Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Aluminum (2)
- Cerium oxide nanoparticles (2)
- Diffusion (2)
- Intermetallics (2)
- Magnesium (2)
-
- X ray diffraction (2)
- Aa5083 (1)
- Adsorption (1)
- Aisi 304 stainless steel (1)
- Al (1)
- Ammonium perchlorate (1)
- Basalt fiber (1)
- Bile acids (1)
- Binary (1)
- Biosensor (1)
- Boltzmann matano (1)
- Capillarity (1)
- Carbon nanotube (1)
- Catalase activity (1)
- Catalyst (1)
- Cnf (1)
- Cnt (1)
- Composite (1)
- Concentrated solar power plants (1)
- Copper (1)
- Cryomilling (1)
- Cu (1)
- Cvd (1)
- Dextran (1)
- Diffusion barrier materials (1)
Articles 1 - 16 of 16
Full-Text Articles in Entire DC Network
First Principle Studies Of Cu-Carbon Nanotube Hybrid Structures With Emphasis On The Electronic Structures And The Transport Properties, Chengyu Yang
Electronic Theses and Dissertations
Carbon nanotubes have been regarded as ideal building blocks for nanoelectronics and multifunctional nanocomposites due to their exceptional strength, stiffness, flexibility, as well as their excellent electrical properties. However, carbon nanotube itself has limitations to fulfill the practical application needs: 1) an individual carbon nanotube has a low density of states at the Fermi level, and thus its conductivity is only comparable to moderate metals but lower than that of copper. 2) Metallic and semiconducting nanotubes are inherently mixed together from the synthesis, and the selection/separation is very difficult with very low efficiency. 3) Carbon nanotubes alone cannot be used …
The Study Of Photo-Reduction Of Cerium Oxide Nanoparticles In Presence Of Dextran: An Attempt In Understanding The Functionality Of The System, Swetha Barkam
Electronic Theses and Dissertations
Malignant melanoma cancer is the sixth common cancer diagnosed in the United States. Surgery, chemotherapy and radiation are some of the successful techniques in killing tumor cells. However, in these techniques, it is not easy to distinguish tumor cells from the healthy once which inadvertently get exposed to chemical agent/radiation. Therefore it is required to develop an anticancer agent which selectively kills the cancer cells, while still protecting the normal tissues. In our preliminary work, we have shown that Dextran (1000Da) coated Cerium oxide nanoparticles (Dex-CNPs) selectively kills the cancer cells (50% killing at a concentration of 150μM) without inducing …
Self-Assembled Two-Component Organic Tubes: Structures And Applications, Wenlang Liang
Self-Assembled Two-Component Organic Tubes: Structures And Applications, Wenlang Liang
Electronic Theses and Dissertations
Bile acids are physiologically important metabolites, which are synthesized in liver as the end products of cholesterol metabolism and then secreted into the intestines. They play a critical role in the digestion and absorption of fats and fat-soluble vitamins through emulsifications. The amphipathic and chiral nature of bile acids makes their unique building blocks for assembling supramolecular structures including vesicles, fibers, ribbons and hollow tubes. Lithocholic acid (LCA) is a secondary bile acid. Our studies show LCA can selfassemble into helical tubes in aqueous solution by the linear aggregation and fusion of vesicles. The objective of this dissertation is to …
Development Of Polymer Derived Sialcn Ceramic And Its Applications For High-Temperature Sensors, Gang Shao
Development Of Polymer Derived Sialcn Ceramic And Its Applications For High-Temperature Sensors, Gang Shao
Electronic Theses and Dissertations
Polymer-derived ceramic (PDC) is the name for a class of materials synthesized by thermal decomposition of polymeric precursors which excellent thermomechanical properties, such as high thermal stability, high oxidation/corrosion resistance and high temperature multifunctionalities. Direct polymer-to-ceramic processing routes of PDCs allow easier fabrication into various components/devices with complex shapes/structures. Due to these unique properties, PDCs are considered as promising candidates for making high-temperature sensors for harsh environment applications, including high temperatures, high stress, corrosive species and/or radiation. The SiAlCN ceramics were synthesized using the liquid precursor of polysilazane (HTT1800) and aluminum-sec-tri-butoxide (ASB) as starting materials and dicumyl peroxide (DP) as …
Corrosion Behaviour Of Aisi 304 Stainless Steel In Contact With Eutectic Salt For Concentrated Solar Power Plant Applications, Omar Ahmed
Electronic Theses and Dissertations
In response to the extensive energy demands on national and global levels, concentrated solar power (CSP) plants are designed to harness and convert solar energy to electricity. For such green energy application, robust, reliable and durable materials for CSP constructions are required. The corrosion resistance is among many parameters to consider in these thermalelectrical stations such as for pipes and storage tanks in CSP. In this investigation, the corrosion behavior of AISI 304 stainless steel (18 wt. % Cr, 8 wt. % Ni) with the heat transfer fluid, also known as solar salt, has been examined. The ternary eutectic salt …
Novel Nanostructures And Processes For Enhanced Catalysis Of Composite Solid Propellants, Robert Draper
Novel Nanostructures And Processes For Enhanced Catalysis Of Composite Solid Propellants, Robert Draper
Electronic Theses and Dissertations
The purpose of this study is to examine the burning behaviour of composite solid propellants (CSP) in the presence of nanoscale, heterogenous catalysts. The study targets the decomposition of ammonium perchlorate (AP) as a key component in the burning profile of these propellants, and seeks to identify parameters of AP decomposition reaction that can be affected by catalytic additives. The decomposition behavior of AP was studied in the presence of titanium dioxide nanoparticles in varying configurations, surface conditions, dopants, morphology, and synthesis parameters with the AP crystals. The catalytic nanoparticles were found to enhance the decomposition rate of the ammonium …
Barium Based Halide Scintillator Ceramics For Gamma Ray Detection, William Shoulders
Barium Based Halide Scintillator Ceramics For Gamma Ray Detection, William Shoulders
Electronic Theses and Dissertations
As our understanding of ceramic processing methods for the purpose of fabricating polycrystalline optical materials has increased over the past few decades, the race is on to bring ceramic technology to markets where single crystalline materials have traditionally been used. One such market is scintillators. This Master’s thesis focuses specifically on a class of materials attractive for use as gamma-ray scintillators. These barium based halides can potentially be utilized in applications ranging from ionizing radiation detection in the field to high-energy physics experimentation. Barium bromide iodide and barium chloride single crystals have already showed high light yield, fast scintillation decay, …
Interdiffusion Study Of Mg-Aa6061 System, Mian Fu
Interdiffusion Study Of Mg-Aa6061 System, Mian Fu
Electronic Theses and Dissertations
Magnesium (Mg) is a light-weight metal that has extraordinary physical and chemical properties for many potential applications in automobile, military, and electronics. Aluminum alloys, because of its light-weight, high strength and corrosion resistance have a wide range of commercial applications. Given these two, sometime competing, alloy systems, there are now many applications where the metallurgical compatibility of Mg- and Al-alloys are required for engineering applications. One such case is the development of diffusion barrier for U-Mo metallic fuel in Al-alloy cladding, where Mg, with its complete immiscibility with U and Mo is being considered as the diffusion barrier. While negligible …
Development And Characterization Of Nanoparticlee Enhancements In Pyrolysis-Derived High Temperature Composites, James Mckee
Development And Characterization Of Nanoparticlee Enhancements In Pyrolysis-Derived High Temperature Composites, James Mckee
Electronic Theses and Dissertations
Thermal protection systems, which are commonly used to protect spacecraft during atmospheric entry, have traditionally been made of materials which are traditionally high in manufacturing costs for both the materials needed and the manufacturing complexity, such as carbon-carbon composites and aerogels. [1] In addition to their manufacturing costs, these materials are also limited in their strength, such as PICA, in a way that necessitate the use of tiles as opposed to single structures because they are not capable of supporting larger structures. [2] The limitations of polymer reinforced composites have limited their entry into these applications, except for pyrolyzed composite …
Scandia And Ceria Stabilized Zirconia Based Electrolytes And Anodes For Intermediate Temperature Solid Oxide Fuel Cells: Manufacturing And Properties, Yan Chen
Electronic Theses and Dissertations
Mesoscale optical phenomena occur when light interacts with a number of different types of materials, such as biological and chemical systems and fabricated nanostructures. As a framework, mesoscale optics unifies the interpretations of the interaction of light with complex media when the outcome depends significantly upon the scale of the interaction. Most importantly, it guides the process of designing an optical sensing technique by focusing on the nature and amount of information that can be extracted from a measurement. Different aspects of mesoscale optics are addressed in this dissertation which led to the solution of a number of problems in …
X-Ray Scattering Investigations Of Metallic Thin Films, Andrew Warren
X-Ray Scattering Investigations Of Metallic Thin Films, Andrew Warren
Electronic Theses and Dissertations
Nanometric thin films are used widely throughout various industries and for various applications. Metallic thin films, specifically, are relied upon extensively in the microelectronics industry, among others. For example, alloy thin films are being investigated for CMOS applications, tungsten films find uses as contacts and diffusion barriers, and copper is used often as interconnect material. Appropriate metrology methods must therefore be used to characterize the physical properties of these films. Xray scattering experiments are well suited for the investigation of nano-scaled systems, and are the focus of this doctoral dissertation. Emphasis is placed on (1) phase identification of polycrystalline thin …
Interdiffusion And Impurity Diffusion In Magnesium Solid Solutions, Catherine Kammerer
Interdiffusion And Impurity Diffusion In Magnesium Solid Solutions, Catherine Kammerer
Electronic Theses and Dissertations
Magnesium, being lightweight, offers potential to be developed into extensive structural applications. The transportation segment has particular interest in Mg and Mg alloy for applications where reduced vehicle weight is proportional to increased fuel efficiency. Aluminum and zinc are two of the most common alloying elements in commercial Mg alloys. They improve the physical properties of Mg through solid solution strengthening and precipitation hardening. Diffusion plays a key role in the kinetics of and microstructural development during solidification and heat treatment. However, there is limited diffusion data available for Mg and Mg alloys. In particular, because Al is monoisotopic, tracer …
Development Of Nitrogen Concentration During Cryomilling Of Aluminum Composites, Clara Hofmeister
Development Of Nitrogen Concentration During Cryomilling Of Aluminum Composites, Clara Hofmeister
Electronic Theses and Dissertations
The ideal properties of a structural material are light weight with extensive strength and ductility. A composite with high strength and tailorable ductility was developed consisting of nanocrystalline AA5083, boron carbide and coarser grained AA5083. The microstructure was determined through optical microscopy and transmission electron microscopy. A technique was developed to determine the nitrogen concentration of an AA5083 composite from secondary ion mass spectrometry utilizing a nitrogen ionimplanted standard. Aluminum nitride and amorphous nitrogen-rich dispersoids were found in the nanocrystalline aluminum grain boundaries. Nitrogen concentration increased as a function of cryomilling time up to 72hours. A greater nitrogen concentration resulted …
High Volume Fraction Mg-Based Nanocomposites: Processing, Microstructure And Mechanical Behavior, Jinling Liu
High Volume Fraction Mg-Based Nanocomposites: Processing, Microstructure And Mechanical Behavior, Jinling Liu
Electronic Theses and Dissertations
Mg-based metal matrix nanocomposites (MMNCs) with mechanical properties, superior to those of coarse-grained composites, are promising structural materials for applications in the automotive and aerospace industries. The research in this area was primarily focused earlier on either micro-scaled reinforcements or nano-scaled reinforcements with very low volume fractions. MMNCs with high volume fractions have not been explored yet. In this research, we study the processing, microstructures and properties of MMNCs containing ceramic nanoparticles up to 30 vol.%. We first investigated the mechanical alloying of Al2O3 nanoparticles and pure Mg under high-energy ball milling conditions. The phase evolution and their distribution were …
Interdiffusion Reaction Between Uranium-Zirconium And Iron, Young Joo Park
Interdiffusion Reaction Between Uranium-Zirconium And Iron, Young Joo Park
Electronic Theses and Dissertations
U-Zr metallic fuels cladded in Fe-alloys are being considered for application in an advanced Sodium-Cooled Fast Reactor (SFR) that can recycle the U-Zr fuels and minimize the long-lived actinide waste. To understand the complex fuel-cladding chemical interaction of the U-Zr metallic fuel with Fe-alloys, a systematic multicomponent diffusion study was carried out using solid-to-solid diffusion couples. The U-10 wt.% Zr vs. pure Fe diffusion couples were assembled and annealed at temperatures, 630, 650 and 680°C for 96 hours. Development of microstructure, phase constituents, and compositions developed during the thermal anneals were examined by scanning electron microscopy, transmission electron microscopy and …
Tailoring The Properties Of Polyelectrolyte Coated Cerium Oxide Nanoparticles As A Function Of Molecular Weight, Shashank Saraf
Tailoring The Properties Of Polyelectrolyte Coated Cerium Oxide Nanoparticles As A Function Of Molecular Weight, Shashank Saraf
Electronic Theses and Dissertations
The application of Cerium oxide nanoparticles (CNPs) for therapeutic purposes requires a stable dispersion of nanoparticles in biological environment. The objective of this study is to tailor the properties of polyelectrolyte coated CNPs as a function of molecular weight to achieve a stable and catalytic active dispersion. This was achieved by coating CNPs with polyacrylic acid (PAA) which increased the dispersion stability of CNPs and enhanced the catalytic ability. The stability of PAA coating was analysed using the change in the Gibbs free energy computed by Langmuir adsorption model. The adsorption isotherms were determined using soft particle electrokinetics which overcomes …