Materials Science and Engineering Commons^™

Infared Spectroscopy And Electrical Conductivity Of Copper(Ii) Cinnamate And Iodine-Doped Copper(Ii) Cinnamate, Kumar Krishnan

Student Works (2000-2009)

Copper(II) cinnamate (CC) was prepared from copper(II) acetate monohydrate and cinnamic acid. It was a light-blue powder. The Fourier Transform Infrared (FTIR) spectrum of CC, recorded as potasium bromide (K.Br) disc, indicated the presence of all bonds and functional groups expected of it and showed that it exist as an equal mixture of cis- and trans- isomers. The conductivity of CC at room temperature was 5.22 x 10⁻¹¹Scm⁻¹. It showed metallic behaviour in the temperature range 78-300 K, and its conduction mechanism obeyed Mott's variable range hopping (VRH) model in the same temperature range. The density of states at Fermi …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase I, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells and buffered chemical polishing produce good performance. The objective of the proposed research is to maximize the performance of the niobium cavities through studying multipacting, studying the effect of chemical etching on the surface roughness, and redesigning the cavities.

The US Congress has recently authorized exploring an alternative way to deal with spent nuclear fuel: Accelerator Transmuting of Waste (ATW). In this approach, a particle accelerator produces protons that react with …

Experimental Investigation Of Steel Corrosion In Lead Bismuth Eutectic (Lbe): Characterization, Species Identification, And Chemical Reactions, John Farley, Dale L. Perry

Transmutation Sciences Materials (TRP)

The goal of the present research is to achieve a basic understanding of corrosion of steels by Lead Bismuth Eutectic (LBE). Liquid LBE is under consideration in the transmuter as both a coolant and a target material. There have been studies of LBE, especially by the Russians, but a fundamental understanding and verification of its role in the corrosion of steels is still very 2 incomplete. Post-experiment testing and analysis will be performed on steel samples that have been in intimate contact with LBE. Chemical alterations and resulting chemical species will be measured at the steel surface. Techniques to be …

Magnetic Nanoparticles And Nanoparticle Assemblies From Metallorganic Precursors, Suresh Pillai, Yurri Gunko, David Mcinerney

Articles

No abstract provided.

Characterization And Soldering Of Organic Modified Aluminum Thin Films And Bond Pads, Rui Fang, Eric Dahlgren, Matthew O'Keefe, Thomas J. O'Keefe, Wu Sheng Shih, Daniel R. Gamota, Jie Zhang

Materials Science and Engineering Faculty Research & Creative Works

An immersion plating process using organic solutions was used to deposit a seed layer of copper and to activate the surface of thin film aluminum surfaces and bond pads. The seeded surfaces were subsequently electroless copper plated and tested for compatibility with soldering assembly. It was demonstrated that the copper particles deposited from the organic solution onto sputter deposited aluminum thin films were able to act as nucleation sites for the subsequent buildup of adherent, continuous copper films from conventional electroless plating baths. In addition, the metal deposition from organic solution process was found to be very selective on patterned …

Rms Titanic: A Metallurgical Problem, Hollis P. Leighly, B. L. Bramfitt, S. J. Lawrence

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Electrical Conductivity And Lattice Defects In Nanocrystalline Cerium Oxide Thin Films, Toshio Suzuki, Igor Kosacki, Harlan U. Anderson, Philippe Colomban

Materials Science and Engineering Faculty Research & Creative Works

The results of the electrical conductivity and Raman scattering measurements of CeO₂ thin films obtained by a polymeric precursor spin-coating technique are presented. The electrical conductivity has been studied as a function of temperature and oxygen activity and correlated with the grain size. When compared with microcrystalline samples, nanocrystalline materials show enhanced electronic conductivity. The transition from extrinsic to intrinsic type of conductivity has been observed as the grain size decreases to < 100 nm, which appears to be related to a decrease in the enthalpy of oxygen vacancy formation in CeO₂. Raman spectroscopy has been used to analyze the crystalline quality as a function of grain size. A direct comparison has been made between the defect …

Dynamics Of Polyacrylates In Concentrated Chloroform Solutions, Frank D. Blum, Raj B. Durairaj

Chemistry Faculty Research & Creative Works

The dynamics of polymers in polymer solutions have not been probed in great enough detail to provide a coherent picture of the behavior of these polymers, especially in more concentrated solutions. To help understand this behavior further, we have prepared a series of backbone-labeled polymers including poly(n-butyl acrylate)-d1 (PNBA). These provide a basis for comparison of the behavior among a group of related polymers. The dynamics have been probed by using deuterium relaxation times. Since the relaxation times are relatively fast and the quadrupolar relaxation mechanism is well understood, data from this technique provide a convenient means for comparison of …

Thermal Analysis Of Ultrathin Ps-R-Pmma Copolymer Films On Silica, Bing Zhang, Frank D. Blum

Chemistry Faculty Research & Creative Works

Composite materials represent a major part of man-made materials that are used in many applications. The interaction of polymers with surfaces plays a crucial role in the final properties of these materials and, by understanding the surface processes and adsorption mechanisms, better systems can be designed. Therefore, the behavior of polymer molecules at interfaces has been the topic of many studies in recent years and a rough picture has been obtained. Keddie et al. Obtained experimental results showing the dependence of the glass transition temperature (Tg) on the thickness of supported polystyrene films using ellipsometry. Later, they also investigated supported …

Preparation And Characterization Of Lithiated Cathode Materials For Lithium Batteries, Shanti Navaratnam

Student Works (2000-2009)

Four different cathode materials, LiNiO₂, LiCoO₂, LiCo₀.₂ Ni₀.₈O₂ and LiCo₀.₄, Ni₀.₆O₂ were synthesized by sol - gel technique. The prepared materials were characterized X-ray diffraction pattern, FT-IR and cyclic voltammetry. X-ray diffraction pattern shows crystallinity of materials, increases with higher calcination temperature. From FT- IR studies, it was shown, that the purity of sample also increased with prolong heating at higher temperatures. It was possible to obtain pure and highly crystalline LiNiO₂ after heating for fourteen hours at 800°c. Cyclic voltammetry shows the four prepared materials are suitable for fabrication of cathode, as lithium ions can intercalate and de-intercalate. LiNiO₂ …

The Effect Of Aluminium Oxide And Cerium Oxide As Dispersoids In Chitosan-Lithium Acetate Complexes, Hoi Mien Leow

Student Works (2000-2009)

In this study, chitosan with 85% deacetylation was used with Ni(OAc)₂·2H₂O as doping salt and Al₂O₃, or CeO₂ as dispersoid. They were mixed in certain weight percentages and dissolved in 100ml of 0.5% acetic acid solution. These solutions were poured into petri dishes and left at room temperature for film formation. Infrared Spectroscopy has shown that there is interaction between chitosan and LiOAc with and without dispersoid. The peaks are shifted. broadened. split and differs in intensity. The electrical conductivity of all samples was calculated using the bulk resistance value obtained from the complex admittance plot. The highest electrical conductivity …

Synthesis And Characterization Of Lithiated Mixed Metal Oxides For Lithium Ion Rechargeable Batteries, Seng Gee Tan

Student Works (2000-2009)

Lilhiated mixed metal oxides for lithium ion rechargeable batteries were prepared by the sol gel technique. Samples consisting of lithium acetate, nickel nitrate, cobalt nitrate, manganese acetate and aluminium fluoride were characterised using X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIRS). Energy Dispersive Analysis of X-rays (EDAX) w1d Cyclic Voltammetry (CV). Thermal characterization shows that the acetates, nitrates and fluorides of precursors material deform at temperature between 50° to 100°C and the products begin to form at a temperature between 264°C to 271°C. FTIR studies show that the materials must be heated for a longer time …

Sulphide Based Materials As Potential Anodes In Lithium Ion Cells, Azlin Sanusi

Student Works (2000-2009)

Sulphides based compounds PbS and SnS have been studied as possible anode material in lithium ion cell. PbS was prepared by the chemical bath deposition technique and SnS by the double decomposition method. Both samples were characterized by the powder X-ray diffraction technique and energy dispersive analysis of X-rays (EDAX). The room temperature electrical conductivity of PbS is 2.6 x 10⁻⁴ S cm⁻¹ and SnS is 5.3 x 10⁻⁷ S cm⁻¹ while at 90°C the electrical conductivity of PbS is 3.3 x 10⁻⁴ S cm⁻¹ and SnS is 2.90 x 10⁻⁶ S cm⁻¹ Cyclic voltammetry determined the potential anode ability …

Evidence Of Nanostructure In Multilayer Cdse Thin Films, Suganthi Devadason

Student Works (2000-2009)

Cadmium Selenide multilayer thin films have been prepared using physical vapour deposition method. Alternate layers of Cadmium and Selenium are deposited on unheated glass substrates. Morphological study of the samples has been done using SEM micrographs with a magnification of 5000. The EDX analysis gives the quantitative atomic percentage content of elements present in the samples. It is found that the high Cadmium content in the samples increased the crystallinity. From XRD measurements, it is evident that many films are polycrystalline in nature with a peak corresponding to < 111 > plane orientation of the zinc blende structure. The lattice constant of the …

An Investigation Of Eddy Current Analysis For Laser Surface Treatment Of Steel, Ronald Edward O'Meara

Dissertations and Theses @ UNI

The problem of this exploratory study was to determine the strength of the bivariate correlational relationship between microhardness readings converted to Rockwell values and eddy current values of laser heat-treated AISI 1045 steel. Further, the microstructure was analyzed to determine the microstructural changes formed by laser surface treatment utilizing a carbon dioxide laser.

The purpose of this study was to investigate the microhardness and depth of hardness formed by laser surface treatment, to develop a measure of correlation between microhardness and eddy current values, and to study microstructural changes formed by the laser surface treatment. This knowledge could be used …

Forecasting With Combined Seasonal Indiaces, Al-Nasser Essam Taki El Din

Archived Theses and Dissertations

No abstract provided.

Multimode Quantitative Scanning Microwave Microscopy Of In Situ Grown Epitaxial Ba1-XSrXTio3 Composition Spreads, K. S. Chang, M. Aronova, O. Famodu, I. Takeuchi, S. E. Lofland, Jason R. Hattrick-Simpers, H. Chang

Faculty Publications

We have performed variable-temperature multimode quantitative microwavemicroscopy of in situepitaxial Ba_1−xSr_xTiO₃ thin-film composition spreads fabricated on (100) LaA₁O₃ substrates. Dielectric properties were mapped as a function of continuously varying composition from BaTiO₃ to SrTiO₃. We have demonstrated nondestructive temperature-dependent dielectric characterization of local thin-film regions. Measurements are simultaneously taken at multiple resonant frequencies of the microscope cavity. The multimode measurements allow frequency dispersion studies. We observe strong composition-dependent dielectric relaxation in Ba_1−xSr_xTiO₃ at microwave frequencies.

Effects Of Compression Processing Parameters And Antioxidants On Molecular Degradation Of Biodegradable Poly-L-Lactide (Plla), Thomas J. Hannan Jr.

Masters Theses

The purpose of this research was to find a combination of poly (L-lactic acid), also known as poly-L-lactide or (PLLA) and antioxidants that would, together, produce a product whose degradation rate would be advantageous for use in biodegradable medical implants. Intrinsic viscosity tests were conducted on compression molded samples of PLLA that were molded at various processing parameters in order to find optimal parameters. The optimal processing parameters were found to be time 10 minutes, temperature 220°C, and pressure 1000 psi.

The molecular weight of PLLA sample was taken while pressure, time, and temperature were varied. As pressure increased, no …

Effect Of Electron-Attracting Groups On The Thermal Stability Of Subtituted Copper (Ii) Benzoate, Fauziah Kamaruddin

Student Works (2000-2009)

Copper(II) benzoate, copper(II) 4-fluorobenzoate, copper(II) 4-chlorobenzoate, copper(II) 4-bromobenzoate, copper(II) 4-iodobenzoate, copper(II) pentafluoro benzoate, copper(II) 4-nitrobenzoate and copper(II) 3,5-dinitrobenzoate are potential low dimensional thermally stable molecular electronics. The them1al properties of these samples are investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA reveals that copper(II) benzoate (CB) slowly decomposed at 243.5°C, losing 67.7% of its weight at 515°C. The DSC shows two endotherms separated by an exotherm. The first endotherm at 224°C may due to the breaking of bridging bond to give benzoyloxy radicals. The exotherm at 231°C may due to the formation of volatiles from the decomposition …

Effects Of Argon Dilution Of Silane On The Optical Properties And Surface Morphology Of Hydrogenated Amorphous Silicon, Choon Kheam Lim

Student Works (2000-2009)

Hydrogenated amorphous silicon (a.Si:H) was prepared using the d.c plasma grow discharge system. Two sets of samples were prepared and studied. The first set of samples referred to as the high argon dilution films were prepared from the discharge of pure silane at flow-rate of 5sccm and silane at the same flow-rate diluted in argon at flow-rates of 5, 10 and 15sccm. Similarly, the second set of sample referred to as the low argon dilution films were prepared from the discharge of pure silane at flow-rate of20sccm and silane at the same flow-rate diluted in argon at the flow-rates mentioned …

Characterization Of Lithium Intercalation Oxides Based On Manganese And Copper, Vengidason Seguprakash

Student Works (2000-2009)

In this study, several lithium intercalation compounds have been synthesized and characterized. Lithium manganese copper oxide cathode materials were prepared by sol gel method using tartaric acid as the gelating agent. Five types of cathode materials were synthesized. The sol gel technique has permitted the synthesis of manganese oxides that are capable of reversibly intercalating large amounts of lithium ions. To see the effect of adding copper to lithium manganese oxide several experiments were carried out. These include X-Ray diffraction to see whether the LiMn₂O₄ lattice has widened or collapsed. It was seen that LiMn₂O₄ and LiCu₂O₂ XRD patterns were …

The Effects Of Incorporation Of Polyethylene Glycol On Properties Of Silica-Carbon Black-Filled Rubber Compound, Yoke Cheng Tang

Student Works (2000-2009)

The use of polyethylene glycol (PEG) to modify the surface of precipitated silica by means of physical adsorption was investigated. The effects of adding PEG on processing, cure and physical properties of a silica-carbon black-filled natural rubber truck tread compound were examined. For each series of investigation, two sets of experiments were conducted. Set I was to check the effects of both physical adsorption due to PEG and chemical modification due to a silane coupling agent, Si-69 on the surface of silica. Set 2 was to check the effects of physical adsorption due to PEG alone on the surface of …

Comment On "Influence Of Fe³⁺/Fe2+ Ratio On The Crystallization Of Iron-Rich Glasses Made With Industrial Wastes", Chandra S. Ray, Mario Pelino, Alexander Karamanov

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Spontaneous, Non-Aqueous Electrochemical Deposition Of Copper And Palladium On Al And Al(Cu) Thin Films, R. Fang, H. Gu, Matthew O'Keefe, Thomas J. O'Keefe, W. S. Shih, K. D. Leedy, R. Cortez

Materials Science and Engineering Faculty Research & Creative Works

Copper and palladium seed layers have been successfully deposited from organic solutions onto patterned and unpatterned pure aluminum and Al (0.5%Cu) thin films using an immersion displacement process. The reaction occurs at ambient temperature and pressure by a spontaneous electrochemical mechanism. Copper and palladium deposition using the organic solution was studied as a function of reaction time and Cu or Pd concentration in the solution. It was found that both time and the initial ionic metal concentration significantly influence deposit morphology, particle size and shape, and adherence. Nucleation of Cu or Pd sub-micron particles on both Al and Al (Cu) …

Properties Of Sputtered Bilayer Wnx/W Diffusion Barriers Between Si And Cu, K. D. Leedy, Matthew O'Keefe, E. J. Dahlgren, J. T. Grant

Materials Science and Engineering Faculty Research & Creative Works

Copper interconnect metallizations in next generation integrated circuits will require thin diffusion barrier layers (< 20 nm) between the Cu and low-k dielectric which may also function as seed layers for subsequent material depositions. One possible structure entails a multicomponent diffusion barrier with a lower resistivity component, such as W on WNx. In this study, sputtered WNx/W bilayer thin films were investigated as diffusion barriers between Si and Cu. The total thickness of the WNx/W bilayer was fixed at 20 nm while the WNx thickness was varied from 0 to 20 nm. After deposition of the barrier films, a 100 nm thick Cu film was sputtered over the top of the ct-W and amorphous WNx bilayer. The as-deposited WNx/W film stress was found to be strongly dependent on the relative amount of WNx and W present and the addition of a Cu overlayer was found to mitigate the stress levels. The WNx/W barriers remained stable after 650°C anneals and exhibited phase transformations to W 2N. Microstructural characterization using transmission electron microscopy and x-ray diffraction and chemical analysis by x-ray photoelectron spectroscopy of the films were used to identify the as deposited and transformed phases. © 2001 Materials Research Society.

Development Of Transparent Lsco And Lscno Conductors For Optical Shutter Systems, Robert W. Schwartz, M. T. Sebastian, M. Charoenwongsa, H. D. Dobberstein

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We have prepared lanthanum strontium cobalt oxide (La0.50Sr0.50CoO3; LSCO 50/50) and lanthanum strontium cobalt nickel oxide (La0.50Sr0.50Co0.50Ni0.50O3; LSCNO) as candidate transparent electrodes for use in a shutter-based infrared sensor protection device. The shutter device requires that the electrode be transparent (80% transmission) and have moderate sheet resistance (300 Ω/sq.). Because of the effects of film thickness on intrinsic material properties, such as resistivity and extinction coefficient, and simple engineering issues (i.e., the relationship between film thickness, resistance and transmission), films of various thicknesses were prepared to achieve an optimal balance of electrical and optical performance. van der Pauw measurements and …

Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Poly(vinyl acetate) (PVAc) is an important polymer in applications because of both its bulk and surface characteristics. Its chain architecture gives it a low Tg and, generally, good qualities for processing and applications, which include paints, adhesives, thin films and surface coatings. In this study, we investigate the surface dynamics of PVAc absorbed onto silica with deuterium nuclear magnetic resonance (2H NMR). For dynamics studies, 2H NMR is an excellent technique because it uses an innocuous probe that can report on correlation times (τc) from approximately 10-8 s to 10 s. We report the use of two-dimensional exchange NMR (2D-X) …

Agglomerated Die Casting Lubricant, Mary R. Reidmeyer

Materials Science and Engineering Faculty Research & Creative Works

A lubricant for use in lubricating the shot sleeve of a machine for die casting molten metals is in the form of agglomerated particles. The particles have an inorganic high pressure lubricant agglomerated, with a binder material and with an organic material. The solid lubricant is resistant to dusting, caking and breakage, can be fed through an automatic dispensing machine, and combines inorganic and organic materials to achieve excellent lubrication properties. The product has low flash and low smoke release into the environment.

Chemical Plating Method, Electrolytic Cell And Automotive Oxygen Sensor Using It, Mary R. Reidmeyer, Matthew J. Donelon, Robert F. Killion

Materials Science and Engineering Faculty Research & Creative Works

An automotive lambda oxygen sensor is formed by electroless plating of a thin, catalytically active, conductive electrode uniformly on the outer surface of a zirconia thimble. The process includes forming a pristine zirconia solid electrolyte thimble and drilling out a cylindrical cavity in it. A porous outer surface suitable for producing crystallization sites is formed by dipping the unfired thimble in a zirconia slurry containing spray-dried microspheres and firing the coated thimble to densify the thimble and the microspheres and to produce cavities on the surface of the thimble. An inner platinum electrode is formed by conventional conductive ink painting …

Spectrally Selective, Matched Emitters For Thermophotovoltaic Energy Conversion Processed By Tape Casting, L. G. Ferguson, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The thermophotovoltaic (TPV) generator converts radiant energy from a high temperature emitter element into electric power using infrared responding photovoltaic cells. Spectral control is a primary issue in TPV applications. Conventional TPV generators have relied on filters to achieve selectivity and spectral control with near-blackbody ceramic emitters. Several practical problems have limited the success of this approach, particularly the present lack of a satisfactory wide-band infrared filter. A new, spectrally selective emitter is described in this work, and will be called the “bandgap matched” emitter because its emissive power spectrum is very efficiently matched with the infrared response of the …