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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.
251

Synthesis and Characterization of Iso-Reticular Metal-Organic Frameworks and Their Applications for Gas Separations

Yoo, Yeonshick 2010 August 1900 (has links)
Nanoporous metal-organic frameworks (MOFs) have attracted tremendous interest due to their potential applications in gas-storage, gas separation, gas sensing, and catalysis. MOFs consist of metal-oxygen polyhedera interconnected with a variety of organic linker molecules, resulting in tailored nanoporous materials. With a judicious choice of organic linker groups, it is possible to fine-tune size, shape, and chemical functionality of the cavities and the internal surfaces. This unique structural feature offers unprecedented opportunities in small-molecule separations as well as chiral separations and catalysis. Prototypical iso-reticular metal-organic frameworks (IRMOFs) have been extensively studied among MOFs due to the simplicity of their synthesis and the variety of their potential applications. IRMOFs are a specific series of metal-organic frameworks developed by Yaghi and his coworkers. All IRMOFs are composed of oxygen-centered Zn4O tetrahedra interconnected with dicarboxylate linkers, forming a cubic type three dimensional (3D) porous network with high surface area. Despite a great deal of research in the synthesis and characterization of MOFs, there have been relatively few reports on the development of their applications, such as the fabrication of MOF thin films and membranes for gas separations. This is mainly due to the challenges associated with relatively difficult heterogeneous nucleation (seeding) and growth of MOFs on supports, and crack formation compared to their counterparts. Thin films and membranes of MOFs have great potentials for applications in membranebased gas separations, reactors, chemical sensors, and nonlinear optical devices. In this dissertation, the fabrication of IRMOF-1 membrane using a novel seeding method and its gas diffusion properties has been demonstrated. Introduction of the new seeding method for MOFs using microwaves resulted in well inter-grown IRMOF membranes showing Knudsen type transport of small gases through its pore. The heteroepitaxial growth of one IRMOF on another produced multi-layered IRMOF membranes. In addition, postsynthetic modification (PSM) of IRMOFs created functionalized membranes with enhanced stability against water as well as reduced crack formation during membrane fabrication. Lastly, hierarchical IRMOFs with improved CO2 adsorption properties were synthesized via PSM with cyanuric chloride.
252

Carbon membranes for challenging gas separations /

Steel, Keisha Marie, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 176-179). Available also in a digital version from Dissertation Abstracts.
253

Polyelectrolytes in analytical separations

Howell, Peter B. Schlenoff, Joseph B. January 2002 (has links)
Thesis (Ph. D.)--Florida State University, 2002. / Advisor: Dr. Joseph B. Schlenoff, Florida State University, College of Arts and Sciences, Dept. of Chemistry. Title and description from dissertation home page (viewed Sept. 29, 2003). Includes bibliographical references.
254

Transport of gases across membranes /

Mokrani, Touhami. January 1900 (has links)
Thesis (MTech (Chemical Engineering))--Peninsula Technikon, 2000. / Word processed copy. Summary in English. Includes bibliographical references. Also available online.
255

Evaluation of X-ray imaging to investigate hydraulic performance of vapor-liquid contactors

Schmit, Carolyn Elizabeth 28 August 2008 (has links)
Not available / text
256

Phase separation in poly (styrene-b-ethylene oxide) thin films on different substrates

To, Chin-nang, Titan., 杜展能. January 2003 (has links)
published_or_final_version / abstract / toc / Physics / Master / Master of Philosophy
257

Process synthesis of optimal and near optimal distillation networks

Shoaei, Mahnoosh 12 1900 (has links)
No description available.
258

Process optimization and properties of protein concentrates from brewers' spent grain

Diptee, Rosemarie January 1989 (has links)
No description available.
259

Decay of mass-separated [superscript]195Bi to levels in [superscript]195Pb : collinear laser spectroscopy on mass-separated neutron-deficient lead isotopes

Griffin, Jeffrey Cliff 08 1900 (has links)
No description available.
260

Preliminary crystallization and characterization of lectin-sugar complex

Li, Mi 05 1900 (has links)
No description available.

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