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Full-Text Articles in Materials Science and Engineering

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce Jun 2020

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications, Part 1

To assist firefighters and other first responders to use their existing equipment for respiration during the COVID-19 pandemic without using single-use, low-supply, masks, this study outlines an open source kit to convert a 3M-manufactured Scott Safety self-contained breathing apparatus (SCBA) into a powered air-purifying particulate respirator (PAPR). The open source PAPR can be fabricated with a low-cost 3-D printer and widely available components for less than $150, replacing commercial conversion kits saving 85% or full-fledged proprietary PAPRs saving over 90%. The parametric designs allow for adaptation to other core components and can be custom fit specifically to fire-fighter equipment, including …


Mechanical Properties Of Boehmeria Nivea Natural Fabric Reinforced Epoxy Matrix Composite Prepared By Vacuum-Assisted Resin Infusion Molding, Fabio Da Costa Garcia Filho, Fernanda Santos Da Luz, Lucio Fabio Cassiano Nascimento, Kestur Gundappa Satyanarayana, Jaroslaw W. Drelich, Sergio Neves Monteiro Jun 2020

Mechanical Properties Of Boehmeria Nivea Natural Fabric Reinforced Epoxy Matrix Composite Prepared By Vacuum-Assisted Resin Infusion Molding, Fabio Da Costa Garcia Filho, Fernanda Santos Da Luz, Lucio Fabio Cassiano Nascimento, Kestur Gundappa Satyanarayana, Jaroslaw W. Drelich, Sergio Neves Monteiro

Michigan Tech Publications, Part 1

Natural lignocellulosic fibers and corresponding fabrics have been gaining notoriety in recent decades as reinforcement options for polymer matrices associated with industrially applied composites. These natural fibers and fabrics exhibit competitive properties when compared with some synthetics such as glass fiber. In particular, the use of fabrics made from natural fibers might be considered a more ecient alternative, since they provide multidirectional reinforcement and allow the introduction of a larger volume fraction of fibers in the composite. In this context, it is important to understand the mechanical performance of natural fabric composites as a basic condition to ensure ecient engineering …


Distributed Manufacturing Of Open Source Medical Hardware For Pandemics, Joshua M. Pearce Jun 2020

Distributed Manufacturing Of Open Source Medical Hardware For Pandemics, Joshua M. Pearce

Michigan Tech Publications, Part 1

Distributed digital manufacturing offers a solution to medical supply and technology shortages during pandemics. To prepare for the next pandemic, this study reviews the state-of-the-art of open hardware designs needed in a COVID-19-like pandemic. It evaluates the readiness of the top twenty technologies requested by the Government of India. The results show that the majority of the actual medical products have some open source development, however, only 15% of the supporting technologies required to produce them are freely available. The results show there is still considerable research needed to provide open source paths for the development of all the medical …


Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications, Part 1

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met …


Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications, Part 1

Access to nasopharyngeal swabs for sampling remain a bottleneck in some regions for COVID19 testing. This study develops a distributed manufacturing solution using only an open source manufacturing tool chain consisting of two types of open source 3-D printing and batch UV curing, and provides a parametric fully free design of a nasopharyngeal swab. The swab was designed using parametric OpenSCAD in two components (a head with engineered break point and various handles), which has several advantages: i) minimizing print time on relatively slow SLA printers, ii) enabling the use of smaller print volume open source SLA printers, iii) reducing …


Antibacterial And Anticancer Activity Of Hydrothermally-Synthesized Zinc Oxide Nanomaterials Using Natural Extracts Of Neem, Pepper And Turmeric As Solvent Media, C. Abinaya, R. Manjula Devi, P. Suresh, N. Balasubramanian, N. Muthaiya, N. D. Kannan, J. Annaraj, V. Shanmugaiah, Joshua Pearce, P. Shanmugapriya, J. Mayandi Apr 2020

Antibacterial And Anticancer Activity Of Hydrothermally-Synthesized Zinc Oxide Nanomaterials Using Natural Extracts Of Neem, Pepper And Turmeric As Solvent Media, C. Abinaya, R. Manjula Devi, P. Suresh, N. Balasubramanian, N. Muthaiya, N. D. Kannan, J. Annaraj, V. Shanmugaiah, Joshua Pearce, P. Shanmugapriya, J. Mayandi

Michigan Tech Publications, Part 1

A novel and simple wet chemical hydrothermal synthesis method was employed in the preparation of zinc oxide (ZnO) nanoparticles using neem (N), pepper (P) and turmeric (T) extracts as solvent media. The structural and optical properties as well as the antibacterial and anticancer properties of all the samples (ZnO, N/ZnO, P/ZnO, T/ZnO and NPT/ZnO) were characterized and analyzed. Solvent media was found to have an effect on both the size and the morphology of the nanoparticles, which in turn effected their optical and cytotoxic properties. The colony forming unit (CFU) assays were done for E. coli, S. aureus and S. …


Energy Conservation With Open Source Ad Blockers, Joshua M. Pearce Mar 2020

Energy Conservation With Open Source Ad Blockers, Joshua M. Pearce

Michigan Tech Publications, Part 1

Internet-related electricity consumption is rising rapidly as global Internet users spend more than 6.5 h per day online. Open source ad blockers have the potential to reduce the time and thus electricity spent using computers by eliminating ads during Internet browsing and video streaming. In this study, three open source ad blockers are tested against a no-ad blocker control. Page load time is recorded for browsing a representative selection of the globally most-accessed websites, and the time spent watching ads on videos is quantified for both trending and non-trending content. The results show that page load time dropped 11% with …


A Review Of Open Source Ventilators For Covid-19 And Future Pandemics., Joshua M. Pearce Jan 2020

A Review Of Open Source Ventilators For Covid-19 And Future Pandemics., Joshua M. Pearce

Michigan Tech Publications, Part 1

Coronavirus Disease 2019 (COVID-19) threatens to overwhelm our medical infrastructure at the regional level causing spikes in mortality rates because of shortages of critical equipment, like ventilators. Fortunately, with the recent development and widespread deployment of small-scale manufacturing technologies like RepRap-class 3-D printers and open source microcontrollers, mass distributed manufacturing of ventilators has the potential to overcome medical supply shortages. In this study, after providing a background on ventilators, the academic literature is reviewed to find the existing and already openly-published, vetted designs for ventilators systems. These articles are analyzed to determine if the designs are open source both in …


Texture Evolution Induced By Twinning And Dynamic Recrystallization In Dilute Mg-1sn-1zn-1al Alloy During Hot Compression, Meijuan Hao, Weili Cheng, Lifei Wang, Ehsan Mostaed, Liping Bian, Hongxia Wang, Xiaofeng Niu Jan 2020

Texture Evolution Induced By Twinning And Dynamic Recrystallization In Dilute Mg-1sn-1zn-1al Alloy During Hot Compression, Meijuan Hao, Weili Cheng, Lifei Wang, Ehsan Mostaed, Liping Bian, Hongxia Wang, Xiaofeng Niu

Michigan Tech Publications, Part 1

Texture evolution of an extruded dilute Mg-1Sn-1Zn-1Al alloy was thoroughly investigated based on the twinning and dynamic recrystallization (DRX) behavior via hot compression at a strain rate of 10 s−1 and temperature of 225°C. It was found that the types and intensities of the texture are strongly dependent on the fraction of twins and DRX modes as well as regions where sub-grain boundaries (sub-GBs) are intensively accumulated. At the initial stage of deformation, the formation of compression direction (CD)-tilted basal texture was mainly determined by the occurrence of {101¯2} extension twins. As the strain increases, the variation in the texture …


From Open Access To Open Science: The Path From Scientific Reality To Open Scientific Communication, Christian Heise, Joshua M. Pearce Jan 2020

From Open Access To Open Science: The Path From Scientific Reality To Open Scientific Communication, Christian Heise, Joshua M. Pearce

Michigan Tech Publications, Part 1

Although opening up of research is considered an appropriate and trend-setting model for future scientific communication, it can still be difficult to put open science into practice. How open and transparent can a scientific work be? This article investigates the potential to make all information and the whole work process of a qualification project such as a doctoral thesis comprehensively and freely accessible on the internet with an open free license both in the final form and completely traceable in development. The answer to the initial question, the self-experiment and the associated demand for openness, posed several challenges for a …


Open Source Waste Plastic Granulator, Arvind Ravindran, Sean Scsavnicki, Walker Nelson, Peter Gorecki, Jacob Franz, Shane Oberloier, Theresa K. Meyer, Andrew Barnard, Joshua M. Pearce Oct 2019

Open Source Waste Plastic Granulator, Arvind Ravindran, Sean Scsavnicki, Walker Nelson, Peter Gorecki, Jacob Franz, Shane Oberloier, Theresa K. Meyer, Andrew Barnard, Joshua M. Pearce

Michigan Tech Publications, Part 1

In order to accelerate deployment of distributed recycling by providing low-cost feed stocks of granulated post-consumer waste plastic, this study analyzes an open source waste plastic granulator system. It is designed, built, and tested for its ability to convert post-consumer waste, 3D printed products and waste into polymer feedstock for recyclebots of fused particle/granule printers. The technical specifications of the device are quantified in terms of power consumption (380 to 404 W for PET and PLA, respectively) and particle size distribution. The open source device can be fabricated for less than $2000 USD in materials. The experimentally measured power use …


Low-Cost Open Source Ultrasound-Sensing Based Navigational Support For The Visually Impaired, Aliaksei Petsiuk, Joshua M. Pearce Aug 2019

Low-Cost Open Source Ultrasound-Sensing Based Navigational Support For The Visually Impaired, Aliaksei Petsiuk, Joshua M. Pearce

Michigan Tech Publications, Part 1

Nineteen million Americans have significant vision loss. Over 70% of these are not employed full-time, and more than a quarter live below the poverty line. Globally, there are 36 million blind people, but less than half use white canes or more costly commercial sensory substitutions. The quality of life for visually impaired people is hampered by the resultant lack of independence. To help alleviate these challenges this study reports on the development of a low-cost, open-source ultrasound-based navigational support system in the form of a wearable bracelet to allow people with the lost vision to navigate, orient themselves in their …


Spontaneous Selective Deposition Of Iron Oxide Nanoparticles On Graphite As Model Catalysts, Chathura De Alwis, Timothy Leftwich, Pinaki Mukherjee, Alex Denofre, Kathryn Perrine Aug 2019

Spontaneous Selective Deposition Of Iron Oxide Nanoparticles On Graphite As Model Catalysts, Chathura De Alwis, Timothy Leftwich, Pinaki Mukherjee, Alex Denofre, Kathryn Perrine

Michigan Tech Publications, Part 1

Iron oxide nanomaterials participate in redox processes that give them ideal properties for their use as earth-abundant catalysts. Fabricating nanocatalysts for such applications requires detailed knowledge of the deposition and growth. We report the spontaneous deposition of iron oxide nanoparticles on HOPG in defect areas and on step edges from a metal precursor solution. To study the nucleation and growth of iron oxide nanoparticles, tailored defects were created on the surface of HOPG using various ion sources that serve as the target sites for iron oxide nucleation. After solution deposition and annealing, the iron oxide nanoparticles were found to nucleate …


Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce May 2019

Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications, Part 1

Past work has shown that particle material extrusion (fused particle fabrication (FPF)/fused granular fabrication (FGF)) has the potential for increasing the use of recycled polymers in 3D printing. This study extends this potential to high-performance (high-mechanical-strength and heat-resistant) polymers using polycarbonate (PC). Recycled PC regrind of approximately 25 mm2 was 3D printed with an open-source Gigabot X and analyzed. A temperature and nozzle velocity matrix was used to find useful printing parameters, and a print test was used to maximize the output for a two-temperature stage extruder for PC. ASTM type 4 tensile test geometries as well as ASTM-approved …


Systems Analysis For Pet And Olefin Polymers In A Circular Economy, David R. Shonnard, Emily Tipaldo, Vicki Thompson, Joshua M. Pearce, Gerard T. Caneba, Robert Handler May 2019

Systems Analysis For Pet And Olefin Polymers In A Circular Economy, David R. Shonnard, Emily Tipaldo, Vicki Thompson, Joshua M. Pearce, Gerard T. Caneba, Robert Handler

Michigan Tech Publications, Part 1

Polyethylene terephthalate (PET #1) and polyolefin plastics such polyethylene (HDPE #2, LDPE #4) and polypropylene (PP #5) are major products from the chemical industry, and they comprise a significant fraction of municipal solid waste that ends up in landfills or as litter and marine debris. The reuse of these polymeric materials can be optimized through systems analysis with a view on materials flow analysis, techno-economics, environmental life cycle assessment, and consequential societal impacts. This contribution will present the overall research approach for this exploratory project within the DOE- and industry-funded REMADE Institute and end with a proposed systems analysis framework.


Open Source Completely 3-D Printable Centrifuge, Salil S. Sule, Aliaksei Petsiuk, Joshua M. Pearce May 2019

Open Source Completely 3-D Printable Centrifuge, Salil S. Sule, Aliaksei Petsiuk, Joshua M. Pearce

Michigan Tech Publications, Part 1

Centrifuges are commonly required devices in medical diagnostics facilities as well as scientific laboratories. Although there are commercial and open source centrifuges, the costs of the former and the required electricity to operate the latter limit accessibility in resource-constrained settings. There is a need for low-cost, human-powered, verified, and reliable lab-scale centrifuges. This study provides the designs for a low-cost 100% 3-D printed centrifuge, which can be fabricated on any low-cost RepRap-class (self-replicating rapid prototyper) fused filament fabrication (FFF)- or fused particle fabrication (FPF)-based 3-D printer. In addition, validation procedures are provided using a web camera and free and open …


Preliminary Automated Determination Of Edibility Of Alternative Foods: Non-Targeted Screening For Toxins In Red Maple Leaf Concentrate, Joshua M. Pearce, Maryam Khaksari, David C. Denkenberger Apr 2019

Preliminary Automated Determination Of Edibility Of Alternative Foods: Non-Targeted Screening For Toxins In Red Maple Leaf Concentrate, Joshua M. Pearce, Maryam Khaksari, David C. Denkenberger

Michigan Tech Publications, Part 1

Alternative food supplies could maintain humanity despite sun-blocking global catastrophic risks (GCRs) that eliminate conventional agriculture. A promising alternative food is making leaf concentrate. However, the edibility of tree leaves is largely uncertain. To overcome this challenge, this study provides the methods for obtaining rapid toxics screening of common leaf concentrates. The investigation begins with a non-targeted approach using an ultra-high-resolution hybrid ion trap orbitrap mass spectrometer with electrospray ionization (ESI) coupled to an ultra-high pressure two-dimensional liquid chromatograph system on the most common North American leaf: the red maple. Identified chemicals from this non-targeted approach are then cross-referenced with …


Coal With Carbon Capture And Sequestration Is Not As Land Use Efficient As Solar Photovoltaic Technology For Climate Neutral Electricity Production, James Gunnar Groesbeck, Joshua M. Pearce Sep 2018

Coal With Carbon Capture And Sequestration Is Not As Land Use Efficient As Solar Photovoltaic Technology For Climate Neutral Electricity Production, James Gunnar Groesbeck, Joshua M. Pearce

Michigan Tech Publications, Part 1

Avoiding climate destabilization caused by greenhouse gas (GHG) emissions, requires climate-neutral electricity sources. It has been proposed that the GHG emissions from coal-fired power plants can be offset by carbon capture and sequestration or bio-sequestration. However, solar photovoltaic (PV) technology has recently declined so far in costs it now offers both technical and economic potential to offset all of coal-fired electricity use. PV only emits GHGs during fabrication and not during use. To determine which technical solution to climate-neutral electricity generation should be preferred, this study aggregates and synthesizes life cycle analysis studies for exergy, GHG emissions and land transformation …


Energy Science And Engineering: Looking Ahead, Yun Hang Hu Aug 2018

Energy Science And Engineering: Looking Ahead, Yun Hang Hu

Michigan Tech Publications, Part 1

No abstract provided.


Sponsored Libre Research Agreements To Create Free And Open Source Software And Hardware, Joshua M. Pearce Jul 2018

Sponsored Libre Research Agreements To Create Free And Open Source Software And Hardware, Joshua M. Pearce

Michigan Tech Publications, Part 1

As a growing number of companies reject intellectual property (IP) monopoly-based business models to embrace libre product development of free and open source hardware and software, there is an urgent need to refurbish the instruments of university-corporate research partnerships. These partnerships generally use a proprietary standard research agreement (PSRA), which for historical reasons contains significant IP monopoly language and restrictions for both the company and the university. Such standard research agreements thus create an artificial barrier to innovation as both companies using a libre model and universities they wish to collaborate with must invest significantly to restructure the contracts. To …


Effect Of Zr Additions On Thermal Stability Of Al-Cu Precipitates In As-Cast And Cold Worked Samples, Kyle Deane, Paul G. Sanders May 2018

Effect Of Zr Additions On Thermal Stability Of Al-Cu Precipitates In As-Cast And Cold Worked Samples, Kyle Deane, Paul G. Sanders

Michigan Tech Publications, Part 1

While Zr is frequently added to Al alloys to control grain size with the formation of large (>1 μm) primary precipitates, little research has been conducted on the effect of nanoscale Al3Zr precipitates on Al alloys. By comparing the precipitation and corresponding strength evolution between Al-Cu-Zr alloys with different Zr concentrations, the effects of Zr on Al-Cu precipitation with and without primary Al3Zr precipitates can be observed. In the absence of these large precipitates, all Al3Zr phases can be formed, through high temperature aging treatments, as a dispersion of nanoprecipaites inside the Al …


The Natural Aging Effect On Hardenability In Al-Mg-Si: A Complex Interaction Between Composition And Heat Treatment Parameters, Alex Poznak, Violet Thole, Paul G. Sanders May 2018

The Natural Aging Effect On Hardenability In Al-Mg-Si: A Complex Interaction Between Composition And Heat Treatment Parameters, Alex Poznak, Violet Thole, Paul G. Sanders

Michigan Tech Publications, Part 1

The technological relevance of Al-Mg-Si alloys has been rapidly growing over the last decade. Of particular interest to current and future applications is the problematic negative effect of prior natural aging on subsequent artificial age hardening. The influence of natural aging is dependent on both processing and compositional variables and has origins that are far from well-understood. This work examines the hardenability of 6000 series alloys under a wide range of conditions, paying particular attention to the natural aging effect. Experimental variables include alloy composition (Mg + Si, Mg/Si), cooling rate after solutionization, and duration of prior natural aging. Hardenability …


The Suitability Of Zn–1.3% Fe Alloy As A Biodegradable Implant Material, Alon Kafri, Shira Ovadia, Jeremy Goldman, Jaroslaw W. Drelich, Eli Aghion Feb 2018

The Suitability Of Zn–1.3% Fe Alloy As A Biodegradable Implant Material, Alon Kafri, Shira Ovadia, Jeremy Goldman, Jaroslaw W. Drelich, Eli Aghion

Michigan Tech Publications, Part 1

Efforts to develop metallic zinc for biodegradable implants have significantly advanced following an earlier focus on magnesium (Mg) and iron (Fe). Mg and Fe base alloys experience an accelerated corrosion rate and harmful corrosion products, respectively. The corrosion rate of pure Zn, however, may need to be modified from its reported ~20 µm/year penetration rate, depending upon the intended application. The present study aimed at evaluating the possibility of using Fe as a relatively cathodic biocompatible alloying element in zinc that can tune the implant degradation rate via microgalvanic effects. The selected Zn–1.3wt %Fe alloy composition produced by gravity casting …


Novel Durable Antimicrobial Ceramic With Embedded Copper Sub-Microparticles For A Steady-State Release Of Copper Ions, Adam J. Drelich, Jessie Miller, Robert Donofrio, Jaroslaw Drelich Jul 2017

Novel Durable Antimicrobial Ceramic With Embedded Copper Sub-Microparticles For A Steady-State Release Of Copper Ions, Adam J. Drelich, Jessie Miller, Robert Donofrio, Jaroslaw Drelich

Michigan Tech Publications, Part 1

Using pottery clay, porous ceramic stones were molded and then decorated with copper sub-microparticles inside the pores. Copper added antimicrobial functionality to the clay-based ceramic and showed ability in disinfecting water. Populations of both Staphylococcus aureus and Klebsiella pneumoniae in contaminated water were reduced by >99.9% in 3 h when exposed to an antimicrobial stone. This antimicrobial performance is attributed to a slow release of copper into water at both room and elevated temperatures. Copper is leached by water to produce ion concentrations in water at a level of 0.05–0.20 ppm after 24 to 72 h immersion tests. This concentration …


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 …


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 …


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 …


The Case For Open Source Appropriate Technology, Joshua M. Pearce Jun 2012

The Case For Open Source Appropriate Technology, Joshua M. Pearce

Michigan Tech Publications, Part 1

Much of the widespread poverty, environmental desecration, and waste of human life seen around the globe could be prevented by known (to humanity as a whole) technologies, many of which are simply not available to those that need it. This lack of access to critical information for sustainable development is directly responsible for a morally and ethically unacceptable level of human suffering and death. A solution to this general problem is the concept of open source appropriate technology or OSAT, which refers to technologies that provide for sustainable development while being designed in the same fashion as free and open …