Materials Science and Engineering Commons^™

Empirical Modeling Of Structural Distortions In Perovskite Ceramics, Evan Connor Smith

Boise State University Theses and Dissertations

Predictive models for composition-structure-property relationships are essential to realizing the full potential of electroceramic materials; however, the electroceramics industry has largely failed to invest in predictive models in favor of simple rules of thumb or expensive, time-consuming trial-and-error methods. Empirically derived predictive models have the potential to significantly improve and guide future research in a more cost-effective and timely manner. It may even be possible to predict some intrinsic properties (e.g., polarization) on the order of a unit cell using only the charge and size of each chemical component. Scientists and researchers may ultimately be able to use …

Peptoid And Antibody-Based Gfp Sensors, Solomon Isu

Graduate Theses and Dissertations

In this work, we have made and characterized a pair of immunobiosensors for detecting the green fluorescent protein (GFP) in an aqueous matrix. An anti-GFP antibody-based biosensor was assembled to detect GFP, while a novel peptoid (N-substituted oligomers of glycine designated as IOS-1) biosensor was also assembled for GFP detection. A quartz crystal microbalance (QCM) gold sensor was used as the supporting substrate for self-assembly of the immunobiosensors. Gravimetric measurements of the QCM gold sensor during immunobiosensor construction and operation were available in real-time using a QCM instrument. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Fluorescence microscopy were used …

Thiol-Induced Degradation Of Hydrogels Utilizing Multiresponsive Dithiomaleimides Crosslinkers, Kundu Thapa

Honors Theses

Hydrogels are hydrophilic, three-dimensional materials used as platforms for various biomedical applications such as drug delivery, biosensors, or as scaffolds in tissue engineering. The ability to degrade on demand in response to biological cues is particularly attractive whether dealing with microgels or if one aims to release an active ingredient from a scaffolding material. For instance, many cancer-remediation drug delivery platforms leverage the high concentration of glutathione, a thiol-containing tripeptide, found in cancerous cells. In this work, poly(ethylene glycol) acrylate hydrogels were fabricated using dithiomaleimide (DTM) moieties. DTMs are known to undergo thiol-exchange reactions favoring the dissolution of the hydrogel …

Monolithic Chalcogenide Optical Nanocomposites Enable Infrared System Innovation: Gradient Refractive Index Optics, Myungkoo Kang, Laura Sisken, Charmayne Lonergan, Andrew Buff, Anupama Yadav, Claudia Goncalves, Cesar Blanco, Peter Wachtel, J. David Musgraves, Alexej V. Pogrebnyakov, Erwan Baleine, Clara Rivero-Baleine, Theresa S. Mayer, Carlo G. Pantano, Kathleen A. Richardson

Materials Science and Engineering Faculty Research & Creative Works

The size and weight of conventional imaging systems is defined by costly non-planar lenses and the complex lens assemblies required to minimize optical aberrations. The ability to engineer gradient refractive index (GRIN) optics has the potential to overcome constraints of traditional homogeneous lenses by reducing the number of components in optical systems. Here, an innovative strategy to realize this goal based on monolithic GRIN media created in Ge-As-Se-Pb chalcogenide infrared nanocomposites is presented. A gradient heat treatment to spatially modulate the volume fraction of high refractive index Pb-rich nanocrystals within a glass matrix is utilized, providing a GRIN profile while …

Spherical Cavity Expansion Approach For The Study Of Rigid-Penetrator’S Impact Problems, Mario Buchely, Alejandro Marañon

Materials Science and Engineering Faculty Research & Creative Works

In recent years, Spherical Cavity Expansion (SCE) theory has been extensively utilized to model dynamic deformation processes related to indentation and penetration problems in many fields. In this review, the SCE theory is introduced by explaining the different mathematical features of this theory, its solution, and a potential application to model the penetration of a rigid penetrator into a deformable target. First, a chronologically literature review of the most common models used to study this kind of penetration problems is introduced, focusing on the SCE theory. Then, the engineering model of penetration is presented using the SCE approach. The model …

In-Service Performance Evaluation Of Concrete Sloped End Treatments In Iowa, Jessica Lingenfelter

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Sloped end treatments were historically developed as low-cost, low-maintenance end treatments for rigid features like concrete barriers and bridge rails. Crash testing indicated that sloped end treatments are associated with significant instability for impacting vehicles. However, the in-service performance of these features has not been evaluated. An in-service performance evaluation (ISPE) was performed to evaluate vehicle crashes with sloped end treatments in Iowa between 2008 and 2017. Researchers generated a geographic inventory of sloped end treatment locations, reviewed crash narratives and scene diagrams for crashes near these sloped end treatments, and calculated an estimated crash rate and crash cost for …

Materials-Processing Relationships For Metal Fused Filament Fabrication Of Ti-6al-4v Alloy., Paramjot Singh

Electronic Theses and Dissertations

Additive manufacturing (AM) is at the mainstream to cater the needs for rapid tooling and small-scale part production. The metal AM of complex geometries is widely accepted and promoted in the industry. While several metal AM technologies exist and are matured to a level where expectation in terms of design and properties are possible to realize. But the metal AM suffers from the heavy expense to acquire equipment, isotropic property challenges, and potential hazards to work with loose reactive metal powder. With this motivation, the dissertation aims to develop the fundamental aspects to print metal parts with bound Ti-6Al-4V powder …

Selective Laser Melting 17-4 Ph Stainless Steel And The Effect Of Varied Thermal Treatments On Fatigue Behavior., Sean Daniel Dobson

Electronic Theses and Dissertations

Fatigue failure is the leading source of loss in industry. In order for new means of manufacturing to move towards mainstream use a complete understanding of material and mechanical behavior must be gained. This endeavor seeks to aide in that task by observing the fatigue behavior of selective laser melting (SLM) additive manufacturing (AM) specimens and the effect of differing thermal treatment conditions for an optimized AM process. Stainless steel 17-4 PH specimens were fabricated using SLM AM and thermally treated to three conditions: as-built, solutionized and hardened, and direct hardened. These specimens were characterized for material (powder quality, density, …

Investigation On The Morphology Of Charge-Transfer Complexes In Low Density Polyethylene, Wade Korf

Master's Theses

Fillers are used ubiquitously throughout the fields of polymer and material science to overcome many inherent limitations to polymeric materials (i.e. poor stiffness or strength) and to expand their potential applications. There is a need to develop controllable particle architectures to better understand fundamental structure-property relationships in particle reinforced polymer composites. Charge-transfer complexes (CTCs) can assemble in situ into various needle and dendritic shapes via simple fabrication processes and at low loading levels. In this study, the effect of tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) CTC crystallites of various shapes and sizes on composite mechanical properties was investigated in an LDPE …

Effects Of Polytetrafluoroethylenemicro–Particles On Mechanical Andtribological Properties Of Glass Fiberreinforced Polyoxymethylene, Kunnan Singh Jasbir Singh

Student Works (2020-2029)

Reinforcing polyoxymethylene (POM) with glass fibers (GF) enhances its mechanical properties, but at the expense of tribological performance. Formation of a transfer film to facilitate tribo–contact is compromised due to the abrasiveness of GF. As a solid lubricant, for example, polytetrafluoroethylene (PTFE) significantly improves friction and wear resistance. The effects of chemically etched PTFE micro–particles on the fiber– matrix interface of POM/GF/PTFE composites have not been systematically characterized. This research investigated the effects of PTFE micro–particles on mechanical and tribological properties of POM/GF/PTFE composites. Since PTFE is immiscible with most polymers, the surface was etched using sodium naphthalene salt dissolved …

Selfsame Epoxide-Amine Microparticle Systems: Investigation Of Crosslink Density, John J. Peyrefitte

Honors Theses

Epoxide-amine matrix materials containing microparticles with the same chemical composition provide a model system to study interphase formation in highly crosslinked epoxide-amine matrix materials. The epoxide monomer was varied between three different monomer systems to study the model system’s relationship with crosslink density. The same amine monomer, cure procedure, and stoichiometric ratio of epoxide and amine groups were used to prepare each type of microparticle and matrix material. The differences in the epoxide monomer structure affected the crosslink density of the unmodified matrix material, which was concluded to influence the effect of microparticle presence on crosslink density. For the unmodified …

Size-Dependent Inhibitory Effects Of Antibiotic Nanocarriers On Filamentation Of E. Coli, Preeyaporn Songkiatisak, Feng Ding, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Multidrug membrane transporters exist in both prokaryotic and eukaryotic cells and cause multidrug resistance (MDR), which results in an urgent need for new and more effective therapeutic agents. In this study, we used three different sized antibiotic nanocarriers to study their mode of action and their size-dependent inhibitory effects against Escherichia coli (E. coli). Antibiotic nanocarriers (AgMUNH–Oflx NPs) with 8.6 × 10², 9.4 × 10³ and 6.5 × 10⁵ Oflx molecules per nanoparticle (NP) were prepared by functionalizing Ag NPs (2.4 ± 0.7, 13.0 ± 3.1 and 92.6 ± 4.4 nm) with a monolayer …

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. …

Development Of A Novel Vehicle Guidance System: Vehicle Risk Mitigation And Control, Michael Sweigard

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Over a half of fatal vehicular crashes occur due to vehicles leaving their designated travel lane and entering other lanes or leaving the roadway. Lane departure accidents also result in billions of dollars in cost to society. Recent vehicle technology research into driver assistance and vehicle autonomy has developed to assume various driving tasks. However, these systems are do not work for all roads and travel conditions. The purpose of this research study was to begin the development a novel vehicle guidance approach, specifically studying how the vehicle interacts with the system to detect departures and control the vehicle

A …

Syntheses And Properties Of Ta5+ Doped Li7La3Zr2O12, Feng-Feng Peng, Shi-You Li, Tong-Tong Geng, Chun-Lei Li, Shuang-Wei Zeng

Journal of Electrochemistry

The tantalum ion (Ta ⁵⁺) doped garnet-type inorganic solid electrolyte Ta-LLZO was prepared by solid state reaction, and the effect of doping amount on the properties of the materials was investigated. The materials were characterized by X-ray diffraction (XRD), field emission electron scanning microscopy (FESEM) and electrochemical impedance spectroscopy (EIS). And the cycle stability was tested by assembly of LiFePO₄//LLZTO//Li all solid lithium battery. The results show that with the increase of Ta ⁵⁺ doping amount, the material appeared to form a single cubic phase structure. When the Ta ⁵⁺ doping content became 14.09wt.%, x=0.3, the …

Preparation And Characterization Of Cathode Supported Solid Oxide Fuel Cell, Xiao-Nan Bao, Guang-Jun Zhang, Shao-Rong Wang

Journal of Electrochemistry

A site deficient (La_0.8Sr_0.2)_0.95MnO₃ (LSM95) powder was synthesized by solid state reaction as a cathode material. The commercial Zr_0.9Sc_0.1SO_1.95 (SSZ) was selected as an electrolyte material and La_0.8Sr_0.2Cr_0.5Mn_0.5O₃- (LSCrM) was synthesized by sol-gel method as an anode material. Accordingly, single cells of LSCrM-CeO₂|SSZ|3YSZ-LSM95 were prepared by tape casting, sintering and impregnation. The single cell test results for LSCrM-CeO₂|SSZ|3YSZ-LSM95 with 0.11 g·cm ^-2 CeO₂ and using CH₄ as a fuel showed the power …

Research Progress Of Fuel Electrode In Oxide-Ion Conducting Solid Oxide Electrolysers, Ling-Ting Ye, Kui Xie

Journal of Electrochemistry

Solid oxide electrolysers are now attracting much more attentions because they can efficiently produce fuels by electrolyzing H₂O/CO₂. In this paper, a comprehensive introduction to the recent progress in the development of fuel electrode (cathode) materials is provided. The advantages, disadvantages and development trend towards various cathode materials are pointed out. The key scientific and technological problems in this field are emphasized.

Perovskite Catalysts For Fuel Reforming In Sofc:A Review And Perspective, Tong Wei, Jian Li, Li-Chao Jia, Bo Chi, Jian Pu

Journal of Electrochemistry

Solid oxide fuel cell (SOFC) is a generating device by electrochemical reaction to transfer the chemical energy of fossil fuels (coal, oil and gas, etc.), the biomass fuel or other hydrocarbon fuels directly into electricity with higher energy conversion efficiency and lower pollution, which is recognized to be efficient green energy technology in the 21st century. However, when hydrocarbons are directly used as fuel, carbon deposition is easy to occur in nickel-based anode, thus, losing electrochemical catalytic activity. Fuel pre-reforming on the outside of the anode is an effective solution, which strongly relies on highly efficient and stable reforming catalysts. …

Construction And Electrochemical Performance Of Garnet-Type Solid Electrolyte/Al-Li Alloy Interface, Jia-Lin Ma, Hong-Chun Wang, Zheng-Liang Gong, Yong Yang

Journal of Electrochemistry

Garnet-type solid electrolyte is a newly developed Li ion conductor and promising in the application of all-solid-state batteries. However, Garnet is incompatible with Li anode, which restricts the application of Garnet-type solid batteries. In order to improve the contact between Garnet-type solid electrolyte and Li electrode, a composite anode which contains Al-Li alloy (Al₄Li₉) was prepared as an electrode. Al-Li alloy has many advantages such as easy preparation, low cost, simple post-treatment and high capacity. Garnet-type Li_6.5La₃Zr_1.75W_0.25O₁₂ (LLZWO) was synthesized via solid-state reaction. Garnet solid electrolyte has …

Evaluation And Update Of Mash Test Vehicles, Kellon B. Ronspies

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The Manual for Assessing Safety Hardware (MASH) requires full-scale crash testing of roadside features using worst practical impact conditions. Vehicle selection for full-scale crash testing is intended to be representative of the contemporary passenger vehicle fleet. Researchers at the Midwest Roadside Safety Facility (MwRSF) investigated attributes of passenger vehicle sales to determine if the vehicle selection criteria shown in MASH should be revised to accommodate changes in the vehicle fleet. A methodology was considered to affordably re-analyze the vehicle fleet when necessary to ensure MASH vehicle selection criteria are reflective of vehicles currently on roadways.

Representative vehicles were documented using …