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Articles 12271 - 12300 of 12788
Full-Text Articles in Entire DC Network
Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer
Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer
Biological Sciences Theses & Dissertations
Four experiments were performed to determine the ability of marine higher fungi to grow in and degrade crude oil. Eight species, previously determined to be hydrocarbonoclastic, were grown in artificial sea water medium (ASM) and southern Louisiana crude oil. The dry mycelial weights were measured and consumption of crude oil was measured gravimetrically. The two species with the best growth, Corollospora maritima and Zalerion maritimum, were grown in ASM containing crude oil spiked with three known hydrocarbons. To this was added glucose (0.15%) and incubated 49 days to test for possible cometabolism of hydrocarbons. Hydrocarbons remaining in the growth …
Development Of A System For Survey Of Radon Concentration Of The Dayton Area Using A Liquid Scintillation Counter And Analysis Of The Data, Taewon Kim
Theses and Dissertations
A system to do a large scale survey was developed. The data obtained from the survey was analyzed using a database. The database incorporated an equation for converting cpm into radon concentration pCi/ℓ). The equation of conversion, protocol for measuring radon concentration, survey form, and a database program were modified (from previous theses) or developed for this thesis. The elution time constant, adsorption time constant, and calibration factor were calculated for equation of conversion. Two surveys were during the course of the thesis. On the first survey, the arithmetic average radon concentration with standard error of the mean was 2.9 …
Determining The Chemical Composition Of Cloud Condensation Nuclei, Allen L. Williams, Jane E. Rothert, Kent E. Mcclure, Darryl J. Alofs, Donald E. Hagen, Daniel R. White, A. R. Hopkins, Max B. Trueblood
Determining The Chemical Composition Of Cloud Condensation Nuclei, Allen L. Williams, Jane E. Rothert, Kent E. Mcclure, Darryl J. Alofs, Donald E. Hagen, Daniel R. White, A. R. Hopkins, Max B. Trueblood
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This second progress report describes the status of the project one and one-half years after the start. The goal of the project is to develop the instrumentation to collect cloud condensation nuclei (CCN) in sufficient amounts to determine their chemical composition, and to survey the CCN composition in different climates through a series of field measurements. Our approach to CCN collection is to first form droplets on the nuclei under simulated cloud humidity conditions, which is the only known method of identifying CCN from the background aerosol. Under cloud chamber conditions, the droplets formed become larger than the surrounding aerosol, …
Characterization Of Low Pressure Chemical Vapor Deposited Silicon Dioxide Thin Films, Xue Du
Characterization Of Low Pressure Chemical Vapor Deposited Silicon Dioxide Thin Films, Xue Du
Theses
LPCVD deposited amorphous silicon dioxide SiO2 thin films from a new chemical vapor source, diethylsilane (DES), were characterized. This work is focused on evaluation of SiO2 films prepared by varies deposition temperatures and flow rates series.
SiO2 thin films were evaluated for density, porosity, and refractive index. Techniques for evaluation of the above mentioned parameters for this work included the use of infrared absorption spectroscopy, preferential etch procedures, optical measurement of refractive index and thickness, and thermal annealing of CVD films. The densification in vacuum ambient has been carried out at the temperature of 600 °, 750 …
Selective No Absorption From Gas Streams With Tertiary Organic Hydroperoxide Solutions, Huihong Ao
Selective No Absorption From Gas Streams With Tertiary Organic Hydroperoxide Solutions, Huihong Ao
Theses
The selective removal of nitric oxide from gas streams was investigated using 3,6-dimethyl-3-octyl hydroperoxide, p-menthane hydroperoxide, pinane hydroperoxide, and cumene hydroperoxide in solutions of n-hexadecane (cetane). The influence of different parameters such as temperature, gas stream flow rate (or residence time), and concentration of hydroperoxide compounds on efficiency of NO removal was evaluated. The basis of this research was to duplicate atmospheric reactions between hydroperoxides and NO in order to produce NO2. We succeeded in removing NO from gas streams, but failed to produce NO2. NO reacted with the hydroperoxides to produce nitrates. These nitrates are …
I. Removal Of Chromium From A Highly Contaminated Soil/Slag Matrix By Soil Washing At Low Ph, Ii. Removal Of Chromium From Impregnated Clay Matrices By Soil Washing At Low Ph, Erez Gotlieb
Theses
Section I. Chromium is a major soil contaminant of industrial sites in New Jersey, as well as in many of the Superfund sites throughout the United States. Removal of chromium by soil/slag washing with low pH sulfuric acid solutions is described. The extraction parameters are acid concentration, contact time, temperature, solvent/soil ratio, and acid type. The effect of two-stage extraction is discussed.
Soil/slag washing with sulfuric acid concentrations of 2% weight:volume (units are g/ml. This concentration is approximately equal to 0.4 N) at 75:1 v:w solvent/soil ratios yielded chromium extraction efficiencies of 95%, but 50% of the soil matrix was …
1-Ferrocenyl-1-Cyclopropyl Cation: The First Long-Lived Cyclopropyl Cation, G. K.Surya Prakash, Herwig Buchholz, V. Prakash Reddy, Armin De Meijere, George A. Olah
1-Ferrocenyl-1-Cyclopropyl Cation: The First Long-Lived Cyclopropyl Cation, G. K.Surya Prakash, Herwig Buchholz, V. Prakash Reddy, Armin De Meijere, George A. Olah
Chemistry Faculty Research & Creative Works
No abstract provided.
Characterizations Of Antimony Tri‐Sulfide Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal
Characterizations Of Antimony Tri‐Sulfide Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal
Faculty Publications
No abstract provided.
Hydration Behavior Of Laser Dye Aerosols Of Mixed Composition Having High Critical Supersaturations, Max B. Trueblood, Donald E. Hagen, Darryl J. Alofs
Hydration Behavior Of Laser Dye Aerosols Of Mixed Composition Having High Critical Supersaturations, Max B. Trueblood, Donald E. Hagen, Darryl J. Alofs
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This Study Concerns Aerosol Particles of Mixed Composition. the Particles Contain a Water Insoluble Core (Polystyrene Latex), Surrounded by a Water Soluble Shell (Various Fluorescent Dyes). a Collison Nebulizer and an Electrostatic Aerosol Classifier Are Used to Prepare the Aerosol; its Critical Supersaturation Spectrum is Measured with a Diffusion Cloud Chamber. Experiments Were Done using Four Different Dyes (Disodium Fluorescein, Sulforhodamine 640, Sulforhodamine B and Rhodamine 560 Chloride) with Five Different Polystyrene Latex Sphere Sizes. the Results Indicate that a Kohler-Type Behavior is Obeyed. This Technique of Putting a Soluble Coating Onto an Insoluble Core is Found to Be a …
Magnetic Properties Of A Novel Iron Carbide Film, Fe₇C₃X Formed In A Glow Discharge, Oran Allan Pringle, Gary J. Long, Fernande Grandjean, Jun L. Li, George C. Hadjipanayis, William Joseph James
Magnetic Properties Of A Novel Iron Carbide Film, Fe₇C₃X Formed In A Glow Discharge, Oran Allan Pringle, Gary J. Long, Fernande Grandjean, Jun L. Li, George C. Hadjipanayis, William Joseph James
Physics Faculty Research & Creative Works
No abstract provided.
Structural Studies Of Rare Earth-Iron Nitrides By Neutron Powder Diffraction, William B. Yelon, George C. Hadjipanayis
Structural Studies Of Rare Earth-Iron Nitrides By Neutron Powder Diffraction, William B. Yelon, George C. Hadjipanayis
Physics Faculty Research & Creative Works
No abstract provided.
Fundamental Aspect And Behavior Of Saturated Fluorocarbons In Glow Discharge In Absence Of Potential Source Of Hydrogen, Yu Iriyama, H. Yasuda
Fundamental Aspect And Behavior Of Saturated Fluorocarbons In Glow Discharge In Absence Of Potential Source Of Hydrogen, Yu Iriyama, H. Yasuda
Chemistry Faculty Research & Creative Works
The glow discharge of a series of saturated fluorocarbons, CnF2n+2 (n = 1, 2, 4, 6, and 8), was studied with glass substrates which do not contain any hydrogen. It was found that the deposition rate was a function of the F/C ratio of the starting fluorocarbons. That is, fluorocarbons with higher F/C ratio, such as CF4 and C2F6, hardly polymerized, while fluorocarbons with lower F/C ratio, such as C8F18, polymerized as well as C2F4. After plasma exposure, the surface of glass substrate was …
Experiments In Aerobic And Anaerobic Biodegradation Of Trichloroethylene, Qiong Liao
Experiments In Aerobic And Anaerobic Biodegradation Of Trichloroethylene, Qiong Liao
Theses
The removal of trichloroethylene (TCE) from industrial waste has been intensively studied in recent years, Biodegradation has been determined to be an effective treatment for TCE in the environment. Many researchers have studied the biodegradation of TOE and obtained successful results based on the use of specific isolated bacteria. At the NJIT Biotechnology Laboratory, a new method is being developed in which immobilized activated sludge is used to degrade several toxic chemicals in various reactor configurations. The objective of this research is to determine if these methods can be extended to treat TCE.
Activated sludge from a wastewater treatment plant …
Ua66/7/2 Hilltopper News, Wku Chemistry
Ua66/7/2 Hilltopper News, Wku Chemistry
WKU Administration Documents
Newsletter created by and about the WKU Chemistry department.
Thermal Characterization Of Carbon Monoxide Oxidation Catalysts Using Thermogravimetric Analysts And Differential Scanning Calorimetry, Rene A. Bartgis
Thermal Characterization Of Carbon Monoxide Oxidation Catalysts Using Thermogravimetric Analysts And Differential Scanning Calorimetry, Rene A. Bartgis
Chemistry & Biochemistry Theses & Dissertations
Catalysts composed of platinum and/or palladium on tin (IV) oxide supports, with and without silica gel, as well as catalysts composed of gold on manganese oxide, have been developed for the recombination of carbon monoxide and oxygen to form carbon dioxide for use in carbon dioxide lasers. A thermogravimetric method and a differential scanning calorimetric method have been developed for the thermal characterization of these catalysts. The mass loss data and the enthalpy changes determined as the catalysts lost water were then related to existing activity data for these catalysts. No relationship was found between the thermal data and the …
Low Pressure Chemical Vapor Deposition (Lpcvd) Of Silicon Carbide From Diethylsilane, Yi-Tong Shi
Low Pressure Chemical Vapor Deposition (Lpcvd) Of Silicon Carbide From Diethylsilane, Yi-Tong Shi
Theses
The depositions of amorphous and cubic-crystal SiC from a new chemical vapor deposition source, diethylsilane(DES), have been studied. Amorphous SiC thin films and crystalline cubic-SiC materials have been deposited on silicon wafers at temperature lower and higher than 850C, respectively. The activation energy and a reaction mechanism involving the production and subsequent desorption of diethylsilene has been suggested, which explains the observed deposition dependency with the temperature and reactor pressure. A model based on the polymerization of DES is offered and the deposition rate is found to be the result of a large number of simultaneously occuring deposition processes for …
Low-Temperature Crosslinking Of Polycyclopentadiene, Lawrence Peters
Low-Temperature Crosslinking Of Polycyclopentadiene, Lawrence Peters
Theses
Cyclopentadiene was polymerized via a Diels-Alder mechanism at 174°C under an inert atmosphere. The polymer obtained after ll hrs of reaction had a low bulk viscosity of 8 cps and a viscosity-average molecular weight, Mv, of up to 3000. An unsaturated polyester was synthesized from maleic anhydride and ethylene glycol in the presence of chlorosulfonic acid at room temperature. The polyester had an intrinsic viscosity of 0.024 cps. At 60°C, polycyclopentadiene (PCPD), and the unsaturated polyester were reacted to yield a viscous liquid which was crosslinked at room temperature over 48 hours in the presence of styrene, triethyleneglycol dimethacrylate (TEGDMA), …
On-Road Remote Sensing Of Co Emissions In The Los Angeles Basin, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Paul L. Guenther
On-Road Remote Sensing Of Co Emissions In The Los Angeles Basin, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Paul L. Guenther
Fuel Efficiency Automobile Test Publications
Final report to the California Air Resources Board under Contract No. A932-189.
The University of Denver remote sensor for on-road motor vehicle carbon monoxide emissions was used for eleven days in the Los Angeles Basin in December, 1989. The remote sensor has been incorporated into the 1990 Clean Air Act Amendments as "on-road emissions testing". The device measures the CO/CO2 ratio for one-half second behind each vehicle, from which the exhaust %CO is calculated. Vehicles were measured in a mix of many driving modes and speeds ranging from deceleration coming up to a red traffic light through idling in …
33rd Rocky Mountain Conference On Applied Spectroscopy
33rd Rocky Mountain Conference On Applied Spectroscopy
Rocky Mountain Conference on Magnetic Resonance
Program and registration information for the 33rd annual meeting of the Rocky Mountain Conference on Applied Spectroscopy, sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 28 - August 1, 1991.
Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang
Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang
Chemistry Faculty Publications
The third-order (pi) -electron polarizability, (gamma) (pi), of bacteriorhodopsin in the 0.0 - 1.2 eV optical region is assigned based on an analysis of the experimental two-photon properties of the low-lying singlet state manifold. The following selected values of (gamma) (pi) (units of 10-36 esu) are observed: (gamma) (0;0,0,0) equals 2482 +/- 327; (gamma) (-3(omega) ;(omega) ,(omega) ,(omega) ) equals 2976 +/- 385 ((omega) equals 0.25 eV), 5867 +/- 704 ((omega) = 0.5 eV), 14863 +/- 1614 ((omega) = 0.66 eV), 15817 +/- 2314 ((omega) equals 1.0 eV), 10755 +/- 1733 ((omega) equals 1.17 eV). The third-order polarizability of this …
Reactivities Of Some Aromatic Compounds At Supercritical Water Conditions, Chun-Cheng Tsao
Reactivities Of Some Aromatic Compounds At Supercritical Water Conditions, Chun-Cheng Tsao
Masters Theses
The goals of this study are the removal of nitrogen from the extraction products of coal by Supercritical Water and the development of an understanding of the reactions leading to this removal. Six model compounds with structures similar to the intermediates of the coal liquefaction processes were studied. Benzylamine generated toluene through hydrogen abstraction after the C-N bond rupture. To a lesser extent, the oxidation of the benzylic carbon took place leading to benzene formation. Both reaction pathways occurred with equal probability for benzylidenebenzylamine, producing comparable yields of benzene and toluene. Benzaldehyde generated benzene through the oxidation/decarboxylation sequence. Benzyl alcohol …
Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng
Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng
Theses
The determination of trace levels of organic compounds in water samples is well developed for the less polar compounds, but the polar compounds are more difficult. The development of reliable and reproducible methods for such compounds as volatile alcohols and ketones is necessary if environmental monitoring is to be extended to these compounds.
The purge-and-trap method is frequently used for determination of volatiles in water samples. The method has problems when hydrophylic substances are being analyzed, since these are less easy to purge from the solution and more difficult to trap and desorb quantitatively. The high amount of water carried …
Preparation And Testing Of Novel Dental Adhesives Based On Bis- Gma/Tegdma Monomer System, Deyun Sun
Preparation And Testing Of Novel Dental Adhesives Based On Bis- Gma/Tegdma Monomer System, Deyun Sun
Theses
In this study, polymerizable phosphonate adhesives synthesized from Diethylchloro-phosphate and 2-Hydroxyethylmethylacrylate and formulated with G-methacryloxy-propyltrimethoxy silane is used in Bis-GMA/TEGDMA monomer system. All the raw materials and finished products are characterized with infrared spectra, vapor pressure osmometry, viscosity and gel test. The bonding strength to tooth materials is determined by Instron machine. The work emphasizes applying polymeric organic phosphonate adhesive to Bis-GMA/TEGDMA monomer system and investigates the appropriate conditions for the crosslinking of Bis-GMA/TEGDMA monomer system. Average bonding strength of 744 psi to enamel and 600 to dentine are ob¬tained in comparision to 550 psi to enamel for phosphonate/silane/MMA/PMMA and …
The Limitations Of Women In Science At Six Midwestern Colleges Due To The Adherence To Conceptions Of Gender Differences Between The Sexes In The Years Of 1880 Through 1940, Denise Mohney '91
Honors Projects, History
It is difficult for college students today to imagine life when the term "discrimination" had not yet been defined or conceived. Yet only a little more than a hundred years ago women were first entering the academic world alongside men. These were often middle class women whose primary interactions with men had been through courtship and marriage. It was questioned whether women's intellectual ability and physical stamina were strong enough to persevere through the college experience. Scientists and physicians, writing for the general public, cited evidence that besides physical distinctions between the sexes, there were also intellectual and emotional differences. …
Electrostatically Paired Porphyrin And Phthalocyanine: Equilibria And Electrochemical Oxidation, Libin Ho '91
Electrostatically Paired Porphyrin And Phthalocyanine: Equilibria And Electrochemical Oxidation, Libin Ho '91
Honors Projects
A synthetic model system for the special pair in the photosynthetic reaction center of bacteria has been prepared from electrostatically paired porphyrin and phthalocyanine molecules. Use of rigorously dry propylene carbonate as the solvent allowed complex fonnation to occur between tetra-(N-methyl-4-pyridyl)porphyrin hexafluorophosphate (H2TMPyP(PF6)4) and tetraphenylphosphonium tetrasulfatophthalocyanine (Ph4P)4H2TSPc molecules. The stoichiometry of the complex was determined to be 1:1 by Job's method and the pair formation constant K1 was estimated to be 1x108.T he dependence of K1 on ionic strength was studied at various concentrations of tetra-n-butylammonium tetrafluoroborate BU4NBF4. With increasing ionic strength K1 decreases as expected according to the Debye-Huckellimiting …
Fourier Transform Infrared (Ftir) Spectroscopy Analysis Of Combustion Aerosol, Gary Jacquin
Fourier Transform Infrared (Ftir) Spectroscopy Analysis Of Combustion Aerosol, Gary Jacquin
Opportunities for Undergraduate Research Experience Program (OURE)
In conjunction with my co-op program at McDonnell-Douglas, my current OURE project is the analysis of combustion aerosols using Fourier Transform Infrared (FTIR) Spectroscopy. Aerosol science is a very important field as it is concerned with atmospheric chemistry, atmospheric physics, climate, public health, and environmental issues.
In the Cloud and Aerosol Sciences Laboratory (CASL) at UMR, combustion aerosols are generated by an in-house designed torch or burner. The fuels, JP4 and JP5, are provided by McDonnell-Douglas. Some other commercial fuels are also used. The primary objective of my OURE project was to generate and collect combustion aerosols for chemical analysis. …
Model Calculational Approach To The Conformation Of Adsorbed Polypeptide Fragments, Timothy J. Mckeon
Model Calculational Approach To The Conformation Of Adsorbed Polypeptide Fragments, Timothy J. Mckeon
Opportunities for Undergraduate Research Experience Program (OURE)
The focus of the paper is to examine possible conformational changes of peptides when placed in the presence of a poly-synthetic material. A major concern in the pharmaceutical industry is the loss of potency of polypeptide drug products during processing, packaging and storage. An example of this is polymer syringes being used in place of glass ones. The effect is that some protien-derived products experience structural changes due to contact with the polymer. This is otherwise known as surface denaturation. In order to understand the energetics of interfacial polypeptide systems, a calculational approach was used via the program Alchemy. The …
Analytical Modeling And Simulation For Investigation Of A Digital Gas Filter Correlation Radiometer, Catherine P. Mcgowan
Analytical Modeling And Simulation For Investigation Of A Digital Gas Filter Correlation Radiometer, Catherine P. Mcgowan
Electrical & Computer Engineering Theses & Dissertations
This thesis investigates a digital gas filter correlation radiometer called the Tropospheric Radiometer for Atmospheric Chemistry and Environmental Research (TRACER), which will be used to remotely measure carbon monoxide at three levels in the troposphere. The nadir-viewing radiometer measures the differential absorption of radiation through the atmosphere at 4.67@m and 2.33pm wavelengths. This thesis develops an analytical model of the TRACER measurement process to evaluate the effect of varying certain system parameters on the measurement. The independent sampling criterion and the response of linear systems to random signals are explained. A parametric simulation model is also developed to evaluate the …
An Assessment Of The Accuracy Of Semi-Empirical Quantum Chemistry Calculations Of The Mechanical Properties Of Polymers, James R. Shoemaker
An Assessment Of The Accuracy Of Semi-Empirical Quantum Chemistry Calculations Of The Mechanical Properties Of Polymers, James R. Shoemaker
Theses and Dissertations
The ultimate mechanical properties of polymers, assuming perfect morphology, will be limited by the mechanical properties of a single, ideal polymer chain. Previous calculations of polymer chain moduli using semi- empirical (SE) quantum chemistry methods have resulted in modulus values much higher than experimentally measured. This study investigated the error in the calculated inherent to the method of calculation by comparing SE results for C-C bond potentials in two well characterized polymers, polyethylene and polydiacetylene. It was found that the SE calculation systematically overpredicted bond stiffness in these polymers by approximately 25% to 30%. This is the upper limit on …
Evaluation Of D-Amino Acid Levels In Human Urine And In Commercial L-Amino Acid Samples, Daniel W. Armstrong, J. D. Duncan, S. C. Lee
Evaluation Of D-Amino Acid Levels In Human Urine And In Commercial L-Amino Acid Samples, Daniel W. Armstrong, J. D. Duncan, S. C. Lee
Chemistry Faculty Research & Creative Works
Detectable levels of four free D-amino acids (phenylalanine, tyrosine, tryptophan and leucine) were found in human urine. This was accomplished using a liquid chromatographic coupled column (i.e., achiral-chiral) method that was developed for the rapid and sensitive analysis of these compounds. The technique was tested on a series of commercial L-amino acids. Care was taken to minimize racemization. Trace to percent levels of contaminating D-enantiomers were found in all commercial samples. In urine the D-amino acids ranged from several hundredths of a percent up to percent levels of the corresponding excreted natural L-amino acids. There were no apparent correlations between …