Physical Sciences and Mathematics Commons^™

Complex Effects Arising In Smoke Plume Simulations Due To Inclusion Of Direct Emissions Of Oxygenated Organic Species From Biomass Combustion, Sherri A. Mason, Richard J. Field, Robert J. Yokelson, Michael A. Kochivar, Mark R. Tinsley, Darold E. Ward, Wei Min Hao

Chemistry and Biochemistry Faculty Publications

Oxygenated volatile organic species (oxygenates), including HCOOH, H₂CO, CH₃OH, HOCH₂CHO (hydroxyacetaldehyde), CH₃COOH, and C₆H₅OH, have recently been identified by Fourier transform infrared measurements as a significant component of the direct emissions from biomass combustion. These oxygenates have not generally been included in the hydrocarbon-based initial emission profiles used in previous photochemical simulations of biomass combustion smoke plumes. We explore the effects of oxygenates on this photochemistry by using an established initial emission hydrocarbon profile and comparing simulation results obtained both with and without addition of the above six …

Jno2 At High Solar Zenith Angles In The Lower Stratosphere, R. S. Gao, L. A. Del Negro, W. H. Swartz, R. J. Salawitch, S. A. Lloyd, M. H. Proffitt, D. W. Fahey, Stephen G. Donnelly Ph.D., J. A. Neuman, R. M. Stimpfle, T. P. Bui

Chemistry Faculty Publications

In situ measurements of NO, NO2, O3, HO2, C1O, pressure, and temperature have been made at high solar zenith angles (SZA, 70° - 93°) in the lower stratosphere. These measurements are used to derive the photolysis rate of NO2, JNO2, using a time-dependent method. The resultant JNO2 values and the results of a multiple-scattering actinic flux model show a linear relationship throughout the SZA range. The difference of the two sets of JNO2 values of about 11% suggests that the model scattering calculation is very accurate at high SZA conditions near sunrise and sunset.

Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka

Faculty Publications

Through the use of variable disulfide crosslinkers, we have created polyacrylamide gels whose shape can be altered after polymerization. N,N'-bisacryloylcystamine is incorporated as a crosslinker, along with a smaller amount of a permanent crosslinker. After polymerization, the disulfide bonds are cleaved into thiols through reduction. By reoxidizing the thiols with the gel held in a new macroscopic shape, a new set of disulfide bonds is formed, and the gel is forced to adopt the new shape. Retension of the new shape improves with greater distortion from the original shape, as well as with increased concentration of variable …

Molecular Dynamics Simulation Of Supersaturated Vapor Nucleation In Slit Pore. Ii. Thermostatted Atomic-Wall Model, K.T. Kholmurodov, K. Yasuoka, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Molecular dynamics simulations of nucleation of a supersaturated Lennard-Jones vapor in slit nanopores are carried out. In this study we extend a previous work [K. Yasuoka, G. T. Gao, and X. C. Zeng, J. Chem. Phys. 112, 4279 (2000)] in that the walls of the slit are treated as actual atomic walls serving as both the confining solid surfaces and a thermostat. The walls are fixed in place in a fcc lattice structure and wall atoms are subjected to a stiff biharmonic potential thereby bounded to lattice sites. The two walls of the slit have an identical surface [fcc (100)], …

Self-Assembled Aggregates Of Neutral Nonlinear Optical Dyes In Smectite Clay Films, Mark Kostuk

Honors Theses

The field of photonics relies on nonlinear optical (NLO) materials and their unique light interacting properties to guide and manipulate light for such uses as optical switches and optical data storage. Hybrid organic-inorganic composites offer excellent routes to such materials synthesis. We report herein the first study of neutral organic NLO chromophores adsorbed onto hectorite and laponite clay films. Seven different dyes (disperse red 1; disperse red 13; disperse red 19; disperse orange 3; disperse orange 13; disperse orange 25, and DANS, [4-dimethylamino-4' -nitrostilbene]), and two exchangeable cations (sodium and zinc), are used to create the hybrid films. The nature …

Separation Of Chiral Controlled Substances Using Capillary Electrophoresis, Tania Magoon

Honors Theses

The separation of the chiral narcotic propoxyphene by capillary electrophoresis (CE) is the goal of this work. A three-way collaboration between our research group, Professor lsiah Warner (LSU) and the New York State Forensic Investigation Center is underway to separate propoxyphene enantiomers and to develop a protocol for the Forensic Center. We are investigating the application of both polymer surfactants and cyclodextrins as CE additives for the separation of enantiomeric propoxyphene. We have synthesized or obtained several polymerized N-undecylenyl-L-amino acid and N-undecylenyl-L-dipeptide derivatives as a pseudo-stationary phase in capillary zone electrophoresis for the separation of chiral compounds. Though no separation …

Interactions Between Oxazine Dyes And Sodium Dodecyl Sulfate Studied By Molecular Spectroscopy, Michael R. Webb

Honors Theses

We present the results of a fundamental investigation of how the presence of surfactant affects the self-interaction of cationic laser dyes in aqueous solution. Oxazine 1 and oxazine 170 are known to form non-fluorescent H-aggregates (n-stacked dimers). The interactions of each of these laser dyes with sodium dodecyl sulfate (SDS), a micelle forming, anionic surfactant, have been examined using UV-visible absorption and fluorescence spectroscopy, fluorescence anisotropy, and Rayleigh scattering. The colors of oxazine 170 solutions are visually distinguishable into three stages: solutions with no SDS, solutions with SDS below the erne (8mM), and solutions with SDS concentrations above the erne. …

Structural And Functional Analysis Of Mutant Matal Homeodomains By Multidimensional Nmr Spectroscopy, David F. Ott

Honors Theses

Homeodomain proteins are transcription factors that contain a conserved 60- residue sequence, beginning with an N-terminal unstructured arm, followed by an alpha helix, a loop, and a helix-tum-helix. The yeast protein MATa1 is unusual among homeodomains in that, as a monomer, it binds very poorly to its DNA operator. However, the a1- α2 heterodimer binds to the hsg operator with 3000 times the affinity it has for nonspecific DNA. Studies have shown that most of the heterodimer's binding specificity is due to a1 rather than α2 (1,2). To identify the structural changes that transform al into a strong, sequence-specific DNA …

Surface Modification Of Diamond And Determination Of Kinetics And Mechanism Of Modification Reactions, Humera Farooq

Masters Theses

A series of photochemically modified diamond surfaces were prepared. Surface functional groups added included, chlorine, bromine, methoxy, amine, methylamine, dimethylarnine and trimethylammonium chloride. Photochemically chlorinated and brominated diamond surfaces were used as synthetic intermediates. The modified diamond surfaces were characterized by Diffuse Reflectance Infrared Spectroscopy (DRIFT) and X-ray Photoelectron Spectroscopy (XPS).

The study was mainly focused on understanding the kinetic processes and reaction mechanism of modified surfaces. The observed rate constants for surface hydrogen loss and HCl (g) evolution were found to be identical. Similar rate constants were observed for amine substitution and consumption of ammonia.

The study of action …

Cross-Linking Of Polystyrene By Friedel-Crafts Chemistry: Reaction Of P-Hydroxymethylbenzyl Chloride With Polystyrene, Hongyang Yao, Michael A. Mckinney, Caroline Dick, John J. Liggat, C.E. Snape, Charles A. Wilkie

Chemistry Faculty Research and Publications

p-Hydroxymethylbenzyl chloride was found to be an effective cross-linking agent for polystyrene. The reaction was found to occur by Friedel–Crafts alkylation between the benzyl alcohol/chloride functional groups in the additive and phenyl ring in polystyrene. The reaction was studied by TGA–IR to monitor the evolution of hydrogen chloride and water, and the structure of the resultant gel was analyzed by solid state NMR and elemental analysis. The potential application in flame-retardancy was evaluated using Cone calorimetry.

Quantification Of Benzo[A]Pyrene-Guanine Adducts In In Vitro And In Vivo Tissue Samples By Lc Tandem Mass Spectrometry, Po-Chang Chiang

Dissertations

No abstract provided.

Live Demonstration Of The Personal Response System: A Tool For Prying Classroom Feedback From Students, Thomas Goyne

Thomas Goyne

No abstract provided.

A Biochemistry Laboratory Course Which Provides A 'Taste Of Research, Thomas Goyne

Thomas Goyne

No abstract provided.

Coating Of Aluminum Powder With Polymers In Supercritical Carbon Dioxide, Li Yuan

Theses

Eleven polymers were used to produce coatings (2-20 nm) on the surface of an aluminum powder to modify its properties. The polymers studied are polyisobutylene (PIB), poly (vinylidene fluoride) (PVF), poly (methyl methacrylate) (PMMA), polystyrene (PS), poly(ethylene terephthalate) (PETP), poly(4-vinylbiphenyl) (PVB), poly(4-vinylpyridine) (PVP), poly(4-bromo styrene) (PBS), poly (vinylidene fluorideco-hexafluoropropylene) (PVFH), poly (styrene-co-methyl methacrylate) (PSMMA), poly (vinyl chloride-co-vinyl acetate) (PVCVA). Supercritical carbon dioxide was used as a solvent and as a transport medium. Coated aluminum powders exhibit enhanced resistance to the dissolution in basic solutions. The protective properties of the polymeric films were quantified based on the dissolution rate. Polymeric films …

The Effect Of Preparation Condition On The Photoelectrochemical Performance Of Both The Pani Film And Tio_2-Pani Composite Film On Au, Huai-Guo Huang, Hong-Ping Zhang, Zhi-Xin Zheng, Yan-Yan Xi, Ling-Ling Wu, Zhong-Hua Lin

Journal of Electrochemistry

Both the PANI(polyaniline) film and TiO 2_PANI composite film on the PATP(p_aminothiophenol)/Au substrate were obtained under different preparation condition by electrochemical methods, and their photoelectrochemical performances were also studied.The results showed that the photoelectrochemical performances of the films depend deeply on the comditions of preparation.The self_assembling of PATP favors the adhesion of PANI.The partially_oxidized PANI has a greater photoelectrochemical response than that of the reduced PANI and oxidized PANI.There is an optimum of film thickness for the photoelectrochemical performance of PANI film.Heat treating is in favor of the photoelectrochemical performance of TiO 2,but decreases the photocurrent response of PANI film.There …

Electrochemical Studies On The Intermetallic Interaction In Binuclear Ruthenium(Ⅱ) Complexes, Hong Li, Hui Chao, Liang-Nian Ji, Xiong Jiang

Journal of Electrochemistry

The electrochemical characteristics and intermetallic interaction of symmetrical binuclear ruthenium(Ⅱ) complexes [Ru2:(bpy) 2Ru(DIPB)Ru(bpy) 2(ClO 4) 4 and Ru2_2H:(bpy) 2Ru(DIPB-2H)Ru(bpy) 2(ClO 4) 2 ]containing dinuclear ligand 2,2_bipyridine(bpy) and bridging ligand 1,4_di[2_imidazo[4,5_f][1,10] phenanthroine]benzene(DIPB) or 1,4_di[2_dehydrogen_imidazo[4,5_f][1,10] phenanthroine]benzene(DIPB_2H) on a platinum electrode have been investigated using cyclic voltammetry,cyclic ac voltammetry and differential capacitance techniques,etc.In acetonitrile solutions with a concentration of 0.1 mol/L TBAP,the central ruthenium ions in Ru2 and Ru2_2H complexes have shown a single 2e reversible oxidation_reduction wave on the cyclic voltammograms with basically the same formal potentials of Ru2_2H and Ru2 and a slightly larger apparent diffusion coefficient of the Ru2_2H complex …

Electrochemistry Characteristic Of Carbon Steel Under Biofilm And Sulfide Film, Ze-Hua Dong, Xing-Peng Guo, Jia-Shen Zheng, Li-Ming Xu

Journal of Electrochemistry

Wire Beam Electrode (WBE) made of Q235 carbon steel was applied to study the heterogeneous corrosion beneath biofilm formed by Sulfate Reducing Bacteria (SRB) in culture and sulfide film in solution with 1% NaCl and 300 mg/L S 2- . The potential,galvanic density mapping,as well as polarization curve and Electrochemical Impedance Spectrum (EIS) were measured to predict the localized corrosion under biofilm and sulfide film.As a result,the mapping showed the potential fluctuation on the WBE surface decreased over time due to the conductivity of the biofilm and sulfide film.Therefore,the potential mapping could not be a criterion of localized corrosion under …

Comparison In Surface Enhanced Raman Scattering On Salicylideneamine Between Silver And Gold Colloid And Silver Mirror Substrate, Zhao Bing, Yukihiro Ozaki

Journal of Electrochemistry

In recent years, the study of photochromic and thermochromic materials has grown because of their possible applications in the optical processing of information, in addition to the scientific interest. Salicylidineaniles is one of the prospective choices owing to their photochromism caused by intramolecular hydrogen transfer [1～3] (Fig.1). It is generally agreed that, in the salicylideneamine system, photoexcitation is followed by a rapid barrierless proton transfer and subsequent rearrangement to form a colored photoproduct [4] . The photochemistry of the system in fluid solution is different from that of the solid, even in fluid solution, the photo? and thermo?chromic behavior is …

Performance Of Proton Exchange Membrane Fuel Cell With Co/H_2 Fuel, Hong-Mei Yu, Zhong-Jun Hou, Bao-Lian Yi, Ke-Wan Bi, Jing-Xin Zhang, Zhi-Yin Lin, Ming Han

Journal of Electrochemistry

Fuel of proton exchange membrane fuel cell(PEMFC) mostly comes from reformate contains CO which will poison the fuel cell electrocatalyst.The effect of CO on the performance of PEMFC was studied in this paper.The results of the experiment show that when CO is fed in PEMFC,the cell voltage will be decreased violently,then it will become steady with some vibration.The poison will become more serious with higher CO content and weaker at higher temperature.The adsorption of CO on the electrocatalyst is reversible. The PtRu electrocatalyst is more suitable for the electrocatalysis of CO/H 2 than Pt electrocatalyst.

Atmospheric Corrosion Of Steels In China, Cai-Feng Liang

Journal of Electrochemistry

Data of eight year atmospheric exposures of 17 steels at 7 sites in China were analyzed.The result showed that the most detrimental pollution is sulfur dioxide and chloride ion for corrosion of carbon steels and low alloy weathering steels.This is in accordance with the common knowledge.The effect of sulfur dioxide is serious in the first few years and becomes weak obviously in the later years.The environment factor of humid hot is much more important in long run than the ordinarily acknowledged humidity,pollution for non weathering steels,although it is not obvious in the beginning.If pollution were existed,a severe corrosion may resulted.As …

Galvanic Corrosion Of Tin-W Electro-Couple During Tungsten Chemical Mechanical Polishing, Xuan Cheng, Chang-Jian Lin

Journal of Electrochemistry

Chemical_mechanical polishing (CMP) is a process whereby mechanical and chemical forces are combined to remove material from a wafer and polish it to a flat surface. Tungsten CMP is an important process to gain the global planarity of silicon wafers with tungsten (W) plugs. Tungsten is actually deposited on a thin adhesive layer of titanium nitride (TiN) on silicon. When close to the final stage of polishing, TiN and W will be simultaneously exposed to the polishing chemistry, forming a galvanic couple. The corrosion of TiN and W couple will result in different polish rate. This work studied the potential …

Preparation Of Ti-Based Nanocrystalline Tio_2 Film Electrode With High Activity, Dao-Bao Chu, Guang-Xia Shen, Xing-Fu Zhou, Chang-Jian Lin, Hua-Shui Lin

Journal of Electrochemistry

The potentiostatic electrosynthesis of Ti(EtO) 4 was studied by anodic dissolution of metal titanium(TA1) in solution of 0.005 mol·L -1 (EtO) 4NBr in the ethanol (AR) in the presence negligible CH 3COCH 2COCH 3.The Ti_based nanocrystalline TiO 2 Film electrode (Ti/nano_TiO 2) was prepared by sol_gel method.By TEM,SEM and XRD,it has been shown that the anatase particle of TiO 2 was 10～35 nm in diameter and the film was 0.5 μm in thickness.The nanocrystalline film was composed of a three_diminsional network of interconnected particles.Reodx behavior and electrocatalytic activities of the Ti/nano_TiO 2 electrode were investigated by cyclic voltammetry (CV) from …

Properties Of Metallized Poly-O-Toluidide Membrane Modified Electrode, Li-Zong Dai, Yi-Ting Xu, Hui-Huang Wu

Journal of Electrochemistry

The platinum particles were electrodeposited on poly(o_toluidide),POT,modified electrode,and the surface configuration and crystal orientation of Pt particles were investigated by SEM and XRD.At the same time the oxidation of isopropanol on platinized POT modified electrode was studied.The results indicate that Pt particles deposite towards preferred_orientation;moreover the increase in polymer electroactivity due to proton doping affects the dimension and graininess of deposited Pt particles.At the metallized polymer electrode the oxidation of isopropanol can occur in POT electroactive potential region,however at the more positive than 0.70 V (SCE) potential where POT loses redox activity the electro_oxidation mainly occurrs on Pt particles.It follows …

Preparation And Properties Of Separator For Lithium-Ion Battery, Xu-Mei Ren, Feng Wu, Chuan Wu, Han-Jun Li, Xue-Jie Huang

Journal of Electrochemistry

Lithium_ion batteries are well adapted to the new multimedia applications. PP/PE based microporous film is commonly used as separator in commercial lithium ion batteries. Here we report a microporous film which is superior to the commercial available separator. The microporous PVDF polymer separators were prepared by the phase inversion process. The pore size of the separator is  7 μm, and it's porosity is 75%. The membrane in LiPF 6 EC/DEC showed high ionic conductivity (above 10 -3 S/cm at room temperature), and good mechanical properties (10 3 kg/cm 2). The half_cells consisted of Li/PVDF separator/MCMB showed excellent cycling characteristics …

The Effect Of Calcium On The Properties Of Molybdenum Nitride Electrode, Yun-Gui Zhu, Xue-Liang Li, Dao-Rong Lu, Jian-Bo He, Ji-Huai Xia

Journal of Electrochemistry

The effect of calcium on the properties of molybdenum nitride film electrode was studied by using XRD, SEM and cyclic voltammetry. The results show that the specific electric capacity and the voltage operating range of electrode vary with the concentration of additive in the dipping solution. At the optimum concentration of additive in the dipping solution, the specific electric capacity of the electrode is 2.1 times as large as that of the electrode prepared in the dipping solution without additive, and the voltage operating range of electrode is increased by 0.11 V. The active mechanism of calcium on the properties …

Study On Corrosion Resistance Of Electroless Nickel Composite Coatings, Tsong-Jen Yang, Meng-Feng Jou

Journal of Electrochemistry

The eletroless nickel composite coating was prepared by uniform dispersion of diamond (or PTFE) particles throughout electroless nickel deposition. Corrosion resistance of composite coating in 3.5% NaCl aqueous solution was investigated by electrochemical analysis, dipping test and salt spray test. The results showed that the corrosion resistance of composite coating was inferior to that of electroless nickel coating if small amount of particles was added to the composite coating. Microsturctural analysis by SEM,AES,XRD,and EPMA indicated that the distribution of phosphorus is not homogeneous in the composite coating. The phosphorus_rich region acts as microcathode, however, the phosphorus_lean region acts as microanode.The …

Study Of The Oxidation Dynamics Of Ti-Zro_2 Metal-Ceramics, Wen-Chao Li, Li-Dong Teng

Journal of Electrochemistry

The oxidation dynamics of hot pressed Ti ZrO 2 metal_ceramics with the composition of 50 vol.% Ti and 50 vol.% ZrO 2 has been studied. Thermodynamic analysis shows that Ti could react with O 2 but not with N 2 in the oxidizing process of Ti ZrO 2 composites at 0.1 MPa air. The oxidation dynamic behavior of Ti ZrO 2 composites is analogous to that of pure Ti. The activation energy for the oxygen diffusion in Ti ZrO 2 composites is higher than that in Ti solutions, for the presence of ZrO 2 restrains the oxygen diffusion in Ti …

Electrochemical Behavior Of Tinicu Shape Memry Alloy In Simulated Body Fluid, Cheng-Hao Liang, Hong-Yan Sui

Journal of Electrochemistry

The study of TiNiCu shape memory alloys(SMA) in Hank's simulated body fluid was carried out.The results showed that narrow passive range was found in acid environment and active anodic dissolution was discovered at 100～150 mV vs SCE on anodic polarization cure of TiNiCu SMA.Temperature had little effect on anodic polarization.With the decrease of pH and the increase of Cl - concentration,pitting corrosion potential ( E b) shifted negatively.The electrochemical capability of TiNiCu SMA was inferior to that of TiNi SMA.Observations by means of XRD and SEM indicate that TiNiCu SMA is not in single crystal structure,which caused irregular electrochemical behavior …

The Dependence Of Relative Enhancement Of Sers Bands On Temperature, Ling Huang, Jian Shen, Tsing Yu, Qing-Jin Meng

Journal of Electrochemistry

The adsorption and binding behavior of 2,5_dimercapto_1,3,4_thiadizole(DMTD) on silver surface was studied by near_infrared Fourier Transfer surface enhanced Raman scattering(NIR FT-SERS) technique. It was found that the relative intensities of the SERS bands change regularly with the increasing of temperature, which suggests the transformation of the tautomers or the re_orientation of DMTD molecules in the surface layer.

Corrosion Behavior Of Titanium In Fgd System, C Lin J, L Chang T, T Dung C, L Lee S, D Chyou S, S D Guo

Journal of Electrochemistry

In situ corrosion test of titanium in flue gas desulfurization(FGD)system has been studied.Specimens of commercial Ti alloy have been put in four different locations(i.e,cooler,prescruber,absorber and heater) of the FGD system for 271 days.The corrosion rate is very low(i.e.