Engineering Commons^™

Oxidation And Adsorption Of Deoxyribonucleic Acid At Highly Ordered Pyrolytic Graphite And Glass Carbon Electrode, Jianzhang Zhou, Lingling Wu, Jin Luo, Zhonghua Lin

Journal of Electrochemistry

It is shown that calf thymus DNA(CT DNA) can be adsorbed at highly ordered pyrolytic graphite(HOPG) electrode and detected by differential pulse voltammetry(DPV) and electrochemical atomic force microscopy(ECAFM). It is found that controlled potential pre-polarization influences largely the adsorption of dsDNA while it has little influence on ssDNA. It is demonstrated that ECAFM is useful to exploit adsorption of DNA at HOPGE. The pattern of adsorption of DNA at HOPG electrode that fits best with the experimental data is proposed. The results aslo shows that UV/Vis reflection spectroscopy, which has not been used in studying electrochemical behavior of DNA, is …

Oxidation Mechanism Of Hypophosphite, Dongbai Sun, Ying Jin, Hongying Yu, Dejun Yang

Journal of Electrochemistry

There exist two oxidation current peaks on the anodic polarization curve between -0.7 V and 0 V(SCE) in Na_hypophosphite solution. Peak Ⅰ (-0.55 V, SCE) , which represents the oxidation process from H 2PO - 2 to H 2PO - 3, has been studied previously. Peak Ⅱ, which is located at the potential about -0.4 V(SCE), is investigated emphatically in this paper. The results show that, peak Ⅰ and Ⅱ are corresponding to two successive steps in oxidation process of H 2PO - 2, i.e. peak Ⅱ corresponds to the oxidation process of adsorped (HPO 2) ads , an intermediate …

A Risk Analysis Of Remediation Technologies For A Doe Facility, Helene A. Wilson

Theses and Dissertations

The Department of Energy is responsible for selecting a remediation technology to clean up the Waste Area Group (WAG) 6 site at the Paducah Gaseous Diffusion Plant (PGDP) in Kentucky. WAG 6 is contaminated with an uncertain amount of trichloroethylene (TCE) and technetium-99 (Tc-99). Selecting a remediation technology involves a certain degree of risk because many of these technologies are new or proven only for a specific type of contaminant or a particular set of site conditions. Differences between contaminant type and site conditions are enough to make the performance of a remediation technology uncertain. This research identifies the technological …

Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Platinum Electrode In Alkaline Medium, S. N. R. Pakalapati, Branko N. Popov, Ralph E. White

Faculty Publications

The anodic oxidation of ethylenediaminetetraacetic acid (EDTA) was studied in alkaline medium on a smooth platinum electrode. Bulk electrolysis indicated that stable organic intermediates (formaldehyde and glyoxal) are formed during the oxidation of EDTA and that complete oxidation to CO₂ can be achieved. The proposed pathway suggests that the acetate groups in EDTA are initially oxidized, generating formaldehyde and ethylenediamine. The rest potential of EDTA (0.066 to 0.164 V vs. Hg/HgO) was observed to be higher than for other organic species. In alkaline medium, very little EDTA oxidation was found to occur on bare platinum. Limiting-current behavior due to …

Linear Algebra Used To Determine Independent Half‐Cell Equations, D. H. Coleman, Ralph E. White

Faculty Publications

No abstract provided.

The Oxidation Of Hydrogen Absotbing Alloys And Its Inhibition, Suqin Wang, Baojia Xia, Geping Yin, Pengfei Shi

Journal of Electrochemistry

This paper introduces the method to judge:1)the possibility of oxidation of themetal hydride electrode in an anode process by cyclic voltammetric curves,2)the oxidation pattern ofmetal hydride electrode in oxygen atmosphere in various charged states,and 3)the inhibition ofoxidation of hydrogen absorbing alloys by certain surface treatment.

Long-Term Effects Of Neutron Absorber And Fuel Matrix Corrosion On Criticality, William Culbreth, P. Zielinski

Mechanical Engineering Faculty Research

Proposed waste package designs will require the addition of neutron absorbing material to prevent the possibility of a sustained chain reaction occurring in the fuel in the event of water intrusion. Due to the low corrosion rates of the fuel matrix and the Zircaloy cladding, there is a possibility that the neutron absorbing material will corrode and leak from the waste container long before the subsequent release of fuel matrix material. An analysis of the release of fuel matrix and neutron absorber material based on a probabilistic model was conducted and the results were used to prepare input to KENO-V, …

Degradation Of Polymeric Biomaterials, Shalaby W. Shalaby, Russell A. Johnson, Meng Deng

Cells and Materials

Environmental and processing factors affecting the biostability of medical devices made from traditionally "stable" polymers, such as isotactic polypropylene (PP) and ultrahigh molecular weight polyethylene (UHMW-PE) , were analyzed and their undesirable degradation was related to performance of typical medical devices. Among the critical phenomena determining the biological performance of UHMW-PE and PP devices are oxidation during melt-processing and the propensity of the polymer chains to radiolyse and radio-oxidize. Polyesters and their biomedical devices , which can be designed to degrade predictably, are addressed with some focus on the less obvious determinants of performance.

The Self-Discharge Of The Niooh/Ni(Oh)2 Electrode Constant Potential Study, Z. Mao, Ralph E. White

Faculty Publications

Hydrogen oxidation currents at a NiOOH/Ni(OH)₂ electrode were measured directly at constant potentials for various hydrogen pressures and states of charge. It was found that the hydrogen oxidation current is linearly proportional to the hydrogen pressure at all electrode potentials and that the logarithm of the anodic current is a linear function of electrode potential. It was also found that hydrogen oxidation on the nickel substrate material was strongly inhibited by the presence of nickel hydroxide on the substrate surface. By comparing the currents for hydrogen oxidation and oxygen evolution on the NiOOH/Ni(OH)₂ electrode and on a nickel …

The Affects Of High Temperature Steps On Bow, Warp And Slip Of A Wafer, Mark Klare

Journal of the Microelectronic Engineering Conference

Bow, Warp and Slip measurements were used to characterize push/pull rates of a three inch oxidation furnace. The push/pull rates were varied from 3 to 30 inches per minute. To minimize the amount of bow, warp, and slip while still being time efficient, recommended push rates of 12 and pull rates of 3 in/mm should were found.

Investigation Of Locos Process Using Nitrogen Implantation, Joseph W. Walters

Journal of the Microelectronic Engineering Conference

A localized oxidation of silicon (LOCOS) process was investigated using nitrogen ion implantation. The doses of 2E12, 2E13, 2E14, and 1E15 atoms/cm2 were implanted through a photoresist mask using the Varian/Extrion 40-100 ion implanter. The results show the initial formation of a LOCOS oxidation. The localized image faded on extended oxidation which indicates the implanted region did not adequately inhibit the diffusion of oxygen.

Boron Solid Source Characterization, Kelly Baycura

Journal of the Microelectronic Engineering Conference

Standard Oil’s BN—975 planar diffusion sources were used to fabricate integrated resistors. Dopant transfer was done in a N2:02:H2 ambient at 975 C. Two methods of removing the crystal defect layer formed at the surface, low temperature oxidation (LTO) and a nitric acid soak, were evaluated. Successful layer removal was achieved with the LTO. The nitric acid soak met with limited success.

The Effect Of The Tribromide Complex Reaction On The Oxidation/Reduction Current Of The Br2/Br– Electrode, P K. Adanuvor, Ralph E. White, S. E. Lorimer

Faculty Publications

The Br₂/Br^– electrode reaction with tribromide complex formation reaction in the solution, a chemical-electrochemical (C-E) type reaction, has been investigated in order to determine the effect of the chemical reaction on the electrode kinetics. It is shown that the chemical reaction has little effect on the electrode kinetics at very slow homogeneous reaction rates, but has a more drastic effect on the electrode kinetics at faster homogeneous reaction rates. Also, the kinetics at the electrode are affected by changes in the concentrations of the active species (Br₂, Br^–, and Br₃^–) …

Kinetics Of The Oxidation Of Hydrazine By Iodine In Acidic Perchlorate Medium, Mohamed Ashraf Anis Onsy

Archived Theses and Dissertations

No abstract provided.

An Analysis Of A Back Fed Porous Electorde For The Br2/Br- Redox Reaction, John W. Van Zee, Ralph E. White

Faculty Publications

No abstract provided.

An Analysis Of A Back Fed Porous Electrode For The Br2/Br Reaction, John Van Zee, Ralph E. White

Faculty Publications

An experimental analysis of the Br₂/Br^– redox reaction in a porous back fed ruthenium-coated titanium electrode is described. A mathematical model of the steady-state process is presented. Nonlinear regression of the model against the experimental data gives physically meaningful parameter estimates; these parameters and the model provide a design equation for the porous electrode current as a function of specific surface area, bulk Br₂ concentration, average total overpotential, and the Reynolds number. The design equation shows that the back fed electrode could reduce the loss of Br₂ across the separator and the ohmic loss in …

The Characterization Of The Oxygen Transfer Capabilities Of Fermentors, Joseph Stephen Adamca

Theses

A method of characterizing the oxygen mass transfer capabilities of fermentors was developed where volumetric oxygen mass transfer coefficients are obtained using a modified sulfite oxidation method in conjunction with on line digital data processing. Carboxymethylcellulose is used in the reaction media to simulate the viscosity of typical non-Newtonian fermentation broths. Using this method, instantaneous values of volumetric oxygen mass transfer coefficients can be obtained for various combinations of agitation and airflow rates in different fermentor configurations. This data is useful in the scale up or scale down of fermentors.

Data obtained using this method have revealed that for a …

Determination Of Oxygen Chemical Diffusion Coefficients In Single Crystal Srtio By Capacitance Manometry, D. B. Schwarz, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The oxidation kinetics of a single crystal of SrTiOs were measured with a tensivolumetric system over the temperature range 700 -975 at 0.03 atm oxygen pressure. The oxidation was found to be oxygen diffusion limited with an activation energy of 14.9 - 1.3 kcal/mole. Combining the kinetic data with relative defect concentration data yielded an activation energy for oxygen self-diffusion of 57 - 16 kcal/mole. The enthalpy of formation of doubly ionized oxygen vacancies was calculated to be 126 - 13 kcal/mol. © 1975, The Electrochemical Society, Inc. All rights reserved.

Electrochemical Reduction Of Molybdenum(Vi) Compounds In Molten Lithium Chloride-Potassium Chloride Eutectic, Branko N. Popov, H. A. Laitinen

Faculty Publications

Molybdenum (VI) oxide reacts with molten LiCl-KCl eutectic at 450° to form MoO₂CI₂, which probably is present as an anion MoO₂Cl₄⁼, and pyromolybdate, Mo₂O₇⁼. Both of these species are electrochemically reduced to MoO₂, which can be reoxidized to MoO₂Cl₂ by current reversal. A second reduction step, observed whether MoO₃ or Mo₂O₇²⁻ is added to the melt, can be attributed to the reduction of MoO₄⁻⁻, formed as a secondary reaction product in the first …

An Oxidation Of Para-Nitrotoluene, Albert Edward Meisinger

Theses

The original purpose of this paper was to investigate the reaction kinetics of the air oxidation of para-nitro-toluene (PNT) to para-nitrobenzoic acid (PNBA). The reaction was to be carried out at atmospheric pressure and at temperatures between 100 and 175° C, and in the presence of an oxidation catalyst. However the main problem became one of trying to find a catalyst that would work at these conditions. The catalysts used were nickel acetate, cobaltous acetate, manganous acetate and manganese naphthenate. Hydrogen peroxide was tried as an accelerator for the reaction. None of these worked since no yield greater than 0.01% …

Ferromagnetism In Some Alloys Of The Copper-Manganese-Tin System, Leonard W. Boyd Jr.

Bachelors Theses and Reports, 1928 - 1970

The specific purpose of this investigation is to study the effects of heat treating at various temperatures for different lengths of time, with special attention paid to changes in magnetization. Identical heat-treating conditions were used on several different alloys, the compositions of which are such that some specimens are in the single-phase beta prime and beta regions, whereas others are in two-phase regions. For this investigation, only magnetic measurements will be attempted.

Geology Of A Portion Of The Hand Mine, Argenta Mining District, Beaverhead County, Montana, John Thomas Richards

Bachelors Theses and Reports, 1928 - 1970

The Hand Mine is located in the Argenta Mining District near the town of Argenta. The area surrounding the Hand Mine is characterized by intense thrusting, folding, and igneous activity. The area mapped by the author is in the southeast portion of the mine and differs from the rest of the mine in that no commercial ore has been found. The writer concludes that the steep faulting and flatlying bodies are of two different ages, and that intense oxidation has altered the ore minerals to plumbojarosite.

The Effect Of The Cu:Fe''' Ratio Upon The Current Efficiency In The Electrolysis Of A Copper Sulfate Solution Containing Iron Sulfate, Joseph Thomas Roy, Francis Carroll Moran

Bachelors Theses and Reports, 1928 - 1970

It is a well-known fact that, in the electrolysis of a CuSO₄ solution containing iron sulfate, using insoluble anodes, with the depletion of copper, the point is finally reached where the current efficiency becomes zero. This decrease in current efficiency is due to the oxidation of the ferrous sulfate to the ferric condition at the anode, by the oxygen liberated. The resulting ferric sulfate diffuses over to the cathode and there dissolves copper from the cathode according to the chemical equation Cu + Fe₂ (SO₄)₃ = CuSO₄ + 2FeSO_4. This copper, which has …