subject:(Conductivity)

Texas A&M University

1. Fernandes, Preston X. Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress.

Degree: 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6977

► Ultra-deepwater reservoirs are important non-conventional reservoirs that hold the potential to produce billions of barrels of hydrocarbons but present major challenges. Hydraulic fracturing or frac-packing… (more)

▼ Ultra-deepwater reservoirs are important non-conventional reservoirs that hold the potential to produce billions of barrels of hydrocarbons but present major challenges. Hydraulic fracturing or frac-packing high permeability reservoirs is different from the conventional hydraulic fracturing technology used in low permeability formations. While the main purpose of the conventional technique is to create a long, highly conductive path, frac-packing on the other hand is used predominantly to get past near wellbore formation damage, control sand production and reduce near wellbore pressure drop. Ultra-deepwater reservoirs are usually high temperature and high pressure with high permeabilities. Frac-packing these types of wells requires short fractures packed with high proppant concentrations. Understanding the behavior of the fracture fluid and proppant is critical to pump such a job successfully and to ensure long term productivity from the fracture. A series of laboratory experiments have been conducted to research the different problems resulting from high temperature and pressure which negatively affect conductivity. Unlike conventional long-term conductivity measurements, we placed the proppant into the fracture and pumped fracture fluid through it and then measured conductivity by pumping oil to represent true reservoir conditions. Proppant performance and fracture fluids clean-up during production were examined. High strength proppant is ideal for deep fracture stimulations and in this study different proppant loadings at different stresses were tested to measure the impact of crushing and embedment on conductivity. The preliminary test results indicated that oil at reservoir conditions does improve clean-up of fracture fluid left back in the proppant pack. Increasing the proppant concentration in the fracture showed higher conductivity values even at high closure stress. The increase in effective closure stress with high temperature yielded significant loss in conductivity values as compared to those obtained from industry tests. Advisors/Committee Members: Zhu, Ding (advisor), Hill, Alfred D. (committee member), Sun, Yuefung (committee member).

Subjects/Keywords: Conductivity

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APA (6^th Edition):

Fernandes, P. X. (2010). Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6977

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

Chicago Manual of Style (16^th Edition):

Fernandes, Preston X. “Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress.” 2010. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6977.

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

MLA Handbook (7^th Edition):

Fernandes, Preston X. “Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress.” 2010. Web. 26 Feb 2020.

Vancouver:

Fernandes PX. Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6977.

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

Council of Science Editors:

Fernandes PX. Measuring Frac-pack Conductivity at Reservoir Temperature and High Closure Stress. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6977

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

University of Zambia

2. Hatwaambo, Sylvester A. Geometrical effects in the conductivity of low dimensional structures .

Degree: 2012, University of Zambia

URL: http://hdl.handle.net/123456789/1545

► This work is an experimental study on percolation and electrical conductivity in two-dimensions with an aim of confirming some of the theoretical predictions, and measuring… (more)

Subjects/Keywords: Electric Conductivity; Electrolytes – Conductivity

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APA (6^th Edition):

Hatwaambo, S. A. (2012). Geometrical effects in the conductivity of low dimensional structures . (Thesis). University of Zambia. Retrieved from http://hdl.handle.net/123456789/1545

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

Chicago Manual of Style (16^th Edition):

Hatwaambo, Sylvester A. “Geometrical effects in the conductivity of low dimensional structures .” 2012. Thesis, University of Zambia. Accessed February 26, 2020. http://hdl.handle.net/123456789/1545.

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

MLA Handbook (7^th Edition):

Hatwaambo, Sylvester A. “Geometrical effects in the conductivity of low dimensional structures .” 2012. Web. 26 Feb 2020.

Vancouver:

Hatwaambo SA. Geometrical effects in the conductivity of low dimensional structures . [Internet] [Thesis]. University of Zambia; 2012. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/123456789/1545.

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

Council of Science Editors:

Hatwaambo SA. Geometrical effects in the conductivity of low dimensional structures . [Thesis]. University of Zambia; 2012. Available from: http://hdl.handle.net/123456789/1545

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

University of Hawaii – Manoa

3. Ripple, James K. A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu.

Degree: 2016, University of Hawaii – Manoa

URL: http://hdl.handle.net/10125/101434

►

M.S. University of Hawaii at Manoa 2011.

The purpose of this study is to measure with research laboratory accuracy, the hydraulic conductivity of soils sampled… (more)

Subjects/Keywords: hydraulic conductivity

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APA (6^th Edition):

Ripple, J. K. (2016). A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu. (Thesis). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/101434

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

Chicago Manual of Style (16^th Edition):

Ripple, James K. “A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu.” 2016. Thesis, University of Hawaii – Manoa. Accessed February 26, 2020. http://hdl.handle.net/10125/101434.

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

MLA Handbook (7^th Edition):

Ripple, James K. “A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu.” 2016. Web. 26 Feb 2020.

Vancouver:

Ripple JK. A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu. [Internet] [Thesis]. University of Hawaii – Manoa; 2016. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/10125/101434.

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

Council of Science Editors:

Ripple JK. A study of the effects of confinement, soil parameters, and testing methods on the hydraulic conductivity of some finegrained soils on Oahu. [Thesis]. University of Hawaii – Manoa; 2016. Available from: http://hdl.handle.net/10125/101434

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

Texas A&M University

4. Kainer, Cody. Predicting Hydraulic Fracture Conductivity In Shale Plays.

Degree: MS, Petroleum Engineering, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/165842

► The purpose of hydraulic fracturing in low permeability shales is to maximize surface contact area with the reservoir and create conductive flow paths for the… (more)

▼ The purpose of hydraulic fracturing in low permeability shales is to maximize surface contact area with the reservoir and create conductive flow paths for the hydrocarbons to be economically produced through. Fracture conductivity is defined as the product of fracture permeability (kf) and the width of the fracture aperture (wf). This parameter is vital as it limits the capacity of the flow path between the stimulated reservoir rock and the wellbore, for a given drawdown pressure. The resulting fracture conductivity is dependent on a plethora of rock and proppant properties. Realistic prediction of conductivity and further understanding of its relationship with rock properties would prove incredibly valuable, especially in new and developing shale plays where there is a steep initial learning curve in economic production. In this study, multiple linear regression is applied to a large database of shale conductivity experiments and a robust correlation for predicting conductivity is presented. In addition, the properties of Young?s modulus, Poisson?s ratio, compressive strength, and Brinell hardness are isolated and their effects on fracture conductivity are analyzed. The shale plays included in the correlations are the Barnett, Fayetteville, Marcellus, and Eagle Ford shales. Brinell hardness and compressive strength were found to be highly correlated with conductivity decline as closure stress increases. Young?s modulus was also found to be a highly significant predictor of fracture conductivity in shales. A higher modulus correlated to increased conductivity at each closure stress. It was also concluded that closure stress and proppant loading conditions have a much greater influence on fracture conductivity when compared to rock mechanical properties and fracture surface characteristics. The final correlation model presented can be used to estimate fracture conductivity in various shale plays. It is important to keep in mind the distributions of the input data into the model, as well as the experimental conditions under which the conductivity was measured when applying this correlation for prediction purposes. Advisors/Committee Members: Zhu, Ding (advisor), Hill, A Daniel (advisor), Duan, Benchun (committee member).

Subjects/Keywords: Shale; Conductivity

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

APA (6^th Edition):

Kainer, C. (2017). Predicting Hydraulic Fracture Conductivity In Shale Plays. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/165842

Chicago Manual of Style (16^th Edition):

Kainer, Cody. “Predicting Hydraulic Fracture Conductivity In Shale Plays.” 2017. Masters Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/165842.

MLA Handbook (7^th Edition):

Kainer, Cody. “Predicting Hydraulic Fracture Conductivity In Shale Plays.” 2017. Web. 26 Feb 2020.

Vancouver:

Kainer C. Predicting Hydraulic Fracture Conductivity In Shale Plays. [Internet] [Masters thesis]. Texas A&M University; 2017. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/165842.

Council of Science Editors:

Kainer C. Predicting Hydraulic Fracture Conductivity In Shale Plays. [Masters Thesis]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/165842

Texas A&M University

5. Melendez Castillo, Maria Georgina. The effects of acid contact time and rock surfaces on acid fracture conductivity.

Degree: 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1956

► The conductivity created in acid fracturing is a competition between two phenomena: etching of the rock surface and weakening of the rock. This study presents… (more)

Subjects/Keywords: acid fracturing; conductivity

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APA (6^th Edition):

Melendez Castillo, M. G. (2009). The effects of acid contact time and rock surfaces on acid fracture conductivity. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1956

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

Chicago Manual of Style (16^th Edition):

Melendez Castillo, Maria Georgina. “The effects of acid contact time and rock surfaces on acid fracture conductivity.” 2009. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-1956.

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

MLA Handbook (7^th Edition):

Melendez Castillo, Maria Georgina. “The effects of acid contact time and rock surfaces on acid fracture conductivity.” 2009. Web. 26 Feb 2020.

Vancouver:

Melendez Castillo MG. The effects of acid contact time and rock surfaces on acid fracture conductivity. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1956.

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

Council of Science Editors:

Melendez Castillo MG. The effects of acid contact time and rock surfaces on acid fracture conductivity. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1956

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

Texas A&M University

6. Enriquez Tenorio, Omar. A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity.

Degree: 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158000

► The aim of this study was to develop an understanding of the Eagle Ford shale unpropped and propped fracture conductivity. Samples were collected at Antonio… (more)

▼ The aim of this study was to develop an understanding of the Eagle Ford shale unpropped and propped fracture conductivity. Samples were collected at Antonio Creek and Lozier Canyon. Both outcrops are several hundred feet thick and extend for a few thousand feet laterally. At these locations five different geological facies (A, B, C, D and E), each with distinct lithological characteristics and geochemical properties that can be correlated to the Eagle Ford shale in the subsurface are accessible. The mineralogy of the collected samples was determined via x-ray diffraction which corroborates the relationship of the samples to the outcrops and hence to the Eagle Ford shale in the subsurface. After collected, the samples were cut into modify API conductivity cell dimensions. The fracture conductivity at different closure stresses was determined based on laboratory measurements of flow rate and pressure drops along the fracture. The fluid used in this work was nitrogen. The proppant concentration used is representative of what is commonly used in hydraulic fracturing treatments in the Eagle Ford shale. The heterogeneity of the Eagle Ford shale is addressed by obtaining conductivity samples in two different directions with respect to the bedding plane for the five geological facies. Three directions were obtained for facies B. Fracture area and fracture roughness (surface attributes) were calculated from the data taken by a surface profilometer. The mechanical properties, namely Young?s modulus, Poisson?s ratio and Brinell hardness, were experimentally determined from core plugs acquired from the same rocks where the conductivity samples were obtained. The effect that the surfaces attributes, mechanical properties and geological facies (mineralogy) have on conductivity was analyzed and the major findings of this work are the following. From this study, we found that fracture orientation has an impact on the fracture conductivity. It was also found that the geological characteristics (mineralogy) and mechanical properties (Poisson?s Ratio) impact the fracture conductivity. The geological facies (lithology) impact the fracture conductivity in Eagle Ford shale. Facies A, B and C exhibit a good relationship between fracture conductivity and surface attributes (fracture roughness and area). This relationship is not present in facies D and E. This work provides a foundation for future studies (damage mechanism) of the Eagle Ford shale fracture conductivity and gives an insight into the relationship of fracture conductivity and geological facies. Advisors/Committee Members: Zhu, Ding (advisor), Hill, Alfred D (committee member), Pope, Michael (committee member).

Subjects/Keywords: Eagle Ford; fracture conductivity

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

APA (6^th Edition):

Enriquez Tenorio, O. (2016). A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158000

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

Chicago Manual of Style (16^th Edition):

Enriquez Tenorio, Omar. “A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity.” 2016. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/158000.

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

MLA Handbook (7^th Edition):

Enriquez Tenorio, Omar. “A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity.” 2016. Web. 26 Feb 2020.

Vancouver:

Enriquez Tenorio O. A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity. [Internet] [Thesis]. Texas A&M University; 2016. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/158000.

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

Council of Science Editors:

Enriquez Tenorio O. A Comprehensive Study of the Eagle Ford Shale Fracture Conductivity. [Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158000

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

Texas A&M University

7. Lolon, Elyezer P. Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length.

Degree: 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/3050

► Low-permeability gas wells often produce less than predicted after a fracture treatment. One of the reasons for this is that fracture lengths calculated after stimulation… (more)

▼ Low-permeability gas wells often produce less than predicted after a fracture treatment. One of the reasons for this is that fracture lengths calculated after stimulation are often less than designed lengths. While actual fracture lengths may be shorter due to fracture growth out of zone, improper proppant settling, or proppant flowback, short calculated fracture lengths can also result from incorrect analysis techniques. It is known that fracturing fluid that remains in the fracture and formation after a hydraulic fracture treatment can decrease the productivity of a gas well by reducing the relative permeability to gas in the region invaded by this fluid. However, the relationships between fracture fluid cleanup, effective fracture length, and well productivity are not fully understood. In this work I used reservoir simulation to determine the relationship between fracture conductivity, fracture fluid production, effective fracture length, and well productivity. I simulated water saturation and pressure profiles around a propped fracture, tracked gas production along the length of the propped fracture, and quantified the effective fracture length (i.e., the fracture length under single-phase flow conditions that gives similar performance as for multiphase flow conditions), the "cleanup" fracture length (i.e., the fracture length corresponding to 90% cumulative gas flow rate into the fracture), and the "apparent" fracture length (i.e., the fracture length where the ratio of multiphase to single-phase gas entry rate profiles is unity). This study shows that the proppant pack is generally cleaned up and the cleanup lengths are close to designed lengths in relatively short times. Although gas is entering along entire fracture, fracturing fluid remains in the formation near the fracture. The water saturation distribution affects the gas entry rate profile, which determines the effective fracture length. Subtle changes in the gas rate entry profile can result in significant changes in effective fracture length. The results I derived from this work are consistent with prior work, namely that greater fracture conductivity results in more effective well cleanup and longer effective fracture lengths versus time. This study provides better explanation of mechanisms that affect fracturing fluid cleanup, effective fracture length, and well productivity than previous work. Advisors/Committee Members: McVay, Duane A. (advisor), Datta-Gupta, Akhil (committee member), Berg, Robert R. (committee member), Holditch, S.A. (committee member).

Subjects/Keywords: Fracture Conductivity

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APA (6^th Edition):

Lolon, E. P. (2006). Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/3050

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

Chicago Manual of Style (16^th Edition):

Lolon, Elyezer P. “Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length.” 2006. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/3050.

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

MLA Handbook (7^th Edition):

Lolon, Elyezer P. “Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length.” 2006. Web. 26 Feb 2020.

Vancouver:

Lolon EP. Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length. [Internet] [Thesis]. Texas A&M University; 2006. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/3050.

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

Council of Science Editors:

Lolon EP. Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length. [Thesis]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/3050

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

Texas A&M University

8. Marpaung, Fivman. Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test.

Degree: 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2102

► The key to producing gas from tight gas reservoirs is to create a long, highly conductive flow path, via the placement of a hydraulic fracture,… (more)

Subjects/Keywords: Gel Damage; Fracture Conductivity

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APA (6^th Edition):

Marpaung, F. (2009). Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2102

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

Chicago Manual of Style (16^th Edition):

Marpaung, Fivman. “Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test.” 2009. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2102.

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

MLA Handbook (7^th Edition):

Marpaung, Fivman. “Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test.” 2009. Web. 26 Feb 2020.

Vancouver:

Marpaung F. Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2102.

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

Council of Science Editors:

Marpaung F. Investigation of the effect of gel residue on hydraulic fracture conductivity using dynamic fracture conductivity test. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2102

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

Texas A&M University

9. Pournik, Maysam. Laboratory-scale fracture conductivity created by acid etching.

Degree: 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2361

► Success of acid fracturing treatment depends greatly on the created conductivity under closure stress. In order to have sufficient conductivity, the fracture face must be… (more)

Subjects/Keywords: Acid Fracturing; Conductivity; Roughness

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APA (6^th Edition):

Pournik, M. (2009). Laboratory-scale fracture conductivity created by acid etching. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2361

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

Chicago Manual of Style (16^th Edition):

Pournik, Maysam. “Laboratory-scale fracture conductivity created by acid etching.” 2009. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2361.

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

MLA Handbook (7^th Edition):

Pournik, Maysam. “Laboratory-scale fracture conductivity created by acid etching.” 2009. Web. 26 Feb 2020.

Vancouver:

Pournik M. Laboratory-scale fracture conductivity created by acid etching. [Internet] [Thesis]. Texas A&M University; 2009. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2361.

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

Council of Science Editors:

Pournik M. Laboratory-scale fracture conductivity created by acid etching. [Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2361

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

Texas A&M University

10. Gwak, Yunki. Thermal Transport Measurement of Silicon-Germanium Nanowires.

Degree: 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889

► Thermal properties of one dimensional nanostructures are of interest for thermoelectric energy conversion. Thermoelectric efficiency is related to non dimensional thermoelectric figure of merit, ZT=S²… (more)

▼ Thermal properties of one dimensional nanostructures are of interest for thermoelectric energy conversion. Thermoelectric efficiency is related to non dimensional thermoelectric figure of merit, ZT=S² o T/k, where S ,o , k and T are Seebeck coefficient, electrical conductivity, thermal conductivity and the absolute temperature respectively. These physical properties are interdependent. Therefore, making materials with high ZT is a very challenging task. However, nanoscale materials can overcome some of these limitations. When the size of nanomaterials is comparable to wavelength and mean free path of energy carriers, especially phonons, size effect contributes to the thermal conductivity reduction without bringing about major changes in the electrical conductivity and the Seebeck coefficient. Therefore, the figure of merit ZT can be manipulated. For example, the thermal conductivities of several silicon nanowires were more than two orders of magnitude lower than that of bulk silicon values due to the enhanced boundary scattering. Among the nanoscale semiconductor materials, Silicon-Germanium(SiGe) alloy nanowire is a promising candidate for thermoelectric materials The thermal conductivities of SiGe core-shell nanowires with core diameters of 96nm, 129nm and 177nm were measured using a batch fabricated micro device in a temperature range of 40K-450K. SiGe nanowires used in the experiment were synthesized via the Vapour-Liquid-Solid (VLS) growth method. The thermal conductivity data was compared with thermal conductivity of Si and Ge nanowires. The data was compared with SiGe alloy thin film, bulk SiGe, Si/SixGe1-x superlattice nanowire, Si/Si0.7Ge0.3 superlattice thin film and also with the thermal conductivity of Si0.5Ge0.5 calculated using the Einstein model. The thermal conductivities of these SiGe alloy nanowires observed in this work are ~20 times lower than Si nanowires, ~10 times lower than Ge nanowires, ~3-4 times lower than Si/SixGe1-x superlattice thin film, Si/SixGe1-x superlattice nanowire and about 3 time lower than bulk SiGe alloy. The low values of thermal conductivity are majorly due to the effect of alloy scattering, due to increased boundary scattering as a result of nanoscale diameters, and the interface diffuse scattering by core-shell effect. The influence of core-shell effect, alloy scattering and boundary scattering effect in reducing the thermal conductivity of these nanowires opens up opportunities for tuning thermoelectric properties which can pave way to thermoelectric materials with high figures of merit in the future. Advisors/Committee Members: Yu, Choongho (advisor), Jin, Yongmei (committee member), Karaman, Ibrahim (committee member).

Subjects/Keywords: SiGe; nanowire; thermal conductivity

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APA (6^th Edition):

Gwak, Y. (2010). Thermal Transport Measurement of Silicon-Germanium Nanowires. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889

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

Chicago Manual of Style (16^th Edition):

Gwak, Yunki. “Thermal Transport Measurement of Silicon-Germanium Nanowires.” 2010. Thesis, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889.

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

MLA Handbook (7^th Edition):

Gwak, Yunki. “Thermal Transport Measurement of Silicon-Germanium Nanowires.” 2010. Web. 26 Feb 2020.

Vancouver:

Gwak Y. Thermal Transport Measurement of Silicon-Germanium Nanowires. [Internet] [Thesis]. Texas A&M University; 2010. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889.

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

Council of Science Editors:

Gwak Y. Thermal Transport Measurement of Silicon-Germanium Nanowires. [Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-889

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

Oregon State University

11. Palmer, Ray Frederick. A direct current method for the measurement of the electrolytic conductance of solutions.

Degree: MS, Chemistry, 1950, Oregon State University

URL: http://hdl.handle.net/1957/53221

Subjects/Keywords: Electrolytes – Conductivity

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APA (6^th Edition):

Palmer, R. F. (1950). A direct current method for the measurement of the electrolytic conductance of solutions. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/53221

Chicago Manual of Style (16^th Edition):

Palmer, Ray Frederick. “A direct current method for the measurement of the electrolytic conductance of solutions.” 1950. Masters Thesis, Oregon State University. Accessed February 26, 2020. http://hdl.handle.net/1957/53221.

MLA Handbook (7^th Edition):

Palmer, Ray Frederick. “A direct current method for the measurement of the electrolytic conductance of solutions.” 1950. Web. 26 Feb 2020.

Vancouver:

Palmer RF. A direct current method for the measurement of the electrolytic conductance of solutions. [Internet] [Masters thesis]. Oregon State University; 1950. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1957/53221.

Council of Science Editors:

Palmer RF. A direct current method for the measurement of the electrolytic conductance of solutions. [Masters Thesis]. Oregon State University; 1950. Available from: http://hdl.handle.net/1957/53221

Oregon State University

12. Connors, Donald Nason. The partial equivalent conductances of salts in seawater.

Degree: PhD, Oceanography, 1967, Oregon State University

URL: http://hdl.handle.net/1957/28384

Subjects/Keywords: Electrolytes – Conductivity

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APA (6^th Edition):

Connors, D. N. (1967). The partial equivalent conductances of salts in seawater. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/28384

Chicago Manual of Style (16^th Edition):

Connors, Donald Nason. “The partial equivalent conductances of salts in seawater.” 1967. Doctoral Dissertation, Oregon State University. Accessed February 26, 2020. http://hdl.handle.net/1957/28384.

MLA Handbook (7^th Edition):

Connors, Donald Nason. “The partial equivalent conductances of salts in seawater.” 1967. Web. 26 Feb 2020.

Vancouver:

Connors DN. The partial equivalent conductances of salts in seawater. [Internet] [Doctoral dissertation]. Oregon State University; 1967. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1957/28384.

Council of Science Editors:

Connors DN. The partial equivalent conductances of salts in seawater. [Doctoral Dissertation]. Oregon State University; 1967. Available from: http://hdl.handle.net/1957/28384

University of Hong Kong

13. 曹靖楠.; Cao, Jingnan. Thermoelectric transport properties in nanoscale systems.

Degree: M. Phil., 2012, University of Hong Kong

URL: Cao, J. [曹靖楠]. (2012). Thermoelectric transport properties in nanoscale systems. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4979970 ; http://dx.doi.org/10.5353/th_b4979970 ; http://hdl.handle.net/10722/181536

►

As the fast development of nanotechnology and further industrial applications, theoretical investigations upon nanoscale devices are in urgent need. Until now several formalisms have been… (more)

▼

As the fast development of nanotechnology and further industrial applications, theoretical investigations upon nanoscale devices are in urgent need. Until now several formalisms have been well established in quantum transport of mesoscopic areas, including of tight-binding and first principle calculations. In this dissertation those methods were partly explored to explore transport and thermoelectric features in various models and actual devices. The density functional theory plus non-equilibrium Green’s function serves well in the probing process of transport properties like conductance in mesoscopic systems. Atoms’ positions were treated as the only input parameters and one computation package based on NEGF-DFT loop was utilized to get the numerical results, then the corresponding thermal quantities were analysed. The coherent transport exhibits an obvious character in transmission spectrum called transmission node, whose existence relies on the asymmetric structure of molecular junctions. In the main body of the thesis, firstly two types of model simulation were tested, and the following thermoelectric quantities showed that there’s one interesting signature in the thermopower performance, which was its temperature independence around transmission node. Through comparisons between different system parameters a rough regular pattern was obtained, that the degree of zero transmission and the energy difference around it influenced this temperature invariance feature at the same time. While these two properties were mainly determined by the natural structure of devices. Besides model simulations the ab initio investigations were also carried out. Although the actual device was not easily altered as ideal models, some similar behaviours in the transmission and thermal curves were still found out. The temperature insensitivity was considered to appear more often in a π electron dominated molecular structure rather than ones with σ electron interactions.

published_or_final_version

Physics

Master

Master of Philosophy

Advisors/Committee Members: Wang, J.

Subjects/Keywords: Electric conductivity.; Nanoelectromechanical systems.

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APA (6^th Edition):

曹靖楠.; Cao, J. (2012). Thermoelectric transport properties in nanoscale systems. (Masters Thesis). University of Hong Kong. Retrieved from Cao, J. [曹靖楠]. (2012). Thermoelectric transport properties in nanoscale systems. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4979970 ; http://dx.doi.org/10.5353/th_b4979970 ; http://hdl.handle.net/10722/181536

Chicago Manual of Style (16^th Edition):

曹靖楠.; Cao, Jingnan. “Thermoelectric transport properties in nanoscale systems.” 2012. Masters Thesis, University of Hong Kong. Accessed February 26, 2020. Cao, J. [曹靖楠]. (2012). Thermoelectric transport properties in nanoscale systems. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4979970 ; http://dx.doi.org/10.5353/th_b4979970 ; http://hdl.handle.net/10722/181536.

MLA Handbook (7^th Edition):

曹靖楠.; Cao, Jingnan. “Thermoelectric transport properties in nanoscale systems.” 2012. Web. 26 Feb 2020.

Vancouver:

曹靖楠.; Cao J. Thermoelectric transport properties in nanoscale systems. [Internet] [Masters thesis]. University of Hong Kong; 2012. [cited 2020 Feb 26]. Available from: Cao, J. [曹靖楠]. (2012). Thermoelectric transport properties in nanoscale systems. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4979970 ; http://dx.doi.org/10.5353/th_b4979970 ; http://hdl.handle.net/10722/181536.

Council of Science Editors:

曹靖楠.; Cao J. Thermoelectric transport properties in nanoscale systems. [Masters Thesis]. University of Hong Kong; 2012. Available from: Cao, J. [曹靖楠]. (2012). Thermoelectric transport properties in nanoscale systems. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4979970 ; http://dx.doi.org/10.5353/th_b4979970 ; http://hdl.handle.net/10722/181536

University of Illinois – Urbana-Champaign

14. Ghossoub, Marc G. Thermal transport in ultrathin fluoropolymer films.

Degree: MS, 0133, 2010, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/14731

► Polymers are industrially interesting materials that may contribute inexpensive solutions to nanoscale thermal transport and its numerous applications. In particular, polymers exhibit a shift in… (more)

Subjects/Keywords: Utrathin Fluorpolymers; Amorphous; Thermal Conductivity.

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APA (6^th Edition):

Ghossoub, M. G. (2010). Thermal transport in ultrathin fluoropolymer films. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/14731

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

Chicago Manual of Style (16^th Edition):

Ghossoub, Marc G. “Thermal transport in ultrathin fluoropolymer films.” 2010. Thesis, University of Illinois – Urbana-Champaign. Accessed February 26, 2020. http://hdl.handle.net/2142/14731.

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

MLA Handbook (7^th Edition):

Ghossoub, Marc G. “Thermal transport in ultrathin fluoropolymer films.” 2010. Web. 26 Feb 2020.

Vancouver:

Ghossoub MG. Thermal transport in ultrathin fluoropolymer films. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2010. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/2142/14731.

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

Council of Science Editors:

Ghossoub MG. Thermal transport in ultrathin fluoropolymer films. [Thesis]. University of Illinois – Urbana-Champaign; 2010. Available from: http://hdl.handle.net/2142/14731

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

Duquesne University

15. Morrissey, Megan M. The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus.

Degree: MS, Environmental Science and Management (ESM), 2014, Duquesne University

URL: https://dsc.duq.edu/etd/951

► Elevated total dissolved solids (TDS) have been found in streams in Pennsylvania primarily due to unconventional natural gas development (UNGD) and mine drainage. TDS is… (more)

Subjects/Keywords: Conductivity; Salinity; Total Dissolved Solids

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APA (6^th Edition):

Morrissey, M. M. (2014). The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus. (Masters Thesis). Duquesne University. Retrieved from https://dsc.duq.edu/etd/951

Chicago Manual of Style (16^th Edition):

Morrissey, Megan M. “The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus.” 2014. Masters Thesis, Duquesne University. Accessed February 26, 2020. https://dsc.duq.edu/etd/951.

MLA Handbook (7^th Edition):

Morrissey, Megan M. “The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus.” 2014. Web. 26 Feb 2020.

Vancouver:

Morrissey MM. The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus. [Internet] [Masters thesis]. Duquesne University; 2014. [cited 2020 Feb 26]. Available from: https://dsc.duq.edu/etd/951.

Council of Science Editors:

Morrissey MM. The Effects Of Elevated Total Dissolved Solids On The Behavior And Survival Of The Allegheny Mountain Dusky Salamander, Desmognathus Ochrophaeus. [Masters Thesis]. Duquesne University; 2014. Available from: https://dsc.duq.edu/etd/951

University of Newcastle

16. Azizian, Reza. A fundamental study on heat transfer characteristics of magnetite nanofluids.

Degree: PhD, 2013, University of Newcastle

URL: http://hdl.handle.net/1959.13/1038738

►

Research Doctorate - Doctor of Philosophy (PhD)

This study investigated the heat transfer behaviour of nanofluids with focus on a magnetite nanofluid as an alternative… (more)

▼

Research Doctorate - Doctor of Philosophy (PhD)

This study investigated the heat transfer behaviour of nanofluids with focus on a magnetite nanofluid as an alternative for the next generation of cooling applications. The very first aim of this study was to shed light on conflicting data reported in the literature about the thermal conductivity of conventional nanofluids (non-magnetic). For this purpose, the thermal conductivity of different nanofluid samples were measured under different conditions (namely particle volume fractions, temperature and pH) and results were compared with theoretical prediction of mixture theory. Shortcomings of different hypotheses were examined, analysed and explained. All of the experimental data were within the ±10% boundary of theoretical mixture theory (i.e. Maxwell model). It was shown that higher thermal conductivity in the conventional nanofluids can be achieved by controlling the aggregation size (i.e. pH value). To test this hypothesis, artificial aggregates were generated by applying an external magnetic field to the magnetite nanofluid. Thermal conductivity enhancement by up to 160% was observed for 0.86 vol% magnetite nanofluids (Fe3O4-water), subjected to the magnetic field intensity of 32 mT parallel to the temperature gradient. On the other hand, the thermal conductivity of magnetite nanofluid is almost constant under the applied magnetic field perpendicular to the temperature gradient. Convective heat transfer coefficient of magnetite nanofluid under laminar flow condition was also considered in the absence and presence of an external magnetic field. Heat transfer in magnetite nanofluids with and without magnetic field has been performed previously. However, the extent of the experiments and analysis is the main goal which has been achieved through this study. It has been shown that the experimental data in the absence of an external magnetic field follows the prediction of standard correlation for laminar flow heat transfer (Shah equation) using the thermophysical properties of nanofluid. Up to 300% enhancement in convective heat transfer enhancement has been observed at Re=745 and the magnetic field gradient of 32.5 mT/mm. Moreover, the effect of magnetic field on pressure drop was insignificant. It is concluded here that aggregation is the main mechanism of heat transfer in nanofluids. The thermal conductivity and convective heat transfer coefficient of magnetite nanofluids can be altered far beyond the prediction of traditional theories by applying an external magnetic field.

Advisors/Committee Members: University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering.

Subjects/Keywords: heat transfer; nanofluids; thermal conductivity

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APA (6^th Edition):

Azizian, R. (2013). A fundamental study on heat transfer characteristics of magnetite nanofluids. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1038738

Chicago Manual of Style (16^th Edition):

Azizian, Reza. “A fundamental study on heat transfer characteristics of magnetite nanofluids.” 2013. Doctoral Dissertation, University of Newcastle. Accessed February 26, 2020. http://hdl.handle.net/1959.13/1038738.

MLA Handbook (7^th Edition):

Azizian, Reza. “A fundamental study on heat transfer characteristics of magnetite nanofluids.” 2013. Web. 26 Feb 2020.

Vancouver:

Azizian R. A fundamental study on heat transfer characteristics of magnetite nanofluids. [Internet] [Doctoral dissertation]. University of Newcastle; 2013. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1959.13/1038738.

Council of Science Editors:

Azizian R. A fundamental study on heat transfer characteristics of magnetite nanofluids. [Doctoral Dissertation]. University of Newcastle; 2013. Available from: http://hdl.handle.net/1959.13/1038738

Rochester Institute of Technology

17. Alvarenga, Jack. Carbon nanotube materials for aerospace wiring.

Degree: Center for Materials Science and Engineering, 2010, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/2748

► With large amounts of time and money invested in the advancement of aerospace structures, the performance and reliability are crucial factors in the development of… (more)

Subjects/Keywords: Carbon nanotubes; Doping; Electrical conductivity

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APA (6^th Edition):

Alvarenga, J. (2010). Carbon nanotube materials for aerospace wiring. (Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/2748

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

Chicago Manual of Style (16^th Edition):

Alvarenga, Jack. “Carbon nanotube materials for aerospace wiring.” 2010. Thesis, Rochester Institute of Technology. Accessed February 26, 2020. https://scholarworks.rit.edu/theses/2748.

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

MLA Handbook (7^th Edition):

Alvarenga, Jack. “Carbon nanotube materials for aerospace wiring.” 2010. Web. 26 Feb 2020.

Vancouver:

Alvarenga J. Carbon nanotube materials for aerospace wiring. [Internet] [Thesis]. Rochester Institute of Technology; 2010. [cited 2020 Feb 26]. Available from: https://scholarworks.rit.edu/theses/2748.

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

Council of Science Editors:

Alvarenga J. Carbon nanotube materials for aerospace wiring. [Thesis]. Rochester Institute of Technology; 2010. Available from: https://scholarworks.rit.edu/theses/2748

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

Penn State University

18. Naya, Tomoki. Conductivity of Ion Exchange Materials.

Degree: MS, Energy and Mineral Engineering, 2010, Penn State University

URL: https://etda.libraries.psu.edu/catalog/10815

► Proton exchange membrane fuel cells (PEMFCs) and alkaline fuel cells (AFCs) have received much attention as two of the promising energy conversion systems which can… (more)

▼ Proton exchange membrane fuel cells (PEMFCs) and alkaline fuel cells (AFCs) have received much attention as two of the promising energy conversion systems which can be applied in many areas. In order to improve performance of the cells, the ionic conductivity of the ion exchange membranes (IEMs) have been studied by many research groups and a considerable number of IEMs and materials have been synthesized to show high conductivities in wide ranges of temperature and humidity. The measurement of ionic conductivity is crucially important in order to evaluate the performance of a newly synthesized material. Conventionally, the in-plane gas phase measurement has been used for thin-film organic membranes and the through-plane gas phase measurement has been used for inorganic-based membranes. However, the in-plane method measures the conductivity in a different direction from the operating condition of PEMFCs and AFCs. In order to overcome this problem, we applied the through-plane measurement for the thin-film membrane and compared the results with those of the conventional in-plane measurement. Similar approach was implemented for the liquid phase measurements. As a result, we found that the ionic conductivities in the membrane measured in the through-plane direction were significantly lower than those measured in the in-plane direction. Thus, we concluded that the through-plane measurement has some challenges to be solved and the through-plane measurement should be carried out more carefully than the in-plane measurement. In addition to these studies, we have investigated newly synthesized OH- conductive inorganic materials using x-ray diffraction (XRD), scanning electron microscopy (SEM), and the ionic conductivity measurement in the through-plane direction. The materials showed high conductivities comparable to other reported inorganic materials in the low temperature and low humidity ranges. However, their conductivities are much lower than the conventionally used in potassium chloride-based electrolyzers. Therefore, we need further improve the ionic conductivity of the OH- conductive inorganic materials for the development of an efficient AFC.

Subjects/Keywords: ion exchange; conductivity; fuel cell

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APA (6^th Edition):

Naya, T. (2010). Conductivity of Ion Exchange Materials. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/10815

Chicago Manual of Style (16^th Edition):

Naya, Tomoki. “Conductivity of Ion Exchange Materials.” 2010. Masters Thesis, Penn State University. Accessed February 26, 2020. https://etda.libraries.psu.edu/catalog/10815.

MLA Handbook (7^th Edition):

Naya, Tomoki. “Conductivity of Ion Exchange Materials.” 2010. Web. 26 Feb 2020.

Vancouver:

Naya T. Conductivity of Ion Exchange Materials. [Internet] [Masters thesis]. Penn State University; 2010. [cited 2020 Feb 26]. Available from: https://etda.libraries.psu.edu/catalog/10815.

Council of Science Editors:

Naya T. Conductivity of Ion Exchange Materials. [Masters Thesis]. Penn State University; 2010. Available from: https://etda.libraries.psu.edu/catalog/10815

Penn State University

19. Chen, You-han. Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics.

Degree: MS, Chemical Engineering, 2013, Penn State University

URL: https://etda.libraries.psu.edu/catalog/19733

► Nanofluids have been proposed to have superior heat transfer ability than typical coolant, but the mechanisms of thermal conductivity enhancement still remain obsecure. This study,… (more)

Subjects/Keywords: Nanofluids; Molecular Dynamics; Thermal Conductivity

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APA (6^th Edition):

Chen, Y. (2013). Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/19733

Chicago Manual of Style (16^th Edition):

Chen, You-han. “Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics.” 2013. Masters Thesis, Penn State University. Accessed February 26, 2020. https://etda.libraries.psu.edu/catalog/19733.

MLA Handbook (7^th Edition):

Chen, You-han. “Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics.” 2013. Web. 26 Feb 2020.

Vancouver:

Chen Y. Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics. [Internet] [Masters thesis]. Penn State University; 2013. [cited 2020 Feb 26]. Available from: https://etda.libraries.psu.edu/catalog/19733.

Council of Science Editors:

Chen Y. Investigating The Aggregation Effect in Nanofluids by Molecular Dynamics. [Masters Thesis]. Penn State University; 2013. Available from: https://etda.libraries.psu.edu/catalog/19733

Penn State University

20. Wubbels, Jane. Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania.

Degree: MS, Horticulture, 2010, Penn State University

URL: https://etda.libraries.psu.edu/catalog/10712

► The hydraulic architecture of a tree could contribute to its ability to tolerate drier soils by increasing resistance to xylem cavitation and improving the efficiency… (more)

Subjects/Keywords: hydraulic architecture; xylem vulnerability; conductivity

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APA (6^th Edition):

Wubbels, J. (2010). Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/10712

Chicago Manual of Style (16^th Edition):

Wubbels, Jane. “Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania.” 2010. Masters Thesis, Penn State University. Accessed February 26, 2020. https://etda.libraries.psu.edu/catalog/10712.

MLA Handbook (7^th Edition):

Wubbels, Jane. “Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania.” 2010. Web. 26 Feb 2020.

Vancouver:

Wubbels J. Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania. [Internet] [Masters thesis]. Penn State University; 2010. [cited 2020 Feb 26]. Available from: https://etda.libraries.psu.edu/catalog/10712.

Council of Science Editors:

Wubbels J. Tree species distribution in relation to stem hydraulic traits and soil moisture in a mixed hardwood forest in central Pennsylvania. [Masters Thesis]. Penn State University; 2010. Available from: https://etda.libraries.psu.edu/catalog/10712

Louisiana State University

21. Kodide, Upender. Thermal conductivity and its effects on the performance of PCC pavements in MEPDG.

Degree: MSCE, Civil and Environmental Engineering, 2010, Louisiana State University

URL: etd-11192010-111421 ; https://digitalcommons.lsu.edu/gradschool_theses/1829

► This study developed a standard thermal conductivity test procedure to test concrete specimens and studied factors influencing those specimens. The thermal conductivity of concrete is… (more)

▼ This study developed a standard thermal conductivity test procedure to test concrete specimens and studied factors influencing those specimens. The thermal conductivity of concrete is significantly affected by moisture content, type, and percentage of coarse aggregate; this finding was confirmed statistically by Analysis of Variance (ANOVA). The study also developed a model for predicting the thermal conductivity of concrete that varies with moisture content and the coarse aggregate percentage. To understand the effect of supplementary cementitious materials (SCMs), this study also measured thermal conductivity of control and ternary mixtures. An increase in thermal conductivity percentage due to increase in moisture was higher in ternary mixtures, compared to normal concrete mixture. Thermal conductivity of ternary mixtures fluctuated with change in their unit weights. An Enhanced Integrated Climatic Model (EICM) model was required to analyze the effects of the thermal conductivity of concrete on temperature and the moisture profile of pavements. An EICM model analysis showed that temperature in the middle layer of concrete pavement decreased as thermal conductivity increased, and temperatures remained constant for higher thermal conductivity values. A change in thermal conductivity had no effect on top and bottom pavement temperatures. Temperature profiles were measured in a concrete block to compare the EICM predicted temperature profile in plain cement concrete (PCC) pavements. Temperatures inside the concrete block embedded in soil at several depths were higher, compared to temperatures predicted by the EICM model. The measured temperatures attain a peak hour temperature gradient on the hottest time of the day, but the EICM model did not predict the peak hour temperature gradient. Our research performed Mechanistic Empirical Pavement Design Guide (MEPDG) analysis to estimate the effect of thermal conductivity on distresses such as cracking, faulting, and the international roughness index (IRI). We found that thermal cracking increased with decrease of thermal conductivity. We also found that an Integrated Climatic Model (ICM) stability failure occurred for a set of thermal conductivity and heat capacity readings in MEPDG analysis. Finally, this research found a strong correlation for the thermal conductivity and heat capacity values that resulting in ICM stability failure.

Subjects/Keywords: MEPDG; Thermal conductivity; PCC pavements

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APA (6^th Edition):

Kodide, U. (2010). Thermal conductivity and its effects on the performance of PCC pavements in MEPDG. (Masters Thesis). Louisiana State University. Retrieved from etd-11192010-111421 ; https://digitalcommons.lsu.edu/gradschool_theses/1829

Chicago Manual of Style (16^th Edition):

Kodide, Upender. “Thermal conductivity and its effects on the performance of PCC pavements in MEPDG.” 2010. Masters Thesis, Louisiana State University. Accessed February 26, 2020. etd-11192010-111421 ; https://digitalcommons.lsu.edu/gradschool_theses/1829.

MLA Handbook (7^th Edition):

Kodide, Upender. “Thermal conductivity and its effects on the performance of PCC pavements in MEPDG.” 2010. Web. 26 Feb 2020.

Vancouver:

Kodide U. Thermal conductivity and its effects on the performance of PCC pavements in MEPDG. [Internet] [Masters thesis]. Louisiana State University; 2010. [cited 2020 Feb 26]. Available from: etd-11192010-111421 ; https://digitalcommons.lsu.edu/gradschool_theses/1829.

Council of Science Editors:

Kodide U. Thermal conductivity and its effects on the performance of PCC pavements in MEPDG. [Masters Thesis]. Louisiana State University; 2010. Available from: etd-11192010-111421 ; https://digitalcommons.lsu.edu/gradschool_theses/1829

Louisiana State University

22. Swanhart, Samantha Lynn. Measuring soluble salts in soils via portable x-ray fluorescence spectrometry.

Degree: MS, 2013, Louisiana State University

URL: etd-11182013-111230 ; https://digitalcommons.lsu.edu/gradschool_theses/1406

► Soil scientists have been using the same quantification methods for soluble salts for decades. Yet they have long struggled with an effective method for quantifying… (more)

▼ Soil scientists have been using the same quantification methods for soluble salts for decades. Yet they have long struggled with an effective method for quantifying gypsum content, because current methods are fraught with problems. Saline soil has been historically defined as soil containing salts more soluble than gypsum (e.g., various combinations of Na+, Mg2+, Ca2+, K+, Cl-, SO42-, HCO3- and CO32-) to the extent that soil fertility is severely reduced across a wide array of climates and geological settings. Since salinity is not germane to specific soil characteristics such as texture or parent material, it can be challenging to predict salt concentrations within a profile. Given the success of previous studies using portable x-ray fluorescence (PXRF) as a tool for measuring soil characteristics, the evaluation of soluble salts in soil with PXRF seems timely. Not only does this newer technology offer more accurate, quantifiable data to investigators, it produces results in-situ, in seconds. Recent enhancements to PXRF spectrometers have provided better detection limits especially for lighter elements such as S and Cl, a key component of gypsum and other salts. Thus, this research aimed to test the effectiveness of PXRF as a means of directly quantifying gypsum and salinity in soils. A total of 102 soil samples containing a wide variety of gypsum (~2–95%) and 122 samples with various salt concentrations were subjected to both traditional laboratory analysis (thermogravimetry and electrical conductivity, respectively) and elemental analysis via PXRF. Simple and multiple linear regression were used to establish the relationship between the two data sets. Log transformation of some data sets was necessary to normalize the data. Using simple linear regression between laboratory and PXRF data, an R2 of 0.88 was produced for the gypsum data, and an R2 of 0.839 was produced for salinity data. Similarly, simple linear regression for laboratory-quantified gypsum vs. PXRF S produced an R2 of 0.91. Multiple linear regression of laboratory quantified gypsum vs. both PXRF S and Ca produced an R2 of 0.91, and 0.8669 for laboratory determined EC (dS m-1) vs. PXRF Cl, S, Ca, and K. No significant differences were observed between model generation and validation data sets. Overall, PXRF shows great promise for the direct quantification of soluble salts in soils.

Subjects/Keywords: soil; electrical conductivity; gypsum; PXRF

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APA (6^th Edition):

Swanhart, S. L. (2013). Measuring soluble salts in soils via portable x-ray fluorescence spectrometry. (Masters Thesis). Louisiana State University. Retrieved from etd-11182013-111230 ; https://digitalcommons.lsu.edu/gradschool_theses/1406

Chicago Manual of Style (16^th Edition):

Swanhart, Samantha Lynn. “Measuring soluble salts in soils via portable x-ray fluorescence spectrometry.” 2013. Masters Thesis, Louisiana State University. Accessed February 26, 2020. etd-11182013-111230 ; https://digitalcommons.lsu.edu/gradschool_theses/1406.

MLA Handbook (7^th Edition):

Swanhart, Samantha Lynn. “Measuring soluble salts in soils via portable x-ray fluorescence spectrometry.” 2013. Web. 26 Feb 2020.

Vancouver:

Swanhart SL. Measuring soluble salts in soils via portable x-ray fluorescence spectrometry. [Internet] [Masters thesis]. Louisiana State University; 2013. [cited 2020 Feb 26]. Available from: etd-11182013-111230 ; https://digitalcommons.lsu.edu/gradschool_theses/1406.

Council of Science Editors:

Swanhart SL. Measuring soluble salts in soils via portable x-ray fluorescence spectrometry. [Masters Thesis]. Louisiana State University; 2013. Available from: etd-11182013-111230 ; https://digitalcommons.lsu.edu/gradschool_theses/1406

Oregon State University

23. Brandenstein, Albert Edward. Analysis of the D. C. electric field for a pipeline in a three layered earth.

Degree: PhD, Electrical and Electronics Engineering, 1969, Oregon State University

URL: http://hdl.handle.net/1957/46345

► This paper develops an equation, from an heuristic set of assumptions, which describes the axial current, leakage current, resultant electric field, and resultant earth potential… (more)

Subjects/Keywords: Electric conductivity

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APA (6^th Edition):

Brandenstein, A. E. (1969). Analysis of the D. C. electric field for a pipeline in a three layered earth. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/46345

Chicago Manual of Style (16^th Edition):

Brandenstein, Albert Edward. “Analysis of the D. C. electric field for a pipeline in a three layered earth.” 1969. Doctoral Dissertation, Oregon State University. Accessed February 26, 2020. http://hdl.handle.net/1957/46345.

MLA Handbook (7^th Edition):

Brandenstein, Albert Edward. “Analysis of the D. C. electric field for a pipeline in a three layered earth.” 1969. Web. 26 Feb 2020.

Vancouver:

Brandenstein AE. Analysis of the D. C. electric field for a pipeline in a three layered earth. [Internet] [Doctoral dissertation]. Oregon State University; 1969. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1957/46345.

Council of Science Editors:

Brandenstein AE. Analysis of the D. C. electric field for a pipeline in a three layered earth. [Doctoral Dissertation]. Oregon State University; 1969. Available from: http://hdl.handle.net/1957/46345

Texas A&M University

24. Guerra, Jesse Mateo. Fracture Conductivity Behavior in Shale Formations.

Degree: PhD, Petroleum Engineering, 2019, Texas A&M University

URL: http://hdl.handle.net/1969.1/186178

► The objective of this study was to further the understanding of fracture conductivity and its dependence on rock mechanical properties, mineralogy, and fracture surface attributes,… (more)

▼ The objective of this study was to further the understanding of fracture conductivity and its dependence on rock mechanical properties, mineralogy, and fracture surface attributes, as well as its impairment due to flowback, based on a systematic experimental study on several mudstone formations. As part of this objective, a practical workflow was developed to extend the measured conductivity behavior to downhole stress conditions. The experimental measurements conducted in this study used mudstone samples obtained from outcrop and downhole core segments, from the Eagle Ford, the Marcellus, the Mahantango, the Middle Bakken, and the Three Forks formations. Fracture conductivity experiments were conducted utilizing a Modified API Fracture Conductivity Cell by flowing dry nitrogen and/or saline solutions representative of flowback water. As such, undamaged and water-damaged fracture conductivity was measured. Simulated fracture conditions included unpropped and propped fractures. Natural sand proppant, with a commonly used mesh size, was used with a variety of areal concentrations. Additional experiments consisted of evaluating rock mechanical properties, mineralogy, and fracture surface attributes. A large degree of heterogeneity in properties was observed for each formation. Experimental measurements showed that fracture conductivity under increasing closure stress generally follows an exponential decline rate, which is manifested as a linear relationship on a semi-log plot that is condition-specific. These functions can be representative of the formation fracture conductivity behavior, and can be extended to additional simulated fracture conditions. Furthermore, these laboratory-based measurements can be related to downhole stress conditions predicated on poroelasticity theory. This estimated in-situ fracture conductivity can be used during the performance evaluation of a hydraulically fractured horizontal well, or during the design of a new treatment. This study provides an insight into fracture conductivity and its dependence on formation physical properties. Additionally, this study presents a practical application to the measurement of fracture conductivity in mudstones and its importance in evaluating well performance. Advisors/Committee Members: Hill, A. Daniel (advisor), Zhu, Ding (committee member), Pope, Michael (committee member), Morita, Nobuo (committee member).

Subjects/Keywords: Fracture Conductivity; Shale Formations

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APA (6^th Edition):

Guerra, J. M. (2019). Fracture Conductivity Behavior in Shale Formations. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/186178

Chicago Manual of Style (16^th Edition):

Guerra, Jesse Mateo. “Fracture Conductivity Behavior in Shale Formations.” 2019. Doctoral Dissertation, Texas A&M University. Accessed February 26, 2020. http://hdl.handle.net/1969.1/186178.

MLA Handbook (7^th Edition):

Guerra, Jesse Mateo. “Fracture Conductivity Behavior in Shale Formations.” 2019. Web. 26 Feb 2020.

Vancouver:

Guerra JM. Fracture Conductivity Behavior in Shale Formations. [Internet] [Doctoral dissertation]. Texas A&M University; 2019. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1969.1/186178.

Council of Science Editors:

Guerra JM. Fracture Conductivity Behavior in Shale Formations. [Doctoral Dissertation]. Texas A&M University; 2019. Available from: http://hdl.handle.net/1969.1/186178

King Abdullah University of Science and Technology

25. Berdahl, J. Scott. Geological Effects on Lightning Strike Distributions.

Degree: 2016, King Abdullah University of Science and Technology

URL: http://hdl.handle.net/10754/610555

► Recent advances in lightning detection networks allow for detailed mapping of lightning flash locations. Longstanding rumors of geological influence on cloud-to-ground (CG) lightning distribution and… (more)

Subjects/Keywords: Lightning; Geology; Spatial statistics; Conductivity

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APA (6^th Edition):

Berdahl, J. S. (2016). Geological Effects on Lightning Strike Distributions. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/610555

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

Chicago Manual of Style (16^th Edition):

Berdahl, J Scott. “Geological Effects on Lightning Strike Distributions.” 2016. Thesis, King Abdullah University of Science and Technology. Accessed February 26, 2020. http://hdl.handle.net/10754/610555.

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

MLA Handbook (7^th Edition):

Berdahl, J Scott. “Geological Effects on Lightning Strike Distributions.” 2016. Web. 26 Feb 2020.

Vancouver:

Berdahl JS. Geological Effects on Lightning Strike Distributions. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2016. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/10754/610555.

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

Council of Science Editors:

Berdahl JS. Geological Effects on Lightning Strike Distributions. [Thesis]. King Abdullah University of Science and Technology; 2016. Available from: http://hdl.handle.net/10754/610555

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

Boise State University

26. Johnson, Brady Allen. Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow.

Degree: 2011, Boise State University

URL: https://scholarworks.boisestate.edu/td/168

► Riparian zones in semi-arid regions often exhibit high rates of evapotranspiration (ET) in spite of low soil moisture content due to vegetation that is able… (more)

▼ Riparian zones in semi-arid regions often exhibit high rates of evapotranspiration (ET) in spite of low soil moisture content due to vegetation that is able to withdraw water from shallow aquifers. This work better defines the relationship between ET and the saturated zone by comparing the observed water table drawdown to analytically modeled drawdown in fully penetrating wells of an unconfined aquifer in response to daily ET flux. ET at the Boise Hydrogeophysical Research Site or BHRS (a riparian zone in a temperate, semi arid environment) is calculated following the approach of Batra et al. (2006) but uses site (or near site) measurements for air temperature and net radiation while relying on Landsat 5 data for quantification of vegetation. The resulting ET calculations represent a data set consisting of high resolution (30m x 30m) ET flux values obtained from minimal site measurements. Water table levels in the shallow, unconfined aquifer were monitored over the summer and fall of 2009 to record the timing and magnitude of daily fluctuations in four wells with different vegetation densities and distances from the nearby Boise River at the site. ET derived from the radiation-driven model of Batra et al. (2006) compares favorably with groundwater ET contribution rates calculated from well hydrographs (White, 1932), which further supports the finding of negligible water contribution coming from the unsaturated zone in shallow riparian aquifers in semi-arid regions (Shah et al., 2007). Using an analytical solution to ET induced drawdown (Malama & Johnson, 2010) for a semi-infinite (or river bounded) domain, daily drawdown is modeled in response to daily ET flux applied at the water table. Close agreement between observed and modeled drawdown supports the idea that ET can be estimated from well hydrographs in a wellcharacterized aquifer and conversely, if ET behavior is characterized, aquifer parameters like hydraulic conductivity and specific storage can be estimated from well hydrographs.

Subjects/Keywords: Evapotranspiration; Phreatophytes; Hydraulic Conductivity; Geology

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APA (6^th Edition):

Johnson, B. A. (2011). Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow. (Thesis). Boise State University. Retrieved from https://scholarworks.boisestate.edu/td/168

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

Chicago Manual of Style (16^th Edition):

Johnson, Brady Allen. “Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow.” 2011. Thesis, Boise State University. Accessed February 26, 2020. https://scholarworks.boisestate.edu/td/168.

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

MLA Handbook (7^th Edition):

Johnson, Brady Allen. “Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow.” 2011. Web. 26 Feb 2020.

Vancouver:

Johnson BA. Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow. [Internet] [Thesis]. Boise State University; 2011. [cited 2020 Feb 26]. Available from: https://scholarworks.boisestate.edu/td/168.

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

Council of Science Editors:

Johnson BA. Evapotranspiration in the Riparian Zone of the Lower Boise River with Implications for Groundwater Flow. [Thesis]. Boise State University; 2011. Available from: https://scholarworks.boisestate.edu/td/168

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

Boston College

27. Joshi, Giri Raj. Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials.

Degree: PhD, Physics, 2010, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:101478

► Silicon germanium alloys (SiGe) have long been used in thermoelectric modules for deep-space missions to convert radio-isotope heat into electricity. They also hold promise in… (more)

▼ Silicon germanium alloys (SiGe) have long been used in thermoelectric modules for deep-space missions to convert radio-isotope heat into electricity. They also hold promise in terrestrial applications such as waste heat recovery. The performance of these materials depends on the dimensionless figure-of-merit ZT (= S2σ T/ κ), where S is the Seebeck coefficient, σ the electrical conductivity, κ the thermal conductivity, and T is the absolute temperature. Since 1960 efforts have been made to improve the ZT of SiGe alloys, with the peak ZT of n-type SiGe reaching 1 at 900 - 950 C. However, the ZT of p-type SiGe has remained low. Current space-flights run on p-type materials with a peak ZT ~ 0.5 and the best reported p-type material has a peak ZT of about 0.65. In recent years, many studies have shown a significant enhancement of ZT in other material systems by utilizing a nanostructuring approach to reduce the thermal conductivity by scattering phonons more effectively than electrons. Here we show, using a low-cost and mass-production ball milling and direct-current induced hot press compaction nanocomposite process, that a 50% improvement in the peak ZT, from 0.65 to 0.95 at 800 - 900C is achieved in p-type nanostructured SiGe bulk alloys. The ZT enhancement mainly comes from a large reduction in the thermal conductivity due to the increased phonon scattering at the grain boundaries and crystal defects formed by lattice distortion, with some contribution from the increased electron power factor at high temperatures. Moreover, nanocomposite approaches have been used to study the thermoelectric properties of other material systems such as bismuth telluride (Bi-Te), bismuth antimony (Bi-Sb), and half-Heusler phases. We observed a significant improvement in peak ZT of nanostructured p- and n-type half-Heusler compounds from 0.5 to 0.8 and 0.8 to 1.0 respectively. The ZT improvement is mainly due to the reduction of thermal conductivity. This nanostructure approach is applicable to many other thermoelectric materials that are useful for automotive, industrial waste heat recovery, space power generation, or solar power conversion applications. Advisors/Committee Members: Zhifeng Ren (Thesis advisor).

Subjects/Keywords: Nanocomposite; Thermal conductivity; Thermoelectrics

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APA (6^th Edition):

Joshi, G. R. (2010). Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101478

Chicago Manual of Style (16^th Edition):

Joshi, Giri Raj. “Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials.” 2010. Doctoral Dissertation, Boston College. Accessed February 26, 2020. http://dlib.bc.edu/islandora/object/bc-ir:101478.

MLA Handbook (7^th Edition):

Joshi, Giri Raj. “Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials.” 2010. Web. 26 Feb 2020.

Vancouver:

Joshi GR. Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials. [Internet] [Doctoral dissertation]. Boston College; 2010. [cited 2020 Feb 26]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101478.

Council of Science Editors:

Joshi GR. Study of Thermoelectric Properties of Nanostructured P-Type Si-Ge, Bi-Te, Bi-Sb, and Half-Heusler Bulk Materials. [Doctoral Dissertation]. Boston College; 2010. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101478

Cornell University

28. Smith, Maria. Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests .

Degree: 2014, Cornell University

URL: http://hdl.handle.net/1813/36134

► Non-native woody plants pose significant threats to biodiversity, and thus ecosystem goods and services. Many non-natives exhibit suites of traits such as higher productivity, which… (more)

Subjects/Keywords: phenology; root dynamics; hydraulic conductivity

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APA (6^th Edition):

Smith, M. (2014). Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests . (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/36134

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

Chicago Manual of Style (16^th Edition):

Smith, Maria. “Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests .” 2014. Thesis, Cornell University. Accessed February 26, 2020. http://hdl.handle.net/1813/36134.

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

MLA Handbook (7^th Edition):

Smith, Maria. “Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests .” 2014. Web. 26 Feb 2020.

Vancouver:

Smith M. Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests . [Internet] [Thesis]. Cornell University; 2014. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/1813/36134.

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

Council of Science Editors:

Smith M. Linking Stem And Leaf Traits To Leaf Phenology In Native And Non-Native Woody Plants Of Eastern Deciduous Forests . [Thesis]. Cornell University; 2014. Available from: http://hdl.handle.net/1813/36134

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

University of Ottawa

29. Yu, Shuaibo. Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites .

Degree: 2014, University of Ottawa

URL: http://hdl.handle.net/10393/31447

► Polymer nanocomposites are prepared by appropriately dispersing nanoscale fillers into polymer matrices. Graphene, a two-dimensional nano-carbon material with outstanding physical properties, has been widely studied… (more)

Subjects/Keywords: Graphene; Nanocomposite; Electrical conductivity

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APA (6^th Edition):

Yu, S. (2014). Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/31447

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

Chicago Manual of Style (16^th Edition):

Yu, Shuaibo. “Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites .” 2014. Thesis, University of Ottawa. Accessed February 26, 2020. http://hdl.handle.net/10393/31447.

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

MLA Handbook (7^th Edition):

Yu, Shuaibo. “Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites .” 2014. Web. 26 Feb 2020.

Vancouver:

Yu S. Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites . [Internet] [Thesis]. University of Ottawa; 2014. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/10393/31447.

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

Council of Science Editors:

Yu S. Study of Electrical Conductivity of Epoxy/Graphene Platelet Nanocomposites . [Thesis]. University of Ottawa; 2014. Available from: http://hdl.handle.net/10393/31447

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

University of Waterloo

30. Wong, Joanne. Synthesis and Characterization of Multiband Neutral Radicals.

Degree: 2014, University of Waterloo

URL: http://hdl.handle.net/10012/8967

► The notion that an array of free radicals might behave like metallic sodium was first suggested by McCoy and Moore in 1911. While the hypothesis… (more)

▼ The notion that an array of free radicals might behave like metallic sodium was first suggested by McCoy and Moore in 1911. While the hypothesis represents an important historical landmark, there are many synthetic challenges associated with designing a conductive radical, such as the high propensity for these materials to dimerize and thus quench the free spin. Considerable advances have been made to overcome spin-pairing, including incorporation of heteroatoms such as sulfur and nitrogen atoms. Over the last 20 years, the Oakley group has used thiazyl radicals as a building block for multifunctional materials. While the early frameworks possessed a high barrier to charge transport, U, trapping the materials in Mott insulating states, the development of resonance-stabilized oxobenzene-bridged bisdithiazolyl radicals has led to a significant decrease in U, and metallic conductivity under mild pressure have also been observed. The focus of this thesis is on the design, synthesis, and characterization of new oxobenzene-bridged radicals, and the effects of pressure on these systems. One particularly interesting system is the prototypal-oxobenzene-bridged radical, in which compression from 0 – 13 GPa afforded two additional phases and a significant increase in conductivity, peaking at 2 S cm-1 at 6 GPa with a concomitant decrease in Eact to zero, consistent with formation of a metallic state. Density functional theory (DFT) calculations were used to probe the electronic structure of these oxobenzene-bridged radicals, and these revealed the multiband electronic structure which is the source of the superior physical properties of these materials compared to previous generations of thiazyl radicals. The intrinsically low U values and diverse structural variety exhibited by these oxobenzene-bridged radicals prompted the study of other substituents at the basal site. Studies on the early monocyclic DTDA systems were explored in pursuit of structure-directing ligands which can alter the solid-state packing to improve the bandwidth W. To this end, a pyridyl moiety was incorporated onto the DTDA framework, in which molecular ribbons laced together laterally by S – N intermolecular contacts was observed. However, these radicals crystallize as diamagnetic dimers, and are insulators. Nevertheless, it was established that nitrogen can be used as a structure directing ligand. Consequently, incorporation of a pyridine-quinone core into the oxobenzene-bridged framework was pursued in hopes of generating a more tightly bound structure with improved bandwidth, W. While the synthesis of the radical was not achieved, a variety of new synthetic procedures and novel species were developed. The last and most recent work involves the incorporation of a π-acceptor (i.e. NO2) at the basal site of the oxobenzene-bridged framework, and the resulting material displays the lowest Ecell (U) = 0.45 V ever observed for a neutral radical. While this is still ongoing work, preliminary results on the synthesis, crystallography, magnetic and…

Subjects/Keywords: neutral radicals; conductivity; magnetism; bisdithiazolyl

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APA (6^th Edition):

Wong, J. (2014). Synthesis and Characterization of Multiband Neutral Radicals. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/8967

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

Chicago Manual of Style (16^th Edition):

Wong, Joanne. “Synthesis and Characterization of Multiband Neutral Radicals.” 2014. Thesis, University of Waterloo. Accessed February 26, 2020. http://hdl.handle.net/10012/8967.

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

MLA Handbook (7^th Edition):

Wong, Joanne. “Synthesis and Characterization of Multiband Neutral Radicals.” 2014. Web. 26 Feb 2020.

Vancouver:

Wong J. Synthesis and Characterization of Multiband Neutral Radicals. [Internet] [Thesis]. University of Waterloo; 2014. [cited 2020 Feb 26]. Available from: http://hdl.handle.net/10012/8967.

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

Council of Science Editors:

Wong J. Synthesis and Characterization of Multiband Neutral Radicals. [Thesis]. University of Waterloo; 2014. Available from: http://hdl.handle.net/10012/8967

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

Open Access Theses and Dissertations