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‣ The effects of carburizing environments on elevated temperature fatigue crack growth behavior in the nickel-base superalloy nimonic 115

White, Carl J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 111 leaves; 9875747 bytes; 9875510 bytes; application/pdf; application/pdf
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by Carl J. White.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1981.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Includes bibliographical references.

‣ The adsorption of glyceryl esters at the alumina/toluene interface

Tormey, E. S. (Ellen Schwartz)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 349 leaves; 22577443 bytes; 22577203 bytes; application/pdf; application/pdf
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by Ellen Schwartz Tormey.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Vita.; Includes bibliographical references.

‣ Cracking of cold drawn resulfurized type 303 hexagon bars

Gault, Paul Alan
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 55 leaves; 3122805 bytes; 3122563 bytes; application/pdf; application/pdf
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by Paul Alan Gault.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

‣ Activated sintering of bismuth-doped zinc oxide ceramics

Rothman, Elaine Paula
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 83 leaves; 5231034 bytes; 5230793 bytes; application/pdf; application/pdf
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by Elaine Paula Rothman.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Vita.; Includes bibliographical references.

‣ Symmetry principles in the physics of crystalline interfaces

Kalonji, Gretchen Lynn
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 113 leaves; 5706553 bytes; 5706314 bytes; application/pdf; application/pdf
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by Gretchen Lynn Kalonji.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

‣ Surface chemical modification of polyaramid filaments with amine plasmas

Allred, Ronald Edward
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 186 [i.e. 187] leaves; 11283796 bytes; 11283552 bytes; application/pdf; application/pdf
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by Ronald Edward Allred.; Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

‣ Fatigue properties of rail steels

Journet, Bertrand
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 116 leaves; 5904304 bytes; 5904065 bytes; application/pdf; application/pdf
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by Bertrand Journet.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Includes bibliographical references.

‣ Resistance spot welding of galvanized steel sheet

Gedeon, Steven Anthony
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 253 leaves; 12419879 bytes; 12419633 bytes; application/pdf; application/pdf
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by Steven Anthony Gedeon.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1984.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Vita.; Includes bibliographical references.

‣ Application of multi-attribute utility analysis to problems in materials selection

Field, Frank Remsen
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 231 leaves; 10336763 bytes; 10336517 bytes; application/pdf; application/pdf
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by Frank Remsen Field III.; Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Material Science and Engineering, 1985.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Vita.; Bibliography: leaves 208-229.

‣ TEM study of dislocation structure in grain boundaries in metals

Kvam, Eric Peter
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 155 leaves; 8492500 bytes; 8492257 bytes; application/pdf; application/pdf
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by Eric Peter Kvam.; Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1985.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Vita.; Bibliography: leaves 150-154.

‣ Mechanical degradation of a polyurethane elastomer

Mead, Joey Lou
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 126 leaves; 6502584 bytes; 6502339 bytes; application/pdf; application/pdf
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by Joey Lou Mead.; Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1986.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Bibliography: leaves 121-126.

‣ Crystal growth of KTiOPO₄ from high-temperature solution

Bordui, Peter Frank
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 120 leaves; 8513481 bytes; 8513241 bytes; application/pdf; application/pdf
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by Peter Frank Bordui.; Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1987.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Vita.; Bibliography: leaves 117-119.

‣ Multiscale mechanical studies of nacre from gastropod mollusk Trochus Nilocitus

Bruet, Benjamin J. F. (Benjamin Jean Fernand), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 83 p.; 4147986 bytes; 4156885 bytes; application/pdf; application/pdf
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(cont.) revealed jagged and branched crack fronts at plate interface, tortuous crack paths, non-uniform angles of polygons (suggesting possible intrinsic deformability and displacement/sliding). The technique of nanoindentation was carried out on individual aragonite tablets using a diamond-coated Berkovich probe tip (end-radius of 70 nm, tip angle of 142.3 degrees), at a rate of indentation of 10 [micro]N/s (load controlled), forces from 10 to 1000 [micro]N and indentation depths from 10 to 97 nm. AFM inspection of the indented region showed the existence of extensive plastic deformation within the tablet and suggested that occluded biomacromolecules may play a significant role in the deformation at loads below 100 [micro]N. Using the contact elastic theory, a Young modulus of 112.3 GPa and a hardness of 10.5 GPa were found for an individual platelet. This study shows that a biocomposite principally composed of a poor ceramic (aragonite) can achieve surprisingly good macroscopic mechanical properties thanks to a complex hierarchical structure allowing an extraordinary variety of energy-dissipating mechanisms. Our aim is to continue to formulate multiscale structure-property relationships to eventually aid in the design and advancement of new synthetic biologically inspired lightweight...

‣ Thermal-mechanical fatigue behavior of nickel-base superalloys

Marchand, Norman J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 2 v. (440 [i.e. 442] leaves); 17786848 bytes; 17847979 bytes; application/pdf; application/pdf
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by Norman J. Marchand.; Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1986.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Bibliography: leaves 185-199.

‣ Investigating the molecular origins of biocompatibility : intermolecular interactions between human serum albumin and various chemically modified surfaces via high resolution force spectroscopy

Rixman, Monica Anne, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 215 p.; 8567989 bytes; 8567796 bytes; application/pdf; application/pdf
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The first step in two of the most troublesome biological responses to the implantation of blood-contacting biomaterials, i.e. thrombosis and inflammation, is the adhesion of blood plasma proteins to the biomaterial surface, which may then initiate platelet adhesion and activation, and thereby set in motion a cascade of adverse host responses. If devices could be developed that prevent that first step from occurring altogether, a new generation of "stealth" biomaterials would be born. Such was the motivation of this project, which sought to investigate the constituent intermolecular interaction forces governing protein adhesion to biomaterials, using the technique of high resolution force spectroscopy. The model protein chosen for our study was human serum albumin (HSA), the smallest and most abundant blood protein in the human body, and typically the first to adsorb to a blood-contacting, implanted device. In the first stage of our investigation, HSA was covalently grafted to a nanosized probe tip at the end of a soft, microfabricated cantilever force transducer. The intermolecular interaction potential, U(D), was recorded between the HSA-modified probe tip and four different model surfaces, including: 1) gold, 2) a hydrophobic, CH3-terminated alkanethiol self-assembling monolayer (SAM)...

‣ Processing effects on the high cycle fatigue life of weld repaired cast Ti-6A1-4V parts

Hunter, Gordon Bruce
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 81 leaves; 5115840 bytes; 5119279 bytes; application/pdf; application/pdf
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by Gordon Bruce Hunter.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1981.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Includes bibliographical references.

‣ Effect of oxygen on creep crack growth in nickel-base superalloys

Bain, Kenneth Rees
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 195 leaves; 8446234 bytes; 8446049 bytes; application/pdf; application/pdf
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by Kenneth Rees Bain.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Includes bibliographical references.

‣ Mechanical characterization and in vivo operation of an implantable drug delivery MEMS device

Li, Yawen, 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 137 p.
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The goal of this thesis was to advance an implantable drug delivery MEMS (MicroElectroMechanical Systems) device developed in our laboratory. This device was designed to locally deliver multiple substances in complex release profiles in order to maximize the effectiveness of drug therapies. It consists of an array of microreservoirs etched into a silicon substrate. Different types and dosages of drugs can be contained in these reservoirs capped by thin gold membranes. The drug release is achieved by the application of a small anodic potential on the gold membrane in a chloride containing medium (such as the body fluid). The gold membrane will corrode and disintegrate so that the drug contained within the reservoir is free to diffuse into the surrounding medium. Previous researchers have demonstrated in vitro and in vivo release of tracer molecules as well as a radiolabled chemotherapeutic agent (carmustine, or BCNU) from the device. However, systematic characterization of the mechanical and electrochemical behavior of gold membranes on the drug delivery device was necessary in order to achieve more reliable device performance and to demonstrate efficacy of BCNU delivered from the MEMS device against an experimental tumor model. A bulge test apparatus was constructed to characterize the mechanical properties of gold membranes. Uniform pressure was applied from underneath the gold membrane and the membrane deflection was measured using optical interferometry. Analyzing the deflection and pressure data allowed extraction of the elastic modulus and residual stress of the gold membrane.; (cont.) Gold membranes with in-plane sizes ranging from 20 to 200pim showed lower modulus (126-168 GPa) than bulk (111) single crystal gold (189 GPa). But their yield strength (317-351 MPa) was higher than the bulk value. An in situ experimental setup was constructed to observe the electrochemical disintegration process of the gold membranes. Real time images recorded from a CCD camera showed non-uniform corrosion occurring first around the membrane edges. Bulge tests on the corroded membranes indicated a gradual loss of mechanical integrity of the gold membranes due to corrosion. The gold membrane disintegration probably occurred by a combination of membrane thinning through active dissolution and accumulation of plastic deformation due to the transient formation of a passive film on top of the gold membrane in each voltammetry cycle. Dense gold membranes with reproducible opening behavior are critical to the success of large scale in vivo studies and future commercial applications. Defects in the gold membranes led to premature leakage of BCNU...

‣ Wettability of low Sn solders on integrated circuit package metallizations

Gabriel, Michelle Wendy
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 73 leaves
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by Michelle Wendy Gabriel.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

‣ Adsorption and conformation change of short helical peptides on silica and aluminosilicate surfaces

Read, Michael J. (Michael Joseph), 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 206 p.; 9643176 bytes; 9642155 bytes; application/pdf; application/pdf
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Motivated by the challenges in understanding important features of protein adsorption, the interactions between (-helical peptides and a carefully selected set of model surfaces were studied. The peptide sequences contained three blocks of two to five residues each, with the side chains of the N-terminal and C-terminal blocks having negative and positive charges, respectively, and the central block having uncharged side chains. The conformation of a variety of such peptides was studied in solution by circular dichroism (CD) and H nuclear magnetic resonance (NMR) spectroscopy, in order to characterize the degree of xc-helicity in solution, as a function of temperature, pH, and chemical denaturant (urea) concentration. Intramolecular electrostatic interactions arising from the charged side chains, together with the central block of gc-helix-forming alanine residues, were found to stabilize oc-helicity. These interactions were balanced by the natural tendency toward disordered structures, which resulted in fractional oc-helicities between 25% and 50% when in solution. Adsorption isotherms for the peptide Ac-DDDDAAYAARRRR-Am on amorphous colloidal silica nanoparticles were studied in detail. A greater amount of peptide was adsorbed at basic pH than at neutral pH. The was fit with Langmuir and Frumkin isotherms...