Materials Science and Engineering Commons^™

In Situ Electric-Field Study Of Surface Effects In Domain Engineered Pb(In1/2nb1/2)O3-Pb(Mg1/3nb2/3)O3-Pbtio3 Relaxor Crystals By Grazing Incidence Diffraction, Markys G. Cain, Margo Staruch, Paul Thompson, Christopher Lucas, Didier Wermeille, Yves Kayser, Burkhard Beckhoff, Samuel Lofland, Peter Finkel

College of Science & Mathematics Departmental Research

In this work, we present a grazing incidence X-ray diffraction study of the surface of a 0.24Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) [011] poled rhombohedral single crystal. The near surface microstructure (the top several tens to hundreds of unit cells) was measured in situ under an applied electric field. The strains calculated from the change in lattice parameters have been compared to the macroscopic strain measured with a strain gauge affixed to the sample surface. The depth dependence of the electrostrain at the crystal surface was investigated as a function of temperature. The analysis revealed hidden sweet spots featuring unusually high strains that were …

Effect Of Nanofiller Coating And Loading On Facial Elastomer Physical Properties, Rahmi K. Aulia

Theses & Dissertations

Current materials used for facial prostheses are far from being desirable, and improved properties with “skin-like” feel are needed. This study evaluates property changes induced by sequential additions of uncoated and hydrophobic-coated nano-SiO₂ to polydimethylsiloxane (PDMS) and compares them with those measured for conventional submicron SiO₂-filled materials. Each filler type was sequentially added to vinyl-terminated PDMS at 0%, 0.5%, 5%, 10%, and 15% by weight. Tensile, tear, Durometer hardness, translucency and viscoelastic properties were evaluated, with hardness and translucency also evaluated following 3000 hours of outdoor weathering. Results demonstrated that 15% coated nano-SiO₂-filled PDMS materials …

A Brief Bibliometric Survey On Circularly Polarized Antennas For Mobile Communication, Aniket Gunjal, Abhaya Pal Singh

Library Philosophy and Practice (e-journal)

This paper presents a database review on “Circularly Polarized Antennas for Mobile Communication” as it is the emerging technique used by mobile service provider because of having benefits over other types of antennas available.The polarization purity is now the major issue. In some cases due to cross polarization issue the antenna signal is cancelled at receiver side.So, it is necessary to have circularly polarized antenna to avoid this polarization issue because of change in phase of signal. The change in phase of signal is due to striking of wave on the obstacles and it slightly tilted from its direction causes …

Plastic Recycling In Additive Manufacturing: A Systematic Literature Review And Opportunities For The Circular Economy, Fabio A. Cruz Sanchez, Hakim Boudaoud, Mauricio Camargo, Joshua M. Pearce

Michigan Tech Publications, Part 1

The rapid technical evolution of additive manufacturing (AM) enables a new path to a circular economy using distributed recycling and production. This concept of Distributed Recycling via Additive Manufacturing (DRAM) is related to the use of recycled materials by means of mechanical recycling process in the 3D printing process chain. This paper aims to examine the current advances on thermoplastic recycling processes via additive manufacturing technologies. After proposing a closed recycling global chain for DRAM, a systematic literature review including 92 papers from 2009 to 2019 was performed using the scopus, web of science and springer databases. This work examines …

The Influence Of Surface Types Towards Run-Off Water In Urban Park, Febby Andini

International Programs

Pavements in Alun Kapuas Park constribute 63 of run off water over the capacity of the soil to infiltrate. This water will potentially causes the flooding and puddling issues.

The Applications Of Auxetic Material, Faizal Arifurrahman

International Programs

To date, increasing structural efficiency has become a main objective in material science and engineering. One focus is an auxetic material with a unique characteristic obtained by fabricating cellular forms. With its higher strength-to-weight ratio, auxetic is becoming popular in the real-world to produce products that are light but more durable. This study examines potential application of auxetic compared to that of conventional material.

Artificial Neural Network Discovery Of A Switchable Metasurface Reflector, J. R. Thompson, J. A. Burrow, P. J. Shah, Jonathan E. Slagle, E. S. Harper, A. Van Rynbach, I. Agha, M. S. Mills

Student Publications

Optical materials engineered to dynamically and selectively manipulate electromagnetic waves are essential to the future of modern optical systems. In this paper, we simulate various metasurface configurations consisting of periodic 1D bars or 2D pillars made of the ternary phase change material Ge2Sb2Te5 (GST). Dynamic switching behavior in reflectance is exploited due to a drastic refractive index change between the crystalline and amorphous states of GST. Selectivity in the reflection and transmission spectra is manipulated by tailoring the geometrical parameters of the metasurface. Due to the immense number of possible metasurface configurations, we train deep neural networks capable of exploring …

Homogenization Of Composite And Cellular Materials Incorporating Microstructure And Surface Energy Effects, Ahmad Gad

Mechanical Engineering Research Theses and Dissertations

In the last few decades, the popularity of composite and cellular materials has rapidly increased through their widespread applications in multiple engineering fields including aerospace, automotive, civil and biomedical. However, to a large extent, the success of their practical applications depends on our ability to predict their mechanical behavior by using high-fidelity mechanics models.

Micromechanical modeling of composite and cellular materials is a challenging task due to the heterogeneous nature of such materials and the interactions among various constituent phases at the microscopic level, which result in non-homogeneous deformation, strain and stress fields. Therefore, it is necessary to develop simple …

Maleic Anhydride Compatibilized Peach Waste As Filler In Polypropylene And High Density Polyethylene Biocomposites, Caralyn Wong, Stephanie Jung, Joongmin Shin, Ajay Kathuria

Master's Theses

It is estimated that roughly 103, 515 tons of peach waste is produced annually in the US. The majority of the waste is disposed of in landfills, which contributes to climate change as they release 93 million metric tons of CO₂ equivalent. Peach waste principally consists of remaining stone and seed after flesh removal. The agro-waste includes both cellulose and lignin, which can be utilized as a filler in plastic packaging to reduce carbon footprints and material cost. The objectives of this research are (1) to develop peach flour (PF)-filled biocomposites with a polyolefin matrix using maleic anhydride-g-high density …

Synthesis And Characterization Of Cobalt-Based Magnetic Nanostructures, Jacob Elkins

Material Science and Engineering Theses - Archive

Co is an attractive element in the development of nanostructured magnetic materials due to its relatively high moment (1.72-1.75 µB) and strong exchange and spin-orbit interactions, and many of these materials have potential in applications such as data recording media, hyperthermia treatments, and nanostructured permanent magnets. In this thesis, magnetic nanostructures of CoFe2O4, Co, and CoNi with controlled size, shape, composition, and crystal structure are synthesized via bottom-up wet chemical methods and their magnetic properties are systematically characterized. Additionally, nanocomposites of exchange-coupled FeCo/CoFe2O4 and Co/FeCo core-shell nanostructures with enhanced magnetizations are prepared and investigated. In order to understand the prominent …

Study Of Interdiffusion And Growth Of Intermetallic Compounds In Bimetallic Layers Of Alpha Brass And Al-Mg Alloy, Ratan Kota

Material Science and Engineering Theses - Archive

This work aims to study the formation of Inter Metallic Compounds (IMC’s) and their growth rate in Brass and Al-Mg alloy. This diffusion couple consists of four elements Aluminum, Copper, Zinc and Magnesium. Aluminum and Copper are major diffusing elements. Brass-Aluminum bimetal is an advanced structural material and used as a cladding material. This bimetal is produced by cold roll bonding and is mechanically bonded. To increase the adhesive strength of these bimetal layers, the sample is subjected to heat treatment which leads to the formation of Inter Metallic Compounds (IMC). Heat treatments are generally done above the recrystallization temperature …

An Investigation On The Corrosion Inhibition Of Brazing Cu-Ag Alloy, Hooman Rahmani

Material Science and Engineering Dissertations - Archive

Adsorption and inhibition behavior of 1,2,3-benzotriazole (BTA) and 2,5-dimercapto-1,3,4-thiadiazole (DMTD) on brazing Cu-Ag alloy was studied in deionized water using corrosion potential measurement, potentiodynamic polarization, adsorption isotherm investigation, X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS). Pure Ag and pure Cu specimens were included to investigate the mere effect each component has on the alloy’s behavior along with a high copper alloy for comparison purposes. The electrochemical responses show that BTA shifts the corrosion potential of Cu to the noble direction but has the opposite effect for Ag and a mixed behavior for the Cu-Ag alloys. However, DMTD in …

Study Of New Transistor Architecture With Energy Filtering, Nnaemeka Mcdonald Eluagu

Material Science and Engineering Theses - Archive

The thermodynamic limit of the subthreshold slope to 60mV/decade at 300K forces MOSFET devices to use high supply voltages (> 0.5V) and therefore dissipate a lot of energy. This physical limitation of transistors is a direct consequence of thermal excitation of electrons. This study investigates a new transistor architecture capable of suppressing thermally excited electrons using a quantum well as an energy filter. The energy filter consists of a 2nm SiO2 tunneling barrier and a 2nm Quantum Well (QW) layer of Cr2O3 sandwiched between Ni electrodes and a channel of Si. Transistors having this QW energy filter have been fabricated …

Investigation Of High-Temperature Oxidation Resistance Mechanism Of Ceramic Coatings Via Microstructure Analysis, Yi Shen

Material Science and Engineering Dissertations - Archive

Recent developments of ceramic coatings deposited using magnetron reactive sputtering show that these films exhibited superior high-temperature oxidation resistance along with other desirable properties such as high hardness, optical transparency and good electrical conductivity. Detailed microstructure study of these films annealed to high temperatures using transmission electron microscopy (TEM) is deemed necessary as it provides an intuitive vision on the behavior of the materials at elevated temperature, which is essential to further improve their high-temperature oxidation resistance. In this study, Hf-B-Si-C-N films with various compositions that were annealed to various temperatures in both helium and air were subjected to detailed …

The Structural And Magnetic Properties Of Nio/Mn(Ni)-Oxide Magnetic Heterostructured Nanocrystals Synthesized Under Varying Ph Values, Abdullah Al Shafe

Graduate Theses/Dissertations

The role of pH on the structural, morphological, and magnetic properties of hydrothermally synthesized NiO-based magnetic heterostructured nanocrystals (MHNCs) is investigated. The NiO nanocrystals were synthesized using a two-step thermal decomposition process whereas the deposition of the surrounding Mn-based phases was accomplished by hydrothermal means at pH values ranging from 2.4 to 7.0. The resulting heterostructured nanocrystals consist of inverted AFM-FiM NiO/±Mn_xNi_1-xO/±Mn₃O₄ bimagnetic/trimagnetic systems. A complete characterization of the MHNCs was carried using XRD, TEM, EDS, MPMS magnetometry and XPS analysis. Structural investigations revealed predominantly faceted MHNCs ranging in size from 24-30 nm …

Investigation Of Various Techniques For Controlled Void Formation In Fiberglass/Epoxy Composites, Donald A. Klosterman, Charles Browning, Issa Hakim, Kyle Lach

Chemical and Materials Engineering Faculty Publications

The effect of porosity in composite materials has been studied for years due to its deleterious effects on mechanical properties, especially matrix dominated properties. Currently there is an increasing use of composites in infrastructure worldwide, for example bridge components, residential and building structures, marine structures such as piers and docks, and large industrial chemical tanks. Most of these applications use fiberglass composites. Unfortunately, most of the published literature has focused on carbon fiber composites, in which fiber diameter and gas-fiber interactions are different than fiberglass composites. Therefore, the present study was undertaken to revisit the effect of porosity but specifically …

Aqueous Redox Flow Batteries With Boron Doped Diamond As An Electrode., Alex M. Bates

Electronic Theses and Dissertations

As the interest and implementation of renewable energy accelerates, so does that of grid energy storage. It is widely believed that a cost-effective energy storage technology will bring about the proliferation of renewable energy. Redox flow battery (RFB) technology represents a promising solution to cost-effective grid energy storage. Compared to other technologies, RFBs have a long lifetime, high efficiency, are non-flammable, significantly reduce cost, and separately scale power and energy. The separation of power and energy enables increased energy capacity by simply adding electrolyte volume. Of the challenges facing RFB technology, one readily apparent is the cost of the active …

Hydrothermal Reaction Synthesis And Characterization Of Zns:Ag Scintillator, Yuchen Shao

All Theses

Thisworkaims at the development of a reactive ultrafiltration membrane scintillator for rapid activity determination and isotopic quantification of waterborne special nuclear materials (SNMs) based on ZnS:Ag. The effects of the pH of the precursor solution on ZnS:Ag synthesized under various conditions of temperature and time by the hydrothermal reaction synthesis method (200℃ for 6 hours, pH from 1 to 12; 100℃ for 2 hours, pH from 7 to 12;60℃ for 6 hours, pH from 7 to 12) were investigated. Samples were characterized on their structure, morphology and luminescence by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), photoluminescence (PL) …

Single Molecule Super-Resolution Microscopy Study On The Precision With Which Dna Nanostructures Can Orient Fluorescent Dyes, Brett Michael Ward

Boise State University Theses and Dissertations

DNA nanotechnology enables the rapid, programmable self-assembly of novel structures and devices at the nanoscale. Utilizing the simplicity of Watson-Crick base pairing, DNA nanostructures are capable of assembling a variety of nanoparticles in arbitrary configurations with relative ease. Several emerging opto-electronic systems require a high degree of control of both the position and orientation of component fluorescent molecules, and while DNA nanostructures have demonstrated these capabilities, the precision with which DNA can orient fluorescent molecules is not well understood. Determining these bounds is critical in establishing the viability of DNA nanotechnology as a method of assembling fluorescent molecular networks.

In …

Mxenes As Flow Electrodes For Capacitive Deionization Of Wastewater, Naqsh E. Mansoor

Boise State University Theses and Dissertations

The energy-water nexus poses an integrated research challenge, while opening up an opportunity space for the development of energy efficient technologies for water remediation. Capacitive Deionization (CDI) is an upcoming reclamation technology that uses a small applied voltage applied across electrodes to electrophoretically remove dissolved ionic impurities from wastewater streams. Similar to a supercapacitor, the ions are stored in the electric double layer of the electrodes. Reversing the polarity of applied voltage enables recovery of the removed ionic impurities, allowing for recycling and reuse. Simultaneous materials recovery and water reclamation makes CDI energy efficient and resource conservative, with potential to …

Ractive Md Simulation On The Formation Of Amorphous Alumina Layer Using Atomic Layer Deposition (Ald), Yuxuan Lu

Graduate Theses/Dissertations

In this study, a systematic study has been performed by using the large-scale classical reactive molecular dynamics (MD) simulations to model the Atomic Layer Deposition (ALD) processes that generated tan ultra-thin and sub-nano meter amorphous alumina. The ALD process employed both water pulse and (Trimethyl-Aluminum) TMA precursors deposited onto the surface of an aluminum wetting layer. The study varied the sizes of the substrate and the concentrations of water/hydroxide precursors with a range of operating temperature to design the most favorable configurations for the subsequent TMA precursors to add onto. The role of crystallographic orientation of the Al wetting layer …

Development Of A Cvd Assisted Pld System For Growing Novel Materials, Sinjan Majumder

Graduate Theses/Dissertations

The fundamental step for development of novel materials like semiconductors involves stacking of layers of thin films of materials with desired properties on a particular substrate. In order to study the properties of these materials for research purposes in the laboratory, development of a clean fabrication technique is essential. PLD is a technique employed for growing thin films using laser ablation of a target material. CVD is an alternate method used to deposit solid materials from a gaseous phase. However, combining these two techniques can enhance plume, gas and laser interaction to facilitate the growth of novel materials with new …

Performance Of Pld Grown Zno Thin Film As A Thin Film Transistor, Shahidul Asif

Graduate Theses/Dissertations

The performance of ZnO thin film (grown in different parameters) as a thin film transistor (TFT) is the focus of this study. ZnO is renowned for being n-type semiconductor naturally which was utilized in fabricating a thin film transistor here. This thesis is compared the performance of ZnO thin film transistor by growing the thin film using pulsed laser deposition (PLD) on two slightly different substrates at different temperatures in an optimal 0.1 milli bar oxygen pressure which was later analyzed using other material characterization methods. The substrates were both Si (100) but had different resistivity due to different amount …

Material Design, Processing, And Engineering Requirements For Magnetic Shape Memory Devices, Andrew Armstrong

Boise State University Theses and Dissertations

For magnetic shape memory (MSM) alloys, a magnetic field stimulates a shape change. We use the shape change to build devices such as micro-actuators, sensors, and microfluidic pumps. Currently, (as a novel technology,) devices suffer from some material and magnetic driver shortcomings. Here we address the issues related to operating temperature, repeatability, failure, and magnetic driver development. To increase the operating temperature of the MSM material, we alloyed Fe and Cu to Ni-Mn-Ga. We showed that the element-specific contribution to the valence electron density as parameter systematically determines the effect of each element on the variation of the martensite transformation …

U.S. Greenhouse Gas Emission Bottlenecks: Prioritization Of Targets For Climate Liability, Alexis Pascaris, Joshua M. Pearce

Michigan Tech Publications, Part 1

Due to market failures that allow uncompensated negative externalities from burning fossil fuels, there has been a growing call for climate change-related litigation targeting polluting companies. To determine the most intensive carbon dioxide (CO₂)-emitting facilities in order prioritize liability for climate lawsuits, and risk mitigation strategies for identified companies as well as their insurers and investors, two methods are compared: (1) the conventional point-source method and (2) the proposed bottleneck method, which considers all emissions that a facility enables rather than only what it emits. Results indicate that the top ten CO₂ emission bottlenecks in the U.S. …

Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim

Mechanical Engineering

Formula SAE is a collegiate competition hosted by SAE International with the primary goal being to design, manufacture, and race an open wheel race car. The Cal Poly Racing Formula SAE team strives for improvement every race season and has remained competitive as a result. The 2019-2020 management team determined that further research and development towards the chassis would yield the greatest performance benefit for future seasons, as the previous chassis platform limited packaging and mounting options for vehicle subsystems which interfaced with the chassis.

A redesign of the Cal Poly Racing Formula SAE team’s carbon fiber reinforced polymer monocoque …

Production And Characterization Of Uranium Sol Gel Surrogates Produced With Cerium Acetate And Cerium Nitrate, Matthew Brett Alford

All Dissertations

For the production of ceramic microspheres for future space travel, new methods of processing must be explored. The sol gel method proves promising for the production of uranium-based ceramic microspheres that are consistent enough in size and shape for such an application. A process for producing these microspheres has already been established, but there are avenues for improvement.

Handling of radioactive material like uranium is not always possible or warranted. As such, a non-radioactive surrogate that greatly resembles the processing of its actual radioactive counterpart. Herein this work a cerium-based surrogate is developed to closely resemble an already established process …

Synthesis And Characterization Of Bimetallic Gold-Silver (Au-Ag) Nanocatalyst Via Seed Colloid Technique, Berahim Nurafaliana

Student Works (2020-2029)

In the present study, unique catalysts of monometallic gold (Au), silver (Ag) and bimetallic gold-silver (Au-Ag) nanoparticles (NPs) were prepared with different size or diameters by the citrate-thermal reduction and the seed colloidal techniques, respectively. The catalytic nanoparticles were characterized by various advanced analytical techniques such as Ultraviolet-visible spectroscopy (UV-vis), zeta potential, electron dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), High-angle annular dark-field (HAADF) scanning transmission-electron microscopy (STEM) imaging and the energy dispersive spectroscopy (EDS) elemental mapping. The catalytic performance of the nanoparticles were ascertained through the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in …

Comparison Of Pressure-Assist Silver Sintering To Tin Silver Solder Alloy As Die Attach Material In High Power Semiconductor, Tolentino Erik Nino

Student Works (2020-2029)

The research is focused on pressure-assisted silver sintering material that is compared to tin silver solder alloy paste as used in power electronics. Material characterization, electrical tests, and reliability tests were conducted in the experiment. After drying process, it was observed that the Ag sintering paste height was reduced to approximately 40 percent. Die attach shear test showed that the average reading is about from 200 to 600 grams which are already enough to hold the dice before proceeding to the pressure sintering process. X-ray revealed that the void percent for SnAg paste sample is about 1.5 percent while pressure-assist …

Synthesis And Characterization Of Self-Cleaning Hydrophobic Organic Coating, Abdul Jaafar Amirul Syafiq

Student Works (2020-2029)

Three self-cleaning coating systems namely Polydimethylsiloxane (PDMS)/Sylgard, PDMS/3-Aminopropyltriethoxysilane (APTES) (tagged as A1) and A1 blended with nano-Calcium Carbonate (CaCO3) have been synthesised on glass substrates via dip-coating and spray-coating techniques. All of the prepared coatings were dried under ambient condition before being subjected to characterisations and testing(s). The effect of various weight percentages of Sylgard resin that are 5wt.% (S1 coating), 10wt.% (S2 coating), 15wt.% (S3 coating), and 20 wt.% (S4 coating) on the hydrophobicity, self-cleaning property, anti-fog performance and mechanical property of PDMS/Sylgard coating have been discussed in the first section of this thesis. The PDMS/Sylgard coated glass substrates …