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Articles 1741 - 1770 of 2634
Full-Text Articles in Physical Sciences and Mathematics
The Design And Construction Of Microprocessor-Computer Controlled Rapid Scanning Fiberoptic Spectrophotometer, Kathleen Marie Tobin
The Design And Construction Of Microprocessor-Computer Controlled Rapid Scanning Fiberoptic Spectrophotometer, Kathleen Marie Tobin
Masters Theses
Conventional spectrophometers require the transfer of a sample to a cuvette for obtaining spectra. The measurement of absorbance in situ can be accomplished using a fiber optic probe which can be placed directly in the sample. The fiber optic probe also minimizes environmental factors such as thermal or vibrational which may affect the absorbing species. A rapid scanning speed allows for essentially simultaneous wavelength monitoring.
The effect of coupling a rapid scanning spectrophotometer with a fiber optic probe provides for an extremely versatile system. When used in comjunction with a microprocessor or computer, this approach offers advantages such as data …
Direct Memory Acquisition Of Fast Analog Signals, Syed Javaid Iqbal
Direct Memory Acquisition Of Fast Analog Signals, Syed Javaid Iqbal
Masters Theses
A fast data transfer computer circuit is developed using the direct memory acquisition (DMAC) technique. For this purpose Z-80 microcomputer ·chips, manufactured by Ziolog, were used. The direct memory acquisition circuitry was developed in several stages and required both hardware and software development. An erasable programmable read only memory (EPROM) programmer was built for reading and loading the system program. The design, construction, and testing of the DMAC system are discussed in detail and an example of the use of this system for collecting data is given.
Subsurface Stratigrapy And Sedimentologic Control On The Productive Middle Devonian Age Richfield Member Of The Lucas Formation In The Michigan Basin, Sukru Nail Apak
Subsurface Stratigrapy And Sedimentologic Control On The Productive Middle Devonian Age Richfield Member Of The Lucas Formation In The Michigan Basin, Sukru Nail Apak
Masters Theses
The depositional system of the Middle Devonian Richfield Member of Lucas Formation in the Michigan Basin was delineated using well logs, cores, drillers' records, and the literature. The Richfield Member was deposited in Sabkha and lagoonal environments characterized by cycles of anhydrite, dolomite, and limestone. Seven significant productive dolomitic zones, interbedded with anhydrite and limestone can be correlated throughout the study area. These zones change laterally to anhydrite towards the west flank and to dense limestone towards the east flank of the basin. Post-depositional diagenetic history of the Richfield was established with the aid of scanning electron microscopy and electron …
A Study Of Integral Equations For Computing Radial Distribution Functions, Zainuriah Hassan
A Study Of Integral Equations For Computing Radial Distribution Functions, Zainuriah Hassan
Masters Theses
Integral equation T (a two parameter equation of the Ornstein-Zernike form) is studied for computing the radial distribution functions of simple classical fluids interacting pairwise according to the Lennard-Jones 6-12 potential function. Numerical calculations are done on a computer for the system in the gas and liquid phases. At a high temperature, equation T results are found to agree very well with equation C when the parameters are chosen in a similar way. At a temperature slightly above the critical temperature, results from other sources over a wide density range. In equation T, by varying two of the parameters, the …
A Seismic Study Of An Impact Feature In Cass County, Michigan, Mancheol Suh
A Seismic Study Of An Impact Feature In Cass County, Michigan, Mancheol Suh
Masters Theses
A geophysical investigation, including a seismic study, of the subsurface structure of the Calvin-28 oil field, Cass County, Michigan, indicates that the structure's origin may be related to an impact event. The structural closures in the time structure maps and drilling results both show a central uplift. The fault system in the Trempealeau Formation shows a structure similar to other proven astroblemes. Undisturbed layers just beneath the central uplift also provide evidence of an impact structure. The result of mathematical modeling of the central uplift under the assumption that the structure is an impact structure corresponds well with the drilling …
The Survival Of Mesophilic And Thermophilic Bacteria Subjected To Uv Irradiation, Sajida A. Shaikh
The Survival Of Mesophilic And Thermophilic Bacteria Subjected To Uv Irradiation, Sajida A. Shaikh
Masters Theses
Survival curves were determined for the mesophile, Bacillus licheniformis and the thermophile, Bacillus stearothermophilus after subjecting the cells to ultraviolet irradiation. Cells were grown at 37°C for the mesophile and at 55°C for the thermophile.
At low UV exposure times, the thermophile was more resistant to UV irradiation (had a better survival rate) than was the case for the mesophile. At higher exposure times, the situation was reversed, the mesophile having a greater survival rate than the thermophile.
The effect of changes in the temperature during irradiation was also determined. Thermophiles were greatly affected by changes in temperature while the …
A Practical Application To Data Consistency Validation Using Finite State Automata, Michael Lee Richardson
A Practical Application To Data Consistency Validation Using Finite State Automata, Michael Lee Richardson
Masters Theses
The data which are input to a complex information system must often be verified for both syntactic and semantic consistency. The syntactic consistency can be enforced in a straightforward manner during the data entry process. The semantic inconsistencies can be more difficult to discover. A general approach, using finite state automata, is demonstrated here as applied to enforce consistency on client questionnaire responses in a large information system. This approach is developed using those software engineering standards are outlined and justified in this research. A discussion of semantic inconsistencies which require more sophisticated techniques is included.
A Gravity Investigation Of Mountain Flank Thrusting And Normal Faulting, Madison And Tobacco Root Ranges, Montana, Stephen Thomas Wigger
A Gravity Investigation Of Mountain Flank Thrusting And Normal Faulting, Madison And Tobacco Root Ranges, Montana, Stephen Thomas Wigger
Masters Theses
Gravity modeling of west-dipping, Laramide mountain flank thrusts which involve Archean metamorphic rocks in the western Tobacco Root and northern Madison Ranges supports the idea that these thrusts are gently dipping.
The thrusts provided a favorable location for normal faulting during Neogene extension. The Neogene faults on the eastern portions of the Madison and Jefferson Basins are interpreted to be listric, and merge with the Laramide thrusts. Basin development occurred along a series of such faults, which dropped hanging wall blocks of the thrust sheets to progressively greater depths. The maximum depth of the Madison basin, near Ennis, was found …
Fluvial, Tidal And Storm Sedimentation In The Chilhowee Group (Lower Cambrian), Northeastern Tennessee, Mary R. Cudzil
Fluvial, Tidal And Storm Sedimentation In The Chilhowee Group (Lower Cambrian), Northeastern Tennessee, Mary R. Cudzil
Masters Theses
The Lower Cambrian Chilhowee Group of northeastern Tennessee consists of the Unicoi, Hampton and Erwin Formations and is divided into four facies. Facies G occurs only within the lower 200 m of measured section (the Unicoi Formation) and consists of fine-grained to pebbly quartz wacke with rare thin beds of laminated siltstone. Subfacies Gh consist of low-angle to horizontally laminated, fine-grained sandstone with laminae and lenses of granules and pebbles. Subfacies Gh represents upper flow-regime, overbank deposition within a braided stream system that was proximal to a coastline. Subfacies Gmr consists of medium-scale, planar-tabular cross-stratified conglomerate in which megaripple bedforms …
Construction And Testing Of A New Atomic Physics Beam Line At The Western Michigan University Accelerator Laboratory, William Andrew Hollerman
Construction And Testing Of A New Atomic Physics Beam Line At The Western Michigan University Accelerator Laboratory, William Andrew Hollerman
Masters Theses
A new beam line containing a differentially-pumped gas cell and charge state analyzing magnet was constructed for the purpose of measuring a wide variety of atomic inner-shell processes, such as excitation, ionization, and charge transfer. The completed system will be able to measure these individual atomic processes using coincidence techniques. Initial testing of the beam line was performed using 40MeV S+7+Ar collisions to determine the effect of the collimating slit size on the measured x-ray cross sections. These measurements showed that the slip size on the measured x-ray cross sections. These measurements showed that the slit size affects …
The Impeachment And Trial Of Secretary Of War William Worth Belknap, Duane Edward Holthof
The Impeachment And Trial Of Secretary Of War William Worth Belknap, Duane Edward Holthof
Masters Theses
The purpose of this thesis is to give an account of the events which lead to the resignation of Secretary of War William Worth Belknap in 1876, to examine the circumstances surrounding his impeachment, and to study the testimony in his Senate trial.
Although Belknap was not convicted on charges of accepting bribes, most of those senators who voted to acquit him did so on the technical ground that the Senate lacked the jurisdiction to try a private citizen. The evidence in the case clearly indicated Belknap's involvement, and there seems little doubt that if Belknap did not know what …
The Pauli Operator Correction In The Effective Λn Interaction, Jaleh Owliaei
The Pauli Operator Correction In The Effective Λn Interaction, Jaleh Owliaei
Masters Theses
Hypernuclear structure calculations performed for 6ΛLi, 7ΛLi, and 16Λ0 have reproduced the 1Λ=1 levels inferred from the recent (k, Π) reactions. However the 1Λ=0, groundstate of 16Λ0 is overbound by 6 MeV in these calculations, indicating a density dependence in the effective ΛN interaction in the interior of the heavier system. In this work corrections to the 16Λ0 effective interaction are introduced in terms of a Brueckner-Goldstone G-matrix with a modified Pauli operator. The G-matrix of 16Λ0 derived from that of 6ΛLi …
Resonant Electron Transfer And K-Shell Excitation Of Lithiumlike Projectiles In Collisions With Neutral Gas Targets, Carollyn Sloan Oglesby
Resonant Electron Transfer And K-Shell Excitation Of Lithiumlike Projectiles In Collisions With Neutral Gas Targets, Carollyn Sloan Oglesby
Masters Theses
No abstract provided.
A 73.8 Mhz Radio Interferometer Telescope For Intense Celestial Sources, William Charles Millar
A 73.8 Mhz Radio Interferometer Telescope For Intense Celestial Sources, William Charles Millar
Masters Theses
A 73.8 MHz radio interferometer telescope was built, based on a published design. Although the design was proven, the telescope has thus far given no results on celestial sources. The electronics has been proven to be operational by testing them with hand-held dipole radio sources. Here, the electronics is evaluated with a discussion of possible reasons for the failure of the telescope in overall operation.
Reactivity Of Some Nitrogen-Containing Compounds At Supercritical Water Conditions, David M. Tiffany
Reactivity Of Some Nitrogen-Containing Compounds At Supercritical Water Conditions, David M. Tiffany
Masters Theses
The use of water at cuperctirical conditions to remove nitrogen from several nitrogen-containing compounds was studied with the purpose of exploring the use of supercritical water as a method of removing nitrogen from the extraction products of coal. Quinoline and isoquinolone were the primary model compounds used with benzonitrile and carbazole also being examined briefly. Reaction conditions varied in temperature (350-500°C), pressure (3500-5200 psi), and water density (0.170-.0.426g/cc). The major products formed by isoquinoline were benzene, toluene, ethylbenzene, and o-xylene as well as nonvolatile tar and char. Quinoline produced aniline and toluidine in addition to those obtained from isoquinoline. Most …
Late-Quaternary Vegetational History At Jackson Pond Larue County, Kentucky, Gary R. Wilkins
Late-Quaternary Vegetational History At Jackson Pond Larue County, Kentucky, Gary R. Wilkins
Masters Theses
A 6.2 meter core of lacustrine sediment from Jackson Pond, Larue County, Kentucky represents the first continuous sequence from Kentucky permitting the vegetational reconstruction for the full-glacial through late-Holocene intervals. Jackson Pond is a spring-fed pond situated within a karst-collapse basin underlain by Ste. Genevieve and St. Louis limestone of Mississippian age. The site is located at 37°27'N, 85°30'W, 190 km south of the full-glacial limit of the Laurentide Ice Sheet. Six sediment samples submitted for radiocarbon analysis provide an absolute chronology for the site for the last 20,460 years.
From 20,460 yr B.P. to 20,330 …
Thermodynamics Of Ion Association In Aqueous Fluoride Solutions. Determination Of Stability Constants For (Naf), (Mgf)+ And (Caf)+ Ion Pairs, Waldo Zamorano-Santander
Thermodynamics Of Ion Association In Aqueous Fluoride Solutions. Determination Of Stability Constants For (Naf), (Mgf)+ And (Caf)+ Ion Pairs, Waldo Zamorano-Santander
Masters Theses
Stoichiometric ion-association constants were determined at several ionic strengths for (NaF) over the temperature range 15-40°C and for (MgF)+ and (CaF)+ over the temperature range 25-45°C using fluoride ion selective electrode measurements.
Thermodynamic association constants, K°, were obtained through extrapolation of the stoichiometric values to infinite dilution. Values of K° for (NaF) are 1.70, 2.16 and 2.54 at 15, 25 and 40°C, respectively. The K° values for (MgF)+ are 73.4, 88.0 and 98.2, and for (CaF)+ are 13.7, 17.5 and 21.9 at 25, 35 and 45°C., respectively.
The stoichiometric association constants for (NaF) can be reproduced …
Bimetallic Complexes Of Tungsten And Mercury, Zakariah Abdullah
Bimetallic Complexes Of Tungsten And Mercury, Zakariah Abdullah
Masters Theses
A tungsten-mercury bimetallic complex [(CO)4W(PPh2CH2CH2PPh2)2HgCl2]n has been synthesized from the reaction of trans-(CO)4W(η1-PPh2CH2CH2PPh2)2 and HgCl2. The value of n has not been determined due to the insolubility of the complex. The anologous reaction with HgI2 gave an insoluble, uncharacterizable complex, which best corresponds to (CO)4W(PPh2CH2CH2PPh2)2Hg2I4.
The geometry about tungsten in [(CO)4 …
Bimetallic Tungsten Carbonyl Complexes, Jin-Guu Wang
Bimetallic Tungsten Carbonyl Complexes, Jin-Guu Wang
Masters Theses
Two heterobimetallic complexes, [(CO)4W(PPh2CH2CH2-PPh2)2MCl2]n ( M = Pd or Pt ), were prepared from the reaction of trans-W(CO)4(ŋ1-PPh2CH2CH2PPh2) 2 with M(COD)Cl2 (COD = cyclooctadiene). A trans arrangement about tungsten was found for both the palladium and platinum complexes. The square planar palladium center was shown to have a trans geometry in solution while a cis arrangement for the platinum moiety was observed. Far infrared studies indicated a mixture of cis and trans …
Industrial Simulation With Animation, Edward T. Hammerand
Industrial Simulation With Animation, Edward T. Hammerand
Masters Theses
"This thesis examines and evaluates the new simulation language PCModel. Prior to the arrival of PCModel, simulation via computer typically resulted in pages of statistics compiled over the duration of the simulation. PCModel's approach is to simulate the model on the display before the user in real time. Additionally, user interaction is supported to allow changes to be made throughout the simulation run.
The evaluation of PCModel is accomplished through inspection of a pair of examples already simulated in a conventional simulation language. The examples show the relative strong and weak points of the language, as well as demonstrating how …
Carbonate Facies Of The Kimmswick Limestone (Trenton/Galena) In Southwestern Illinois : Their Relations As Oil Reservoirs And Traps, Gregory A. Crews
Carbonate Facies Of The Kimmswick Limestone (Trenton/Galena) In Southwestern Illinois : Their Relations As Oil Reservoirs And Traps, Gregory A. Crews
Masters Theses
"Four potentially productive oil horizons have been identified in the Kimmswick Limestone (Trenton/Galena), Ordovician of southwestern Illinois. Four non-porous caprock zones and four porous horizons were identified and informally named after corresponding members of the Dunleith Formation (Illinois State Geological Survey classification). The porous horizons generally consist of coarse-grained, fossiliferous limestone, which is overlain by finer grained, spar-cemented, impermeable limestone.
In order of production potential, the horizons are the upper Moredock, lower Moredock, Beecher-St. James (lowermost stratigraphic unit), and New London (uppermost stratigraphic unit). Porosity in the upper Moredock horizon is relatively consistent throughout the study area, as determined by …
Heterocyclic Syntheses Utilizing Aryl Cyanates, Joseph Eugene Drumm
Heterocyclic Syntheses Utilizing Aryl Cyanates, Joseph Eugene Drumm
Masters Theses
No abstract provided.
Uranium-Lead Zircon Ages And Crustal Contamination Of The Northeastern Idaho Batholith, James J. Dexter
Uranium-Lead Zircon Ages And Crustal Contamination Of The Northeastern Idaho Batholith, James J. Dexter
Masters Theses
The magmas which formed the northeastern Idaho batholith were contaminated with, or derived from, old crustal material as evidenced, from previous studies, by high whole-rock 87Sr/86Sr ratios, relatively high 207Pb/206Pb ages, and Archean to Proterozoic upper intercept ages for batholithic zircons.
The old zircon component has been identified in this study by separating zircons into fractions based on size and morphology. Pb/U isotopic ratios are distributed on a chord with a lower concordia intercept intrusive age of 73.6+6 m.y. Zircons from a batholithic sample located one kilometer inward from the contact were separated according …
Hydrogeologic And Geochemical Factors Influencing The Impact Of A Chromium-Arsenic-Copper Wastewater Discharge On A Glacial Outwash Aquifer, Michael J. Gallagher
Hydrogeologic And Geochemical Factors Influencing The Impact Of A Chromium-Arsenic-Copper Wastewater Discharge On A Glacial Outwash Aquifer, Michael J. Gallagher
Masters Theses
A discharge of chromium-arsenic-copper laden wastewater occurred periodically from 1970 to 1980 at a wood preserving company located in southwestern Kalamazoo County, Michigan. As a result of this discharge, soils at the company site became contaminated with chromium, arsenic, and copper, and a local glacial outwash aquifer became contaminated with hexavalent chromium.
Soil samples collected from the discharge site were analyzed for clay-silt-sand-gravel content, organic matter, pH, clay mineralogy, and chromium, arsenic, copper, iron, and manganese content. Background soil samples were analyzed for most of the above catagories. Pearson r coefficients of correlation were calculated to determine the correlation of …
Resolution Algorithms In A Parallel Processing Environment, Paula Beth Brandman Hencken
Resolution Algorithms In A Parallel Processing Environment, Paula Beth Brandman Hencken
Masters Theses
An ever increasing number of processors are becoming available to the multiprocessor user. For faster response and efficient utilization of parallel processing systems it is necessary to develop parallel algorithms to solve a single problem.
This paper evaluates the complexity of resolution algorithms run in a parallel processing environment. An overview of parallel processing is presented along with a discussion of general resolution and resolution-refutation systems. An analysis of the complexity required by different control strategies to perform resolution programing is presented using both uniprocessor and multiprocessor systems.
The Application Of Multiderivative Infrared Spectroscopy To Iodine Number Determination, Jeffrey C. Lowry
The Application Of Multiderivative Infrared Spectroscopy To Iodine Number Determination, Jeffrey C. Lowry
Masters Theses
The Food and Drug Administration requires the disclosure of total unsaturation of commercial products as an indication of nutritional value. This unsaturation is a guide to the expected stability of food additives, such as edible oils and foods in which they are used. Unsaturation is typically evaluated as an iodine number, calculated for these additives based on their consumption of iodine through addition across the carbon-carbon double bonds. This titration method can typically take 45 minutes.
The investigation presented develops an alternative method for determining iodine numbers of some common oils using a computerized infrared spectophotometer. The analysis time, as …
Kinetics Of The Formation Of The Nickel(Ii) Complex With N, N' -Dimethylethylenediaminediacetic Acid And The Metal Exchange Reaction Between N,N'-Dimethylethylenediaminediacetatonickel(Ii) And Copper(Ii), Roger A. Karel
Masters Theses
The kinetics of the reaction of aquonickel (II) ion with N'N'-dimethlethylenediaminediacetic acid has been studied at 25°C and 0.1M iconic strength over a pH range of 6.0 to 9.3 using stopped-flow techniques. Formation reactions in all cases were first-order in Ni (II) and in ligand. The formation rate constant for the protonated and unprotonated species were evaluated and compared to their theoretical value. The rate-determining step is shown to be ring closure. A comparison of this system with other studies involving complexation of nickel (II) confirm the magnitude of the internal conjugate base effect and also shows a correlation between …
The Kinetics Of The Metal Exchange Reaction Between N-(2-Hydroxyethyl) Iminodiacetatonickelate (Il) And Copper(Ii), Craig R. Weed
The Kinetics Of The Metal Exchange Reaction Between N-(2-Hydroxyethyl) Iminodiacetatonickelate (Il) And Copper(Ii), Craig R. Weed
Masters Theses
The reaction between copper(II) and N -(2-hydroxyethyl)iminodiacetatonickelate( II) (NiHEIDA) was studied between pH 4.0 and 5.6 over a 70 fold variation in copper concentration at an ionic strength of 1.25 and a temperature of 25° C. The reaction order in both NiHEIDA and Cu(U) is first. The reaction rate is pH sensitive and a hydrogen dependent pathway as w ell as copper dependent and copper and hydrogen independent pathways were found.
Evidence is given for a stepwise mechanism for the unwrapping of HEIDA from its nickel complex, follow ed by copper attack to give a dinuclear intermediate, which then breaks …
The Depositional History Of The Point Pleasant Member Of The Cynthiana Formation In Northern Kentucky, Gary J. Stefaniak
The Depositional History Of The Point Pleasant Member Of The Cynthiana Formation In Northern Kentucky, Gary J. Stefaniak
Masters Theses
Bioclastic limestones, siltstones, and shales of the Point Pleasant Member were deposited in a shallow marine environment immediately below normal effective wave base. High-energy conditions produced by storms lowered the effective wave base and stirred the bottom sediments and redistributed them into bedforms. The different types of contacts, distribution of the faunal groups, and fabrics permit inferences regarding energy levels and assignment of samples to a mode of deposition. Vertical and lateral trends were then deduced. High-energy conditions are believed to have occurred during Early and Late Point Pleasant time, whereas, low-energy conditions prevailed during deposition of the middle Point …
A Study Of Integral Equations For Computing Radial Distribution Functions, Robert C. Scherzer
A Study Of Integral Equations For Computing Radial Distribution Functions, Robert C. Scherzer
Masters Theses
The use of integral equations to find radial distribution functions for computing thermodynamic properties is examined. The system considered is a simple classical fluid with interactions according to the Lennard-Jones (6-12) pair potential function. Two parametric integral equations (C and T) are studied in detail. Derivation of equation T and a power series solution are given. Computer solutions at several different temperatures, densities, and parameter values are obtained. Comparisons are made betv/een these results and results from integral equation N, PY, and HNC, and results from Monte Carlo, molecular dynamics, and power series methods. Equations C and N are found …