Página 17 dos resultados de 3096 itens digitais encontrados em 0.069 segundos

‣ Templated aqueous synthesis of inorganics within carboxyl-containing block copolymer domains

Boontongkong, Yot
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 153 leaves; 56055862 bytes; 56055614 bytes; application/pdf; application/pdf
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Template-directed, aqueous-based syntheses of nanoscale inorganic materials in carboxyl-functionalized block copolymer domains (nanoreactors) were demonstrated. First, the successful application of electroless metal deposition within the sub-surface lamellar domains of an amphiphilic block copolymer is presented. Several electroless metals were selectively deposited inside the interconnected network of the water-permeable block domains containing pre-loaded palladium, which served as the spatially localized deposition catalyst. The technique proved to be a facile means to rapidly deposit large amounts of metals within the hydrophilic block domains, despite limitations on the transport of plating reagents into the bulk templates. The simple process yielded novel nanocomposites consisting of alternating layers of metal with those of the hydrocarbon matrix. The extent of metal deposition within the bulk block copolymer templates was controlled by adjusting the deposition rate and deposition time. Second, unique self-assembled thin film templates comprising in-plane arrays of nanosized surface cavities were investigated. The micellar thin films, formed by direct casting of kinetically stable styrene(PS)-acrylic acid(PAA) block copolymer reverse micelles from toluene onto solid substrates...

‣ Analysis of ultra-narrow ferromagnetic domain walls

Jenkins, Catherine A. (Catherine Ann), 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 71 p.; 2419937 bytes; 2419737 bytes; application/pdf; application/pdf
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A mathematical analysis of ultra-narrow ferromagnetic domain walls was undertaken, with graphical plots coded in the programming language TrueBASIC. An intrinsic inter-atomic potential stemming from the breakdown of the continuum approximation of matter is calculated and its contribution to the coercive force of hard materials is depicted. The interaction of a very narrow domain wall with a similarly narrow planar defect is analyzed. Time-dependent motion of such walls is modeled for various external driving forces and in different combinations of material parameters. This work was completed in parallel with a study of narrow crystallographic magnetic discontinuities known as twin boundaries, and was designed to gain an intuition into the control of high-anisotropy magnetic recording devices. The equations developed here would be particularly useful as a basis for approaching the calculations of the stability of high-density storage media.; by Catherine Jenkins.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2004.; Includes bibliographical references (p. 35).

‣ High index contrast platform for silicon photonics

Akiyama, Shoji, 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 206 p.; 12078490 bytes; 12104848 bytes; application/pdf; application/pdf
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This thesis focuses on silicon-based high index contrast (HIC) photonics. In addition to mature fiber optics or low index contrast (LIC) platform, which is often referred to as Planar Lightwave Cirrcuit (PLC) or Silica Optical Bench (SiOB), the use of HIC platform has been attracting considerable attention recently for the purpose of dense integration of optical components on chip. There are two ultimate solutions to mold of the flow of light. One is high index contrast HIC optics, where the index difference ([delta]n) of core and cladding is more than 0.5 and light is strongly confined in the core, which enables us to integrate optical circuits in m order. Another technique is the introduction of photonic crystal, with which the flow of light is controlled by its photonc bandgap (PBG) and the defect. The concept of photonic crystal can be applied to optical wavgeuides by placing the defect, which is surrounded with photonic crystal structures. In addition to wavgeuide applications, there are lots of unexplored attractive applications for photonic crystal, especially for high index contrast photonic crystal (HIC-PC or HIC-PBG), such as Si/SiO₂ or Si/Si₃N₄ materials systems, due to the wide stop-band. In this thesis, the various applications based on HIC-PBG platform are proposed and investigated. All of the works in this thesis are based on Silicon CMOS-compatible techniques for practical applications. In first three chapters (chapter 2...

‣ Investigation of short-range surface forces to develop self-organizing devices by Steven M. Tobias.

Tobias, Steven M., 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 69 leaves; 3964504 bytes; 3971298 bytes; application/pdf; application/pdf
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Force spectra from atomic force microscopy were used to verify surface energy components of indium tin oxide and mesocarbon microbeads. These materials were selected based on spectroscopic and thermodynamic parameters to be used in self-organizing devices. Estimates for surface energy were based on the van der Waals contribution described by Lifshitz theory and the polar contribution described by electron donor and acceptor components. This new type of device assembly process can be self-organizing based on the principle of like particle attraction and dissimilar particle repulsion. A thin insulting barrier could be inserted at the interface between two different types of particles, enabling junction formation. The criteria necessary to create a device based on surface energy components was specified.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.; Leaf 69 blank.; Includes bibliographical references (leaves 65-68).

‣ Anomalous solubility behavior of mixed monolayer protected metal nanoparticles

Myerson, Jacob W
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 32 leaves; 1399518 bytes; 1398494 bytes; application/pdf; application/pdf
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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.; Thesis (S.B.)--Massachusetts Institute of Technology...

‣ Evaluation of the commercial potential of novel organic photovoltaic technologies

Barr, Jonathan (Jonathan Allan)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 49 leaves; 2581086 bytes; 2583036 bytes; application/pdf; application/pdf
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Photovoltaic cells based on organic semiconducting materials have the potential to compete with the more mature crystalline and thin film based photovoltaic technologies in the future primarily due to the expectation of significantly reduced manufacturing costs. Stabilized power conversion efficiencies of organic photovoltaics are still well below those of crystalline Si photovoltaics, however a continuous, high throughput, roll-to-roll manufacturing process involving low temperature deposition or printing techniques is expected to partially account for their reduced efficiency and boost their commercial attractiveness. In addition, organic photovoltaics are flexible, light weight, and not fragile which makes them particularly suitable for transportation and portable electronics applications. Four organic photovoltaic technologies as well as the advantages and setbacks of each are described including Graetzel (wet) cells, blended photovoltaics, asymmetric tandem cells with hybrid planar-mixed molecular heterojunctions, and external antenna photovoltaics. A variety of start-up companies in various stages of commercialization of these technologies as well as the intellectual property related to these technologies is also discussed.; (cont.) A simplified cost model is presented to quantitatively estimate the possible cost reductions that continuous roll-to-roll production could entail for three different scenarios. Finally...

‣ Supramolecular nano-stamping : analyzing market potential

DePalma, Christina Maria
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 36 leaves; 1746221 bytes; 1747614 bytes; application/pdf; application/pdf
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An analysis was carried out on the process of Supramolecular Nano-Stamping (SuNS) in order to determine whether or not the science involved has market potential in the DNA microarray industry. This industry is rapidly expanding and succeeding in such an atmosphere would generate a large amount of revenue. Supramolecular Nano-Stamping provides a way to reproduce DNA microarrays at a significantly lower cost than current competitors who manufacture chips of a similar quality. The results indicate that Supramolecular Nano-Stamping has the potential to succeed in the DNA microarray industry. There are many factors which must first be examined before these conclusions can be reached, including analysis of current and potential competition, as well as the growth and development of the DNA microarray industry as a whole. This is done through a detailed intellectual property search and formation of a cost model and eventual business strategy.; by Christina Maria DePalma.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.; Includes bibliographical references (leaf 36).

‣ Incorporation of silica into baroplastic core-shell nanoparticles

Hewlett, Sheldon A
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 33 p.; 1356517 bytes; 1355580 bytes; application/pdf; application/pdf
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Core-shell baroplastics are nanophase materials that exhibit pressure-induced flow at low temperatures and high pressures. Core-shell baroplastics used in this work are comprised of a low Tg poly(butyl acrylate) (PBA) core and a high Tg polystyrene (PS) shell. These novel polymer systems can be molded into fully formed, 3-D shapes with the application of high pressure at room temperature. While the mechanical properties are equivalent to or better than those of commercial thermoplastic elastomers, more can be done to improve upon individual aspects of the mechanical properties, such as elastic modulus. This work looks at creating baroplastic nanocomposites with the goal of improving upon the mechanical properties. To accomplish this goal, two incorporation strategies for introducing silica nanoparticles were developed. The pre-emulsion strategy incorporated hydrophobized silica nanoparticles inside the core-shell nanoparticles to create core-shell-shell nanoparticles. The post-emulsion strategy incorporated charged silica nanoparticles after core-shell emulsion, with the intention of creating crystalline structures with silica and core-shell nanoparticles.; (cont.) The pre-emulsion strategy resulted in a decrease in particle size for the core-shell-shell nanoparticles...

‣ A study investigating copper smelting remains from San Bartolo, Chile

Alunni, Antonella I
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 145 leaves; 5848703 bytes; 5856692 bytes; application/pdf; application/pdf
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Introduction: Research on the metallurgy of archaeological artifacts has focused primarily on the examination of objects to reveal their design, their composition, the properties of the material people selected to achieve the design, and the fabrication processes used in managing the metal to produce the end product. Recently that focus has begun to broaden, and archaeologists are taking a step back to investigate the earliest stages of prehistoric metal processing that precede object manufacture, namely ore mining and extractive metallurgy. However, little archaeological work on mining and extraction has been accomplished to date, in part because so few metal processing sites have been identified. These sites are very difficult to find because of the lack of standing architecture, particularly smelting installations. Prehistoric smelting furnaces tend to be small and are either excavated beneath the ground surface or are above ground but made of impermanent materials.; by Antonella I. Alunni.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.; Includes bibliographical references (leaves 63-66).

‣ Carbon nanotube interconnects for IC chips; CNT interconnects for Integrated Chip chips

Anwar Ali, Hashina Parveen
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 97 leaves
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Carbon nanotubes (CNTs) have been investigated as candidate materials to replace or augment the existing copper-based technologies as interconnects for Integrated Circuit (IC) chips. Being ballistic conductors, CNTs are capable of carrying higher current densities of up to 10¹⁰A/cm² and high thermal conductivity. This thesis examines the technological aspect of carbon nanotubes - how these tubes can excel in place of copper in terms of their performance and integration into the current commercial IC chip process. A detailed literature review is covered, together with a performance analysis of the resistances between copper and CNT interconnects. Further, a business model is proposed on the possibility of introducing this technology into the mainstream IC industry.; by Hashina Parveen Anwar Ali.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.; Includes bibliographical references (leaves 93-94).

‣ Development of monolithic CMOS-compatible visible light emitting diode arrays on silicon; Development of monolithic complementary metal oxide semiconductor-compatible visible LED arrays on silicon

Chilukuri, Kamesh
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 103 p.
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The synergies associated with integrating Si-based CMOS ICs and III-V-material-based light-emitting devices are very exciting and such integration has been an active area of research and development for quite some time now. SiGe virtual substrate technology presents one way to integrate these materials. A more practical approach to monolithic integration based on the SiGe virtual substrate technology was followed in this work which involves wafer bonding and hydrogen-induced exfoliation to transfer a thin layer of device-quality silicon on top of the SiGe graded buffers to produce Silicon on Lattice Engineered Substrate (SOLES). SOLES wafers are suitable for the practical fabrication of SOI CMOS circuits and III-V-based photonic devices on a common silicon substrate. A novel monolithic CMOS compatible AlGaInP visible LED array on the SOLES platform was developed, fabricated and demonstrated in this work. The prototype array is an important breakthrough in the realization of the ultimate objective - monolithically integrated optical interconnects in high speed digital systems.; by Kamesh Chilukuri.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.; Includes bibliographical references (p. 102-103).

‣ Acoustic assisted actuation of Ni-Mn-Ga ferromagnetic shape memory alloys

Peterson, Bradley William
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 115 p.
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Ferromagnetic shape memory alloys (FSMA) have been shown in recent work to exhibit large magnetic field induced strains. The material generally requires a large threshold field (of order 3-4 kOe) to initiate the strain. Thus, the power requirements are large and actuators based on these materials could tend to be large. This thesis reports on the effect on the actuation properties of Ni-Mn-Ga single crystals of the use of a sinusoidal stress wave generated by a piezoelectric stack actuator. The piezoelectric drive causes a time varying stress wave in the FSMA that resolves as a shear across the twin-boundaries and aids the twin boundary in overcoming defect-related obstacles. The FSMA shows increased strain and a reduction in threshold field. The effect is most pronounced for crystals showing large initial threshold fields which are associated with high defect strengths or concentrations. For crystals with a large threshold, 4.7 kOe, actuated at 1 Hz, the piezoelectric drive reduces the threshold field by as much as 21% for a piezoelectric driven at 5 kHz and 20 Vrms. As a result of this large threshold reduction, strain output can be more than doubled for magnetic drive amplitudes near the threshold field.; (cont.) Strain improvement is modest...

‣ Commercialization potential of compositionally graded Ge - Si₁₋x̳Gex̳ - Si substrates for solar applications

Goh, Johnathan Jian Ming
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 103 leaves
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This project considers the potential of Ge - Si₁₋x̳Gex̳ - Si substrates for solar applications. The use of compositionally graded substrates to achieve heterointegration across different materials platforms such as Si, Ge and GaAs has proven successful and dual junction solar cells have been fabricated on such substrates. The potential for graded substrates in the solar market is discussed considering the current technology, market players and worldwide renewable energy policies. A cost model is also developed and analyzed in the course of writing to assess the feasibility of this commercial enterprise. The result of these analyses highlights the technical and commercial viability of graded substrates in the solar market.; by Johnathan Jian Ming Goh.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.; In title on t.p., double-underscored "x" appears as subscript.; Includes bibliographical references.

‣ Evaluation of on-chip integration of magneto-optic isolators

Chen, Xiaoyan, M. Eng. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 62 leaves
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The recent development of on chip integration of magneto-optic isolators is reviewed. Two major categories of structural designs for waveguide isolator (nonreciprocal mode conversion and nonreciprocal phase shift) have both merits and short comings for integration. The advances in integration techniques and materials related developments in the last decade are a big step towards monolithic integration of isolator with other optical devices. But whether or not the integrated magneto-optic isolators will penetrate the market eventually would also depend not its competing technologies.; by Xiaoyan Chen.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.; Includes bibliographical references (leaves 57-62).

‣ Field induced switching in multilayer rhombic magnetic rings

Pacella, James N
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 28 leaves
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Multilayer rhombic magnetic rings are researched as a structure for the "pseudo spin valve" device that could possibly become useful in magnetic materials applications such as MRAM, digital logic, and sensors through the use of multiple resistance states exhibited within these devices. The magnetization reversal characteristics of these structures are explored in an effort to fully understand interactions occurring within the devices and their resulting effect on giant magnetoresistance (GMR). Contact configuration and angular dependence of applied field are also examined. Using submicron thickness rhombic rings with long axis dimension -1.5gjm, major loop magnetization sweeps were conducted, as well as minor loops in order to excite several resistance states within the devices. It was found from major loop applied field sweeps that rhombic multilayer rings exhibit five stable magnetoresistive states, with an additional state excited through execution of a minor loop field sweep. In addition, using the contact configurations known as "classical" and "wheatstone bridge" provide additional information on interactions that are occurring within the structures. It was found that both contact configurations were sensitive to similar changes in the devices...

‣ Design of a CMOS compatible, athermal, optical waveguide; Design of a complementary metal oxide semiconductor compatible, athermal, optical waveguide

Fernandez, Luis Enrique, S.B. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 49 p.
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This paper explores a possible design for a CMOS compatible, athermal, optical waveguide. The design explored is a slot waveguide with light guided in the low index material. A design paradigm is proposed which shows the relationship between cross-sectional parameters and their impact on both the effective index of refraction and the thermo-optic coefficient of the device. Two materials choices were explored to serve as the low index material, poly(ether imide) (PI) and poly(methyl methacrylate) (PMMA). The slot waveguide with PI as the low index material had a simulated, device thermo-optic coefficient of -8.5 x 10-4K-1, and the slot waveguide with PMMA as the low index material had a simulated, device thermo-optic coefficient of 1.7 x 10-5K-1.; by Luis Enrique Fernandez.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.; Includes bibliographical references (p. 49).

‣ A conjugated polymer plastic gel

Alcazar Jorba, Daniel
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 119 p.
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We present a gel route to process highly oriented conjugated polymer films and fibers. The incorporation of hexafluoroisopropanol, a strong and stable dipolar group, to the polythiophene backbone enhances the solubility and especially, the hydrogen bond forming capabilities of the polymer. This functionalization enables the polymer to build up an isotropic self-supporting network structure based on a combination of polymer-polymer chain interactions and interchain hydrogenbondings. These thermally reversible physical crosslinks incorporate plasticity in the conjugated polymer gel. The gel network can be melted and then transformed via mechanical deformation to form an anisotropic gel with the chains highly aligned along the tensile direction. The oriented gel morphology comprises a distribution of crystalline clusters in an overall swollen network. In these ordered regions, conjugated backbones are [pi]-stacked with respect to each other neighbors. The mechanically induced structural rearrangement from an isotropic to an anisotropic conjugated polymer gel occurs when transitioning from the molten state to the gel state. This study highlights the versatility of incorporating plasticity in the design of conjugated polymer materials via a gel processing technology and its potential for applications.; by Daniel Alcazar Jorba.; Includes bibliographical references (p. 107-119).; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ Economic potential of high density data storage implemented by patterned magnetic media technology

Du, Lei, M. Eng. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 65 leaves
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Hard drive industry is facing scaling challenge for areal density to be further increased. This is due to the triangular conflictions among thermal stability (superparamagnetic effect), single-to-noise ratio and writability of the recording media. One of the most promising methods to overcome this constraint is the patterned magnetic media technology. Although it is facing many challenges, the large potential gains in density offered by patterned media make it one of the possible milestones on the horizon for future of the disk drives industry. One of the biggest challenges for patterned media is to realize its mass fabrication provided reduced cost per bit. The basic fabrication approach is to use lithography to pattern the magnetic materials on the platter. However, patterned media requires well-ordered nanoarrays with dimensions less than 25 nm, which challenges the state-of-art lithography technologies. This M. Eng. project focuses on evaluations of the technologies and fabrication schemes potential for patterned media from various aspects like technical barriers, cost and intellectual properties. Technologies including E-beam lithography, nanoimprint lithography, templated diblock copolymer self-assembly and self-assembled magnetic nanoparticles are discussed. Cost modeling was done to prove the enormous gain in revenue for the proposed fabrication scheme. It is proposed that the fabrication scheme of templated diblock copolymer for making the master stamp for nanoimprint followed by nanoimprint lithography for mass production has the largest potential for patterned media. However...

‣ Pulse-field actuation of collinear magnetic single crystals

Jenkins, Catherine A. (Catherine Ann), 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 34 p.; 1177750 bytes; 1176987 bytes; application/pdf; application/pdf
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Ferromagnetic shape memory alloys (FSMAs) are a class of alloys that exhibits the shape memory effect, as in the alloy nickel-titanium, sometimes known as Nitinol. In FSMAs, though, the shape changes are not brought on just by changes in temperature or mechanical stresses, but can also be driven by the application of a relatively small magnetic field. The large strains exhibited by such materials are a result of the coexistence of several features, including a thermoelastic martensitic transition, and a ferromagnetic martensite (non-equilibrium, low-temperature) phase. The magnetocrystalline anisotropy must also be large, as seen in similar alloys such as iron-palladium (Fe₇₀Pd₃₀) [1]. Nickel-manganese-gallium is an FSMA that has shown up to 10% strain in certain orientations as an effect of unconstrained magnetic actuation [4]. To achieve cyclic actuation in FSMAs, the field-induced extension has conventionally been reversed by a compressive mechanical stress from a spring or field orthogonal to the actuating field. The use of a second FSMA crystal to provide the reset force was unreported. Collinear single crystals are shown here to be able to induce a 2.8% reset strain against one another when subjected alternately to individual pulsed magnetic fields in a custom designed and constructed apparatus. A setup of this type could be used in a bistable microswitch...

‣ A market analysis for high efficiency multi-junction solar cells grown on SiGe

Judkins, Zachara Steele
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 53 leaves
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Applications, markets and a cost model are presented for III-V multi-junction solar cells built on compositionally graded SiGe buffer layers currently being developed by professors Steven Ringell of Ohio State University and Eugene Fitzgerald of MIT. Potential markets are similar to those currently occupied by high efficiency multi-junction space solar cells grown on a Germanium substrate. Initial cost analysis shows that at production volumes similar to those of the state of the art, cost could be reduced by a factor of' four. Significant market share may be gained in both the space and terrestrial PV markets due to improved performance associated with superior materials properties advantages as well as production cost reductions.; by Zachary Steele Judkins.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.; Includes bibliographical references (leaves 50-53).