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Ac Conductivity Studies Of Polyethylene-Oxide-Garnet Type Li7la3zr2o12 Hybrid Composite Solid Polymer Electrolyte For Li-Ion Battery, Parisa Bashiri

Wayne State University Dissertations

Solid electrolytes including ceramics and polymers are considered to be the ultimate substitute for organic liquid electrolytes currently used in commercialized lithium ion batteries to address the safety concerns due to Li dendrite growth and internal short circuiting. However, low ionic conductivity due to high grain boundary resistance in ceramics and semi-crystalline nature of polymers has held back the solid electrolytes from being used in Li-ion batteries. Polyethylene oxide (PEO), complexed with a Li-salt, is a well-studied polymer electrolyte showing ionic conductivity properties at room temperature. However, the coexistence of amorphous and crystalline regions at room temperature (< Tm, the melting temperature) has

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Investigation Of Physiochemical Properties And Biocompatibility Of Amourphos Calcium Polyphosphate Hydrogel Doped With Antibiotics And Injectable Polymeric Dicalcium Phosphate Dihydrate Bone Cement, Yasaman Chehreghanianzabi

Wayne State University Dissertations

Amorphous calcium polyphosphate (ACPP) is an inorganic polymer ceramic. Here we use a simple method of preparing ACPP hydrogel in the presence of excess volume of water. Essentially, water availability to polyphosphate chains accelerates water molecule ingress and microstructural transformation of ACPP hydrogels. Antibiotic delivery capacity of ACPP hydrogel increases by the specific mixing and molding method, where the VCM has higher antibiotic encapsulation efficiency with the small burst release for the compressed discs. In part of this study, we investigate impact of ACPP hydrogel replacement by monomeric calcium phosphate on the quality of final product (dicalcium phosphate dihydrates (DCPD) …

Study Of Grain Growth In Single-Phase Polycrystals, Pawan Vedanti

Wayne State University Dissertations

Materials with random microstructure are characterized by additional thermodynamic parameters, entropy and temperature of microstructure. It has been argued that there is one more law of thermodynamics: entropy of microstructure decays in isolated systems. This assertion has been checked experimentally for the process of grain growth which showed that entropy of grain structure decays indeed as expected. The equation of state for microstructure entropy has also been studied. In general, entropy of grain microstructure is expected to be a function of grain structure energy and the average grain size. Our experiments suggest that in fact, the equation of state degenerates …

Advanced Electrodes And Electrolytes For Long-Lived And High-Performance Lithium-Sulfur Batteries, Deepesh Gopalakrishnan

Wayne State University Dissertations

ABSTRACT

ADVANCED ELECTRODES AND ELECTROLYTES FOR LONG-LIVED AND HIGH-PERFORMANCE LITHIUM-SULFUR BATTERIES

by

DEEPESH GOPALAKRISHNAN

August 2020

Advisor: Dr. Leela Mohana Reddy Arava

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Lithium – Sulfur (Li-S) batteries have received much attention and considered as a promising candidate for next generation energy storage devices because of their high theoretical energy density (≈2600 Wh kg‒1) and environmental friendliness. However, the uncontrollable growth of lithium dendrites in the lithium metal anode and the fatal effect of polysulfide shuttle hinder their practical applications. The formation of dendrites during repeated Li plating/stripping processes results in: reduced Li availability …

Engineering Of Gold Nanoparticles For Drug Delivery, Fangchao Liu

Wayne State University Dissertations

Due to their ease of synthesis, versatile surface chemistry, ease of imaging, and biocompatibility, gold nanoparticles (AuNPs) are employed as drug delivery devices in the treatment of respiratory problems associated with spinal cord injury (SCI). We have developed a method for the synthesis of a tripartite nanoconjugate comprised of an AuNP drug carrier chemically conjugated to a transporter protein (wheat germ agglutinin coupled to horseradish peroxidase or WGA-HRP) and to potent SCI drugs. The therapeutic efficacy and biodistribution were studied in a validated animal model. Our results show that a single administration of the nanoconjugate improved diaphragmatic activity at a …

Rare-Earth-Activated Group Vi D0 Metal Oxides As Thermosensitive Phosphors, Samarage Sameera Perera

Wayne State University Dissertations

ABSTRACT

RARE-EARTH-ACTIVATED GROUP VI d0 METAL OXIDES AS

THERMOSENSITIVE PHOSPHORS

by

SAMARAGE SAMEERA PRASAD PERERA

AUGUST 2019

Advisor: Dr. Federico A. Rabuffetti

Major: Chemistry

Degree: Doctor of Philosophy

Thermosensitive phosphors are solid-state materials that demonstrate distinct dependence of luminescence emission on temperature. These materials enable optical temperature sensing in environments where conventional thermometry is not possible (e.g., gas turbines, combustion engines, surface temperature distributions). However, the design of thermosensitive phosphors that show adequate sensitivity and low thermal quenching in the intermediate temperature range (i.e., 500–1000 K) remains challenging. This challenge can be addressed by understanding how to rationally manipulate the …

Direct Laser Metal Deposition Of Nickel Based Superalloys, Abhishek Ramakrishnan-Sudha

Wayne State University Dissertations

Nickel-based superalloys are substantially used in the manufacturing of boilers for ultra-supercritical power plants and gas turbine hot-section as this grade of alloys provide higher yield strength with the rise in operating temperature and pressure owing to the presence of γʹ second phase precipitates. Conventionally, casting techniques such as centrifugal casting, investment casting, vacuum molding and several other casting based methods are used to fabricate the hot-section components. Nevertheless, a need for designing advanced materials with complex designs such as geometry, microstructure control, compositional changes, microstructure and property varying with the location as in functionally graded materials is not viable …

Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro

Wayne State University Dissertations

The work reported in this thesis focused on providing a fundamental understanding, at the molecular level, required to guide the effective design of electrocatalysts towards a superior reaction kinetics on the electrode of solid oxide electrolysis cells SOECs devices (SOECs) during the CO2 electrolysis. High temperature SOECs are electrochemical energy conversion technologies, that have emerged as promising alternatives to mitigate environmental issues associated with combustion-based technologies, such as the rising atmospheric CO2 levels. The conversion of excess CO2 into high-energy molecules, such as CO can be efficiently achieved through the use of SOEC – which facilitates the electrochemical reduction of …

Immune Modulation By Amphiphilic Oligonucleotides, Chunsong Yu

Wayne State University Dissertations

Immunotherapy is emerging as one of the most promising therapeutic strategies for cancer treatment in clinical practice. Immunotherapy leverages the host’s immune system to attack and kill tumor cells. Rationally-designed cancer vaccines are emerging as one of the powerful immunotherapies primarily because of the promise of inducing tumor antigen-specific immune responses. To improve immunogenicity of cancer vaccines, vaccine antigens are administered with vaccine adjuvants which can robustly activate innate immune system and subsequently lead to adaptive immune response. However, the major challenge of achieving significant therapeutic efficacy is lack of efficient targeted-delivery of vaccine components. By taking advantage of endogenous …

Novel Cathode Framework, Effective Electrolyte Modification, And Electrode Structural Modification Of High Performance Lithium Sulfur Batteries, Wenduo Zeng

Wayne State University Dissertations

Firstly, TiN nanotube arrays have been investigated as an effective skeleton in the cathode of lithium-sulfur batteries. A series of TiN nanotubes with various diameter and length have been synthesized and tested. Moreover, graphene nanoplatelets have been utilized as a structural anchor to support the TiN nanotubes, and the synergetic effect of composite material and its enhancement on Li-S battery electrochemical performance and cycling stability have been studied. Secondly, the improvement of electrode structural design has been evaluated for their effectiveness by using an in-situ characterization method with other electrochemical characterization. Lastly, the facile method of using transition metal cations …

Engineering Hyaluronic Acid Carbon Nanotube Nanofibers: A Peripheral Nerve Interface To Electrically Stimulate Regeneration, Elisabeth M. Steel

Wayne State University Dissertations

Peripheral nerve injuries annually affect hundreds of thousands of people globally. Current treatments like the gold standard autograft and commercially available nerve guide conduits (NGC) are insufficient to repair long gap peripheral nerve injuries. NGCs can aid recovery but lack key microenvironment cues that promote nerve regeneration. We hypothesized that providing topographical, mechanical, and electrical guidance cues through a nanofibrous composite biopolymer would result in improved neuron growth metrics using an in vitro model. We embedded hydrophilic carbon nanotubes (CNT) within hyaluronic acid (HA) nanofibers by electrospinning. The aims of this study were (1) to define the topographical, nanomechanical, and …

Synthesis Of Volatile And Thermally Stable Aluminum Hydride Complexes And Their Use In Atomic Layer Deposition Of Metal Thin Films, Kyle Blakeney

Wayne State University Dissertations

The research discussed in this dissertation spans both synthetic inorganic and nanomaterials chemistry. Aluminum hydride complexes have been synthesized and characterized which are highly volatile and thermally stable and their potential as reducing agents for ALD of electropositive metal and metal-containing films was evaluated. A major discovery has been the deposition of aluminum metal films by thermal ALD using an aluminum dihydride complex supported by a simple amido-amine ligand (Chapters 2). Aluminum is the most electropositive element deposited by purely thermal ALD to date and represents a significant breakthrough for this field. This process may have important industrial applications and …

Development Of Nanostructured Austempered Ductile Cast Iron, Saranya Panneerselvam

Wayne State University Dissertations

Austempered Ductile Cast Iron is emerging as an important engineering materials in recent years because of its excellent combination of mechanical properties such as high strength with good ductility, good fatigue strength and fracture toughness together with excellent wear resistance. These combinations of properties are achieved by the microstructure consisting of acicular ferrite and high carbon austenite. Refining of the ausferritic microstructure will further enhance the mechanical properties of ADI and the presence of proeutectoid ferrite in the microstructure will considerably improve the ductility of the material.

Thus, the focus of this investigation was to develop nanostructured austempered ductile cast …

Zwitterionic Polymer Materials For Nanoparticle Stabilization, Cell Encapsulation And Anti-Fouling Coating, Wei Wang

Wayne State University Dissertations

Based on the superior anti-fouling property, the zwitterionic materials had great potential in applications such as medical implants, medical device coating, and marine coating industry. This thesis will focus on the applications of zwitterionic materials in stabilizing carbon nanoparticles, as implantable devices and durable coating on medical devices for long-term anti-microbial purposes. Chapter 2 of the thesis will discuss a simple method to synthesis carbon nanoparticles stabilized by zwitterionic polymers. Chapter 3 of the thesis reports the use of zwitterionic hydrogel to encapsulate islet of Langerhans to treat Type 1 diabetes. In Chapter 4 and 5, several methods were developed …

Bioreducible Layer-By-Layer Films For Gene Delivery, Lingxiao Xie

Wayne State University Dissertations

Layer-by-Layer (LbL) gene delivery system is fabricated by polycation and plasmid DNA alternative deposition based on electrostatic force between each other. This dissertation explored the relationship between LbL film assembly and disassembly. Demonstrated that the film disassemble process is closely related to film interior structure. LbL interlayer diffusion, which is caused by the polyelectrolytes own properties, such as polymer chain length, molecular weight, and charge density, can influence film growth mode. The interlayer diffusion is the main reason to lead fast and bulk DNA releasing of bioreducible LbL film. Preventing interlayer diffusion by inserting small diffusion coefficient polymer, such as …

Synthesis Of Discrete Transition Metal (Ni, Fe, Co, Mn) Phosphide Nanoparticles: Compositional Effect On Catalytic And Magnetic Properties, Da Li

Wayne State University Dissertations

This dissertation research is focused on the synthesis, characterization of binary and ternary transition metal (Ni, Co, Fe, Mn) phosphide nanomaterials and their catalytic and magnetic properties.

A phase-control strategy enabling the arrested-precipitation synthesis of nanoparticles of Ni5P4 and NiP2 is presented. The composition and purity of the product can be tuned by changing key synthetic levers, including the metal precursor, the oleylamine (OAm) and Trioctylphosphine (TOP) concentrations, temperature, time and the presence or absence of a moderate temperature soak step to facilitate formation of Ni and/or Ni-P amorphous nanoparticle intermediates.

New CoxFe2-xP nanoparticles (0 ≤ x ≤ 2), Co2-xMnxP …

Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel

Wayne State University Dissertations

Clinically available treatments are insufficient to achieve full functional recovery in large (>3cm) peripheral nerve injuries (PNI). The objectives in this thesis were 1) to study often overlooked elements of intrinsic PNI repair including release of inhibitory CSPGs and post-injury responses of inflammatory macrophages and dedifferentiated Schwann cells; 2) to create biomaterial scaf-folds featuring topographical and adhesive cues to enhance neurite outgrowth; and 3) to test the ability of those cues to direct macrophages and Schwann cells towards a pro-regenerative phe-notype. It is hypothesized that recapitulating the positive and negative cues of the PNI microenvi-ronment can better improve regeneration. …

Dielectric Anomalies Of Both Chiral And Achiral Nematogens Near The Isotropic To Mesogenic Phase Transition, Garrett Justin Godfrey

Wayne State University Dissertations

The dielectric properties of nematic liquid crystals were studied in both the achiral and chiral limits. For achiral nematics, the literature documents that pretransitional curvature occurs for polar molecules on both sides of the nematic and isotropic phase transition. This curvature is due to anti-parallel dimer formation. However, past models have failed to quantitatively describe pretransitional curvature. Through a generalization of the order parameter, a macroscopic model has been developed to mathematically describe the pretransitional curvature on the isotropic side of the transition. The new model was fitted to dielectric data from the literature. Meaningful parameter estimates were extracted.

The …

Bio-Inspired Synthesis Of Nanostructured Materials On Substrates For Environmental And Energy Applications, Xinghua Meng Meng

Wayne State University Dissertations

It is still a challenging task to develop simple methods for facile synthesis of functional nanostructures on substrates under mild conditions without using expensive instruments. We have successfully developed a bio-inspired method using simple diaphragm-assisted system to synthesize functional nanostructures on various substrates under mild conditions. We have systematically studied the effects of experimental parameters on the formation of nanostructures under controlled conditions. The fundamental mechanism involved has been systematically studied and revealed. By growing the unique networks of nanostructures on a piece of substrate, a double-rough surface, with structures at both nanoscale and microscale, has been achieved, showing interesting …

Substrate Effects And Dielectric Integration In 2d Electronics, Bhim Prasad Chamlagain

Wayne State University Dissertations

The ultra-thin body of monolayer (and few-layer) two dimensional (2D) semiconducting materials such as transitional metal dichalconiges (TMDs), black phosphorous (BP) has demonstrated tremendous beneficial physical, transport, and optical properties for a wide range of applications. Because of their ultrathin bodies, the properties of 2D materials are highly sensitive to environmental effects. Particularly, the performance of 2D semiconductor electronic devices is strongly dependent on the substrate/dielectric properties, extrinsic impurities and absorbates. In this work, we systematically studied the transport properties of mechanically exfoliated few layer TMD field-effect transistors (FETs) consistently fabricated on various substrates including SiO2,Parylene –C, Al2O3, SiO2 modified …

New Chemistry For The Growth Of First-Row Transition Metal Films By Atomic Layer Deposition, Joseph Peter Klesko

Wayne State University Dissertations

Thin films containing first-row transition metals are widely used in microelectronic, photovoltaic, catalytic, and surface-coating applications. In particular, metallic films are essential for interconnects and seed, barrier, and capping layers in integrated circuitry. Traditional vapor deposition methods for film growth include PVD, CVD, or the use of plasma. However, these techniques lack the requisite precision for film growth at the nanoscale, and thus, are increasingly inadequate for many current and future applications. By contrast, ALD is the favored approach for depositing films with absolute surface conformality and thickness control on 3D architectures and in high aspect ratio features. However, the …

Engineering Gold Nanoparticles And Their Use To Control Nucleation, Pedram Jahanian

Wayne State University Dissertations

This study focuses on fabrication of hybrid nanostructures using gold nanoparticles (AuNP) as seeds and partially oxidized potassium tetracyanoplatinate, known as Krogmann’s salt (KCP), and later this method will be employed to manufacture a prototype sensor for detecting different vapors. Nanocrystals are synthesized using electrochemical method with the aim to have more control over the size and shape of the charge transfer salt based on the seed mediated nucleation method. AuNP seeds are prepared on highly ordered pyrolytic graphite (HOPG) substrate by the electrocrystallization method. An aqueous solution of 0.05 to 1 mM Hydrogen tetrachloroaurate (HAuCl4) with 0.1 mM (Potassium …

Dendrimer Nanoconjugates And Their Oral Inhalation Formulations For Lung Cancer Therapy, Qian Zhong

Wayne State University Dissertations

Lung cancers are leading cause of cancer death for both men and women in the world. Lungs are also one of the primary organs to which almost all cancer can spread. Chemothepray plays a crucial role in the fight against both primary lung cancers and lung metastases. Doxorubicin (DOX) is a potent anticancer drug that has been approved for treating many cancers including lung cancers. However, only a few percent of systemically administered DOX can be found in the lungs. The issue is further complicated by dose-limiting toxicity of DOX. Another major challenge in the use of DOX is its …

Multiferroicity In Iron Vanadate, Magnetite And Polyvinylidene Fluoride Nanocomposite Films, Ehab Hamdy Abdelmonaim Abdelhamid

Wayne State University Dissertations

With the increasing demand on cheaper and better performance multifunctional materials for different applications, it is becoming more crucial to have a better understanding of the physics needed to tailor more devices and materials to fit better in every day’s technological needs. Materials which show more than one ferroic order simultaneously –namely, multiferroics– are of particular importance for their potential applications as multiple state memory elements, transducers and electrically tunable microwave devices.

In this work, we studied FeVO4 single crystals as an example on low symmetry multiferroics. We focused on the anisotropy in those crystals in an attempt to nail …

Static And Dynamic Behavior Of Carbon Fiber Reinforced Aluminum (Carall) Laminates, Gurpinder Singh Dhaliwal

Wayne State University Dissertations

STATIC AND DYNAMIC BEHAVIOUR OF CARBON FIBER REINFORCED ALUMINUM (CARALL) LAMINATES

by

GURPINDER SINGH DHALIWAL

Advisor: Dr. Golam Newaz

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The main aim of this research work was to investigate the static and dynamic properties of carbon fiber reinforced aluminum laminates cured without using any external adhesive and acid treatment of aluminum layers. A comprehensive study was undertaken to study the effect of adding epoxy resin rich polyester synthetic surface veil cloth layers on the failure modes and flexural and tensile response of these fiber metal laminates (FMLs). The main purpose of adding veil …

Novel Design And Synthesis Of Structured Iron Oxides For Battery Applications, Jian Zhu

Wayne State University Dissertations

Lithium-ion batteries (LIBs) are currently the dominant powder source for personal computers and portable electronics. LIBs also play important roles in larger-scale applications, including electric drive vehicles (EVs, HEVs) and grid-energy storage. To meet the increasing demand for energy storage, it is very urgent and crucial to develop next-generation LIBs using alternative electrode materials. For example, carbon is still exclusively used as anode materials in current LIBs. However, the theoretical capacity of graphite (372 mA h g–1 based on LiC6) has almost been achieved, and it becomes one of the bottlenecks to further increase the energy density of LIBs based …

Rheology Of Cross-Linked Polymers And Polymer Foams: Theory And Experimental Results, John Herman

Wayne State University Dissertations

Typical polymers have a time-dependent response to loading which results in stress relaxation or creep. Models using springs/dashpots or Volterra integrals are capable of predicting the material response, but place little or no emphasis on the reasoning behind the response. This research proposes a microscopic reasoning behind polymer chain movement, while developing a model to predict the creep and stress relaxation of a polymer foam. Based on the theorized slip/stick of polymer chains as they slide past each other, this model successfully predicts the behavior of a PMI polymer foam under tensile loads. This model lends insights into polymer microscopic …

Development Of Scaffold Architectures And Heterotypic Cell Systems For Hepatocyte Transplantation, Dalia Alzebdeh

Wayne State University Dissertations

In vitro assembly of functional liver tissue is needed to enable the transplantation of tissue-engineered livers. In addition, there is an increasing demand for in vitro models that replicate complex events occurring in the liver. However, tissue engineering of sizable implantable liver systems is currently limited by the difficulty of assembling three dimensional hepatocyte cultures of a useful size, while maintaining full cell viability, an issue which is closely related to the high metabolic rate of hepatocytes. In this study, we first compared two designs of highly porous chitosan-heparin scaffolds seeded with hepatocytes in dynamic perfusion bioreactor systems. The aim …

Development Of High Strength High Toughness Third Generation Advanced High Strength Steels., Codrick John Martis

Wayne State University Dissertations

Third generation advanced high strength steels (AHSS's) are emerging as very important engineering materials for structural applications. These steels have high specific strength and thus will contribute significantly to weight reduction in automotive and other structural component. In this investigation two such low carbon low alloy steels (LCLA) with high silicon content (1.6-2wt %) has been developed. These two steel alloys were subjected to single step and two step austempering in the temperature range of 260-399oC to obtain desired microstructures and mechanical properties. Austempering heat treatment was carried out for 2 hours in a molten salt bath. The microstructures were …

Development And Application Of Biomimetic Electrospun Nanofibers In Total Joint Replacement, Wei Song

Wayne State University Dissertations

Failure of osseointegration (direct anchorage of an implant by bone formation at the bone-implant surface) and implant infection (such as that caused by Staphylococcus aureus, S. aureus) are the two main causes of implant failure and loosening. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. A better understanding of the key factors that influence cell fate decisions at the bone-implant interface is required. Our study is to develop a class of "bone-like" nanofibers (NFs) that promote osseointegration while preventing …