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Articles 1741 - 1770 of 2077
Full-Text Articles in Physical Sciences and Mathematics
The Separation Of Optical Isomers By Gas Chromatography, Donald Ellis Carpenter
The Separation Of Optical Isomers By Gas Chromatography, Donald Ellis Carpenter
Masters Theses
"The purpose of this investigation was to study the separation of optical isomers by gas chromatography. An optically inactive solid support was coated with an optically active substrate. Racemic compounds were used as samples. The optically active packing materials tried were d-tartaric acid, d-diethyl tartrate, sucrose, d-camphoric acid, d-camphor-10-sulfonic acid, α -methyl-D-glucoside and L-(α)-glutamic acid.
Racemic compounds that were tried included 2-butanol, 3-methyl- 2-butanol, 2-methyl-1-butanol, 2-octanol, 2-bromooctane, 2-methoxy-octane, methyl-2-bromobutyrate, and 3-methylhexane.
It was found that racemic compounds could be separated by using an optically active material for packing in the gas chromatographic columns. Racemic 2-butanol, 3-methyl-2-butanol, and 2-methyl-1- butanol were …
An X-Ray Study Of The Lead Titanate-Bismuth Chromate System, Tsen-Tsou Shih
An X-Ray Study Of The Lead Titanate-Bismuth Chromate System, Tsen-Tsou Shih
Masters Theses
"The lead titanate-bismuth chromate system was studied employing x-ray diffraction techniques at both room and high temperatures. Samples were prepared by sintering stoichiometric mixtures of the corresponding oxides followed by air quenching. Bismuth chromate was prepared by resintering and air quenching for four times. The results of the analyses show the structure of BiCrO₃ to be tetragonal with 8 molecules per unit cell. Solid solutions exist over the range 100 to 35 mole percent PbTiO₃ of the binary system, although small amounts of other phases are present in some regions. X-ray data at room temperature indicate the tetragonal perovskite structure …
A Petrofabric Study Of The Iron Ore Of Benson Mines, Star Lake, New York, Remo Antonio Masiello
A Petrofabric Study Of The Iron Ore Of Benson Mines, Star Lake, New York, Remo Antonio Masiello
Masters Theses
"The petrofabrics of the host gneiss silicates and Ovate ore grains were studied in thin sections of oriented specimens collected from widely scattered positions in the iron ore deposit at Benson Mines, New York.
Ten oriented specimens selected for petrofabrics study were comprised primarily of feldspar, quartz, garnet and ores, with lesser quantities of biotite and sillimanite. Petrofabric diagrams were prepared for the orientation fabrics of magnetite and biotite in eight of the ten specimens, but sillimanite and quartz were sufficiently abundant for fabric determination in only three specimens. Duplicate thin section and perpendicular sections were utilized to check the …
Studies In Coprecipitation Of Trace Amounts Of Elements, Gerald Delano Schucker
Studies In Coprecipitation Of Trace Amounts Of Elements, Gerald Delano Schucker
Masters Theses
"A new approach to preconcentration of trace amounts of elements has been demonstrated whereby traces of metals tied up as chelates are coprecipitated on a column of solid organic material. Complete coprecipitation was found to occur within very narrow pH ranges, thereby allowing separation as well as concentration of the elements by careful adjustment of acidity and concentration of chelating agent. The separation is based on the difference in stability constants of the metal chelates. Preliminary studies with different physical forms of the carrier precipitate, indicate adsorptive processes could play a significant role in the mechanism of the column-coprecipitation process. …
Infrared Spectra And Magnetic Properties Of Fluorine Substituted Copper (Ii) Alkanoates, Jose G. Rodriguez
Infrared Spectra And Magnetic Properties Of Fluorine Substituted Copper (Ii) Alkanoates, Jose G. Rodriguez
Masters Theses
"The purpose of this study was to prepare some selected copper(II) fluorcalkanoates, investigate their magnetic susceptibilities, study the infrared spectra of these salts and compare these properties to those of the unfluorinated copper(II) alkanoates….
The experimental data obtained indicate that the copper(II) trifluoroacetate, perfluoropropanoate and perfluorosuccinate does not form a binuclear cage structure. Copper(II) 3-(trifluoromethyl) butanoate with a magnetic moment of 1.4 should possess a binuclear case structure similar to copper( II) acetate monohydrate. The structure for copper( II) perfluoroglutarate monohydrate with a magnetic moment of 1.63 B.M. should have a structure somewhere between the two aforementioned structures"--Abstract, page ii.
The Study Of The Metal Complexes Of Alpha Aminohydroxamic Acids, Richard N. Nipe
The Study Of The Metal Complexes Of Alpha Aminohydroxamic Acids, Richard N. Nipe
Masters Theses
Introduction
The objectives of this investigation were to develop: 1) compounds similar to hydroxy urea, a compound known to have anti-tumor activity, 2) a method to prepare α-aminohydroxamic acids and to study the complexes of these compounds with several metal ions, 3) computer programs to determine the pK's1 of the hydroxamic acids and the stepwise stability constants2 for the ligands and several metal ions.
The values obtained for the stability constants were compared with values for the stability constants of acetohydroxamic acid and α-aminocarboxylic acids in an attempt to find which in the ligand formed bonds with the …
An Investigation Of The Surface Temperature Distribution In The Detroit Region, Allen R. Smith
An Investigation Of The Surface Temperature Distribution In The Detroit Region, Allen R. Smith
Masters Theses
Chapter I
Introduction
Climate and the City
Studies made of temperature in and around cities have shown the climate of the city to be anomalous in relation to its regional climate. The extent of this anomalous condition and the reasons for its occurrence vary from city to city and from season to season. So many variable factors are present in the generation or regeneration of heat within the city that no study has yet satisfactorily explained the total factors involved, or has indicated the percentage for which any one factor might be responsible. This being the case, the only objective …
The Application Of The Verwey-Overbeek Theory To The Relative Sediment Volume Of Kaolin-Water Dispersions, James E. Kline
The Application Of The Verwey-Overbeek Theory To The Relative Sediment Volume Of Kaolin-Water Dispersions, James E. Kline
Masters Theses
Introduction
This paper describes an investigation intended to: 1. observe the effect of electrolyte concentration on the stability of kaolin-water systems, 2. evaluate the relative sediment volume measurement as a tool for determining the stability of such systems, 3. assess the applicability of the Verwey-Overbeek theory of stability of lyophobic colloids for predicting the observed effects, and 4. determine if any correlation exists between the effects predicted by the theory and observed through the relative sediment volume measurement.
The relative sediment volume measurement will be shown to be dependent upon the efficiency of packing of the pigment particles, which in …
Synthesis Of A Substituted Tetrahydropyrimidopyrimidine, Jack Lee Parsons
Synthesis Of A Substituted Tetrahydropyrimidopyrimidine, Jack Lee Parsons
Masters Theses
Introduction
The purpose of this research was to develop a generalized synthesis of substituted tetrahydropyrimidopyrimidines. It was also of interest to prepare related compounds for the purpose of structure determination.
We were interested in tetrahydropyrimidopyrimidines as possible folic acid antagonists.
Dimethyl Sulfoxide Oxidation Of Primary Alcohols, Carmen Vargas Zenarosa
Dimethyl Sulfoxide Oxidation Of Primary Alcohols, Carmen Vargas Zenarosa
Masters Theses
Historical
A method of selective oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones has been developed recently, namely the use of dimethyl sulfoxide (DMSO) as the oxidizing agent, either alone or with dicyclohexylcarbodiimide (DCC)14, acid anhydrides1, or alkyl chloroformates10. The negatively polarized oxygen atom of the sulfoxide group in DMSO is ideally situated for a transfer to many electron-deficient substrates. The oxygen of the alcohol coordinates with the sulfur atom of DMSO through its oxygen atom; this is followed by β-elemination of dimethyl sulfide, thereby resulting in oxidation of the …
Studies On The Preparation Of Tetrasubstituted Hydrazones, William Kao
Studies On The Preparation Of Tetrasubstituted Hydrazones, William Kao
Masters Theses
Introduction
In a recent study of the ultraviolet spectra of substituted hydrazones, it was concluded that a sterio effect existed in tetrasubstituted hydrazones that significantly hindered complete rotation about the nitrogen-nitrogen bond. Weber16 noted that di- and tri-substituted hydrazones exhibited similar spectra with three strong absorption bands at approximately 235, 300, and 340 mu. In acid solutions, the spectra of these compounds showed a marked decrease in intensity of the long wavelength band. It has been postulated that this change was a consequence of the protonation of the non-bonding electron-pair on the amino nitrogen atom, and thus correlated the …
A Synoptic Air Mass Climatology Of The Eastern United States, Robert I. Wittick
A Synoptic Air Mass Climatology Of The Eastern United States, Robert I. Wittick
Masters Theses
Chapter I
Introduction
Orientation and Objective
The concept of the air mass was developed by a group of Norwegian meteorologists during World War I. An air mass, they said, was a body of air which was horizontally homogeneous with respect to temperature and humidity. These bodies of air were classified according to their place of origin since the basic character of an air mass is similar to that of its source region.
Since 1932 when the first air mass climatology was written by Dinies1, the meteorological and geographical journals have published many studies of air mass movements and …
A Study Of The Base Catalyzed Decompositions Of Azoacetates, David V. Herman
A Study Of The Base Catalyzed Decompositions Of Azoacetates, David V. Herman
Masters Theses
Introduction
The formation of a benzyne intermediate has been shown by several investigators (2,5,6) to be developed in at least four different reactions; the reaction of o-dihalobenzenes with magnesium or lithium, aryl halides with strong nucleophiles, o-halobenzophenones with potassium amide in liquid ammonia, and the decomposition of benzenediazonium-2-carboxylate.(13) The mechanism propsed for one of the above most relevant to the following study, the reaction of o-halobenzophenones with potassium amide in liquid ammonia, is outlined in the following sequence:
Studies On The Ribosomal Ribonucleic Acids From Mesophilic And Thermophilic Bacteria, Alice A. Holazo
Studies On The Ribosomal Ribonucleic Acids From Mesophilic And Thermophilic Bacteria, Alice A. Holazo
Masters Theses
Introduction
Certain organisms have been known to live at temperatures at which cellular constituents ordinarily sensitive to heat are destroyed. These organisms. called thermophiles (heat-loving), normally live at higher temperature range of the biokinetic zone (10o-45oC).
Hydrolysis Of Benzohydroxamic Acid, Robert L. Fuller
Hydrolysis Of Benzohydroxamic Acid, Robert L. Fuller
Masters Theses
Introduction
The hydroxamic acids were discovered in 1869 by H. Lossen1. The nomenclature, structure, and chemistry of these compounds have been summarized in an excellent review article by Yale2.
Comparative Analysis Of Numerical Integration Techniques, Edward Lee Sartore
Comparative Analysis Of Numerical Integration Techniques, Edward Lee Sartore
Masters Theses
"When integrating numerically, if the integrand can be expressed exactly as a polynomial of degree n, over a finite interval; then either Simpson's rule, Romberg integration, Legendre-Gauss or Jacobi-Gauss quadrature formulas provide good results. However, if the integrand can not be expressed exactly as an nth degree polynomial, then perhaps it can be expressed as a function f(x) divided by √1-x 2, or as a function g(x) times (1-x)α (l+x)ß , where α and ß are some real numbers >1, or as a function h(x) times one. If this is the case then the Chebyshev-Gauss, Jacobi-Gauss, and …
A Study Of The Development Of A Heuristic Program That Solves Symbolic Laplace Transformation Problems, Arthur E. Zackrison
A Study Of The Development Of A Heuristic Program That Solves Symbolic Laplace Transformation Problems, Arthur E. Zackrison
Masters Theses
"A medium-speed general purpose digital computer (IBM 1620 Model II) was programmed to solve symbolic Laplace transformation problems. Although the applied mathematician and modern engineer has many uses for the symbolic solution of a problem, the potential of symbolic manipulation by a computer has not yet been sufficiently developed to help them because of many problems. This paper discusses the program and based on the author’s experience with it’s [sic] performance, clarifies the position of several of these difficulties and reaches some conclusions concerning computer solution of such problems"--Abstract, page ii.
Origin And Factors Affecting Distribution Of Solid Oil In Mid-Western Missouri, Rafid Abdul-Halim Jasim
Origin And Factors Affecting Distribution Of Solid Oil In Mid-Western Missouri, Rafid Abdul-Halim Jasim
Masters Theses
"A textural analysis was made of the heavy oil-bearing sandstones in the Middle Pennsylvanian (Desmoinesian) Warner and Bluejacket formations of mid-western Missouri in order to determine and compare their depositional environments.
Grains of the Bluejacket sandstones are smaller and more rounded than grains of the Warner sandstones. The Bluejacket sandstone is also better sorted than the Warner sandstone.
The Bluejacket sandstone is thin-bedded; the Warner is mostly massive-bedded. These differences in bedding between the two formations have affected distribution of oil in the area of study.
Both the Bluejacket and Warner sandstones are better sorted than the Warrensburg sandstones; the …
The Activity Of Succinic Dehydrogenase And Indole Acetic Acid Oxidase In Cell-Free Preparations Of Hygrophorous Conicus, Jagdish M. Mehta
The Activity Of Succinic Dehydrogenase And Indole Acetic Acid Oxidase In Cell-Free Preparations Of Hygrophorous Conicus, Jagdish M. Mehta
Masters Theses
"The enzyme indole acetic acid oxidase is produced by the fungus Hygrophorous conicus when it is grown in the presence of indole acetic acid (IAA) or tryptamine. The IAA acts both as an inducer and a substrate for this intracellular enzyme. The product of the oxidation catalyzed by the IAA oxidase is oxindole acetic acid (OIAA).
The rate of growth and the rate of formation of the enzyme IAA oxidase by H.conicus were studied in different media. Of these, a nitrate medium containing 0.5 per cent Yeast extract (Y.E.) was found to be the best for the production of H.conicus …
A Comparison Of The Lr And Qr Transformations For Finding The Eigenvalues For Real Nonsymmetric Matrices, Susan Clara Hanson
A Comparison Of The Lr And Qr Transformations For Finding The Eigenvalues For Real Nonsymmetric Matrices, Susan Clara Hanson
Masters Theses
"The LR and QR algorithms, two of the best available iterative methods for finding the eigenvalues of a nonsymmetric matrix associated with a system of linear homogeneous equations, are studied. These algorithms are discussed as they apply to the determination of the eigenvalues of real nonsymmetric matrices.
A comparison of the speed and accuracy of these transformations is made. A detailed discussion of the criterion for convergence and the numerical difficulties which may occur in the computation of multiple and complex conjugate eigenvalues are included.
The results of this study indicate that the QR algorithm is the more successful method …
The Faraday Rotation And Dispersive Doppler Effects In The Ionosphere At Oblique Incidence, Charles Roland Baugher Ii
The Faraday Rotation And Dispersive Doppler Effects In The Ionosphere At Oblique Incidence, Charles Roland Baugher Ii
Masters Theses
"Integral equations for the isotropic and anisotropic ray path of a radio wave propagating through the ionosphere are developed. These equations assume a spherically stratisfied ionosphere and are equivalent to a detailed ray-tracing process. A method is devised to utilize these equations in the evaluation of combined Faraday rotation and dispersive Doppler data from earth satellites for subionospheric electron content. The method, which corrects for horizontal ionospheric gradients, is applied to data from the Explorer 22 satellite and some preliminary results are discussed"--Abstract, page ii.
Structure Contours On The Top And Base Of The M Bed, The Relationship Of Mineralization To Structures, And The Variation Of The M Bed Thickness In The Tri-State District, Missouri, Kansas And Oklahoma, Arvind A. Desai
Masters Theses
"Regional structure and thickness of a single horizon, the M bed, have been studied in the Tri-State district by picking the top and base of the M bed in the logs of 557 selected drill holes and contouring this data together with the aid of local detailed structural information available for individual mining fields. Structures determined from these data were compared to the positions of mined mineralization to determine the control of regional structure upon the localization of ore. Variations in the M bed thickness were compared to the positions of fields of mineralization to examine possible spatial relationships which …
The Construction Of A Multi-Threshold Foil For Fast Flux Measurements, Michael Henry Holkenbrink
The Construction Of A Multi-Threshold Foil For Fast Flux Measurements, Michael Henry Holkenbrink
Masters Theses
"The construction of a multi-threshold foil for fast neutron flux measurements is investigated. The factors governing the selection of the materials are the energy response of the given reactor, the half-life of the daughter, the prominent gamma ray emitted during decays, the power level of the reactor, the availability of adequate cross section data, and the alloying properties of the composite foil. A ternary system was chosen as a compromise between the difficulty of fabrication and the amount of information gained from one foil. The particular system chosen was In- P- Fe. The threshold reactions of these elements are In¹¹⁵ …
A Simulation Study Of A Proposed Computer Installation, John Edward Hawthorne
A Simulation Study Of A Proposed Computer Installation, John Edward Hawthorne
Masters Theses
"The operation of a data processing center has been studied with the objective of investigating the effect of various facilities, job loads, and operating policies as measured by job turnaround time. The mechanism for study was digital computer simulation.
This thesis purports to review the technology of simulation and the associated computer techniques, defines the problem and the alternatives available, and analyzes the results derived from the experiments.
Conclusions drawn from this study support the current practice of a functioning data processing center"--Abstract, page ii.
Tectonic Analysis Of Mare Humorum On The Lunar Surface, Adnan Said Abul-Husn
Tectonic Analysis Of Mare Humorum On The Lunar Surface, Adnan Said Abul-Husn
Masters Theses
"Morphology and internal structures of surface features of the Mare Humorum area were interpreted from photographs and topographic maps. The postulated origin of certain features is based on analog comparisons with known terrestrial features. The laws of crate ring and a newly developed computer program were applied to two representative classes of craters to determine the possibility of a meteoritic impact origin. Some of the craters formed by meteoritic impact and others, including those with a radius larger than 10 Km, probably resulted from volcanic activity.
Mare Humorum formed from centripetal subsidence followed by extensive lava eruptions. Spacially related rilles …
Upper Cretaceous-Lower Cenozoic Foraminifera From An Oil Well In Northwestern Iraq, Farouk Sunallah Al-Omari
Upper Cretaceous-Lower Cenozoic Foraminifera From An Oil Well In Northwestern Iraq, Farouk Sunallah Al-Omari
Masters Theses
"Twenty-five samples of well cuttings from the Iraq Petroleum Company Butmah Number 9 Well in northwestern Iraq, at approximately 36° 37' north latitude and 42° 41' east longitude, have been examined in detail. The boundary between the Upper Cretaceous and lower Cenozoic is recorded as closely as possible on the basis of the microfaunal assembalges. A unit showing equivalence to the Danian Stage also is recognized"--Abstract, page ii.
The Mössbauer Effect In Bismuth Ferrate, Bruce A. Banks
The Mössbauer Effect In Bismuth Ferrate, Bruce A. Banks
Masters Theses
"The magnetic hyperfine structure of the Fe⁵⁷ nuclei in bismuth ferrate was investigated using the Mössbauer effect. A Mössbauer effect spectrometer was built with consideration given to the elimination of vibration and the optimizing of the source, absorber, and detector geometries to produce the largest fractional Mössbauer effect per fractional standard deviation. The internal magnetic field at the Fe nuclei in BiFeO₃ was determined to (482 ± 9) kilooersteds at room temperature"--Abstract, page ii.
Ecology And Distribution Of Foraminifers Of A Traverse In The Northwestern Gulf Of Mexico, Faiz Nassir Thomas
Ecology And Distribution Of Foraminifers Of A Traverse In The Northwestern Gulf Of Mexico, Faiz Nassir Thomas
Masters Theses
"Foraminiferal populations have been analyzed from five bottom samples along a traverse in the northwestern Gulf of Mexico, approximately 27⁰20' to 97⁰15' north latitude and 97⁰20' to 97⁰05' west longitude. Eighty-eight species and twenty-nine genera, belonging to eighteen families, were recorded. Species were identified and described.
Statistical studies indicate that probably five benthonic foraminiferal depth facies could be recognized in the area at the following approximate depths: 4 fathoms, 4-8 fathoms, 8-12 fathoms, 12-16 fathoms, and 16-20 fathoms. Determination of facies is based largely on the range of species. The frequency distribution of species of foraminifers was plotted against change …
A Mathematical Study Of Voigt Viscoelastic Love Wave Propagation, David Nuse Peacock
A Mathematical Study Of Voigt Viscoelastic Love Wave Propagation, David Nuse Peacock
Masters Theses
"This research is a mathematical investigation of the propagation of a Love wave in a Voigt viscoelastic medium. A solution to the partial differential equation of motion is assumed and is shown to satisfy the three necessary boundary conditions. Velocity restrictions on the wave and the media are developed and are shown to be of the same form as those governing the elastic Love wave"--Abstract, page ii.
Two-Dimensional Seismic Model Studies, Joong Hee Chun
Two-Dimensional Seismic Model Studies, Joong Hee Chun
Masters Theses
"The purpose of this research was to design and construct apparatus suitable for two-dimensional seismic model studies.
A new technique for two-dimensional seismic model testing was devised which allows wide application of the equipment. This enabled the author to place the source and receiver in any desired position on the model, thereby permitting the recording of seismic events as function of distance and depth at any position
Two simple geometric models were tested to demonstrate the experimental range of the apparatus designed. The recorded data were compared with theoretical predictions and were found to be in good agreement"--Abstract, page ii.