Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.Ch.E.)--University of Delaware, 2006. / Principal faculty advisor: Jingguang G. Chen. Includes bibliographical references.

The miniaturization of energy, chemical and biological systems for distributed and portable applications, known as process intensification, is realized by the enhancement in heat and mass transfer performance within high surface-to-volume ratio microchannels. Fabrication of devices for process intensification is achieved in part by microlamination techniques. These techniques consist of patterning, aligning, and bonding thin layers of material into monolithic devices. Even though the fabrication techniques used in microlamination are generally accurate and consistent, small amounts of dimensional variation in microlaminated structures can strongly affect the device performance. One significant finding of this dissertation is that fin warpage, which is commonly induced during bonding, generally has more adverse device performance effects than misalignment. A heat exchanger that contains fin warpage as small as 25 percent of the microchannel height (on the order of 10 ��m) needs to almost double the number of flow channels to gain the same thermal effectiveness as the uniform one. Therefore, the focus of this dissertation is to investigate, understand, and learn how to control the cause and effect of buckling warpage produced within microlaminated structures. The microlamination discussed in this dissertation is performed with a thermally-controlled registration process, which facilitates metallic bonding at elevated temperatures. Another finding of this dissertation is that the tolerance limits of the fixture used in this registration process exceed the accuracy of the machine tools used to produce the fixture. Fixture tolerance limits on the order of 10 ��m are necessary to align and bond laminae with thicknesses below 100 ��m. An alternative technique based on the compliance of the fixture is proposed in order to improve these limits. This technique helps compensate for the excessive registration force due to over-constrained bonding, which extends the range of fixture tolerance limit to over 100 ��m well within current process capability of machine tools. Another approach to controlling fin warpage, based on the induction of higher modes of fin buckling, is also discussed. An analytical evaluation shows that the effect of fin warpage is minor as the mode of buckling reaches mode 10. A preliminary experiment confirms that the induction of fin buckling into a higher mode can be achieved by constraining the fin at specific locations along the fin during microlamination. / Graduation date: 2002

Thesis (D.Eng.)--University of Delaware, 2008. / Principal faculty advisors: Jingguang G. Chen and Mark A. Barteau, Dept. of Chemical Engineering. Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references. Also available in electronic version.

Thesis (Ph. D.)--Oregon State University, 2006. / Printout. Includes bibliographical references. Also available on the World Wide Web.

1.1\xMagnetic nanoparticles (NPs) with sizes ranging from 2 to 20 nm in diameter represent an important class of artificial nanostructured materials, since the NP size is comparable to the size of a magnetic domain. They have potential applications in data storage, catalysis, permanent magnetic nanocomposites, and biomedicine.;1.2\xTo begin with, a brief overview on the background of Fe-based bimetallic NPs and their applications for data-storage and catalysis was presented in Chapter 1.;1.3\xIn Chapter 2, L10-ordered FePt NPs with high coercivity were directly prepared from a novel bimetallic acetylenic alternating copolymer P3 by a one-step pyrolysis method without post-thermal annealing. The chemical ordering, morphology and magnetic properties were studied. Magnetic measurements showed that a record coercivity of 3.6 T (1 T = 10 kOe) was obtained in FePt NPs. By comparison of the resultant FePt NPs synthesized under Ar and Ar/H2, the characterization proved that the incorporation of H2 would affect the nucleation and promote the growth of FePt NPs. The L10 FePt NPs were also successfully patterned on Si substrate by nanoimprinting lihthography (NIL). The highly ordered ferromagnetic arrays on a desired substrate for bit-patterned media (BPM) were studied and promised bright prospects for the progress of data-storage.;1.4\xFuthermore, we also reported a new FePt-containing metallopolymer P4 as the single-source precursor for metal alloy NPs synthesis, where the metal fractions were on the side chain and the ratio could be easily controlled. This polymer was synthesized from random copolymer poly(styrene-4-ethynylstyrene) PES-PS and bimetallic precursor TPy-FePt ([Pt(4-ferrocenyl-(NN̂N̂))Cl]Cl) by Sonogashira coupling reaction. After pyrolysis of P4, the stoichiometry of Fe and Pt atoms in the synthesized NPs (NPs) is nearly close to 1:1, which is more precise than using TPy-FePt as precursor. Polymer P4 was also more favorable for patterning by high throughout NIL as compared to TPy-FePt. Ferromagnetic nanolines, potentially as bit-patterned magnetic recording media, were successfully fabricated from P4 and fully characterized.;1.6\xBesides, a bimetallic complex TPy-FePd-2 was prepared and used as a single-source precursor to synthesize ferromagnetic FePd NPs by one-pot pyrolysis. The resultant FePd NPs have a mean size of 19.8 nm and show the coercivity of 1.02 kOe. In addition, the functional group (-NCMe) in TPy-FePd-2 was easily substituted by a pyridyl group. A random copolymer PS-P4VP was used to coordinate with TPy-FePd-2, and the as-synthesized polymer made the metal fraction disperse evenly along the flexible chain. Fabrication of FePd NPs from the polymers was also investigated, and the size could be easily controlled by tuning the metal fraction in polymer. FePd NPs with the mean size of 10.9, 14.2 and 17.9 nm were prepared from the metallopolymer with 5 wt%, 10 wt% and 20wt% of metal fractions, respectively.;1.7\xIn Chapter 4, molybdenum disulfide (MoS2) monolayers decorated with ferromagnetic FeCo NPs on the edges were synthesized through a one-step pyrolysis of precursor molecules in an argon atmosphere. The FeCo precursor was spin coated on the MoS2 monolayer grown on Si/SiO2 substrate. Highly-ordered body-centered cubic (bcc) FeCo NPs were revealed under optimized pyrolysis conditions, possessing coercivity up to 1000 Oe at room temperature. The FeCo NPs were well-positioned along the edge sites of MoS2 monolayers. The vibration modes of Mo and S atoms were confined after FeCo NPs decoration, as characterized by Raman shift spectroscopy. These MoS2 monolayers decorated with ferromagnetic FeCo NPs can be used for novel catalytic materials with magnetic recycling capabilities. The sizes of NPs grown on MoS2 monolayers are more uniform than from other preparation routines. Finally, the optimized pyrolysis temperature and conditions provide receipts for decorating related noble catalytic materials.;1.8\xFinally, Chapters 5 and 6 present the concluding remarks and the experimental details of the work described in Chapters 2-4.

Thesis (Ph. D.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by Mark G. Allen. / Vita. Includes bibliographical references (leaves 155-166).

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