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The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern

Other resources

This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …


Interaction Between Supersonic Disintegrating Liquid Jets And Their Shock Waves, K.-S. Im, S.-K. Cheong, Xin Liu, J. Wang, M.-C. Lai, M. W. Tate, A. Ercan, M. J. Renzi, D. R. Schuette, S. M. Gruner Feb 2009

Interaction Between Supersonic Disintegrating Liquid Jets And Their Shock Waves, K.-S. Im, S.-K. Cheong, Xin Liu, J. Wang, M.-C. Lai, M. W. Tate, A. Ercan, M. J. Renzi, D. R. Schuette, S. M. Gruner

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The use of additional spectral filtration for dual-energy (DE) imaging using a dual-source CT (DSCT) system was investigated and its effect on the material-specific DEratio was evaluated for several clinically relevant materials. The x-ray spectra, data acquisition, and reconstruction processes for a DSCT system (Siemens Definition) were simulated using information provided by the system manufacturer, resulting in virtual DE images. The factory-installed filtration for the 80 kV spectrum was left unchanged to avoid any further reductions in tube output, and only the filtration for the high-energy spectrum was modified. Only practical single-element filter materials within the atomic number range of …


System And Method For Quantitative Imaging Of Chemical Composition To Decompose More Than Two Materials, Xin Liu, L. Yu, C. H. Mccollough Jan 2009

System And Method For Quantitative Imaging Of Chemical Composition To Decompose More Than Two Materials, Xin Liu, L. Yu, C. H. Mccollough

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A system and method for decomposing more than two materials in an imaging object includes performing a CT imaging acquisition of a portion of an imaging object using at least two energy levels to acquire imaging data associated with each of the at least two energy levels. A total mass attenuation of the imaging data is expressed as a weighted sum of constituent element mass attenuation coefficients and an effective atomic number and density of the constituent elements in the portion of the imaging object is determined by one of a number of methods. Accordingly, concentration of the constituent elements …


Hydrothermal Preparation Of Gd+3 -Doped Titanate Nanotubes: Magnetic Properties And Photovoltaic Performance, Hoda S. Hafez, M Saif, James T. Mcleskey Jr., M.S.A. Abdel-Mottaleb, I S. Yahia, T Story, W Knoff Jan 2009

Hydrothermal Preparation Of Gd+3 -Doped Titanate Nanotubes: Magnetic Properties And Photovoltaic Performance, Hoda S. Hafez, M Saif, James T. Mcleskey Jr., M.S.A. Abdel-Mottaleb, I S. Yahia, T Story, W Knoff

Mechanical and Nuclear Engineering Publications

Pure and Gd+3 -doped titanate nanotubes (TNTs) materials were synthesized by a hydrothermal method. Their morphology, optical properties, thermal stability, and magnetic properties were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), UV-Vis spectroscopy, thermal analysis, and magnetic measurements. It was found that doping renders Gd+3-TNT visible light active and results in smaller crystallite size and larger surface area as well as higher thermal stability compared to pure titanate nanotubes. The estimated magnetic moments point to presence of weak antiferromagnetic interaction. Application of the prepared Gd+3-TNT for modifying conventional photoanodes in polymer solar cells was attempted. Preliminary results show …


Nanostructured Solid-State Hybrid Photovoltaic Cells Fabricated By Electrostatic Layer-By-Layer Deposition, Rolf Kniprath, James T. Mcleskey Jr., Jürgen P. Rabe, Stefan Kirstein Jan 2009

Nanostructured Solid-State Hybrid Photovoltaic Cells Fabricated By Electrostatic Layer-By-Layer Deposition, Rolf Kniprath, James T. Mcleskey Jr., Jürgen P. Rabe, Stefan Kirstein

Mechanical and Nuclear Engineering Publications

We report on the fabrication of hybrid organic/inorganic photovoltaic cells utilizing layer-by-layer deposition of water-soluble polyions and nanocrystals. A bulk heterojunction structure was created consisting of alternating layers of the p-conductive polythiophene derivative poly[2-(3-thienyl)-ethoxy-4-butylsulfonate] and n-conductive TiO2nanoparticles. We fabricated working devices with the heterostructure sandwiched between suitable charge carrier blocking layers and conducting oxide and metal electrodes, respectively. We analyzed the influence of the thickness and nanostructure of the active layer on the cell performance and characterized the devices in terms of static and transient current response with respect to illumination and voltage conditions. We observed reproducible and stable photovoltaic …


Energy Security: An Australian Nuclear Power Industry, Geoff I. Swan Jan 2009

Energy Security: An Australian Nuclear Power Industry, Geoff I. Swan

Australian Security and Intelligence Conference

Climate change and energy security are driving a worldwide renaissance in nuclear power. An Australian nuclear power industry has also been seriously investigated by the Australian government and its agencies. This paper provides a broad overview of the nuclear fuel cycle and the nuclear power industry. It identifies aspects that are sensitive to nuclear terrorism and nuclear weapons proliferation to help security professionals identify threats and prepare for a possible Australian nuclear power industry.


A Realistic Modeling Of Fluid Infiltration In Thin Fibrous Sheets, Sudhakar Jaganathan, Hooman Vahedi Tafreshi, Behnam Pourdeyhimi Jan 2009

A Realistic Modeling Of Fluid Infiltration In Thin Fibrous Sheets, Sudhakar Jaganathan, Hooman Vahedi Tafreshi, Behnam Pourdeyhimi

Mechanical and Nuclear Engineering Publications

In this paper, a modeling study is presented to simulate the fluid infiltration in fibrous media. The Richards’ equation of two-phase flow in porous media is used here to model the fluid absorption in unsaturated/partially saturated fibrous thin sheets. The required consecutive equations, relative permeability, and capillary pressure as functions of medium’s saturation are obtained via fiber-level modeling and a long-column experiment, respectively. Our relative permeability calculations are based on solving the Stokes flow equations in partially saturated three-dimensional domains obtained by imaging the sheets’ microstructures. The Richards’ equation, together with the above consecutive correlations, is solved for fibrous media …


System And Method For Quantitative Imaging Of Chemical Composition To Decompose Multiple Materials, Xin Liu, L. Yu, C. H. Mccollough Jan 2009

System And Method For Quantitative Imaging Of Chemical Composition To Decompose Multiple Materials, Xin Liu, L. Yu, C. H. Mccollough

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The present invention provides a material decomposition method capable of determining the distribution of density and constituent material concentration throughout an imaged object. The concentration, in the form of a mass fraction, mass percent, weight fraction, or weight percent, is determined from CT images acquired at different energy levels. The ratio of attenuation coefficients associated with one energy level to attenuation coefficients associated with another energy level is determined and used as an index in a lookup table to determine the concentration of a given material throughout the imaged object.