2010 Summer Research Projects

The 2010 Research Project descriptions are here! Take a look…

 

 

 

Project Title  Description
1. Supercritical Water Reactor Physics Parameter Scoping Project The Generation-IV International Forum (GIF) is a worldwide initiative to research and develop cleaner, safer, and more efficient nuclear technologies. Generation-IV work in Canada is focused on developing the Supercritical Water Reactor (SCWR), a revolutionary design that uses advanced cooling and fuel designs to produce electricity far more efficiently than nuclear reactors operating today. In this project, students will learn about nuclear physics, nuclear reactors, nuclear fuels and fuel cycles, and reactor physics as they work with the Radiation and Reactor Physics branch to explore and develop new designs for the next generation of nuclear reactors.   
2. Preparation and Characterization of Zirconium Alloy Thin Films for Studies of Corrosion Behaviour in Iodine Solutions Iodine, a fission product in nuclear power reactors, can increase the rate of corrosion of the zirconium alloy fuel sheath, as well as its susceptibility to stress corrosion cracking (SCC). This can affect the inreactor life of high burnup fuel. We will insvestigate the effects of alloy and electrolyte composition on the corrosion behaviour of zirconium alloys. The project invloves two phases, which the student will have sole responsibility for:1. Preparation and X-ray characterization of zirconium and zirconium alloy thin films. The student will prepare thin films on Si substrate wafers using a multi-target sputter deposition system. X-ray reflectometry will be used to verify the structure (thickness, density, composition) of the films produced.2. Time Permitting: investigation of the effects of alloy and electrolyte composition on corrosion behaviour. Potentiometric methods will be employed to study the corrosion behaviour of the films in iodine methanol solutions with a range of iodine ion concentrations. X-ray reflectometry will be used ex-situ to investigate corrosion by-products.

DRSA students will get hands-on experience with sputter-deposition, X-ray reflectometry, and potentiometric methods. Ultimately, we plan to use neutron relfectometry (NR) to study in-situ the onset and progression of corrosion. This technique cn provide quantitative data on the nature and thickness of corrosion films. This project will lay the foundation for futurre neutron diffraction work.
3. Grain Thickness using TEM The Deep River Science Academy students will be studying the microstructures of pressure tube materials with a Transmission Electron Microscope (TEM).  They will learn to prepare electron-transparent foils and operate the TEM to examine them.  Images of the microstructure will be taken, analyzed and compared to those previously taken with a Scanning Electron Microscope (SEM).  Grain thicknesses will be measured and correlated to pressure tube properties using descriptive statistical methods.  Using these techniques, further knowledge of pressure tube material will be gained and help minimize pressure tube elongation.  
 4. Determination of the significance of ATP bioluminescence assay for deep groundwater and soil microbial population characterization ATP bioluminescence assays are increasingly being used in microbial population studies. The purpose of this project is to determine it ATP values correlate with the total number of microbes, the total number of viable microbes or the total number of cultivable microbes. Testing will be conducted using laboratory cultures and environmental samples to determine the significance of the assay with respect to these parameters. Laboratory practices will include fluorescent staining and microscopic counts; intracellular and/or extracellular ATP analysis; and the characterization of microbial communities using fluorescent in-situ hybridization (FISH).  
 5. Hydrogen absorption and desorption properties of thin MgAl alloy films NRC’s Canadian Neutron Beam Centre focuses its research activities in the area of hydrogen storage materials on improving the absorption and desorption properties of Mg-based alloys. Thin films are used as model systems to obtain a better understanding of the fundamental mechanisms involved in absorbing/desorbing hydrogen into/from metals, whereas the powder form would be used as a storage medium in commercial applications. The DRSA project covers both aspects.The student will study thin Mg-based alloy films with a thickness of typically 50 nm and investigate the hydrogen content and structural change of the film structures during absorptions and desorption (i.e. film expansion, film roughness, crystal structure) with x-ray reflectometry (XRR) and x-ray diffraction (XRD). The comparison of the film structure (determined with XRR) with the crystal structure (determined by XRD) measured in-situ will give us more insight into the desorption properties of Mg-based alloys. During the project the student will learn how to use a state-of-the-art x-ray instrument, understand how and why to use diffraction, and use existing software to analyze the XRR curves, and Bragg peaks in the XRD scans. For powder samples, the student will calibrate a so-called pcT-apparatus that will be capable of determinging the hydrogen content © of a powder sample at a constant temperature (T) by measuring the pressure (p). 
 6. Measuring mechanical properties with increased hydrogen levels Increased hydrogen levels in zirconium alloy pressure tubes in CANDU reactors can result in degradation of mechanical properties.  In an effort to measure mechanical properties with increased hydrogen levels, hydrogen is added to pressure tube material.  The used method is with an electrolysis process to create a hydride layer on the surface followed by an annealing process to diffuse the hydrogen into the zirconium for a homogenous material. This research project would look at parameters affecting the quality and thickness of the hydride layer.
7. Single and Two-Phase Pressure Drops over Longer Fuel Bundles The operation of a CANDU reactor involves producing great quantities of heat, which must be controlled and cooled. Cooling is induced by pumping coolant around and through the bundles where the fuel is stored, allowing heat transfer to occur from the fuel bundles to the fluid. During this process, major and minor head losses occur due to factors such as skin friction and form drag, resulting in pressure drops as the fluid flows down the bundle. Thus, a balance must be found between increasing the fluid flow – which requires the use of a bigger pump and greater operating costs – and using a reduced flow, which decreases the output of the reactor.Under Research and Development, CANDU bundles with twice the existing length and two additional appendage planes will be investigated. This project will therefore focus on the effects of the additional length and appendage planes on the pressure drop down a string of bundles.Students working on this project will used pressure taps and differential pressure cells in order to determine the extent of pressure drop down the bundle and across specific appendages such as the junctions and spacers. The differences in pressure will also be measured when the flow rates and the number of phases are varied. The results from this study will then be compared with results obtained using shorter bundles.
8. Ion exchange CANDU reactors use lithium hydroxide to regulate the pH of the heat transport system water. An ion exchange resin is used to regulate the amount of lithium present. However, over time the lithium concentration in the coolant increases, leading to the need to remove the excess lithium on a different ion exchange column. A previous DRSA project has investigate the hypothesis that this is due to trace concentrations of iron present in the coolant from corrosion of system piping, displacing lithium ion from the resin. Students will attempt to show this iron impurity is the cause of the rising lithium concentrations, and test different resin arrangements to determine which is most resistant to lithium release as the result of the presence of iron. The goal is to optimize the ion exchange resin mixture to minimize the usage of the separate lithium-removal column.
9. Hydrogeology and Biogeochemistry of Glaciofluvial Aquifers Sediment deposits left behind by glaciers have a strong influence on the water quality of shallow aquifers.  To assess the impact of the rocks and minerals present, we intend to combine practices from the fields of geology, chemistry, hydrology, and biology.  By creating a series of boreholes in the glacial sediments, we can collect soil and water samples.  The soil will be analyzed for mineralogical composition, and any bacteria present will be identified by DNA sequencing.  Measurements of pH, reduction-oxidation potential, and electrical conductivity will be done in the field for water samples, and a detailed chemical study will be done in an in-camp lab. 

Piezometers installed in the boreholes will tell us the elevation of the water table.  The final product will be a map expressing an understanding of the local relationships between groundwater flow directions, soil mineralogy, and aquifer geochemistry and biochemistry.

 

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