Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994. / Includes bibliographical references (leaves 214-223). / by Frederick George Haubensak. / Ph.D.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008. / Includes bibliographical references (leaf 24). / A study of the behavior of nanoparticles in the presence of solvent vapors is presented. Millimeter-scale films of gold nanoparticles, one nanometer thick, are treated with solvent vapors at various temperatures and the behavior of the nanoparticles is tracked over time using transmission electron microscopy. The ultimate goal of this processing is to repair defects such as grains, dislocations, and vacancies in the original superlattice. Additionally, Langmuir-Schaeffer films of gold nanoparticles on water surfaces are subjected to thermal and ultrasonic treatment in an attempt to correct defects in the films, which are then transferred to solid substrates for observation. Unfortunately, none of these approaches is able to reduce the defect concentration in a lattice, although thermal treatment and sonication of Langmuir-Schaeffer nanoparticle films are found to provide a controllable approach to depositing exact double layers of nanoparticles. / by Vladimir Tarasov. / S.B.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008. / Includes bibliographical references (leaves 66-69). / Cancer immunotherapy attempts to stimulate the immune system to reject and destroy tumor cells. Despite the amount of ongoing intensive research to prevent cancer, tumor cells continue to evade immune responses. Currently, dendritic cell vaccines are in development, in which autologous antigen-loaded dendritic cells are injected back into the patient in order to generate an appropriate immune response. Improving upon this idea, members of the Irvine laboratory are in development of an injectable dendritic cell based formulation that gels in situ around the tumor site. In this way, immune cells (most notably T cells) can be recruited and become activated against specific tumor antigens, and (hopefully) kill tumor cells. Recent studies have shown the potential benefit of incorporation of cytokine interleukin-15 complexed with its soluble receptor interleukin-5R[alpha], which is discussed. Economic considerations are also discussed, including topics such as intellectual property, barriers to entry, initial markets and market drivers, and entry into the current supply chain considerations. A business strategy is outlined and evaluated. / by Andrew Song. / M.Eng.

Thesis: Sc. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2014. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 321-324). / Block copolymers (BCPs) have become a highly studied material for lithographic applications due to their ability to self-assemble into complex periodic patterns with feature resolutions ranging from a few to 100s nm. BCPs form a wide variety of patterns due the combination of their enthalpic interactions promoting immiscibility between the blocks and the bonding constraint through their chain topology. The morphologies formed can be tailored through a directed self-assembly (DSA) process using chemical or topographical templates to achieve a desired thin film pattern. This method combines the traditional top-down lithographic methods with the bottom-up self-assembly process to obtain greater control over long range order, the local morphology, and overall throughput of the patterns produced. This work looks at key modeling challenges in optimizing BCP DSA to achieve precision morphology control, reproducibility, and defect control. Modeling techniques based on field theoretic simulations are used to both characterize and predict the morphological behavior of a variety of BCPs under a variety of processing conditions including solvent annealing and DSA under topographical boundary conditions. These methods aid experimental studies by saving time in performing experiments over wide parameter spaces as well as elucidating information that may not be available by current experimental techniques. Both forward simulation approaches are studied where parameters are varied over a wide range with phase diagrams of potential morphologies characterized and inverse design approaches where given target patterns are taken as simulation input and required conditions to produce those patterns are outputted from the simulation for experimental testing. The studies ultimately help identify the key control parameters in BCP DSA and enable a vast array of possible utility in the field. / by Adam Floyd Hannon. / Sc. D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1984. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / by Christine A. Wang. / Ph.D.

Thesis: S.B., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 35-36). / Redox-mediated separation systems offer the potential to efficiently desalinate water and to purify contaminated waste streams, among other health and environmental applications. A TCAQ-based polymer, unique for its two-electron redox reaction, was synthesized for use in redox-mediated separation systems, and its performance was quantified in low-concentration aqueous salt solutions. The polyvinyl ferrocene (PVF)//PTCAQ system displayed an ion adsorption capacity much higher than previously reported literature values for capacitive or redox deionization systems. / by Emily Thai. / S.B.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1990. / Includes bibliographical references (leaves 210-222). / by Jaeshin Cho. / Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003. / Includes bibliographical references (p. 303-311). / Using first principles calculations the effect of electronic structure on the stability of positive electrode materials for lithium rechargeable batteries is investigated. The investigation focuses upon lithiated α-NaFeO₂ type 3d transition metal oxide structures. It is found that the ligand field stabilization energy (LFSE) is of particular importance in stabilizing the α-NaFeO₂ type layered structure with general formula Li[sub]x MO₂ (0 <[or equal to] x <[or equal to] 1 and M = Co, Fe, Mn, Ni, ...) at partial lithiation. The key quantity is found to be the difference in LFSE between the 3d metal ion in tetrahedral coordination and octahedral coordination in the cubic close packed (CCP) oxygen framework. If the change in LFSE is small, then the migration of 3d transition metal ions between tetrahedral and octahedral sites generally involves less variation in energy, and hence is easier. This facilitates diffusion of the 3d transition metal ions through the CCP oxygen framework and tends to destabilize the layered structure at partial lithiation. Layered lithium manganese oxide is given particular attention as a material that rapidly transforms to a spinel-like structure with electrochemical cycling. Focus is also placed upon layered lithium cobalt oxide as a material that remains stable in the layered structure with electrochemical cycling. The differing stability of these compounds in the layered structure is explained in terms of LFSE. Spin pairing energy (SPE) is also found to make an important contribution to the energetics of low spin transition metal oxides like lithium cobalt oxide. The influence of SPE on structural stability, as well as other aspects of transition metal electronic structure, are addressed as well. The importance of LFSE, and hence valence, on the stability of the layered structure recommends various doping strategies. In the case of lithium manganese oxide it is found that dopants which decrease the filling of the Mn e[sub]g orbitals stabilize Mn in octahedral coordination, and hence stabilize the layered structure. Dopants which produce this effect are identified as low charge fixed valence ions like Li+, A1³+, Mg²+, or elements with greater electronegativity than Mn³+ such as Ni²+, Co³+, or Cr³+. / by John Stuart Reed. / Ph.D.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005. / Includes bibliographical references (leaves 30-32). / The solubility of mixed monolayer protected gold nanoparticles was studied. Monolayer protected metal nanoparticles are attractive materials because of the optical and electronic properties of their metal cores and because of the surface properties of their ligand coating. Recently, it was discovered that a mixture of ligands phase separate into ordered domains of single nanometer or subnanometer width on the surface of metal nanoparticles. The morphology and length of the ligand domains (which take the form of ripples on the particle surface) has given these nanoparticles novel properties. Because monolayer protected nanoparticles can be dissolved and dried many times, they can be handled and processed in ways not available to other nanomaterials. Understanding the solubility of mixed monolayer protected metal nanoparticles could help in implementing their unique new properties. This study demonstrates that the solubility of these particles in organic solvents cannot be explained only in terms of the composition of the ligand shell. Instead, solubility is also closely linked to morphology of the ligand shell via relationships between the size of the solvent molecule and the size of the features in the morphology. / by Jacob W. Myerson. / S.B.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2012. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Cataloged from student submitted PDF version of thesis. / Includes bibliographical references (p. 207-216). / Liquid foams are dispersions of bubbles in a liquid. Bubbles are stabilized by foaming agents that position at the interface between the gas and the liquid. Most foaming agents, such as the commonly used sodium dodecylsulfate, are surfactant molecules with linear or branched chain molecular structures. This thesis presents a new class of liquid foams made with a foaming agent having a sheet molecular structure. In these foams, air bubbles are encapsulated inside graphene shells. The shells have a concentric layered structure made of isophorone diamine modified graphene oxide sheets. The liquid foams of graphene were initially developed as an extractive step in the preparation of graphene-epoxy nanocomposites. Chapter 1 gives an introduction to polymer nanocomposites and graphene. Chapter 2 presents a novel processing method for graphene-epoxy nanocomposites. Chapter 3 deals with the structure, formation mechanism, stability and mechanical properties of the liquid foams of graphene. Chapter 4 reports on materials and methods. Finally, Chapter 5 summarizes the main conclusions of this work and proposes future directions for research. / by Daniel Alcazar Jorba. / Ph.D.