Physical Sciences and Mathematics Commons^™

Comparison Of Thermal Cyclic Oxidation Of The Pvd Ni-Al And Hvof-Mcraly Coatings, Chang J.T., H. Yeh C., He J.L., Chen K.C.

Journal of Electrochemistry

A PVD process_cathodic arc plasma ion plating was used to deposit Ni_Al films on Inconel 600 superalloy. The oxidation behaviors of PVD Ni_Al coating and the thermal sprayed CoCrAlY coatings were revealed and compared by performing cyclic thermal oxidation test at 1 100 ℃ to evaluate its feasibility. Experimental results showed that the films with different compositions of Ni 62 Al 38 , Ni 63 Al 37 and Ni 69 Al 31 could be obtained when using Ni 52 Al 48 , Ni 60 Al 40 and Ni 70 Al 30 as targets, respectively. During the cyclic thermal oxidation test, …

Fabrication Of Scanning Micro Cl~- Probe And In Situ Imaging Of Cl~- At The Interface Of 2024 Al Aloy/Solution, Yu-Hua Lin, Min-Hua Shao, Rong-Gang Hu, Yan Li, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

Micro combination Ag/AgCl electrode with a tip measuring tens micron in diameter was fabricated. The probe satisfied in situ imaging of Cl - distribution at metal surface in chloride solution because of its excellent linearity between potential and Cl - concentration, rapid response, good stability and selectivity. With the aid of the home made Micro Electrode Scanning system and scanning Cl - probe, the effect of the [Cl - ] at 2024_Al/solution interface on localized corrosion process was investigated. It was demonstated directly that Cl - ion in solution immigrated toward, then adsorbed preferentially and accumulated at the junction between …

Synthesis Of Polyunit Vapor Phase Inhibitor And Its Volatile Corrosion Inhibition Performance, Da-Quan Zhang, Li-Xin Gao, Guo-Ding Zhou

Journal of Electrochemistry

A Mannich Base derivative (BMMCH), containing two morpholinum moieties and one cyclohexylamnonium moiety, was synthesized through aminomethy1 reaction. Its configuration was verified by IR and 1H_NMR. Its volatile rustproofing effect was appraised by volatile rustproofing sieve test and vapor inhabitability test. The result shows that BMMCH has good protection effect for carbon steel. BMMCH has lower volatility compared with dicyclohexylamnonium nitrite (DICHAN) via closed space volatile weight_loss test. The inhibition mechanism was studied by potentiodynamic polarization electrochemistry technique in ASTM simulated atmospheric water. The corrosion potential of carbon steel electrode shifted to a negative direction when BMMCH was joined in. …

Effect Of Heat Laminating Aggregation Status Of Polymer Lithium-Ion Battery Cathode On Battery Performance, Ming-Gang Jin, Quan-Feng Dong, Ming-Sen Zheng, Li Huang, Hui-Qun Cai, Jin-Qua You, Zu-Geng Lin

Journal of Electrochemistry

Multi_layer heat laminated polymer lithium ion battery was made, the effect of temperature of cathode laminating on battry performance was also investigated. It was discovered that suitable temperature of cathode laminating is critical to battery performance and is a key parameter to manufacture process control of polymer lithium ion battery.

Electrochemistry And Electrocatalysis Of A Novel Μ-Oxamido Copper(Ⅱ) Binuclear Complex, Gui-Lian Gao, Guo-Bao Li, Qiu-Xia Yang, Xue-Lin Wang

Journal of Electrochemistry

In this paper,the cyclic voltammetric and spectroelectrochemical behaviors of μ _oxamido Copper(Ⅱ) Binuclear Complex (deCu) in PBS were studied.Cyclic voltammograms of this complex in PBS(pH=9)exhibited two reductive peaks( E pc1 =-0.25 V, E pc2 =-0.50 V)at hanging mercury drop electrode(HMDE),peaks at -0.50 V and -0.25 V corresponded to the reduction of ligand and copper(Ⅱ)_complex, respectively.The spectroelectrochimical experiments showed that there was a new absorption band at 440 nm,and the absorption peaks at 270 nm,280 nm red shifted to 300 nm,310 nm under potential of -0.75 V.It was meant that the Cu(Ⅱ) turned into low valent copper,simultaneously,a new large coupling system …

The Second Circular For 12th National Conference On Electrochemistry Of China

Journal of Electrochemistry

No abstract provided.

Influence Of Marine Organisms Upon Corrosion Of Steel Piling Systems, Jiunn-Shyong Luo, Cliff Cliff, Rau Rau, Kuei-Ching Chen

Journal of Electrochemistry

To study the influence of marine organisms upon corrosion of ASTM A36 steel piling sysems,specimens were immersed in both natural and synthetic seawater.Electrochemical techniques such as linear polarization resistance and electrochemical impedance scan(EIS) were applied to evaluate corrosion of the steel.The results indicated that attachment of marine organisms to form fouling layers on the steel surface reduced general corrosion,but localized corrosion occurred underneath marine organisms.An equivalent circuit model was established to simulate attachment of marine organisms upon carbon carbon steel surfaces.

Electrochemical Response Of Deformed Marine Steel In Sea-Mud Containing Sulfate Reducing Bacteria, Yan-Liang Huang

Journal of Electrochemistry

The corrosion failure behavior of marine steel is affected by stress,which exists in offshore structures at sea_mud region.In order to conduct the study of stress on the electrochemical response of a selected steel,a kind of natural sea_mud containing sulfate reducing bacteria(SRB) was collected.The electrochemical response of cyclic stress of the specimen with and without cracks in sea_mud was analyzed.

Study On Adsorption Behavior Of Inhibitors On N80 Steel, Ai-Kui Li, Guo-Min Li, Xing-Peng Guo

Journal of Electrochemistry

The de_adsorption behavior of four inhibitors on N80 steel with and without carbonate film was investigated by polarization and electrochemical impedance spectroscopy (EIS) techniques. It was found that,for different inhibitors,de_adsorption behavior and adsorbability between with and without carbonate film are different.Furthermore,acidic inhibitor and small size molecule inhibitor shows different inhibition behavior.

Discussion On Factors Of Unstable 304 Stainless Steel Stress Corrosion Cracking, Xin-Sheng Zhang, Chun-Chun Xu, Gang Hu

Journal of Electrochemistry

The 304 stainless steels were stretched at low temperatures to get different martensite phase transformation.Ferrmagnetometer was used to measure the martensite phase content. It was found that the dislocation density of 304 stainless sted was increased unavoidably with increase of deformation.Transmission electron microscope (TEM) was used to study the distribution of the dislocation.The influence of microstructure change on SCC of 304 stainless steel was discussed by slow strain rate testing (SSRT) in 42% MgCl 2 boiling solution,metallurgical microscope and scanning electron microscope (SEM).The results showed that martensite phase and dislocation flaw act together on the SCC susceptibility of 304 stainless …

The Electroless Plating Ni-Fe-P Alloy And Its Voltammetric Behavior, Sen-Lin Wang, Hui-Huang Wu

Journal of Electrochemistry

Electroless Ni_Fe_P alloy deposition from an alkaline bath, containing sodium hypophosphite as reducer, boric acid as buffer agent and sodium citrate as complexing agent, was investigated. To increase the plating rate and to inprove the bath stability, the deposition parameters were optimized. The effects of process parameters (pH,temperature and mole ratio of [Fe 2+ ]/([Ni 2+ ]+[Fe 2+ ]) on the plating rate and deposit composition were examined and it was found that the presence of ferrous sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the per_centage of iron in the electroless Ni_Fe_P …

The Mechanism Of Electrocatalytic Reduction Of Oxygen On Manganese Dioxide, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai, Li-Fen Xiao

Journal of Electrochemistry

The oxygen electroreduction on the MnO 2 electrode was investigated by analysis of the polarzation properties of oxygen reduciton and its dependence on MnO 2 discharge state,in combination with the characterization of discharge intermediate and the kinetic parameters of the oxygen reduction.Based on the experimental observation and mechanistic analysis,it was suggested that the reduction of oxygen was closely related to the discharge behaviors of MnO 2 .When MnO 2 was electrochimically reduced to MnOOH,it was immediately oxidized by oxygen molecules. Thus the oxygen reduction proceeds through continuous oxidation of the discharge product of MnO 2 and the MnO 2 catalyst …

Study On The Electrochemical Behavior Of Methy1 Green And Methy1 Green-Cyclodextrin Supramolecule System, Yu-Jing Guo, Jing-Hao Pan, Chun-Hua Guo, Hong-Lian Zheng

Journal of Electrochemistry

Electrochemical behavior of methyl green in different kinds of solution and the supramolecule system of methyl green_cyclodextrin were studied.Inclusion constants of four cyclodextrin with emthyl green were determined by “electric current method”.The order of inclusion ability is HP_β_CD,β_CD,SBE_β_CD and CM_β_CD.The molar ratio of inclusion complexes of methyl green with CDs is 1:2. A possible mechanism was reported for methyl green.

Study Of Electrolyzed Pure Iron And Rrr_H Method, Wei_Min Cao, Ren-He Yin, Hui-Gen Yan, Yi-Bing Zhang, Ying-Chun Dai

Journal of Electrochemistry

The high purity electrolytic iron was made from scrap iron chips. The purity of electrolyzed pure iron was above 99.98% by chemical analysis. The resistivity was measured at 298 K and at 4.2 K under an applied longitudinal_magnetic field of 800 0 e. The ratio of resistivity at 298 K to that at 4.2 K, The value of residual resistivity ratio (RRR H) roughly depended on the purity of iron. Pure iron electrolyzed on Ti substrate had very compact texture as evident by SEM.

Why Should Students Do Research?, Bruce R. Branchini

Convocation Addresses

No abstract provided.

Phase Changes In Internally Mixed Maleic Acid/Ammonium Sulfate Aerosols, Sarah D. Brooks, Rebecca M. Garland, Matthew E. Wise, Anthony J. Prenni, Melinda Cushing, Erika Hewitt, Margaret A. Tolbert

CUP Faculty Research

A temperature controlled flow tube system equipped with Fourier transform infrared (FTIR) detection of particle phase and relative humidity was used to measure the deliquescence and efflorescence of ammonium sulfate, maleic acid, and internally mixed maleic acid/ammonium sulfate particles. Our results indicate that maleic acid aerosols begin to take up water starting at a low relative humidity, ∼20%, and continue the constant uptake of water until the final deliquescence relative humidity (DRH), 89%, is reached. Internally mixed particles containing maleic acid and ammonium sulfate were found to deliquesce at a lower relative humidity (RH) than either of the pure species. …

Development Of A Systems Engineering Model Of The Chemical Separations Process: Quarterly Progress Report 5/16/03- 8/15/03, Yitung Chen, Randy Clarksean, Darrell Pepper

Separations Campaign (TRP)

Two activities are proposed in this Phase I task: the development of a systems engineering model and the refinement of the Argonne code AMUSE (Argonne Model for Universal Solvent Extraction). The detailed systems engineering model is the start of an integrated approach to the analysis of the materials separations associated with the AAA Program. A second portion of the project is to streamline and improve an integral part of the overall systems model, which is the software package AMUSE. AMUSE analyzes the UREX process and other related solvent extraction processes and defines many of the process streams that are integral …

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Sean Hsieh, Randy Clarksean, Darrell Pepper

Separations Campaign (TRP)

The AFCI program is developing technology for the transmutation of nuclear waste to address many of the long-term disposal issues. An integral part of this program is the proposed chemical separations scheme.

Nearly all issues related to risks to future generations arising from long-term disposal of such spent nuclear fuel is attributable to about 2% of its content. Such 2% is made up primarily of plutonium, neptunium, americium, and curium (the transuranic elements) and long-lived isotopes of iodine and technetium created as products from the fission process in power reactors. When transuranics are removed from discharged fuel destined for disposal, …

Synthesis Of Chiral Surfactants For Enantioselective Organic Synthesis., Kalyan Mondal

Electronic Theses and Dissertations

The first step of the synthesis of the hydrocarbon-based chiral surfactant (2) involved the methylation of (S)-leucinol to give (2S)-N-hexadecyl-N,N-dimethyl-(1-hydroxy-4-methyl-1-pentyl)-2-ammonium bromide (2.92g, 67%). The chiral surfactant was synthesized by reacting (2S)-N,N-dimethyl-2-amino-4-methyl-1-pentanol (1) with bromohexadecane (2.06g, 71%). The functionalized styrene for the polymer supported chiral catalyst (6) was synthesized by reacting (1) with 4-vinylbenzyl chloride. The polymerization was carried out with 10% of the functionalized monomer (5) (1.26g, 70.2%), 5% cross-linking agent divinylbenzene, and 85% of styrene with AIBN as the initiator. The structure of each of the products was confirmed by using FTIR and NMR spectroscopy. The activity of the …

Spectroscopic Examination Of The Catalytic Decomposition Of Hydrogen Peroxide By A Copper (Ii) Complex Of A Dissymmetric Schiff Base And An Imidazole Derivative., John D. Davis Jr.

Electronic Theses and Dissertations

Previous studies involving copper (II) complexed with a dissymmetric Schiff base and imidazole derivatives had identified catalase activity of these complexes towards H₂O₂. Reactions such as this are of great interest due to the important role of copper-based complexes in biological systems. Our research has been conducted to add to the base of knowledge regarding the efforts of other researchers to investigate copper complexes that exhibit similar reactivity as copper-based proteins towards dioxygen. The copper complex chosen for this study contained a tri-dentate Schiff base adduct which, when complexed with an imidazole derivative, limited the manner …

Growth, Conductivity, And Vapor Response Properties Of Metal Ion-Carboxylate Linked Nanoparticle Films, Michael C. Leopold, Robert L. Donkers, Dimitra Georganopoulou, Megan Fisher, Francis P. Zamborini, Royce W. Murray

Chemistry Faculty Publications

Nanoparticles of metals (Au, Ag, Pd, alloys) in the size range 1–3 nm diameter can be stabilized against aggregation of the metal particles by coating the metal surface with a dense monolayer of ligands (thiolates). The stabilization makes it possible to analytically define the nanoparticle composition (for example, Au140(hexanethiolate)53, I) and to elaborate the chemical functionality of the protecting monolayer (for example, Au140(C6)35(MUA)18, II, where C6 = hexanethiolate and MUA = mercaptoundecanoic acid). Network polymer films (IIfilm) on interdigitated array electrodes can be prepared from II, based on cation coordination (i.e., Cu2+, Zn2+, Ag+, methyl viologen) by the …

Strategies For Enhancing The Performance Of Chemical Sensors Based On Microcantilever Sensors, Christopher Tipple

Doctoral Dissertations

Microcantilever (MC) based chemical sensors have become more widely used during the past 10 years due to the advantages they possess over other chemical sensors. One of the most significant characteristics is their extremely high surface to volume ratio. This key facet allows surface forces that can be ignored on a macroscale to become a significant sensing transduction mechanism. MC based sensors also exhibit a higher mass sensitivity to adsorbates than do many other chemical sensor platforms. Under many conditions, MC based sensors directly translate changes in Gibbs free energies due to analyte-surface interactions into mechanical responses. However, the widespread …

“Enhancement Of Sensitivity And Selectivity Of Chemical Sensors Through Thin Film Coatings And Surface Modifications, Joseph Jeremy Headrick

Doctoral Dissertations

Chemical sensors have become major analytical tools for how we monitor
and obtain information about the chemical nature of ourselves and our
surroundings. Two characteristics of chemical sensors that are under constant
development and improvement are their selectivity and their sensitivity.
Selectivity is a concern of any chemical sensor, without it the signal obtained by
a chemical sensor cannot be related to the target species concentration with any
confidence. With chemical sensors the selectivity is generally created by the
used of a chemical recognition layer such as a permeable membrane, or a thin
chemical film. The sensitivity of a chemical …

Dielectric Permittivity And Electric Modulus In Bi2ti4o11, Jianjun Liu, Chun-Gang Duan, Wei-Guo Yin, Wai-Ning Mei, Robert W. Smith, John R. Hardy

Physics Faculty Publications

Frequency and temperature dependences of dielectric permittivity and electric modulus of pure and Ba-doped Bi2Ti4O11 were studied in the ranges of 1021–106 Hz and 2150–350 °C, respectively. We found that the antiferroelectric phase transition temperature of Bi2Ti4O11 decreases with Ba doping. In the permittivity studies, we also observed dielectric relaxation peaks shift to higher temperature with increasing frequency. Furthermore, in the electric modulus formalism, conducting peaks were uncovered above 150 °C in addition to the dielectric relaxation peak. We discussed the mechanisms for the dielectric relaxation and conduction processes based on TiO6 octahedra distortion and a space-charge model.

Effects Of Fiberimatiux Interactions On The Interfacial Deformation Micromechanics Of Cellulose-Fiberipolymer Composites, William Tai-Yin Tze

Electronic Theses and Dissertations

The overall objective of this dissertation was to gain an understanding of the relationship between interfacial chemistry and the micromechanics of the cellulose-fiber/polymer composites. Regenerated cellulose (lyocell) fibers were treated with amine-, phenylamine-, phenyl-, and octadecyl-silanes, and also styrene-maleic anhydride copolymer. Inverse gas chromatography was conducted to evaluate the modified surfaces and to examine the adsorption behavior of ethylbenzene, a model compound for polystyrene, onto the fibers. Micro-composites were formed by depositing micro-droplets of polystyrene onto single fibers. The fiber was subjected to a tensile strain, and Raman spectroscopy was employed to determine the point-to-point variation of the strain- and …

Dramatic Nondipole Effects In Low-Energy Photoionization: Experimental And Theoretical Study Of Xe 5s, Oliver Hemmers, Renaud Guillemin, E. P. Kanter, B. Krassig, Dennis W. Lindle, S. H. Southworth, R. Wehlitz, J. Baker, A. C. Hudson, M. Lotrakul, D. Rolles, Wayne C. Stolte, I. Tran, A. Wolska, S. Yu, M. Ya Amusia, K. T. Cheng, L. V. Chernysheva, W. R. Johnson, S. T. Manson

Environmental Studies Faculty Publications

The Xe 5s nondipole photoelectron parameter γ is obtained experimentally and theoretically from threshold to ∼200  eV photon energy. Significant nondipole effects are seen even in the threshold region of this valence shell photoionization. In addition, contrary to previous understanding, clear evidence of interchannel coupling among quadrupole photoionization channels is found.

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics - Phase Three, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The proposed work will combine chemical kinetics and hydrodynamics in target and test-loop lead-bismuth eutectic (LBE) systems to model system corrosion effects. This approach will result in a predicative tool that can be validated with corrosion test data, used to systematically design tests and interpret the results, and provide guidance for optimization in LBE system designs. The task includes two subtasks. The first subtask is to try to develop the necessary predictive tools to be able to predict the levels of oxygen and corrosion products close to the boundary layer through the use of Computational Fluid Dynamics (CFD) modeling. The …

Synthesis Of Porous Monoclinic Tungsten Oxides And Their Application In Sensors, Anil Bhalchandra Waghe

Electronic Theses and Dissertations

Semiconducting metal oxide sensors are limited in their usage because of their poor detection selectivity. The current approach to achieve better selectivity in SMO detection uses prefiltering/preconcentration schemes to reduce the number of gases in contact with the sensor in combination with array-based detection. In this thesis we have investigated different materials and approaches for use as elements in an array based detection system.

One approach we have investigated involves the use of porous monoclinic WO₃ to obtain size selectivity in detection within the sensing element itself. In chapter 3 we describe the synthetic protocol used to generate high …

Photofragmentation Dynamics Of Core-Excited Water By Anion-Yield Spectroscopy, Wayne C. Stolte, M. M. Sant'anna, Gunnar Ohrwall, Maria Novella Piancastelli, I. Dominguez-Lopez, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

Partial-anion and- cation yields from H₂O are presented for photon energies near the oxygen K edge. The O^- yield exhibits a feature above threshold attributed to doubly excited states, in contrast to the H^- and cation yields, which are nearly featureless above threshold. Additionally, the lack of the OH^- fragment indicates radiative decay and provides a negligible amount of anion formation.

Receptor Activation Regulates Cortical, But Not Vesicular Localization Of Ndp Kinase, Betty C. Gallagher, Kimberly A.P. Mitchell, Gabor Szabo, Angela De S. Otero

Faculty Publications and Presentations

We used immunofluorescence techniques to determine the localization of nucleoside diphosphate (NDP) kinase in NIH-3T3 fibroblasts. We found that cytoplasmic NDP kinase can be separated into two populations according to subcellular localization and response to extracellular stimuli. Specifically, within minutes of stimulation of resting fibroblasts with serum, growth factors or bombesin, a portion of NDP kinase becomes associated with membrane ruffles and lamellipodia. Another pool of NDP kinase accumulates independently of stimulation around intracellular vesicles. Transfection of cells with activated Rac mimics, whereas expression of dominant negative Rac inhibits, the effects of extracellular stimulation on the translocation of NDP kinase …