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Corrosion Of Steel By Lead Bismuth Eutectic: Year 1 Annual Report, John Farley

Transmutation Sciences Materials (TRP)

The goal is to investigate the corrosion of stainless steel by lead-bismuth eutectic (LBE), which has been proposed for use as a blanket coolant and a spallation target in the transmuter.

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole, Zhiyong Wang, David W. Hatchett

Transmutation Sciences Materials (TRP)

Spallation-neutron-sources, such as those under investigation for use in accelerator-driven transmutation systems, generate neutrons through the collision of high-energy protons, or charged hydrogen atoms, with heavy metal targets such as lead. As a result, these systems also tend to deposit a significant amount of hydrogen in the materials of the transmuter target and superstructure. This can result in accelerated corrosion and changes in the properties of the exposed materials. Of particular importance is a phenomenon called hydrogen embrittlement, in which materials lose their ductility (ability to deform under stress) and become brittle (more susceptible to fracture) after reacting with hydrogen. …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Task V 4th Quarterly Report, Samir Moujaes

Transmutation Sciences Materials (TRP)

The project is moving on target with the newly realigned objective set for the Phase I. Through close communications with Dr. Li and Dr. Jinsuo Zhang from LANL a realignment of the simulation work has been recommended. The reason for that is the vendor of STAR-CD/CHEMKIN had not perfected yet the final coupling of the post processing of output for any potential surface chemistry reaction taking place on the inside pipe surface of the LBE loop. This is because the coupling of CHEMKIN and STAR-CD has been done fairly recently.

Our final effort has been to generate using an innovative …

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

Transmutation Sciences Materials (TRP)

Many of the international efforts to develop transmutation technology, including the U.S., Russian, and European scientific communities, have determined that lead bismuth eutectic (LBE) is a potential material for use as a both a spallation target and a coolant. To exploit this potential, a more thorough understanding of the effect and rates of corrosion on steels, particularly non-Russian alloys, inside the LBE systems is required. Properly controlling the oxygen content in LBE systems has been observed to drastically reduce the corrosion of structural steels in LBE. However, the transport of oxygen and formation of corrosion products is not well understood; …

Nuclear Criticality, Shielding, And Thermal Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth, Denis Beller

Separations Campaign (TRP)

The remediation of nuclear waste created by conventional fission reactors will rely upon the separation of the waste products for further treatment. The UREX+ process now under review will involve the use of an aqueous chemical process to separate out depleted uranium resulting in a product containing minor actinides, fission products, cesium, strontium, technetium, and iodine. The radioactive decay of strontium and cesium produces roughly half of the thermal and gamma production in spent fuel and the relatively short halflife of isotopes of both of these elements requires storage for about 300 years before heat and radiation decreases to safe …

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

Separations Campaign (TRP)

The separation and partitioning of used commercial reactor fuel is a vital component of any reprocessing or transmutation strategy. To process the high actinide fuels required for a transmutation effort, the Chemical Technology Division (CMT) at Argonne National Laboratory (ANL) is developing a pyrochemical separations process. Currently, this work is being done via small experiments. While this is more than sufficient to develop the technologies required to process actinide-bearing fuels, it does not allow for the direct investigation of criticality concerns that would be present in larger systems. As the volume of waste to be treated increases, a higher probability …

Combinatorial Chemistry: A Guide For Librarians, Philip Barnett

Publications and Research

No abstract provided.

Glycine Transport Through A Charged Polysulfone Cation Exchange Membrane, Nuri̇ Ünlü, Hüseyi̇n Kara, Mustafa Ersöz

Turkish Journal of Chemistry

The transport of glycine through a charged polysulfone cation exchange membrane was studied as a function of pH at different initial conditions of less than pH 5.9 and the glycine permeability was explained under the experimental conditions as pH dependent interfacial transport. The glycine permeability increases with a decreasing pH in the receiver phase. The largest permeability was obtained if the initial pH on the source side was pH 5.9 and that on the opposite side was pH 2.0. The transport phenomena can be explained by the interfacial transport based on the interfacial chemical reaction (protonation, deprotonation or ion-exchange) between …

The Effects Of Benzoic Acid In Chloride Solutions On The Corrosion Of Iron And Aluminum, Si̇bel Zor

Turkish Journal of Chemistry

In this work, the corrosion behavior of iron and aluminum was investigated in 0.1 M NaCl solutions with an initial pH value of 8 and containing various concentrations (0, 30, 150, 300 ppm) of benzoic acid. For this purpose, the anodic and cathodic semilogarithmic current-potential curves, weight loss and pH of the solution were determined over time. The changes in the concentrations of benzoic acid in the solutions with time were determined by a UV spectrophotometer. According to the results obtained in this investigation, benzoic acid in 0.1 M NaCl acts on iron and aluminum as an inhibitor. This effect …

Production Of Mesophase Pitch From Coal Tar And Petroleum Pitches Using Supercritical Fluid Extraction, Mustafa Zafer Özel, Keith D. Bartle

Turkish Journal of Chemistry

Supercritical fluid extraction (SFE) is currently being investigated as a possible technique in the production of high quality mesophase pitch from coal tar and petroleum pitches. Mesophase pitch is used to make high technology products, such as carbon fibre. The conventional production of mesophase pitch initially involves the removal of low molecular weight species from coal tar and petroleum pitches. The remaining residue is then transformed into a mesophase pitch through a polymerisation process. The aim of this study involves the extraction of light molecular weight species using SFE. Both petroleum and coal tar pitch contain complex aromatic molecules with …

Determination Of Oxygen And Nitrogen Impurities In Magnesium Metal By Vacuum Distillation And Icp-Oes Techniques, Javed Akhtar, S. K. Durrani, N. A. Chughtai, M. Munir, Bashir Mohammad

Turkish Journal of Chemistry

Due to the various promising properties of magnesium as a structural material and certain other applications such as a reducing agent for refractory metals, magnesium metal has great commercial importance in many technical industries but the presence of oxygen and nitrogen impurities adversely affects its physico-chemical and mechanical properties. Therefore, the exact measurement of oxygen and nitrogen impurities is essential. The accuracy of analytical values of micro amounts of nitrogen and oxygen (\mu g.g^{-1} level) in magnesium metal has been measured indirectly. The conditions for the vacuum distillation (VD) method were optimized. Analysis of residue for magnesium content was studied …

Corrosion Of Reinforcing Steel In Concrete Immersed In Chloride Solution And The Effects Of Detergent Additions On Diffusion And Concrete Porosity, Hülya Kahyaoğlu, Mehmet Erbi̇l, Bi̇rgül Yazici, Ayşe Bahar Yilmaz

Turkish Journal of Chemistry

In order to investigate the corrosion of reinforcing steel in concrete and the effects of chloride ions, oxygen diffusion and detergent additives of linear alkylbenzene (LAB) and linear alkylbenzene sulfonate (LAS), potentiokinetic experiments were carried out. Thus, by embedding steel electrodes into concrete specimens with a water/cement (W/C) ratio of 0.45, current-potential curves were obtained and the compressive strength of the specimens was measured. The electrochemical approach can be used to identify the effect of chloride on steel corrosion in concrete. It was found that the diffusion of chloride and oxygen through concrete and the reduction of oxygen on the …

Biological Reduction Of Perchlorate In Ion Exchange Regenerant Solutions Containing High Salinity And Ammonium Levels, Tina M. Gingras, Jacimaria R. Batista

Civil and Environmental Engineering and Construction Faculty Research

The most promising technologies to remove perchlorate from water are ion exchange and biological reduction. Although successful, ion exchange only separates perchlorate from water; it does not eliminate it from the environment. The waste streams from these systems contain the caustic or saline regenerant solutions used in the process as well as high levels of perchlorate. Biological reduction could be used to treat the regenerant waste solutions from the ion exchange process. A treatment scheme, combining ion exchange and biodegradation, is proposed to completely remove perchlorate from the environment. Perchlorate-laden resins generate brines containing salt concentrations up to 6% or …

Effect Of Tio₂-Mediated Photocatalytic Degradation On The Toxicity Of Orange Ii, Arnaud Eric Nicolas Goutard

Dissertations and Theses @ UNI

C.I. Acid Orange 7 (15510) is the sodium salt of p-[(2-hydroxy-1-naphtalenyl)azo] benzenesulfonic acid. This azo dye is commonly known as Orange II and has been used to dye soaps, shoes, wood and paper (Ramchandani et al., 1994). In the United States and Europe, this dye is not allowed in foodstuffs. The purpose of this study is to investigate the efficiency of a TiO2-mediated photocatalytic oxidation process to degrade Orange II and to determine if Orange II is cytotoxic to certain types of cells. The role of UV radiation and TiO2 particles were examined, as well as the importance of oxygen …

Modification Of Surface Properties Of Polymeric Materials, Rajesh Sharma, Robert A. Sims, Malay K. Mazumder

Journal of the Arkansas Academy of Science

Polymeric materials are successfully used in virtually all industries ranging from semiconductors, and coatings, to household appliances, automotive, and biomedical implants. Polymers generally have excellent bulk physical and chemical properties. However, certain properties of polymers such as low surface energy, low wettability, and high electrical resistivity sometimes limit their applications. Changing the bulk formulation of the polymers can alter some of these properties, but in general this is not acceptable as it can affect "desirable" bulk properties. Surface modification techniques have been used to alter polymer surfaces without affecting the bulk properties of the material. Most polymers have very high …

Compostability Of Degradable Plastics And Its Use In Solid Waste Disposal / Putri Nadzrul Faizura Bt Megat Khamaruddin., Putri Nadzrul Faizura Megat Khamaruddin

Student Works (2000-2009)

Plastic waste generation and quantity generated is a growing concern in many countries including Malaysia. Plastic waste contributes the third highest waste volume in Malaysian municipal solid waste (MSW) next to putrescible waste and paper. ln the year 2000, plastic waste in MSW of Kuala Lumpur was 24.4% by weight from the MSW and most of the plastic waste was dumped into landfills. Landfills in Malaysia are reducing in its useful life as the amount of waste generated is growing every year by 2% and they have become an undesirable option of getting rid of plastic waste because of the …

The Synthesis Of Bromoethoxy And Vinylbenzyloxy Substituted Nlo Chromophores, Michael Joseph Matuszewski

Browse all Theses and Dissertations

Multiphoton-absorption processes have recently attracted growing interest because of the potential impact on a wide spectrum of applications, ranging from data storage to photodynamic therapy. From the materials standpoint, particular interest is centered in designing chromophores that exhibit a large two-photon cross-section. The current research is focused on establishing synthetic routes that lead to the formation of derivatives of N,N-diphenyl-(7-benzothiazol-2-yl)-9,9-diethyl-9H-fluoren-2-ylamine which contain meta functionalization. A bromoethoxy functionalized chromophore, N-phenyl-N-(3-(2-bromoethoxy)phenyl)-7-(benzothiazol-2-yl)-9,9-diethyl-9H-fluoren- 2-ylamine , was synthesized and used as a polymer pendent while a vinylbenzyloxy chromophore, N-phenyl-N-(3-(4-vinylbenzyloxy)phenyl)-7- (benzothiazol-2-yl)-9,9-diethyl-9H-fluoren-2-ylamine, was synthesized as a hydrosilation substrate. A compound containing three chromophores, 1,3,5-tris(3-(N-phenyl- 4-(7-(benzothiazol-2-yl)-9,9-diethyl-9H-fluoren-2- ylanilino)phenoxymethyl)benzene, has …

Purification Of The Hmg1 Protein And Investigation Of Its Interactions With Diepoxide Cross-Linked Dna, Gayle Pageau

Honors Theses

HMG1 is a nonhistone chromosomal protein that binds preferentially to some types of globally modified DNA. HMG1 has been implicated in the cellular response to the anti-cancer agent cisplatin, functioning to block excision repair of specific distorted platinated DNA lesions and resulting in enhanced cytotoxicity. We have investigated whether other DNA-binding agents also produce lesions that are recognized by HMG1. Specifically, we used polyacrylamide gel shift assays to monitor the potential HMG1 binding of diepoxybutane interstrand cross-links, which have been suggested to induce DNA bending. We isolated the native protein from chicken erythrocytes and expressed engineered HMG domain proteins in …

Preparation Of Pvc- Clay Nanocomposites By Solution Blending, Dongyan Wang, Charles A. Wilkie

Chemistry Faculty Research and Publications

PVC-clay nanocomposites have been prepared by solution blending of the polymer with both sodium montmorillonite and an organically modified clay. The nanocomposites have been characterized by X-ray diffraction and transmission electron microscopy; in all cases the materials are best described as mixed immiscible—intercalated nanocomposites, Thermogravimetric analysis shows that, in some cases, the onset temperature of the degradation is enhanced, and the fraction of nonvolatile residue is always decreased. This decrease in the amount of char indicates a significant change in the degradation pathway of the polymer, caused by the presence of the clay. For some preparations, the tensile strength and …

An Xps Study Of The Thermal Degradation Of Polystyrene-Clay Nanocomposites, Jianqi Wang, Jianxin Du, Jin Zhu, Charles A. Wilkie

Chemistry Faculty Research and Publications

X-ray photoelectron spectroscopy, XPS, has been used to examine several polystyrene-clay nanocomposites. The accumulation of oxygen, from the almuniosilicate, on the surface of the polymer was observed, along with the loss of carbon. This confirms that the barrier properties of the clay provide a mechanism by which nanocomposite formation can enhance the fire retardancy of the polymers. No difference is detected depending upon the extent of exfoliation or intercalation of the nanocomposite. #2002 Elsevier Science Ltd. All rights reserved.

Three-Dimensional Structure Of The Complexin/Snare Complex, Xiaocheng Chen, Diana R. Tomchick, Evgenii L. Kovrigin, Demet Araç, Mischa Machius, Thomas C. Südhof, Josep Rizo

Chemistry Faculty Research and Publications

During neurotransmitter release, the neuronal SNARE proteins synaptobrevin/VAMP, syntaxin, and SNAP-25 form a four-helix bundle, the SNARE complex, that pulls the synaptic vesicle and plasma membranes together possibly causing membrane fusion. Complexin binds tightly to the SNARE complex and is essential for efficient Ca²⁺-evoked neurotransmitter release. A combined X-ray and TROSY-based NMR study now reveals the atomic structure of the complexin/SNARE complex. Complexin binds in an antiparallel α-helical conformation to the groove between the synaptobrevin and syntaxin helices. This interaction stabilizes the interface between these two helices, which bears the repulsive forces between the apposed membranes. These results …

Overexpression And Divalent Metal Binding Properties Of The Methionyl Aminopeptidase From Pyrococcus Furiosus, Lu Meng, Shane Ruebush, Ventris M. D'Souza, Alicja J. Copik, Susumu Tsunasawa, Richard C. Holz

Chemistry Faculty Research and Publications

The gene encoding for the methionyl aminopeptidase from the hyperthermophilic archaeon Pyrococcus furiosus (PfMetAP-II; EC 3.4.11.18) has been inserted into a pET 27b(+) vector and overexpressed in Escherichia coli. The new expression system resulted in a 5-fold increase in purified enzyme obtained from a 5 L fermentor growth. The as-purified PfMetAP-II enzyme, to which no exogenous metal ions or EDTA was added, was found to have 1.2 equiv of zinc and 0.1 equiv of iron present by ICP-AES analysis. This enzyme had a specific activity of 5 units/mg, a 60-fold decrease from the fully loaded Fe(II) …

A Comparison Of Various Methods For The Preparation Of Polystyrene And Poly(Methyl Methacrylate) Nanocomposites, Dongyan Wang, Jin Zhu, Qiang Yao, Charles A. Wilkie

Chemistry Faculty Research and Publications

Polymer−clay nanocomposites of styrene and methyl methacrylate have been prepared by bulk, solution, suspension, and emulsion polymerization as well as by melt blending. Two different organic modifications of montmorillonite have been used:  one contains a styryl monomer on the ammonium ion while the other has no double bond. The organic modification as well as the mode of preparation determines if the material will be exfoliated or intercalated. Exfoliation is more likely to occur if the ammonium ion contains a double bond which can participate in the polymerization reaction, but the mere presence of this double bond is not sufficient to …

An Xps Investigation Of Thermal Degradation And Charring Of Pmma Clay Nanocomposites, Jianxin Du, Jin Zhu, Charles A. Wilkie, Jiangqi Wang

Chemistry Faculty Research and Publications

Poly(methyl methacrylate)–clay nanocomposites have been studied using X-ray photoelectron spectroscopy. It is clear that as the polymer undergoes thermal degradation, the clay accumulates at the surface and the barrier properties which result from this clay accumulation have been described as the reason for the decreased heat release rate for nanocomposites. The surface composition of the clay changes as the nanocomposite is heated and the changes are affected by the organic-modification that were applied to the clay in order to prepare the nanocomposite.

Remote Sensing: A New Tool For Automobile Inspection And Maintenance, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

Federally-mandated emissions testing of automobiles in Colorado has decreased emissions, albeit much less than predicted. Recent breakthroughs in manufacturing low emitting vehicles and in remote sensing of a moving car’s exhaust could enable Colorado to phase out or drastically increase the efficiency of treadmill-style testing centers. Remote sensing technology now allows a piece of equipment small enough to fit in a van to assess the mass of pollutants per gallon of fuel emitted by a passing car. Once an emissions scofflaw is identified, a number of options exist:

· immediate pullover and ticketing by a police officer;

· a “smart …

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 3, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Effect Of Oxygen Vacancies On The Magnetic Structure Of The La₀.₆Sr₀.₄Feo3-Δ Perovskite: A Neutron Diffraction Study, Zili Chu, William B. Yelon, Jinbo Yang, William Joseph James, Harlan U. Anderson, Yixiang Xie, Satish K. Malik

Physics Faculty Research & Creative Works

Magnetic interactions in perovskite compounds of the type La_1-xSr_xMO_3-δ (M=3d transition such as Mn and Fe) are presumed to arise through a super exchange between 3d electrons of the magnetic ions via oxygen orbitals. The magnetic structure of La_0.6Sr_0.4FeO_3-δ has been studied with neutron diffraction. Oxygen vacancies were created by annealing samples under various gases including N₂, air and mixtures of CO/CO₂. All La_0.6Sr_0.4FeO_3-δ compounds maintain the rhombohedral structure (space group R3̄c). The air- or oxygen-annealed samples have almost no oxygen …

Electrical And Magnetotransport Properties Of Canted Antiferromagnet Dy₅Si₂Ge₂, R. Nirmala, V. Sankaranarayanan, K. Sethupathi, Zili Chu, William B. Yelon, V. Prasad, A. V. Morozkin, Satish K. Malik, S. V. Subramanyam

Physics Faculty Research & Creative Works

Summary form only given. Since the giant magnetocaloric effect is encountered in a ferromagnetic Gd5Si2Ge2 alloy near room temperature it is considered as a suitable material for magnetic refrigerator applications. Also a commensurate structural transition occurs at the magnetic transition temperature and there is a good correlation between the crystal structure and magnetic properties. Such observations have triggered numerous experimental studies on similar rare earth alloys and compounds. We have synthesized its Dy- analogue, namely, Dy5Si2Ge2 and have characterized it by means of room temperature X-ray diffraction, ac magnetic susceptibility (15 K - 300 K), electrical resistivity (at zero field …

Motion Based Event Recognition Using Hmm, Gu Xu, Yu-Fei Ma, Hong-Jiang Zhang, Shiqiang Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Motion is an important cue for video understanding and is widely used in many semantic video analyses. We present a new motion representation scheme in which motion in a video is represented by the responses of frames to a set of motion filters. Each of these filters is designed to be most responsive to a type of dominant motion. Then we employ hidden Markov models (HMMs) to characterize the motion patterns based on these features and thus classify basketball video into 16 events. The evaluation by human satisfaction rate to classification result is 75%, demonstrating effectiveness of the proposed approach …

Adsorptive Immobilization Of Cytochrome C On Indium/Tin Oxide (Ito): Electrochemical Evidence For Electron Transfer-Induced Conformational Changes, Asma El Kasmi, Michael C. Leopold, Ryan Galligan, Rebecca T. Robertson, S. Scott Saavedra, Kacem El Kacemi, Edmond F. Bowden

Chemistry Faculty Publications

The adsorptive immobilization and electrochemistry of horse and yeast cytochrome c on indium/tin oxide (ITO) electrodes is reported. Near-monolayer coverage was achieved in pH 7 phosphate buffers of ionic strength equal to 10 and 50 mM, respectively, for the horse and yeast species. The layers exhibit very well-behaved voltammetry and are stable on the timescale of hours to days. Cyclic voltammetry revealed quasireversible behavior that is a product of both electron transfer (ET) kinetics and ET-induced conformational changes. A square scheme mechanism linking the redox states and the conformational states is proposed. Using a simple ET kinetic model that adequately …