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Articles 1801 - 1830 of 2070
Full-Text Articles in Physical Sciences and Mathematics
Studies On The Conversion Of Indole Acetic Acid And Oxindole Acetic Acid By Hygrophorous Conicus, Barbara Ruth Patterson
Studies On The Conversion Of Indole Acetic Acid And Oxindole Acetic Acid By Hygrophorous Conicus, Barbara Ruth Patterson
Masters Theses
"The fungus, Hygrophorous conicus, produces the enzyme, indole acetic acid oxidase, when 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). Since the IAA and OIAA absorb maximally at two different wavelengths the use of spectrophotometric analysis was possible for assaying for the IAA oxidase activity. Paper chromatography was used for qualitative identification of the IAA and OIAA. The rate of growth and the rate of formation of the …
Thermal Hydrolysis And Structure Studies On Cobalt (Ii) Acetate, Russell J. Hesch
Thermal Hydrolysis And Structure Studies On Cobalt (Ii) Acetate, Russell J. Hesch
Masters Theses
"The object of this study was to investigate the structure of cobalt (II) acetate, isolated from glacial acetic acid, without recourse to standard x-ray methods"--Introduction, page 1.
The Geology Of The Interstate Highway 244 And 44 Exchange, Kirkwood, Missouri, John Neil Thomas
The Geology Of The Interstate Highway 244 And 44 Exchange, Kirkwood, Missouri, John Neil Thomas
Masters Theses
"During the summer of 1964, construction was completed on the intersection of Interstate Highways 244, 44 and U.S. Highway 66, one mile southwest of Kirkwood, Missouri. during the construction of the interchange, numerous artificial exposures of rocks of the middle Mississippian Meramecian Series were exposed. This provided an excellent opportunity for examining fresh exposures near the type Meramecian Series. The formations of the area were studied, and startigraphic [sic] sections were prepared from three of the more complete sections that were measured and described. The highway cuts expose complete sections of the Warsaw and Salem formations, and the lower part …
Stereochemistry Of Chlorinated Diels-Alder Adducts, Harry R. Musser
Stereochemistry Of Chlorinated Diels-Alder Adducts, Harry R. Musser
Masters Theses
"Hexachlorocyclopentadiene and related compounds have been studied extensively in connection with Diels-Alder reactions. Many of the adducts formed are used as intermediates in insecticide syntheses. It is of interest to study the stereochemistry of the adducts of one of the hexachlorocyclopentadiene derivaites. 5,5-Dimethoxy-1,2,3,4-tetrachlorocyclopentadiene and various dienophiles, when allowed to react, yield compounds of the bridges bicyclo [2.2.1] hept-2-ene series. The study of the endo and/or exo configuration of various functional groups such as carboxyl, aldehyde, and hydroxymethyl can be related to the known exo-5-hydroxymethyl1-1,2,3,4-tetrachlorobicyclo-[2.2.1] help-2-ene-7-one"--Introduction, page [1].
Geology, Geochemistry And Genesis Of Selected Skarn Deposits, Northern New Brunswick, Canada, Donald John Bachinski
Geology, Geochemistry And Genesis Of Selected Skarn Deposits, Northern New Brunswick, Canada, Donald John Bachinski
Masters Theses
"An exhaustive geological and geochemical study is presented of magnetite-chalcopyrite skarn deposits occurring within the thermal aureole of the Nicholas Denys quartz maonzonie-granodiorite stock. The deposits are crudely lenticular and occur in metamorphosed impure limestone and siliceous, in part limy, argillite-greywacke. These are now represented by andradite-epidote-diopside-calcite skarn and cal-silicate to horn-felsic rocks respectively. Both deposits are spatially related to the Main fault of the Rocky Brook-Millstream fault system; late, generally northwest trending transverse faults are conspicuous and are deemed of importance in ore localization"--Abstract, page [ii].
Zinc And Copper Content Of Stream Sediment In South-Central Missouri, Shih-Cheang Cheng
Zinc And Copper Content Of Stream Sediment In South-Central Missouri, Shih-Cheang Cheng
Masters Theses
"Thirty samples of stream sediment from the North Fork River, Bryant Creek and related tributaries in south-central Missouri have been analyzed for cold-extractable copper, cold-extractable heavy metal, total copper and total zinc.
Cold-extractable copper varies from 0 to 10 ppm and averages less than 1 ppm; cold-extractable heavy metal varies from 3 to 30 ppm and averages 12 ppm; total copper varies from 50 to 200 ppm and averages 88 ppm; total zinc varies from 20 to 300 ppm and averages 86 ppm.
The pH of the stream water appears to have no affect on the metal content of the …
A Second Study Of Homogeneous Nucleation Of Water Vapor In Helium, Raymond J. Schmitt
A Second Study Of Homogeneous Nucleation Of Water Vapor In Helium, Raymond J. Schmitt
Masters Theses
"Absolute homogeneous nucleation rates in a supersaturated mixture of water vapor and helium are measured using a long sensitive time expansion chamber and a method devised by Kassner and Allard. A pulse technique is employed to produce the nucleation in an effort to suppress disturbing influences of vapor depletion and droplet growth. The time-varying nature of the supersaturation during the nucleation pulse is taken into account by an Integration over the pulse. Observed and theoretically predicted droplet concentrations are related by an assumed nucleation rate law which is adjusted until the total droplet populations predicted by integration of the assumed …
A Terrain Study Of The Bloodland Quadrangle, Pulaski County, Missouri, Lawrence E. Mullins
A Terrain Study Of The Bloodland Quadrangle, Pulaski County, Missouri, Lawrence E. Mullins
Masters Theses
"This study is an investigation of the environmental conditions which affect cross country movement for tracked military vehicles on a major portion of the Fort Leonard Wood Military Reservation.
The terrain has been mapped from the trafficability standpoint by an investigation of the geology, topography, pedology and restrictive vegetation characteristics of the Bloodland seven and one-half minute quadrangle. The terrain analysis was accomplished by a combination of map study, laboratory investigation, photo interpretation, and direct field study of representative soil and vegetation types. The conclusions of this analysis are presented in the form of a cross country movement map"--Abstract, page …
Linear And Quadratic Programming With More Than One Objective Function, William John Lodholz
Linear And Quadratic Programming With More Than One Objective Function, William John Lodholz
Masters Theses
"A computational procedure is presented for determining optimal solutions to the linear and quadratic programming problem when there is more than one objective function subject to linear constraints. In general a unique solution does not exist and a set of "best" or "efficient" points is determined and presented in graphical or tabular form. To solve the mathematical programming problems the simplex method is used for linear objective functions and Wolfe's method is used for quadratic objective functions"--Abstract, page ii.
I. An Investigation Of The Organic Compounds In The Media And Mycelium Of Naucoria Confragosa. Ii. Study Of The Extra-Cellular Pigments Of An Unknown Fungus, Yueh-Tsun Chen
Masters Theses
"The fungal metabolites excreted into the culture fluid by basidiomycetes growing on synthetic glucose media as well as formed in the mycelia of the organisms were investigated in this thesis. Earlier unpublished work had shown that Maucoria confragosa excreted into the medium compounds which were thought to be phenols. Insufficient material was recovered from an ethyl acetate extract of the medium in the present study for further investigation. Colorimetric methods were employed both for the quantitative estimation of reducing sugar not consumed by the microorganisms as well as for a measure of the total organic solids present in the spent …
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Masters Theses
"The 'Old Workings Area,' so called for its early mining by the Incas, is located 4 1/2 miles northeast of the El Salvador Porphyry copper deposit, the third largest copper producer in Chile. The area mapped in this study is shown to consist of rhyolite pebble conglomerate, two volcanic flows, andesite and rhyolite porphyry, and two intrusions. Quartz porphyry and tourmaline-bearing breccia. Petrographic study of surface and drill core rock samples confirms the field nomenclature used for the five rock types. All of the rock types are altered, but the quartz porphyry and andesite are the most intensely altered. Both …
Tschebyscheff Fitting With Polynomials And Nonlinear Functions, George F. Luffel
Tschebyscheff Fitting With Polynomials And Nonlinear Functions, George F. Luffel
Masters Theses
"It is the purpose of this study to survey the properties of the Tschebyscheff polynomials with particular reference to how they are employed as approximants and interpolants. The survey is extended to include the process known as "Tschebyscheff Approximation" or "Tschebyscheff Fitting" of a function by functions other than polynomials. One such fitting technique which will be of particular interest in this study is that of fitting f(x) by the function abx + c where a, b, c are real and b ≠ 1. In addition to a survey of the properties of the Tschebyscheff polynomials and of Tschebyscheff …
Geology Of Cienega Mining District, Northwestern Yuma County, Arizona, Elias Zambrano
Geology Of Cienega Mining District, Northwestern Yuma County, Arizona, Elias Zambrano
Masters Theses
"The purpose of this investigation was to determine the general geology of an unusually complex area containing several small mines and located in the northwest corner of Yuma County, Arizona. This report is the first attempt to work out in detail the lithology, structure, stratigraphy, petrography, and economic geology of the area"--Introduction, Purpose and Scope, page 1.
Investigations Of Neutron Collimators And Detector Systems Used In A Neutron-Capture Internal-Conversion Apparatus, William Charles Johnston
Investigations Of Neutron Collimators And Detector Systems Used In A Neutron-Capture Internal-Conversion Apparatus, William Charles Johnston
Masters Theses
Preface
During the past six decades considerable effort has been devoted to investigating and explaining the phenomena associated with the atomic nucleus. However, many important features of the nucleus still are not understood. Among these are such fundamental aspects as the structural composition of the nucleus, the nature of the forces between nucleons, and several of the basic processes that occur among the nuclear constituents. The goal of nuclear physics is to construct a unified theory which is able to explain all nuclear phenomena.
The experimentalist contributes toward this objective by gathering and classifying extensive amounts of experimental data in …
Angular Correlation Of Co60, Henry Kuhlman
Angular Correlation Of Co60, Henry Kuhlman
Masters Theses
Chapter I
Introduction
The probability that a radioactive nucleus will emit a gama ray may depend on the angle between the nuclear spin axis and the direction of emission. The radiation pattern of a sample of randomly oriented nuclei is isotropic. An anisotropic pattern may be observed if the nuclear spin axes are aligned.
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
Masters Theses
Introduction
It has been shown that ketohydrazones react with lead tetraacetate to give azoacetates in good yields (11) according to the following equation:
R2C=N-NH-R + Pb(OAc)4 → R2C(OAc)-N=N-R + Pb(OAe)2 + HOAc
The reaction of the structurally related 4,4- disubstituted ketosemicarbazones with lead tetraacetate quite unexpectedly gave carbamates in good yields (10) presumably according to the following equation:
R2C=N-NH-Co-NR2 + Pb(OAc)4 → R2C-O-CO-NR2 + N2 + Pb(OAc)2 + HOAc
CO
ı
CH3
A Measurement Of The Spin Relaxation Time Of Optically Pumped Rubidium Vapor, Robert Oliver Breault
A Measurement Of The Spin Relaxation Time Of Optically Pumped Rubidium Vapor, Robert Oliver Breault
Masters Theses
Chapter I
The Problem and Atomic Energy Levels
In 1949 Francis Bitter proposed a method for optcally detecting radio frequency resonance. That same year Alfred Kastler, Fcole Normale Superiéure, Paris, France, introduced a technique, which he called "Optical Pumping", of concentrating atoms in some of the Zeeman sublevels of one of the hyperfine state levels of the ground state. These two experiments are the basis of research involving optical methods of atomic orientation and of magnetic resonance.
Study Of The Ste. Genevieve Formation At Selected Localities In Southern Illinois And Western Kentucky, Mahlon Jack Apgar Reinhard
Study Of The Ste. Genevieve Formation At Selected Localities In Southern Illinois And Western Kentucky, Mahlon Jack Apgar Reinhard
Masters Theses
"The carbonate rocks of the Mississippian Ste. Genevieve Formation were studied megascopically in four quarries--Cave in Rock, Franklin, Three Rivers, and Fredonia Valley--within a small area of the Illinois-Kentucky fluorspar district and in a drill-core from the Cave in Rock Quarry. The rocks were studied microscopically in seventy-four thin sections prepared from samples from the quarries and the drill-core. The Ste. Genevieve Formation is typically an extremely oolitic, fragmentally fossiliferous limestone which is very light gray to white. The megascopic descriptions of the quarry exposures are presented as measured sections and columnar sections. A detailed log of the drill-core is …
An Investigation Of The Sensitized Fluorescence Of The Mercury-Sodium And The Cesium-Rubidium Systems., Joseph Edward Hueser
An Investigation Of The Sensitized Fluorescence Of The Mercury-Sodium And The Cesium-Rubidium Systems., Joseph Edward Hueser
Masters Theses
"The experimental apparatus and techniques used for the study of sensitized fluorescence are discussed. In this study both glass and metal absorption cells were employed. Included also is a discussion of the transitions which 11 occur in the mercury-sodium and the cesium-rubidium systems, which were the two systems investigated. Both photographic and photometric techniques were used as means of detecting the sensitized fluorescence. The actual experimental apparatus used are discussed together with conclusions to be drawn and recommendations to be made from the individual experiments. The purpose of the experiments was to better understand the energy exchange processes in a …
A Method To Give The Best Linear Combination Of Order Statistics To Estimate The Mean Of Any Symmetric Population, Robert M. Smith
A Method To Give The Best Linear Combination Of Order Statistics To Estimate The Mean Of Any Symmetric Population, Robert M. Smith
Masters Theses
“This paper gives a distribution for the ratio of two non-independent normally distributed random variables. The random variables involved are jointly distributed as the bivariate normal with means zero and variance- covariance matrix V.
The sample mean and one-half the sum of the smallest and largest sample observations from the symmetrically truncated Cauchy density function are compared as estimates of the mean of this density function. The reason for this comparison is to determine which of these two estimators gives the best estimate of the mean.
A method to empirically determine the best linear combination of order statistics for any …
Transverse Spin Relaxation Of Optically Pumped Rubidium., Robert Evans Hufft
Transverse Spin Relaxation Of Optically Pumped Rubidium., Robert Evans Hufft
Masters Theses
The study of the transverse spin relaxation of rubidium vapor is a continuation of the work done by Kenneth Steinbruegge1 and that in progress by John Martin2 at the University of Missouri at Rolla. The purpose of the experiment is to study the change of intensity of the transmitted pumping light at resonance in the longitudinal direction, and the observation of the high frequency modulation of a second "cross" beam of light perpendicular to the first. Under resonant conditions this "cross" beam will exhibit a phase coherence and a loss of phase coherence when parameters of the experiment …
The Reaction Of Ketosemicarbazones With Lead Tetraacetate, Thomas M. Davies
The Reaction Of Ketosemicarbazones With Lead Tetraacetate, Thomas M. Davies
Masters Theses
Introduction
It has been demonstrated that lead tetraacetate will oxidize ketohydrazones to azoacetates in good yields (11).
R2C=N-NH-R + Pb(OAc)4 ------> R2C(OAc)-N=N-R + Pb(OAc)2 + HOAc
Since ketosemicarbazones are structurally equivalent to ketohydrazones, it was thought that the reaction of ketosemicarbazones with lead tetraacetate would proceed in a similar manner. Originally the object of this research was to prepare a series of new azo compounds related to semicarbazones by lead tetraacetate oxidation.
Pachycereus Marginatus Alkaloids, John M. Brewer
Pachycereus Marginatus Alkaloids, John M. Brewer
Masters Theses
Introduction
Serturner's paper, 1817, "Morphis, a New Salt-forming Substance, and Meconic Acid, as the Chief Constituents of Opium", opened a new era of discovery in organic plant chemistry. His isolation of the first alkaloid was soon followed by the isolation or narcotine by Robiquet and strychnine by Pelletier and Caventou. These basic compounds were at first called vegetable alkalies, but were later renamed alkaloids, meaning alkali-like11.
Minimization Of Boolean Functions., Don Laroy Rogier
Minimization Of Boolean Functions., Don Laroy Rogier
Masters Theses
"A systematic computational procedure is presented for simplifying a Boolean function. The procedure is an extension of the methods presented by W. V. Quine and E. J. McCluskey. Jr. Specific attention is given to the combined use of linear programming and dominance arguments to find a minimum sum of products for large cyclic prime implicant tables"--Abstract, p. ii
A Study Of Stability Of Numerical Solution For Parabolic Partial Differential Equations., Tsang-Chi Huang
A Study Of Stability Of Numerical Solution For Parabolic Partial Differential Equations., Tsang-Chi Huang
Masters Theses
"Parabolic partial differential equations hold a very important position in science and technology since they are encountered frequently in the solution of diffusion and heat-conduction problems. Theoretically, it is possible to solve many of these equations by analytical methods, but the modern development of mathematics has revealed that there are numerous difficulties in obtaining the solution. Numerical solutions for most applied problems of a parabolic partial differential equation type are practically necessary, thus methods for numerical solution or approximate solution became more important. Since numerical results are required for most applied problems of a parabolic partial differential equation type a …
Structural And Magnetic Characteristics Of The Belton Anomaly, Cass County, Missouri, Nagib Chamon
Structural And Magnetic Characteristics Of The Belton Anomaly, Cass County, Missouri, Nagib Chamon
Masters Theses
"A vertical intensity magnetic survey of approximately 156 square miles in Cass County, central-west Missouri, revealed a broad circular anomaly whose magnetic relief exceeds 1000 gammas. Surface rocks are very gently inclined and are of Pennsylvanian age. Crystalline basement rocks are at a depth of approximately 2400 feet. Analysis of the data shows that the Belton anomaly consists of discontinuous smaller magnetic anomalies surrounding the central part of this broad anomaly. The central area of the Belton anomaly is occupied by a magnetic low. Analytical calculation showed that the source of the magnetic disturbance is at least 3650 feet below …
A Study Of The Effect Of The Crystal Orientation On The Internal Friction Of Magnesium Single Crystals., Robert Ray Nothdurft
A Study Of The Effect Of The Crystal Orientation On The Internal Friction Of Magnesium Single Crystals., Robert Ray Nothdurft
Masters Theses
"The method of growing, etching, and cutting magnesium single crystals is described in some detail. Ten single crystals of magnesium of different orientations were prepared and studied. The internal friction and relative Young’s modulus were measured for each specimen as a function of applied stress on a quartz composite oscillator. The effect of the orientation on the strain amplitude independent decrement, the strain amplitude dependent decrement and the ratio of the strain amplitude dependent decrement to the relative Young's modulus is compared to the theory of the pinned dislocation model of Granato and Lücke"--Abstract, p. ii
Aging Of The Dielectric Properties Of Some Perovskite Ceramics, Hector Troche-Maldonado
Aging Of The Dielectric Properties Of Some Perovskite Ceramics, Hector Troche-Maldonado
Masters Theses
"The effect of aging upon the dielectric constant and the dissipation factor were investigated for a number of lead titanate zirconate ceramics of varying composition. The ceramics investigated have a perovskite type structure. The materials chosen all have tetragonal symmetry at room temperature but are close in composition to materials of rhombohedral symmetry.
Empirical relations were determined for each specimen giving the rate of aging of the dielectric constant (K) and loss factor in terms of the frequency (f) and the elapsed time (t). The range of frequency was l kcps to l mcps; the range of elapsed time was …
Construction And Test Of Equipment For Use In Ultrasonic Pulse Echo Studies., Charles Joseph Reinheimer
Construction And Test Of Equipment For Use In Ultrasonic Pulse Echo Studies., Charles Joseph Reinheimer
Masters Theses
"An ultrasonic pulse generator was constructed with a variable pulse width ranging from 4 microseconds to 10 milliseconds and a repetition period varying from 15 milliseconds to 5 seconds. The oscillator had an almost continuous range from 500 kilocycles to 18 megacycles per second.
Its applicability in studies of internal friction of metals was demonstrated with a single crystal aluminum sample"-- Abstract, p. vi
Studies Of An Electrical Method For Generating Ultrasonic Waves, Yung-Yien Huang
Studies Of An Electrical Method For Generating Ultrasonic Waves, Yung-Yien Huang
Masters Theses
“Ultrasonic waves have proved very valuable in the observation of both the velocity and the absorption coefficient of sound in various media. From the velocity measurements of ultrasonic waves in metals, it is possible to obtain elastic constants, such as the compressibility, and the specific heat. Also, the observed attenuation depends greatly on the type and structure of the material. One of the widely used methods for investigation of the internal losses in solid state physics is the pulse-echo technique. This method is being used almost exclusively in internal friction investigation"--Introduction, page 1.