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Doctoral Dissertations

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Articles 1741 - 1770 of 1882

Full-Text Articles in Physical Sciences and Mathematics

Homogeneous Nucleation Of Water Vapor In Inert Gas Atmospheres, Arthur Henry Biermann Jan 1971

Homogeneous Nucleation Of Water Vapor In Inert Gas Atmospheres, Arthur Henry Biermann

Doctoral Dissertations

"The homogeneous nucleation of water vapor in atmospheres of helium, neon, argon, krypton, and xenon was studied using an expansion type cloud chamber. A strong dependence of the nucleation rate on the particular inert carrier gas was observed. At present the only dependence upon the nature of the carrier gas included in classical nucleation theories is a small factor arising from kinetic considerations which is in the wrong direction to explain the observations. To explain the dependence of the rate on the nature of the carrier gas, a molecular cluster model is assumed allowing inert gas atoms to occupy the …


Absolute Cross Sections For Excitation Of Neon By Impact Of 20-180 Kev H , H₂ And He Ions, George William York Jan 1971

Absolute Cross Sections For Excitation Of Neon By Impact Of 20-180 Kev H , H₂ And He Ions, George William York

Doctoral Dissertations

"The technique of heavy-ion energy-loss spectrometry has been used to measure excitation cross sections for the (2p⁵)3s and (2p⁵)3p electronic configurations of Neon. The incident particles used were H⁺ , H⁺₂ and He⁺ at impact energies from 20-180 keV. The results are compared with previous optical measurements of the emission cross sections of lines from these levels as excited by H⁺ and He⁺ impact. Agreement is not good, either in shape or in absolute magnitude for excitation of the (2p⁵)3s configuration. However, agreement is surprisingly good for excitation of the (2p⁵)3p configuration. A curve fitting technique has been applied to …


Distribution Of Trace Elements In Olivines And Proxenes - An Experimental Study, Melvin Leroy Bird Jan 1971

Distribution Of Trace Elements In Olivines And Proxenes - An Experimental Study, Melvin Leroy Bird

Doctoral Dissertations

"Olivine, pyroxene,and spinel were crystallized in the ternary system anorthite-forsterite-silica to which trace amounts of the transition metal ions Cr³⁺, Fe²⁺, Mn²⁺, Co²⁺, Ni²⁺, and Cu²⁺ had been added. The resulting concentrations of the transition metal ions in the liquid and crystalline phases were determined using the electron microprobe. The results, given as free energies and partition functions, indicate the order of substitution of the dipositive ions in all crystals to be Ni²⁺, Co²⁺, Mn²⁺, Cu²⁺, and Fe²⁺ according to the predictions of crystal field theory. The ion Cr³⁺ substituted in greater or lesser quantities depending on the crystalline phase. …


Some Statistical Inferences For The Bivariate Exponential Distribution, Bruce Mohr Bemis Jan 1971

Some Statistical Inferences For The Bivariate Exponential Distribution, Bruce Mohr Bemis

Doctoral Dissertations

"The bivariate exponential distribution is neither absolutely continuous nor discrete due to the property that there is a positive probability that the two random variables may be equal. Basic properties of the distribution are presented as well as methods of parameter estimation including maximum likelihood. The distribution is shown to satisfy the usual regularity conditions in spite of its possession of a singularity. The maximum likelihood estimates are asymptotically efficient. Two other methods of estimation are compared with the maximum likelihood method in terms of efficiency. Tests of the hypothesis that two random variables each have independent exponential distributions versus …


Part A: Some Reactions Of Norbornene Oxide: Part B: Arylnorbornene Oxides, Thomas J. Gerteisen Dec 1970

Part A: Some Reactions Of Norbornene Oxide: Part B: Arylnorbornene Oxides, Thomas J. Gerteisen

Doctoral Dissertations

Part A: In this thesis research on the action of Grignard reagents with with norbornene oxide has been initiated and found to be of possible synthetic utility.

Part B: The structure of the product of the acid catalyzed dehydration of 2-p-anisylnorbornane-2, 3-cis-exo-diol in hydrochloric acid-tetrahy-drofuran has been reassigned. It was discovered, on the basis of further data, that the structure of the high melting solid was that of the dimer of the epoxide, a p-dioxane, rather than the epoxide itself. This change was proposed for many reasons. A near total nmr analysis of the compound …


Quantitative Spark-Source Mass Spectrometric Techniques For The Simultaneous Determination Of The Lanthanide And Actinide Elements In Microgram And Sub-Microgram Transuranium Samples, Joel Avery Carter Jun 1970

Quantitative Spark-Source Mass Spectrometric Techniques For The Simultaneous Determination Of The Lanthanide And Actinide Elements In Microgram And Sub-Microgram Transuranium Samples, Joel Avery Carter

Doctoral Dissertations

The work presented encompasses techniques developed for the analysis of certain rare earth and actinide elements in solutions containing highly radioactive transuranium elements. Advantage was taken of the high inherent resolution and sensitivity of the rf spark-source mass spectrometer in the development of qualitative and quantitative procedures where an analysis can be made on a total sample of <1 to 10 μg. Parameters for the Associated Electrical Industries' MS-702 spark-source mass spectrometer were adjusted so that mass-to-charge ratios in the range of 10 to 310 could be subjected to qualitative analysis. For quantitative assessment of impurities in a transuranium solution, relative sensitivity factors were established with respect to erbium, the internal standard, for rare earth elements and for thorium, uranium, neptunium, americium, curium, berkelium, and californium.

A special glove box was designed, fabricated, and used on the source end of the mass spectrometer so that samples of the transuranium elements could be run safely. Transuranium element with α-emitting radioactivity up to 1010 dpm were processed through the …


Investigation Into The Monotonic Magnetostriction And Magnetic Breakdown In Cadmium, James Milo Carter Jan 1970

Investigation Into The Monotonic Magnetostriction And Magnetic Breakdown In Cadmium, James Milo Carter

Doctoral Dissertations

"Observations of the monotonic magnetostriction of cadmium at 4.2 K and in fields of 65 kilogauss have been made. The angular dependence of an extremal point (Hm) in the monotonic magnetostriction is found to follow inverse cosine behavior. The magnitude of Hm (27 kG) for fields parallel to [0001] is in fair agreement with the onset of γ1/3 from the breakdown of the trifoliate orbit, γ. The range of observation of hm coincides with the reported range of the trifoliate orbit. A "klink" in the monotonic magnetostriction is demonstrated. The "klink" field, Hk, …


Absolute Excitation Cross Sections Of He⁺ In 20-100 Kev He⁺-He Collisions Using Energy-Loss Spectrometry, Donald Roy Schoonover Jan 1970

Absolute Excitation Cross Sections Of He⁺ In 20-100 Kev He⁺-He Collisions Using Energy-Loss Spectrometry, Donald Roy Schoonover

Doctoral Dissertations

"Application of positive-ion energy-loss spectrometry has been extended to include experimental determination of absolute excitation cross sections of ground state helium ions. Helium ion-atom collisions were studied for impact energies ranging between 20-100 keV, in 10 keV intervals. The data were taken with an apparatus resolution between 0.6-o.8 eV FWHM. Cross sections for transitions from ground state to the second and third principal quantum levels of the ion plotted as a function of impact energy were still rapidly increasing at 100 keV. The cross sections at this energy were 1.64(± 0.28) x 10⁻¹⁸cm² for He⁺(l²s1/2) -> He⁺(n = …


Radiative Lifetime Of The A¹Π State And The Transition Moment Variation Of The Fourth Positive Band System Of Carbon Monoxide, Joseph George Chervenak Jan 1970

Radiative Lifetime Of The A¹Π State And The Transition Moment Variation Of The Fourth Positive Band System Of Carbon Monoxide, Joseph George Chervenak

Doctoral Dissertations

"The lifetime of the A¹π state of carbon monoxide has been measured using a pulsed invertron excitation source and delayed coincidence measurement technique on the fourth positive system. Eighteen bands, originating from the upper states v' = 0 to 5, were examined at pressures between 500 and 50 microns, with no pressure dependence noted. The data were corrected for photon "pile up" and least-squares fitted to the sum of two exponentials. The transition moment was found to vary and was expanded about the r-centroid of the v' = 0 to v" = 0 transition. Oscillator strengths are calculated and compared …


Upper Cretaceous And Lower Cenozoic Foraminifera Of Three Oil Wells In Northwestern Iraq, Farouk Sunallah Al-Omari Jan 1970

Upper Cretaceous And Lower Cenozoic Foraminifera Of Three Oil Wells In Northwestern Iraq, Farouk Sunallah Al-Omari

Doctoral Dissertations

"Seventy-five samples of well cuttings and cores from the Iraq Petroleum Company Butmah Well No. 9, Ain Zalah Well No. 16 and Ain Zalah Well No. 17, in northwestern Iraq at approximately 36° 37' north latitude and 42° 41' east longitude, have been examined in detail. The lithologic descriptive term "marl" is replaced by calcareous shale or argillaceous limestone, and the term "globigerinal limestone" is not considered applicable. The foraminiferal fauna from the upper part of the Shiranish Formation prove to be of Maestrichtian age. The Mesozoic-Cenozoic boundary is recognized on the basis of "smaller foraminiferal" faunal assemblages; it is …


Discrimination Of Signal And Noise Events On Seismic Recordings By Linear Threshold Estimation Theory, David Nuse Peacock Jan 1970

Discrimination Of Signal And Noise Events On Seismic Recordings By Linear Threshold Estimation Theory, David Nuse Peacock

Doctoral Dissertations

"The object of this study is the investigation of a linear threshold element technique for identifying surface multiples on a single seismic trace. Traces of seismic events were generated which contained primaries, surface multiples, and various levels of Gaussian random noise. Since it was necessary to separate the events as much as possible, the traces were subjected to pulse-compression deconvolution processing prior to LTE analysis. Mean frequency, peak frequency, amplitude spectrum variance, periodicity, and polarity were employed as pattern parameters. A set of weights was found that would maximize the moment of inertia of the S line distribution of the …


Thermochemical Hydrogen-Deuterium Isotope Effects, Wayne C. Duer Jan 1970

Thermochemical Hydrogen-Deuterium Isotope Effects, Wayne C. Duer

Doctoral Dissertations

"The heats of solution at 25.0 ± 0. 1°C for each member of hydrogen-deuterium isotopic pairs (chloroform/chloroform-d, acetone/acetone-d₆, methanol/methanol-d₁, ethanol/ethanol-d₁, and water/heavy water) have been determined as a function of molality in a variety of solvents. The heats for most of the systems could be described as a linear function of average molality with an average deviation in fit of less than one per cent. Using these linear equations, heats of solution at infinite dilution were obtained by extrapolation to zero molality. The heats of solution at infinite dilution of the hydrogen containing compounds were subtracted from those of the …


Extension Of Some Theorems Of Complex Functional Analysis To Linear Spaces Over The Quaternions And Cayley Numbers, James E. Jamison Jan 1970

Extension Of Some Theorems Of Complex Functional Analysis To Linear Spaces Over The Quaternions And Cayley Numbers, James E. Jamison

Doctoral Dissertations

"In this work certain aspects of Functional Analysis are considered in the setting of linear spaces over the division rings of the real Quaternions and the real Cayley algebra. The basic structure of Banach spaces over these division rings and the rings of bounded operators on these spaces is developed. Examples of finite and infinite dimensional spaces over these division rings are given. Questions concerning linear functionals, the Hahn-Banach Theorem and Reflexivity are considered. The Stone-Weierstrass Theorem is proven for functions with values in a real Cayley Dickson algebra of dimension n. The concepts of inner product spaces and Hilbert …


Identification Of Decomposition Products Of Tropyl Azide And Interaction Of Tropylium Ion With Nucleophiles, James Joseph Ward Jan 1970

Identification Of Decomposition Products Of Tropyl Azide And Interaction Of Tropylium Ion With Nucleophiles, James Joseph Ward

Doctoral Dissertations

"An investigation of the structures of several of the products resulting from the decomposition of tropyl azide (I) and of the chemistry of related processes has been undertaken. Irradiation of samples of (I) in the vapor phase with low intensity UV G.E. Sun Lamps furnished a low melting white solid identified as tropyl troponimmonium azide (II). Earlier experiments of a similar nature reported to furnish (III) were not repeatable (Chem. Commun 276 (1967))...

Upon standing, solutions of (I) slowly formed troponimmonium azide (IV) in the cold (J. Chem. Soc. (D), 220 (1970)). The structures (II) and (IV) were confirmed by …


Theory Of Shallow Donor Impurity Surface States, Vidal Emmanuel Godwin Jan 1970

Theory Of Shallow Donor Impurity Surface States, Vidal Emmanuel Godwin

Doctoral Dissertations

"A variational approach has been used to solve the effective-mass equation, when the impurity ion is located at a depth d from the surface of a semiconductor, where 0 < d < db and db represents the case when the impurity ion is in the bulk of the semiconductor. The ground state and the excited state having the largest electric dipole coupling to the ground state have been determined. We have plotted the energy dependence on the depth of the impurity ion from the surface of the semiconductor. The energy has also been calculated as a function of the orientation of the …


A Study Of Far Infrared Grid Filters, Harold Victor Romero Jan 1970

A Study Of Far Infrared Grid Filters, Harold Victor Romero

Doctoral Dissertations

"The diffraction theory for the transmission of electromagnetic fields through a grid in a dielectric is derived and experimentally checked in the visible wavelength region. In the far infrared, an approximate mathematical representation is found to describe the grids in dielectrics. The empirical equations in the far infrared are combined with the electrical circuit-transmission line analog for inductive grids. Detailed structure of the transmittance versus wave number curves are presented. Then the theory of multielement grid filters is derived and compared with experiment. The properties of the filters can be predicted from a knowledge of the characteristics of the individual …


A Heuristic Algorithm For Determining A Constructive Suboptimal Solution To The Combinatorial Problem Of Facility Allocation, Harry Kerry Edwards Jan 1970

A Heuristic Algorithm For Determining A Constructive Suboptimal Solution To The Combinatorial Problem Of Facility Allocation, Harry Kerry Edwards

Doctoral Dissertations

"The major problem in plant layout is to determine the most economical relative location of facilities. There are two distinct types of suboptimal solutions to this combinatorial problem: construction and improvement. The writer has developed Modular Allocation Technique (MAT) which is the first useful construction suboptimal technique. The MAT general algorithm, a theorem relating the MAT solution to the optimal solution and an example problem are given. A computer program has been written that will apply MAT to the allocation problem for a maximum of 40 facilities. Results are given to demonstrate how MAT solutions may be used as initial …


A Quasi-Lattice Model Of Simple Liquids, Jesse Herbert Collins Jan 1970

A Quasi-Lattice Model Of Simple Liquids, Jesse Herbert Collins

Doctoral Dissertations

"A cellular model of simple liquids is proposed which eliminates the objectionable feature of long range order found in other cell models. The volume is divided into N identical spherically symmetric cells, each occupied by one molecule. The cell-center density distribution relative to an average given cell center forms a series of Gaussian peaks whose width is proportional to the square root of the distance from the given cell center. The number of cell centers and average radial distance represented by each of the peaks correspond to a face-centered cubic lattice. The molecular pair distribution function is determined for several …


A Fundamental Investigation Of The Gas Phase Polymerization Of Styrene And Vinyl Type Monomers In A Low Power Inductively Coupled 4 Mhz Rf Plasma, L. F. Thompson Jan 1970

A Fundamental Investigation Of The Gas Phase Polymerization Of Styrene And Vinyl Type Monomers In A Low Power Inductively Coupled 4 Mhz Rf Plasma, L. F. Thompson

Doctoral Dissertations

"A study has been made on the plasma polymerization of styrene and vinyl type monomers in a cold, low power, inductively-coupled RF plasma. All vinyl type monomers yielded an insoluble, crosslinked film which was slightly colored. A kinetic study is reported for styrene. The effects of power level, bleed rate of monomer, pressure and reactor geometry on the rate of polymer formation are reported. A mechanism is postulated for plasma polymerization. It was found that the initiation step was the rate controlling step and that the reaction followed a cationic polymerization scheme. Both crosslinking and discoloration of the polymers occur …


A Coordinate Oriented Algorithm For The Traveling Salesman Problem, Joseph Sidney Greene Jan 1970

A Coordinate Oriented Algorithm For The Traveling Salesman Problem, Joseph Sidney Greene

Doctoral Dissertations

"The traveling salesman problem may be stated as follows: "A salesman is required to visit each of n given cities once and only once, starting from any city and returning to the original place of departure. What route should be chosen in order to minimize the total distance traveled?" A new algorithm is developed which gives a good approximation to the solution for a large number of cities using reasonable computer time and which will converge to the exact solution if allowed to continue. This algorithm is a branch and bound technique which utilizes the distance between cities in its …


Heuristic Algorithms For The Generalized Vehicle Dispatch Problem, Leland Ray Miller Jan 1970

Heuristic Algorithms For The Generalized Vehicle Dispatch Problem, Leland Ray Miller

Doctoral Dissertations

"A heuristic algorithm, called the sweep algorithm, is developed for the vehicle dispatch problem with distance and load constraints for each vehicle. A mathematical development and a step procedure for the sweep algorithm is given. Also given are eight problems and their solutions derived by the sweep algorithm. The solutions for this algorithm are compared with solutions from other vehicle dispatch algorithms, and the sweep algorithm is found to give better results for almost every problem. Various modifications are also presented for the sweep algorithm. A mathematical formulation is given for the vehicle dispatch problem with arbitrary cost functions at …


The Reaction Of N-Sulfinylamines With Diazoalkanes, Harry R. Musser Jan 1970

The Reaction Of N-Sulfinylamines With Diazoalkanes, Harry R. Musser

Doctoral Dissertations

"The photochemical decomposition of diphenyldiazomethane in the presence on N-sulfinylamines leads to ketimines. By-products include tetraphenylethylene, benzophenone, thiobenzophenone, and benzophenone azine. This reaction is the first example of carbene addition to a non-carbon containing multiple bond system. Evidence indicates that the carbene adds to the N=S bond of the N-sulfinylamine to give the corresponding thiaziridine-S-oxide which spontaneously decomposes to give ketimine and SO. In the dark N-sulfinylaniline catalyzes the decomposition of diazoalkanes to carbenes. This decomposition presumably takes place through a thiatriazole-1-oxide intermediate. The carbene then reacts either with N-sulfinylaniline to form ketimine, after loss of SO, or with diazoalkane …


Structures And Relationships Of Some Perovskite-Type Compounds, Christian Michel Jan 1970

Structures And Relationships Of Some Perovskite-Type Compounds, Christian Michel

Doctoral Dissertations

"A model for crystallographic transitions in perovskites is proposed. The model consists of regular octahedra sharing corners and topologically able to rotate without distortion around their three-fold axes. This model, with R3̄c symmetry (18e position) can be described in terms of a continuous rotation of angle, w, of octahedra from two ideal symmetry forms: the hexagonal close-packed and the cubic face-centered configurations. A parametric relation is derived between w and the rhombohedral cell angle, α, or the corresponding hexagonal axial ratio c/a . A wide range of atomic structures based on a framework of regular or slightly distorted octahedra sharing …


An Experimental And Theoretical Study Of The Nucleation Of Water Vapor On Ions In Helium And Argon, Daniel R. White Jan 1970

An Experimental And Theoretical Study Of The Nucleation Of Water Vapor On Ions In Helium And Argon, Daniel R. White

Doctoral Dissertations

"The nucleation of water vapor on ions in atmospheres of helium and argon was studied using an expansion type cloud chamber. Separation of the positive and negative ions was achieved so that the nucleation could be studied as a function of both the sign of the ionic charge and the supersaturation. A semiphenominological theory was developed as an extension of the classical theory to include the effects of the ionic charge on the nucleation process. The theoretical model of the prenucleation embryo was assumed to possess an oriented dipole surface layer with the direction of orientation dependent on the sign …


Completeness And Related Topics In A Quasi-Uniform Space, John Warnock Carlson Jan 1970

Completeness And Related Topics In A Quasi-Uniform Space, John Warnock Carlson

Doctoral Dissertations

"Completions and a strong completion of a quasi-uniform space are constructed and examined. It is shown that the trivial completion of a T₀ space is T₀ . Examples are given to show that a T₁ space need not have a T₁ strong completion and a T₂ space need not have a T₂ completion. The nontrivial completion constructed is shown to be T₁ if the space is T₁ and the quasi-uniform structure is the Pervin structure. It is shown that a space can be uniformizable and admit a strongly complete quasi-uniform structure and not admit a complete uniform structure. Several counter-examples …


Substitution And Photolytic Rearrangements In Three-Member Ring Compounds, Joseph Terril Bohanon Jan 1970

Substitution And Photolytic Rearrangements In Three-Member Ring Compounds, Joseph Terril Bohanon

Doctoral Dissertations

"An investigation into the substitution and photolytic rearrangements of 1,2,3-triphenylcyclopropenes was conducted. Triphenylcyclopropenyl t̲-butyl ether was found to undergo alkyl group exchange with refluxing methanol, ethanol, or 2-propanol to yield the corresponding 1,2,3-triphenylcyclopropenyl alkyl ether when a trace impurity of a 1,2,3-triphenylcyclopropenium halide is present to catalyse the reaction. This forms hydrogen halide with solvent. Upon standing for long periods of time, the 1,2,3-triphenylcyclopropenyl ethers were observed to partially rearrange to new products. A sample of 1,2,3-triphenylcyclopropenyl methyl ether was subjected to photolysis in hexane and yielded 3-methoxy-1,2-diphenylindene, 2,3- diphenylindenone, tolane, benzoic acid, 1,2,3-triphenylpropen-1-one and a polymer. Samples of 1,2,3-triphenylcyclopropene, …


The Electrochemical Behavior Of The Lead-Thallium System In Acidic Sulfate Solutions, Pedro Juan Aragon Jan 1970

The Electrochemical Behavior Of The Lead-Thallium System In Acidic Sulfate Solutions, Pedro Juan Aragon

Doctoral Dissertations

"Although the literature involving the corrosion of pure lead in sulfuric acid solutions is extensive, such studies still constitute an active field of investigation and debate. Much of the effort expended on this subject is due to the need of a better understanding of the reaction in lead storage batteries as well as of the mode of electrocrystallization processes. The resistance of lead to attack by sulfuric acid renders it an important coating material in this media. It is also often used in electrochemical synthesis because of its overvoltage characteristics. Unfortunately its mechanical properties are poor, and many ways have …


The Surface Effects Of Alkali Halides In The Infrared, Vincent Joseph Llamas Jan 1970

The Surface Effects Of Alkali Halides In The Infrared, Vincent Joseph Llamas

Doctoral Dissertations

"The surface state extension of the shallow donor theory is reviewed. The surface state theory and its applications to F-centers of alkali halides is presented. Experimental infrared data show an absorption which seems to correspond with the ground state to first excited state transition. Surface state concentrations of F-centers as a function of depth into the crystal are given. The ratio of surface to bulk cross sections in KBr and experimental calculations of effective masses in various alkali halides are in excellent agreement with theory. The theoretical cross sections are derived from transition probabilities. However, lack of excited states, the …


The Electrochemical Oxidation Of 1-Pentyne On Platinum And Gold, Michael Jensen Danielson Jan 1970

The Electrochemical Oxidation Of 1-Pentyne On Platinum And Gold, Michael Jensen Danielson

Doctoral Dissertations

"The anodic oxidation of 1-pentyne was studied at 70°C on Pt and Au electrodes in solutions of H₂SO₄, K₂SO₄, K₂CO₃, and KOH. Pt was studied in a pH range of 0.35 - 12.7 and Au in a range of 10.9 - 12.7. Reaction rates were measured as a function of potential, pH, temperature, and 1-pentyne partial pressure. The coulombic efficiencies for the oxidation to CO₂ were 77 percent in 1 N H₂SO₄ and 69 percent in 1 N KOH on Pt and 43 percent in 1 N KOH on Au. The kinetic parameters on Pt were [partial derivative]V/[partial derivative]log i …


Linear Regression Models Of Sound Velocity In The North Atlantic Ocean Below A Critical Depth, Richard Roland Kunkel Jan 1970

Linear Regression Models Of Sound Velocity In The North Atlantic Ocean Below A Critical Depth, Richard Roland Kunkel

Doctoral Dissertations

"Sound velocity models currently in use by the U. S. Navy require difficult data sampling at great expense. This study is to investigate the feasibility of a sound velocity model dependent only upon position that would be valid for a selected, reasonably large, near homogeneous area of the ocean. The most important position parameters are latitude, longitude, and depth. To accomplish this objective a critical depth of 2500 meters was established for an 8° by 20° rectangle of the Sargasso Sea which lies within the North Atlantic Ocean. The critical depth is defined as the depth at which the characteristics …