Materials Science and Engineering Commons^™

Assessment Of Wafer Scale Mos2 Atomic Layers Grown By Metal–Organic Chemical Vapor Deposition Using Organo-Metal, Organo-Sulfide, And H2S Precursors, Michael Curtis, Olivia Moryan, Nicholas Mckibben, Josh Eixenberger, Chen Chen, Karthik Chinnathambi, Sergej Pasko, Salim El Kazzi, Joan M. Redwing, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

Transition Metal Dichalcogenides (TMDs) are a unique class of materials that exhibit attractive electrical and optical properties which have generated significant interest for applications in microelectronics, optoelectronics, energy storage, and sensing. Considering the potential of these materials to impact such applications, it is crucial to develop a reliable and scalable synthesis process that is compatible with modern industrial manufacturing methods. Metal–organic chemical vapor deposition (MOCVD) offers an ideal solution to produce TMDs, due to its compatibility with large-scale production, precise layer control, and high material purity. Optimization of MOCVD protocols is necessary for effective TMD synthesis and integration into mainstream …

Developing And Testing Low-Cost Air Cleaners For Safer Spaces During Wildfires, Brett W. Stinson, Elliott T. Gall

Mechanical and Materials Engineering Faculty Publications and Presentations

Air cleaning reduces indoor exposure to fine particulate matter (PM2.5) during wildfire smoke events. However, resource and cost constraints may limit access to air cleaning during such an event, as both commercial devices and the higher-rated MERV filters that do-it-yourself (DIY) assemblies typically rely upon tend to be expensive and in short supply. With these constraints in mind, we developed and evaluated several configurations of a novel, DIY air cleaner that uses common household fabrics as filtration media. Clean air delivery rates (CADRs) of the devices were experimentally evaluated in two ways: first, with independent measurements of flowrates and single …

The Role Of Furan Moieties On The Thermal Decomposition And Char Formation Of Intrinsically Fire-Resistant Epoxy Thermosets For Composites, Amy E. Honnig Bassett

Theses and Dissertations

Fire-retardant chemicals added to epoxy thermosets used as coatings, adhesives, and fiber-reinforced polymer composites (FRPCs) negatively impact performance and the environment. This dissertation takes a novel approach to mitigate the flammability of these systems by designing intrinsically fire-resistant epoxies via the incorporation of furan moieties. Glycidyl amines based on furfuryl amine and judiciously selected derivatives of furfuryl amine were synthesized to produce furan-based di-epoxies (FDEs) that were cured by anionic polymerization and with amine curing agents. The furan ring was found to impart additional reactivity for cross-linking and to induce char-forming reactions at higher temperatures. More importantly, the placement of …

Annual Progress In Global Carbon Capture, Utilization, And Storage In 2023, Siyuan Fang, Yun Hang Hu

Michigan Tech Publications

Since the industrial revolution, global anthropogenic CO2 emissions have surged dramatically to unsustainable levels, resulting in severe issues, such as global warming, extreme weather events, and species extinction. In response to this critical situation, extensive efforts have been undertaken across academia, industry, and policymaking sectors to deploy carbon capture, utilization, and storage (CCUS) technologies. Here, we present the annual summary of global CCUS for the year 2023. We begin by discussing the trends of anthropogenic CO2 emissions and atmospheric CO2 concentrations, and then offer an up-to-date summary of progress in academia, industry, and policy, respectively. In academia, we analyze the …

Experimental Investigation On Mechanical Properties Of Pla Reinforced By Bamboo Fiber/Montmorillonite Clay Hybrid Composites And Analysis Of Machining Characteristics, Nirmal Kumar K

Theses and Dissertations

The study presents a comprehensive investigation into the development, characterization, and machining analysis of novel bio-based polymer hybrid composites comprising Polylactic acid (PLA), bamboo powders (BP), and montmorillonite clay particles (MMT). Initially, the hybrid composites were fabricated using a solvent-free stir casting process, optimizing the weight percentages of BP and MMT to enhance mechanical and thermal properties.

Mechanical tests, including tensile, flexural, and impact tests, along with thermal analysis using thermogravimetric analysis and differential scanning calorimetry, were conducted to evaluate the performance of the composites. In the subsequent phases, advanced machining techniques were employed to analyze the machining characteristics of …

Optical Responses Of Hybrid Electromagnetic Nanostructures, Dominic Bosomtwi

Optical Science and Engineering ETDs

Fano resonances result from the interference between a broad background and a narrow state, producing asymmetric scattering profiles. Under specific conditions, destructive interference collapses the Fano resonance width, leading to bound states in the continuum (BICs) that localize light within a nanostructure while maintaining an infinitely high-quality factor (Q-factor).

This dissertation explores the design of nanostructures with multilayer hybrid plasmonic-dielectric metasurfaces using full-wave numerical simulations, facilitating multiple Fano resonances and BICs. By adjusting nanoantenna dimensions, multiple modes are excited at plasmonic-dielectric interfaces, leading to strong interactions and hybridization of energy levels, manifested as Rabi splitting.

These findings enable advancements in …

Article Comprising Bonded Substrate Comprising Nanocrystals And Method Of Making And Using Same, Michael D. Sherburne

AFIT Patents

The present invention relates to devices for measuring property changes via in-situ micro-viscometry and methods of using same. The aforementioned device is inexpensive and can be used to quickly and accurately measure numerous physical and chemical property changes, including but not limited to the rate of chemical cure, change in tack, and rate of mass loss, for example, rate of moisture, solvent and/or plasticizer change.

Synthesis, Crystal Structure, Hirshfeld Surface And Void Analysis Of 2-Amino-1h-Benzimidazolium 2-Hydroxybenzoate, Salmon M. Mukhammadiev, Daminbek A. Ziyatov, Zuhra Ch. Kadirova, Jamshid M. Ashurov, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is determination of crystal structure and Hirschfeld surface void analysis for many intermolecular interactions in the crystal structure of 1,3-dihydro-2H-benzimidazole-2-iminium-2-hydroxy-5-sulfobenzoate.. For the first time, a new organic salt containing organic benzimidazolium cations and sulfosalicylic anions was synthesized and structurally characterized. Hirshfeld surface analysis confirm that in the crystal shape most remarkable contacts are H∙∙∙O (38%) and H∙∙∙H (29.7%) There are some π–π stacking interactions in the crystal shape.

Synthesis Of Cationite Based On Indene, A Secondary Product Of Hydrocarbons Pyrolysis, Saidmansur Sh. Saidobbozov, Suvonkul E. Nurmanov, Dilorom H. Mirkhamitova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study is extraction of the indene from pyrolysis oil obtained from the pyrolysis of hydrocarbons at the Ustyurt gas processing plant. Indene is isolated by rectification from the composition of pyrolysis oil formed as a by-product of the process of hydrocarbons pyrolysis at the Ustyurt gas processing plant. Polymethyleneindenesulfocationite was synthesized on the basis of isolated indene, and its structure and physicochemical properties were determined. Chromatomass spectrum of pyrolysis oil was obtained and analyzed. The indene fraction and the synthesized polymethyleneindenesulfocationite were analyzed using IR spectroscopy and SEM (scanning electron microscopy). Thermal analysis of cationite was …

Preparation Of Keratin-Containing Protein Compounds From Chickens Feathers Using Hydrochloric Acid, Dilnozakhon I. Tursunova, Oytura S. Maksumova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is the preparation of keratin-containing protein compounds from poultry processing waste by hydrolysis with hydrochloric acid, including treatment of the protein with 5% H₂O₂. The process of cleaning feather raw materials using water, liquid soap, NaClO₃, C₂H₅OH, and H₂O_2, and the reaction of its hydrolysis with an aqueous solution of HCl have been studied. The influence of temperature and reaction duration on the hydrolysis process was studied, and its optimal mode was established. It has been shown that the process of …

Synthesis And Research Of Adsorbents And Catalysts Obtained By Processing Of Industrial Wastes, Shuhratqodir T. Gulyamov, Sherzod A. Омоnоv, Shaxnoz B. Jalalova, Dilnoza P. Turdieva, Rufatjon F. Boymonov

CHEMISTRY AND CHEMICAL ENGINEERING

The purposes of the study are the synthesis of granular aluminum oxide and magnesium-aluminum spinel using various residues formed during thermochemical regeneration of adsorbents deactivated by chloride compounds, the physicochemical characteristics and catalytic properties of catalysts. The main parameters for processing aluminum-containing waste using sulfuric acid technology to produce pseudoboehmite have been identified. Adsorbents, as well as carriers and catalysts obtained using pseudoboehmite and alkaline waste have been studied using diffractometry, thermography and elemental analysis. The conditions for the synthesis of mechanically strong granules containing magnesium and calcium aluminates have been determined. Based on pseudoboehmite, aluminum oxide adsorbents with texture, …

Influence Of Solid-Phase And Melt Synthesis Methods On The Structure And Electrochemical Properties Of Na3fe2(Po4)3 Polycrystals, Adolf S. Nogai, Artur A. Nogai, Daniyar E. Uskenbaev, Eleonora A. Nogai, Alexander A. Bush

CHEMISTRY AND CHEMICAL ENGINEERING

The article studies the influence of solid-phase and melt synthesis methods on the structure and electrochemical properties of the Na₃Fe₂(PO₄)₃ polycrystals. If the solid-phase synthesis of the Na₃Fe₂(PO₄)₃ polycrystals (type 1 of samples) is carried out using ceramic technology, initially glassy precursors are first obtained by melting the starting materials under the influence of optical radiation energy at the melt synthesis method, and the Na₃Fe₂(PO₄)₃ polycrystals are obtained after firing (type 2 of samples). With this method, the synthesis …

Study Of The Process Of Foam Formation During Nitric Acid Decomposition Of Dolomite Raw Materials, Oybek A. Mikhliev, Kholtura Ch. Mirzakulov, Ruslan Ch. Yorbobaev, Shahodat M. Olmurova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the work is acceleration of the process of nitrate decomposition of local dolomite raw materials and study its processing into MgOH, MgO, liquid and granular magnesium fertilizers. We studied the effect of "PAA-gel" and "Struktol SB 2195" on the foam expansion ratio and filtration rate, as well as the influence of acid concentration and temperature on the rheological properties of the acidic pulp and the liquid and solid phases formed during its separation. The qualitative and quantitative compositions were determined. As a result, an increase in the filtration rate and a decrease in the rate of foaming …

Microwave Synthesis Of Yttrium Oxide Nanostructure Powders, Doped With Ytterbium And Erbium Ions, Eygeniy N. Poddenezhny, Andrei A. Boiko, Olga V. Davydova, Ekaterina E. Trusova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was to develop microwave synthesis of luminescent yttrium oxide powders doped with ytterbium and erbium ions (Y₂O₃:Yb³⁺_, Er³⁺) in the process of homogeneous precipitation from a reaction mixture of yttrium, ytterbium and erbium chlorides. The characteristics of the obtained powders were studied by X-ray diffraction, scanning and passing electron microscopy, differential thermal analysis, IR spectroscopy and photoluminescence under IR excitation. From luminescence spectra of Y₂O₃:Yb³⁺, Er³⁺ samples obtained by excitation with an IR laser at a wavelength of 975 nm, …

Optical Glass With Increased Refractive Index Based Bao – B2o3 – Sio2 System, Yury G. Pavliukevich, Ludmila F. Pаpko, Ekaterina E. Trusova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research is to develop lead-free optical glass with increased refractive index based on BaO – B₂O₃ – SiO₂ system. A study of technological and physical-chemical properties of glass was conducted. It has been shown that the glass of this system tends to the phase separation of segregation type. The area of glass composition with refractive index of 1.6195 – 1.6650 has been established. The peculiarities of influence of the modifiers – Al₂O₃ and oxides of the RO group – on the technological and optical properties of the glass of …

Tribocorrosion And Metal Release From Austenitic Stainless Steels 304 And 201 In Simulated Cassava Food Contact, Robert Addai, Temitope E. Olowoyo, Thalia E. Standish, Jeffrey Daniel Henderson, Ubong Eduok, Yolanda Hedberg

Chemistry Publications

Cassava is the third most significant calorie source in the tropics. Its processing has changed from traditional methods to stainless steel processing machines. This study investigated the influence of cassava on metal release from two common stainless steels, ASTM 304 and 201, with and without friction, and on tribocorrosion (multianalytically) of 304. Cassava was relatively corrosive and hindered repassivation of the surface oxide of stainless steel, but it also acted as a lubricant against mechanical friction. The combined action of friction and cassava caused a significant increase in iron, chromium, nickel, and manganese release from the stainless steels (30–35- fold …

Pulsing-Induced Healing Of A Surface Crack Of A Nickel-Based Alloy, Liwei Wang, Mingming Quan, Zhen Tan, Ming Liu, Dianlong Wang, Xiao Yang, Ying Liu, Yaning Mao, Zhimin Liang, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

In this work, we demonstrate the feasibility of applying electric pulses to heal surface cracks on nickel-based alloy GH4169 under compressive load. There exists an incubation time for the onset of the healing of a crack, which is associated with local temperature at the crack tip. The crack size decreases with increasing the pulsing time at a constant healing rate prior to complete healing of the crack. Increasing compressive load accelerates the healing process. The electric pulsing leads to the formation of an influential zone surrounding the crack with the finest grain sizes in the healed crack and the coarsest …

Microstructural Evolution In A Precipitate-Hardened (Fe0.3ni0.3mn0.3cr0.1)94ti2al4 Multi-Principal Element Alloy During High-Pressure Torsion, Matthew Luebbe, Jiaqi Duan, Peipei Cao, Zhaoping Lu, Rinat K. Islamgaliev, Ruslan Z. Valiev, Yuzi Liu, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Multi-principal element alloys demonstrate high strength, thermal stability, and irradiation resistance, making them excellent candidate materials for applications in nuclear reactors and other harsh environments. Some studies have examined the use of high-pressure torsion to strengthen MPEAs through grain size reduction and strain hardening. However, no studies have investigated the effect of HPT on secondary phases (precipitates) within an MPEA. Two alloys, (Fe_0.3Ni_0.3Mn_0.3Cr_0.1)₉₄Ti₂Al₄ containing Ni(Ti, Al) B2 phase, and CrFe σ phase, and single-phase Fe_0.3Ni_0.3Mn_0.3Cr_0.1, were fabricated by casting …

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures Phase 2, Andrea Calabrese, Pitiporn Asvapathanagul, Nisarg N. Patel, Nanubala Dhruvan, Austin Adams, Michael Hernandez, Douglas S. Lopez-Cruz

Mineta Transportation Institute

Concrete is a critical component of so much of the modern construction industry. This material, well known for its versatility, robustness, longevity, and strength, is well-suited for a wide range of structural applications. Nonetheless, the widespread occurrence of cracks in concrete structures, primarily attributed to its limited tensile strength, shrinkage, and overstain, imposes a considerable economic and environmental challenge when it comes to retrofitting these fissures. This study tackles this problem by harnessing bacteria tolerant to high alkaline conditions to enable Microbially Induced Calcium Carbonate Precipitation (MICP) for the self-repair of concrete. This is achieved through an external application method, …

Poly(Thioether) Thermosets With Gated Photodegradation, Surabhi Jha

Dissertations

Photodegradable polymer networks are attractive due to the precise spatiotemporal control and large-area applicability of light. Chemical linkages that enable these polymer networks to be photo-responsive, also hinder their applicability in ambient light. Photostable and photodegradable networks have recently been reported to overcome this challenge by combining other stimuli with light for degradation. We report the design of a network that responds to a simultaneous, dual stimulus for photodegradation. We design poly(thioether acetal) networks with benzylidene acetal moieties that are known to undergo β-scission in the presence of free thiols. By blocking these free thiols with a thermally labile protecting …

Electrical And Morphological Investigation Of A Fe(Ii) Based Spin Crossover Complex And Its Composite, Rifat Mahbub

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Spin crossover (SCO) complexes have unique properties of switching their spin state upon perturbations like temperature, pressure, light, etc. Along with the spin state, different properties vary like structural, electrical, magnetic, optical properties. This enables these materials to be potentially used in various applications like molecular electronics, memory devices, switching devices, sensors and many more. To incorporate spin crossover materials into devices with efficient performance, the electrical behavior needs to be understood. This dissertation aims to investigate the effect of crystal structure on the electrical properties of iron(II) triazole spin crossover complex and how it can be modified for better …

Understanding And Tuning Magnetism In Layered Ising-Type Antiferromagnet Fepse3 For Potential 2d Magnet, Rabindra Basnet, Taksh Patel, Jian Wang, Dinesh Upreti, Santosh Karki Chhetri, Gokul Acharya, Md Rafique Un Nabi, Joshua Sakon, Jin Hu

Chemistry & Biochemistry Faculty Publications and Presentations

Recent developments in 2D magnetic materials have motivated the search for new van der Waals magnetic materials, especially Ising-type magnets with strong magnetic anisotropy. Fe-based MPX₃ (M = transition metal, X = chalcogen) compounds such as FePS₃ and FePSe₃ both exhibit an Ising-type magnetic order, but FePSe₃ receives much less attention compared to FePS₃. This work focuses on establishing the strategy to engineer magnetic anisotropy and exchange interactions in this less-explored compound. Through chalcogen and metal substitutions, the magnetic anisotropy is found to be immune against S substitution for Se whereas …

Growth And Simulation Of Dielectric-Metal Nanoheterostructured Thin Films By Ballistic Deposition, Shawn Wimer

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This thesis is divided into two related topics: the structural and chemical characterization of dielectric-metal nanoheterostructured thin films grown by glancing angle deposition (GLAD) and the results of the simulated growth of films and structures by GLAD with discrete-space and continuous-space Monte Carlo ballistic simulation.

Individual structures comprising films grown by GLAD were investigated by S/TEM and SEM imaging, electron diffraction, and chemical characterization and mapping by EDX. Different intermolecular interactions within and between different materials, including Si, Ag, Au, and ZrO₂, are linked to differences in the shapes of individual materials in heterostructures, the shape of heterostructures …

Laser 3d Printing Of Diamond-Based Composite Materials For Thermal Management Applications, Nada Kraiem

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

With the trend towards miniaturization of electrical equipment and the constant increase in power density in semiconductor devices, efficient heat management has become a major concern for researchers. Indeed, this technological evolution imposes increasingly strict constraints in terms of thermal dissipation, necessitating innovative solutions to ensure better durability and reliability of components. In this context, the use of composite materials offering high thermal conductivity (TC) and low coefficient of thermal expansion (CTE) compared to pure metals has become essential to address overheating issues in electronic components.

The utilization of advanced materials such as diamond (D), with exceptional TC and hardness …

Advancements In Microscale Tensile Testing: A Novel Device For The High Throughput Analysis Of Two-Photon Polymerized Microfibers In Liquid, Grayson D. Minnick

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Two-photon polymerization (TPP) enables the 3D fabrication of micro- and nanostructures from biocompatible materials with high resolutions, reaching into the realm of hundreds of nanometers. Such capabilities are crucial for advancing applications in fields like mechanobiology. As microscale technologies evolve, the precise characterization of material properties becomes increasingly essential. This is especially true for TPP-printed microstructures serving as scaffolds for 3D cell culture and intended for studying the mechanics of tissues. Despite the importance, traditional micro-scale tensile testing methods typically lack scalability and fail to replicate relevant environmental conditions. This dissertation introduces a new device that is specifically designed to …

Dual Light Emission Of Cssni3-Based Powders Synthesized Via A Mechanochemical Process, Xuan Huang, Xiaobing Tang, Xiyu Wen, Yuebin Charles Lu, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

Lead toxicity has hindered the wide applications of lead halide perovskites in optoelec- tronics and bioimaging. A significant amount of effort has been made to synthesize lead-free halide perovskites as alternatives to lead halide perovskites. In this work, we demonstrate the feasibility of synthesizing CsSnI3-based powders mechanochemically with dual light emissions under ambi- ent conditions from CsI and SnI2 powders. The formed CsSnI3-based powders are divided into CsSnI3-dominated powders and CsSnI3-contained powders. Under the excitation of ultraviolet light of 365 nm in wavelength, the CsSnI3-dominated powders emit green light with a wavelength centered at 540 nm, and the CsSnI3-contained powders …

Carbon-Based Nanocomposite Membranes For Membrane Distillation: Progress, Problems And Future Prospects, Chhabilal Regmi, Yuwaraj K. Kshetri, S. Ranil Wickramasinghe

Chemical Engineering Faculty Publications and Presentations

The development of an ideal membrane for membrane distillation (MD) is of the utmost importance. Enhancing the efficiency of MD by adding nanoparticles to or onto a membrane’s surface has drawn considerable attention from the scientific community. It is crucial to thoroughly examine state-of-the-art nanomaterials-enabled MD membranes with desirable properties, as they greatly enhance the efficiency and reliability of the MD process. This, in turn, opens up opportunities for achieving a sustainable water–energy–environment nexus. By introducing carbon-based nanomaterials into the membrane’s structure, the membrane gains excellent separation abilities, resistance to various feed waters, and a longer lifespan. Additionally, the use …

Enhancement Of Polytetrafluoroethylene-Polyvinyl Alcohol Nanofibers Triboelectric Effect With Carboxylic Functionalized Multiwalled Carbon Nanotubes Coating, Fernando Viesca

Theses and Dissertations

In this study, we fabricated a TENG using Forcespinning® (FS) Polytetrafluoroethylene microfibers (FS-PTFE-MFs) and Electrospun (ES) Polyvinyl alcohol nanofibers (ES-PVA-NFs). The FS-PTFE-MFs were physically linked with functionalized carboxylic multiwall carbon nanotubes (MWCNTs-COOH) employing water dispersions. MWCNTs-COOH were dispersed using three different surfactants: Sodium Dodecyl Sulfate (SDS), Sodium dodecylbenzenesulfonate (SDBS), and Triton X-100 (TX-100). Coated FS-PTFE-MFs were then characterized using a field emission scanning electron microscope (FESEM) with an energy dispersive X-ray spectroscopy (EDS) attachment and Fourier-transform infrared spectroscopy (FTIR). While no significant difference in performance was observed with different surfactants, electrical results of the TENG recorded a notable enhancement of …

Performance Evaluation Of Asphalt Binder Modified With Recycled Plastics, Abeeb G. Oyelere

Graduate Theses and Dissertations (2019 - present)

The surge in the production of plastic waste has become a pressing global environmental issue. To address this, repurposing plastic waste to modify asphalt binders in asphalt pavement is being explored This study investigates the potential of recycled high-density polyethylene (rHDPE) and recycled polypropylene (rPP) as asphalt binder modifies to improve pavement performance and sustainability while mitigating plastic waste's adverse environmental impacts. Laboratory investigations were conducted to assess the rheological performances as well as the compatibility of rHDPE and rPP-modified asphalt. Additionally, the impact of aging and mixing temperature on rheological performance was investigated. Experimental results indicated that adding these …

Mesostructure Reconstruction Of Prepreg Platelet Molded Composite With Artificial Intelligence, Richard Larson

Mechanical & Aerospace Engineering Theses & Dissertations

Prepreg platelet molded composites (PPMC) are long, discontinuous fiber reinforced polymer materials. PPMC are an important subcategory of composite materials as they are processible into geometrically complex structures and can be produced via high-throughput manufacturing processes, however they have higher stiffness and strength as compared to traditional discontinuous fiber reinforced polymers. However, there is inherent randomness in the structure of PPMCs and as such, PPMC parts frequently require per part testing that is cost prohibitive.

Herein, a method using artificial intelligence is proposed as a more cost-effective method of inspecting PPMC parts. Different artificial intelligence (AI) architectures are explored to …