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Full-Text Articles in Physical Sciences and Mathematics

Combining Mbr And Nf/Ro Membrane Filtration For The Removal Of Trace Organics In Indirect Potable Water Reuse Applications, William Price, Nichanan Tadkaew, Long Nghiem, Stuart Khan, Abdulhakeem Alturki, James Mcdonald Dec 2012

Combining Mbr And Nf/Ro Membrane Filtration For The Removal Of Trace Organics In Indirect Potable Water Reuse Applications, William Price, Nichanan Tadkaew, Long Nghiem, Stuart Khan, Abdulhakeem Alturki, James Mcdonald

Long D Nghiem

The aim of this study was to demonstrate the complementarities of combining membrane bioreactor (MBR) treatment with nanofiltration (NF) or reverse osmosis (RO) membrane filtration for the removal of trace organic contaminants for potential indirect potable water recycling applications. Four commercially available NF/RO membranes, namely NF270, NF90, BW30 and ESPA2, were selected for this investigation. Challenge tests were conducted with 40 trace organic compounds at concentrations of approximately 2 ng/L in initial wastewater solutions using a laboratory scaleMBRsystem and a cross-flow NF/RO rig. The results suggest that the MBR system effectively removes hydrophobic and biodegradable trace organic compounds. The adsorption …


Reactions Of Simple And Peptidic Alpha-Carboxylate Radical Anions With Dioxygen In The Gas Phase, Tony Ly, Benjamin B. Kirk, Pramesh I. Hettiarachchi, Berwyck L. Poad, Adam J. Trevitt, Gabriel Da Silva, Stephen J. Blanksby Oct 2012

Reactions Of Simple And Peptidic Alpha-Carboxylate Radical Anions With Dioxygen In The Gas Phase, Tony Ly, Benjamin B. Kirk, Pramesh I. Hettiarachchi, Berwyck L. Poad, Adam J. Trevitt, Gabriel Da Silva, Stephen J. Blanksby

Stephen Blanksby

α-Carboxylate radical anions are potential reactive intermediates in the free radical oxidation of biological molecules (e.g., fatty acids, peptides and proteins). We have synthesised well-defined α-carboxylate radical anions in the gas phase by UV laser photolysis of halogenated precursors in an ion-trap mass spectrometer. Reactions of isolated acetate (CH2CO 2-) and 1-carboxylatobutyl (CH3CH 2CH2CHCO2-) radical anions with dioxygen yield carbonate (CO3-) radical anions and this chemistry is shown to be a hallmark of oxidation in simple and alkyl-substituted cross-conjugated species. Previous solution phase studies have shown that Cα-radicals in peptides, formed from free radical damage, combine with dioxygen to form …


A Petrological, Mineralogical And Geochemical Analysis Of Listwaenite Alteration At Spring Creek Bingara In The Great Serpentinite Belt, New England, Nsw, E Holcroft, Solomon Buckman, I Neuss Sep 2012

A Petrological, Mineralogical And Geochemical Analysis Of Listwaenite Alteration At Spring Creek Bingara In The Great Serpentinite Belt, New England, Nsw, E Holcroft, Solomon Buckman, I Neuss

Solomon Buckman Dr.

No abstract provided.


Silica-Carbonate (Listwanites) Related Gold Mineralisation Associated With Epithermal Alteration Of Serpentinite Bodies, Solomon Buckman, P Ashley Sep 2012

Silica-Carbonate (Listwanites) Related Gold Mineralisation Associated With Epithermal Alteration Of Serpentinite Bodies, Solomon Buckman, P Ashley

Solomon Buckman Dr.

No abstract provided.


Using Lidar To Assess The Effect Of Fire And Floods On Upland Peat Bogs, Waterfall Gully, Mount Lofty Ranges, South Australia, Javier Leon Patino, Solomon Buckman, Robert P. Bourman, Rowena Morris, Katherine C. Brownlie Sep 2012

Using Lidar To Assess The Effect Of Fire And Floods On Upland Peat Bogs, Waterfall Gully, Mount Lofty Ranges, South Australia, Javier Leon Patino, Solomon Buckman, Robert P. Bourman, Rowena Morris, Katherine C. Brownlie

Solomon Buckman Dr.

A flood exceeding the 100 year average recurrence interval in November 2005 led to the failure of an upland peat bog in Waterfall Gully. The area is prone to severe bushfire and flood events and the control dam at the base of First Falls was filled with sediment sourced from Wilson Bog. A resistant quartzite bar at Fourth Falls has formed a natural constriction point against which burnt logs and debris have collected following previous fire events forming a natural dam resulting in sediment/peat accumulation upstream. The failure of the bog was inevitable as the vegetative material in the log-jam …


The Dirt On Assessing Post-Fire Erosion In The Mount Lofty Ranges: Comparing Methods, Rowena H. Morris, Solomon Buckman, Paul Connelly, Deirdre Dragovich, Bertram Ostendorf, Ross A. Bradstock Sep 2012

The Dirt On Assessing Post-Fire Erosion In The Mount Lofty Ranges: Comparing Methods, Rowena H. Morris, Solomon Buckman, Paul Connelly, Deirdre Dragovich, Bertram Ostendorf, Ross A. Bradstock

Solomon Buckman Dr.

Land managers are required to assess a range of environmental attributes prior to and after prescribed burning. Current environmental assessments vary depending on the organisation involved and the existing information about localised soil erosion. Auditing successful environmental assessments requires ongoing field monitoring to evaluate whether the magnitude and extent of predicted post-fire impacts are comparable. The impacts of post-fire erosion were assessed by the authors using the techniques of water sampling, sediment traps, erosion pins, laser scanning, photogrammetry and visual field assessment. Each data collecting method varies in its spatial and temporal reach in terms of monitoring landscape changes in …


Soil Geochemistry And Pathfinder Element Distribution Associated With The Hillgrove Antimony-Gold-Tungsten Deposit, New England Orogen, Nsw, R Ellsmore, Solomon Buckman, C Simpson Sep 2012

Soil Geochemistry And Pathfinder Element Distribution Associated With The Hillgrove Antimony-Gold-Tungsten Deposit, New England Orogen, Nsw, R Ellsmore, Solomon Buckman, C Simpson

Solomon Buckman Dr.

No abstract provided.


Accordion Vs. Quantum Tectonics: Insights Into Continental Growth Processes From The Paleozoic Of Eastern Gondwanan, Jonathan C. Aitchison, Solomon Buckman Sep 2012

Accordion Vs. Quantum Tectonics: Insights Into Continental Growth Processes From The Paleozoic Of Eastern Gondwanan, Jonathan C. Aitchison, Solomon Buckman

Solomon Buckman Dr.

The Early Paleozoic Lachlan Fold Belt of eastern Australia is widely regarded as an ancient convergent plate margin beneath which paleo-Pacific (Panthalassic) oceanic lithosphere was continuously subducted. It is cited as the type example of a retreating accretionary orogeny. However, sandstone compositions, the sedimentological nature and timing of chert accumulation and overall stratigraphic architecture are not necessarily consistent with this model. We suggest an alternative explanation for growth of Gondwanan continental margin. Oceanic lithosphere outboard of the passive Gondwana continental margin was subducted beneath an extensive intra-oceanic island arc that now crops out as an allochthonous element (Macquarie arc) within …


Managing Our Waste, Faisal Ibney Hai Aug 2012

Managing Our Waste, Faisal Ibney Hai

Faisal I Hai

No abstract provided.


A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali Aug 2012

A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali

Faisal I Hai

This study has analyzed the generation and characteristics of solid waste in Dhaka city, along with the associated environmental impacts and existing solid waste management practices. Special focus was given on the effect of composting on final disposal of solid waste and effect of landfill site location on transportation cost. An estimate of the future generation rate indicates that the present generation rate of 3500 tons/day may exceed 30 thousand tons/day by the year 2020.The mixed waste dumped at dumping sites is characterized with high organic content and high moisture content (about 80% and 50-70% by weight, respectively). According to …


Approaches To Development Of A User-Friendly Community Based Arsenic/Iron Removal Unit In Bangladesh, Khondoker Mahabub Hassan, Farooque Ahmed, Faisal Hai, Saleh Faraj Magram Aug 2012

Approaches To Development Of A User-Friendly Community Based Arsenic/Iron Removal Unit In Bangladesh, Khondoker Mahabub Hassan, Farooque Ahmed, Faisal Hai, Saleh Faraj Magram

Faisal I Hai

The present stydy focuses on the strategies to modify the design of a community based Arsenic - Iron Removal Unit (AIRU) based on the field performance of the AIRU and the feedback from the users. The ultimate aim was to offer a user-friendly and sustainable system. Appropriate modifications in the design of the developed unit reduced the propensities of water head-loss and media clogging, thereby yielding sustained flow rate. Introduction of a simple cleaning procerdure (98% flow-recovery with three successive backwashing sequences) successfully reduced the frequency of requirement of labor-intensive replacement of the whole filter media. Raw water with arsenic …


Chemically Activated Reactions On The C7h5 Energy Surface: Propargyl + Diacetylene, I-C5h3 + Acetylene, And N-C5h3 + Acetylene, Gabriel Da Silva, Adam J. Trevitt Feb 2012

Chemically Activated Reactions On The C7h5 Energy Surface: Propargyl + Diacetylene, I-C5h3 + Acetylene, And N-C5h3 + Acetylene, Gabriel Da Silva, Adam J. Trevitt

Adam Trevitt

This study uses computational chemistry and statistical reaction rate theory to investigate the chemically activated reaction of diacetylene (butadiyne, C4H2) with the propargyl radical (C •H2CCH) and the reaction of acetylene (C 2H2) with the i-C5H3 (CH 2CCCC•H) and n-C5H3 (CHCC •HCCH) radicals. A detailed G3SX-level C7H 5 energy surface demonstrates that the C3H3 + C4H2 and C5H3 + C2H 2 addition reactions proceed with moderate barriers, on the order of 10 to 15 kcal mol-1, and form activated open-chain C 7H5 species that can isomerize to the fulvenallenyl radical with the highest barrier still significantly below the entrance channel …


Products Of The Benzene + O(3p) Reaction, Craig A. Taatjes, David L. Osborn, Talitha M. Selby, Giovanni Meloni, Adam J. Trevitt, Evgeny Epifanovsky, Anna I. Krylov, Baptiste Sirjean, Enoch Dames, Hai Wang Feb 2012

Products Of The Benzene + O(3p) Reaction, Craig A. Taatjes, David L. Osborn, Talitha M. Selby, Giovanni Meloni, Adam J. Trevitt, Evgeny Epifanovsky, Anna I. Krylov, Baptiste Sirjean, Enoch Dames, Hai Wang

Adam Trevitt

No abstract provided.


Reaction Of The C2h Radical With 1-Butyne (C4h6): Low Temperature Kinetics And Isomer-Specific Product Detection, Satchin Soorkia, Adam J. Trevitt, Talitha M. Selby, David L. Osborn, Craig A. Taatjes, Kevin R. Wilson, Stephen R. Leone Feb 2012

Reaction Of The C2h Radical With 1-Butyne (C4h6): Low Temperature Kinetics And Isomer-Specific Product Detection, Satchin Soorkia, Adam J. Trevitt, Talitha M. Selby, David L. Osborn, Craig A. Taatjes, Kevin R. Wilson, Stephen R. Leone

Adam Trevitt

No abstract provided.


Reactions Of The Cn Radical With Benzene And Toluene: Product Detection And Low-Temperature Kinetics, Adam J. Trevitt, Fabien Goulay, Craig A. Taatjes, David L. Osborn, Stephen R. Leone Feb 2012

Reactions Of The Cn Radical With Benzene And Toluene: Product Detection And Low-Temperature Kinetics, Adam J. Trevitt, Fabien Goulay, Craig A. Taatjes, David L. Osborn, Stephen R. Leone

Adam Trevitt

Low-temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165, and 295 K is found to be relatively constant over this temperature range, (3.9−4.9) × 10−10 cm3 molecule−1 s−1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a rate coefficient of 1.3 × 10−10 cm3 molecule−1 s−1 at 105 …


Reactions Of Simple And Peptidic Alpha-Carboxylate Radical Anions With Dioxygen In The Gas Phase, Tony Ly, Benjamin B. Kirk, Pramesh I. Hettiarachchi, Berwyck L. Poad, Adam J. Trevitt, Gabriel Da Silva, Stephen J. Blanksby Feb 2012

Reactions Of Simple And Peptidic Alpha-Carboxylate Radical Anions With Dioxygen In The Gas Phase, Tony Ly, Benjamin B. Kirk, Pramesh I. Hettiarachchi, Berwyck L. Poad, Adam J. Trevitt, Gabriel Da Silva, Stephen J. Blanksby

Adam Trevitt

α-Carboxylate radical anions are potential reactive intermediates in the free radical oxidation of biological molecules (e.g., fatty acids, peptides and proteins). We have synthesised well-defined α-carboxylate radical anions in the gas phase by UV laser photolysis of halogenated precursors in an ion-trap mass spectrometer. Reactions of isolated acetate (CH2CO 2-) and 1-carboxylatobutyl (CH3CH 2CH2CHCO2-) radical anions with dioxygen yield carbonate (CO3-) radical anions and this chemistry is shown to be a hallmark of oxidation in simple and alkyl-substituted cross-conjugated species. Previous solution phase studies have shown that Cα-radicals in peptides, formed from free radical damage, combine with dioxygen to form …


Climate Change In The Dead Heart Of Australia, Joshua Larsen, Gerald C. Nanson, Timothy J. Cohen, Brian G. Jones, John D. Jansen, Jan-Hendrik May Jan 2012

Climate Change In The Dead Heart Of Australia, Joshua Larsen, Gerald C. Nanson, Timothy J. Cohen, Brian G. Jones, John D. Jansen, Jan-Hendrik May

Timothy Cohen

Despite the absence of large-scale glaciation, the Australian continent has experienced substantial environmental change throughout the Quaternary period. This is especially pronounced in central Australia, where one seventh of the continent is drained internally to the depocentre, and lowest point in Australia, Lake Eyre (Figure 1). Research has shown that at one time, large sandy braided and meandering rivers carried water through dunefields to a large freshwater lake system. Today, the rivers are hostage to the dunefield, and floodwaters might only reach Lake Eyre once every ten years or so. In order to understand the development of this arid desert …


Continental Aridification And The Vanishing Of Australia's Megalakes, Timothy J. Cohen, Gerald C. Nanson, John D. Jansen, B. G. Jones, Zenobia Jacobs, P Treble, David M. Price, Jan-Hendrik May, A Smith, Linda K. Ayliffe, John C. Hellstrom Jan 2012

Continental Aridification And The Vanishing Of Australia's Megalakes, Timothy J. Cohen, Gerald C. Nanson, John D. Jansen, B. G. Jones, Zenobia Jacobs, P Treble, David M. Price, Jan-Hendrik May, A Smith, Linda K. Ayliffe, John C. Hellstrom

Timothy Cohen

The nature of the Australian climate at about the time of rapid megafaunal extinctions and humans arriving in Australia is poorly understood and is an important element in the contentious debate as to whether humans or climate caused the extinctions. Here we present a new paleoshoreline chronology that extends over the past 100 k.y. for Lake Mega-Frome, the coalescence of Lakes Frome, Blanche, Callabonna and Gregory, in the southern latitudes of central Australia. We show that Lake Mega-Frome was connected for the last time to adjacent Lake Eyre at 50-47 ka, forming the largest remaining interconnected system of paleolakes on …


Late Quaternary Aeolian And Fluvial Interactions On The Cooper Creek Fan And The Association Between Linear And Source-Bordering Dunes, Strzelecki Desert, Australia, Timothy J. Cohen, Gerald C. Nanson, Joshua R. Larsen, B. G. Jones, David M. Price, Maria Coleman, Tim Pietsch Jan 2012

Late Quaternary Aeolian And Fluvial Interactions On The Cooper Creek Fan And The Association Between Linear And Source-Bordering Dunes, Strzelecki Desert, Australia, Timothy J. Cohen, Gerald C. Nanson, Joshua R. Larsen, B. G. Jones, David M. Price, Maria Coleman, Tim Pietsch

Timothy Cohen

The Innamincka Dome and associated low-gradient fan in the Strzelecki Desert is the product of Cenozoic crustal warping that has aided formation of an extensive array of palaeochannels, source-bordering transverse dunes and superimposed linear dunes. These dunes have impeded the course of Cooper Creek and provided a repository of evidence for Quaternary climate change as well as the interactive processes between transverse and linear dune formation. At Turra, Gidgealpa and sites nearby are extensive fluvial and aeolian sand bodies that date from marine isotope stages (MIS) 8-3 and the Last Glacial Maximum (LGM) and are now surrounded or buried by …