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Articles 1531 - 1560 of 2077
Full-Text Articles in Physical Sciences and Mathematics
Multispectral Analysis Of Erts Imagery By Color Enhancement, John F. Peters
Multispectral Analysis Of Erts Imagery By Color Enhancement, John F. Peters
Masters Theses
"The Earth Resources Technology Satellite (ERTS) program has supplied the scientist with high resolution multispectral imagery of a large portion or the earth. Photographic and electronic methods of image enhancement are not universally available to those who might profit from such endeavors.
Diazo products were found to be satisfactory for creation of false color enhancement of ERTS multispectral data. The purpose of the enhancement was to make the Diazochrome composite comparable to more sophisticated methods for the purpose of interpretation. The basis of the enhancement was the standard false color infrared composite, with negative and positive Diazochrome masks to enhance …
The Consideration Of Some Aspects Of Two Methods Used To Study Ion Association, Richard Karl Gard
The Consideration Of Some Aspects Of Two Methods Used To Study Ion Association, Richard Karl Gard
Masters Theses
An investigation was made into the possibility of determining thermodynamic ion association equilibrium constants for salts important in the study of seawater using spectrophotometry and ion selective electrodes. Calcium sulfate was used as the test salt. The success of the spectrophotometric method was found to depend upon the choice of a suitable indicator and refinement of the proper instrumental techniques. The indicators investigated were 1-(2'-hydroxy-1'-benzeneazo)-2-hydroxynaphthalene, 1-(2'-hydroxy-5'-chloro-1'-benzeneazo)-2-hydroxynaphthalene, and ammonium purpurate (murexide). Ammonium purpurate was found to be the most suitable indicator. Spectra of these three indicators and their calcium complexes at pH 10 are included in the paper. The ion selective …
A Study Of Organochlorine Insecticides In Freshwater Crayfish -- Analytical Problems And Biomonitoring Survey, Robert C. Vanderjack
A Study Of Organochlorine Insecticides In Freshwater Crayfish -- Analytical Problems And Biomonitoring Survey, Robert C. Vanderjack
Masters Theses
Crayfish were collected from 3 sites on Polecat Creek, Coles County, Illinois in early spring, early summer, and late summer of 1972. Pesticides were extracted from the crayfish tissue in a one step procedure utilizing a Florisil elution column. Analysis was by electron capture gas chromatography. Pesticide residues in the nannogram range were analyzed and background contamination was an important consideration. Sources of background contamination were investigated and teflon stopcocks, Florisil, and residues on “cleaned” glassware were found to be major contamination sources. Distilled water used in flushing glassware should also be considered a potential contamination source.
Aldrin, dieldrin, and …
Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen
Structure And Chemical Composition Of The Otoliths Of Cyprinus Carpio, Larry Paul Coen
Masters Theses
"The need for the study of microfossils such as foraminifera, conodonts, and otoliths as stratigraphic tools has been well established. However, disarticulated parts such as otoliths and conodonts cannot be effectively used unless they can be recognized. Otoliths, although somewhat unrecognized in the geological record, are far more abundant than articulated skeletons (Frizzell, 1965, p. 86). Therefore, much investigation is being conducted to reveal the origin, function, morphology, and usefulness of the otoliths of fishes.
In this investigation, the asteriscus, well developed only in Ostariophysins (of which the carp is a member), is studied for morphology. New tentative terms are …
Desorption Of Phosphorus From Si (111) Surfaces, Cesar Michel Magnin
Desorption Of Phosphorus From Si (111) Surfaces, Cesar Michel Magnin
Masters Theses
"Auger electron spectroscopy and mass analysis are used as complementary methods in evaluating desorption kinetics. For phosphorus on silicon, the order of desorption and activation energies of desorption are determined from continuously monitored phosphorus Auger electron signals during heating. These measurements indicate that diatomic phosphorus dissociates when adsorbed onto clean silicon. Mass spectrometer flash desorption spectra show that at least four distinct surface bonds are associated with the desorption of phosphorus. The dominant desorbed species is diatomic phosphorus at high coverage (> 0. 1 monolayer) and atomic phosphorus at low coverage (< 0.07 monolayer)"--Abstract, page ii.
Computer Investigation Of The Variation Of Conductivity With Concentration, Larry Macpeers Shadwick
Computer Investigation Of The Variation Of Conductivity With Concentration, Larry Macpeers Shadwick
Masters Theses
Computer programs were developed tor the conductance equations of R. M. Fuoss and L. Onsager as well as for the conductance equations of T. J. Murphy and E. G. D. Cohen. These programs were used to calculate values from selected conductance measurements. The resulting values were compared with values produced by other computer programs using the equations of Fuoss and Onsager as well as the equations of E. Pitts. The comparisons demonstrated the equations of Murphy and Cohen to be the equal of or superior to the other equations for the majority of cases. The equations of Pitta were superior …
The Conductance Of Some Polyvalent Electrolytes, Jack Lee Worthington
The Conductance Of Some Polyvalent Electrolytes, Jack Lee Worthington
Masters Theses
A new compound, 1,3,5-triphenylbenzene-4' ,4",4"'-trisulfonic acid, was synthesized by treating triphenylbenzene in 1,2-dichloroethane with chlorosulfonic acid. The reaction appears to be quantitative. Conductance measurements were then made on the sodium, potassium, and lanthanum salts of this new acid and of 1,3,5-benzenetrisulfonic acid.
The choice of these acids was based on two factors: 1) the desire to prepare a 3-3 symmetrical unassociated electrolyte which would allow the determination of a more reliable equivalent ionic conductance value for La3+ and 2) an interest in using the Murphy-Cohen equation to determine solute parameters such as association constants if association is present.
Conductance …
The Fauna And Paleoecology Of The Charleston Quarry Shale, James Karl Gilliam
The Fauna And Paleoecology Of The Charleston Quarry Shale, James Karl Gilliam
Masters Theses
The fauna and paleoecology of a late-Pennsylvanian shale contained in the Livingston Limestone of eastern Illinois is here defined. The name, Charleston quarry shale, is informally used for this shale in the area of the Charleston Stone Company quarry, northeast of Charleston, Illinois (SEC. 32, T. 13N., R. 10E., Coles Co.).
The fauna consists mostly of bryozoans, brachiopods and crinoids distributed throughout three distinct zones in the Charleston quarry shale. This fauna inhabited an offshore quiet bottom area in a shallow, warm, marine epicontinental sea which covered the area in the late-Pennsylvanian geologic period. The depth of water above the …
A Study Of The Ability Of Surface Active Materials To Increase The Evaporation Rates Of Small, Freely Falling Water Drops, David Alan Sierawski
A Study Of The Ability Of Surface Active Materials To Increase The Evaporation Rates Of Small, Freely Falling Water Drops, David Alan Sierawski
Masters Theses
"The evaporation rate at 30°C of water droplets partially covered by surface active materials (SAM) were determined. While two of the SAM were studied at a single dew point depression (ΔTDP), seven others were examined over a range of ΔTDP values. It was found, by comparison with pure water drops under identical conditions, that SAM increases the evaporation rate as compared to the rate of an uncontaminated drop. The lack of effect of the hydrophobic chain length and the possible effect of the hydrophilic group on this phenomenon are discussed. The explanation proposed is that at 30°C …
The Isolation And Purification Of A Fluorescent Compound From Pseudomonas, Thomas M. Davey
The Isolation And Purification Of A Fluorescent Compound From Pseudomonas, Thomas M. Davey
Masters Theses
Fluorescence in certain land snails has been found to arise from a bacteria carried by the snails. The bacteria, a genus of Pseudomonas, produce a pigment complex in iron-deficient media. The pigment complex consists of both fluorescent and non-fluorescent pigments. One of the fluorescent compounds was isolated and purified by paper chromatography using several different solvent systems.
Absorption and fluorescent spectra of the compound at a number of pH values were measured and the changes with pH of both the intensity and the color of the fluorescence were observed. The purified compound was ninhydrin negative but after acid hydrolysis …
Mechanistic Studies Of Cobalt Super Nucleophiles, Audrey Yeh Ku
Mechanistic Studies Of Cobalt Super Nucleophiles, Audrey Yeh Ku
Masters Theses
A study was initiated on the hypothesis, by Ugi and co-workers, that cyclopropyl, cyclobutyl, and cyclopentyl electrophiles might undergo nucleophilic substitution reactions with retention of configuration.
A simple, high yield synthesis of both cis and trans-2-phenylcyclopropyl chlorides from styrene and chloroform is described. Reaction of each of these alkylating agents with the very nucleophilic cobaloxime super-nucleophile ultimately gave peroxy compounds which appear to arise from insertion of oxygen into the carbon-cobalt bond.
Neither trans-2-phenylcyclopentyl tosylate nor trans-2-phenylcyclohexyl tosylate would alkylate low valent cobaloximes under standard conditions.
A partial synthesis of the 2-phenylcyclobutyl tosylate is described along with suggestions for future …
Numerical Study Of Slow Motion Of A Smoke Filament, Tapan Sen
Numerical Study Of Slow Motion Of A Smoke Filament, Tapan Sen
Masters Theses
No abstract provided.
Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins
Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins
Masters Theses
"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …
Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis
Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis
Masters Theses
"ESR has been used to study the formation of an amorphous layer in silicon by ion implantation. The room temperature implants were done at 20 keV with low dose rates. The critical dose was determined as a function of ion mass for six different ion species. Our experimental heavy ion results agree with those found by other ESR investigators at higher energy, but are not the same for light ions. However, our light and heavy ion results agree with electron microscope measurements for low energy implants. An energy-independent model for the formation of amorphous silicon by ion implantation has …
The Analysis Of Three Narrow Resonances Observed In Protons On Oxygen-16, Benjamin Y. J. Tan
The Analysis Of Three Narrow Resonances Observed In Protons On Oxygen-16, Benjamin Y. J. Tan
Masters Theses
No abstract provided.
The Design And Construction Of An Electron Lens For Use In A Low Energy Electron Diffraction System, Rodney S. Krieger
The Design And Construction Of An Electron Lens For Use In A Low Energy Electron Diffraction System, Rodney S. Krieger
Masters Theses
No abstract provided.
Hydrostatic Pressure Effects On The Epr Spectrum Of V2+: A1203 And Cr3+: A120, Charles J. Wilcox
Hydrostatic Pressure Effects On The Epr Spectrum Of V2+: A1203 And Cr3+: A120, Charles J. Wilcox
Masters Theses
No abstract provided.
On The Genus Of Hamiltonian Groups, Paul E. Himelwright
On The Genus Of Hamiltonian Groups, Paul E. Himelwright
Masters Theses
No abstract provided.
The Formation And Study Of Certain Bicyclic Enolate Monoanions And Dianions, Ernest William Crowe
The Formation And Study Of Certain Bicyclic Enolate Monoanions And Dianions, Ernest William Crowe
Masters Theses
No abstract provided.
Calculations Of Nuclear Structure Using Isospin Formalism, Roger A. Cook
Calculations Of Nuclear Structure Using Isospin Formalism, Roger A. Cook
Masters Theses
No abstract provided.
The Dimetalation And Subsequent Functionalization Of 1,3-Dimethylnaphthalene By Means Of Amylsodium In The Presence Of Certain Tertiary Amines, Atilla Tuncay
Masters Theses
I. Introduction
It is well known that the hydrogen atoms of a methyl group directly attached to an aromatic system are sufficiently acidic to be abstracted by suitable bases to generate the corresponding α-anion.1,2 These monoanions have frequently served as suitable intermediates for the formation of a large variety of a-condensation products in good to excellent yields2 On the other hand, attempts to obtain α,α-dianions from various dimethylaromatic systems have met with limited success.2 Due to the lack of sufficiently strong bases, dimetalation products were obtained only in poor yields even at high temperatures and prolonged reaction …
Kinetics Of The Formation Of Nickel(Ii) Complexes With N,N’-Dibenzylethylenediamine And N,N’-Bis(2-Picolyl)Ethylenediamine, Zahid Amjad
Masters Theses
No abstract provided.
Sediment-Topography Relationships In The Inner Nearshore Zone, Southeastern Lake Michigan, Robert David Lopiccolo
Sediment-Topography Relationships In The Inner Nearshore Zone, Southeastern Lake Michigan, Robert David Lopiccolo
Masters Theses
No abstract provided.
The Relationship Between Degree Of Clay Dispersion And The Optical And Pore Properties Of Starch - Clay Coatings, Chinu S. Dalal
The Relationship Between Degree Of Clay Dispersion And The Optical And Pore Properties Of Starch - Clay Coatings, Chinu S. Dalal
Masters Theses
No abstract provided.
Kinetics Of Free Radical-Initiated Polymerization Of Α-Methylstyrene In The Region Of The Ceiling Temperature, Fred E. Huang
Kinetics Of Free Radical-Initiated Polymerization Of Α-Methylstyrene In The Region Of The Ceiling Temperature, Fred E. Huang
Masters Theses
No abstract provided.
Heats Of Combustion Of Alpha-Methylstyrene Oligomers, Dale Keith Humbert
Heats Of Combustion Of Alpha-Methylstyrene Oligomers, Dale Keith Humbert
Masters Theses
Introduction
The heat of polymerization (∆Hp) of α-methylstyrene (AMS) has been a source of study for many years. The structure of AMS is shown in Figure 1.
The first quantitative work was done by Roberts and Jessup.1 Their values were more positive than those theoretically calculated by Flory2 and compared with ∆Hp data of other systems. This was not totally unexpected and could be satisfactorily explained on the basis of steric hindrance and loss of resonance energy of conjugation. This steric hindrance arose from "head-to-tail" polymerization of the 1, 1-disubstituted ethylene structure.3 Their data …
Scattering Spin 1/2 Particles By Nuclei, Pui-Wah Cheng
Scattering Spin 1/2 Particles By Nuclei, Pui-Wah Cheng
Masters Theses
No abstract provided.
Development Of An Ultra High Shear Recording Viscometer, David C. Thornton
Development Of An Ultra High Shear Recording Viscometer, David C. Thornton
Masters Theses
No abstract provided.
Studies Of Neutron Capture Produced Rare Gas Isotopes In Rocks And Minerals Containing Chlorine, Selenium And Tellurium, David E. Sinclair
Studies Of Neutron Capture Produced Rare Gas Isotopes In Rocks And Minerals Containing Chlorine, Selenium And Tellurium, David E. Sinclair
Masters Theses
"Noble gas mass spectrometry was used to study rare nuclear processes in terrestrial rocks and minerals. An excess of 36Ar was detected in a chlorine-rich rock. The excess 36Ar has been produced in rocks near the earth's surface due to capture of cosmic-ray-produced neutrons on 35Cl. Measurement of 36Ar formed by the 35Cl(n, γ)36Cl(β-)36Ar process makes possible a new method for determining the surface residence time of chlorine-rich minerals
Excess 82Kr and excess 83Kr were detected in selenium-rich ores. The excess 82Kr results from double beta …
Equilibrium And Kinetic Study Of The Substitution Reactions Of Pentacarbonylaminetungsten (O) With Triphenylphosphine, William O. Bailey
Equilibrium And Kinetic Study Of The Substitution Reactions Of Pentacarbonylaminetungsten (O) With Triphenylphosphine, William O. Bailey
Masters Theses
A kinetic and equilibrium study of the reaction of triphenylphosphine (PPh3) with pentacarbonylaminetungsten (O) [(CO)5WNH2C6H5] has been reported previously. Equilibrium constants for the reaction (CO)5WNH2C6H5 + PPh3 = (CO)5W[P(C6H5)3] + C6H5NH2 in toluene were reported to be 17.1, 49.2 and 65.7 respectively. In addition, the entropy change (ΔS) for the reaction was found to be 86±5 cal mol-1 deg-1.
In this study the above reaction was …