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45th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 45th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 27-31, 2003.

Oscillatory Interlayer Exchange Coupling And Its Temperature Dependence In [Pt/Co]3/Nio/[Co/Pt]3 Multilayers With Perpendicular Anisotropy, Z. Y. Liu, Shireen Adenwalla

Materials Research Science and Engineering Center: Faculty Publications

Interlayer exchange coupling that oscillates between antiferromagnetic and ferromagnetic as a function of NiO thickness has been observed in [Pt(5 Å)/Co(4 Å)]₃/NiO(t_NiO Å)/[Co(4 Å)/Pt(5 Å)]₃ multilayers with out-of-plane anisotropy. The period of oscillation corresponds to ~2 monolayers of NiO. This oscillatory behavior is possibly attributed to the antiferromagnetic ordering in NiO. The antiferromagnetic interlayer exchange coupling for the 11 Å NiO layer shows an increase in coupling strength with increasing temperature, in agreement with the quantum interference model of Bruno for insulating spacer layers. A coexistence of exchange biasing and antiferromagnetic interlayer exchange coupling has …

Closely Linear Temperature Dependence Of Exchange Bias And Coercivity In Out-Of-Plane Exchange-Biased [Pt/Co] 3/Nio (11 Å) Multilayer, Z.Y. Liu, Shireen Adenwalla

Materials Research Science and Engineering Center: Faculty Publications

Strong out-of-plane exchange biasing has been observed in out-of-plane exchange biased [Pt (5 Å)/Co (4 Å)] ₃/NiO (11 Å) multilayer with perpendicular easy axis. Both the exchange field H_E and coercivity H_C display a closely linear temperature dependence except at very low temperatures. A thin NiO layer coated on the top of a Pt/Co multilayer has a great effect on the domain pattern of the Pt/Co multilayer, which is in a more irregular configuration with much smaller domain sizes than the uncoupled Pt/Co multilayer. A simulation according to Malozemoff's random field model gives a good agreement to …

Texture And Residual Stresses On Nanocomposite Coatings, Hussam E. Aikhasawneh

Masters Theses

Nickel was electroplated on cold-rolled 2024-T3 aluminum. The coating was done with reinforcement by nanoparticles of y-alumina or silicon carbide. For comparison, nickel-only coatings were done too. Rectangular samples were coated in nickel sulfamate bath with no particles to determine the optimum coating conditions. The optimized parameters were the current density, time of coating, and agitation rate. After coating conditions were established, composite samples were coated using these conditions. The coated layer was characterized by measuring: thickness, residual stresses, and crystallographic preferred orientation. The coated layer was tested by SEM for evaluation of the quality of the coatings. The presence …

Development Of Advanced High Temperature Heat Exchangers: Proposal, University Of Nevada, Las Vegas. Research Foundation

Publications (NSTD)

A research team led by the University of Nevada, Las Vegas (UNLV) Research Foundation proposes a project to develop advanced high temperature heat exchangers (HTHX) for hydrogen production and electrical energy conversion from advanced nuclear reactor concepts. This project will also support the development of Generation IV reactors. The research team includes researchers from UNLV, General Atomics (GA), Sandia National Laboratories (SNL), The University of California, Berkeley UCB) and Oak Ridge National Laboratory (ORNL).

The proposed project will be administered by the University of Nevada Las Vegas Research Foundation (UNLVRF). UNLVRF will provide the overall contract administration and is the …

Comment On: 'Depolarization Corrections To The Coercive Field In Thin-Film Ferroelectrics', Stephen Ducharme, Vladimir Fridkin

Stephen Ducharme Publications

The Letter by Dawber et al. [J. Phys.: Condens. Matter 15 L393 (2003)] notes that incomplete screening in the electrodes of a ferroelectric capacitor can result in an underestimate for the true coercive field in films of nanometer thickness. We show that their estimate of the magnitude of this correction it too large in the case of ferroelectric copolymer Langmuir- Blodgett films and, as a result, invalidates the claim that finite-size scaling of the ferroelectric coercive field is evident in films thinner than 15 nm.

Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day

Materials Science and Engineering Faculty Research & Creative Works

Processing, microstructure and property relationships in neodymium oxide doped high temperature superconducting YBa₂Cu₃O_7-x were investigated. It has been observed that a small amount (0.25–1 mol%) of Nd₂O₃ results in the formation of nanosized secondary phases which may have a significant effect on the superconducting properties of melt textured Y123 single crystals. It was further observed that addition of Nd₂O₃ greater than 1 mol% leads to multiple nucleation during solidification of Y123 and results in polycrystalline samples. Melt textured single crystals of Y123 with 1 mol% were successfully grown and …

Niti - Magic Or Phase Transformation?, Katherine C. Chen

Materials Engineering

NiTi alloys possess exciting properties and are staples in materials demonstrations. The shape memory effect and superelasticity property of NiTi fascinate people, but actually require significant materials knowledge to fully understand the phenomena. A laboratory dealing with phase transformations was thus developed to capitalize on the allure of NiTi for a junior/senior level “Thermodynamics and Kinetics of Materials” course. Students examine and characterize the shape memory and superelastic properties of NiTi wire, and then realize the difference is in the transformation temperature (i.e., Af - the austenitic finish temperature). They then use the phase diagram and TTT diagram to develop …

How We Learned To Love The Phase Diagram With A Ti-Cr Alloy Characterization Lab, Katherine C. Chen

Materials Engineering

While many students learn how to read and use a phase diagram in introductory materials courses, greater appreciation for such a tool can be garnered through the laboratory setting. A laboratory module for a “Structures of Materials” class (a “core class” for materials majors) has been developed to demonstrate the usefulness of phase diagrams, as well as, to emphasize the connections among processing, structure, and properties. Competence in determining stable phases, phase compositions, and mass fractions of phases are not the end goal, per se, but transpire since the skills are required to help solve a puzzle. Students are given …

Environment-Induced Degradation And Crack-Growth Studies Of Candidate Target Materials: Annual Progress Report (May 2002 – May 2003), Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

As indicated in the original proposal, the primary objective of this task is to evaluate the effect of hydrogen on environment-assisted cracking of candidate target materials for applications in spallationneutron- target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The materials selected for evaluation and characterization are martensitic stainless steels including Alloy HT-9, Alloy EP 823 and Type 422 stainless steel. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of these materials are being evaluated in aqueous environments of interest using tensile specimens under constant load and slow-strain-rate (SSR) conditions. …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Annual Progress Report (May 2002 – May 2003), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV) and Idaho State University (ISU) to evaluate the feasibility of determining residual stresses of welded, bent (three-point-bend), and cold-worked engineering materials using a new non-destructive technique based on positron annihilation spectroscopy. The proposed technique is the use γ-rays from a small MeV electron Linear accelerator (LINAC) to generate positrons inside the sample via pair production. This method can be used for materials characterization and investigation of defects in thick samples, which could not be accomplished by conventional positron technique or other non-destructive methods. The data …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Ii Final Report, Robert A. Schill Jr., Mohamed Trabia, William Culbreth

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 are the most appropriate shape for superconducting cavities. The need for very clean surfaces lead to the use of a buffered chemical polishing produce for surface cleaning to get good performance of the cavities. The second phase has resulted in an experimental setup of a fluid flow experiment with experimentation to be completed in the third year. Some of these results were presented at American Nuclear Society, Student Conference April 2-5, …

Neodymium Oxide Doped Melt Textured Yba2cu3o7-X Single Crystals, Fatih Dogan, Stephen W. Sofie, William C. Hicks, Michael Strasik, Kevin E. Mccrary, Arthur C. Day

Materials Science and Engineering Faculty Research & Creative Works

Processing, microstructure and property relationships in neodymium oxide doped high temperature superconducting YBa₂Cu₃O_7-x (Y123) were investigated. It has been observed that a small amount (/spl sim/ 0.25 - 1 mol%) of Nd₂O₃ results in the formation of nanosized secondary phases which may have a significant effect on the superconducting properties of melt textured Y123 single crystals. It was further observed that addition of Nd₂O₃ greater than 1 mol% leads to multiple nucleation during solidification of Y123 and results in polycrystalline samples. Melt textured single crystals of Y123 with < 1 mol% were successfully grown and characterized with respect to microstructural development and superconducting properties.

Effect Of Modified Clay-Zeolite Pigment On The Viscoelastic, Optical, And Printing Properties Of A Lwc Gravure Coating, Lokendra Pal

Masters Theses

This study investigates the influence of modified clay- zeolite pigment on the viscoelastic, optical, and printing properties of a LWC coating. Currently, lightweight, coated papers have experienced problems with mottle, distortion, fiber puffing and poor print quality when printed with water-based inks. However, water-based inks represent a proven solution to reducing volatile organic compound (VOCs) emissions. Poor wetting and ink spreading on the paper surface constitute the majority of print quality issues associated with the water-based printing of LWC papers.

Similar problems are encountered during the printing of ink jet papers due to high percentage of water contained in these …

Growth And Optical Properties Of Srbi₂Nb₂O₉ Ferroelectric Thin Films Using Pulsed Laser Deposition, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz

Mechanical and Aerospace Engineering Faculty Research & Creative Works

High quality SrBi2Nb2O9 ferroelectric thin films were fabricated on platinized silicon using pulsed laser deposition assisted with dc glow discharge plasma. Microstructure and ferroelectric properties of the films were characterized. Optical properties of the thin films were studied by spectroscopic ellipsometry and photoluminescence from the ultraviolet to the infrared region. Optical constants, n~0.56 in the infrared region and n~2.24 in the visible spectral region, were determined through multilayer analyses on their respective pseudodielectric functions. The band-gap energy is estimated to be 3.60 eV. A photoluminescence peak at 0.78 µm, whose intensity decreases with decreasing temperature, was observed when excited with …

Assessment Of The Readiness Of Egyptian Companies To Implement Business Process Reengineering Programs, Hany Waguih Shoukry

Archived Theses and Dissertations

Business Process Reengineering (BPR) emerged as a performance improvement methodology in 1990. Its objective of radical process redesign to achieve dramatic performance improvements makes it a potential candidate to be applied in most Egyptian companies, especially in the Egyptian private sector that is struggling to upgrade its performance in the new global economy. Although the main problem of BPR is its high probability of failure, which is due to the failure of companies to fulfill all BPR prerequisites, very limited research exists on how to measure the readiness of a company to implement successful BPR programs. The current research addresses …

The Localized Corrosion Behavior Of 6% Mo And 316l Stainless Steels In Chloride Media And The Effect Of Applied Mechanical Stress, Houssam El-Din Sabry Ahmed

Archived Theses and Dissertations

Electrochemical techniques were applied to study the crevice corrosion resistance of two types of stainless steel alloys namely, conventional 316L and super austenitic 6% Mo in acidified 3% NaCl solution at room temperature. Potentiodynamic results showed that 6% Mo alloy possessed a remarkable resistance to crevice corrosion compared to 316L alloy when tested in the same solution. The breakdown potential at which passivity broke down for 316L alloy was 0.00 m V, SCE, the corresponding value for 6% Mo alloy could not be reached up to the potential value of 700 m V, SCE. 316L alloy suffered extremely from crevice …

Quarterly Report For The Trp Project, March–June 2003, Samir Moujaes, Yitung Chen, Kanthi Kiran Daiska, Chao Wu

Transmutation Sciences Materials (TRP)

The MTL is assumed to be a 5m long rectangular loop with a circular cross-section. Because of the non-symmetry, and due to the active participation of the secondary flows due to the elbows present in the rectangular loop model, the geometry is considered as a 3D model.

When the regions of maximum corrosion and precipitation are compared, they fall in the same zone for both the analytical and simulated models. The reason for a larger concentration flux in the case of turbulent flow than for the laminar flow can be explained by the concept of higher lateral diffusion in the …

Students' Perceptions Of Both The Certainty And The Deterrent Effect Of Potential Consequences Of Cheating, Cynthia J. Finelli, Trevor S. Harding, Donald D. Carpenter, Honor J. Passow

Materials Engineering

No abstract provided.

Assessment Of The Performance Of Shape Memory Alloys As Implant Devices, Noura Ali Al-Khalifi

Theses

Shape memory alloys are one class of the family of smart materials. They are considered as biomaterials, since they are well accepted by the human body. One special feature of shape memory alloys (SMA) is their ability to revert to their previous shape. This material is deformed at low temperature and when it is heated, it returns (remember) to its original form. Although, the implant binary NiTi SMA is particularly successful as a biomaterial, our NiTi SMA consist of more that 50% (55.7%) of nickel. The main purpose of this thesis was to evaluate the biological response of the shape …

The Effectiveness Of Sacp In Controlling Of Concrete Steel Reinforcement In Aggressive Environments, Hassan Ali Abubaker Al Jafri

Theses

The Arabian Gulf is considered to be one of the world's most aggressive environments for reinforced concrete. Traditional methods of corrosion protection may not be enough to provide the required level of corrosion control for the design life of concrete structures in such environments.

Cathodic protection has been found as a viable technique of inhibiting chloride induced corrosion of steel in concrete structures. As an alternative to impressed current cathodic protection ICCP a remarkable developments recently have been made in the application of sacrificial anode cathodic protection as a means of enhancing the performance of patch repair.

The main objective …

Paints And Their Environmental Impacts On Human Health In The U.A.E, Masara Y. Al-Ameri

Theses

This thesis records the findings of a research program related to "Paints and Their Environmental Impacts on Human Health in the U.A.E". The study recommends attempt to find out what paint types are of a less harmful influence on human health within different building types in United Arab Emirates due to environmental conditions.

According to Larry W. Canter (1997) "Environmental Impact Assessment" can be defined as "the systematic identification and evaluation of the potential impact (effects) of proposed projects, plans, programs, or legislative actions relative to the physical- chemical, biological, cultural, and socioeconomic components of the total environment. The primary …

Effects Of Implementation Of Decaborane Ions In Silicon, Cheng Li

Dissertations

The next generations of Si microelectronic devices will require ultra shallow p-type junctions formed by implantation of B ions with energies below 1 keV, at which available beam currents are severely limited by space charge effects. To solve this problem, decaborane (B₁₀H₁₄) cluster ion implantation has been suggested as an attractive alternative to conventional B implants, because one decaborane ion implants ten B atoms simultaneously and each of the B atoms only carries approximately 1/11 of the total ion energy. Thus the same implantation depth and dose as with monomer B ions can be obtained using …

Process-Structure-Property Relationship Of A Mesogenic Bioerodible Polyarylate, Seung Uk Yoo

Theses

Polymeric biomaterials are artificially synthesized polymers designed for in-vivo use. The material must be characterized and should satisfy the requirements suitable in human bodies.

For the proper characterization of materials, it is essential to apply specific processes, analyze thermal and mechanical properties, and understand the process effect and the morphology. Thermal analysis is one of the most sophisticated and well developed techniques for polymer characterization. Turi [ 1 ] has explained about the thermal characterization of polymeric materials. Jaffe et al [2], in the chapters of characterization of fibers and films, emphasized the effect of the process history of a …

Ferromagnetic Domain-Wall Behavior During Reversal And Thermally Activated Antiferromagnetic Reversal In An Exchange-Biased Nio/Nife Bilayer, Z. Y. Liu, Shireen Adenwalla

Materials Research Science and Engineering Center: Faculty Publications

The magnetization reversal mechanism in an exchange-biased NiO/Ni₈₁Fe₁₉ bilayer has been investigated using the magneto-optic Kerr effect and magnetic force microscopy imaging. The asymmetric reversal along the unidirectional axis and the two-step reversal process along the hard axis are promoted by ferromagnetic domain-wall behavior in the decreasing and increasing field branches of the as-deposited hysteresis loop, which is strongly related to the exchange coupling at the interface and the distribution of orientation of the net magnetization at the interface carried by the antiferromagnetic domains. The temperature dependence of the exchange bias and coercivity shows the thermally activated …

A Bilayer Self-Assembled Membrane Electrode For Fluorescence And Its Electrochemical Characterization, Xiang-Ying Sun, Bin Liu, Yun-Bao Jiang

Journal of Electrochemistry

The bilayer membrane was assemblied on Au electrode by the electrostatic interaction between the fluorescence regent 1-naphthylamine diacetate acid (NADA) and DL-Cysteine. The SAMs electrode NADA/Cys/Au can be used as fluorescence and electrochemical sensor for metal ions. This paper states the electrochemical characterization of NADA/Cys/Au and SAMs' application in continous determination for Cu²⁺ and Ni²⁺.

The Electrochemical Behaviors Of A Novel Ferrocene Alkylthiol Sams On Au Electrode, Xiao-Gang Zhang, Yan-Li Shi, Hu-Lin Li

Journal of Electrochemistry

A novel alkylthiol molecule containing ferrocene and pyridium moieties and its hydrogenated products were synthesized and subsequently assembled on Au electrode as SAMs. Cyclic voltammogram(CV) was used to investigate the structure-dependent electrochemical response of the SAMs in 0.1 mol/L HClO₄ aqueous solution.

Oxidation Behavior Of Zr-Cu-Al-Ni Amorphous Alloys In Air At 300～500℃, H. H. Hsieh, W. Kai, T. G. Neih, Y. Kawamura

Journal of Electrochemistry

The oxidation behavior of the Zr- based bulk amorphous alloy (BMG; Zr-30Cu-10Al-5Ni in at.%) was studied in dry air over the temperature range 300～500 ℃. The kinetic results indicated that the amorphous alloy oxidized linearly at 300 ℃, while the parabolic oxidation was observed at 350～425 ℃, and the oxidation behavior at 500 ℃ was irregular and complicated. In general, the scales formed on the surface of the amorphous alloy were temperature-dependent, consisting of tetragonal-ZrO₂ at 300 ℃, and of mostly tetragonal-ZrO₂ as well as minor amounts of monoclinic-ZrO₂ and CuO at T ≥ 350 ℃.

Electrochemical Monitoring On The Deactivation Of A Metallic Oxide Anode, Li-Kun Xu, Shi-Zhe Song, Ting-Yong Wang, Guang-Zhang Chen

Journal of Electrochemistry

The process of accelerated life test of an IrO₂/Ta₂O₅ coated titanium anode was monitored using cyclic voltammetry and electrochemical impedance spectroscopy. The vatiation with electrolysis time of anodic voltammetric charge Q^*, the double layer capacitance C_dl,the oxide film resistance R_f and the charge transfer resistance R_ct for oxygen evolution was measured. A deactivation mechanism was proposed based on the observation results.

Synthesis And Electrochemical Characteristics Of Nickel-Based Complex Oxide LiANi0.78Co0.2Cd0.02O2, Rong-Zhong Yuan, Mei-Zhen Qu, Zuo-Long Yu

Journal of Electrochemistry

The nickel-based complex oxide Li_aNi_0.78Co_0.02O₂ cathode materials for lithium-ion rechargeable batteries was synthesized by the improved solid-state reaction method with LiOH·H₂O, ball-like Cd-doped Ni(OH)₂ and Co₂O₃ as raw materials. The analysis ICP-AES proved that the as-prepared compounds were near the stoichiometric form. The XRD, SEM and electrochemical characteristics testing were also carried out. The results showed that the complex cathode material Li_aNi_0.78Co_0.2Cd_0.02O₂ has layered structure, homogeneous surface distributions,uniform particles with good crystal morphology as well as stable electrochemical …