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Articles 25681 - 25710 of 34747

Full-Text Articles in Physical Sciences and Mathematics

Effects On The Structure And Electrochemical Performance Of Lifepo_(4) By Zr~(4+) Doping, Yan-Li Ruan, Zhi-Yuan Tang Aug 2006

Effects On The Structure And Electrochemical Performance Of Lifepo_(4) By Zr~(4+) Doping, Yan-Li Ruan, Zhi-Yuan Tang

Journal of Electrochemistry

Stoichiometric Zr-doped lithium iron phosphate(LiFePO_(4)) cathode material was synthesized by a solid-state reaction in an inert atmosphere.The effects of doping content on the physical and electrochemical properties of as-synthesized cathode materials were investigated.The samples were characterized by powder X-ray diffraction(XRD),and their electrochemical performance was systematically measured by impedance response and constant current charge/discharge cycling tests.The results indicate that the low concentration Zr~(4+)doping does not affect the structure of the material but considerably improves its kinetics in terms of capacity delivery and cycle performance.At 0.1C discharging rate,the reversible specific capacities of the Li_(0.99)Zr_(0.01)FePO_(4)cathode material is 135.6mAh g~(-1).After 30 cycles,the capacity fade …

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Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo_(2), Hong-Lan Qi, Cheng-Xiao Zhang Aug 2006

Pre-Oxidative Amperometric Glucose Biosensor Incorporated With Carbon Nanotube And Pbo_(2), Hong-Lan Qi, Cheng-Xiao Zhang

Journal of Electrochemistry

A pre-oxidative amperometric glucose biosensor incorporated with carbon nanotube,ferrocenemonocarboxylic acid and PbO_(2) was designed.The interferences coming from reduced substances,such as ascoribic acid and urine acid were eliminated by PbO_(2).The oxidative current is linear at the potential of +0.40 V(vs.SCE) to the concentration of glucose in the range from 0.50 to 20 mmol·L~(-1),and the detection limit of glucose is 0.1 mol L~(-1).The relative standard deviation is 3.3% for seven successive assays at 5.0 mmol·L~(-1)glucose.This biosensors have been applied to determination of the glucose in serum with satisfying results.

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Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu Aug 2006

Study On The Preparetion And Electrochemical Beavior Of Nitrogen Doped Tetrahedral Amorphous Carbon Electrode, Ke Liu

Journal of Electrochemistry

taC∶N films are a good materials for semiconductor electrodes.But further studies are hampered by the ohmic contact problem,which occurs between the silicon and the lead.By studying the influence of heat treatment on the film's property,it is believed that ohmic contact should be made on the silicon first,and then the film be deposited.A set of taC∶N electrodes with various nitrogen content have been prepared.CV study indicates that the cathodic limits move slowly to positive direction.while the anodic limits are unchanged with the increasing of nitrogen content.As a result,the electrochemical windows get narrow either.

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Scaling And The Smoluchowski Equations, Jerry Goodisman, J. Chaiken Aug 2006

Scaling And The Smoluchowski Equations, Jerry Goodisman, J. Chaiken

Chemistry - All Scholarship

The Smoluchowski equations, which describe coalescence growth, take into account combination reactions between a j-mer and a k-mer to form a (j+k)-mer, but not breakup of larger clusters to smaller ones. All combination reactions are assumed to be second order, with rate constants K jk. The K jk are said to scale if K λj,γk =λ μγ μK jk for j ≤ k. It can then be shown that, for large k, the number density or population of k-mers is given by Ak ae -bk, where A is a normalization constant (a function of a, …

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Application Of Scaling And Kinetic Equations To Helium Cluster Size Distributions: Homogeneous Nucleation Of A Nearly Ideal Gas, J. Chaiken, Jerry Goodisman, Oleg Komilov, J. Peter Toennies Aug 2006

Application Of Scaling And Kinetic Equations To Helium Cluster Size Distributions: Homogeneous Nucleation Of A Nearly Ideal Gas, J. Chaiken, Jerry Goodisman, Oleg Komilov, J. Peter Toennies

Chemistry - All Scholarship

A previously published model of homogeneous nucleation [Villarica et al., J. Chem. Phys. 98, 4610 (1993)] based on the Smoluchowski [Phys. Z. 17, 557 (1916)] equations is used to simulate the experimentally measured size distributions of 4He clusters produced in free jet expansions. The model includes only binary collisions and does not consider evaporative effects, so that binary reactive collisions are rate limiting for formation of all cluster sizes despite the need for stabilization of nascent clusters. The model represents these data very well, accounting in some cases for nearly four orders of magnitude in variation in abundance over …

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Multicentered Integrated Qm:Qm Methods For Weakly Bound Clusters: An Efficient And Accurate 2-Body:Many-Body Treatment Of Hydrogen Bonding And Van Der Waals Interactions, Gregory S. Tschumper Aug 2006

Multicentered Integrated Qm:Qm Methods For Weakly Bound Clusters: An Efficient And Accurate 2-Body:Many-Body Treatment Of Hydrogen Bonding And Van Der Waals Interactions, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

An efficient integrated QM:QM technique for the description of weakly bound clusters is presented. The computational technique described here takes advantage of the recently developed multicentered (MC) integrated QM:QM methods and reliably describes hydrogen bonding and van der Waals interactions by treating all 2-body interactions with a high-level QM method and the many-body interactions with a low-level QM method. Even for small clusters of He, Ne, HF, and water, the MC QM:QM methods are typically 1-3 orders of magnitude faster than the high-level method while introducing an error of less than 1% in the interaction energy. © 2006 Elsevier B.V. …

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Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke Aug 2006

Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke

Electronic Theses and Dissertations

Cholesterol is an important biological molecule with many important functions. However, high serum cholesterol is a health hazard. Thus analysis of cholesterol is important and many analytical techniques have been developed. The objectives of the proposed research are to develop an economical, rapid method for the determination of total cholesterol with good selectivity and enhanced sensitivity. For evaluation of proposed flow injection analysis with peroxyoxalate chemiluminescence (FIA-POCL) method, figures of merit such as accuracy, precision, and linear dynamic range will be assessed. The proposed procedure was then applied to the determination of total cholesterol in foods. The procedure was linear …

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Polyaniline And Its Derivatives For Environmental Analysis., Atogho Jude Abia Aug 2006

Polyaniline And Its Derivatives For Environmental Analysis., Atogho Jude Abia

Electronic Theses and Dissertations

Electrooxidation has been used to deposit thin film polyaniline as well as its derivative - thin film poly (ortho-phenylenediamine) (POPD) and poly (meta-phenylenediamine) (PMPD) on carbon electrodes, which are subsequently used to monitor the environmental heavy metal ions (Hg2+, Pb2+ ,Cd2+) through a rather unusual "blocking" of anodic stripping for these metals. Using Hg2+ as a model, its cyclic voltammogram for a modified glassy carbon electrode with the resultant polymer shows an enhanced cathodic peak that increases linearly with the analyte ion concentration. POPD also exhibits unique selective detection for organic species. Acetaminophen and …

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Reversed-Phase Hplc Determination Of Citral In Locally Grown Lemon Grass Harvested At Different Season., Mahmoud Al-Shaer Aug 2006

Reversed-Phase Hplc Determination Of Citral In Locally Grown Lemon Grass Harvested At Different Season., Mahmoud Al-Shaer

Electronic Theses and Dissertations

A simple HPLC procedure for the quantitative determination of citral, the major fragrant component in the lemon grass, has been developed. The procedure involves a C-8 stationary phase using a 90:10 methanol: water pH 5 mobile phase containing 0.25% 1-octanesulfonic acid and an UV detector (set at 233 nm). The lemon grass leaves were harvested fresh at different times of the year and were soaked in methanol for 48 hours without any mechanical assistance to extract the citral and other methanol soluble components. The method showed good reproducibility with relative standard deviation of 2.8% and 10.8% for two different sets …

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The Structure And Thermochemistry Of 3:4,5:6-Dibenzo-2-Hydroxymethylene-Cyclohepta-3,5-Dienenone ( 1 ) And Some Related Compounds, Stefan Perişanu, Iulia Contineanu, Mircea D. Banciu, Hui Zhao, Nigam Rath, James Chickos Aug 2006

The Structure And Thermochemistry Of 3:4,5:6-Dibenzo-2-Hydroxymethylene-Cyclohepta-3,5-Dienenone ( 1 ) And Some Related Compounds, Stefan Perişanu, Iulia Contineanu, Mircea D. Banciu, Hui Zhao, Nigam Rath, James Chickos

James Chickos

No abstract provided.

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Tetrakis[2-(2-Pyridyl)Pyridinium] Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate And Bis[Tris(2,2'-Bipyridine)Ruthenium(Ii)] Di-Μ4-Iodo-Octa-Μ2-Iodo-Dodecaiodohexabismuthate, Andrea M. Goforth, Meredith A. Tershansy, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Aug 2006

Tetrakis[2-(2-Pyridyl)Pyridinium] Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate And Bis[Tris(2,2'-Bipyridine)Ruthenium(Ii)] Di-Μ4-Iodo-Octa-Μ2-Iodo-Dodecaiodohexabismuthate, Andrea M. Goforth, Meredith A. Tershansy, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

Crystals of the title compounds were grown solvothermally in an ethanol-water solvent mixture using ruthenium triiodide, 2,2'-bipyridine and bismuth triiodide as starting materials. Tetrakis[2-(2-pyridyl)pyridinium] tetra-3-iodo-hexa-2-iodo-dodecaiodohexabismuthate, (C10H9N2)4[Bi6I22], crystallizes in the triclinic space group P and is the major reaction product. The asymmetric unit of this compound consists of half a centrosymmetric [Bi6I22]4- anion and two independent 2,2'-bipyridinium cations. The minor product of the reaction is bis[tris(2,2'-bipyridine)ruthenium(II)] di-4-iodo-octa-2-iodo-dodecaiodohexabismuthate, [Ru(C10H8N2)3] …

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Europium(Iii) Macrocyclic Complexes With Alcohol Pendant Groups As Chemical Exchange Saturation Transfer Agents, Mark Woods, Donald E. Woessner, Piyu Zhao, Azhar Pasha, Meng-Yin Yang, Ching-Hui Huang, Olga Vasalatiy, Janet R. Morrow, A. Dean Sherry Aug 2006

Europium(Iii) Macrocyclic Complexes With Alcohol Pendant Groups As Chemical Exchange Saturation Transfer Agents, Mark Woods, Donald E. Woessner, Piyu Zhao, Azhar Pasha, Meng-Yin Yang, Ching-Hui Huang, Olga Vasalatiy, Janet R. Morrow, A. Dean Sherry

Chemistry Faculty Publications and Presentations

Paramagnetic lanthanide(III) complexes that contain hyperfine-shifted exchangeable protons offer considerable advantages over diamagnetic molecules as chemical exchange saturation transfer (CEST) agents for MRI. As part of a program to investigate avenues to improve the sensitivity of such agents, the CEST characteristics of europium(III) macrocyclic complexes having appended hydroxyethyl groups were investigated. The CEST spectrum of the asymmetrical complex, EuCNPHC3+, shows five distinct peaks for each magnetically nonequivalent exchangeable proton in the molecule. The CEST spectra of this complex were fitted to NMR Bloch theory to yield exchange rates between each of six exchanging proton pools (five on the …

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Ferritin: Mechanistic Studies And Electron Transfer Properties, Bo Zhang Aug 2006

Ferritin: Mechanistic Studies And Electron Transfer Properties, Bo Zhang

Theses and Dissertations

Ferritins are ubiquitous iron storage proteins in living systems. Although much is known about the iron deposition process in ferritin and a mechanism has been developed, several important issues still remain unknown. One lingering question is the less than stoichiometric quantities of hydrogen peroxide detected in previous studies on animal ferritins. Extensive experimental data on identifying the species in competition for peroxide equivalents point to a surprising conclusion that H2O2 generated in the ferroxidase reaction is consumed by amine buffers that are commonly employed in in vitro ferritin studies, while non-nitrogen containing buffers, such as acetate, phosphate, and carbonate, do …

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Shape-Dependent Molecular Recognition Of Specific Sequences Of Dna By Heterocyclic Cations, Yi Miao Aug 2006

Shape-Dependent Molecular Recognition Of Specific Sequences Of Dna By Heterocyclic Cations, Yi Miao

Chemistry Dissertations

SHAPE-DEPENDENT MOLECULAR RECOGNITION OF SPECIFIC SEQUENCES OF DNA BY HETEROCYCLIC CATIONS by YI MIAO Under the Direction of Dr. W. David Wilson ABSTRACT DB921 and DB911 are biphenyl-benzimidazole-diamidine isomers with a central para- and meta-substituted phenyl group, respectively. Unexpectedly, linear DB921 has much stronger binding affinity with DNA than its curved isomer, DB911. This is quite surprising and intriguing since DB911 has the classical curved shape generally required for strong minor groove binding while DB921 clearly does not match the groove shape. Several biophysical techniques including thermal melting (Tm), circular dichroism (CD), biosensor-surface plasmon resonance (SPR), and isothermal titration calorimetry …

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Crystal And Molecular Structure Of Bis(8-Phenylmenthyl) 2-(2-Methyl-5-Oxo-3-Cyclohexen-1-Yl)Propandioate, C42H54O5• Ch3Cn, Dennis W. Bennett, Tasneem A. Siddiquee, Daniel T. Haworth, Subhabrata Chaudhury, William Donaldson Aug 2006

Crystal And Molecular Structure Of Bis(8-Phenylmenthyl) 2-(2-Methyl-5-Oxo-3-Cyclohexen-1-Yl)Propandioate, C42H54O5• Ch3Cn, Dennis W. Bennett, Tasneem A. Siddiquee, Daniel T. Haworth, Subhabrata Chaudhury, William Donaldson

Chemistry Faculty Research and Publications

The X-ray crystal structure of the title compound, as crystallized from acetonitrile-water was determined. The relative stereochemistry of the cyclohexenone ring with respect to the 8-phenylmenthyl esters was determined. The title compound crystallizes in the noncentrosymmetric space group P21, with a=8.9850(10) Å, b=15.575(3) Å, c=14.478(2) Å, β=94.61(2)°, and D calc=1.118 g cm−3 for Z=2.

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Hybrid Atomistic-Coarse-Grained Treatment Of Multiscale Processes In Heterogeneous Materials: A Self-Consistent-Field Approach, Dennis J. Diestler, H. Zhou, Ruqiang Feng, Xiao Cheng Zeng Aug 2006

Hybrid Atomistic-Coarse-Grained Treatment Of Multiscale Processes In Heterogeneous Materials: A Self-Consistent-Field Approach, Dennis J. Diestler, H. Zhou, Ruqiang Feng, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A treatment of multiscale quasistatic processes that combines an atomistic description of microscopic heterogeneous (“near”) regions of a material with a coarse-grained (quasicontinuum) description of macroscopic homogeneous (“far”) regions is presented. The hybrid description yields a reduced system consisting of the original atoms of the near regions plus pseudoatoms (nodes of the coarse-graining mesh) of the far regions, which interact through an effective many-body potential energy Veff that depends on the thermodynamic state. The approximate nature of Veff gives rise to “ghost forces,” which are reflected in spurious heterogeneities close to interfaces between near and far regions. The …

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The Harmonic Oscillator, The Hermite Polynomial Solutions, Carl W. David Aug 2006

The Harmonic Oscillator, The Hermite Polynomial Solutions, Carl W. David

Chemistry Education Materials

The Hermite polynomial solution to the simple harmonic oscillator is discussed.

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The Harmonic Oscillator, The Ladder Operator Solutions, Carl W. David Aug 2006

The Harmonic Oscillator, The Ladder Operator Solutions, Carl W. David

Chemistry Education Materials

The ladder operator approach to the quantum mechanics of the simple harmonic oscillator is presented.

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Oxidative Carbonylation And Conjugated Processes With Carbon Monoxide Participation Catalyzed By Palladium Complexes (In Russian), Lev G. Bruk, Irina V. Oshanina, Sergey N. Gorodsky, Oleg N. Temkin Aug 2006

Oxidative Carbonylation And Conjugated Processes With Carbon Monoxide Participation Catalyzed By Palladium Complexes (In Russian), Lev G. Bruk, Irina V. Oshanina, Sergey N. Gorodsky, Oleg N. Temkin

Sergey N. Gorodsky

No abstract provided.

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Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry Aug 2006

Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry

Kraig A. Wheeler

In the title mol­ecular salt, C21H23N2O2+·C9H8BrO3−·1.4H2O, the components are linked by inter­molecular C—O−⋯H—+N and OW—H⋯O inter­actions.

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Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker Aug 2006

Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

More than 1 000 000 people are diagnosed with skin cancer each year in the United States, and more than 10 000 people die from the disease. Methods such as visual inspection and dermoscopy are available for early detection of skin cancers, but improvement in accuracy is needed. This paper investigates the use of microwave reflectometry as a potential diagnostic tool for detection of skin cancers. Open-ended coaxial probes were used to measure microwave properties of skin. The influences of measurement parameters such as probe application pressure, power level, and variation in reflection properties of skin with location and hydration …

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Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry Aug 2006

Strychninium (S)-2-(2-Bromo­Phen­Oxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry

Faculty Research and Creative Activity

In the title mol­ecular salt, C21H23N2O2+·C9H8BrO3−·1.4H2O, the components are linked by inter­molecular C—O−⋯H—+N and OW—H⋯O inter­actions.

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Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor Aug 2006

Implications Of Mass Education On Chemistry Higher Education, Christine O'Connor

Articles

The following paper discusses the implications of government policy for widening access and participation in third level institutes. The increase in ‘non-traditional’ students has been widely recognised on an international scale; however, some issues of inequality still exist. The ‘struggles’ associated with widening participation and the creation of a ‘new’ student type are discussed, with particular reference to chemistry education. A change is needed with regard to the pedagogical approach taken by staff in order to cater for a diverse student body comprising a broad range of learner types, and this must be supported both at departmental and institutional levels. …

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Water Solubility Characteristics Of Hydrophobically Modified Polyethyleneimines, Jennifer N. Williams Aug 2006

Water Solubility Characteristics Of Hydrophobically Modified Polyethyleneimines, Jennifer N. Williams

Browse all Theses and Dissertations

Commercially available polyethyleneimines varying in molecular weights and viscosities were synthetically modified in order to increase their hydrophobicity when dissolved in water. Used as additives for inkjet industry inks, these polymers have been designed to promote interaction between formulated inks and paper, while increasing the water-fastness of these water-soluble inks once they are dried on bond paper. Waterfastness, the ability of an ink to maintain print integrity once it becomes wet, as well as optical density, solubility, pH, molecular weight, polydispersity and viscosity are amongst the characteristics analyzed. The modifications of these polyethyleneimines (PEis) with alkyl bromides and alkyl epoxides …

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Investigation Of The Suitability Of The Biscatecholborate Anion As A Reductive Quencher For Photoexcited Ruthenium Polyphyridyl Complexes, Alper Yarasik Aug 2006

Investigation Of The Suitability Of The Biscatecholborate Anion As A Reductive Quencher For Photoexcited Ruthenium Polyphyridyl Complexes, Alper Yarasik

Chemistry & Biochemistry Theses

Ruthenium polypyridyl complexes [Ru(L-L)3]2+, (L-L = 1,10 - phenanthroline or 2,2'- bipyridine) which covalently linked to electron donor or acceptor units are frequently used in artificial photosystems because of their high emission quantum yields, long excited-state lifetimes, favorable redox properties and excellent chemical stability. The ruthenium dimer P, [(phen)2Ru(tatpp)Ru(phen)2][PF6]4, undergoes multiple photoreductions in the presence of donors such as triethylamine (TEA); however, large amount of donors (0.3 M) are required for efficient reductions. This explores the use of a anionic donor such as [B(cat)2]- with the hypothesis that ion-pairing will result in lower required concentration of the donor. Electrochemical data …

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Nanostructured Layered Copper Hydroxy Dodecyl Sulfate: A Potential Fire Retardant For Poly(Vinyl Ester) (Pve), Everson Kandare, Grace Chigwada, Dongyan Wang, Charles A. Wilkie, Jeanne Hossenlopp Aug 2006

Nanostructured Layered Copper Hydroxy Dodecyl Sulfate: A Potential Fire Retardant For Poly(Vinyl Ester) (Pve), Everson Kandare, Grace Chigwada, Dongyan Wang, Charles A. Wilkie, Jeanne Hossenlopp

Chemistry Faculty Research and Publications

Composites of poly(vinyl ester) (PVE) with copper hydroxy dodecyl sulfate (CHDS) were prepared by thermal curing. The efficiency of the additive, CHDS, in reducing flammability is demonstrated via cone calorimetry and thermogravimetric analysis (TGA). The addition of 1-10% by mass of the CHDS additive resulted in significant increments in char formation (~4-11%) from thermogravimetric analysis (TGA). Incorporation of the CHDS into the polymer matrix at these low concentrations leads to substantial reductions in the total heat release (~20-30%) but no significant change in the peak heat release rate. The composite materials generally ignite more quickly, however, the flame extinguishes faster …

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Synthesis Of Lanthanum-Strontium Manganites By Oxalate-Precursor Co-Precipitation Methods In Solution And In Reverse Micellar Microemulsion, Vuk Uskoković, Miha Drofenik Aug 2006

Synthesis Of Lanthanum-Strontium Manganites By Oxalate-Precursor Co-Precipitation Methods In Solution And In Reverse Micellar Microemulsion, Vuk Uskoković, Miha Drofenik

Pharmacy Faculty Articles and Research

Nanostructured lanthanum–strontium manganites were synthesized using two different co-precipitation approaches, one in bulk solution, and the other in reverse micelles of CTAB/1-hexanol/water microemulsion. In both cases, precursor cations were precipitated by using oxalic acid. The properties of the materials synthesized by using these two methods were compared in order to reveal potential advantages of the microemulsion-assisted approach. The influence of the annealing conditions on the properties of synthesized manganites was investigated by using X-ray diffraction, transmission electron microscopy, differential thermal analysis, thermogravimetric analysis and magnetic measurements.

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Pseudostationary Phase For Solid Phase Extraction, Qing Zhao Aug 2006

Pseudostationary Phase For Solid Phase Extraction, Qing Zhao

Masters Theses & Specialist Projects

A unique pseudostationary phase for Solid Phase Extraction is presented. This pseudostationary phase consists of surfactant, which is initially immobilized onto hydrophilic cation exchange resin. The surfactant chain through hydrophobic interactions extracts hydrophobic analytes in the same manner as conventional bonded alkyl moieties on silica based non-polar sorbents. Although hydrophobic analytes can be efficiently trapped on commercially available non-polar sorbents (i.e. Ci8 silica), organic solvents that are necessary to break strong hydrophobic interactions between the analytes and the sorbent are harmful. They are also incompatible for direct introduction into a reversed phase liquid chromatographic set up. In the presented approach, …

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4,4′-(1,1,1,3,3,3-Hexafluoro­Propane-2,2-Diyl)Bis­(Benzoyl Chloride), Cecilia Rodriguez De Barbarin, Sylvain Bernes, Javier Macossay-Torres, Patrick E. Cassidy Aug 2006

4,4′-(1,1,1,3,3,3-Hexafluoro­Propane-2,2-Diyl)Bis­(Benzoyl Chloride), Cecilia Rodriguez De Barbarin, Sylvain Bernes, Javier Macossay-Torres, Patrick E. Cassidy

Chemistry Faculty Publications and Presentations

In the structure of the title mol­ecule, C17H8Cl2F6O2, the dihedral angle between the least-squares planes of the benzene rings is 66.31 (15)°. The CF3 groups adopt an eclipsed conformation.

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Novel Approaches To Photoassisted Deposition Of Semiconductors And Nanocomposite Materials, Sashikala Somasundaram Aug 2006

Novel Approaches To Photoassisted Deposition Of Semiconductors And Nanocomposite Materials, Sashikala Somasundaram

Chemistry & Biochemistry Dissertations

This dissertation research begins with the use of TiO2-based photocatalysis for the reduction of metal ions with very negative reduction potentials. The indirect photocatalytic reduction of four metal ions: Cd2+, Zn2+, Mn2+, and Tl+ using formate radical anions generated in UV-irradiated aqueous TiO2 suspensions, is described. Using Tl+ as a model metal ion, a simple kinetics scheme was developed for the indirect reduction route, and the predictions from this model were shown to be in excellent agreement with experimental data. Titania-based photocatalysis was then used for the preparation of MSe/TiO2 "coupled" semiconductors. Heterogeneous photocatalysis using photoexcited TiO2 substrates was shown …

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