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Articles 1591 - 1620 of 2077
Full-Text Articles in Physical Sciences and Mathematics
Distribution, Petrology, And Environment Of The St. Louis-Ste. Genevieve Transition Zone In Missouri, Donald Howerton Fielding
Distribution, Petrology, And Environment Of The St. Louis-Ste. Genevieve Transition Zone In Missouri, Donald Howerton Fielding
Masters Theses
"In eastern Missouri, southeastern Iowa, and western Illinois - a transition zone, a body of rock consisting of several lithosomes which has a geographic extent measured in scores to hundreds of miles and which lies between a single overlying formation and a single underlying formation and which has lithologic and/or paleontologic properties common to both the overlying and the underlying formations, was found to exist between the St. Louis and the Ste. Genevieve formations. This transition zone is called the St. Louis-Ste. Genevieve Transition Zone, and is shown to possibly be due to continuous deposition between these two times and …
Inclusion Theorems For Boundary Value Problems For Delay Differential Equations, Leon M. Hall
Inclusion Theorems For Boundary Value Problems For Delay Differential Equations, Leon M. Hall
Masters Theses
"In this thesis existence and uniqueness of solutions to certain second and third order boundary value problems for delay differential equations is established. Sequences of upper and lower solutions similar to those used by Kovač and Savčenko are defined by means of an integral operator, and conditions are given under which these sequences converge monotonically from above and below to the unique solution of the problem. Some numerical examples for the second order case are presented. Existence and uniqueness is also proved for the case where the delay is a function of the solution as well as the independent variable"--Abstract, …
Mass Fraction And The Isotopic Anomalies Of Xenon And Krypton In Ordinary Chondrites, Edward W. Hennecke
Mass Fraction And The Isotopic Anomalies Of Xenon And Krypton In Ordinary Chondrites, Edward W. Hennecke
Masters Theses
"The abundance and isotopic composition of all noble gases are reported in the Wellman chondrite, and the abundance and isotopic composition of xenon and krypton are reported in the gases released by stepwise heating of the Tell and Scurry chondrites. Major changes in the isotopic composition of xenon result from the presence of radiogenic Xe¹²⁹ and from isotopic mass fractionation. The isotopic composition of trapped krypton in the different temperature fractions of the Tell and Scurry chondrites also shows the effect of isotopic fractionation, and there is a covariance in the isotopic composition of xenon with krypton in the manner …
The Oxidative Decarboxylation Of Aminopolycarboxylic Acids With Cerium (Iv) In Sulfuric Acid, Rita Kathleen Hessley
The Oxidative Decarboxylation Of Aminopolycarboxylic Acids With Cerium (Iv) In Sulfuric Acid, Rita Kathleen Hessley
Masters Theses
"The rates of oxidation of four chelating agents, NTA, EDTA CDTA, and DTPA with Ce(IV), in sulfuric acid media, were determined spectrophotometrically by a stopped-flow technique. The reductive ability is in the order CDTA>EDTA>DTPA>NTA. The influence of varying the acidity of the medium was studied, and in each case a maximum in the rate constant [H +] plot was observed. A possible interpretation of the reactivities and the influence of acidity is advanced"--Summary, page 1.
A Kinetic Study Of The Reductive Abilities Of Four Polyaminocarboxylic Acids (Edta, Cdta, Dtpa And Nta) Towards Cerium(Iv) In Perchloric Acid Media, Salem Ahmed Attiga
A Kinetic Study Of The Reductive Abilities Of Four Polyaminocarboxylic Acids (Edta, Cdta, Dtpa And Nta) Towards Cerium(Iv) In Perchloric Acid Media, Salem Ahmed Attiga
Masters Theses
"The reduction of Ce(IV) in HC10₄ solutions by four polyaminocarboxylic acids, which are commonly used as chelating agents, has been studied by the stopped-flow technique. The rates of reduction first increase with increasing acidity, reach maxima which are characteristic of the chelating agent and the medium, then progressively decrease with increasing the acid concentration in the media. At their maximum reactivities, trans-1,2-diaminocyclohexane tetraacetic acid (CDTA) shows the highest reductive ability; this is followed by ethylenedinitrilotetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and finally nitrilotriacetic acid (NTA). The observed maxima can be qualitatively explained in terms of a mechanism which involves unhydrolyzed …
Ground Water Of The Uncompahgre Valley Montrose County, Colorado, Ted William Craig
Ground Water Of The Uncompahgre Valley Montrose County, Colorado, Ted William Craig
Masters Theses
"Data from water quality tests of 50 wells and from general well information of 309 wells registered with the Colorado Division of Water Resources are presented for the area of Montrose County, Colorado, drained by the Uncompahgre River. This information, along with other pertinent information such as water laws and costs, is evaluated to determine the feasibility of increasing the use of ground water in the area. The drainage basin of the Uncompahgre River within the Montrose area bas three main geologic structures: the Uncompahgre uplift, the Montrose syncline, and the Gunnison uplift. All formations exposed in the area are …
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Masters Theses
"Permo-Pennsylvanian sedimentary rocks of the Minnelusa Formation of the Black Hills uplift, South Dakota and Wyoming, can be divided into upper, middle and lower divisions on the basis of lithology. The upper portion of 150 to 200 feet consists of gray and yellow sandstone, with some carbonates and shales in some sections. The middle portion, about 200 to 220 feet thick consists of gray and red sandstone with carbonate members including the prominent dolomite member at the base; some of the carbonates are cherty. The lower portion, 20 to 60 feet thick, consists of pink sandstone, arenaceous dolomite and thin …
Integrability Of The Sums Of The Trigonometric Series 1/2 Aₒ + ∞ [Over] Σ [Over] N=1 AN Cos Nθ And ∞ [Over] Σ [Over] N=1 AN Sin Nθ, John William Garrett
Integrability Of The Sums Of The Trigonometric Series 1/2 Aₒ + ∞ [Over] Σ [Over] N=1 AN Cos Nθ And ∞ [Over] Σ [Over] N=1 AN Sin Nθ, John William Garrett
Masters Theses
"The trigonometric series C = 1/2 aₒ + ∞ [over] Σ [over] [n=1] a[subscript n] cos nΘ and S = ∞ [over] Σ [over] n=1 a[subscript n] sin nΘ, where {a[subscript n]} monotonically decreases to zero both converge almost everywhere to functions f and g respectively. f (or g) is L iff C (or S) is the Fourier series of f (or g) iff term-by-term integration of C (or S) is valid. There are three equivalent conditions, each of which implies that C is the Fourier series of f...."--Abstract, page ii.
Hydrothermal Alteration Of Ash-Flow Tuffs In The Indian Peak District Of Southwestern Utah, Michael Allan Tolley
Hydrothermal Alteration Of Ash-Flow Tuffs In The Indian Peak District Of Southwestern Utah, Michael Allan Tolley
Masters Theses
"Careful petrographic study of the ash-flow tuffs in the Indian Peak District of southwestern Utah reveals hydrothermal alteration around the fluorite veins. The alteration minerals themselves and the intensity of alteration vary with distance from the veins. Primary plagioclase has altered to secondary feldspar, calcite, sericite, and traces of epidote and zoisite. Hornblende and biotite have altered to chlorite, calcite, and secondary iron oxide, and traces of epidote and zoisite. Diopside has changed to calcite and secondary iron oxide. An overall picture of the mining district shows that certain minerals increase and others decrease as one nears the veins. Hydrothermal …
Dolomitized Pahasapa Limestone (Mississippian), Northeastern Sector Of The Black Hills, South Dakota, Petrography And Geological Setting, Abdullatif Najjar
Dolomitized Pahasapa Limestone (Mississippian), Northeastern Sector Of The Black Hills, South Dakota, Petrography And Geological Setting, Abdullatif Najjar
Masters Theses
"The carbonates of the Mississippian Pahasapa Limestone in the northeastern sector of the Black Hills outcrops were examined in order to ascertain specific characters of the lithology in this area where the formation is predominantly a dolomite in contrast to adjacent areas where it is mainly a limestone. The Pahasapa seems to be uniform in thickness at the study areas and maintains a thickness of about 550 feet. Because of poor exposures, usually at the base or top, complete sections could not be measured. Much of the Pahasapa consists of coarsely crystalline dolomite containing varying proportions of crinoid plates, gastropods, …
Fossil Otoliths Of Some Lower Cenozoic Perciform Fishes Of The Gulf Coast, Mostafa Juma Salem
Fossil Otoliths Of Some Lower Cenozoic Perciform Fishes Of The Gulf Coast, Mostafa Juma Salem
Masters Theses
"Nineteen perciform species from the lower Cenozoic and one Recent species are described, and included under eight genera. The main characters that were considered as generic are the outline of the sagitta and the structure of the sulcus. The other features of the otolith were regarded as secondary in importance. The characters that were believed to be valuable at specific level are almost the same as those for the genus but in more detail. These species are considered to be within the Suborder Percoidei. The fossil species of "Nemipterus" were put in the Family Nemipteridae as they resembled the Recent …
A Measurement Of The Capture Coefficient And Of The Vapor Pressure Of Co₂ From 69ºk To 80ºk, Michel Louis Chouarain
A Measurement Of The Capture Coefficient And Of The Vapor Pressure Of Co₂ From 69ºk To 80ºk, Michel Louis Chouarain
Masters Theses
"The capture coefficient of CO₂ gas at 135ºK on a surface of CO₂ at temperatures between 69ºK and 80ºK is measured by means of quartz crystal microbalances. The vapor pressure of CO₂ is measured in the same range of temperature"--Abstract, page ii.
Tungsten Carbonyl Complexes Containing Positively Charged Phosphorus Ligands, Dilip Poonamchand Shah
Tungsten Carbonyl Complexes Containing Positively Charged Phosphorus Ligands, Dilip Poonamchand Shah
Masters Theses
Two positively charged complexes, (CO)5WP(C6H5)2CH2CH2-+P(C6H5)2(CH2C6H5) Br- and (CO)5W(C6H5)2PCH2+P(C6H5)2CH3 I-, were synthesized, and their carbonyl stretching frequencies and force constants were compared to those of the uncharged complexes, (CO)5WP(C6H5)2CH2CH2P(C6H5)2 and (CO)5WP(C6H5) …
Comparison Of Diffusion Coefficients Measured Electrochemically And Non-Electrochemically, Terry Dick Rotsch
Comparison Of Diffusion Coefficients Measured Electrochemically And Non-Electrochemically, Terry Dick Rotsch
Masters Theses
Diffusion coefficients of Co(en)3I3⋅H2O, FeCl3, and K3Fe(CN)6 were measured using the methods of polarography, chronopotentiometry, and diaphragm cell for the purpose of determining any relationships which may exist between these values. A major objective of the present study was to relate diffusion coefficients obtained by a simple non-electrotrochemical method to diffusion coefficients used in electrochemical techniques.
It was found that the polarographically determined diffusion coefficients were all 1.04 times larger than the chronopotentiometric values. This constant factor is probably due to viscosity differences tn the polarographic and chronopotentiometric solutions …
Studies In The Preparation Of Metal Enolates Of 3,3,5,5-Tetramethylcyclohexanone And Their Reactions With Lead(Iv) And Mercury(Ii) Acetates, Donald Robert Paveska
Studies In The Preparation Of Metal Enolates Of 3,3,5,5-Tetramethylcyclohexanone And Their Reactions With Lead(Iv) And Mercury(Ii) Acetates, Donald Robert Paveska
Masters Theses
No abstract provided.
A Comparative Limnological Study Of Three East Central Illinois Farm Ponds, Charles W. Furrey
A Comparative Limnological Study Of Three East Central Illinois Farm Ponds, Charles W. Furrey
Masters Theses
A comparative limnological study was conducted at three east central Illinois farm ponds between March 15 and September 18, 1970, to determine the incidence of nitrogen and phosphorus in the ponds resulting from agricultural sources. All ponds had corn, soybean, winter wheat cropping systems on their watersheds. Corn accounted for the greatest fertilizer application. One pond had significant numbers of livestock on its watershed that contributed high amounts of nitrogen and phosphorus to its waters. Limnological parameters measured at the surface, mid depth, and bottom of a ten foot water column in each pond were water temperature, dissolved oxygen, carbon …
The Halogen And Uranium Content Of Sedimentary Rocks, Tektites, Impact Glasses, And Obsidians, Victor J. Becker Jr.
The Halogen And Uranium Content Of Sedimentary Rocks, Tektites, Impact Glasses, And Obsidians, Victor J. Becker Jr.
Masters Theses
"The iodine and uranium concentrations in sedimentary rocks were measured by irradiating the samples in a neutron flux, radiochemically separating iodine, and ß-counting the resulting activity. The values obtained for uranium are in good agreement with previous estimates of the uranium content in sedimentary rocks. The values obtained for iodine define a distribution pattern similar to that reported for chlorine and bromine, in contrast with the distribution pattern previously reported for iodine in sedimentary rocks. The concentrations of chlorine, bromine, iodine and uranium were determined in tektites, obsidians and impact glasses by neutron activation. The uranium content found in tektites …
Freshwater Losses To The Sea And Water Level Decline In Northwest Libya, Mohammed Ahmed Attiga
Freshwater Losses To The Sea And Water Level Decline In Northwest Libya, Mohammed Ahmed Attiga
Masters Theses
"The area studied in this investigation, located in Tripolitania, Libya, between 13º and 16º east longitude and 31º and 33º north latitude, covers about 42,000 square kilometers. It is divided topographically into two parts. They are the coastal zone to the north and the Jebel (plateau) zone to the south. Some wadis which rise in the Jebel drain northward across the area to the sea. The temperature in the area ranges from 5ºC to 19ºC in the winter and from 19ºC to 40ºC in the summer. Precipitation in the area ranges from 380 millimeters to less than 100 millimeters. The …
Thermal Expansivity And Refractive Index Determinations For Some Hydrosol Systems And Their Similarity To Properties Ascribed To "Anomalous" Water, Gerald Wayne Chappue
Thermal Expansivity And Refractive Index Determinations For Some Hydrosol Systems And Their Similarity To Properties Ascribed To "Anomalous" Water, Gerald Wayne Chappue
Masters Theses
"The characteristic thermal expansion and refractive index of aqueous dispersions of SiO₂ and NaOH were determined for samples contained in quartz micro-capillaries. Comparison is made with the expansivity and refractive properties of anomalous water or polywater as reported by other investigators. The similarity between the properties and behavior of various hydrosol systems and those ascribed to anomalous water is cited as a serious challenge to the hypothesized existence of an allotropic modification of water"--Abstract, page ii.
Petrology And Petrography Of The Croweburg Coal, North-Central Missouri, William Keith Wedge
Petrology And Petrography Of The Croweburg Coal, North-Central Missouri, William Keith Wedge
Masters Theses
"Under a grant from the National Air Pollution Control Administration, the Missouri Geological Survey undertook a core drilling program of coals in north-central Missouri. The chemical and petrographic characteristics of five complete samples of the Croweburg coal recovered from this drilling project are major contributions of this study. Detailed lithologic logs of the drill cores are an additional contribution of the investigation. Megascopic lithotypes of vitrain, fusain, clarain, and durain as well as areas of mineral matter are described from polished column samples of the Croweburg coal for the first time in Missouri. Measured Croweburg coal sections from five drill …
Cobalt(Iii) Complexes With 1,2-Propanediaminediacetic Acid, Paul John Magnell
Cobalt(Iii) Complexes With 1,2-Propanediaminediacetic Acid, Paul John Magnell
Masters Theses
Introduction
Aminocarboxylic acid cobalt(III) complexes have been of interest to inorganic chemists since 1909 when Ley and Winkler isolated violet and rose colored geometric isomers of tris amino acid complexes of glycine and alanine.1 More recently, considerable interest has been shown in the study of the stereochemistry and optical activity arising from configurational and vicinal interactions of these complexes. Nuclear magnetic resonance of the methylene protons on the carboxylate portion of the coordinated ligand has also been studied.
Of immediate interest to this study is the stereo-chemistry of complexes containing flexible tetradentate ligands. A tetradentate ligand may be constructed …
Synthesis And Structure Proof Of Cis-6,6-Dichloro-2-Diphenylmethylene- Bicyclo [3.2.0] Hept-3-Ene-7-One And Cis-2,2- Dichloro- 1,2,2a,7a-Tetrahydro- 7-Diphenylmethylene-Cyclobut (A) Inden-1-0ne, William Douglas Barta
Synthesis And Structure Proof Of Cis-6,6-Dichloro-2-Diphenylmethylene- Bicyclo [3.2.0] Hept-3-Ene-7-One And Cis-2,2- Dichloro- 1,2,2a,7a-Tetrahydro- 7-Diphenylmethylene-Cyclobut (A) Inden-1-0ne, William Douglas Barta
Masters Theses
Introduction
The purpose of this research endeavor was to determine the structures of the adducts of dichloroketene with diphenylfulvene and benzodiphenylfulvene. Structure elucidation was attempted by chemical degradation and nmr analysis.
The structures of the adducts of dichloroketene with cyclopentadiene1,2 and indene3,4 have been determined by previous workers. The influence of the exocyclic double bond on the mode of cycloaddition is unknown.
The Reaction Of Ethylenediamine With Tetradentate Cobalt(Iii) Complexes, Laura H. C. Huang
The Reaction Of Ethylenediamine With Tetradentate Cobalt(Iii) Complexes, Laura H. C. Huang
Masters Theses
No abstract provided.
Small Angle Elastic Scattering Of 1.33 Mev Photons From Lead, Chwan-Kang Chiang
Small Angle Elastic Scattering Of 1.33 Mev Photons From Lead, Chwan-Kang Chiang
Masters Theses
No abstract provided.
The Design, Construction, And Application Of A Multibeam Fiber Optics Photometric Titrator, Marlin George Bensinger
The Design, Construction, And Application Of A Multibeam Fiber Optics Photometric Titrator, Marlin George Bensinger
Masters Theses
No abstract provided.
Elastic Scattering Of 1.33 Mev Gamma Rays From Uranium, Joan Sue De Vries
Elastic Scattering Of 1.33 Mev Gamma Rays From Uranium, Joan Sue De Vries
Masters Theses
No abstract provided.
The Stepwise Nature Of The Unwrapping And Transfer Of Ethylenediaminediacetate From Nickel(Ii) To Copper(Ii), Robert Swann
The Stepwise Nature Of The Unwrapping And Transfer Of Ethylenediaminediacetate From Nickel(Ii) To Copper(Ii), Robert Swann
Masters Theses
No abstract provided.
A Direct Measurement Of The Ratio Of The Reaction Cross Sections For Two-Photon And Three-Photon Annihilation Of A Positron And An Electron In Aluminum, Jeffrey Ira Siegel
A Direct Measurement Of The Ratio Of The Reaction Cross Sections For Two-Photon And Three-Photon Annihilation Of A Positron And An Electron In Aluminum, Jeffrey Ira Siegel
Masters Theses
No abstract provided.
A Study Of Defects In Platinum Using Positron Annihilation, Clarence D. Esseltine
A Study Of Defects In Platinum Using Positron Annihilation, Clarence D. Esseltine
Masters Theses
No abstract provided.
The Dipole Moment Of Cis- And Trans- Chloroiodoethylene, Ashvin Gajendralal Gajjar
The Dipole Moment Of Cis- And Trans- Chloroiodoethylene, Ashvin Gajendralal Gajjar
Masters Theses
No abstract provided.