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Towards All-Printed Lateral Flow BiosensorsLi, Yuanhua January 2019 (has links)
Lateral flow biosensors are analytical devices that detect biomaterials with physicochemical signals, such as optical signals. Unlike other biosensors, lateral flow biosensors are based on porous membranes, which use capillary force to transport biomaterials spontaneously. However, lateral flow biosensors are fabricated in batch mode, which means that membranes need to be cut from the rolls, pretreated, and assembled using a step-by-step process. Thus, there is a need for a more efficient manufacturing process. This thesis aims to accelerate the fabrication process by developing a method wherein the whole device is printed directly, including the printable substrates, as well as by developing a clog-free process for depositing expensive reagents.
These novel printable porous media were developed using printing inks that contained various pigments and polymer binders. To this end, candidate formulations were screened from nine hundred inks formulations via wicking experiments. The results of these tests showed that the most promising formulations were based on calcium carbonates and latex polymers. This formulation was then used to develop printable porous media that can easily be printed into complex patterns, with changeable wicking speeds within each pattern. In addition, a bio- colorimetric assay of alkaline phosphates conducted on these porous media showed strong color signals that were comparable to the traditional membrane-based lateral flow strips.
Clog-free printing processes were investigated by using a piezoelectric inkjet printer to print silica sols and six nanoparticle inks. The results of these tests showed that the vibration of the piezoelectric layer and the deposition of particles on the printhead surfaces induced clogging issues. Over time, the silica sols formed multilayer deposits on the print head surface, which subsequently detached due to the vibration of the piezoelectric layer. Consequently, these large sheets of silica clogged the nozzles during printing. This clogging issue was eliminated by adjusting the pH value of the silica sol inks to 3.1. The hydrophobic cationic polystyrene nanoparticles form a sub-monolayer on the printhead surface, which causes air entrainment and promotes air bubble adhesion into the interior of the print head surface when the piezoelectric layer deforms. Thus, alternate surface chemistries for the print head and ink particle surfaces may be required in order to print hydrophobic ink materials. Overall, this enhanced understanding of these clogging mechanisms helps to explain why printer performance varies when different particles are used. / Thesis / Doctor of Philosophy (PhD) / Many devices in our day-to-day lives incorporate lateral flow biosensors, for example, home pregnancy test kits. These tests allow users to obtain results within 30 minutes by simply applying a few droplets of urine onto a test strip. However, these biosensors are largely manufactured using manual processes: workers cut strips (also called substrates) from sheets, deposit reagents onto the strips, and then assemble the pretreated strips into devices. As such, these processes are time consuming and less productive. To accelerate the manufacturing process, we developed printable porous substrates and a clog-free printing process for depositing expensive reagents onto the substrates.
Novel porous media can be flexibly printed into complex patterns using pigment- based inks. Moreover, the use of different pigments within the designed patterns enables these porous media to control wicking velocity. In addition to printable porous substrates, the research in this thesis shows that the manufacturing process can be improved by using piezoelectric inkjet printers. The use of these printers not only allows the expensive reagents to be precisely deposited onto the substrates, but it also offers a more cost-effective method of doing so. Finally, in order to ensure the printing process remained clog-free, we systematically investigated clogging mechanisms by printing with different polymers and nanoparticles.
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Fabrication and Characterization of Lithium-ion Battery Electrode Filaments Used for Fused Deposition Modeling 3D PrintingKindomba, Eli 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Lithium-Ion Batteries (Li-ion batteries or LIBs) have been extensively used in a wide
variety of industrial applications and consumer electronics. Additive Manufacturing (AM)
or 3D printing (3DP) techniques have evolved to allow the fabrication of complex structures of various compositions in a wide range of applications.
The objective of the thesis is to investigate the application of 3DP to fabricate a LIB, using
a modified process from the literature [1]. The ultimate goal is to improve the electrochemical performances of LIBs while maintaining design flexibility with a 3D printed 3D architecture.
In this research, both the cathode and anode in the form of specifically formulated slurry
were extruded into filaments using a high-temperature pellet-based extruder. Specifically,
filament composites made of graphite and Polylactic Acid (PLA) were fabricated and tested to produce anodes. Investigations on two other types of PLA-based filament composites respectively made of Lithium Manganese Oxide (LMO) and Lithium Nickel Manganese Cobalt Oxide (NMC) were also conducted to produce cathodes. Several filaments with various materials ratios were formulated in order to optimize printability and battery capacities. Finally, flat battery electrode disks similar to conventional electrodes were fabricated using the fused deposition modeling (FDM) process and assembled in half-cells and full cells. Finally, the electrochemical properties of half cells and full cells were characterized. Additionally, in parallel to the experiment, a 1-D finite element (FE) model was developed to understand the electrochemical performance of the anode half-cells made of graphite. Moreover, a simplified machine learning (ML) model through the Gaussian Process Regression was used to predict the voltage of a certain half-cell based on input parameters such as charge and discharge capacity.
The results of this research showed that 3D printing technology is capable to fabricate
LIBs. For the 3D printed LIB, cells have improved electrochemical properties by increasing
the material content of active materials (i.e., graphite, LMO, and NMC) within the PLA matrix, along with incorporating a plasticizer material. The FE model of graphite anode showed a similar trend of discharge curve as the experiment. Finally, the ML model demonstrated a reasonably good prediction of charge and discharge voltages.
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Habitat on MarsHadkar, Aditi Anil 31 May 2024 (has links)
The information contained in this thesis explores ways to develop a habitat for human settlement on Mars. Currently, most designs for living on Mars focus primarily on survival and emphasize the technological aspects necessary for sustaining life. However, there is a lack of holistic consideration for what life on Mars would entail beyond mere survival.
These existing designs are understandably geared towards astronauts who will spend only a few months on Mars. In contrast, this project is dedicated to envisioning the future of Mars settlement, aiming to support astronauts who intend to permanently live and establish communities on Mars, ultimately transforming them into Martians.
The project adopts a human-centric approach by integrating biophilic design principles to enhance the well-being of future Martian inhabitants. It seeks to address potential psychological challenges that settlers on Mars may encounter, offering innovative solutions rooted in biophilia. This approach aims to create environments that foster connection with nature, promote mental health, and support overall quality of life for individuals living on Mars.
Humans have evolved over millions of years to thrive on Earth, and many of our primal instincts are deeply rooted in our hunter-gatherer ancestry. Transitioning humans to live on another planet would uproot them from their natural environment, potentially depriving them of these primal instincts and causing psychological challenges. (Szocik, n.d.) This project aims to address these issues through architectural solutions. By designing habitats that consider and accommodate our innate instincts and connections to nature, we can mitigate the psychological impacts of living on a different planet. The goal is to create environments on Mars that resonate with our evolutionary heritage, fostering psychological well-being and adaptation in extra-terrestrial settlements. / Master of Architecture / This thesis looks at how to create a habitat for humans to live on Mars. Right now, most designs focus mainly on survival and the technology needed to sustain life. Most don't really consider what everyday life would be like beyond just staying alive.
Most current designs are for astronauts who will only be on Mars for a few months. This project, however, imagines a future where people live on Mars permanently and form communities, essentially becoming Martians.
The project uses a design method that focuses on human needs at a subconscious and psychological level. It incorporates biophilic design principles, which emphasize our connection to nature, to improve the well-being of future Martian inhabitants.
This approach aims to address psychological challenges that settlers on Mars might face, offering innovative solutions based on biophilia. The goal is to create environments that foster a connection with nature, promote mental health, and support a good quality of life.
Humans have evolved over millions of years to live on Earth, and many of our basic instincts are tied to our hunter-gatherer ancestors. Moving to another planet could take us away from our natural environment and cause psychological challenges.
This project aims to tackle these issues through thoughtful architectural design. By creating habitats that consider our natural instincts and connections to nature, we can reduce the psychological impacts of living on Mars. The goal is to design environments that align with our evolutionary background, helping people adapt and thrive in extra-terrestrial settlements.
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Moon base: ad lunamVoelcker, Ana Carolina January 2023 (has links)
The Moon is the closest celestial body to us. It is also the one we know most about, the only one we have visited so far, and our constant companion. With NASA's new Artemis program and newfound interest in exploring the Moon and beyond, my proposal is to create a base on the Moon for further space exploration, scientific development and establishment of an extraterrestrial colony. Dealing with obstacles such as lack of resources, radiation and no atmosphere, my project combines different constructive strategies, such as 3D-printing, excavating and inflatable membranes, to create an environment where humans can live and thrive on the Moon. The habitat allows for performing experiments and engaging in the basic survival activities, but also creates a home in such a challenging and distant place. Creating varied layers of habitability and protection ensure for a productive and entertaining existence on our one and only satellite, paving way to further explore the Solar System.
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Novel Gel-Infused Additively Manufactured Hybrid Rocket Solid FuelsMeier, James Hurley 28 March 2023 (has links)
In the aerospace propulsion sector safety is an important driver to costs, vehicle design and mission capabilities. Hybrid rockets are considered some of the safest forms of chemical propulsion. That factor alone makes hybrid rocket propulsion systems desirable options.
Hybrid systems often benefit from multiple additional advantages over conventional solid and liquid propellant systems, including: minimal environmental impact, higher density impulses, start-stop-restart capabilities, simplistic random throttle control, low development costs, and basic transportation and storage requirements.
A major issue that continues to impact the effective use of hybrid systems, is that classical hybrid rocket fuels suffer in low regression rates. If fuel regression rates can be improved upon without diminishing any of the other beneficial factors to a hybrid rocket motor then a far greater market for such systems can be generated.
In this work, additively manufactured polypropylene solid fuel grains were infused with gels as a means of significantly altering the fuel burning rates in a lab scale hybrid rocket motor.
Gels based on Jet-A were created using both particulate (fumed silica, micro aluminum, nano aluminum) and polymeric (paraffin wax) gellants. The particle structure of the aluminum powders was characterized by means of microscopic imaging, particle size measurement, and thermal mass response analysis. The rheological behavior of the gels was characterized in order to determine the relationship between melt layer viscosity, viscoelastic properties, and combustion performance. High speed color video recording was used on select grains for spatially and temporally resolved three-color camera pyrometry analysis. The process showed promise in determining aluminized gel burn time across an entire rocket firing. The performance of the gel infused grains was compared to a traditional center perforated fuel grain, under similar flows of gaseous oxygen. Rocket motors fired with gel infused grains exhibited pressure increases of greater than 40%. Gel infused fuel grains demonstrated regression rate enhancements up to 90% higher than the baseline. The estimated gel regression rates were over 500% higher than the host polypropylene fuel. When the O/F was maintained near stoichiometric or lean conditions, c∗ efficiencies of the gel infused grains were similar to that of the baseline indicating thorough combustion of the gels. At low oxygen mass flows, the effects of gel infusion are not as significant, which is consistent with the liquefying fuel entrainment concept. / Master of Science / In the field of air and space flight, safety is an important driver to costs, vehicle design and mission capabilities. Hybrid rockets are considered some of the safest forms of vehicle lift systems compared to similar forms. That factor alone makes hybrid rockets desirable options.
Hybrid systems often benefit from multiple additional advantages over similar systems often used, including: minimal environmental impact, greater force for a given time and volume of fuel, start-stop-restart capabilities, simplistic random motor control, low development costs, and basic transportation and storage requirements.
A major issue that continues to impact the effective use of hybrid systems is that classical hybrid rocket fuels suffer in low burn rates. If fuel burn rates can be improved upon without diminishing any of the other beneficial factors to a hybrid rocket motor then a far greater market for such systems can be generated.
In this work, specially manufactured solid fuel grains were combined with gels as a means of significantly altering the fuel burning rates in a small scale test setup. Gels based on a type of jet fuel were created using multiple gel forming and modifying materials. The structure of two types of small scale aluminum powders was characterized by means of microscopic imaging, particle size measurement, and weight response to thermal changes. Properties specific to the gels were characterized in order to determine performance relationships to individual material properties. High speed color video recording was used on select grains for space and time resolved three-color camera temperature analysis. The process showed promise in determining aluminized gel burn time across an entire rocket firing. The performance of the gel modified grains was compared to a traditional fuel grain design, under similar flows of gaseous oxygen. Rocket motors fired with gel modified grains exhibited pressure increases of greater than 40%. Gel modified fuel grains demonstrated burn rate enhancements up to 90% higher than the traditional fuel grain design. The estimated gel burn rates were over 500% higher than the host polypropylene fuel. When ideal conditions were maintained, fuel burn efficiencies of the gel modified grains were similar to that of the traditional fuel grain design indicating ideal burning of the gels. At low oxygen flow rates, the effects of gel addition are not as significant, which is consistent with an expectant similar concept.
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Printing on Objects: Curved Layer Fused Filament Fabrication on Scanned Surfaces with a Parallel Deposition MachineCoe, Edward Olin 21 June 2019 (has links)
Consumer additive manufacturing (3D printing) has rapidly grown over the last decade. While the technology for the most common type, Fused Filament Fabrication (FFF), has systematically improved and sales have increased, fundamentally, the capabilities of the machines have remained the same. FFF printers are still limited to depositing layers onto a flat build plate. This makes it difficult to combine consumer AM with other objects. While consumer AM promises to allow us to customize our world, the reality has fallen short.
The ability to directly modify existing objects presents numerous possibilities to the consumer: personalization, adding functionality, improving functionality, repair, and novel multi-material manufacturing processes. Indeed, similar goals for industrial manufacturing drove the research and development of technologies like direct write and directed energy deposition which can deposit layers onto uneven surfaces.
Replicating these capabilities on consumer 3-axis FFF machines is difficult mainly due to issues with reliability, repeatability, and quality. This thesis proposes, demonstrates, and tests a method for scanning and printing dimensionally-accurate (unwarped) digital forms onto physical objects using a modified consumer-grade 3D printer. It then provides an analysis of the machine design considerations and critical process parameters. / Master of Science / Consumer additive manufacturing (3D printing) has rapidly grown over the last decade. While the technology for the most common type, Fused Filament Fabrication (FFF), has systematically improved and sales have increased, fundamentally, the capabilities of the machines have remained the same. FFF printers are still limited to depositing layers onto a flat build plate. This makes it difficult to combine consumer AM with other objects. While consumer AM promises to allow us to customize our world, the reality has fallen short.
The ability to directly modify existing objects presents numerous possibilities to the consumer: personalization, adding functionality, improving functionality, repair, and novel multi-material manufacturing processes. Indeed, similar goals for industrial manufacturing drove the research and development of technologies like direct write and directed energy deposition which can deposit layers onto uneven surfaces.
Replicating these capabilities on consumer 3-axis FFF machines is difficult mainly due to issues with reliability, repeatability, and quality. This thesis proposes, demonstrates, and tests a method for scanning and printing dimensionally-accurate (unwarped) digital forms onto physical objects using a modified consumer-grade 3D printer. It then provides an analysis of the machine design considerations and critical process parameters.
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Legibility determinations of multiple carbon copiesBullington, Edward Weeks January 1948 (has links)
M.S.
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The Development of a Printable Device with Gravity-Driven Flow for Live Imaging Glioma Stem Cell MotilityMacias-Orihuela, Yamilet 25 January 2023 (has links)
The post-prognosis lifespan for those suffering with Glioblastoma (GBM) is approximately 13 months with current standard of care. Intratumoral heterogeneity is a common characteristic that hinders GBM treatment in the form of therapy resistant cell subsets and influence on cellular phenotypes. One cell subset in particular, glioma stem cells (GSCs), is frequently left behind in the brain parenchyma once the bulk of the tumor has been resected. Previous research has found that patient-derived GSCs displayed varying invasion responses with and without the presence of interstitial flow. Interestingly, GSCs from a single patient are heterogeneous, displaying differences among sub-colonies derived from the same parental line. To study the motility of cells under flow, PDMS microfluidics are commonly used. Unfortunately, this setup often involves active flow generation using pumps, limiting the number of cell lines that can be imaged at a time. To increase the throughput of GSC sub-colonies imaged simultaneously, we developed a bio-compatible, printable device fabricated to allow for passive, gravity-driven flow through a hydrogel that recapitulates the brain microenvironment, eliminating the need for pumps. Stereo lithography 3D printing was chosen as the manufacturing method for the device, and this facilitated design feature modification when prototyping, increased the potential complexity of future iterations, and avoided some of the hurdles associated with fabricating PDMS microfluidics. This printable imaging device allows for higher throughput live-imaging of cell lines to aid in the understanding of the relationships between intratumoral heterogeneity, invasion dynamics, and interstitial flow. / Master of Science / For those suffering with Glioblastoma, a high-grade brain cancer, the life span post treatment is approximately 13 months. The cells in this and many forms of cancer have physical and biological differences that make successfully eliminating the disease difficult. One of the cell types contributing to this are Glioma Stem Cells (GSCs) that are often left in brain tissue once most of the tumor has been surgically removed. Previous research has found that GSCs from different sources had different responses with and without the simulated or actual presence of flow in brain tissue. This was further complicated when different responses were observed in cells obtained when breaking apart one of the cell lines and propagating these into their own sub-colonies.
The current standard for studying the movement of cells under flow is by using compact chips made of a clear silicone rubber. The setup with microfluidics typically requires connection to external tubing and pumps to create flow and this limits the amount of cell types that can be imaged at a time. In order to monitor more cells at a time we created a 3D printable device that uses gravity for flow to go through a gel that mimics brain tissue and these cells of interest. Resin 3D printing was used to make these small devices so that they could be easily re-designed for other experimental purposes in the future. Hopefully this device could be used to more rapidly gain an understanding of cell movement in GBM and other disease models.
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MODELING FATIGUE BEHAVIOR OF 3D PRINTED TITANIUM ALLOYSSanket Mukund Kulkarni (19194619) 03 September 2024 (has links)
<p dir="ltr">Repeated loading and unloading cycles lead to the formation of strain in the material which causes initiation of the crack formation this phenomenon is called fatigue. Fatigue properties are critical for structures subject to cyclic load; hence fatigue analysis is used to predict the life of the material. Fatigue analysis plays an important role in optimizing the design of the 3D printed material and predicting the fatigue life of the 3D printed component.</p><p><br></p><p dir="ltr">The main objective of this thesis is to predict the fatigue behavior of different microstructures of Ti-64 titanium alloy by using the PRISMS-Fatigue open-source framework. To achieve this goal Ti-64 microstructure models were created using programming scripts, then the structures were exported to a finite element visualization software package, with all the required properties embedded in the pipeline. The PRISMS-Fatigue framework is used to conduct a fatigue analysis on 3D printed materials, using the Fatigue Indicator Parameters (FIP), which measure the driving force of fatigue crack formation in the microstructurally small crack growth.</p><p><br></p><p dir="ltr">Three different microstructures, i.e., cubic equiaxed, random equiaxed, and rolled equiaxed microstructures, are analyzed. The FIP results show that the cubic equiaxed grains have the best fatigue resistance due to their isotropic structural characteristics. Additionally, the grain size effect using 1 and 10 micrometers is investigated. The results show that the 1 micrometer grain size cubic equiaxed microstructure has a better fatigue resistance because as grains are small and they have a higher mechanical strength.</p>
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Multiphysics Modeling Of Devices For Whole Organ Healthcare ApplicationsTong, Yuxin 12 June 2017 (has links)
In order to fully understand the functionality of conformal devices, it is critical to develop computational models built from engineered models of 3-dimensional objects. This thesis established a scanning procedure to engineering 3D digital model for whole organs, known as template engineering. The resultant scanning data enabled designing, manufacturing, and modeling of novel organ healthcare devices. Specifically, we applied template engineering and structured-light scanning techniques to capture the 3D topographical information for whole organ systems. Sequentially, we developed multiphysics models for understanding the device functionality, including the function of devices for microfluidic interface and whole organ mechanical stabilization. / Master of Science / This study facilitated the development of computational models for whole organ healthcare devices. In order to develop a fundamental understanding of conforming biomedical devices for kidney assessment computational models were developed that simulate the interaction between the device and the soft organ. In this work, we generated a digital reconstruction of a porcine kidney model by surface scanning techniques that served as the domain two types of organ-devices interaction simulations: 1) organ-fluid contact problems and 2) organ-solid contact problems. This study proved that multiphysics modeling offers the potential toward the design and modeling of next-generation biomedical devices for whole organ healthcare.
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