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2009

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Articles 5731 - 5760 of 7616

Full-Text Articles in Physical Sciences and Mathematics

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 Jan 2009

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 …

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Structural Revision Of Stemoburkilline From An E-Alkene To A Z-Alkene, Kwankamol Sastraruji, Stephen G. Pyne, Alison T. Ung, Pitchaya Mungkornawawakul, Wilford Lie, Araya Jatisatienr Jan 2009

Structural Revision Of Stemoburkilline From An E-Alkene To A Z-Alkene, Kwankamol Sastraruji, Stephen G. Pyne, Alison T. Ung, Pitchaya Mungkornawawakul, Wilford Lie, Araya Jatisatienr

Faculty of Science - Papers (Archive)

Semisynthesis studies starting from (11Z)-I',2'-didehydrostemofoline indicated that the known Stemona alkaloid stemoburkilline is the Z-isomer and not the E-isomer as initially reported. The semisynthesis involved conversion of (11Z)-1',2' -didehydrostemofoline to II(S), 12(S)-dihydrostemofoline followed by a stereoselective base-catalyzed ring-opening reaction to give (Z)-stemoburkilline. The same product was obtained using a similar synthetic protocol stariing from isostemofoline via a based-catalyzed ring-opening reaction of II (S), 12(R)-dihydrostemofoline. A re-examination of the crude root extracts of Stemona burkillii Prain and further NOE studies established stemoburkilline as the Z-isomer.

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Stemofoline Ethyl Acetate Solvate, Pitchaya Mungkornasawakul, Stephen G. Pyne, Alison T. Ung, Araya Jatisatienr, Anthony C. Willis Jan 2009

Stemofoline Ethyl Acetate Solvate, Pitchaya Mungkornasawakul, Stephen G. Pyne, Alison T. Ung, Araya Jatisatienr, Anthony C. Willis

Faculty of Science - Papers (Archive)

Crystals of the title compound, C2zH29NOs,C4HsOz, ([ systematic name: (2R,3R,5R,5aS,6R,8aR,9S)-(5Z)-5-[3-butyltetrah ydro-6-me thyl- 2,5-me thano-4,3 ,8a -[1] propan yl[3]ylidenefuro[ 3,2-j] [1,4]oxazepin-7( 5H)-ylidene ]-4-methoxy-3- methylfuran-2(5H)-one ethyl acetate solvate) were isolated from the root extracts of Stemona aphylla (Stemonaceae). The structure closely resembles those of stemofoline derivatives which have previously been reported. Intermolecular contacts are observed between some C-bonded H atoms and nearby 0 atoms, perhaps indicating weak interactions which could influence the packing of species within the unit cell.

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Alkaloids From The Roots Of Stemona Aphylla, Pitchaya Mungkornasawakul, Sukanda Chaiyong, Thanapat Sastraruji, Araya Jatisatienr, Chaiwat Jatisatienr, Stephen G. Pyne, Alison T. Ung, Jurgen Korth, Wilford Lie Jan 2009

Alkaloids From The Roots Of Stemona Aphylla, Pitchaya Mungkornasawakul, Sukanda Chaiyong, Thanapat Sastraruji, Araya Jatisatienr, Chaiwat Jatisatienr, Stephen G. Pyne, Alison T. Ung, Jurgen Korth, Wilford Lie

Faculty of Science - Papers (Archive)

Three known compounds, stemofoline, (2'S)-hydroxystemofoline, and (11Z)-1 ',2'-didehydrostemofoline, along with two new alkaloids, stemaphylline and stemaphylline-N-oxide, have been isolated from a root extract of Stemona aphylla. The structures of these alkaloids were determined on the basis of their spectroscopic data. The analysis of the crude dichloromethane extract by GC-MS in the ElMS mode showed the presence of alkaloids 1-4, the alkaloid 11, and stilbostemin R. The crude dichloromethane extract and 4 were tested for their comparative biological activities. The results of their acetylcholinesterase (AChE) inhibitory activities showed that the crude extract had higher activity than that of 4. The insecticidal …

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Synthesis And Applications Of Covalent Protein-Dna Conjugates, Patrick M. Schaeffer, Nicholas E. Dixon Jan 2009

Synthesis And Applications Of Covalent Protein-Dna Conjugates, Patrick M. Schaeffer, Nicholas E. Dixon

Faculty of Science - Papers (Archive)

Synthetic protein-DNA conjugates are valuable tools with applications in fields including nanobiotechnology, bioanalytical chemistry, and molecular diagnostics, and various synthetic methods for their production have been developed during the past three decades. The present article reviews current methodologies for the synthesis of covalent protein-DNA conjugates with particular focus on the regiospecificity and stoichiometry of these reactions.

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The Soils Of Kiritimati (Christmas) Island, Kiribati, Central Pacific: New Information And Comparison With Previous Studies, Colin D. Woodroffe, Robert John Morrison Jan 2009

The Soils Of Kiritimati (Christmas) Island, Kiribati, Central Pacific: New Information And Comparison With Previous Studies, Colin D. Woodroffe, Robert John Morrison

Faculty of Science - Papers (Archive)

No abstract provided.

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Investigations Of Electrochemical And Spectroelectrochemical Properties (Uv-Vis, Epr) Of Thiophene Trimer Derivatives Substituted With Phenylvinyl Groups., Pawel W. Wagner, Agnieszka Stolarczyk, Mariola Bartoszek, Mieczyslaw Lapkowski, David L. Officer, Keith C. Gordon, M Jadamiec, Wieslaw W. Sulkowski Jan 2009

Investigations Of Electrochemical And Spectroelectrochemical Properties (Uv-Vis, Epr) Of Thiophene Trimer Derivatives Substituted With Phenylvinyl Groups., Pawel W. Wagner, Agnieszka Stolarczyk, Mariola Bartoszek, Mieczyslaw Lapkowski, David L. Officer, Keith C. Gordon, M Jadamiec, Wieslaw W. Sulkowski

Faculty of Science - Papers (Archive)

The results of investigations concerning electrochem. properties of two thiophene trimers derivs. substituted with phenylvinyl groups {3'[(E)-2-phenylethenyl]-2,2':5',2"-thiophene (monomer A) and 4,4"-didecyloxy-3'[(E)-2-phenylethenyl]-2,2':5',2"-thiophene (monomer B)} and the products of their oxidn. were discussed. Electropolymns. of A and B monomers were carried out with use of cyclic voltammetry and electrochem. measurements were coupled in-situ with spectroscopic methods (UV-Vis, EPR). It was found that A monomer oxidized to oligomers sol. in dichloromethane while monomer B showed ability to form stable conductive polymer layers showing low-energy forbidden band (1.6 eV).

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Climate And Culture, Gordon R. Waitt, Andrew W. Gorman-Murray Jan 2009

Climate And Culture, Gordon R. Waitt, Andrew W. Gorman-Murray

Faculty of Science - Papers (Archive)

No abstract provided.

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Regional Development And Local Government: Three Generations Of Federal Intervention, Andrew H. Kelly, Brian Dollery, Bligh Grant Jan 2009

Regional Development And Local Government: Three Generations Of Federal Intervention, Andrew H. Kelly, Brian Dollery, Bligh Grant

Faculty of Science - Papers (Archive)

Contemporary Australian local government faces several daunting problems, not least escalating financial un-sustainability and local infrastructure depletion. The main response of the various state and territory governments has taken the form of a series structural reform programs, with a strong emphasis on forced amalgamation. However, widespread dissatisfaction with the consequences of these compulsory consolidation programs has led to a search for alternative policy solutions based largely on shared services and various types of regional co-operation between local councils. This paper seeks to place proposed ‘regional’ solutions to contemporary problems in historical perspective by providing a comparative account of three distinct …

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Were Environmental Or Demographic Factors The Driving Force Behind Middle Stone Age Innovations In Southern Africa?, Zenobia Jacobs, Richard G. Roberts Jan 2009

Were Environmental Or Demographic Factors The Driving Force Behind Middle Stone Age Innovations In Southern Africa?, Zenobia Jacobs, Richard G. Roberts

Faculty of Science - Papers (Archive)

Sir—Past human responses to environmental changes have long interested archaeologists. During the last glacial cycle, southern Africa experienced marked climatic fluctuations, as recorded in ice-core records from West and East Antarctica.

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Thermal Attributes Of Chrysomya Species, James F. Wallman, Leigh Nelson, Mark P. Dowton Jan 2009

Thermal Attributes Of Chrysomya Species, James F. Wallman, Leigh Nelson, Mark P. Dowton

Faculty of Science - Papers (Archive)

The correct identification of forensically important arthropods for post-mortem interval estimation is crucial, as the rate of larval development can vary substantially between species. The identification of forensically important blowflies of the genus Chrysomya (Diptera: Calliphoridae) may be hampered by their close morphological similarities, especially as immatures. The aim of this study was to establish whether genetically closely related blowfly species would share similar developmental profiles. This could permit the application of developmental data to a number of closely related species, including those for which thermodevelopmental studies are lacking. If Australian Chrysomya were found to share developmental profiles, identification of …

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Martellia And Associated Middle Ordovician Brachiopods From The Katkoyeh Formation, East-Central Iran, Ian G. Percival, Anthony J. Wright, Robert S. Nicoll, Mir Alireza Hamedi Jan 2009

Martellia And Associated Middle Ordovician Brachiopods From The Katkoyeh Formation, East-Central Iran, Ian G. Percival, Anthony J. Wright, Robert S. Nicoll, Mir Alireza Hamedi

Faculty of Science - Papers (Archive)

The palaeontology and stratigraphy of the Ordovician if Iran has been the subject of considerable research over the past 15 years, revealing biogeographically significant faunas whose affinities are shared both with peri-Gondwanian terranes and continental blocks. Documentation of the composition and ages of these faunas, many of which are still poorly known, is critical to constraining palaeogeographic reconstructions of the time.

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Trace Element Concentrations In Sediments From Kadavu Passage, Fiji, S Garimella, Robert John Morrison, Rajeev Lal, Ravin Deo Jan 2009

Trace Element Concentrations In Sediments From Kadavu Passage, Fiji, S Garimella, Robert John Morrison, Rajeev Lal, Ravin Deo

Faculty of Science - Papers (Archive)

No abstract provided.

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Solid-State And Solution-Phase Conformations Of Pseudoproline-Containing Dipeptides, James R. Cochrane, Nima Sayyadi, Danielle Skropeta, Peter Turner, Jack K. Clegg, Katrina A. Jolliffe Jan 2009

Solid-State And Solution-Phase Conformations Of Pseudoproline-Containing Dipeptides, James R. Cochrane, Nima Sayyadi, Danielle Skropeta, Peter Turner, Jack K. Clegg, Katrina A. Jolliffe

Faculty of Science - Papers (Archive)

The conformations of 14 threonine-derived pseudoproline-containing dipeptides (including four d-allo-Thr derivatives) have been investigated by NMR. In solution, the major conformer observed for all dipeptides is that in which the amide bond between the pseudoproline and the preceding amino acid is cis. For dipeptides in which the N-terminus is protected, the ratio of cis- to trans-conformers does not depend significantly on the side chain of the N-terminal amino acid, or the stereochemistry of the Thr residue. However, for dipeptides bearing a free N-terminus, there are significant differences in the ratios of cis- to trans-conformers depending on the side chain present. …

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The Lowest Singlet And Triplet States Of The Oxylallyl Diradical, David A. Hrovat, Stephen J. Blanksby, W C. Lineberger, Andrei Sanov, Luis Verlarde, Weston T. Borden, Daniel J. Goebbert, Adam J. Gianola, Xin Zhou, Stephanie M. Villano, Takatoshi Ichino Jan 2009

The Lowest Singlet And Triplet States Of The Oxylallyl Diradical, David A. Hrovat, Stephen J. Blanksby, W C. Lineberger, Andrei Sanov, Luis Verlarde, Weston T. Borden, Daniel J. Goebbert, Adam J. Gianola, Xin Zhou, Stephanie M. Villano, Takatoshi Ichino

Faculty of Science - Papers (Archive)

Photodetachment of the oxyallyl radical anion leads to formation of the oxyallyl diradical, an elusive transient molecule involved in many organic reactions. As described by W. C. Lineberger et al. in their Communication on page 8509 ff., the photoelectron spectrum reveals that the oxyallyl ground state is singlet and the lowest triplet state is only 55 meV higher in energy. The spectral profile indicates that the planar singlet state is the transition state for ringopening of cyclopropanone, whilst the CCC bending motion is activated upon photodetachment to the triplet state.

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Kam Die Kultur Aus Afrika?, Richard G. Roberts, Zenobia Jacobs Jan 2009

Kam Die Kultur Aus Afrika?, Richard G. Roberts, Zenobia Jacobs

Faculty of Science - Papers (Archive)

According to archaeological standards the Blombos Cave was on the south coast of Africa was a rather small dwelling. The footprint measures just over 50 square meters. But what the researchers unearthed in 13 cubic meters of cave floor was enough to revolutionize our knowledge of the history of the human mind. So-called modern behaviour was therefore on much earlier than previously thought. A team led by South African archaeologist Christopher Henshilwood of the African Heritage Research Institute in Cape Town, who also teaches at the University of Bergen (Norway), discovered in the last 15 years in the Blombos Cave …

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Fragmentation Pathways Of 2,3-Dimethyl-2,3-Dinitrobutane Cations In The Gas Phase, Martin Paine, Benjamin Kirk, Simon Ellis-Steinborner, Stephen J. Blanksby Jan 2009

Fragmentation Pathways Of 2,3-Dimethyl-2,3-Dinitrobutane Cations In The Gas Phase, Martin Paine, Benjamin Kirk, Simon Ellis-Steinborner, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

2,3-Dimethyl-2,3-dinitrobutane (DMNB) is an explosive taggant added to plastic explosives during manufacture making them more susceptible to vapour-phase detection systems. In this study, the formation and detection of gas-phase [M+H](+), [M+Li](+), [M+NH4](+) and [M+Na](+) adducts of DMNB was achieved using electrospray ionisation on a triple quadrupole mass spectrometer. The [M+H](+) ion abundance was found to have a strong dependence on ion source temperature, decreasing markedly at source temperatures above 50 degrees C. In contrast, the [M+Na](+) ion demonstrated increasing ion abundance at source temperatures up to 105 degrees C. The relative susceptibility of DMNB adduct ions toward dissociation was investigated …

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Identification Of Abundant Alkyl Ether Glycerophospholipids In The Human Lens By Tandem Mass Spectrometry Techniques, Roger J. Truscott, Jane Deeley, Todd W. Mitchell, Michael Thomas, Stephen J. Blanksby Jan 2009

Identification Of Abundant Alkyl Ether Glycerophospholipids In The Human Lens By Tandem Mass Spectrometry Techniques, Roger J. Truscott, Jane Deeley, Todd W. Mitchell, Michael Thomas, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

Previous studies have shown that the human lens contains glycerophospholipids with ether linkages. These lipids differ from conventional glycerophospholipids in that the sn-1 substituent is attached to the glycerol backbone via an 1-O-alkyl or an 1-O-alk-1'-enyl ether rather than an ester bond. The present investigation employed a combination of collision-induced dissociation (CID) and ozone-induced dissociation (OzID) to unambiguously distinguish such 1-O-alkyl and 1-O-alk-1'-enyl ethers. Using these methodologies the human lens was found to contain several abundant 1-O-alkyl glycerophos-phoethanolamines, including GPEtn(16:0e/9Z-18:1), GPEtn(11Z-18:1e/9Z-18:1), and GPEtn(18:0e/9Z-18:1), as well as a related series of unusual 1-O-alkyl glycerophosphoserines, including GPSer(16:0e/9Z-18:1), GPSer(11Z-18:1e/9Z-18:1), GPSer(18:0e/9Z-18:1) that to our …

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The Asaphid Trilobite Ogygites Collingwoodensis Reed, 1926 From The Late Ordovician Of New Zealand, Anthony J. Wright Jan 2009

The Asaphid Trilobite Ogygites Collingwoodensis Reed, 1926 From The Late Ordovician Of New Zealand, Anthony J. Wright

Faculty of Science - Papers (Archive)

The New Zealand asaphid trilobite Ogygites collingwoodensis is redescribed on the basis of the type material and new collections, and its assignment to Basiliella is confirmed. The species occurs with the trinucleid trilobite Incaia bishopi and graptolites indicative of the Nemagraptus gracilis zone (early Late Ordovician, early Sandbian/Gisbornian), mostly as disarticulated material in intensely bioturbated siltstone of the Douglas Formation. Comparison with coeval faunas is limited due to the low diversity of this fauna, but B. collingwoodensis shows some limited similarity to contemporaneous eastern Australian faunas, whereas Incaia also occurs in South America and South China.

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Impacts On A Threatened Bird Population Of Removals For Translocation, David Bain, Kristine French Jan 2009

Impacts On A Threatened Bird Population Of Removals For Translocation, David Bain, Kristine French

Faculty of Science - Papers (Archive)

The removal of individuals from a population may occur for several reasons and responses of populations will vary depending on the magnitude and nature of the removal and the life history of the species. An understanding of the effects of loss of individuals on these populations, and the mechanism of replacement, will be important to conservation. This maybe particularly important where wild individuals are used for the increasingly popular conservation strategy of translocation. During the recent translocation of the endangered eastern bristlebird (Dasyornis brachypterus), two monitoring sites were established in the wild source population, one where removals were to take …

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Fruit Availability And Utilisation By Grey-Headed Flying Foxes (Pteropodidae: Pteropus Poliocephalus) In A Human-Modified Environment On The South Coast Of New South Wales, Australia, Kerryn Parry-Jones, Kristine O. French, Emily Schmelitschek Jan 2009

Fruit Availability And Utilisation By Grey-Headed Flying Foxes (Pteropodidae: Pteropus Poliocephalus) In A Human-Modified Environment On The South Coast Of New South Wales, Australia, Kerryn Parry-Jones, Kristine O. French, Emily Schmelitschek

Faculty of Science - Papers (Archive)

Context. Extensive clearing and modi. cation of habitat is likely to change many facets of the environment including climate and regional food resources. Such changes may result in changes in behaviour in highly mobile fauna, such as flying foxes. Aims. The availability of fruit resources was examined to determine whether grey-headed flying foxes ( Pteropus poliocephalus) have feeding preferences related to habitat or dietary items, and whether human usage of the land around the colony site has affected the resources available. Methods. Fruit availability around a colony was monitored from December 2004 to March 2005. Night surveys and faecal analyses …

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A Multi-Centre Randomized, Open-Label Phase Ii Trial Of Erlotinib Plus Gemcitabine Or Gemcitabine Monotherapy As First-Line Therapy In Ecog Ps2 Patients With Chemo-Naive Advanced Nsclc, M. G. Michael, Michael Johnston, Stephen Clarke, Richard De Boer, Phillip R. Clingan, Nick Pavlakis Jan 2009

A Multi-Centre Randomized, Open-Label Phase Ii Trial Of Erlotinib Plus Gemcitabine Or Gemcitabine Monotherapy As First-Line Therapy In Ecog Ps2 Patients With Chemo-Naive Advanced Nsclc, M. G. Michael, Michael Johnston, Stephen Clarke, Richard De Boer, Phillip R. Clingan, Nick Pavlakis

Faculty of Science - Papers (Archive)

No abstract provided.

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Defining The Structural Basis Of Human Plasminogen Binding By Streptococcal Surface Enolase, Amanda J. Cork, Slobodan Jergic, Sven Hammerschmidt, Bostjan Kobe, Vijay Pancholi, Justin L.P. Benesch, Carol V, Robinson, Nicholas E. Dixon, J Andrew Aquilina, Mark J. Walker Jan 2009

Defining The Structural Basis Of Human Plasminogen Binding By Streptococcal Surface Enolase, Amanda J. Cork, Slobodan Jergic, Sven Hammerschmidt, Bostjan Kobe, Vijay Pancholi, Justin L.P. Benesch, Carol V, Robinson, Nicholas E. Dixon, J Andrew Aquilina, Mark J. Walker

Faculty of Science - Papers (Archive)

The flesh-eating bacterium group A Streptococcus (GAS) binds and activates human plasminogen, promoting invasive disease. Streptococcal surface enolase (SEN), a glycolytic pathway enzyme, is an identified plasminogen receptor of GAS. Here we used mass spectrometry (MS) to confirm that GAS SEN is octameric, thereby validating in silico modeling based on the crystal structure of S. pneumoniae -enolase. Site-directed mutagenesis of surface-located lysine residues (SENK252+255A, SENK304A, SENK334A, SENK344E, SENK435L and SEN434-435) was used to examine their roles in maintaining structural integrity, enzymatic function and plasminogen binding. Structural integrity of the GAS SEN octamer was retained for all mutants except SENK344E, as …

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Evaporation And Carbon Dioxide Exchange By Sugar Cane Crops, G Bryant, Travis A. Naylor, Stephen R. Wilson, O T Denmead, David W. Griffith, B.C.T. Macdonald, I. White Jan 2009

Evaporation And Carbon Dioxide Exchange By Sugar Cane Crops, G Bryant, Travis A. Naylor, Stephen R. Wilson, O T Denmead, David W. Griffith, B.C.T. Macdonald, I. White

Faculty of Science - Papers (Archive)

RECENT developments in water and carbon trading and biofuel production highlight the need to document the water and carbon balances of Australia’s cropping systems including sugarcane. This paper presents the results of studies of evaporation and CO2 exchange throughout the growing seasons of two sugarcane crops, a 1st ratoon crop at Murwillumbah where burnt-cane was practised and a 5th ratoon crop at Mackay where trash blanketing was employed. At both locations, a micrometeorological eddy covariance technique was employed to measure water vapour and CO2 exchange between crop and atmosphere and manual and automatic chambers to measure CO2 emission from the …

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Normal Stiffness Calibration Of Microfabricated Tri-Layer Conducting Polymer Actuators, Michael J. Higgins, Gursel Alici Jan 2009

Normal Stiffness Calibration Of Microfabricated Tri-Layer Conducting Polymer Actuators, Michael J. Higgins, Gursel Alici

Faculty of Science - Papers (Archive)

This paper reports on the stiffness characterization of microfabricated tri-layer conducting polymer (PPy) actuators. The rectangular, polypyrrole microactuators, which could operate both in aqueous and non-aqueous media, were fabricated using an excimer laser ablation technique that provided high throughput production and did not require cleanroom facilities. The microactuators were fixed at one end with electrical contacts and the other was end free to act as an electroactive microcantilever beam. An atomic force microscope (AFM) was used to measure the microactuator deflection under a range of normal forces applied by the AFM cantilever. A modified reference spring constant calibration method was …

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A Spectroscopic And Dft Study Of Thiophene-Substituted Metalloporphyrins As Dye-Sensitized Solar Cell Dyes, Sanjeev Gambhir, Keith C. Gordon, David L. Officer, Samual J. Lind Jan 2009

A Spectroscopic And Dft Study Of Thiophene-Substituted Metalloporphyrins As Dye-Sensitized Solar Cell Dyes, Sanjeev Gambhir, Keith C. Gordon, David L. Officer, Samual J. Lind

Faculty of Science - Papers (Archive)

A combination of density functional theory calculations, electronic absorption and resonance Raman spectroscopy has been applied to a series of beta-substituted zinc porphyrins to elucidate how the substituent affects the electronic structure of the metalloporphyrin and assign the nature of electronic transitions in the visible region. The use of conjugated beta substituents invokes a large perturbation to both the nature and energy of the frontier molecular orbitals and results in the generation of additional molecular orbitals from the parent metalloporphyrin species. A complicated electronic absorption spectra is observed which can be rationalised by an extension of Goutermans' four-orbital model. The …

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Electrochemical Afm : Understanding The Electromaterial-Cellular Interface, Amy Gelmi, Michael J. Higgins, Scott T. Mcgovern, Gordon G. Wallace Jan 2009

Electrochemical Afm : Understanding The Electromaterial-Cellular Interface, Amy Gelmi, Michael J. Higgins, Scott T. Mcgovern, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Organic conducting polymers are emerging as an exciting new class of biomaterial that can be used to enhance and control the growth of mammalian cells for tissue regeneration and engineering applications

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Molecular Water Oxidation Catalysts For Photoelectrochemical Cells, Robin Brimblecombe, Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia Jan 2009

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 …

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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 Jan 2009

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 …

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Assessment Of Eastern Bristlebird Habitat: Refining Understanding Of Appropriate Habitats For Reintroductions, Jack Baker Jan 2009

Assessment Of Eastern Bristlebird Habitat: Refining Understanding Of Appropriate Habitats For Reintroductions, Jack Baker

Faculty of Science - Papers (Archive)

The cryptic Eastern Bristlebird (Dasyornis brachypterus) is an endangered endemic of south-eastern Australia. Its distribution is highly fragmented with only two populations exceeding 500 individuals. Consequently, recovery planning includes translocation to increase the number of viable populations. The Eastern Bristlebird is typically found in low, dense vegetation. The species occurs in 26 different plant communities throughout its range, which suggests that it might be considered a habitat generalist. However, two studies based on aural surveys have demonstrated that it was conspicuous at heath-wood ecotones. Radiotracking was used to overcome reliance on aural surveys and to investigate the habitat of 12 …

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