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Properties Of The B+-H2 And B+-D2 Complexes: A Theoretical And Spectroscopic Study, B L. J Poad, V Dryza, A A. Buchachenko, J Kos, E J. Bieske
Properties Of The B+-H2 And B+-D2 Complexes: A Theoretical And Spectroscopic Study, B L. J Poad, V Dryza, A A. Buchachenko, J Kos, E J. Bieske
Faculty of Science - Papers (Archive)
The rotationally resolved infrared spectrum of the B+-D2 ion-neutral complex is recorded in the D-D stretch vibration region (2805–2875 cm−1) by detecting B+ photofragments. Analysis of the spectrum confirms a T-shaped equilibrium geometry for the B+-D2 complex with a vibrationally averaged intermolecular bond length of 2.247 Å, around 0.02 Å shorter than for the previously characterised B+-H2 complex [V. Dryza, B. L. J. Poad, and E. J. Bieske, J. Am. Chem. Soc. 130, 12986 (2008)10.1021/ja8018302]. The D-D stretch band centre occurs at 2839.76 ± 0.10 cm−1, representing a −153.8 cm−1 shift from the Q1(0) transition of the free D2 molecule. …
Spectroscopic And Computational Study Of Β-Ethynylphenylene Substituted Zinc And Free-Base Porphyrins, John C. Earles, Keith C. Gordon, Adam W. I Stephenson, Ashton C. Partridge, David L. Officer
Spectroscopic And Computational Study Of Β-Ethynylphenylene Substituted Zinc And Free-Base Porphyrins, John C. Earles, Keith C. Gordon, Adam W. I Stephenson, Ashton C. Partridge, David L. Officer
Faculty of Science - Papers (Archive)
A series of tetraphenylporphyrins appended at the β-pyrrolic position with an ethynylphenylene- or ethynylpyridine-substituent have been subjected to spectroscopic and density functional theory (DFT) analyses. The mean absolute deviation between corresponding experimental and DFT-derived vibrational spectra is up to 10.2 cm -1, suggesting that the DFT B3LYP/6-31G(d) method provides an accurate model of the β-substituted porphyrin systems. The configuration interactions that give rise to prominent electronic absorptions have been calculated using time-dependant DFT (TD-DFT) and have been rationalized with reference to the energy and topology of DFT calculated molecular orbitals. As the electron withdrawing capacity of the β-substituent increases the …
Rotationally Resolved Infrared Spectrum Of The Na+-D2 Complex: An Experimental And Theoretical Study, Berwyck L. Poad, V Dryza, J Klos, A A. Buchachenko, E J. Bieske
Rotationally Resolved Infrared Spectrum Of The Na+-D2 Complex: An Experimental And Theoretical Study, Berwyck L. Poad, V Dryza, J Klos, A A. Buchachenko, E J. Bieske
Faculty of Science - Papers (Archive)
The infrared spectrum of mass-selected Na+-D2 complexes is recorded in the D-D stretch vibration region (2915-2972 cm−1) by detecting Na+ photofragments resulting from photo-excitation of the complexes. Analysis of the rotationally resolved spectrum confirms a T-shaped equilibrium geometry for the complex and a vibrationally averaged intermolecular bond length of 2.461 Å. The D-D stretch band centre occurs at 2944.04 cm−1, representing a −49.6 cm−1 shift from the Q1(0) transition of the free D2 molecule. Variational rovibrational energy level calculations are performed for Na+-D2 utilising an ab initio potential energy surface developed previously for investigating the Na+-H2 complex [B. L. J. …
How Well Do Predators Adjust To Climate-Mediated Shifts In Prey Distribution? A Study On Australian Water Pythons, Beata Ujvari, Rick Shine, Thomas Madsen
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 …
The Response Of Melita Plumulosa To Continuous And Pulsed Exposures To Contaminated Sediment: A Study Of Avoidance And Toxicity, D J. Ward, D F. Jolley, Stuart L. Simpson
The Response Of Melita Plumulosa To Continuous And Pulsed Exposures To Contaminated Sediment: A Study Of Avoidance And Toxicity, D J. Ward, D F. Jolley, Stuart L. Simpson
Faculty of Science - Papers (Archive)
The distribution of contaminants is seldom homogeneous in aquatic systems and microniches within benthic sediments can make them particularly heterogeneous. Following exposure to ‘pulsed’ dissolved copper concentrations, toxicity to the epibenthic amphipod, Melita plumulosa, is best described by the time-averaged concentration. In this study we investigated the behavioural response of M. plumulosa, to contaminated marine sediments. Based on the rate at which the organism avoided contamination, we then investigated how toxic effects may occur through pulsed exposures to contaminated sediments. Four field-contaminated marine sediments were collected from the field and characterised as containing potentially toxic concentrations of metals. These sediments …
Photoelectrochemical Cell Study On Closely Arranged Vertical Nanorod Bundles Of Cdse And Zn Doped Cdse Films, D Soundararajan, J K. Yoon, J S. Kwon, Y I. Kim, S H. Kim, J H. Park, Y J. Kim, D -Y Park, B C. Kim, G G. Wallace, J M. Ko
Photoelectrochemical Cell Study On Closely Arranged Vertical Nanorod Bundles Of Cdse And Zn Doped Cdse Films, D Soundararajan, J K. Yoon, J S. Kwon, Y I. Kim, S H. Kim, J H. Park, Y J. Kim, D -Y Park, B C. Kim, G G. Wallace, J M. Ko
Faculty of Science - Papers (Archive)
Closely arranged CdSe and Zn doped CdSe vertical nanorod bundles were grown directly on FTO coated glass by using electrodeposition method. Structural analysis by XRD showed the hexagonal phase without any precipitates related to Zn. FE-SEM image showed end capped vertically aligned nanorods arranged closely. From the UV-vis transmittance spectra, band gap energy was found to vary between 1.94 and 1.98 eV due to the incorporation of Zn. Solar cell parameters were obtained by assembling photoelectrochemical cells using CdSe and CdSe:Zn photoanodes, Pt cathode and polysulfide (1M Na2S + 1M S + 1M NaOH) electrolyte. The efficiency was found to …
A Multi-Scale Geospatial Study Of Wetlands Distribution And Agricultural Zones, And The Case Of India, N Nagabhatla, Rohan Wickramasuriya, N Prasad, Max Finlayson
A Multi-Scale Geospatial Study Of Wetlands Distribution And Agricultural Zones, And The Case Of India, N Nagabhatla, Rohan Wickramasuriya, N Prasad, Max Finlayson
Faculty of Science - Papers (Archive)
This paper highlights the global and the regional scale representation of wetlands ecosystems using geospatial tools and multiple data sets. At global scale, the Ramsar database is investigated for representation of the wetlands sites of international importance against the "global agricultural zones" derived from the thematic aggregation of Global Irrigated Area Map databases. The analysis of "Ramsar sites" under cultivation reflects the present trend in wetlands use for agriculture. The scenario is also compared with the historical pattern derived from Vavilov's food zones of 1926. Observed is an aggregate increase in cropped wetlands area from 25% (1926) to 43% (2006). …
A Combined Experimental And Theoretical Study Of Ion Solvation In Liquid N-Methylacetamide, Haibo Yu, Christopher L. Mazzanti, Troy W. Whitfield, Roger E. Koeppe Ii, Olaf S. Andersen, Benoit Roux
A Combined Experimental And Theoretical Study Of Ion Solvation In Liquid N-Methylacetamide, Haibo Yu, Christopher L. Mazzanti, Troy W. Whitfield, Roger E. Koeppe Ii, Olaf S. Andersen, Benoit Roux
Faculty of Science - Papers (Archive)
Most current biomolecular simulations are based on potential energy functions that treat the electrostatic energy as a sum of pairwise Coulombic interactions between effective fixed atomic charges. This approximation, in which many-body induced polarization effects are included in an average way, is expected to be satisfactory for a wide range of systems, but less accurate for processes involving the transfer and partition of ions among heterogeneous environments. The limitations of these potential energy functions are perhaps most obvious in studies of ion permeation through membrane channels. In many cases, the pore is so narrow that the permeating ion must shed …
The Length Distributions Of Non-Coding And Coding Sequences In Relation To Gene Expression: A Study On Arabidopsis Thaliana, R Caldwell, J Kongcharoen, Y Lin, R Zhang
The Length Distributions Of Non-Coding And Coding Sequences In Relation To Gene Expression: A Study On Arabidopsis Thaliana, R Caldwell, J Kongcharoen, Y Lin, R Zhang
Faculty of Science - Papers (Archive)
No abstract provided.
Spectroscopic Study Of The Benchmark Mn+-H2 Complex, Viktoras Dryza, Berwyck L. J Poad, Evan J. Bieske
Spectroscopic Study Of The Benchmark Mn+-H2 Complex, Viktoras Dryza, Berwyck L. J Poad, Evan J. Bieske
Faculty of Science - Papers (Archive)
We have recorded the rotationally resolved infrared spectrum of the weakly bound Mn+-H2 complex in the H-H stretch region (4022-4078 cm(-1)) by monitoring Mn+ photodissociation products. The band center of Mn+-H2, the H-H stretch transition, is shifted by -111.8 cm(-1) from the transition of the free H2 molecule. The spectroscopic data suggest that the Mn+-H2 complex consists of a slightly perturbed H2 molecule attached to the Mn+ ion in a T-shaped configuration with a vibrationally averaged intermolecular separation of 2.73 A. Together with the measured Mn+...H2 binding energy of 7.9 kJ/mol (Weis, P.; et al. J. Phys. Chem. A 1997, …
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
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 …
On The Utilization Of Energy Minimization To The Study Of Ion Selectivity, Haibo Yu, Benoit Roux
On The Utilization Of Energy Minimization To The Study Of Ion Selectivity, Haibo Yu, Benoit Roux
Faculty of Science - Papers (Archive)
The major pitfalls in studying ion selectivity in binding site models using energy minimization based methods are examined and discussed. It is shown that the properties derived from energy minimization are strongly configuration-dependent and that the results should be interpreted with caution. It is concluded that computational studies of ion selectivity must include thermal fluctuations and entropic effects.
Nmr Study Of Complexes Between Low Molecular Mass Inhibitors And The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, Hiromasa Yagi, S P. Lim, D Wen, D Ekonomiuk, D Huang, T Keller, S Sonntag, A Caflisch, S G. Vasudevan, G Otting
Nmr Study Of Complexes Between Low Molecular Mass Inhibitors And The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, Hiromasa Yagi, S P. Lim, D Wen, D Ekonomiuk, D Huang, T Keller, S Sonntag, A Caflisch, S G. Vasudevan, G Otting
Faculty of Science - Papers (Archive)
The two-component NS2B-NS3 protease of West Nile virus is essential for its replication and presents an attractive target for drug development. Here, we describe protocols for the high-yield expression of stable isotope-labelled samples in vivo and in vitro. We also describe the use of NMR spectroscopy to determine the binding mode of new low molecular mass inhibitors of the West Nile virus NS2B-NS3 protease which were discovered using high-throughput in vitro screening. Binding to the substrate-binding sites S1 and S3 is confirmed by intermolecular NOEs and comparison with the binding mode of a previously identified low molecular mass inhibitor. Our …
Attachment Of Molecular Hydrogen To An Isolated Boron Cation: An Infrared And Ab Initio Study, Viktoras Dryza, Berwyck L. J Poad, Evan J. Bieske
Attachment Of Molecular Hydrogen To An Isolated Boron Cation: An Infrared And Ab Initio Study, Viktoras Dryza, Berwyck L. J Poad, Evan J. Bieske
Faculty of Science - Papers (Archive)
Structural properties of the B+−H2 electrostatic complex are investigated through its rotationally resolved infrared spectrum in the H−H stretch region (3905−3975 cm−1). The spectrum, which was obtained by monitoring B+ photofragments while the IR wavelength was scanned, is consistent with the complex having a T-shaped structure and a vibrationally averaged intermolecular separation of 2.26 Å, which decreases by 0.04 Å when the H2 subunit is vibrationally excited. The H−H stretch transition of B+−H2 is red-shifted by 220.6 ± 1.5 cm−1 from that of the free H2 molecule, much …
Appraisal Of A One-Dimensional Model, Field Data And Dimensionless Parameters In A Study Of Estuarine Circulation, Errol J. Mclean, J. B. Hinwood
Appraisal Of A One-Dimensional Model, Field Data And Dimensionless Parameters In A Study Of Estuarine Circulation, Errol J. Mclean, J. B. Hinwood
Faculty of Science - Papers (Archive)
Parallel research programs encompassing the hydrodynamics and geochemistry have been undertaken in Oatley Bay, a small urban estuary that is a lower tributary to the Georges River in Southern Sydney Using field data and a simple numerical model, the regimes of flow effecting circulation in Oatley Bay have been determined. The efficiency of flushing and the subsequent fate of conservative pollutants are discussed. The field data comprised bathymetry, tides, drogue tracking and dye tests, the latter enabling the calibration of the model under different environmental conditions. With this model we have performed numerous runs and have characterised temporal and spatial …
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
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 …
Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts
Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts
Faculty of Science - Papers (Archive)
Estuaries worldwide are under increasing threat from human impacts. Because much of their fauna remains unstudied and in many cases undescribed, these systems present real challenges for effective management. In eastern Australia the study of estuarine fauna is often further complicated by its patchy distributions. This is particularly the case for assemblages of sessile invertebrates in coastal saline lakes. This study quantified distributions of sponges and ascidians at a hierarchy of spatial scales in the seagrass meadows of 2 coastal saline lakes in New South Wales, Australia. Nine species of sponge, many of which were undescribed, and 3 species of …
Afm In Liquid: A High Sensitivity Study On Biological Membranes, Michael J. Higgins, Takeshi Fukuma, Suzi P. Jarvis
Afm In Liquid: A High Sensitivity Study On Biological Membranes, Michael J. Higgins, Takeshi Fukuma, Suzi P. Jarvis
Faculty of Science - Papers (Archive)
Frequency Modulation AFM (FM-AFM) is commonly operated in ultra-high vacuum, though its inception in liquids for biological samples is relatively new. Here, we highlight the ability of FM-AFM to perform molecular resolution imaging of biomembrane surfaces and to detect individual layers of structured water at similar membrane interfaces. These studies highlight the potential of FM-AFM for studying model membranes and lipid raft systems on the molecular scale.
A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali
A Study On Solid Waste Management System Of Dhaka City Corporation: Effect Of Composting And Landfill Location, Faisal Ibney Hai, M. Ashraf Ali
Faculty of Science - Papers (Archive)
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 …
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
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 …