Engineering Commons^™

Evaluate Deployment Of Photovoltaic Systems For Disasters, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

In 1996, the U.S. Department of Energy (DOE), developed a program with the Federal Emergency Management Agency (FEMA) to provide photovoltaic electrical power in disasters. In support of this effort, DOE purchased eight PV-generator trailers which were constructed in 1998 and supplied to FEMA for deployment in disaster response efforts. This report describes past and present use of the trailers, their depot location, list maintenance data, and the viability of the trailers in a disaster.

Design And Analysis For Melt Casting Metallic Fuel Pins Incorporating Volatile Actinides: Quarterly Report 5/15/01-8/15/01, Yitung Chen, Darrell Pepper, Randy Clarksean

Fuels Campaign (TRP)

No abstract provided.

Disclination Loop Behavior Near The Nematic-Isotropic Transition, Nikolai V. Priezjev, Robert A. Pelcovits

Mechanical and Materials Engineering Faculty Publications

We investigate the behavior of disclination loops in the vicinity of the first-order nematic-isotropic transition in the Lebwohl-Lasher and related models. We find that two independent measures of the transition temperature, the free energy, and the distribution of disclination line segments, give essentially identical values. We also calculate the distribution function D(p) of disclination loops of perimeter p and fit it to a quasiexponential form. Below the transition, D(p) falls off exponentially, while in the neighborhood of the transition, it decays with a power-law exponent approximately equal to 2.5, consistent with a “blowout” of loops at the transition. In a …

California Launch Vehicleeducation Initiative, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "California Launch VehicleEducation Initiative" from August 29, 2001.

Characterization And Electrochemical Investigation Of Boron-Doped Mesocarbon Microbeads Anode Materials For Lithium-Ion Battery, Mao-Hui Chen, Guo-Tao Wu, Guang-Ming Zhu, Jin-Kua You, Zu-Geng Lin

Journal of Electrochemistry

The anodic performances of boron doped and undoped mesocarbon microbeads(MCMBs) were comparatively studied and the structures were characterized by XPS, SEM, XRD and electrochemical measurements. It was found that boron doping samples greatly increased the degree of graphitization and the crystallite size, leading to quite different morphology. Electrochemical discharge/charge cycle tests indicate that lithium intercalation occurred at a little higher potential for the boron doped MCMBs, being attended by greater irreversible capacity loss.

Microstructure And Electrochemical Properties Of The Melt-Spinning Zr0.9Ti0.1(Ni, Co, Mn, V)2.1 Alloy, Ming-Fen Wen, Yu-Chun Zhai, Lian Chen, Min Tong, Hua Zhen, Rong-Jun Ma

Journal of Electrochemistry

The microstructure and electrochemical properties of Zr_0.9Ti_0.1(Ni,Co,Mn,V)_2.1 alloys prepared by both the melt-spinning method and the conventional induction melting were investigated. XRD studies show that Zr_0.9Ti _0.1(Ni,Co,Mn,V)_2.1 alloys at as-cast, melt-spinning and annealing are all face center cubic structure with C₁₅ laves phase, the higher the melt-spinning rate, the more the amorphous content. The electrochemical measurements show that melt-spinning alloys have better active behavior, low discharge capacity (< 280 mAh/g); but after annealed, the alloys are activated completely with 30 cycles, the capacities about 340 mAh/g are higher than those of as-cast and melt-spinning alloys; the annealec alloys have a better cycle stability than that of as-cast alloy, and the higher the melt-spinning rate is, the more stable the alloy becomes; at 300 mAh/g current density, the capacity of annealed 40 m/s alloy is up to 85% of the maximum capacity after 800 cycles, the capacity decay rate is about 6.9%.

Charge/Discharge Characteristics And Structural Changing Of Spherical β-Ni(Oh)2 Prepared From Different Nickel Salt, Shu-Ting Yang, Yan-Hong Yin, Hong-Jun Chen, Jun-Hua Jia, Ming-Chum Zhang, Li Ding

Journal of Electrochemistry

Spherical β-Ni(OH)₂ was prepared from different nickel salt by homogeneous complexing precipitation method. Its charge/discharge and cyclic voltammetry properties were studied. The authors found that there are many differences in the electrochemical properties of the prepared Ni(OH)₂.The specific capacity, cycling life and the discharging plateau of the material prepared from NiSO₄ were superior to those of the material prepared from Ni(NO₃)₂. The reasons of the differences were analyzed by XRD and FTIR measurements, which will become abasis for the selection of raw materials.

In Situ Ftir Reflection Spectroscopy Of Bioelectrode, Sa-Ying Dong, Guang-Yu Zhao, Yuzhu Gao, Guang-Zhang Chen, Ming-Xiang Lv

Journal of Electrochemistry

In situ FTIR reflection spectroscopy was used to study mediated enzyme electrode and immunoelectrode. We determined and analyzed IR characteristic spectra of GOD and glucose by the use of potential difference spectra and single beam subtractive spectra. At last, we explored the IR absorption characters of enzyme-immunoelectrode.

The Influence Of Membrane Resistance On The Electrochemical Behavior Of Gold Electrode Modified By Self-Assembled Monolayer, Xiao-Li Cui, Zhi-Yu Jiang

Journal of Electrochemistry

The electrochemical behavior of gold electrode modified by hexadecanethiol self-assembled monolayer (SAM) in the solution of Fe(CN)₆^3-/Fe(CN)₆^4- was investigated by cyclic voltammetry and ac impedance spectroscopy. The pinhole-free SAM-modified gold electrode has excellent blocking properties to the interfacial electron transfer from redox couple in solution to the substrate. The current increased exponentially with the overpotential at the high potential region. A good linear relationship between ln(I/η) and η_1/2 was observed. A model system Au/SAM/Hg was constructed and its I～V curve was measured. Similar phenomena were observed. There was also a linear relationship between ln(I/V) …

Codeposition And Corrosion Resistance Of Nickel-Cerium-Phosphorus Amorphous Alloys, Jiang Liu, Xiong Jiang, Lin-Cai Jiang, Ze-Shan Zhu

Journal of Electrochemistry

The possibility of electrodeposition of rare earth alloys from aqueous bath was investigated using varous techniques such as linear potential sweeping, cyclic voltammetry, electrodepositon at constant potential etc. The Ni-Ce-P alloys with different cerium content were electrodeposited from a weakly acidic solution containing CeCl₃, NaH₂PO₂ and so on the crystal structure and component were characterized by XPS, AES, XRD and SEM observation. The codeposits were found to be more highly corrosion resistent than that of Ni-P amorphous alloys by measuring polarization resistance and corrosion potential. The effects of codeposition conditions on the corrosion resistance were …

Current Oscillations In The System Of Carbon Steel/Phosphoric Acid/Platinum, Shao-Yuan Shi, Jin-Ping Wu, Jing Liu, An Lin

Journal of Electrochemistry

The periodic,aperiodic, chaotic and mixed-mode oscillations can occur in the process of the anodic electrodissolution of carbon steel in the solution of dilute phosphoric acid. More plentiful dynamic behaviors can be found in this system compared with the system of Fe/H₃PO₄/Pt.

The Activation Mechanism Of Al Alloys With Tin And Gallium In Alkaline Electrolytes, Zhen-Ya Li, Ling Yi, Zhi-Hui Liu, Lin Yang, Jing-Xin Su, Yan-Ying Chen

Journal of Electrochemistry

The major reason for Al-anode's activation is that Ga and Sn deposit on the aluminum surface and form activated points. The Al-Sn and Al-Ga binary alloys can't be activated in alkaline medium. During the dissolution of the Al-Sn-Ga ternary anode, Sn and Ga dissolve into the solution and transform into ions. After the Sn ions deposit on the surface of Al-anode, the Ga ions will deposit on Sn. The higher activation of the polynary alloy anode is caused by much more new activated points composed of Ga-Sn alloy being continually formed. Ga- Sn alloy with low melting point deposited on …

Determination Of Hydrogen Diffusion Coefficient In Metal Hydride Electrode With Electrochemical Impedance Spectroscopy, Xian-Xia Yuan, Nai-Xin Xu

Journal of Electrochemistry

Electrochemical impedance spectroscopy was employed to determine the hydrogen diffusion coefficient in MlNi _3.75Co _0.65 Mn_0.4Al_0.2 metal hydride electrode with various states of charge (SOC) at room temperature and with 50% SOC at various temperatures. It was found that hydrogen diffusion coefficient in this electrode decreases with the increase in SOC at ambient temperature, and for the electrode with 50% SOC, hydrogen diffusion coefficient increases with the increase of temperature and the activation energy for hydrogen diffusion in it is 35 kJ/mol.

Electrochemical Impedance Spectroscopy Study On A3 Steel In Anti-Corrosive Pigment Extract Solution, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su, Wen-Yun Hu, Yan-Zhen Chen

Journal of Electrochemistry

The corrosion behaviors of A₃ steel in different pH, 3.5%NaCl, modified zinc phosphate and aluminum triphosphate extract solutions have been studied by EIS. Results show:(a) The resistance increases with the increase of pH value under the same circumstances, but the capacity is the reverse. (b) Zinc phosphate, because of its low solubility, shows no inhibitive performance for A₃ steel in 3.5% NaCl extract solutions. (c) Aluminum triphosphate has good inhibitive performance for A₃ steel in 3.5% NaCl extract solutions at a pH of 6, probably because the triphosphate ion can complex with the corrosion-product, such as ferric …

A New Method For Impregnating Nafion Solution Into The Electrode Of Pemfc, Qian Tang, Ming Han, Bao-Lian Yi, Zhi-Yin Lin

Journal of Electrochemistry

We have developed a new method for impregnating Nafion solution into the catalyst layer of homemade hydrophobic electrode using capillary process. Those electrodes show better performance and higher utilization of catalyst (detected by CV and TEM) than traditional spray method in PEMFC. According to the results of SEM photograph and linear-analysis of sulfur and platinum for the electrode cross-section, we can conclude that the resin is uniform in the catalyst layer and has almost same depth as catalyst in the impregnated electrode. While in traditional method resin is not uniform in the catalyst layer and penetrates into the diffusion layer, …

Immobilization Of Long-Strand Dna Onto Gold Surface And Electrochemical Labeling Of Hybridization Of Dna, Jian-Zhang Zhou, Ling-Ling Wu, Li-Qin Dong, Zhong-Yu Lin, Jia-Wei Yan, Ping Dong, Yue Bao, Zhong-Hua Lin

Journal of Electrochemistry

Poly(diallyldimethylammonium chloride)(PDDA) was used to facilitate long strand DNA immobilization onto gold surface using self assembly method. Characterization of the PDDA self assembled film and subsequently immobilized DNA were carried out by Diffuse Reflectance Infrared, XPS, STM and electrochemical measurements. Hybridization of DNA was labeled by electrochemical method.

The Coulostatic Method For Evaluating Corrosion In Reinforced Concrete, Yong-Tao Zhao, Jian-Hua Wu, Chang-Jiu Zhao

Journal of Electrochemistry

In the present paper, the application of the coulostatic method to the corrosion of steel in concrete was reviewed. By comparing with other electrochemical techniques, the results obtained in the previous work reveal that the coulostatic method is an interesting alternative to the usual procedures for estimation of corrosion rate, and is better than them in some respects. The main advantages are as follows. The signal to be used can be instantaneous and as small as desired, so the electrode is minimally perturted during the measuring process. In addition, it is as rapid and quantitative, and at least as reliable …

Electrode Modification Using An Unzippable Polymer Paste, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A paste is described for capping electrodes with an oxide free metal layer incorporating a solvent, an unzippable polymer and particles. The electrode could be an interconnect such as a C4 bump. A method for forming a coating and for testing integrated circuit chips is also described. The invention overcomes the problem of interconnecting Pb containing electrodes that are covered with an insulating oxide on integrated circuit chips by coating the Pb containing electrode with Au to provide an oxide free surface for testing and interconnection.

Anisotropy Of Conducting P States And 11B Nuclear Spin-Lattice Relaxation In Mg1-XAlXB2, Kirill D. Belashchenko, Vladimir B. Antropov, S.N. Rashkeev

Nebraska Center for Materials and Nanoscience: Faculty Publications

We calculated the nuclear spin-lattice relaxation rate in the Mg_1-xAl_xB₂ system and found that the orbital relaxation mechanism dominates over the dipolar and Fermi-contact mechanisms in MgB₂, whereas in AlB₂ due to a smaller density of states and strong anisotropy of boron p orbitals the relaxation is completely determined by Fermi-contact interaction. The results for MgB₂ are compared with existing experimental data. To validate the theory, nuclear resonance experiments for the studied diboride alloy system are needed.

Optimization Of Real-Time Protocols For Wireless Packet-Switched Multimedia Networks Based On Partially Observed Multivariate Point Processes, William S. Hortos

Electrical Engineering and Computer Science Faculty Publications

Next-generation wireless networks have been designed to transport integrated multimedia services based on a cellular extension of a packet-switched architecture using variants of the Internet protocol (IP). Each call, arriving to or active within the network, carries demand for one or more services in parallel, where each service type has a guaranteed quality of service (QoS). Admission of new calls to the wireless IP network (WIN) from the gateway of a wired network or from a mobile subscriber (MS) is allowed by call admission control (CAC) procedures. MS roaming among the nodes of the WIN is controlled by handoff procedures …

Falconsat - 1: Design - Lessons Learned - How We Built A Satellite In 6 Months, Jim White

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Jim White titled "Falconsat - 1" from August 25, 2001.

Wku Capital Construction Update, Wku Board Of Regents

Board of Regents Documents

Presentation booklet regarding capital construction projects with photographs. Projects included:

• Glasgow Regional Postsecondary Education Center
• Elizabethtown Regional Postsecondary Education Center
• Media & Technology Center / Guthrie Tower & Plaza
• Science & Engineering Building
• Downing University Center Renovations
• University Boulevard Pedestrian Bridge

E.A. Diddle Arena Project, Wku Board Of Regents

Board of Regents Documents

Presentation booklet regarding Diddle Arena renovation project financing through bond issue. Includes contracts, revenue sources, insurance, deed descriptions and model procurement codes.

Cubesat: The Development And Launch Support Infrastructure For Eighteen Different Satellite Customers On One Launch, Robert J. Twiggs, Jordi Puig-Suari, Clark Turner

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professors Bob Twiggs, Jordi Puig-Suari, and Clark Turner titled "CubeSat: The Development and Launch Support Infrastructure for Eighteen Different Satellite Customers on One Launch" presented at the 15th Annual/USU Conference on Small Satellites on August 15, 2001.

The Crystallisation Of Glasses From The Ternary Caf2-Caal2si2o8-P2 O5 System, A. Clifford, R. G. Hill, Mark R. Towler, D. J. Wood

Chemical and Biochemical Engineering Faculty Research & Creative Works

A study of glasses from the ternary system CaF₂-CaAl₂Si₂O₈-P₂O₅ has been carried out. It has been shown that glasses with low phosphorus contents and high fluorite contents crystallise to fluorite. Fluorine reduces the glass transition temperature and is also required for the formation of fluorapatite (FAP). In the absence of fluorine in the glass no apatite phase is formed. Bulk nucleation of FAP is favoured for glasses with Ca:P ratios close to the apatite stoichiometry of 1.67 and with low crosslink densities. Thermal gravimetric analysis showed significant weight losses …

Modeling, Fabrication, And Optimization Of Niobium Cavities – Phase I: Quarterly Progress Report May 15, 2001 - August 15, 2001, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Multipacting is one of the major loss mechanisms in rf superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch compromising the optimal geometrical design. Past multipacting studies have not examined the impact of wall perturbations.

It is the purpose of this study to examine the chemical etching process in the design of niobium cavities so to maximize the surface quality of …

Analysis Of Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Dale L. Perry

Transmutation Sciences Materials (TRP)

The goal is to achieve a basic understanding of the corrosion of stainless steel by Lead Bismuth Eutectic (LBE), which has been proposed for use in the transmuter as both a coolant and as a sputtering target.

Pulsed Atomic Layer Epitaxy Of Quaternary Alingan Layers, J. Zhang, E. Kuokstis, Q. Fareed, H. Wang, J. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur

Faculty Publications

In this letter, we report on a material deposition scheme for quaternary Al_xIn_yGa_1−x–yN layers using a pulsed atomic layer epitaxy (PALE) technique. The PALE approach allows accurate control of the quaternary layer composition and thickness by simply changing the number of aluminum,indium, and gallium pulses in a unit cell and the number of unit cell repeats. Using PALE, AlInGaN layers with Al mole fractions in excess of 40% and strong room-temperature photoluminescence peaks at 280 nm can easily be grown even at temperatures lower than 800 °C.

Nuclear Criticality Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth, Pang Tao

Separations Campaign (TRP)

To mitigate the waste created by conventional fission reactors, spent nuclear fuel must be mechanically separated from its cladding. For the development of fuel processing technology to support the Advanced Accelerator Applications (AAA) Program, aqueous and pyrochemical processes will be used to further separate technetium and iodine, uranium and the higher actinides (see Figure 1 for an example of the process layout)1. The higher actinides, including plutonium, americium, curium, and neptunium will be separated from the waste to facilitate their fabrication into new fuel for placement in a transmuter. High-energy neutrons generated by spallation in the transmuter break down these …

Radiation Transport Modeling Of Beam-Target Experiments For The Aaa Project, William Culbreth

Reactor Campaign (TRP)

The AAA program will rely on the use of an accelerator-based transmuter to expose spent nuclear fuel to high-energy neutrons. The neutron flux will be sufficient to activate or fission the long-lived isotopes of Tc, I, Pu, Am, Cm, and Np that present a significant safety hazard in commercial spent fuel. Transmuter fuel will be subcritical and a high-energy proton accelerator is needed to maintain the necessary neutron flux through the use of a neutron spallation target. The maximum neutron energy produced by spallation (~ 600 MeV) is significantly higher than that produced by a commercial light water reactor (~ …