Social and Behavioral Sciences Commons^™

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopologues: 1. Comparison Between Models And Observations, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Debra Wunch, Vanessa Sherlock, Nicholas M. Deutscher, David W. Griffith, Paul O. Wennberg, Kimberly Strong, Dan Smale, Emmanuel Mahieu, Sabine Barthlott, Frank Hase, Omar Garcia, Justus Notholt, Thorsten Warneke, Geoffrey Toon, David Sayres, Sandrine Bony, Jeonghoon Lee, Derek Brown, Ryu Uemura, Christophe Sturm

Faculty of Science - Papers (Archive)

[1] The goal of this study is to determine how H2O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H2O characteristics that are robust across data sets and that can be used to evaluate models. We evaluate …

Are Competitive Effects Of Native Species On An Invader Mediated By Water Availability?, Tanya J. Mason, Kristine French, Ken Russell

Faculty of Science - Papers (Archive)

Question: Climate change processes could influence the dynamics of biotic interactions such as plant competition, especially in response to disturbance phenomena such as invasional processes. Are competitive effects of native species on an invadermediated bywater availability?

Location: Glasshouse facility, New SouthWales, Australia.

Methods: We constructed competitive hierarchies for a representative suite of species from coastal dune communities that have been invaded by the Asteraceae shrub, bitou (Chrysanthemoides monilifera subsp. rotundata). We used a comparative phytometer approach, where the invader species was grown with or without a suite of native species in glasshouse trials. This was used to construct competition hierarchies …

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

Faculty of Science - Papers (Archive)

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 …

How Well Do Predators Adjust To Climate-Mediated Shifts In Prey Distribution? A Study On Australian Water Pythons, Beata Ujvari, Rick Shine, Thomas Madsen

Faculty of Science - Papers (Archive)

Climate change can move the spatial location of resources critical for population viability, and a species resilience to such changes will depend upon its ability to flexibly shift its activities away from no-longer-suitable sites to exploit new opportunities. Intuition suggests that vagile predators should be able to track spatial shifts in prey availability, but our data on water pythons (Liasis fuscus) in tropical Australia suggest a less encouraging scenario. These pythons undergo regular long-range (to .10 km) seasonal migrations to follow flooding-induced migrations by their prey (native dusky rats, Rattus colletti ). However, when an extreme flooding event virtually eliminated …

Specific Cellular Water Dynamics Observed In Vivo By Neutron Scattering And Nmr., Moeava Tehei, Marion Jasnin, Andreas Stadler, Giuseppe Zaccai

Faculty of Science - Papers (Archive)

Neutron scattering, by using deuterium labelling, revealed how intracellular water dynamics, measured in vivo in E. coli, human red blood cells and the extreme halophile, Haloarcula marismortui, depends on the cell type and nature of the cytoplasm. The method uniquely permits the determination of motions on the molecular length (Ba˚ ngstrøm) and time (pico- to nanosecond) scales. In the bacterial and human cells, intracellular water beyond the hydration shells of cytoplasmic macromolecules and membrane faces flows as freely as liquid water. It is not ‘‘tamed’’ by confinement. In contrast, in the extreme halophile archaeon, in addition to free and hydration …

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

Faculty of Science - Papers (Archive)

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 …

Book Review: "Troubled Waters: Confronting The Water Crisis In Australia's Cities" By Patrick Troy (Ed.), Leah M. Gibbs

Faculty of Science - Papers (Archive)

Troubled Waters is a collection of essays edited by Patrick Troy, Emeritus Professor and Visiting Fellow at the Fenner School of Environment and Society, Australian National University. The papers are contributed by a multidisciplinary group of authors, from the fields of economics, history, geography, environmental and social policy and law. As a result, the book does not present a single theoretical or methodological approach and in this regard it is refreshing. The book is published by the ANU E Press; a publisher that makes academic output from the ANU freely available from its website, as well as for purchase through …

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

Faculty of Science - Papers (Archive)

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 …

A Bio-Inspired Molecular Catalyst That Selectively Catalyzes Water Oxidation In Seawater, Without Significant Chlorine Formation, Robin Brimblecombe, G. Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia

Faculty of Science - Papers (Archive)

Most transport fuels are derived from fossil fuels, generate greenhouse gases, and consume significant amounts of water in the extraction, purification, and/or burning processes. The generation of hydrogen using solar energy to split water, ideally from sea water or other non-potable sources, could potentially provide an unlimited, clean fuel for the future. Solar, electrochemical water splitting typically combines a photoanode at which water oxidation occurs, with a cathode for proton reduction to hydrogen. In recent work we have found that a bioinspired tetra-manganese cluster catalyzes water oxidation at relatively low overpotentials (0.38 V) when doped into a Nafion proton conduction …

Molecular Water Oxidation Catalysts For Photoelectrochemical Cells, Robin Brimblecombe, Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia

Faculty of Science - Papers (Archive)

Photoelectrochemical cells that efficiently split water into oxygen and hydrogen, "the fuel of the future", need to combine robust water oxidation catalysts at the anode (2H(2)O -> O-2 + 4H(+) + 4e(-)) with hydrogen reduction catalysts at the cathode (2H(+) + 2e(-) -> H-2). Both sets of catalysts will, ideally, operate at low overpotentials and employ light-driven or light-assisted processes. In this Perspective article, we focus on significant efforts to develop solid state materials and molecular coordination complexes as catalyst for water oxidation. We briefly review the field with emphasis on the various molecular catalysts that have been developed and …

Spatial Ecology Of Hatchling Water Pythons (Liasis Fuscus) In Tropical Australia, Richard Shine, Thomas R. Madsen, Ligia Pizzatto, Gregory P. Brown

Faculty of Science - Papers (Archive)

Young snakes are rarely seen in the field and little is known about their habits. mostly because they are too small for radio-telemetry (the primary method for Studying snake spatial ecology). However, the offspring or some larger species can be fitted with transmitters and we investigated the spatial ecology and habitat use of ten hatchling water pythons (Liasis fuscus: Pythonidae) in the floodplain of the Adelaide River, tropical Australia. Patterns of habitat use in the late wet season and during the dry season were similar to those of adults tracked in the same vicinity in an earlier study. Soon after …

A Bio-Inspired Molecular Water Oxidation Catalyst For Renewable Hydrogen Generation: An Examination Of Salt Effects, Robin Brimblecombe, Miriam Rotstein, Annette Koo, G Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia

Faculty of Science - Papers (Archive)

Most transport fuels are derived from fossil fuels, generate greenhouse gases, and consume significant amounts of water in the extraction, purification, and/or burning processes. The generation of hydrogen using solar energy to split water, ideally from abundant water sources such as sea water or other non-potable sources, could potentially provide an unlimited, clean fuel for the future. Solar, electrochemical water splitting typically combines a photoanode at which water oxidation occurs, with a cathode for proton reduction to hydrogen. In recent work, we have found that a bioinspired tetra-manganese cluster catalyzes water oxidation at relatively low overpotentials (0.38 V) when doped …

Development And Application Of A System For The Analysis Of Atmospheric, Water And Sediment Nitrogen And Carbon, Ann Stavert, Stephen R. Wilson, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Eutrophication and climate change, key environmental concerns, are both linked to the carbon and nitrogen cycles hence the improved understanding of these cycles is essential. Currently, there is no system that simultaneously measures the fluxes of the three key gas phase products of nitrogen and carbon cycling (CO2, CH4 and N2O) in submerged ecosystems with hourly time resolution. A “Lake-in-a-box” (mesocosm) was developed in the laboratory which allowed the monitoring of key components of the carbon and nitrogen cycles within the air, water and sediments. The approach is automated, simple and time efficient and novel in its ability to examine …

Water Quality In The Wingecarribee Shire, Nsw, Glennys A. O'Brien, Mark R. O'Donnell, Adrian C. Hutton

Faculty of Science - Papers (Archive)

This paper reports on a water quality monitoring program carried out for Wingecarribee Shire Council between March 2002 and July 2004 by University of Wollongong staff and students. Initially 40 sites were sampled on four occasions over three months in a pilot program leading to the selection of sites and parameters for a two year program of monthly monitoring. A range of chemical, physical and biological parameters was measured including nutrients and faecal coliform bacteria on samples collected over the 26 approximately monthly sampling trips. Chlorophyll a, phaeophyton and blue-green algae were also determined over a shorter period. The sampling …

Water Quality Assessment - Issues From A Laboratory Management Perspective, Robert John Morrison, Mark R. O'Donnell, D. Springer

Faculty of Science - Papers (Archive)

This paper considers issues relating to the measurement of water quality parameters in the laboratory, especially an external (usually commercial) laboratory. Many organisations now use testing laboratories for water quality measurements, a process that has advantages and some limitations. The interaction between the testing laboratory and the organization requiring the data is crucial, and this paper looks at some aspects where a full appreciation of the role of each partner is important. These include limits of detection and reporting, measurement uncertainty, sample storage and preservation times, and various quality control procedures.

Water Quality In The Illawarra-South Coast Region Of New South Wales, Australia, Robert John Morrison, Mark R. O'Donnell

Faculty of Science - Papers (Archive)

Water quality is a serious environmental concern in the South Coast region of New South Wales as many aspects of human ecology and the economy are dependant on good water quality. Apart from drinking water for residents and visitors, tourism and agricultural productivity rely on good quality water. This paper presents an overview of general issues with regard to the development of water quality assessment procedures and programs, and discusses a number of issues considered important for the region. These include the impacts of increasing urbanisation, industrial activity (including mining), the potential wider use of groundwater and the improved management …

The Vibrational Spectra Of Protonated Water Clusters: A Benchmark For Self-Consistent-Charge Density-Functional Tight Binding, Haibo Yu, Qiang Cui

Faculty of Science - Papers (Archive)

Proton transfers are involved in many chemical processes in solution and in biological systems. Although water molecules have been known to transiently facilitate proton transfers, the possibility that water molecules may serve as the “storage site” for proton in biological systems has only been raised in recent years. To characterize the structural and possibly the dynamic nature of these protonated water clusters, it is important to use effective computational techniques to properly interpret experimental spectroscopic measurements of condensed phase systems. Bearing this goal in mind, we systematically benchmark the self-consistent-charge density-functional tight-binding �SCC-DFTB� method for the description of vibrational spectra …

An Alternative Approach To Coal Mine Site Water Management: A Case Study On West Cliff Colliery, Antony Volcich, Stephen A. Short, Adrian C. Hutton, Robert John Morrison

Faculty of Science - Papers (Archive)

The provision of water supply, its usage and discharge, are major concerns for all mines, often accounting for a significant portion of the daily running costs. To reduce these costs, mines will collect as much site runoff as possible, and recycle the water whenever economically feasible. The constant recycling of on-site waters can mean that, over time, the levels of salinity, acidity or alkalinity, or other contaminants may build up within the internal water management system to a point which may lead to problems with licensed discharge requirements. This project investigated the water quality at West Cliff Colliery, in order …

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

Faculty of Science - Papers (Archive)

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.

Effect Of Overlying Water Ph, Dissolved Oxygen, Salinity And Sediment Disturbances On Metal Release And Sequestration From Metal Contaminated Marine Sediments, Clare Atkinson, Dianne F. Jolley, Stuart L. Simpson

Faculty of Science - Papers (Archive)

Experiments were undertaken to examine the key variables affecting metal release and sequestration processes in marine sediments with metal concentrations in sediments reaching up to 86, 240, 700, and 3000mgkg1 (dry weight) for Cd, Cu, Pb and Zn, respectively. The metal release and sequestration rates were affected to a much greater extent by changes in overlying water pH (5.58.0) and sediment disturbance (by physical mixing) than by changes in dissolved oxygen concentration (38mgl1) or salinity (1545 practical salinity units). The physical disturbance of sediments was also found to release metals more rapidly than biological disturbance (bioturbation). The rate of oxidative …

An Assessment Of Five Australian Polychaetes And Bivalves For Use In Whole-Sediment Toxicity Tests: Toxicity And Accumulation Of Copper And Zinc From Water And Sediment, C K. King, M C. Dowse, S L. Simpson, D F. Jolley

Faculty of Science - Papers (Archive)

The suitability of two polychaete worms, Australonereis ehlersi and Nephtys australiensis, and three bivalves, Mysella anomala, Tellina deltoidalis, and Soletellina alba, were assessed for their potential use in whole-sediment toxicity tests. All species except A. ehlersi, which could not be tested because of poor survival in water-only tests, survived in salinities ranging from 18‰ to 34‰ during the 96-hour exposure period. No mortality was observed in any of the species exposed to sediment compositions ranging from 100% silt to 100% sand for 10 days, thus demonstrating the high tolerance of the five species to a wide range of sediment types. …

Charge-On-Spring Polarizable Water Models Revisited: From Water Clusters To Liquid Water To Ice, Haibo Yu, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

The properties of two improved versions of charge-on-spring �COS� polarizable water models (COS/G2 and COS/G3) that explicitly include nonadditive polarization effects are reported. In COS models, the polarization is represented via a self-consistently induced dipole moment consisting of a pair of separated charges. A previous polarizable water model (COS/B2), upon which the improved versions are based, was developed by Yu, Hansson, and van Gunsteren �J. Chem. Phys. 118, 221 �2003��. To improve the COS/B2 model, which overestimated the dielectric permittivity, one additional virtual atomic site was used to reproduce the water monomer quadrupole moments besides the water monomer dipole moment …

On The Transferability Of The Spcal Water Model To Biomolecular Simulation, Alice Glaettli, Chris Oostenbrink, Xavier Daura, Daan Geerke, Haibo Yu, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

We investigated the performance of the recently developed SPC/L model for liquid water, as a pure liquid, in binary mixtures with DMSO, and as a solvent model in a peptide folding simulation. Additionally, in order to test the compatibility with the GROMOS biomolecular force field, free energies of hydration of a set of representative compounds were computed. The results are compared to those for the well established SPC water model, which is generally used as a solvent model in conjunction with the GROMOS force field already for more than two decades. It turns out that as a pure liquid and …

Development Of A Simple, Self-Consistent Polarizable Model For Liquid Water, Haibo Yu, Tomas Hansson, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

The charge-on-spring method is used to develop a rigid, three-site, polarizable water model, a noniterative and a self-consistent version. In this method, the polarizability is taken into account by a variable separation of charges on selected polarizable centers. One of the pair of polarization charges resides on a polarizable center, while the other one is treated as an additional particle attached to the polarizable center by a parabolic restraint potential. The separation is calculated in response to the instantaneous electric field. We parametrized two models which are based on noniterative and self-consistent versions of the method, respectively. We computed several …

Thermoregulation In Juvenile Red Kangaroos (Macropus Rufus) After Pouch Exit: Higher Metabolism And Evaporative Water Requirements, Adam J. Munn, Terence J. Dawson

Faculty of Science - Papers (Archive)

The population dynamics of red kangaroos (Macropus rufus) in the Australian arid zone is tightly linked with environmental factors, which partly operate via the survival of juvenile animals. A crucial stage is the young-at-foot (YAF) stage when kangaroos permanently exit the pouch. We have examined the thermal biology of YAF red kangaroos during ages from permanent pouch exit until weaning. Over a wide range of environmental temperatures (ambient temperature [T-a] -5 degrees to 45 degreesC), YAF red kangaroos had a mass-specific metabolism that was generally twice that of adults, considerably higher than would be expected for an adult marsupial of …

Ventilatory Accommodation Of Oxygen Demand And Respiratory Water Loss In Kangaroos From Mesic And Arid Environments, The Eastern Grey Kangaroo (Macropus Giganteus) And The Red Kangaroo (Macropus Rufus), Terence J. Dawson, Adam J. Munn, Cyntina E. Blaney, Andrew Krockenberger, Shane K. Maloney

Faculty of Science - Papers (Archive)

We studied ventilation in kangaroos from mesic and arid environments, the eastern grey kangaroo (Macropus giganteus) and the red kangaroo (Macropus rufus), respectively, within the range of ambient temperatures (T-a) from -5 degrees to 45 degrees C. At thermoneutral temperatures (T-a = 25 degrees C), there were no differences between the species in respiratory frequency, tidal volume, total ventilation, or oxygen extraction. The ventilatory patterns of the kangaroos were markedly different from those predicted from the allometric equation derived for placentals. The kangaroos had low respiratory frequencies and higher tidal volumes, even when adjustment was made for their lower basal …