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Articles 287251 - 287280 of 292849
Full-Text Articles in Physical Sciences and Mathematics
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 …
The Geology Of The Eldorado Mining District, Clark County, Nevada, Spenst M. Hansen
The Geology Of The Eldorado Mining District, Clark County, Nevada, Spenst M. Hansen
Doctoral Dissertations
The rocks of the Eldorado mining district, Clark County, Nevada, are of Precambrian, Tertiary and Quaternary age. Precambrian rocks include a heterogeneous series of gneisses and schists, younger garnetiferous granite gneiss and a youngest group of pegmatites. Paleozoic and Mesozoic rocks present in surrounding areas are absent in the district and Tertiary volcanics lie directly on the Pre- cambrian basement. Tertiary rocks consist of middle to late Tertiary flows and pyroclastic beds of andesite, basalt and rhyolite. These are assigned to three volcanic formations: the Patsy Mine volcanics; the Golden Door volcanics; and the Mount Davis volcanics. The Patsy Mine …
Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni
Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni
Doctoral Dissertations
"A review of the literature pertaining to the mineral paragenesis and trace element distribution in the Tri-State zinc-lead district of Missouri, Kansas, and Oklahoma revealed inconsistencies in observation and in interpretation and divergent hypotheses regarding the origin of the ores. In an attempt to reconcile the data collected by many investigators over nearly three-quarters of a century, the writer observed working faces in 37 mines, collected over 2,000 specimens for binocular examination and prepared and studied 110 polished surfaces and 60 thin sections of the ores and associated rocks utilizing mineralographic, petrographic, and x-ray techniques. This detailed study resulted in …
Glacial Geology Of Northern Logan County, South-Central North Dakota, Lee Clayton
Glacial Geology Of Northern Logan County, South-Central North Dakota, Lee Clayton
Theses and Dissertations
Northern Logan County, in south-central North Dakota, is included in two physiogeographic divisions: the southwest fifth is part of the glaciated Missouri Plateau that has integrated drainage and thin drift, and the rest is part of the Missouri Coteau, which has thick drift and nonintegrated drainage. Logan County is underlain by the Cretaceous Pierre Shale, undifferentiated Cretaceous sand, sandstone, and mudstone, and by three surface drifts, the Napoleon (lower part of the Wisconsin Stage), the Long Lake, and the Burnstad (upper part of the Wisconsin Stage) Drifts.
Landforms of the area southwest of the Coteau include ground moraine, outwash plains, …
The Micropaleontology And Stratigraphy Of The Subsurface "Heath" Formation (Mississippian-Pennsylvanian) Of Western North Dakota, Harold C. Ziebarth
The Micropaleontology And Stratigraphy Of The Subsurface "Heath" Formation (Mississippian-Pennsylvanian) Of Western North Dakota, Harold C. Ziebarth
Theses and Dissertations
The thesis here abstracted was written under the direction of F. D. Holland, Jr., and approved by Wilson M. Laird and Walter L. Moore as members of the examining committee, of which Dr. Holland was chairman.
The “Heath” Formation, between the underlying Otter and the overlying Amsden(?) Formations in the subsurface of southwestern North Dakota, is a source of petroleum in the Scoria-Fryburg, Rocky Ridge and Dickinson oil fields. Cores, cut from the interval under study, of twenty wells in this area, were the source of fossil and lithologic samples studied. Changes in lithology in these cores compared with changes …
Foraminiferida From Outcrops Of The Niobrara Shale (Upper Cretaceous) Of North Dakota, Kent A. Madenwald
Foraminiferida From Outcrops Of The Niobrara Shale (Upper Cretaceous) Of North Dakota, Kent A. Madenwald
Theses and Dissertations
Microfossils were obtained from outcrop samples of the Niobrara Formation in northeastern North Dakota and from subsurface samples in southeastern North Dakota. Ninety-three species of foraminiferids, of which two are new and eight others of uncertain assignment, are described and figured. One species previously reported from the Oligocene and Niocene of Trinidad and two species from the Lower Oligocene and Niocene of Antigua, B. W. I., were collected and described which extend the range of those species down to the Upper Cretaceous. The major portion of the fauna described is correlative with previously described faunas from Nebraska, Kansas and South …
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 …
Study Of The Copper-Uranium Deposits At Vilcabamba, Department Of Cuzco, Peru, Oscar Aguilar
Study Of The Copper-Uranium Deposits At Vilcabamba, Department Of Cuzco, Peru, Oscar Aguilar
Masters Theses
"Uranium has been known in the Vilcabamba district of Cuzco, Peru since 1954. Copper ores of high silver content were worked by the Spaniards during the seventeenth and the early eighteenth centuries, At the beginning of the twentieth century these ores were worked intermittently; during the last fifty years no mining operation has been going on.
The oldest rocks in the thesis area consist of Ordovician phyllites. The presence of Devonian in the area is questionable, but has been recognized 5 km. away from the thesis area. A conglomerate of limited lateral extent of Mississippian age overlies the Devonian (?) …
Shear And Tension Fracture Patterns Of Northwest Arkansas, John F. Gibbons
Shear And Tension Fracture Patterns Of Northwest Arkansas, John F. Gibbons
Journal of the Arkansas Academy of Science
No abstract provided.
Geological Implications Of Soil Mechanics, James Harrison Quinn
Geological Implications Of Soil Mechanics, James Harrison Quinn
Journal of the Arkansas Academy of Science
No abstract provided.
A Matrix Formulation Of The Least-Squares Method And Its Application To Nuclear Decay Schemes, Otto Harry Otteson
A Matrix Formulation Of The Least-Squares Method And Its Application To Nuclear Decay Schemes, Otto Harry Otteson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Many people call physics an ''exact science". This may be true depending on our definition of exact. Most dictionaries include as a definition of exact the words "strictly accurate". The average man thinks of an "exact science" as one which yields "strictly accurate'' results. Physics then is exact only to a degree.
Petrography Of The Midale Subinterval In The Bottineau And Renville Counties Area, North Dakota, Morris J. Mccollum
Petrography Of The Midale Subinterval In The Bottineau And Renville Counties Area, North Dakota, Morris J. Mccollum
Theses and Dissertations
About 250 thin sections of core samples from the Midale subinterval in the Bottineau-Renville Counties area of North Dakota (T161N-T164N and R78W-R86W) were studied petrographically. The Midale subinterval is the basal section of the Ratcliffe interval of the Madison Group of Mississippian age. In the area of study it is composed of interbedded fine grained limestones, pelletiferous and oolitic limestones, and primary anhydrite. Dolomitization of the limestones in varying stages is common and the dolomitized limestones are usually fine grained. Course crystals of secondary anhydrite are common as vug and fracture filling and as a replacement of the carbonates.
The …
Glass-To-Sapphire End Window Seals, Edward E. Stepp, Richard A. Anderson
Glass-To-Sapphire End Window Seals, Edward E. Stepp, Richard A. Anderson
Physics Faculty Research & Creative Works
SAPPHIRE windows have been used in laboratory devices where radiation from the ultraviolet through the infrared must be transmitted. Sapphire windows have been valuable in chambers which contain the alkali metals, for the alkali metals are known to react with Pyrex 7740 glass and quartz leaving them pitted and darkened. This paper is a report on an improved glass-to-sapphire end window seal.
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 …
The Dielectric Strength Of Some Anti-Corrosive Paints, George Albert Chappell Iii
The Dielectric Strength Of Some Anti-Corrosive Paints, George Albert Chappell Iii
Masters Theses
"Corrosion has been one of the costly problems to industry because each year losses due to corrosion are in excess of six billion dollars. Corrosion is caused by the tendency of all metals to become oxidized and return to their natural state. Oxidation may be suppressed by restraining the flow of electrons from the system, thereby inhibiting corrosion.
One effective means to prevent rusting is by applying a barrier of paint between the system and the corrosive atmosphere. Not all paints, however, are equally effective as corrosion inhibitors. At present, the only effective means of determining the corrosion resistant ability …
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 …
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 …
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 …
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."
A Study Of The Colloidal Properties Of Zirconium And Promethium By Electrodialysis And Liquid-Liquid Extraction, James N. Click
A Study Of The Colloidal Properties Of Zirconium And Promethium By Electrodialysis And Liquid-Liquid Extraction, James N. Click
Masters Theses
"The purpose of this investigation was to study the solution chemistry of zirconium by investigating the colloidal behavior of natural zirconium and zirconium-95, utilizing electrodialysis and liquid-liquid extraction techniques. Also incorporated into this study was the investigation of optimum conditions for the extraction of the natural zirconium and zirconium-95 with thenoyl trifluoracetone. A limited amount of work was done on the colloidal nature of promethium-147"--Introduction, pages 2-3.
Investigation And Development Of Ground Water Of Chalone Creek, (Pinnacles National Monument, California), Donald Lee Brown
Investigation And Development Of Ground Water Of Chalone Creek, (Pinnacles National Monument, California), Donald Lee Brown
Masters Theses
"The Pinnacles National Monument is located in San Benito and Monterey Counties about 130 highway miles south of San Francisco, California. Because of unusual patterns in volcanic rocks, the Monument was set aside as a recreation area on January 16, 1908, by President Theodore Roosevelt. It encompasses an area of approximately 12,818 acres.
Water quality and supply problems were experienced at the Monument in the few years prior to 1961. In 1961, a collection trench system was installed to alleviate the water supply condition. A horizontal trench system, 215 feet long and four feet below the dry season water table, …
Chemistry Of Chesapeake Bay Sediments, David Kenneth Young
Chemistry Of Chesapeake Bay Sediments, David Kenneth Young
Dissertations, Theses, and Masters Projects
No abstract provided.
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 …
"Invariant Imbedding" And Wave Propagation In Inhomogeneous Media, Crawford J. Maccallum
"Invariant Imbedding" And Wave Propagation In Inhomogeneous Media, Crawford J. Maccallum
Physics & Astronomy ETDs
We wish now to address ourselves to that problem which can be described in physical terms as the reflection and transmission of "waves" by and through some sort of "transition region" between two homogeneous media. At this stage we will work strictly within one dimension; later on this severe restriction will be somewhat eased. For simplicity of notation we will for the present give the transition region a finite thickness h; later on we will often allow h to become infinite when the disturbance due to the transition region dies away fast enough with distance.
Flame Photometric Studies: Part A: Studies Of The Extraction And Flame Emission Of Yttrium; Part B: Droplet Size Of Aerosols In Flame Photometry; Part C: Studies Of The Reaction Zone Of An Oxygen Acetylene Flame, William Joseph Carnes
Doctoral Dissertations
Although the flame spectrum of yttrium has been well defined in previous work, very little information was available in regard to the effect of spectral and radiation interferences, other than the rare earths, upon the emission of yttrium. Information regarding the optimum conditions for the flame-photometric determination of yttrium was lacking also. The main objective of this phase of work was clarification of these points. Development of a suitable method of analysis for yttrium was also considered.
Some Reactions Of Phenothiazine And Certain Benzophenothiazines, John Charles Gilmer
Some Reactions Of Phenothiazine And Certain Benzophenothiazines, John Charles Gilmer
Doctoral Dissertations
Summary
The consideration of the medical importance of phenothiazine derivatives and the known cancer chemotherapeutic value of the nitrogen mustards made the synthesis of some nitrogen mustard derivatives of the phenothiazines of particular interest. In the course of this research the N-{2-[bis-(2-chloroethyl)amino]ethyl} derivatives of phenothiazine, 7H-benzo[c]phenothiazine, 7H-dibenzo[c, h] phenothiazine, and 14H-dibenzo[a, h] phenothiazine were synthesized for anticancer evaluation. Also submitted to the Cancer Chemotherapy National Service Center for testing were the N-(2-chloroethyl) monofunctional nitrogen mustard derivatives of the first three phenothiazines mentioned above.
Hyperfine Splitting In Aromatic Free Radicals, Juana Acrivos
Hyperfine Splitting In Aromatic Free Radicals, Juana Acrivos
Faculty Publications, Chemistry
No abstract provided.
Separation Of The N-Sphere By An (N - 1)-Sphere, James C. Cantrell
Separation Of The N-Sphere By An (N - 1)-Sphere, James C. Cantrell
Masters Theses
In this thesis we consider certain (n-1)-spheres embedded in S^n (we will frequently use the fact that S^n is topologically equivalent to the one point compactification of E^n). The problem is then to establish the existence or non-existence of certain topological properties of the two domains into which S^n is separated by the given (n-1)-spheres.
The Uniform Right Ideals Of A Ring Of Matrices, Gerald Joseph Janusz
The Uniform Right Ideals Of A Ring Of Matrices, Gerald Joseph Janusz
Bachelors’ Theses
The concept of uniform right ideals plays an important part in the structure tbeory of prime rings and semi-prime rings as developed by Goldie in [1] and (=[2]. Very few examples of uniform right ideals appear in the literature, however. In section one, we obtain the form of these right ideals in a matrix ring, In, where I is a right Ore domain with identity. The existence of the identity involves some loss of generality, but greatly simplifies the approach used in this paper.
Mining Activities In Turkey During 1961, - -
Mining Activities In Turkey During 1961, - -
Bulletin of the Mineral Research and Exploration
No abstract provided.