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You searched for subject:( Flow conceptualisation). Showing records 1 – 3 of 3 total matches.

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University of Pretoria

1. Van Wyk, Yazeed. Transport mechanisms of uranium and thorium in fractured rock aquifers.

Degree: Geology, 2011, University of Pretoria

The Karoo has been receiving considerable attention since the early 1970’s when uranium mining was at its peak, with numerous research studies being instigated to look at all aspects of uranium mining. It has recently been observed that there seems to be resurgence in uranium exploration in and around the town of Beaufort West. A study on the transport mechanisms of uranium and thorium in fractured-rock aquifers, initiated in the hope of understanding the actual processes controlling radionuclide mobilisation, is reported here. Hydrochemical investigations of the various boreholes were sampled for water quality in June, 2009. The hydrochemical description is typical of shallow fresh groundwater, changing composition to a more sulphate hydrochemical facies along the flow path. While the geochemistry of groundwater in the study area seems to have minimal effects on uranium concentrations, the low levels of uranium in boreholes sampled suggest the importance of hydrological and lithological variability on the measured concentrations. Nevertheless, the uranium concentration is within the recommended levels as specified in the US-EPA, WHO and SA water quality guidelines and thus poses no immediate threat to the general public. Analysis of pumping and tracer tests, reveals that the fractured-rock aquifer can be highly transmissive and that transport can take place via multiple flow paths having different hydraulic properties. Tracer diffusing into stagnant water zones within fracture asperities and the rock matrix are seen as an important retardation mechanism, that has implications for remediation should the aquifer be contaminated by radionuclides. In terms of conceptualising flow at a local scale, aperture sizes ranging from (563-828ìm) along with high flow velocities (1.90E-03m/s), points to the importance of bedding-plane fractures as conduits of groundwater flow. The groundwater flow has been influenced by dolerite dykes creating compartments isolated from each other, suggesting a highly complex aquifer system. Based on the conceptual model, it is shown that these structures can create unique, site specific flow conditions. The integration of all available data into the conceptual model provides an effective research tool that can be built upon as a basis for further research. Advisors/Committee Members: Prof K T Witthueser (advisor), Mr M A Dippenaar (advisor), Prof J L Van Rooy (advisor).

Subjects/Keywords: Beaufort west; Hydrogeology; Fractured rock aquifer; Radioactivity; Transport mechanisms; Tracer test; Pumping test; Flow conceptualisation; UCTD

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Van Wyk, Y. (2011). Transport mechanisms of uranium and thorium in fractured rock aquifers. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/25799

Chicago Manual of Style (16th Edition):

Van Wyk, Yazeed. “Transport mechanisms of uranium and thorium in fractured rock aquifers.” 2011. Masters Thesis, University of Pretoria. Accessed October 14, 2019. http://hdl.handle.net/2263/25799.

MLA Handbook (7th Edition):

Van Wyk, Yazeed. “Transport mechanisms of uranium and thorium in fractured rock aquifers.” 2011. Web. 14 Oct 2019.

Vancouver:

Van Wyk Y. Transport mechanisms of uranium and thorium in fractured rock aquifers. [Internet] [Masters thesis]. University of Pretoria; 2011. [cited 2019 Oct 14]. Available from: http://hdl.handle.net/2263/25799.

Council of Science Editors:

Van Wyk Y. Transport mechanisms of uranium and thorium in fractured rock aquifers. [Masters Thesis]. University of Pretoria; 2011. Available from: http://hdl.handle.net/2263/25799


University of Pretoria

2. [No author]. Transport mechanisms of uranium and thorium in fractured rock aquifers .

Degree: 2011, University of Pretoria

The Karoo has been receiving considerable attention since the early 1970’s when uranium mining was at its peak, with numerous research studies being instigated to look at all aspects of uranium mining. It has recently been observed that there seems to be resurgence in uranium exploration in and around the town of Beaufort West. A study on the transport mechanisms of uranium and thorium in fractured-rock aquifers, initiated in the hope of understanding the actual processes controlling radionuclide mobilisation, is reported here. Hydrochemical investigations of the various boreholes were sampled for water quality in June, 2009. The hydrochemical description is typical of shallow fresh groundwater, changing composition to a more sulphate hydrochemical facies along the flow path. While the geochemistry of groundwater in the study area seems to have minimal effects on uranium concentrations, the low levels of uranium in boreholes sampled suggest the importance of hydrological and lithological variability on the measured concentrations. Nevertheless, the uranium concentration is within the recommended levels as specified in the US-EPA, WHO and SA water quality guidelines and thus poses no immediate threat to the general public. Analysis of pumping and tracer tests, reveals that the fractured-rock aquifer can be highly transmissive and that transport can take place via multiple flow paths having different hydraulic properties. Tracer diffusing into stagnant water zones within fracture asperities and the rock matrix are seen as an important retardation mechanism, that has implications for remediation should the aquifer be contaminated by radionuclides. In terms of conceptualising flow at a local scale, aperture sizes ranging from (563-828ìm) along with high flow velocities (1.90E-03m/s), points to the importance of bedding-plane fractures as conduits of groundwater flow. The groundwater flow has been influenced by dolerite dykes creating compartments isolated from each other, suggesting a highly complex aquifer system. Based on the conceptual model, it is shown that these structures can create unique, site specific flow conditions. The integration of all available data into the conceptual model provides an effective research tool that can be built upon as a basis for further research. Advisors/Committee Members: Prof K T Witthueser (advisor), Mr M A Dippenaar (advisor), Prof J L Van Rooy (advisor).

Subjects/Keywords: Beaufort west; Hydrogeology; Fractured rock aquifer; Radioactivity; Transport mechanisms; Tracer test; Pumping test; Flow conceptualisation; UCTD

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

author], [. (2011). Transport mechanisms of uranium and thorium in fractured rock aquifers . (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-06242011-155219/

Chicago Manual of Style (16th Edition):

author], [No. “Transport mechanisms of uranium and thorium in fractured rock aquifers .” 2011. Masters Thesis, University of Pretoria. Accessed October 14, 2019. http://upetd.up.ac.za/thesis/available/etd-06242011-155219/.

MLA Handbook (7th Edition):

author], [No. “Transport mechanisms of uranium and thorium in fractured rock aquifers .” 2011. Web. 14 Oct 2019.

Vancouver:

author] [. Transport mechanisms of uranium and thorium in fractured rock aquifers . [Internet] [Masters thesis]. University of Pretoria; 2011. [cited 2019 Oct 14]. Available from: http://upetd.up.ac.za/thesis/available/etd-06242011-155219/.

Council of Science Editors:

author] [. Transport mechanisms of uranium and thorium in fractured rock aquifers . [Masters Thesis]. University of Pretoria; 2011. Available from: http://upetd.up.ac.za/thesis/available/etd-06242011-155219/


Queensland University of Technology

3. Boyd, Roger Frederick. Modes of thought in secondary school art.

Degree: 1999, Queensland University of Technology

Subjects/Keywords: Art Study and teaching (Secondary); Thought and thinking; art; thinking-skills; cognition; modes-of-thought; micro-skills; creative-thinking; creativity; intuitive thinking; intuition; life-theme; expression; self-expression; metaphorising; symbol; metaphor; visual-thinking; visual; vision; perception; conceptualisation; concept; percept; critical-thinking; reasoning; reflective-thinking; metacognition; aesthetics; multiple-intelligences; dimensions-of-learning; secondary-education; secondary-school; secondary; William-Robinson; Robinson; Lyndall-Milani; Milani; Shane-Thompson; Thompson; John-Ivanac; Ivanac; Judy-Watson; Watson; problem-finding; problem-solving; flow; leap; decision-making; synectic-thinking; synectic; investigation; analysis; justification; planning; thesis; masters

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Boyd, R. F. (1999). Modes of thought in secondary school art. (Thesis). Queensland University of Technology. Retrieved from http://eprints.qut.edu.au/36645/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Boyd, Roger Frederick. “Modes of thought in secondary school art.” 1999. Thesis, Queensland University of Technology. Accessed October 14, 2019. http://eprints.qut.edu.au/36645/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Boyd, Roger Frederick. “Modes of thought in secondary school art.” 1999. Web. 14 Oct 2019.

Vancouver:

Boyd RF. Modes of thought in secondary school art. [Internet] [Thesis]. Queensland University of Technology; 1999. [cited 2019 Oct 14]. Available from: http://eprints.qut.edu.au/36645/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Boyd RF. Modes of thought in secondary school art. [Thesis]. Queensland University of Technology; 1999. Available from: http://eprints.qut.edu.au/36645/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.