Open Access. Powered by Scholars. Published by Universities.®

Materials Science and Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Michigan Technological University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 211 - 240 of 318

Full-Text Articles in Materials Science and Engineering

3-D Printing Open-Source Click-Muac Bands For Identification Of Malnutrition, Ross Michaels, Joshua M. Pearce May 2017

3-D Printing Open-Source Click-Muac Bands For Identification Of Malnutrition, Ross Michaels, Joshua M. Pearce

Department of Materials Science and Engineering Publications

No abstract provided.


Gradient-Enriched Finite Element Methodology For Axisymmetric Problems, C. Bagni, H. Askes, E. C. Aifantis Apr 2017

Gradient-Enriched Finite Element Methodology For Axisymmetric Problems, C. Bagni, H. Askes, E. C. Aifantis

Michigan Tech Publications, Part 1

Due to the axisymmetric nature of many engineering problems, bi-dimensional axisymmetric finite elements play an important role in the numerical analysis of structures, as well as advanced technology micro/nano-components and devices (nano-tubes, nano-wires, micro-/nano-pillars, micro-electrodes). In this paper, a straightforward C0-continuous gradient-enriched finite element methodology is proposed for the solution of axisymmetric geometries, including both axisymmetric and non-axisymmetric loads. Considerations about the best integration rules and an exhaustive convergence study are also provided along with guidances on optimal element size. Moreover, by applying the present methodology to cylindrical bars characterised by a circumferential sharp crack, the ability of the present …


Emerging Business Models For Open Source Hardware, Joshua M. Pearce Mar 2017

Emerging Business Models For Open Source Hardware, Joshua M. Pearce

Department of Materials Science and Engineering Publications

The rise of Free and Open Source models for software development has catalyzed the growth of Free and Open Source hardware (also known as “Libre Hardware”). Libre Hardware is gaining significant traction in the scientific hardware community, where there is evidence that open development creates both technically superior and far less expensive scientific equipment than proprietary models. In this article, the evidence is reviewed and a collection of examples of business models is developed to service scientists who have the option to manufacture their own equipment using Open Source designs. Profitable Libre Hardware business models are reviewed, which includes kit, …


Emergence Of Home Manufacturing In The Developed World: Return On Investment For Open-Source 3-D Printers., Emily E. Petersen, Joshua M. Pearce Feb 2017

Emergence Of Home Manufacturing In The Developed World: Return On Investment For Open-Source 3-D Printers., Emily E. Petersen, Joshua M. Pearce

Department of Materials Science and Engineering Publications

Through reduced 3-D printer cost, increased usability, and greater material selection, additive manufacturing has transitioned from business manufacturing to the average prosumer. This study serves as a representative model for the potential future of 3-D printing in the average American household by employing a printer operator who was relatively unfamiliar with 3-D printing and the 3-D design files of common items normally purchased by the average consumer. Twenty-six items were printed in thermoplastic and a cost analysis was performed through comparison to comparable, commercially available products at a low and high price range. When compared to the low-cost items, investment …


Open-Source Automated Mapping Four-Point Probe, Handy Chandra, Spencer W. Allen, Shane W. Oberloier, Nupur Bihari, Jephias Gwamuri, Joshua M. Pearce Jan 2017

Open-Source Automated Mapping Four-Point Probe, Handy Chandra, Spencer W. Allen, Shane W. Oberloier, Nupur Bihari, Jephias Gwamuri, Joshua M. Pearce

Department of Materials Science and Engineering Publications

Scientists have begun using self-replicating rapid prototyper (RepRap) 3-D printers to manufacture open source digital designs of scientific equipment. This approach is refined here to develop a novel instrument capable of performing automated large-area four-point probe measurements. The designs for conversion of a RepRap 3-D printer to a 2-D open source four-point probe (OS4PP) measurement device are detailed for the mechanical and electrical systems. Free and open source software and firmware are developed to operate the tool. The OS4PP was validated against a wide range of discrete resistors and indium tin oxide (ITO) samples of different thicknesses both pre- and …


Electrospinning Novel Aligned Polymer Fiber Structures For Use In Neural Tissue Engineering, Rachel Martin Jan 2017

Electrospinning Novel Aligned Polymer Fiber Structures For Use In Neural Tissue Engineering, Rachel Martin

Dissertations, Master's Theses and Master's Reports

A suitable tissue scaffold to support and assist in the repair of damaged tissues or cells is important for success in clinical trials and for injury recovery. Electrospinning can create a variety of polymer nanofibers and microfibers, and is being widely used to produce experimental tissue scaffolds for neural applications. This dissertation examines various approaches by which electrospinning is being used for neural tissue engineering applications for the repair of injuries to the central nervous system (CNS) and the peripheral nervous system (PNS). Due to the poor regeneration of neural tissues in the event of injury, tissue scaffolds are being …


Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li Jan 2017

Nonlinear Dielectric Behavior Of Field-Induced Antiferroelectric/Paraelectric-To-Ferroelectric Phase Transition For High Energy Density Capacitor Application, Mingyang Li

Dissertations, Master's Theses and Master's Reports

Electric field-induced antiferroelectric(AFE)/paraelectric(PE)-to-ferroelectric(FE) phase transitions are investigated for the associated nonlinear dielectric behavior, which could offer high dielectric capacity. The phenomenon in monolithic materials has been computed for Kittel antiferroelectric and BaTiO3 model systems using the Landau-Ginzburg-Devonshire theory. The general switching curves give values of the polarization as a function of external electric field. A similar computation is performed for particle-filled polymer-matrix composites where an internal depolarization field is considered. The polarization-electric field response changes with different depolarization factors, which demonstrate the shape and alignment of the dielectric particles embedded in polymer-matrix are key factors for the composite to …


Utilizing Reprap Style 3d Printers For The Manufacturing Of Composite Heat Exchangers, John Laureto Jan 2017

Utilizing Reprap Style 3d Printers For The Manufacturing Of Composite Heat Exchangers, John Laureto

Dissertations, Master's Theses and Master's Reports

The low cost 3D printing market is currently dominated by the application of RepRap (self-replicating rapid-prototyper) variants. Presented in this document are practical utilizations of RepRap technology. Developed are innovative processes to manufacture composite materials systems for thermal management solutions.

First, a laser polymer welder system is validated by quantifying maximum peak load and weld width of linear low density polyethylene (LLDPE) lap welds as a function of linear energy density. The development of practical engineering data, in this application, is critical to producing mechanically durable welds. Developed laser and printer parameter sets allow for manufacturing of LLDPE multi-layered heat …


Design Of Robust Hydrogel Based On Mussel-Inspired Chemistry, Yuan Liu Jan 2017

Design Of Robust Hydrogel Based On Mussel-Inspired Chemistry, Yuan Liu

Dissertations, Master's Theses and Master's Reports

The structure of catechol is found in mussel adhesive proteins and contributed to both wet-resistant adhesion and cohesive curing of these proteins. A synthetic nano-silicate, Laponite was incorporated into catechol-containing hydrogels and the hydrogel network-bound catechol formed strong reversible interfacial interaction with Laponite. The contribution of incorporated catechol-Laponite reversible interfacial interactions to the mechanics of hydrogels constructed by different strategies was studied. In the first strategy, Laponite and catechol were introduced into the double network hydrogel (DN) via the free radical co-polymerization of a catechol-containing monomer, backbone monomer, and crosslinker. The introduction of catechol-Laponite interactions significantly improved the compressive strength …


A 3d Biomimetic Scaffold Using Electrospinning For Tissue Engineering Applications, Samerender Nagam Hanumantharao Jan 2017

A 3d Biomimetic Scaffold Using Electrospinning For Tissue Engineering Applications, Samerender Nagam Hanumantharao

Dissertations, Master's Theses and Master's Reports

Electrospinning holds great promise for designing functional 3D biomimetic scaffolds for tissue engineering applications. The technique allows for the reproducible fabrication of 3D scaffolds with control over the porosity and thickness. In this work, a novel method for the synthesis of a 3D electroactive scaffold using electrospinning from polycaprolactone (PCL), Polyvinylidene Fluoride (PVDF) and Polyaniline (PANI) is reported. Additional scaffolds involving different morphologies of PCL, PCL-PVDF and PCL-PANI-PVDF were also fabricated and evaluated. The scaffolds were characterized using electron microscopy to visualize the morphologies. Infrared spectroscopy was used to confirm the presence of polymers and their respective phases in the …


Evaluation Of Thermal Stability Of Ausferrite In Austempered Ductile Iron Using Differential Scanning Calorimetry, Karl Warsinski Jan 2017

Evaluation Of Thermal Stability Of Ausferrite In Austempered Ductile Iron Using Differential Scanning Calorimetry, Karl Warsinski

Dissertations, Master's Theses and Master's Reports

Austempered Ductile Iron (ADI) is prone to changes in microstructure and mechanical properties when exposed to elevated service temperatures. Differential Scanning Calorimetry has been used to evaluate the stabilizing effects of copper, nickel, molybdenum, and cobalt on the ausferrite structure. Previous studies have conflated the effects of various alloy additions, and little effort has been made to systematically catalog the effects of individual elements. The focus of the current research has been to identify alloying elements that more strongly stabilize the ausferrite structure in order to improve service life of ADI at elevated temperatures. Nickel has been shown to have …


Structural Characteristics And Corrosion Behavior Of Bio-Degradable Zn-Li Alloys In Stent Application, Shan Zhao Jan 2017

Structural Characteristics And Corrosion Behavior Of Bio-Degradable Zn-Li Alloys In Stent Application, Shan Zhao

Dissertations, Master's Theses and Master's Reports

Zinc has begun to be studied as a bio-degradable material in recent years due to its excellent corrosion rate and optimal biocompatibility. Unfortunately, pure Zn’s intrinsic ultimate tensile strength (UTS; below 120 MPa) is lower than the benchmark (about 300 MPa) for cardiovascular stent materials, raising concerns about sufficient strength to support the blood vessel. Thus, modifying pure Zn to improve its mechanical properties is an important research topic.

In this dissertation project, a new Zn-Li alloy has been developed to retain the outstanding corrosion behavior from Zn while improving the mechanical characteristics and uniform biodegradation once it is implanted …


Molecular Modeling Of Aerospace Polymer Matrices Including Carbon Nanotube-Enhanced Epoxy, Matthew Radue Jan 2017

Molecular Modeling Of Aerospace Polymer Matrices Including Carbon Nanotube-Enhanced Epoxy, Matthew Radue

Dissertations, Master's Theses and Master's Reports

Carbon fiber (CF) composites are increasingly replacing metals used in major structural parts of aircraft, spacecraft, and automobiles. The current limitations of carbon fiber composites are addressed through computational material design by modeling the salient aerospace matrix materials. Molecular Dynamics (MD) models of epoxies with and without carbon nanotube (CNT) reinforcement and models of pure bismaleimides (BMIs) were developed to elucidate structure-property relationships for improved selection and tailoring of matrices.

The influence of monomer functionality on the mechanical properties of epoxies is studied using the Reax Force Field (ReaxFF). From deformation simulations, the Young’s modulus, yield point, and Poisson’s ratio …


Multiscale Modeling: Thermal Conductivity Of Graphene/Cycloaliphatic Epoxy Composites, Sorayot Chinkanjanarot Jan 2017

Multiscale Modeling: Thermal Conductivity Of Graphene/Cycloaliphatic Epoxy Composites, Sorayot Chinkanjanarot

Dissertations, Master's Theses and Master's Reports

The thermal property of epoxy as the binder in the Carbon Fiber (CF) composites, especially thermal conductivity is important to achieve the advance technology and to improve the performance of materials. Multiscale modeling including molecular dynamic (MD) modeling and micromechanical modeling is used to study the properties of neat Cycloaliphatic Epoxies (CE) and Graphene nanoplatelet (GNP)/CE with and without covalent functionalization.

The thermal properties (glass-transition temperature, thermal expansion coefficient, and thermal conductivity) and mechanical properties of CE system are investigated by MD modeling using OPLS-All Atom force field. A unique crosslinking technique is developed to achieve the cured CE models …


Polyvinyl Alcohol (Pva) Fiber-Reinforced Rubber Concrete And Rubberized Self-Compacting Concrete, Jiaqing Wang Jan 2017

Polyvinyl Alcohol (Pva) Fiber-Reinforced Rubber Concrete And Rubberized Self-Compacting Concrete, Jiaqing Wang

Dissertations, Master's Theses and Master's Reports

This study experimentally investigates the mechanical performance and durability of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete and the rubberized self-compacting concrete. The waste rubber particles were introduced as a partial replacement of fine aggregate in the plain concrete. In addition, the waste tire rubbers were pre-treated with alkali surface treatment method to enhance the performance. The PVA fibers were added to the concrete mixes to enhance the post-failure resistance and thus fracture energy. Rubberized fiber concrete samples were prepared with different fine aggregate replacement ratios and the optimum fiber content. At the same time, the rubber particles had been used …


Microstructural Evolution And Mechanical Properties Of Zn-Ti Alloys For Biodegradable Stent Applications, Zhiyong Yin Jan 2017

Microstructural Evolution And Mechanical Properties Of Zn-Ti Alloys For Biodegradable Stent Applications, Zhiyong Yin

Dissertations, Master's Theses and Master's Reports

Stents made of biodegradable metallic materials are increasingly gaining interest within the biomaterials field because of their superior mechanical properties and biodegradation rates as compared to polymeric materials. Zinc and its alloys have been developed and investigated as possible candidates for biodegradable stent applications in the last five years. This study intended to formulate and characterize a new series of Zn-Ti alloys, with titanium additions of less than 1-3 wt%, with the primary objective to develop and select an alloy that meets benchmark values of mechanical properties for biodegradable stents. A series of Zn-Ti alloys was formulated through vacuum induction …


Formulation And Testing Of Biodegradable Polymeric Coating On Zinc Wires In Cardiovascular Stent Application, Avishan Arab Shomali Jan 2017

Formulation And Testing Of Biodegradable Polymeric Coating On Zinc Wires In Cardiovascular Stent Application, Avishan Arab Shomali

Dissertations, Master's Theses and Master's Reports

Biodegradable and biocompatible poly (L-lactic-acid) (PLLA) coating was applied on a modified zinc (Zn) substrate by dip coating, with the intent to delay the bio-corrosion and slow the degradation rate of zinc substrate. 3-(Trimethoxysilyl) propyl methacrylate (MPS) was used for modification of the zinc substrate for promoting the adhesion between the metallic substrate and the polymer coating. It is hypothesized that the delay in Zn biodegradation could be useful in the first several weeks to prevent the early loss of mechanical integrity of the endovascular stent and to improve the healing process of the diseased vascular site. The PLLA coating …


Tightening The Loop On The Circular Economy: Distributed Plastic Recycling With An Open Source Recyclebot, Shan Zhong Jan 2017

Tightening The Loop On The Circular Economy: Distributed Plastic Recycling With An Open Source Recyclebot, Shan Zhong

Dissertations, Master's Theses and Master's Reports

Following the goals of a circular economy, the growth of both plastic consumption and prosumer 3-D printing are driving an interest in producing 3-D printer filament from waste plastic. However, traditional recycling can have a significant environmental impact as it demands the collection and transportation of relatively low-density waste plastics to collection centers and reclamation facilities for separation and reconstruction. Compared to the traditional recycling, distributed recycling (where consumers directly recycle their own waste) has the potential to reduce energy consumption because it can save the energy for transportation needed in conventional recycling. A promising method of such distributed plastic …


Electro-Optic Contact Poling Of Polymer Waveguide Devices And Thin Films, Michael Briseno Jan 2017

Electro-Optic Contact Poling Of Polymer Waveguide Devices And Thin Films, Michael Briseno

Dissertations, Master's Theses and Master's Reports

Optical communication is a high speed, large bandwidth, low cost, and power efficient method of transferring data over short-haul and long-haul channels. Optical communication requires devices (optical modulators) that utilize the originating electrical signal information to modulate a corresponding optical signal. State of the art optical modulators can be used for communicating signals at modulation frequencies up to 100 GHz and faster. Polymer modulators are used over lithium niobate due to the large potential electro-optic coefficient, which has been shown to be as high as 226 pm/V in thin films.

Organic electro-optic polymers used in thin film modulators contain nonlinear …


Controlling Properties Of Agglomerates For Chemical Processes, Joseph A. Halt Jan 2017

Controlling Properties Of Agglomerates For Chemical Processes, Joseph A. Halt

Dissertations, Master's Theses and Master's Reports

Iron ore pellets are hard spheres made from powdered ore and binders. Pellets are used to make iron, mainly in blast furnaces. Around the time that the pelletizing process was developed, starch was proposed as a binder because it’s viscous, adheres well to iron oxides, does not contaminate pellets and is relatively cheap. In practice, however, starch leads to weak pellets with rough surfaces – these increase the amount of dust generated within process equipment and during pellet shipping and handling. Thus, even though the usual binder (bentonite clay) contaminates pellets, pelletizers prefer it to starch or other organics.

This …


Mse Annual Report 2017, Department Of Materials Science And Engineering, Michigan Technological University Jan 2017

Mse Annual Report 2017, Department Of Materials Science And Engineering, Michigan Technological University

Department of Materials Science and Engineering Annual Reports

Table of Contents

  • Faculty and Staff News
  • Faculty Research
  • Student News
  • Senior Design Teams
  • Graduate Student News
  • Outreach
  • Alumni News
  • By the Numbers
  • Scholarships


Rapid Metal Design, Paul G. Sanders Nov 2016

Rapid Metal Design, Paul G. Sanders

TechTalks

Computational material design tools have advanced so that custom materials for specific applications can be designed and manufactured. In the case of metals, my team designs aluminum, iron, nickel, and copper (more to come) alloys using Thermo-Calc with Bayesian optimization. We design microstructures to deliver properties such as strength, conductivity, and corrosion resistance. Custom tailored materials are now practical solutions to engineering challenges, and materials engineers work on multi-disciplinary teams to deliver integrated, enhanced product designs.


Open Source Database And Website To Provide Free And Open Access To Inactive U.S. Patents In The Public Domain, Yuenyong Nilsiam, Joshua M. Pearce Nov 2016

Open Source Database And Website To Provide Free And Open Access To Inactive U.S. Patents In The Public Domain, Yuenyong Nilsiam, Joshua M. Pearce

Department of Materials Science and Engineering Publications

Although theoretically the patent system is meant to bolster innovation, the current United States Patent and Trademark Office (USPTO) is cumbersome and involves a significant time investment to locate inactive patents less than 20 years old. This article reports on the development of an open source database to find these public domain ideas. First, a search strategy is explained. Then the operation and use of free and open source software are detailed to meet the needs of open hardware innovators. Finally, a case study is presented to demonstrate the utility of the approach with 3-D printing. The results showed how …


Mos2 As A Co-Catalyst For Photocatalytic Hydrogen Production From Water, Bing Han, Yun Hang Hu Nov 2016

Mos2 As A Co-Catalyst For Photocatalytic Hydrogen Production From Water, Bing Han, Yun Hang Hu

Michigan Tech Publications, Part 1

Solar-to-hydrogen conversion based on photocatalytic water splitting is a promising pathway for sustainable hydrogen production. The photocatalytic process requires highly active, inexpensive, and earth-abundant materials as photocatalysts. As a presentative layer-structured transition metal dichalcogenides, molybdenum disulfide (MoS2) is attracting intensive attention due to its unique electro and photo properties. In this article, we comprehensively review the recent research efforts of exploring MoS2 as a co-catalyst for photocatalytic hydrogen production from water, with emphasis on its combination with CdS, CdSe, graphene, carbon nitride, TiO2, and others. It is shown that MoS2–semiconductor composites are promising photocatalysts for hydrogen evolution from water under …


Lengthscale Effects On Exchange Coupling In Co-Pt L10 + L12 Nanochessboards, Eric P. Vetter, Liwei D. Geng, Priya Ghatwai, Dustin A. Gilbert, Yongmei M. Jin, William A. Soffa, Jerrold A. Floro Sep 2016

Lengthscale Effects On Exchange Coupling In Co-Pt L10 + L12 Nanochessboards, Eric P. Vetter, Liwei D. Geng, Priya Ghatwai, Dustin A. Gilbert, Yongmei M. Jin, William A. Soffa, Jerrold A. Floro

Michigan Tech Publications, Part 1

The Co-Pt nanochessboard is a quasi-periodic, nanocomposite tiling of L10 and L12 magnetic phases that offers a novel structure for the investigation of exchange coupling, relevant to permanent magnet applications. Periodicity of the tiling is controlled by the rate of cooling through the eutectoid isotherm, resulting in control over the L10-L12 exchange coupling. First order reversal curve analysis reveals a transition from partial coupling to nearly complete exchange-coupling in a Co40.2Pt59.8 nanochessboard structured alloy as the periodicity is reduced below the critical correlation length. Micromagnetic simulations give insights into how exchange coupling manifests in the tiling, and its impact on …


Open Source Laser Polymer Welding System: Design And Characterization Of Linear Low-Density Polyethylene Multilayer Welds, John Laureto, Serguei V. Dessiatoun, Michael M. Ohadi, Joshua M. Pearce Jul 2016

Open Source Laser Polymer Welding System: Design And Characterization Of Linear Low-Density Polyethylene Multilayer Welds, John Laureto, Serguei V. Dessiatoun, Michael M. Ohadi, Joshua M. Pearce

Department of Materials Science and Engineering Publications

The use of lasers to weld polymer sheets provides a means of highly-adaptive and custom additive manufacturing for a wide array of industrial, medical, and end user/consumer applications. This paper provides an open source design for a laser polymer welding system, which can be fabricated with low-cost fused filament fabrication and off-the-shelf mechanical and electrical parts. The system is controlled with free and open source software and firmware. The operation of the machine is validated and the performance of the system is quantified for the mechanical properties (peak load) and weld width of linear low density polyethylene (LLDPE) lap welds …


Free And Open-Source Control Software For 3-D Motion And Processing, Bas Wijnen, G. C. Anzalone, Amberlee S. Haselhuhn, Paul G. Sanders, Joshua M. Pearce Jan 2016

Free And Open-Source Control Software For 3-D Motion And Processing, Bas Wijnen, G. C. Anzalone, Amberlee S. Haselhuhn, Paul G. Sanders, Joshua M. Pearce

Department of Materials Science and Engineering Publications

RepRap 3-D printers and their derivatives using conventional firmware are limited by: 1) requiring technical knowledge, 2) poor resilience with unreliable hardware, and 3) poor integration in complicated systems. In this paper, a new control system called Franklin, for CNC machines in general and 3-D printers specifically, is presented that enables web-based three dimensional control of additive, subtractive and analytical tools from any Internet connected device. Franklin can be set up and controlled entirely from a web interface; it uses a custom protocol which allows it to continue printing when the connection is temporarily lost, and allows communication with scripts.


Influence Of Oxygen Concentration On The Performance Of Ultra-Thin Rf Magnetron Sputter Deposited Indium Tin Oxide Films As A Top Electrode For Photovoltaic Devices, Jephias Gwamuri, Murugesan Marikkannan, J. Mayandi, Patrick Bowen, Joshua M. Pearce Jan 2016

Influence Of Oxygen Concentration On The Performance Of Ultra-Thin Rf Magnetron Sputter Deposited Indium Tin Oxide Films As A Top Electrode For Photovoltaic Devices, Jephias Gwamuri, Murugesan Marikkannan, J. Mayandi, Patrick Bowen, Joshua M. Pearce

Department of Materials Science and Engineering Publications

The opportunity for substantial efficiency enhancements of thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic (PV) cells using plasmonic absorbers requires ultra-thin transparent conducting oxide top electrodes with low resistivity and high transmittances in the visible range of the electromagnetic spectrum. Fabricating ultra-thin indium tin oxide (ITO) films (sub-50 nm) using conventional methods has presented a number of challenges; however, a novel method involving chemical shaving of thicker (greater than 80 nm) RF sputter deposited high-quality ITO films has been demonstrated. This study investigates the effect of oxygen concentration on the etch rates of RF sputter deposited ITO films to …


High-Efficiency Solar-Powered 3-D Printers For Sustainable Development, Jephias Gwamuri, Dhiogo Franco, Khalid Khan, Lucia Gauchia, Joshua M. Pearce Jan 2016

High-Efficiency Solar-Powered 3-D Printers For Sustainable Development, Jephias Gwamuri, Dhiogo Franco, Khalid Khan, Lucia Gauchia, Joshua M. Pearce

Michigan Tech Publications, Part 1

The release of the open source 3-D printer known as the RepRap (a self-Replicating Rapid prototyper) resulted in the potential for distributed manufacturing of products for significantly lower costs than conventional manufacturing. This development, coupled with open source-appropriate technology (OSAT), has enabled the opportunity for 3-D printers to be used for sustainable development. In this context, OSAT provides the opportunity to modify and improve the physical designs of their printers and desired digitally-shared objects. However, these 3-D printers require electricity while more than a billion people still lack electricity. To enable the utilization of RepRaps in off-grid communities, solar photovoltaic …


Increasing Solar Energy Conversion Efficiency In Hydrogenated Amorphous Silicon Photovoltaic Devices With Plasmonic Perfect Meta – Absorbers, Jephias Gwamuri Jan 2016

Increasing Solar Energy Conversion Efficiency In Hydrogenated Amorphous Silicon Photovoltaic Devices With Plasmonic Perfect Meta – Absorbers, Jephias Gwamuri

Dissertations, Master's Theses and Master's Reports

Solar photovoltaic (PV) devices are an established, technically-viable and sustainable solution to society’s energy needs, however, in order to reach mass deployment at the terawatt scale, further decreases in the levelized cost of electricity from solar are needed. This can be accomplished with thin-film PV technologies by increasing the conversion efficiency using sophisticated light management methods. This ensures absorption of the entire solar spectrum, while reducing semiconductor absorber layer thicknesses, which reduces deposition time, material use, embodied energy and greenhouse gas emissions, and economic costs. Recent advances in optics, particularly in plasmonics and nanophotonics provide new theoretical methods to improve …