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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Atomic force microscopy study of nano-confined liquids

Li, Tai-De 19 August 2008 (has links)
In this thesis, we investigate the structural and dynamical properties of nano-confined liquids by means of a new AFM-based technique that has the ability to measure normal force, lateral force, and the distance between the AFM tip and the sample simultaneously. Thanks to the mechanical stability of our apparatus, a judicious choice, and a new mechanical drift analysis, we are able to measure the tip-sample distance with sub-angstrom resolution, all the way down to the last liquid layer.
372

Role of carbon dioxide in gas expanded liquids for removal of photoresist and etch residue

Song, Ingu 08 October 2007 (has links)
Progress in the microelectronics industry is driven by smaller and faster transistors. As feature sizes in integrated circuits become smaller and liquid chemical waste becomes an even greater environmental concern, gas expanded liquids (GXLs) may provide a possible solution to future device fabrication limitations relative to the use of liquids. The properties of GXLs such as surface tension can be tuned by the inclusion of high pressure gases; thereby, the reduced surface tension will allow penetration of cleaning solutions into small features on the nanometer scale. In addition, the inclusion of the gas decreases the amount of liquid necessary for the photoresist and etch residue removal processes. This thesis explores the role of CO2-based GXLs for photoresist and etch residue removal. The gas used for expansion is CO2 while the liquid used is methanol. The cosolvent serving as the removal agent is tetramethyl ammonium hydroxide (TMAH) which upon reacting with CO2 becomes predominantly tetramethyl ammonium bicarbonate (TMAB).
373

Electrochemical comparison and deposition of lithium and potassium from phosphonium- and ammonium-tfsi ionic liquids

Vega, Jose A. 09 April 2009 (has links)
In this work, ionic liquids (ILs) were investigated for use as battery electrolytes. The ILs were synthesized from quaternary ammonium and phosphonium salts and TFSI-. A dendrite free lithium metal anode was demonstrated by deposition of a lithium-potassium alloy. Several phosphonium ILs were synthesized using the TFSI- and PF6- anions until a room temperature IL was obtained. The smaller size, highly symmetric PF6- anion yielded high melting point salts, while TFSI- yielded much lower melting point ILs. When a room temperature IL, Bu3HexP+TFSI-, was obtained the analogous ammonium IL, Bu3HexP+TFSI-, was synthesized and compared. The phosphonium-based ionic liquid showed improved stability and physical properties compared to the analogous ammonium-based IL. The phosphonium-based IL had higher conductivity, 0.43 mS/cm, than the ammonium-based IL, 0.28 mS/cm. The addition of LiTFSI to both ILs led to a decrease in conductivity and increase in viscosity. The lower viscosity and higher stability of the phosphonium-based IL led to higher current density and stability for electrodeposited lithium metal. IL reduction interfered with lithium deposition reflecting lower coulombic efficiencies and giving the appearance of an unstable lithium couple. An optimum deposition potential was found which was bounded by the electrochemical stability of each IL. The stability of lithium in the ILs increased at lower temperature due to slower reactivity with the IL. Addition of higher quantities of lithium ions caused a higher fraction of the cathodic current going to lithium deposition that was reoxidized. The stability of lithium in the ILs increased at lower temperature due to slower reactivity with the IL. The electrodeposition and reoxidation of potassium was also demonstrated. Deposition of a lithium-potassium alloy caused slight increases in the cathodic and anodic currents along with higher coulombic efficiencies. Also, it was found that a lithium-potassium alloy could be deposited at high current for long times without the occurrence of dendrites.
374

Design and manufacture of an experimental system for the analysis of splashing and freezing phenomena /

Ermenc, Mark, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2002. / Includes bibliographical references (p. 109-111). Also available in electronic format on the Internet.
375

Investigating capillary pressure and interfacial area for multiphase flow in porous media using pore-scale imaging and lattice-Boltzmann modeling /

Porter, Mark L. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 113-127). Also available on the World Wide Web.
376

3D numerical modeling of dry/wet contact mechanics for rough, multilayered elastic-plastic solid surfaces and effects of hydrophilicity/hydrophobicity during separation with applications

Cai, Shaobiao, January 2008 (has links)
Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 189-198).
377

Flexographic deinking with electric field technology by destabilization and flotation

Shemi, Akpojotor January 2008 (has links)
Thesis (Ph.D.)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Hsieh, Jeffery; Committee Member: Breedveld, Victor; Committee Member: Empie, Jeff; Committee Member: Forney, Larry; Committee Member: Singh, Preet
378

Interaction of liquid droplets with low-temperature, low-pressure plasma

Jones, Tony Lee. January 2005 (has links)
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2005. / Said I. Abdel-Khalik, Committee Chair ; Sheldon M. Jeter, Committee Member ; Minami Yoda, Committee Member. Includes bibliographical references.
379

Inverse modeling of subsurface environmental partitioning tracer tests /

Nicot, Jean-Philippe, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 418-432). Available also in a digital version from Dissertation Abstracts.
380

Design of a field scale project for surfactant enhanced remediation of a DNAPL contaminated aquifer

Brown, Chrissi Lynn, McKinney, Daene C. Pope, G. A. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Daene C. McKinney and Gary A. Pope. Vita. Includes bibliographical references.

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