometer using a beam of neutronsfrom the Chalk River pile. The gases studied, CO2 and O2, were at room temperature and approximately 60 atmospheres pressure. Observed intensity distributions are compared with calculated patterns. The latter are based on classical interference theory, so take no account of inelasticscattering. Good angular agreement of interference peaks is found for both gases. Good relative intensity agreement is found for 02, but the measured intensity for CO2 falls below thecalculated curve at small angles. A possible reason for this is given.
39

High peak power, pulsed, planar waveguide CO2 lasers

Murray, Paul R. January 2000 (has links)
No description available.
40

Water, Energy and Carbon Dioxide Exchange of a Riparian Mesquite Woodland

Edwards, Eric Alan. January 2002 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references (leaves 100-104).

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