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Articles 1861 - 1890 of 2070
Full-Text Articles in Physical Sciences and Mathematics
The Reaction Of Sodium Iodide In Acetone With Halogenated Epoxides -- A Mechanism Study, Thomas E. Breuer
The Reaction Of Sodium Iodide In Acetone With Halogenated Epoxides -- A Mechanism Study, Thomas E. Breuer
Masters Theses
"l-bromo-2,3-epoxybutane reacted with sodium iodide in acetone to give 3-iodo-l,2-epoxybutane in 70.1 per cent yield. 3-bromo-l,2-epoxybutane produced l-iodo-2,3-epoxybutane in 69.9 per cent yield when it was allowed to react with a solution of sodium iodide in acetone. No other product could be isolated after either reaction, although it is possible that another compound may have been produced in very small amounts. The iodoepoxides were oxidized to the corresponding α-iodoacid in approximately ninety per cent yield by silver oxide"--Summary, page 40.
The Anodic Dissolution Of Zinc In Aqueous Solutions, Glenn E. Stoner
The Anodic Dissolution Of Zinc In Aqueous Solutions, Glenn E. Stoner
Masters Theses
"The increasing demand for protective metals as coatings and non-corrosive alloys has stimulated extensive research on the fundamental behavior of metals in corrosive media.
One of the problems still unsolved is the nature of the mechanism of the anodic dissolution of metals like zinc, magnesium, beryllium, cadmium, and aluminum in aqueous salt solutions. Several schools of investigators have proposed different and opposing theories to explain the discrepancies which often arise between coulometric data and the weight loss of metal electrodes in certain salt solutions.
The purpose of this investigation was to obtain experimental data for the anodic dissolution of zinc …
Investigation Of Measures Of Ill-Conditioning, Thomas D. Calton
Investigation Of Measures Of Ill-Conditioning, Thomas D. Calton
Masters Theses
“The object of investigation in this study is that of ill-conditioning in the solution of a system of linear equations. Ill-conditioning arises when the solution is very sensitive to small changes in the coefficients of the unknowns.
A study is made in this paper of the various proposed measures of ill-conditioning for the purpose of finding the most practical method or measure for determining whether a system is ill-conditioned.
The problem of near-singular or ill-conditioned systems is of great importance in the solution of linear systems because of the extensive use made of them in practical situations. Solution of a …
Spin Relaxation Of Optically Pumped Rubidium., Kenneth Brian Steinbruegge
Spin Relaxation Of Optically Pumped Rubidium., Kenneth Brian Steinbruegge
Masters Theses
"This Thesis is intended to be a self-contained guide to the theory and experimental procedures of optical pumping in one of its most usual applications. A particular study is made of optical pumping of rubidium vapor and results are given stating the most efficient temperature range in which to produce large populations of optically oriented rubidium atoms. The thermal relaxation time for optically orientated rubidium for a particular system is given and the effect of trapped resonance radiation is considered in the interpretation of the experimentally obtained curves"--Abstract, p. ii
The Measurement Of The Life-Time Of The 62P3/2 State Of Thallium, Danny Hale Sokolowski
The Measurement Of The Life-Time Of The 62P3/2 State Of Thallium, Danny Hale Sokolowski
Masters Theses
The measurement of the lifetime of the metastable 62P3/2 state of thallium is discussed. Time-sampling equipment techniques and instantaneous methods of display on an oscilloscope for measuring the lifetime are explained. The lifetime is measured as a function of mercury vapor pressure. The decay of the 5350 A thallium line is also measured to give an indication of the effect of the imprisonment of the 3776 A resonance line. This decay of the 5350 A line is also in a mercury atmosphere"--Abstract, page ii.
Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone
Stereoradiography As Applied To Problems Of Petrology., Martin Goldstone
Masters Theses
"Stereoscopic examination of radiographs of rock and ore samples allows a rapid, cursory determination of texture and structure without time consuming preparation and use of thin sections. In addition, volumetric estimates of known mineral components can be made providing they possess significantly different x-ray absorption characteristics.
Stereoscopic effect was most pronounced for specimens having well defined components of structure such as bedding, banding, lineation, inclusions, textural variations and moderate to large x-ray absorption differences. In general, these conditions were best met by ores or ore minerals with their related gangue minerals.
Stereoscopic examination was not successful in revealing twinning or …
Fossil And Recent Beryciform Otoliths: An Adjunct To Ichthyological Classification., C. Kurt. Lamber
Fossil And Recent Beryciform Otoliths: An Adjunct To Ichthyological Classification., C. Kurt. Lamber
Masters Theses
"Otoliths are calcareous bodies, of consistent form, secreted in the auditory labyrinths of some higher fishes. Of three pairs, only the taxonomically important earstones (sagittae) are considered here. Specifically, this study is restricted to the sagittae of beryciform fishes (Order Beryciformes). Removal of some taxa from the order, and the possible relating of others, is suggested.
The morphology of beryciform sagittae is described, and three basic supra-familial groups are recognized. Diagnostic characters for families are given, with diagnoses of genera added. Sagittae of characteristic species are illustrated.
Otoliths of fossil beryciform fishes, as known from specimens and published illustrations, are …
Geology Of The Northern Half Of The Ellington Quadrangle Missouri., Robert Charles. Thornton
Geology Of The Northern Half Of The Ellington Quadrangle Missouri., Robert Charles. Thornton
Masters Theses
"Geologic mapping has been completed for the northern half of the Ellington Quadrangle, Missouri. Rocks exposed in the thesis area are Precambrian and Paleozoic in age. The Precambrian rocks are granites and felsite. The Paleozoic rocks include the Potosi and Eminence Formations, of Upper Cambrian age, and the Gasconade Formation of Ordovician age. Distinction between the Potosi and Eminence Formations is difficult because of conformable and transitional relationships. In the thesis area sufficient evidence was available to separate the dolomites of the Potosi and Eminence as mappable units. This mapping should be useful as a basis for more detailed geologic …
The Application Of Quantum-Mechanical Concepts To Biological Systems, Andrew A. Cochran
The Application Of Quantum-Mechanical Concepts To Biological Systems, Andrew A. Cochran
Masters Theses
"The relation between quantum-mechanical concepts and biological systems is explored by studying the relation of both to the concepts of heat capacity and entropy. It is shown that the most important substances in living matter have extremely low heat capacities and entropies at ordinary temperatures. A critical analysis of the two types of quantum-mechanical interactions between particles and the interactions occurring in low-entropy systems shows that the wave properties of matter are strongly predominant in the chemical elements that constitute 99 percent of living matter. It is concluded that the wave aspects of matter are strongly predominant in biological systems. …
Mathematical Techniques In The Solution Of Boundary Value Problems., Vincent Paul Pusateri
Mathematical Techniques In The Solution Of Boundary Value Problems., Vincent Paul Pusateri
Masters Theses
"This study was undertaken to present a summary of mathematical techniques as applied to the solution of boundary value problems in partial differential equations.
The techniques that were presented can be considered to be some of the most popular in applied science.
The salient features of the study are that different techniques can present different analytical expressions for a solution to the same boundary value problem, and from the viewpoint of computation and accuracy one solution may prove more desirable than the other.
The study also indicates that in boundary conditions where finite discontinuities exists, a slight perturbation to remove …
Permeation Of Water Vapor Through Linear Polymer Films, Mohammed S. Rifai
Permeation Of Water Vapor Through Linear Polymer Films, Mohammed S. Rifai
Masters Theses
"Film formation from thermoplastic resin solutions Is Influenced by secondary intermolecular forces. Consider what may happen when organic coatings change from a liquid to a solid state. In the liquid state it is logical to consider the linear polymer molecules as agglomerates being dispersed in the volatile component rather than being present In solution. These molecular agglomerates are referred to as micelles. They have various degrees of orientation depending on the extent and the location of dipole forces in both polymer and solvent molecules.
When a coating is applied the solvent starts to evaporate and the micelles are driven closer …
The Sacajawea Formation And The Darwin Sandstone In The Southeast Wind River Mountains, Wyoming, Denny N. Bearce
The Sacajawea Formation And The Darwin Sandstone In The Southeast Wind River Mountains, Wyoming, Denny N. Bearce
Masters Theses
"The area under study is located along the southeast flank of the Wind River Range in Fremont County, Wyoming, Beds overlying the Madison Group are measured and described in six locations within this area. These locations are: Worth Fork Popo Agie River, Sink’s Canyon, Crooked Creek, Canyon Creek, Little Popo Agie River, and Cherry Creek.
Laboratory studies are used as an aid in correlating the sandstone and dolomite sequences described In the six sections. These studies include sieve and heavy mineral analyses and thin section examination.
Sorting factors, obtained from the sieve analyses, and heavy mineral suites indicate that the …
A Modified Algorithm For Henrici's Solution Of Y' ' = F (X,Y), Frank Garnett Walters
A Modified Algorithm For Henrici's Solution Of Y' ' = F (X,Y), Frank Garnett Walters
Masters Theses
"The purpose of the present study is to discuss the boundary value problems leading to equations exemplified by the four equations previously mentioned and to write a program for an I.B.M. computer in Fortran II language as a contribution to the numerical solution of an important class of linear and nonlinear differential equations"--Introduction, page 4.
A Numerical Approach To A Sturm-Liouville Type Problem With Variable Coefficients And Its Application To Heat Transfer And Temperature Prediction In The Lower Atmosphere., Troyce Don Jones
Masters Theses
No abstract provided.
Electronic Data Processing--Its Place In The Administrative And Academic Areas At Eastern Illinois University, John Walstrom
Electronic Data Processing--Its Place In The Administrative And Academic Areas At Eastern Illinois University, John Walstrom
Masters Theses
No abstract provided.
An Investigation Of Drift-Covered Environments Using The Shallow Reflection Seismic Method, Kalamazoo County, Michigan, Thomas Patrick Luby
An Investigation Of Drift-Covered Environments Using The Shallow Reflection Seismic Method, Kalamazoo County, Michigan, Thomas Patrick Luby
Masters Theses
Seismic work utilizing a six-channel analog seismograph and a hammer impact source successfully obtained coherent reflection events from horizon within the glacial overburden, from the drift-paleozoic interface, and from Paleozoic bedrock targets. Fieldwork was conducted in eight drift-covered environments where the drift thickness varied from 80 feet to greater than 500 feet. Factors that exerted a major control over the seismic response at each environment studied include the depth of the water table, the type of surface material underlying the shot point and geophone spread, and the use of single versus multiple geophones per channel. Each of these factors influenced …
The Correlation Of Spectra And Steric Effects In Alkyl And Aryl Hydrazones, Dennis J. Weber
The Correlation Of Spectra And Steric Effects In Alkyl And Aryl Hydrazones, Dennis J. Weber
Masters Theses
Introduction
The correlation of spectra, especially ultraviolet spectra, of hydrazones with their structure has resulted in considerable confusion because of the variations in spectra obtained from apparently the same basic chromophore.
The Construction Of Two Light Sources With Adequate Intensity For Magneto-Optical Rotatory Dispersion Experiments, Norman D. Love
The Construction Of Two Light Sources With Adequate Intensity For Magneto-Optical Rotatory Dispersion Experiments, Norman D. Love
Masters Theses
Chapter I
Introduction
The phenomenon known as the Faraday Effect was discovered by Michael Faraday in the year 1845.1 He discovered that when an isotropic substance of high refractive index is placed in a strong magnetic field which is parallel to a beam of plane polarized light, the plane of polarization is rotated. The rotation is proportional to H, the strength of the magnetic field; and to 1, the length of the light path in the sample. If X represents the rotation in minutes then
X = VH1.
The proportionality constant V is known as Verdet's constant. The units …
Attempts In The Synthesis Of T-Alkylhydrazines, Richard A. Evans
Attempts In The Synthesis Of T-Alkylhydrazines, Richard A. Evans
Masters Theses
Introduction
Interest in t-alkyhydrazines has developed from the recent preparation of azoacetates (5) by the leadtetra-acetate oxidation of hydrazones
Geology Of The Esterbrook Area, Converse And Albany Counties, Wyoming, Michael Nolan Greeley
Geology Of The Esterbrook Area, Converse And Albany Counties, Wyoming, Michael Nolan Greeley
Masters Theses
"The Esterbrook area lies within the Laramie Range in Converse and Albany Counties, Wyoming. Exposures include Precambrian metamorphic and igneous rocks, the Tertiary White River formation, and Quaternary alluvium.
Hornblende schist and mica-quartz schist comprise the Precambrian metamorphic rocks. Foliation planes of these rocks trend northeast and dip steeply to the southeast. Metamorphic rocks of younger age probably lie to the southeast.
A distinctive, Precambrian silicic pluton of biotite-leucogranite with marginal zones of muscovite-leucogranite and alaskite passively intrudes the metamorphic rocks, generally parallel to the foliation trends. Numerous granite pegmatites show a zonal distribution around the pluton and appear to …
Variation Of Sensitized Fluorescence With Penetration Depth Of Incident 2537a Radiation, George Grayson Robinson
Variation Of Sensitized Fluorescence With Penetration Depth Of Incident 2537a Radiation, George Grayson Robinson
Masters Theses
"An investigation of the sensitized fluorescence of a thallium and mercury mixture using a variable depth cell and photomultiplier type of detection is discussed. Data are given to indicate the variation of the intensity of the 3519A thallium line as a function of thallium temperature, as a function of mercury temperature, and as a function of cell depth. Explanations of results require the use of generally accepted ideas concerning energy transfer, emission, and absorption."
Studies Involving Modification Of The Megregian Method Of Fluoride Determination And Application To Fluoride Balance Studies In Infants, Gene R. Wright
Studies Involving Modification Of The Megregian Method Of Fluoride Determination And Application To Fluoride Balance Studies In Infants, Gene R. Wright
Masters Theses
Introduction
At the request of Dr. Frederick Margolis, M.D., and in association with The Upjohn Company, this research problem was initiated as a participation in the investigation of whether or not fluoride ingested as a constituent of the Upjohn 47-M liquid vitamin preparation is retained in an infant's body to the same extent as is fluoride ingested as the sodium salt by itself--either in solution or in tablet form. The retention patterns may be studied indirectly by measuring the amounts of fluoride excreted in the urine and in the feces during each of a series of equal time intervals after …
The Separation Of Germanium From Lead, Cadmium, And Zinc By Ion Exchange, Myra Sue Anderson
The Separation Of Germanium From Lead, Cadmium, And Zinc By Ion Exchange, Myra Sue Anderson
Masters Theses
"The object of this study was to investigate the ion exchange behavior of germanium in order to find a quantitative separation method applicable to the analysis of germanium in zinc ores.
Germanium had been predicted and described as eka-silicon by Mendeleeff, and was discovered by Winkler in 1886. The importance of the metal has increased very much since World War II because of its use as a semiconductor in diodes and transistors.
All commercial scale germanium is now produced as a by-product of base metal processing. Although the United States Bureau of Mines is conducting a program for the recovery …
The Reaction Of N-Magnesium Halides On Nitriles In The Synthesis Of Amidines, Robert Bauer
The Reaction Of N-Magnesium Halides On Nitriles In The Synthesis Of Amidines, Robert Bauer
Masters Theses
Introduction
Compounds of the amidine class have long been of interest because of their therapeutic and pharmacological properties. Members of this class of compounds have been shown to be effective in combating pathological conditions ranging from virus (11), bacterial (12), and protozoal infections (7) to diseases of the circulatory system (6), neoplasms (5) and hyperglucemia (21), Since many basic nitrogen compounds have been of interest in cancer chemotherapy, such as a variety of amino alcohols shown by the Upjohn Company to have anti-tumoral activity, it was felt that additional investigations into the use of amidines and amino amidines in this …
K₂O/Na₂O Content As A Possible Index To The Chronological Sequence Of Some Precambrian Igneous Rocks Of Missouri, Erwin Joseph Mantei
K₂O/Na₂O Content As A Possible Index To The Chronological Sequence Of Some Precambrian Igneous Rocks Of Missouri, Erwin Joseph Mantei
Masters Theses
"Flame photometric analyses for K₂O and Na₂O were run on 31 samples of the Precambrian igneous rocks of Missouri. Samples were collected from the field, physically prepared and dissolved by a standard method and a modified standard method of rapid silicate analyses. The K₂O, Na₂O values obtained are averages between two methods of analyses. The modified method reduces by 80% the time required to chemically digest a rock sample. The results for both methods are not significantly different. Curtin and Company Advanced Flame Photometer was used.
Results have been plotted on graphs and a chronological sequence for the named Precambrian …
An Investigation Of Lehmer's Method For Finding The Roots Of Polynomial Equations Using The Royal-Mcbee Lgp-30, James W. Joiner
An Investigation Of Lehmer's Method For Finding The Roots Of Polynomial Equations Using The Royal-Mcbee Lgp-30, James W. Joiner
Masters Theses
“The solution of the general polynomial equation f (x) = O, where f(x) = anxn + an-1xn-1 + … + a1x = ao, has received the attention of many mathematicians for hundreds of years and is at present in a very highly developed state. Even a cursory examination of the literature will reveal many volumes on this subject. However, this study is concerned primarily with the numerical methods for solving polynomial equations, hence the classical methods will be treated here only as they contribute to this field.
Virtually all of …
Syntheses And X-Ray Investigations Within The System Fes₂-Cos₂, Samuel Shu Mou Chan
Syntheses And X-Ray Investigations Within The System Fes₂-Cos₂, Samuel Shu Mou Chan
Masters Theses
"Pyrite (FeS2), cattierite (CoS2), and various transitional members of the solid solution compounds were prepared. The methods used are as follows:
First, sulfides of cobalt, iron, or cobalt-iron were obtained by precipitation from a mixture of the cobalt chloride and/or ferrous sulfate in an aqueous solution. The dried precipitates were then mixed with an equal weight amount of sulfur and placed into silica glass tubes. After evacuation, they were filled with hydrogen gas of 3/4 of atmospheric pressure and sealed. The samples were then heated up to 500°C (for FeS2), 650°C (for FeS2 …
Foraminifera Of The Cenozoic And Recent Genus Sphaerogypsina Galloway, Wayne C. Horton
Foraminifera Of The Cenozoic And Recent Genus Sphaerogypsina Galloway, Wayne C. Horton
Masters Theses
"The morphology of Sphaerogypsina as seen in thin section affords various characters useful in classification] 1) arrangement and composition of the wall (calcareous-perforate, radially crystalline); 2) layering of wall (like Gypsina, without layering or black line, having only microlamellae); 3) shape of test (always spherical); and 4) specific characters: size of test, order/unorder ratio, size of chambers, wall thickness, pore diameter, and type of embryonic apparatus.
Correlation of the above characters has allowed recognition of two new species. Comparisons with other genera strongly suggest placing the genus in the Family Gypsinidae (nom. correct.) rather than in the …
Application Of Digital Computer To Magnetic Data Interpretation Using Surface Integral Method, Afif Hani Saad
Application Of Digital Computer To Magnetic Data Interpretation Using Surface Integral Method, Afif Hani Saad
Masters Theses
"A simple method is developed for the calculation of the magnetic effect due to three-dimensional bodies. The method is based on the use of surface integration instead of volume integration. Thus, any three-dimensional body can be considered as having two surfaces, upper and lower, with magnetic pole distributions. Simple equations based on potential theory have been derived for the calculation of the vertical component and total intensity due to these surface distributions of poles. The anomalous field of the body can be obtained by subtracting the effect due to one of the surfaces from that of the other.
The method …
Seismic Investigation Of Flint Clay Deposits In East Central Missouri, Roland D. Dayley
Seismic Investigation Of Flint Clay Deposits In East Central Missouri, Roland D. Dayley
Masters Theses
"Seismic refraction surveys were conducted in several localities within the east central Missouri clay districts in order to determine the applicability and economy of this method as a clay exploration tool. Results of these surveys revealed that the sink-type clay deposits possess lithologic and structural characteristics that lend themselves favorably to this method of exploration.
Seismic records obtained from profiles shot across known deposits indicate that several factors other than velocity contrast serve to produce apparent seismic anomalies.
Some unforeseen time loss and expense was encountered because of malfunctions of the seismic equipment employed, which necessitated the purchase and installation …