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Full-Text Articles in Physical Sciences and Mathematics

Just Add Water: Colonisation, Water Governance, And The Australian Inland, Leah M. Gibbs Sep 2013

Just Add Water: Colonisation, Water Governance, And The Australian Inland, Leah M. Gibbs

Leah Maree Gibbs

Water has played a key role in the development of the Australian inland and the nation. For European colonists, the dry and variable landscape challenged ideas about nature imported from northern temperate regions. I argue first, that colonists brought with them ideas for ordering nature and tools for transforming landscapes that led to inappropriate and destructive water management and the silencing of local voices and knowledge systems. Secondly, colonial patterns of ordering and transforming landscapes are ongoing, but new ways of governing water, which challenge colonialism, are emerging. In the first section of the paper I discuss colonial relationships with …


Evaluation Of Water Sanitation Options For Poultry Production, Pramir Maharjan Aug 2013

Evaluation Of Water Sanitation Options For Poultry Production, Pramir Maharjan

Graduate Theses and Dissertations

An evaluation of poultry farm water supplies was conducted to determine the value and impact of water system sanitation practices in commercial broiler houses on microbial levels. Water line cleaning between flocks using concentrated disinfectant solution before placing chicks reduced biofilms retained in the lines to a safe level. Occasional microbial surges were noticed during different points of flock grow-out period even when daily water sanitation was present indicating water is highly susceptible to microbial contamination. However, the daily water sanitation practice controlled the occasional microbial surges in water from sustaining and kept drinking water to a microbiologically acceptable level. …


Agriculture In A Water Scarce World, Allison Roberts, Amjad Assi, Bassel Daher, Men Li Jun 2013

Agriculture In A Water Scarce World, Allison Roberts, Amjad Assi, Bassel Daher, Men Li

Student Papers in Public Policy

According to the McKinsey report (2009), the world is facing a water scarcity challenge where agriculture is its predominant consumer. It accounts for approximately 3100 billion m3, or 71 percent of global water withdrawals today, and is expected to increase to 4500 billion m3 by 2030. This increase is due to a number of factors: growing population and the ever growing necessity to cater for its food needs, economic growth, the variability of precipitation trends and increase in global temperatures. In addition to the increase in water scarcity, the agricultural sector faces an enormous challenge of producing …


Impact Of Hydraulic Fracturing On Ground And Surface Water Resources, Reyna Schenck Jun 2013

Impact Of Hydraulic Fracturing On Ground And Surface Water Resources, Reyna Schenck

Natural Resources Management and Environmental Sciences

The following study examines hydraulic fracturing operations in the United States in relation to groundwater contamination, withdrawals of freshwater resources, and jurisdictional authority over the activity with the purpose of producing objective analysis of research findings. With a growing population and increasing energy needs, hydraulic fracturing is expanding across the nation, as is public concern over the risks to freshwater resources. Because of the difficulty in identifying non-point sources of water pollution, a lack of legitimate water samples representing baseline conditions, and incomplete lists of chemical additives used, study results are often inconclusive as to the correlation between hydraulic fracturing …


Oxygen Exchange During The Reaction Of Pocl3 And Water, Robert Clark, Robert Morrison, Andrew Thomas, Rebeca Alvarez, Paul Milham May 2013

Oxygen Exchange During The Reaction Of Pocl3 And Water, Robert Clark, Robert Morrison, Andrew Thomas, Rebeca Alvarez, Paul Milham

Robert Clark

To investigate O exchange during the reaction of POCl3 and water, natural abundance POCl3 was reacted with water highly enriched in 18O, and the resulting H3PO4 was isolated as KH2PO4. This reaction was conducted with and without tetrahydrofuran (THF) as a solvent, and was controlled in THF and violent in its absence. Approximately 5 x 10-4M aqueous solutions of the KH2PO4 were analyzed using electrospray ionization mass spectrometry, to estimate the proportions of the mass-clumped 16,17,18O isotope analogues of [H2PO4] -. During analysis, ~29% of [H2PO4] - dehydrated to [PO3]-, for which the proportions of the O isotope analogues were …


Catalytic Solar Water Splitting Inspired By Photosynthesis. Homogeneous Catalysts With A Mechanical ("Machine-Like") Action, Gerhard F. Swiegers, G Charles Dismukes, Leone Spiccia, Robin Brimblecombe, Annette Koo, Jun Chen, Gordon G. Wallace Mar 2013

Catalytic Solar Water Splitting Inspired By Photosynthesis. Homogeneous Catalysts With A Mechanical ("Machine-Like") Action, Gerhard F. Swiegers, G Charles Dismukes, Leone Spiccia, Robin Brimblecombe, Annette Koo, Jun Chen, Gordon G. Wallace

Gordon Wallace

Chemical reactions may be controlled by either: the minimum threshold energy that must be overcome during collisions between reactant molecules / atoms (the Activation Energy, Ea), or: the rate at which reactant collisions occur (the Collision Frequency, A) (for reactions with low Ea). Reactions of type (2) are governed by the physical, mechanical interaction of the reactants. Such mechanical processes are unusual, but not unknown in molecular catalysts. We examine the catalytic action and macroscopic properties of several abiological mechanical catalysts and show that they display distinct similarities to enzymes in general. An abiological model of the Photosystem II Water …


Conducting Polymers With Fibrillar Morphology Synthesized In A Biphasic Ionic Liquid/Water System, J.M. Pringle, Orawan Ngamna, Carol M. Lynam, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane Mar 2013

Conducting Polymers With Fibrillar Morphology Synthesized In A Biphasic Ionic Liquid/Water System, J.M. Pringle, Orawan Ngamna, Carol M. Lynam, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane

Gordon Wallace

The synthesis of poly(pyrrole), poly(terthiophene), and poly(3,4-ethylenedioxythiophene) with unusual fibrillar morphologies has been achieved by chemical polymerization in a biphasic ionic liquid/water system. Use of aqueous gold chloride as the oxidant, with the monomers dissolved in a hydrophobic ionic liquid, allows the polymerization to occur at the ionic liquid/water interface. The resultant conducting polymer fibrils are, on average, 50−100 nm wide and can be thousands of nanometers long. The polymers produced in this ionic liquid system are compared to those synthesized in a biphasic chloroform/water system.


Synthesis, Properties And Water Permeability Of Swnt Buckypapers, L J. Sweetman, L Nghiem, I Chironi, G Triani, Marc In Het Panhuis, St F. Ralph Feb 2013

Synthesis, Properties And Water Permeability Of Swnt Buckypapers, L J. Sweetman, L Nghiem, I Chironi, G Triani, Marc In Het Panhuis, St F. Ralph

Long D Nghiem

The ability of macrocyclic ligands to facilitate formation of dispersions of single-walled carbon nanotubes (SWNTs) was investigated using a combination of absorption spectrophotometry and optical microscopy. Vacuum filtration of aqueous dispersions containing SWNTs and various macrocyclic ligands (derivatised porphyrin, phthalocyanine, cyclodextrin and calixarene) afforded self-supporting membranes known as buckypapers. Microanalytical data and energy dispersive X-ray spectra were obtained for these buckypapers and provided evidence for retention of the macrocyclic ligands within the structure of the membranes. The electrical conductivities of the membranes varied between 30 ± 20 and 220 ± 60 S cm−1, while contact angle analysis revealed they all …


Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott Jan 2013

Short-Term Denitrification In The Metalimnion Of A Eutrophic Reservoir, Aki Kogo, Erin M. Grantz, Thad Scott

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Denitrification in metalimnetic water was examined under different conditions to determine how addition of nitrate (NO3 -) and particulate carbon (PC), aeration, and concentrations of nitrate affect denitrification. In the first experiment, water samples from a metalimnion were treated with different combinations of NO3 - and PC. Changes in excess N2 -N concentration for 10 days were measured using membrane inlet mass spectrometry (MIMS). The second experiment used the same treatments as the first experiment after aeration of water. Besides excess N2 -N concentrations, O2 concentrations were measured for 16 days. The third experiment examined how different initial concentrations of …