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Articles 1651 - 1680 of 2631

Full-Text Articles in Engineering

Catalytic Hydrotreatment For The Development Of Renewable Transportation Fuels, Lilu Funkenbusch Jan 2017

Catalytic Hydrotreatment For The Development Of Renewable Transportation Fuels, Lilu Funkenbusch

Dissertations, Master's Theses and Master's Reports

Biologically-derived feedstocks are a highly desirable source of renewable transportation fuel. They can be grown renewably and can produce fuels similar in composition to conventional fossil fuels. They are also versatile and wide-ranging. Plant oils can produce renewable diesel and wood-based pyrolysis oils can be made into renewable gasoline. Catalytic hydrotreatment can be used to reduce the oxygen content of the oils and increase their viability as a “drop-in” transportation fuel, since they can then easily be blended with existing petroleum-based fuels. However, product distribution depends strongly on feedstock composition and processing parameters, especially temperature and type of catalyst. Current …


Experimental Investigations Of Temperature Controlled Innovative Annular Flow-Boiling Of Fc-72 In Millimeter Scale Ducts – Steady And Enhanced Pulsatile Realizations, Patcharapol Gorgitrattanagul Jan 2017

Experimental Investigations Of Temperature Controlled Innovative Annular Flow-Boiling Of Fc-72 In Millimeter Scale Ducts – Steady And Enhanced Pulsatile Realizations, Patcharapol Gorgitrattanagul

Dissertations, Master's Theses and Master's Reports

Steady and steady-in-the-mean shear driven annular flow-boiling is experimentally investigated in this thesis. By annular flow-regime one means separated liquid and vapor flows with the flowing liquid film staying on the boiling-surface.

The goals for the steady annular flow-boiling operations are to better understand relative importance of heat-transfer mechanisms (nucleation versus convective phase-change, with convective meaning absence of nucleation) and to develop better quantitative characterizations/correlations for heat-transfer rates. The goals for the steady-in-the-mean annular investigations was to explore improved means of significantly increasing heat transfer rates - while retaining the flow-regime's annularity.

The experimental investigations (with FC-72 as a working …


Bruise Detection In Apples Using 3d Infrared Imaging And Machine Learning Technologies, Zilong Hu Jan 2017

Bruise Detection In Apples Using 3d Infrared Imaging And Machine Learning Technologies, Zilong Hu

Dissertations, Master's Theses and Master's Reports

Bruise detection plays an important role in fruit grading. A bruise detection system capable of finding and removing damaged products on the production lines will distinctly improve the quality of fruits for sale, and consequently improve the fruit economy. This dissertation presents a novel automatic detection system based on surface information obtained from 3D near-infrared imaging technique for bruised apple identification. The proposed 3D bruise detection system is expected to provide better performance in bruise detection than the existing 2D systems.

We first propose a mesh denoising filter to reduce noise effect while preserving the geometric features of the meshes. …


Effect Of Spark Advance And Fuel On Knocking Tendency Of Spark Ignited Engine, Abhay S. Joshi Jan 2017

Effect Of Spark Advance And Fuel On Knocking Tendency Of Spark Ignited Engine, Abhay S. Joshi

Dissertations, Master's Theses and Master's Reports

Knock, in spark ignition engine is the combustion caused by the autoignition of the fuel-air mixture. It is the phenomenon that limits engine performance and thermal efficiency. Knock also has an adverse effect on emissions and fuel economy. Engine designers target engines with maximum power and torque output without compromising on fuel economy. Engine downsizing is the method generally adopted. The main goal of engine downsizing is to achieve better fuel economy while increasing the power and torque output of the engine. Better fuel economy is achieved by reducing the displaced volume which in turn means a much higher brake …


Simulation Of Diesel Particulate Filter Regeneration Using Lattice Boltzmann Method, Kshitiz Kumar Jain Jan 2017

Simulation Of Diesel Particulate Filter Regeneration Using Lattice Boltzmann Method, Kshitiz Kumar Jain

Dissertations, Master's Theses and Master's Reports

Lattice Boltzmann Method is a novel approach, which has shown promise in solving a wide variety of fluid flow problems including single and multi-phase flows in complex geometries. Volume elements of the fluid domain are considered to be composed of particles and these particles fall under a velocity distribution function at each grid point. Particles collide with each other under the influence of external forces and the rules of collision are defined so as to be compatible with the Navier-Stokes Equation. In the current work, LBM has been applied to Diesel Particulate filters which is a device used for reducing …


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 …


Turbulent Transition Simulation And Particulate Capture Modeling With An Incompressible Lattice Boltzmann Method, John R. Murdock Jan 2017

Turbulent Transition Simulation And Particulate Capture Modeling With An Incompressible Lattice Boltzmann Method, John R. Murdock

Dissertations, Master's Theses and Master's Reports

Derivation of an unambiguous incompressible form of the lattice Boltzmann equation is pursued in this dissertation. Further, parallelized implementation in developing application areas is researched. In order to achieve a unique incompressible form which clarifies the algorithm implementation, appropriate ansatzes are utilized. Through the Chapman-Enskog expansion, the exact incompressible Navier-Stokes equations are recovered. In initial studies, fundamental 2D and 3D canonical simulations are used to evaluate the validity and application, and test the required boundary condition modifications. Several unique advantages over the standard equation and alternative forms found in literature are found, including faster convergence, greater stability, and higher fidelity …


A Testbed Design For Monitoring The Long-Term Spatial-Temporal Dynamics Of Underwater Acoustic Channels, Krishna Chaitanya Poduru Jan 2017

A Testbed Design For Monitoring The Long-Term Spatial-Temporal Dynamics Of Underwater Acoustic Channels, Krishna Chaitanya Poduru

Dissertations, Master's Theses and Master's Reports

The underwater acoustic network testbed helps to validate the theoretical results and bridge the gap between experimental results. Characterizing and modeling the spatial-temporal dynamics of underwater acoustic channels is essential to developing efficient and effective physical-layer communication algorithms and network protocols. This work dedicates to designing a testbed system to measure the spatial-temporal dynamics of underwater acoustic channels. The collected measurements will shed insights into the spatial-temporal correlation of underwater acoustic channels and will be used to evaluate the theoretical algorithms that are designed to model the spatial-temporal dynamics and to exploit the spatial-temporal dynamics for more efficient and effective …


Characterization Of Kinetics And Performance In A Microbial Fuel Cell Supplied With Synthetic Landfill Leachate, Zhimin Song Jan 2017

Characterization Of Kinetics And Performance In A Microbial Fuel Cell Supplied With Synthetic Landfill Leachate, Zhimin Song

Dissertations, Master's Theses and Master's Reports

Biodegradable municipal solid waste (MSW) is rich in biochemical energy; however, much of this energy is sequestered in conventional landfills. Although bioreactor landfills enhance conversion of MSW to methane, the generated methane is a potent greenhouse gas and cannot be fully captured in landfills. Microbial fuel cells (MFCs) can directly convert the biochemical energy in MSW to electricity, treat leachate, extend landfill longevity, and minimize fugitive methane emissions. However, the electricity production from MFCs cannot yet meet the energy demands of treatment and improvements in the performance of leachate-fed MFCs are needed. Effective approaches for the design and operation of …


Electromagnetic Signal Feedback Control For Proximity Detection Systems, Adam K. Smith Jan 2017

Electromagnetic Signal Feedback Control For Proximity Detection Systems, Adam K. Smith

Dissertations, Master's Theses and Master's Reports

Coal is the most abundant fossil fuel in the United States and remains an essential source of energy. While more than half of coal production comes from surface mining, nearly twice as many workers are employed by underground operations.

One of the key pieces of equipment used in underground coal mining is the continuous mining machine. These large and powerful machines are operated in confined spaces by remote control. Since 1984, 40 mine workers in the U. S. have been killed when struck or pinned by a continuous mining machine. It is estimated that a majority of these accidents could …


Detection Of Fatigue Damage In Shear Connections Using Acoustic Wave Propagation, Zichao Wang Jan 2017

Detection Of Fatigue Damage In Shear Connections Using Acoustic Wave Propagation, Zichao Wang

Dissertations, Master's Theses and Master's Reports

Fatigue damage is an important concern in structural steel connections where frequent load reversals are expected. Detection of fatigue damage is typically done with infrequent visual inspections that are subjective and limited to surface features. A permanent embedded structural health monitoring (SHM) system could be helpful in detecting damage as it occurs. Current methods for detecting fatigue damage include inference of fatigue life expended through cycle counting from long-term strain measurement campaigns, and through short-term impedance measurements. The first approach has the advantage that it is relatively simple from an algorithmic point of view, but it is an indirect measure …


A 3 D- Fem Study On The Stress Distributions In Pediatric Skull Due To Impact From Free Fall, Suryanshu Walvekar Jan 2017

A 3 D- Fem Study On The Stress Distributions In Pediatric Skull Due To Impact From Free Fall, Suryanshu Walvekar

Dissertations, Master's Theses and Master's Reports

Abstract

Brain is vulnerable to injuries even from low heights of fall. There are many infant casualties who get severe brain injury each year. This research is a simulated study of the stress patterns and values when human infant skull is subjected to free fall. The input velocity was calculated using simple free fall velocity formulas and was fed into the simulation. Model was meshed and refined using Hypermesh software. RADIOSS solver of the Hyperworks package was used to analyze and draw results for the simulation process. Various types of stresses and strains were extracted and plotted against respective drop …


A 3d Fem Comparative Study On The Impact Response Between Human Head And Nocsae Head Due To Free Fall, Amey S. Badhe Jan 2017

A 3d Fem Comparative Study On The Impact Response Between Human Head And Nocsae Head Due To Free Fall, Amey S. Badhe

Dissertations, Master's Theses and Master's Reports

We all enjoy sports be it watching or playing. Concussion is well known topic when it comes sports related injuries. However, concussion and brain injury is not exclusive to sports and outdoor activities. Sometimes, even the impact due to slip and fall at small heights can cause serious damage to the head and brain. This report studies the response generated in the human head model and the commercially use dummy NOCSAE headform due to drop from height of 2, 3, 4 and 5 feet. Earlier studies have related brain kinetics and head kinematics to concussion and traumatic brain injury (TBI). …


Performance Simulation And Optimization Of A Simultaneous Transmit And Receive Phased Antenna Array Using Adaptive Beamforming And Genetic Algorithm Techniques, Ian Thomas Cummings Jan 2017

Performance Simulation And Optimization Of A Simultaneous Transmit And Receive Phased Antenna Array Using Adaptive Beamforming And Genetic Algorithm Techniques, Ian Thomas Cummings

Dissertations, Master's Theses and Master's Reports

The development of simultaneous transmit and receive capabilities is on the cutting-edge of research in phased array technology [1, 2, 3]. The large disparity in power between the transmitted and received signals in antenna systems has traditionally prevented operation in a simultaneous mode. However, simultaneous transmit and receive offers great opportunities for increased capabilities and performance in communications, radar, and electronic warfare applications [3]. This technology will be made feasible by realizing a high level of isolation between the transmitted and received signals through a variety of techniques. This work explores the feasibility of choosing non-standard array partitions that--when paired …


Investigation Of The Use Of 3-D Printer Platform As Building Block For Rapid Design Of Research And Manufacturing Tool, Handy Chandra Jan 2017

Investigation Of The Use Of 3-D Printer Platform As Building Block For Rapid Design Of Research And Manufacturing Tool, Handy Chandra

Dissertations, Master's Theses and Master's Reports

This thesis attempts to show how an open source 3-D printer platform, the self replicating rapid prototype (RepRap), could be used to accelerate the development of research and manufacturing tools. Two projects are shown as examples, both utilizing components of the 3-D printer platform.

The first project is to develop an instrument capable of performing automated large-area four-point probe measurements. A modified RepRap 3-D Printer with a four-point probe in place of the 3-D printer head is utilized as a precision positioning platform. The printer together with custom designed measurement circuit and software performs automated measurement on multiple points on …


Consensus Based Distributed Control In Micro-Grid Clusters, Syed Ahmed Fuad Jan 2017

Consensus Based Distributed Control In Micro-Grid Clusters, Syed Ahmed Fuad

Dissertations, Master's Theses and Master's Reports

With the increasing trend of utilizing renewable energy generators such as photovoltaic (PV) cells and wind turbines, power systems are transforming from a centralized power grid structure to a cluster of smart micro-grids with more autonomous power sharing capabilities. Even though the decentralized control of power systems is a reliable and cost effective solution, due to the inherent heterogeneous nature of micro-grids, optimal and efficient power sharing among distributed generators (DG’s) is a major issue which calls for advanced control techniques for voltage stabilization of the entire micro-grid cluster. The proposed consensus based algorithm in this thesis is a solution …


A Wireless, Passive Sensor For Measuring Temperature At Orthopedic Implant Sites For Early Diagnosis Of Infections, Salil Sidharthan Karipott Jan 2017

A Wireless, Passive Sensor For Measuring Temperature At Orthopedic Implant Sites For Early Diagnosis Of Infections, Salil Sidharthan Karipott

Dissertations, Master's Theses and Master's Reports

Sensorized implants with embedded wireless, passive temperature sensors were developed for early detection of implant-associated infections. The operation principle of the sensor is based on the hypothesis that infections can lead to an increase in local temperature prior to the rise of body temperature. The sensor was an inductive capacitive (LC) circuit that has been used for monitoring of different parameters wirelessly, often in difficult to access environments. The sensor was fabricated on to an interference screw, which is used for tendon and ligament reconstruction surgeries. In this project, a sensorized interference screw was designed and fabricated by accommodating an …


Incorporation Of Higher Carbon Number Alcohols In Gasoline Blends For Application In Spark-Ignition Engines, Kristina Lawyer Jan 2017

Incorporation Of Higher Carbon Number Alcohols In Gasoline Blends For Application In Spark-Ignition Engines, Kristina Lawyer

Dissertations, Master's Theses and Master's Reports

The 2007 U.S. Renewable Fuel Standard (RFS2) requires an increase in the use of advanced biofuels up to 36 billion gallons by 2022. Higher carbon number alcohols, in addition to cellulosic ethanol and synthetic biofuels, could be used to meet this demand while adhering to the RFS2 corn-based ethanol limitation. Alcohols of carbon numbers 2 through 8 are chosen based on their chemical and engine-related properties.

Blend comparison metrics are developed from automotive industry trends, consumer expectations, U.S. fuel legislation, and engine requirements. The metrics are then used to create scenarios by which to compare higher alcohol fuel blends to …


Implantable Wireless Sensor Networks: Application To Measuring Temperature For In Vivo Detection Of Infections, Praharsh Madappaly Veetil Jan 2017

Implantable Wireless Sensor Networks: Application To Measuring Temperature For In Vivo Detection Of Infections, Praharsh Madappaly Veetil

Dissertations, Master's Theses and Master's Reports

It is has been proven that infection in the body cause a local temperature increase due to localized inflammation. Therefore, a method to provide early diagnostic or long-term tracking of this infection will provide great benefits to patients with diabetic foot ulcers or sickle cell disease, and those receiving hemodialysis where they suffer from a weakened immune system. The goal of this project is to develop an implantable wireless temperature sensor based on a wireless sensor network system for monitoring infections in situ. The analog signals from the thermistors are digitized and wirelessly transmitted to a computer with an ez430-rf2500 …


Design Automation For Carbon Nanotube Circuits Considering Performance And Security Optimization, Lin Liu Jan 2017

Design Automation For Carbon Nanotube Circuits Considering Performance And Security Optimization, Lin Liu

Dissertations, Master's Theses and Master's Reports

As prevailing copper interconnect technology advances to its fundamental physical limit, interconnect delay due to ever-increasing wire resistivity has greatly limited the circuit miniaturization. Carbon nanotube (CNT) interconnects have emerged as promising replacement materials for copper interconnects due to their superior conductivity. Buffer insertion for CNT interconnects is capable of improving circuit timing of signal nets with limited buffer deployment. However, due to the imperfection of fabricating long straight CNT, there exist significant unidimensional-spatially correlated variations on the critical CNT geometric parameters such as the diameter and density, which will affect the circuit performance.

This dissertation develops a novel timing …


Impact Of E20 Fuel On A High-Performance, Two-Stroke Engine, Jon Gregory Loesche Jan 2017

Impact Of E20 Fuel On A High-Performance, Two-Stroke Engine, Jon Gregory Loesche

Dissertations, Master's Theses and Master's Reports

The purpose of this project was to explore the emissions, combustion, and performance effects of running a gasoline/ethanol fuel mixture of 20 percent by volume (E20) in a fuel-injected, two-stroke engine. The engine was operated at five engine speeds that corresponded with the EPA 5-mode emissions test for snowmobile engines. Single parameter sweeps were conducted along with a preliminary recalibration of the test engine at two E0 target values (lambda and mid-pipe temperature) using E20 fuel.

Baseline testing showed that running E20 fuel produced a leaner air/fuel mixture compared to E0, resulting in higher lambda values for all modes and …


Frontal Crash Analysis Of A Conformable Cng Tank Using Finite Element Analysis, Datta Sandesh Manjunath Jan 2017

Frontal Crash Analysis Of A Conformable Cng Tank Using Finite Element Analysis, Datta Sandesh Manjunath

Dissertations, Master's Theses and Master's Reports

The purpose of this study is to computationally model and analyze a Conformable Compressed Natural Gas (CNG) fuel tank for frontal crashes using Finite Element Analysis. Researchers have developed a CNG fuel tank, which is conformable, non-conventional and non-cylindrical. This tank increases cost efficiency, volumetric efficiency and cargo efficiency in CNG vehicle applications. A lightweight pickup truck (2015 Chevrolet Silverado) has been used to integrate the CNG tanks and field-testing has been conducted to demonstrate the application.

The report mainly focuses on the effective finite element modeling of the chassis, brackets and tanks using HYPERMESH and RADIOSS. The frontal crash …


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 …


Second-Life Battery Electrochemical Impedance Spectroscopy Modeling And Application To A Residential System, Busra Ovali Jan 2017

Second-Life Battery Electrochemical Impedance Spectroscopy Modeling And Application To A Residential System, Busra Ovali

Dissertations, Master's Theses and Master's Reports

This study presents the modeling of a used hybrid electric vehicle battery (also called second life battery), and its design and simulation for a standalone residential photovoltaic system. For this purpose, the battery was tested through capacity and electrochemical impedance spectroscopy tests (EIS). These tests were done with variable temperatures (0ºC, 15ºC and 30ºC), and results were used to fit an equivalent impedance circuit. This model was used to incorporate a second life battery to a PV system, which was simulated by using daily irradiance and load data for Tucson (AZ) under most various month (May).


Low-Cost Open-Source Gmaw-Based Metal 3-D Printing: Monitoring, Slicer, Optimization, And Applications, Yuenyong Nilsiam Jan 2017

Low-Cost Open-Source Gmaw-Based Metal 3-D Printing: Monitoring, Slicer, Optimization, And Applications, Yuenyong Nilsiam

Dissertations, Master's Theses and Master's Reports

Low-cost and open-source gas metal arc welding (GMAW)-based 3-D printing has been demonstrated yet the electrical design and software was not developed enough to enable wide-spread adoption. This thesis provides three novel technical improvements based on the application of mechatronic and software theory that when combined demonstrate the ability for distributed digital manufacturing at the small and medium enterprise scale of steel and aluminum parts. First, low cost metal inert gas welders contain no power monitoring needed to tune GMAW 3-D printers. To obtain this data about power and energy usage during the printing, an integrated monitoring system was developed …


Feature And Decision Level Fusion Using Multiple Kernel Learning And Fuzzy Integrals, Anthony Pinar Jan 2017

Feature And Decision Level Fusion Using Multiple Kernel Learning And Fuzzy Integrals, Anthony Pinar

Dissertations, Master's Theses and Master's Reports

The work collected in this dissertation addresses the problem of data fusion. In other words, this is the problem of making decisions (also known as the problem of classification in the machine learning and statistics communities) when data from multiple sources are available, or when decisions/confidence levels from a panel of decision-makers are accessible. This problem has become increasingly important in recent years, especially with the ever-increasing popularity of autonomous systems outfitted with suites of sensors and the dawn of the ``age of big data.'' While data fusion is a very broad topic, the work in this dissertation considers …


Minimizing Run Time Of Finite Element Analyses: Applications In Conformable Cng Tank Modeling, Paul M. Roehm Jan 2017

Minimizing Run Time Of Finite Element Analyses: Applications In Conformable Cng Tank Modeling, Paul M. Roehm

Dissertations, Master's Theses and Master's Reports

REL Inc. has proposed a CNG tank that deviates from typical cylindrical storage methods. The goal of REL working with Michigan Tech is to minimize mass and meet NGV2 safety standards for pressure and drop testing for this tank.

The model has undulated outer surfaces and Schwarz P-surface internal geometry. To accurately mesh this, a small element size is necessary; this creates a model with millions of elements. In explicit analyses, this requires a large amount of computational resources to run.

This report focuses on methods to reduce model run time without reducing accuracy. Methods covered include creating symmetric building …


An Optimal Energy Management Strategy For Hybrid Electric Vehicles, Amir Rezaei Jan 2017

An Optimal Energy Management Strategy For Hybrid Electric Vehicles, Amir Rezaei

Dissertations, Master's Theses and Master's Reports

Hybrid Electric Vehicles (HEVs) are used to overcome the short-range and long charging time problems of purely electric vehicles. HEVs have at least two power sources. Therefore, the Energy Management (EM) strategy for dividing the driver requested power between the available power sources plays an important role in achieving good HEV performance.

This work, proposes a novel real-time EM strategy for HEVs which is named ECMS-CESO. ECMS-CESO is based on the Equivalent Consumption Minimization Strategy (ECMS) and is designed to Catch Energy Saving Opportunities (CESO) while operating the vehicle. ECMS-CESO is an instantaneous optimal controller, i. e., it does not …


Model-Based Control Of Hybrid Electric Powertrains Integrated With Low Temperature Combustion Engines, Ali Soloukmofrad Jan 2017

Model-Based Control Of Hybrid Electric Powertrains Integrated With Low Temperature Combustion Engines, Ali Soloukmofrad

Dissertations, Master's Theses and Master's Reports

Powertrain electrification including hybridizing advanced combustion engines is a viable cost-effective solution to improve fuel economy of vehicles. This will provide opportunity for narrow-range high-efficiency combustion regimes to be able to operate and consequently improve vehicle’s fuel conversion efficiency, compared to conventional hybrid electric vehicles (HEV)s. Low temperature combustion (LTC) engines offer the highest peak brake thermal efficiency reported in literature, but these engines have narrow operating range. In addition, LTC engines have ultra-low soot and nitrogen oxides (NOx) emissions, compared to conventional compression ignition and spark ignition (SI) engines. This dissertation concentrates on integrating the LTC engines (i) in …


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 …