Materials Science and Engineering Commons^™

Recovery Of Rare Earth Elements (Rees) From Coal Mine Drainage Sludge Leachate, Panpan Ren

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is the primary cause of aquatic habitat loss in the Appalachian Coal Basin and many other mining districts across the U.S. and the world. The objective of this work is to develop a cost-effective and environmentally benign process to treat and recover Rare Earth Elements (REEs) from AMD. Solvent extraction (SX) is one effective way to turn AMD into a commercially viable feedstock for rare earth production.

In this work, SX experiments were conducted on Y-Ca-Mg-Al-HDEHP-n-heptane-HNO3-H2O system to simulate AMD treatment for Yttrium recovery by changing four parameters: pH values, concentration ratio of Yttrium (Y) over …

Engineering Plasmonic Nanostructures For Light Management And Sensing, Sujan Phani Kumar Kasani

Graduate Theses, Dissertations, and Problem Reports (ETD)

The two major global problems are to provide health safety and to meet energy demands for ever growing population on a large scale. The study of light interaction with nanostructures has shown a promising solution in improving the fields of bio-sensor and solar energy devices which addresses above mentioned two major global problems. Nanostructures have tunable physicochemical properties such as light absorption, electrical and thermal properties unlike bulk materials, which gives an advantage in applications like bio-sensing and energy harvesting devices. The development of nanofabrication techniques along with the discovery of Surface Enhanced Raman Scattering (SERS) and Plasmon Enhanced Fluorescence …

Towards Sustainable Production Of Chemicals And Fuels From The Fast Pyrolysis Of Waste Polyolefin Plastics, Ulises Gracida Alvarez

Dissertations, Master's Theses and Master's Reports

The increasing amount of plastic waste (PW) generation has become an important concern due to the leveled-off recycling rates. Therefore, governmental agencies around the world, including state governments in the United States, have proposed initiatives to minimize the amount of PW that is landfilled and encourage recycling or energy recovery. Circular economy is a strategy that attempts on reusing PW to produce new polymers while avoiding its disposal and the use of virgin material. Chemical recycling raises an interesting technology prospect due to the potential reduction of pollutant emissions and the establishment of a circular economy through the production of …

Mse Annual Report 2019, Department Of Materials Science And Engineering, Michigan Technological University

Department of Materials Science and Engineering Annual Reports

Table of Contents

• Faculty and Staff News
• Faculty Research
• Student News
• Alumni News
• By the Numbers
• K-12 Outreach

Direct Polymer Grafting As A Method Of Maintaining The Mechanical Properties Of Cellulose Nanocrystals In The Presence Of Moisture, Mary Elizabeth Breen-Lyles

Graduate Research Theses & Dissertations

Cellulose nanocrystals (CNCs) are a distinctive nanomaterial derived from cellulose, the most abundant natural polymer on Earth, and the primary reinforcing structural component of cellulose fibrils found within the plant cell wall. These nanocrystals exhibit mechanical properties comparable to synthetic aramid fibers but are advantageous as they are biodegradable, renewable, and can be produced sustainably as they are predominantly extracted from naturally occurring cellulosic materials. These qualities make it a sustainable, highly renewable and environmentally friendly material to be used in place of synthetic materials in a variety of applications. With their high surface area to volume ratio, low level …

Studying The Effect Of Vacancies On The Thermal Conductivity Of Metal-Coated Carbon Nanotubes Using Molecular Dynamics Atomistic Simulations, Ravindra Sunil Dhumal

Graduate Research Theses & Dissertations

Breakthroughs in nanotechnology have made it possible for the size of electronic gadgets to be scaled down to micro/nano level. What follows however, is the side effect of high power densities and overheating as the heat dissipation is restricted to very small surface area. Thus, the need of an effective thermal management system is central to these developments. One way to counter this problem is to use Thermal Interface Materials (TIMs) which promote heat transfer between heat source and sink.

Owing to their high thermal conductivity (up to 6000 W/mK), Carbon Nanotubes (CNTs) are thought of as strong candidates for …

The Study Of Scandate Cathode And Its Characterization Under Various Stages Of Processing, Xiaomeng Zhang

Theses and Dissertations--Chemical and Materials Engineering

Scandate cathode under various processing stages: scandia nano-powder, tungsten scandia mix powder, sintered and impregnated pellets, were characterized with techniques that included electron microscopy, EDS, XPS, and work function measurements. The size and shape uniformity of nano-scale scandia particles changed from round to square and polyhedron during heat treatment. Reduction in size and improvement in size uniformity as heat treating temperature increased were observed. When determining the highest Sc coverage, three assessment methods were used and with their combined results, it was concluded that set VII had the highest Sc at%. In the sintered pellets, it was observed with SEM …

Biomass-Derived Activated Carbons For Electrical Double Layer Supercapacitors: Performance And Stress Effect, Wenxin Cao

Theses and Dissertations--Chemical and Materials Engineering

The vigorous development of human civilization has significantly increased the energy consumption in recent years. There is a great need to use renewable energy sources to substitute the depleting traditional fossil fuels, such as crude oil, natural gas and coal. The development of low-cost and high-performance energy storage devices (ESDs) and systems have drawn great attention due to their feasibility as backup power supply and their applications in portable electronics and electric vehicles. Supercapacitors are among the most important ESDs because of their long charging-discharging cycle life, high power capability and a large operating temperature range. In this thesis, high-performance …

Mechanical Properties And Degradation Of High Capacity Battery Electrodes: Fundamental Understanding And Coping Strategies, Yikai Wang

Theses and Dissertations--Chemical and Materials Engineering

Rechargeable lithium ion and lithium (Li) metal batteries with high energy density and stability are in high demand for the development of electric vehicles and smart grids. Intensive efforts have been devoted to developing high capacity battery electrodes. However, the known high capacity electrode materials experience fast capacity fading and have limited cycle life due to electromechanical degradations, such as fracture of Si-based electrodes and dendrite growth in Li metal electrodes. A fundamental understanding of electromechanical degradation mechanisms of high capacity electrodes will provide insights into strategies for improving their electrochemical performance. Thus, this dissertation focuses on mechanical properties, microstructure …

Nanoharvesting And Delivery Of Bioactive Materials Using Engineered Silica Nanoparticles, Md Arif Khan

Theses and Dissertations--Chemical and Materials Engineering

Mesoporous silica nanoparticles (MSNPs) possess large surface areas and ample pore space that can be readily modified with specific functional groups for targeted binding of bioactive materials to be transported through cellular barriers. Engineered silica nanoparticles (ESNP) have been used extensively to deliver bio-active materials to target intracellular sites, including as non-viral vectors for nucleic acid (DNA/RNA) delivery such as for siRNA induced interference. The reverse process guided by the same principles is called “nanoharvesting”, where valuable biomolecules are carried out and separated from living and functioning organisms using nano-carriers. This dissertation focuses on ESNP design principles for both applications. …

The Fabrication And Characterization Of Metal Oxide Nanoparticles Employed In Environmental Toxicity And Polymeric Nanocomposite Applications, Matthew Logan Hancock

Theses and Dissertations--Chemical and Materials Engineering

Ceria (cerium oxide) nanomaterials, or nanoceria, have commercial catalysis and energy storage applications. The cerium atoms on the surface of nanoceria can store or release oxygen, cycling between Ce³⁺ and Ce⁴⁺, and can therefore act as a therapeutic to relieve oxidative stress within living systems. Nanoceria dissolution is present in acidic environments in vivo. In order to accurately define the fate of nanoceria in vivo, nanoceria dissolution or stabilization is observed in vitro using acidic aqueous environments.

Nanoceria stabilization is a known problem even during its synthesis; in fact, a carboxylic acid, citric acid, is …

Magnetotransport In Zrte5 Crystals, Maksim Andreevich Sultanov

Graduate Research Theses & Dissertations

ZrTe5 is a topological material that is predicted to have a strain or temperature induced phase transition from a topological insulator state into a Weyl/Dirac semimetal state. In this study I find that there is insufficient evidence to support the claims for the existence of such a phase transition. I performed magnetoresistivity measurements using a Quantum Design Physical Properties Measurement System (PPMS) to measure the transverse and longitudinal resistivities at various temperatures and different strengths and orientations of the magnetic field. The measurement results were analyzed using OriginPro to determine the carrier mobility and density and to determine the temperature …

Improving Base Metal Electrowinning, Charles Ebenezer Abbey

Doctoral Dissertations

"In zinc electrowinning, Mn oxidizes to form MnO₂ on Pb-Ag anodes, cell walls and pipes. MnO₂ reduces anode corrosion but also leads to short circuits and maintenance issues. MnO₂ is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl^- ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl …

Chemically-Bonded Enamel-Coated Steel Pipelines For Corrosion Protection And Flow Efficiency, Liang Fan

Doctoral Dissertations

"This study is to explore and develop chemically-bonded enamel coating (200-300 um) on steel pipes, when subjected to soil and thermal environments, in order to improve the corrosion protection and safety of hazardous liquid and natural gas pipelines while reducing pressure loss. Out of five types of enamels and their various mixtures, Tomatec slurry and GP2118 powder were selected for steel pipeline applications. They were applied at approximately 810 °C to the inside surface of steel pipes in wet and electrostatic processes, respectively. The thickness and surface roughness of the enamel coating were measured using a gauge and an optical …

Freeform Extrusion Fabrication Of Advanced Ceramics And Ceramic-Based Composites, Wenbin Li

Doctoral Dissertations

"Ceramic On-Demand Extrusion (CODE) is a recently developed freeform extrusion fabrication process for producing dense ceramic components from single and multiple constituents. In this process, aqueous paste of ceramic particles with a very low binder content ( < 1 vol%) is extruded through a moving nozzle to print each layer sequentially. Once one layer is printed, it is surrounded by oil to prevent undesirable water evaporation from the perimeters of the part. The oil level is regulated just below the topmost layer of the part being fabricated. Infrared radiation is then applied to uniformly and partially dry the top layer so that the yield stress of the paste increases to avoid part deformation. By repeating the above steps, the part is printed in a layer-wise fashion, followed by post-processing. Paste extrusion precision of different extrusion mechanisms was compared and analyzed, with an auger extruder determined to be the most suitable paste extruder for the CODE system. A novel fabrication system was developed based on a motion gantry, auger extruders, and peripheral devices. Sample specimens were then produced from 3 mol% yttria stabilized zirconia using this fabrication system, and their properties, including density, flexural strength, Young's modulus, Weibull modulus, fracture toughness, and hardness were measured. The results indicated that superior mechanical properties were achieved by the CODE process among all the additive manufacturing processes. Further development was made on the CODE process to fabricate ceramic components that have external/internal features such as overhangs by using fugitive support material. Finally, ceramic composites with functionally graded materials (FGMs) were fabricated by the CODE process using a dynamic mixing device"--Abstract, page iv.

Oxide Inclusion Evolution And Factors That Influence Their Size And Morphology, Obinna M. Adaba

Doctoral Dissertations

"The evolution of oxide inclusion size distribution and the shape of the distribution during steelmaking and casting and the process variables that influence the inclusion characteristics at different stages were investigated and documented. A statistical method for transforming the 2D size distribution to their actual 3D distributions and the application of a kinetic model to determine nucleation and growth mechanisms were tested. Finally, laboratory experiments were performed to study the effects of preexisting inclusions, steel active oxygen content, and supersaturation on the size and morphology of Al₂O₃ inclusions.

The inclusion size, composition, and morphology following steel deoxidation …

Electrodeposition Of Epitaxial Metal Thin Films On Silicon For Energy Conversion And Flexible Electronics, Qingzhi Chen

Doctoral Dissertations

"This research focuses on epitaxial electrodeposition of two coinage metals: Au and Ag thin films on the silicon surface and their applications in flexible electronics and energy conversion and storage. The first paper: Photoelectrochemistry of ultrathin, semi-transparent, and catalytic gold films electrodeposited epitaxially onto n-silicon (111) describes the epitaxial electrodeposition of Au thin films on n-type Si using a simple HAuCl4 bath and the photoelectrochemical properties of the Au-Si junction barrier. The effect of the Au layer on the interfacial energetics as well as the stability of the photoelectrode as a function of the Au coverage/thickness is determined in a …

Nanomorphology Dependent Optical And Mechanical Properties Of Aerogels, Chandana Mandal

Doctoral Dissertations

"Aerogels are very low density, light weight open pore materials. A hypothesis that is under intense current investigation by the scientific community states that the mechanical properties of nanostructured polymers depend on their nanomorphology. Aerogels are nanostructured ultra-lightweight nanoporous materials with skeletal frameworks that can display a wide range of nanomorphologies. Thereby aerogels comprise a suitable platform for testing not only that hypothesis but also a wide range of other properties such as light scattering for applications, for example, in thermally insulating windows.

To study the mechanical properties of nanostructured matter as a function of nanomorphology, various shape-memory polyurethane aerogels …

Synthesis And Applications Of Ceramic (Silicon Carbide And Silicon Nitride), Metallic (Cobalt(0)) And Polymeric (Polyurethane) Aerogels, Parwani M. Rewatkar

Doctoral Dissertations

"A new method has been demonstrated for the synthesis of monolithic ceramic and purely metallic aerogels from xerogel powder compacts, and the use of polyurethane aerogels based on cyclodextrins as efficient desiccants.

I. Highly porous ( > 80%) monolithic SiC and Si₃N₄, aerogels were prepared from compressed compacts of polyurea-crosslinked silica xerogel powders. The process is time efficient as solvent-exchange through powders is fast, and energy efficient as it bypasses drying with supercritical fluids. The final ceramic objects were chemically pure, sturdy, with compressive moduli at 37 ±7 MPa and 59 ± 7 MPa, and thermal conductivities …

Polyurea Aerogels: From Nanoscopic To Macroscopic Properties, Tahereh Taghvaee

Doctoral Dissertations

"The morphology of a material is intrinsically a qualitative property and in order to relate nanomorphology to synthetic conditions, it is necessary to express nano/micro-structure quantitatively. In this context, polyurea aerogels were chosen as a model system with demonstrated potential for rich nanomorphology and being guided by a statistical Design-of-Experiments model, a large array of materials (208) with identical chemical composition, but quite different nanostructures were prepared. By reflecting upon the SEM images, it was realized that our first pre-verbal impression about a nanostructure is related to its openness and texture; the former is quantified by porosity (Π), and the …

Microstructural Evolution Of Zirconium Carbide (Zrcₓ) Ceramics Under Irradiation Conditions, Raul Florez

Doctoral Dissertations

A comprehensive understanding of the microstructural evolution of Zirconium Carbide (ZrC₂) ceramics under irradiation conditions is required for their successful implementation in advanced Gen-IV gas-cooled nuclear reactors. The research presented in this dissertation focusses on elucidating the ion and electron irradiation response of ZrC₂ ceramics. In the first part of the research, the microstructural evolution was characterized for ZrC₂ ceramics irradiated with 10 MeV Au³⁺ ions up to doses of 30 displacement per atom (dpa) at 800 ºC. Coarsening of the defective microstructure, as a function of dose, was revealed by transmission electron microscopy analysis. …

Development Of Stage-I Tempered High Strength Cast Steel For Ground Engaging Tools, Viraj Ashok Athavale

Doctoral Dissertations

"Ground Engaging Tools (GET) are the expendable replacement parts used in heavy machinery used with mining or construction equipment. GET’s protect the expensive machine components from the wear and tear found common in high-impact or high-abrasion environments. The goal of this project is to develop advanced next-generation alloy choices that outperforms the existing GET materials. A method of predicting tempered hardness of mixed microstructures was formulated. Using this model, two alloy series viz. Cr-Ni-Mo and Mn-Si-Mo-V were proposed and experimented with the goal of obtaining a high strength and impact resistant cast steel. Cast iterations of Cr-Ni-Mo alloy series were …

Three-Dimensional Nanotube Arrays For Solar Energy Harvesting And Production Of Solar Fuels, Wipula P. R. Liyanage

Doctoral Dissertations

"Over the past decade extensive research has been carried out on photovoltaic semiconductors to provide a solution towards a renewable energy future. Fabricating high-efficiency photovoltaic devices largely rely on nanostructuring the photoabsorber layers due to the ability of improving photoabsorption, photocurrent generation and transport in nanometer scale. Vertically aligned, highly uniform nanorods and nanowire arrays for solar energy conversion have been explored as potential candidates for solar energy conversion and solar-fuel generation owing to their enhanced photoconversion efficiencies.

However, controlled fabrication of nanorod and especially nanotube arrays with uniform size and shape and a pre-determined distribution density is still a …

Nanoscale Solidification Of Metals By Atomistic Simulations: From Nucleation To Nanostructural Evolution, Avik Mahata

Doctoral Dissertations

"Homogeneous nucleation during solidification in Al (fcc), Fe (bcc) and Mg (hcp) is studied by million-atom molecular dynamics (MD) utilizing the second nearest neighbor modified embedded atom method (2NN-MEAM) potentials. Spontaneous homogenous nucleation from the melt was produced without any influence of pressure, free surface effects and impurities. We also study the effect on the simulation size on homogenous nucleation and the heterogeneity in homogenous nucleation. The heterogeneity in homogenous nucleation originates from the twins, grain boundaries and short range order in the liquid during the initial stages of solidification.

To study the solid-liquid coexistence in binary Al alloys, interatomic …

On Developing A Graphitic White Iron For Metal-To-Metal Wear Systems, Jie Wan

Doctoral Dissertations

"This research addressed heat dissipation issues related to the adhesive wear observed in metal-to-metal wear systems, by developing a graphitic white iron to increase thermal diffusivity of the wear components. One of the premium materials commonly used in current metal-to-metal wear systems is Fe15Mo18Cr and field returned parts were characterized as part of this study. Failure analysis showed that white layers were formed on the wearing surface due to frictional heating and surface deformation. These white layers were extremely brittle and could be fractured easily during use, which in turn led to micro-galling defects that caused parts leakage. Increasing thermal …

Remanufacturing Of Precision Metal Components Using Additive Manufacturing Technology, Xinchang Zhang

Doctoral Dissertations

"Critical metallic components such as jet engine turbine blades and casting die/mold may be damaged after servicing for a period at harsh working environments such as elevated temperature and pressure, impact with foreign objects, wear, corrosion, and fatigue. Additive manufacturing has a promising application for the refurbishment of such high-costly parts by depositing materials at the damaged zone to restore the nominal geometry. However, several issues such as pre-processing of worn parts to assure the repairability, reconstructing the repair volume to generate a repair tool path for material deposition, and inspection of repaired parts are challenging. The current research aims …

Optical Properties Of Polymers And Their Applications, Samiha Hossain

Theses

The last decade has witnessed explosive growth in the world of photoactive polymers for a variety of applications in several sectors of the global economy. The need for efficient, reliable, and low-cost data acquisition, storage, processing, transmission, and display technologies has made it necessary for research aimed at addressing these needs. Recent accomplishments in this materials area represent exciting opportunities for major innovations in various fields. However, further work needs to be done to transfer the technology from fundamental R&D to manufacturing. The goal of this study is to provide a better understanding of the optical properties of polymers and …

Scanning Probe Microscopy Measurements On 2d Materials And Iridates, Armin Ansary

Theses and Dissertations--Physics and Astronomy

In the past two decades, there has been a quest to understand and utilize novel materials such as iridates and two-dimensional (2D) materials. These classes of materials show a lot of interesting properties both in theoretical predictions as well as experimental results. Physical properties of some of these materials have been investigated using scanning probe measurements, along with other techniques.

One-dimensional (1D) catalytic etching was investigated in few-layer hexagonal boron nitride (hBN) films. Etching of hBN was shown to share several similarities with that of graphitic films. As in graphitic films, etch tracks in hBN commenced at film edges and …

Biomaterials For Bone Regeneration, Youqu Shen

Doctoral Dissertations

"The purpose of this Ph.D. research is to investigate and improve two classes of hydroxyapatite (HA)-based biomaterials for bone repair: calcium phosphate microspheres and bioactive silicate glass scaffolds. These biomaterials were prepared with modified compositions and microstructures and then were evaluated for bone regeneration.

The open HA microspheres with dense convex surfaces and rough and porous concave surfaces were obtained by sectioning closed hollow HA microspheres. Bone regeneration with the open HA microspheres was greater than with the closed HA microsphere at 12 weeks. Hollow biphasic calcium phosphate (BCP) microspheres have been prepared with different fractions of HA and β-TCP …

การเตรียมวัสดุดูดซับคาร์บอนไดออกไซด์จากมีโซพอรัสซิลิกาและเส้นใยเซลลูโลสที่มีหมู่ฟังก์ชันเอมีน, จัตุพร เลิศบุญเรือนกุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาผลของตัวแปรต่าง ๆ ต่อความสามารถในการดูดซับแก๊สคาร์บอนไดออกไซด์ของวัสดุดูดซับที่เตรียมได้จากมีโซพอรัสซิลิกาและเส้นใยเซลลูโลสที่มีหมู่ฟังก์ชันเอมีนภายใต้ความดันบรรยากาศ โดยตัวแปรที่ทำการศึกษาประกอบด้วย ชนิดของวัสดุดูดซับ อัตราส่วนโดยมวลระหว่างมีโซพอรัสซิลิกาและเส้นใยเซลลูโลส ชนิดของสารลดแรงตึงผิวที่ใช้ในการสังเคราะห์มีโซพอรัสซิลิกา ชนิดของเส้นใยเซลลูโลส ความเข้มข้นของแก๊สคาร์บอนไดออกไซด์ในกระแสแก๊ส ปริมาณเตตระเอทิลีนเพนตะมีนที่ตรึงบนวัสดุดูดซับ ความเข้มข้นของไอน้ำในแก๊สผสมขาเข้า อุณหภูมิการดูดซับ และความเสถียรของวัสดุดูดซับ จากผลการทดลองพบว่า วัสดุดูดซับมีโซพอรัสซิลิกาที่สังเคราะห์โดยใช้สารลดแรงตึงผิวซิติลไตรเมทิลแอมโมเนียมโบรไมด์และเส้นใยเซลลูโลสจากเยื่อคราฟท์ยูคาลิปตัสฟอกในอัตราส่วน 0.75:0.25 ที่ตรึงด้วยเตตระเอทิลีนเพนตะมีนร้อยละ 40 โดยน้ำหนัก (40%TEPA/(0.75:0.25)m-SiO2(CTAB)-sP) มีความสามารถในการดูดซับแก๊สคาร์บอนไดออกไซด์สูงสุด เท่ากับ 5.532 มิลลิโมลต่อกรัมตัวดูดซับ ภายใต้ภาวะที่ใช้ในการทดสอบการดูดซับที่อุณหภูมิการดูดซับ 70 องศาเซลเซียส ความเข้มข้นของแก๊สคาร์บอนไดออกไซด์ในกระแสแก๊สร้อยละ 30 โดยปริมาตร และความเข้มข้นของไอน้ำในแก๊สผสมขาเข้าร้อยละ 2 โดยปริมาตร นอกจากนี้วัสดุดูดซับที่เตรียมได้ยังสามารถนำกลับมาใช้ใหม่ได้สูงถึง 8 รอบวัฏจักรการดูดซับและคายซับ โดยความสามารถในการดูดซับแก๊สคาร์บอนไดออกไซด์ของวัสดุดูดซับมีค่าลดลงเพียงร้อยละ 6.42 จากวัฏจักรการดูดซับรอบแรก