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2005

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Articles 4411 - 4440 of 5573

Full-Text Articles in Physical Sciences and Mathematics

An Automated Gis Method For Modeling Relative Wave Exposure Within Complex Reef-Island Systems: A Case Study Of The Great Barrier Reef, Marjetta L. Puotinen Jan 2005

An Automated Gis Method For Modeling Relative Wave Exposure Within Complex Reef-Island Systems: A Case Study Of The Great Barrier Reef, Marjetta L. Puotinen

Faculty of Science - Papers (Archive)

Patterns of wave energy play a significant role in shaping the long-term structure of coral reef communities worldwide. For example, sections of reefs have been shown to vary greatly in morphology (dominant size class, growth form) as coral colonies adapt in response to local-scale differences in the wave heights typically experienced. These differences result in zonation (crest, lagoon, and slope), producing characteristic growth forms and species assemblages that vary in their vulnerability to damage from waves (Done 1993). Those communities experiencing the greatest typical wave energy align themselves parallel to the water flow, adopt stream-lined forms and are usually smaller …

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Potential Application Of Solid Electrolyte P11oh In Ni/Mh Batteries, C.Y Wang, J. Sun, Hua-Kun Liu, S. X. Dou, D. Macfarlace, M. Forsyth Jan 2005

Potential Application Of Solid Electrolyte P11oh In Ni/Mh Batteries, C.Y Wang, J. Sun, Hua-Kun Liu, S. X. Dou, D. Macfarlace, M. Forsyth

Faculty of Science - Papers (Archive)

No abstract provided.

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Channel Pattern And Deltaic-Estuarine Process In The Indo-Pacific Region, Colin D. Woodroffe Jan 2005

Channel Pattern And Deltaic-Estuarine Process In The Indo-Pacific Region, Colin D. Woodroffe

Faculty of Science - Papers (Archive)

This paper explores the concept that deltaic-estuarine geomorphology is a function of the dominant processes. It has been traditional to recognize river, wave and tidal processes as the principal controls on the gross morphology of deltas. To a lesser extent, these processes are also recognized as significant controls on the shape of estuaries. The complex deltas of the Southeast Asian region contain active deltaic plains and often extensive abandoned deltaic plains which preserve an imprint of the processes which have shaped them. In northern Australia, where estuaries are more extensive than deltas, similar geomorphological features can be recognized and the …

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Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway Jan 2005

Illuminating Southeast Asian Prehistory : New Archaeological And Paleoanthropological Frontiers For Luminescence Dating, Richard G. Roberts, Michael J. Morwood, Kira E. Westaway

Faculty of Science - Papers (Archive)

Since the explorations of Alfred Russel Wallace and Eugène Dubois in the nineteenth century, Southeast Asia has been one of the world's focal points for studies of biogeography and biodiversity, human evolution and dispersal, environmental change, and the spread of culture, farming, and language. Yet despite its prominence, reliable chronologies are not available for many of the critical archaeological, evolutionary, and environmental turning points that have taken place in the region during the last 1.5 million years. In this paper, we discuss some of these chronological problems and describe how luminescence dating may help overcome them. "Luminescence dating" is a …

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Photoelectrochemical Cells Based On Inherently Conducting Polymers, Gordon G. Wallace, Chee O. Too, David L. Officer, Paul C Dastoor Jan 2005

Photoelectrochemical Cells Based On Inherently Conducting Polymers, Gordon G. Wallace, Chee O. Too, David L. Officer, Paul C Dastoor

Faculty of Science - Papers (Archive)

This review of photoelectrochemical cells (PECs) based on inherently conducting polymers (ICPs) deals with the mechanisms of operation and the various factors that influence the overall efficiency of PECs. The factors addressed include ICP composition and oxidation state, the use of nanostructured surfaces and interfaces, and the PEC electrolyte and redox mediator.

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Fractionation Of Sedimentary Arsenic From Port Kembla Harbour, Nsw, Australia, Glennys A. O'Brien, William E. Price, Bryan E. Chenhall, Muhammad Damris Jan 2005

Fractionation Of Sedimentary Arsenic From Port Kembla Harbour, Nsw, Australia, Glennys A. O'Brien, William E. Price, Bryan E. Chenhall, Muhammad Damris

Faculty of Science - Papers (Archive)

The binding of arsenic in sediments of the heavily industrialised Port Kembla Harbour, NSW, Australia, has been investigated. Both dredge and core samples have been used to develop a sieving/sequential extraction (SE) procedure. Dredge samples included oxic surficial and deeper anoxic sediment. The main core sample analysed was 18 cm deep, sliced at 2 cm intervals. Sediment was sieved to three size ranges (250 microm) and each of these was then subjected to a four step SE, sequentially solubilizing arsenic as ion exchangeable, 1 M HCl soluble, NH(2)OH.HCl soluble, and strong oxidising acid soluble. Concentrations of 50-500 mg As kg(-1) …

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Autopolymerization Of Pyrrole In The Presence Of A Host/Guest Calixarene, David A. Reece, Jennifer M. Pringle, Stephen F. Ralph, Gordon G. Wallace Jan 2005

Autopolymerization Of Pyrrole In The Presence Of A Host/Guest Calixarene, David A. Reece, Jennifer M. Pringle, Stephen F. Ralph, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Aqueous solutions containing pyrrole and calix-6-arenehexasulfonic acid were found to undergo polymerization in the absence of either a chemical oxidant or electrochemical oxidation. The product was an unstable colloidal suspension consisting of spherical polypyrrole particles measuring ≥500 nm in diameter. Conductivity measurements showed the material to be insulating, while cyclic voltammetry studies demonstrated that it was electroactive. Infrared spectroscopy and microanalysis confirmed that the polypyrrole produced was doped with calix-6-arenehexasulfonic acid. When the reaction was repeated using solutions containing stabilizing agents, stable colloidal dispersions were obtained. These were shown by both particle size analysis and transmission electron microscopy to contain …

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Environmental Effects Of Ozone Depletion And Its Interactions With Climate Change: Progress Report, 2004, A Andrady, P Aucamp, A Bais, C. Ballare, L Bjorn, J R. Bornman, M Caldwell, T Callaghan, A P. Cullen, D J. Erickson, F R. De Gruijl, D P. Hader, Mohammad Ilyas, G Kulandaivelu, H D. Kumar, J Longstreth, Richard L. Mckenzie, M Norval, H Redhwi, R C. Smith, Keith R. Solomon, B Sulzberger, Y Takizawa, Xiaoyan Tang, A H. Teramura, A Torikai, J C. Van Der Leun, Stephen R. Wilson, R C. Worrest, R. G. Zepp Jan 2005

Environmental Effects Of Ozone Depletion And Its Interactions With Climate Change: Progress Report, 2004, A Andrady, P Aucamp, A Bais, C. Ballare, L Bjorn, J R. Bornman, M Caldwell, T Callaghan, A P. Cullen, D J. Erickson, F R. De Gruijl, D P. Hader, Mohammad Ilyas, G Kulandaivelu, H D. Kumar, J Longstreth, Richard L. Mckenzie, M Norval, H Redhwi, R C. Smith, Keith R. Solomon, B Sulzberger, Y Takizawa, Xiaoyan Tang, A H. Teramura, A Torikai, J C. Van Der Leun, Stephen R. Wilson, R C. Worrest, R. G. Zepp

Faculty of Science - Papers (Archive)

The complexity of the linkages between ozone depletion, UV-B radiation and climate change has become more apparent.

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Carbanions: Formation, Structure And Thermochemistry, Stephen J. Blanksby, John H. Bowie Jan 2005

Carbanions: Formation, Structure And Thermochemistry, Stephen J. Blanksby, John H. Bowie

Faculty of Science - Papers (Archive)

This chapter deals with even-electron carbanions: their formation, structure and thermochemical properties in the gas phase. There are a number of excellent reviews already available on the chemistry of carbanions: these discuss in the main, reactivity and anion molecule chemistry.1-4 In this chapter we focus primarily on the formation, structure and thermochemistry of simple hydrocarbon anions while other chapters in this encyclopaedia cover the broader aspects of carbanion chemistry (see Volume 1, “Strained Ring and Highly Basic Carbanions” and this volume, Reactions of Organic Molecules with Organic Ions: “Reactions of Anions with Carbonyl Centres: C–C Bond Forming Reactions”, and Unimolecular …

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Does Mate Guarding Prevent Rival Mating In Snow Skinks? A Test Using Aflp, Mats M. Olsson, Beata Ujvari, Erik Wapstra, Thomas R. Madsen, Rick Shine, S. Bensch Jan 2005

Does Mate Guarding Prevent Rival Mating In Snow Skinks? A Test Using Aflp, Mats M. Olsson, Beata Ujvari, Erik Wapstra, Thomas R. Madsen, Rick Shine, S. Bensch

Faculty of Science - Papers (Archive)

We report on likely mixed paternity in a natural population of snow skinks (Niveoscincus mirolepidotus) from alpine Tasmania, Australia. This species is nonterritorial and males guard females after copulation, suggesting that guarding behavior has evolved to prevent rival mating of still-receptive females. To what degree does this mate-guarding prevent rival copulations? We sampled gravid females at random in the wild and looked for within-clutch mixed paternity among their offspring using amplified fragment length polymorphism (AFLP). Incorporating all visualized fragments, offspring band-sharing based on maternal bands was 0.94 (60.05, SD), whereas for paternal fragments it was 0.54 (60.46, SD). We then …

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Seasonal Variations Of Co And Hcn In The Troposphere Measured By Solar Absorption Spectroscopy Over Poker Flat, Alaska, Y Kasai, A. Kagawa, Nicholas B. Jones, A. Fujiwara, K. Seki, Y. Murayama, F Murcray Jan 2005

Seasonal Variations Of Co And Hcn In The Troposphere Measured By Solar Absorption Spectroscopy Over Poker Flat, Alaska, Y Kasai, A. Kagawa, Nicholas B. Jones, A. Fujiwara, K. Seki, Y. Murayama, F Murcray

Faculty of Science - Papers (Archive)

Tropospheric partial column abundances of CO and HCN have been retrieved from infrared solar spectra observed with a ground-based spectrometer at Poker Flat Alaska (65°N, 147°W) over the time period from 2000 to 2004. From these data we report the transpacific transport induced inter-annual variability of tropospheric CO over Poker Flat. This is the first report of solar infrared data from the Poker Flat station, where the geographical location of the site means that remote sensing measurements are sampling the transport of transpacific air parcels going to Northern America from Eastern Siberia and Asia. The five year time-span of the …

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Slag, Steel And Swamp: Perceptions Of Restoration Of An Urban Coastal Saltmarsh, Nicholas J. Gill Jan 2005

Slag, Steel And Swamp: Perceptions Of Restoration Of An Urban Coastal Saltmarsh, Nicholas J. Gill

Faculty of Science - Papers (Archive)

A community group, in conjunction with local government and industry, has been working on aquatic and terrestrial restoration at a Wollongong saltmarsh, previously diminished in size and degraded by harbour reclamation and an urban rubbish tip. Students evaluate restoration progress to date and devise some interesting potential directions.

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Transcending Nostalgia: Pastoralist Memory And Staking A Claim In The Land, Nicholas J. Gill Jan 2005

Transcending Nostalgia: Pastoralist Memory And Staking A Claim In The Land, Nicholas J. Gill

Faculty of Science - Papers (Archive)

The strength of Australian outback mythology in providing a blueprint for what Australian society, landscapes and history ought to be, lies at least partly in its ‘lack of specificity in time and space’, coupled with retrospect. Deborah Bird Rose has argued that such free-floating retrospect diverts attention from ‘here and now of our lives’, and militates against dealing with the consequences of Australia’s colonial past and present. The inland and north of Australia, the so-called ‘frontier’, in a spatial sense, are, and have been, places where optimistic non-indigenous assessments of land have been subject to regular appraisal and debate. They …

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Intercomparison Of O3 Profiles Observed By Sciamachy And Ground Based Microwave Instruments, M Palm, C V. Savigny, T Warneke, Voltaire A. Velazco, J Notholt, K Kunzi, J Burrows, O Schrems Jan 2005

Intercomparison Of O3 Profiles Observed By Sciamachy And Ground Based Microwave Instruments, M Palm, C V. Savigny, T Warneke, Voltaire A. Velazco, J Notholt, K Kunzi, J Burrows, O Schrems

Faculty of Science - Papers (Archive)

Ozone profiles retrieved from limb scattering measurements of the SCIAMACHY instrument based on the satellite ENVISAT are compared to ground-based low altitude resolution remote sensors. All profiles are retrieved using optimal estimation. Following the work of Rodgers and Connor (2003) the retrievals of the ground-based instruments are simulated using the SCIAMACHY retrieval. The SCIAMACHY results and the results of the ground-based microwave radiometer in Bremen and Ny A° lesund agree within the expected covariance of the intercomparison.

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Increased Northern Hemispheric Carbon Monoxide Burden In The Troposphere In 2002 And 2003 Detected From The Ground And From Space, L N. Yurganov, P Duchatelet, A V. Dzhola, D P. Edwards, F Hase, I Kramer, E Mahieu, J Mellqvist, J Notholt, P C. Novelli, A Rockmann, H E. Scheel, M Schneider, A Schulz, A Strandberg, R Sussmann, H Tanimoto, Voltaire A. Velazco, J Drummond, J Gille Jan 2005

Increased Northern Hemispheric Carbon Monoxide Burden In The Troposphere In 2002 And 2003 Detected From The Ground And From Space, L N. Yurganov, P Duchatelet, A V. Dzhola, D P. Edwards, F Hase, I Kramer, E Mahieu, J Mellqvist, J Notholt, P C. Novelli, A Rockmann, H E. Scheel, M Schneider, A Schulz, A Strandberg, R Sussmann, H Tanimoto, Voltaire A. Velazco, J Drummond, J Gille

Faculty of Science - Papers (Archive)

Carbon monoxide total column amounts in the atmosphere have been measured in the High Northern Hemisphere (30°- 90° N, HNH) between January 2002 and December 2003 using infrared spectrometers of high and moderate resolution and the Sun as a light source. They were compared to ground-level CO mixing ratios and to total column amounts measured from space by the Terra/MOPITT instrument. All these data reveal increased CO abundances in 2002-2003 in comparison to the unperturbed 2000-2001 period. Maximum anomalies were observed in September 2002 and August 2003. Using a simple two-box model, the corresponding annual CO emission anomalies (referenced to …

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Structure, Detrital Zircon U-Pb Ages And 40ar/39ar Geochronology Of The Early Palaeozoic Girilambone Group, Central New South Wales: Subduction, Contraction And Extension Associated With The Benambran Orogeny, Christopher L. Fergusson, C M Fanning, D. Phillips, Benjamin Ackerman Jan 2005

Structure, Detrital Zircon U-Pb Ages And 40ar/39ar Geochronology Of The Early Palaeozoic Girilambone Group, Central New South Wales: Subduction, Contraction And Extension Associated With The Benambran Orogeny, Christopher L. Fergusson, C M Fanning, D. Phillips, Benjamin Ackerman

Faculty of Science - Papers (Archive)

The Early Palaeozoic Cape River Metamorphics consist mainly of psammitic gneiss and schist and occur as an extensive linear belt at the western margin of the Charters Towers Province 200 km southwest of Townsville in the northern Tasmanides. A prominent foliation (S2) is the main structure in the belt and is associated with tight to isoclinal folds, subparallel mineral and intersection lineations, and boudinaged pods of vein quartz and pegmatite. In the southwest, the main foliation is a crenulation cleavage (S2) related to D2 deformation. It overprints steeply dipping foliation (S1) formed in …

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The Geological Context Of Middle Pleistocene Crater Lake Deposits And Fossil Birds At Ulupau Head, Oahu, Hawaiian Islands, Paul Hearty, H. F. James, S. L. Olson Jan 2005

The Geological Context Of Middle Pleistocene Crater Lake Deposits And Fossil Birds At Ulupau Head, Oahu, Hawaiian Islands, Paul Hearty, H. F. James, S. L. Olson

Faculty of Science - Papers (Archive)

Pleistocene lake deposits in Ulupau Crater on Oahu contain the oldest fossil bird remains known from the Hawaiian Islands. These fossils are important for documenting evolutionary rates in a variety of lineages of land and water birds from the islands. Detailed stratigraphic analysis reveals distinct cycles of deposition involving interbedded lacustrine deposits, colluvium, and paleosols. The volcanic basin was breached by marine erosion prior to the peak of the last interglaciation (marine isotope stage or ‘MIS’ 5e) over 125 ky ago, constraining the age of the lake sediments to the middle Pleistocene. The three cycles of deposition (Units III, IV, …

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Symbolic Revolutions And The Australian Archaeological Record, Mark W. Moore, Adam R. Brumm Jan 2005

Symbolic Revolutions And The Australian Archaeological Record, Mark W. Moore, Adam R. Brumm

Faculty of Science - Papers (Archive)

Australia was colonized by at least 40,000 bp and scientists agree that the continent was only ever occupied by anatomically and behaviourally modern humans. Australia thus offers an alternative early record for the archaeological expression of behavioural modernity. This review finds that the pattern of change in the Australian archaeological sequence bears remarkable similarity to the pattern from the Lower to Upper Palaeolithic in the Old World, a finding that is inconsistent with the 'symbolic revolution' model of the origin of modern behaviour. This highlights the need for archaeologists to rethink the implications of the various criteria and scales of …

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Development Of Watershed Management In New South Wales, Australia: A Coastal Perspective, Pedro I. J Fidelman, Robert John Morrison, Ron J. West Jan 2005

Development Of Watershed Management In New South Wales, Australia: A Coastal Perspective, Pedro I. J Fidelman, Robert John Morrison, Ron J. West

Faculty of Science - Papers (Archive)

Watershed management has become a prominent approach to natural resource management (NRM) in Australia and elsewhere. In the Australian State ofNew South Wales (NSW), catchment management - the NSW watershed management initiative - has been in place both in coastal and non-coastal areas for nearly two decades. In coastal areas, it is suggested that catchment management could play an important role in coastal and marine issues (NSW Coastcare et aI., 2004; Zann, 1996), as the Australia's coastal and marine environments have, in general, been affected by watershed-based activities (see e.g., Zann, 1996). Such a role would, however, require institutional changes, …

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Spatial Ecology Of Slatey-Grey Snakes (Stegonotus Cucullatus, Colubridae) On A Tropical Australian Floodplain, Gregory P. Brown, Richard Shine, Thomas Madsen Jan 2005

Spatial Ecology Of Slatey-Grey Snakes (Stegonotus Cucullatus, Colubridae) On A Tropical Australian Floodplain, Gregory P. Brown, Richard Shine, Thomas Madsen

Faculty of Science - Papers (Archive)

The extent, sequence, synchrony and correlates of diel displacements by animals can provide powerful insights into the ecological and social factors that shape an organism's day-to-day activities, but detailed data on spatial ecology are available for very few tropical taxa. Radiotelemetric monitoring of 25 slatey-grey snakes (Stegonotus cucullatus) on a floodplain in the Australian wet-dry tropics for periods of 40 to 355 d (mean=195 d, 136 locations per snake) provided extensive information on habitat use, movement patterns and home range size of these large slender-bodied colubrids. All radio-tracked animals were nocturnal, sheltering by day in soil cracks and …

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Prodromus Of Vertebrate Paleontology And Geochronology Of Bermuda, Storrs L. Olson, David B. Wingate, Paul J. Hearty, Frederick V. Grady Jan 2005

Prodromus Of Vertebrate Paleontology And Geochronology Of Bermuda, Storrs L. Olson, David B. Wingate, Paul J. Hearty, Frederick V. Grady

Faculty of Science - Papers (Archive)

Summary Pleistocene sea-level fluctuations were the primary determinant of geological deposition and biotic evolution on Bermuda. The island is composed of carbonate sand deposited on the eroded summit of a submarine volcano during ele- vated sea-levels of interglacial periods. A few vertebrate remains have been recovered directly from interglacial sandstones, mainly of mid-Pleistocene age. Glacial intervals are marked by red soils derived mainly from atmospheric dust. Vertebrate fossils of glacial age are not preserved at the surface and are known only from caves and fissure fills. Fossil faunas are known on Bermuda from the last two glacial episodes but none …

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Preliminary Results Of The Eip Project, Robert G. Bednarik, Giriraj Kumar, Alan Watchman, Richard G. Roberts Jan 2005

Preliminary Results Of The Eip Project, Robert G. Bednarik, Giriraj Kumar, Alan Watchman, Richard G. Roberts

Faculty of Science - Papers (Archive)

The primary rationale of the Early Indian Petroglyphs Project is to investigate claims of the occurrence of Lower Palaeolithic petroglyphs in central regions of India. Other purposes of this multifacetted research project are to provide new data for the chronology of the Middle and Late Pleistocene hominin history of India; to introduce scientific methods of rock art dating in this country; and to investigate its Lower Palaeolithic stone tool industries. This project, a collaboration of Indian and Australian researchers, was commenced in 2001. It involves archaeological excavations, a range of analytical studies and intensive field surveys, and it will continue …

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Effects Of Javan Rusa Deer (Cervus Timorensis) On Native Plant Species In The Jibbon-Bundeena Area, Royal National Park, New South Wales, David Keith, Belinda Pellow Jan 2005

Effects Of Javan Rusa Deer (Cervus Timorensis) On Native Plant Species In The Jibbon-Bundeena Area, Royal National Park, New South Wales, David Keith, Belinda Pellow

Faculty of Science - Papers (Archive)

A reconnaissance survey and exclosure experiment were carried out to examine the effects of Javan rusa deer on native flora and vegetation in Royal National Park on the southern outskirts of Sydney, Australia. Of 78 native plant species examined during the survey, only nine showed no evidence of vertebrate herbivory or physical damage and the majority of these plants were ferns and sedges. The other 69 species showed effects that included defoliation (young and/or old leaves), removal of shoots, bark-stripping, stem breakages and destruction or consumption of reproductive material. These effects varied in severity between species and from place to …

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Synthesis Of Carbocyclic Hydantocidins Via Regioselective And Diastereoselective Phosphine-Catalyzed [3+2]-Cycloadditions To 5-Methylenehydantoins, Tien Quoc Pham, Stephen G. Pyne, Brian W. Skelton, Allan H. White Jan 2005

Synthesis Of Carbocyclic Hydantocidins Via Regioselective And Diastereoselective Phosphine-Catalyzed [3+2]-Cycloadditions To 5-Methylenehydantoins, Tien Quoc Pham, Stephen G. Pyne, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

The phosphine-catalysed [3+2]-cycloaddition of 5-methylenehydantoins 4 with the ylides 5, derived from addition of tributylphosphine to the 2-butynoic acid derivatives, 6a-d, gives spiro-heterocyclic products. The camphor sultam derivative 6b gives optically active products. Noteable was that the ylides derived from ethyl 2-butynoate and the 3-(2-butynoyl)-1,3-oxazolidin-2-one derivatives 6c and 6d gave spiro-heterocyclic products with reverse regioselectivities. The N,N-dibenzylprotected cycloadduct has been converted to carbocyclic hydantocidin and 6,7-diepi-carbocyclic hydantocidin.

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Confirmation Of The Structure Of Oxystemokerrin By Single Crystal X-Ray Structural Analysis And A Proposed Biosynthesis, Pitchaya Mungkornasawakul, Hayden Matthews, Alison T. Ung, Stephen G. Pyne, Araya Jatisatienr, Wilford Lie, Brian W. Skelton, Allan H. White Jan 2005

Confirmation Of The Structure Of Oxystemokerrin By Single Crystal X-Ray Structural Analysis And A Proposed Biosynthesis, Pitchaya Mungkornasawakul, Hayden Matthews, Alison T. Ung, Stephen G. Pyne, Araya Jatisatienr, Wilford Lie, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

The crystal structure of the pentacyclic Stemona alkaloid oxystemokerrin (2), isolated from the roots of Stemona kerrii, is reported, confirming the structure proposed for this compound in a contemporaneous spectroscopic study. This compound is a diastereomer of stemocurtisinol (3), whose structure we have recently reported from S. curtisii, also confirmed by a single-crystal X-ray study. These alkaloids have opposite configurations at C-4 and C-19. A possible biosynthetic pathway for the biosynthesis of 2 and 3 is proposed.

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Mechanisms Of Climate Variability, Edward A. Bryant Jan 2005

Mechanisms Of Climate Variability, Edward A. Bryant

Faculty of Science - Papers (Archive)

Climatic hazards originate with the processes that move air across the Earth's surface due to differential heating and cooling. Surprisingly, examination of these processes has focused upon heating at the tropics and downplayed the role of cold air masses moving out of polar regions due to deficits in the radiation balance in these latter regions. Fluctuations – in the intensity of pulses of cold air moving out of polar regions or of heating at the equator – and the location of the interaction between these cold and warm air masses, are crucial factors in determining the magnitude, frequency, and location …

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A New Species Of Goodenia (Goodeniaceae) From Nocoleche Nature Reserve, Far Western Plains, New South Wales, Belinda J. Pellow, John L. Potter Jan 2005

A New Species Of Goodenia (Goodeniaceae) From Nocoleche Nature Reserve, Far Western Plains, New South Wales, Belinda J. Pellow, John L. Potter

Faculty of Science - Papers (Archive)

Goodenia nocoleche was cultivated in sediment collected from a freshwater temporary wetland in Nocoleche Nature Reserve. Here it is newly described and illustrated with additional notes on its ecology.

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Phytochemical Studies On Stemona Plants: Isolation Of Stemofoline Alkaloids, Thanapat Sastraruji, Araya Jatisatienr, Stephen G. Pyne, Alison T. Ung, Wilford Lie, Morwenna C. Williams Jan 2005

Phytochemical Studies On Stemona Plants: Isolation Of Stemofoline Alkaloids, Thanapat Sastraruji, Araya Jatisatienr, Stephen G. Pyne, Alison T. Ung, Wilford Lie, Morwenna C. Williams

Faculty of Science - Papers (Archive)

Six new stemofoline alkaloids, (2‘R)-hydroxystemofoline (5), (3‘R)-stemofolenol (6), (3‘S)-stemofolenol (7), 1‘,2‘-didehydrostemofoline-N-oxide (8), the first C19 stemofoline alkaloid, methylstemofoline (9), and the first glycosidated Stemona alkaloid, stemofolinoside (10), and three known alkaloids, (2‘S)-hydroxystemofoline (2), (11Z)-1‘,2‘-didehydrostemofoline (3), and (11E)-1‘,2‘-didehydrostemofoline (4), have been isolated from a root extract of an unidentified Stemona species. The structure and relative configuration of these new alkaloids have been determined by spectral data interpretation and …

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Synthesis Of 2-Azaspiro[4.4]Nonan-1-Ones Via Phosphine-Catalysed [3+2]-Cycloadditions, Sarah Yong, Morwenna C. Williams, Stephen G. Pyne, Alison T. Ung, Brian W. Skelton, Allan H. White, P. Turner Jan 2005

Synthesis Of 2-Azaspiro[4.4]Nonan-1-Ones Via Phosphine-Catalysed [3+2]-Cycloadditions, Sarah Yong, Morwenna C. Williams, Stephen G. Pyne, Alison T. Ung, Brian W. Skelton, Allan H. White, P. Turner

Faculty of Science - Papers (Archive)

The phosphine-catalysed [3+2]-cycloaddition of the 2-methylene γ-lactams 4 and 5 and the acrylate 6 with the ylides derived from the ethyl ester, the amide or the chiral camphor sultam derivative of 2-butynoic acid (7a-c) give directly, or indirectly after reductive cyclization, spiro-heterocyclic products. The acid 32 underwent Curtius rearrangement and then acid hydrolysis to give two novel spiro-cyclic ketones, 41 and 42.

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The History Of Aridity In Australia: Chronological Developments, Ed Rhodes, John Chappell, Toshiyuki Fujioka, Kat Fitzsimmons, John Magee, Max Aubert, Dolan Hewitt Jan 2005

The History Of Aridity In Australia: Chronological Developments, Ed Rhodes, John Chappell, Toshiyuki Fujioka, Kat Fitzsimmons, John Magee, Max Aubert, Dolan Hewitt

Faculty of Science - Papers (Archive)

Desert dune-fields are quintessential features of arid landscapes. During arid phases in the recent geological past, such as the global last glacial maximum (LGM) at around 20,000 years ago, many parts of Australia experienced significant sand movement, with sand migrating down-wind and forming linear dunes. Sand entrainment and deposition is controlled by vegetative surface stabilisation, wind speed and direction, which in turn are controlled by regional climate and local factors including ground-water levels. Climate also affects sand supply, through its effects on erosion in the source areas and transport to the dune-building areas.

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