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Articles 288301 - 288330 of 291756
Full-Text Articles in Physical Sciences and Mathematics
A Necessary And Sufficient Condition That A Set Be Homeomorphic To A Plane Region Bounded By A Finite Number Of Nonintersecting Circles., Robert Lloyd Broussard
A Necessary And Sufficient Condition That A Set Be Homeomorphic To A Plane Region Bounded By A Finite Number Of Nonintersecting Circles., Robert Lloyd Broussard
LSU Historical Dissertations and Theses
No abstract provided.
Bridge Measurements Of The Equivalent Electrical Characteristics Of Selenium Rectifiers., Allan Walter Mcdonald
Bridge Measurements Of The Equivalent Electrical Characteristics Of Selenium Rectifiers., Allan Walter Mcdonald
LSU Historical Dissertations and Theses
No abstract provided.
Itaconic Acid Derivatives Of Sulfanilamide And Sulfone, Malcolm J. Thompson
Itaconic Acid Derivatives Of Sulfanilamide And Sulfone, Malcolm J. Thompson
Electronic Theses and Dissertations
This thesis, submitted to Xavier University in partial fulfillment of requirements for a Maters degree in chemistry in 1952, reports the synthesis and characterization of itaconic acid derivatives of sulfanilamide and amino phenyl sulfone compounds. The research describes reaction procedures and the isolation and purification of a series of novel chemical compounds, with experimental data including melting points, percent yields, elemental analysis, and molecular weights reported for numerous derivatives. The thesis presents conclusions regarding the chemical properties and reactivity of the synthesized compounds.
Note: No original abstract was included; this abstract is provided by the XULA Digital Commons editors.
Chalcones Derived From M-Nitroacetophenone, Richard Allan Hendry
Chalcones Derived From M-Nitroacetophenone, Richard Allan Hendry
University of the Pacific Theses and Dissertations
The object of this research was to prepare substituted derivatives of various chalcones having the nitro group substituted in the 31-position, the idea being to help complete the series of chalcones having the nitro group in that position. This was to be done by condensing various substituted benzaldehydes with m-nitroacetophenone, using dry hydrogen chloride as a condensing agent. The properties of the resulting chalcones were then to be determined by observing color reactions, spectra, and other general physical properties.
Urea Adducts Of The Esters Of Stearic Acid, Paul Elliott Greene
Urea Adducts Of The Esters Of Stearic Acid, Paul Elliott Greene
University of the Pacific Theses and Dissertations
Urea forms crystalline complexes with n-alkanes and their liner derivatives but not with most branched and cyclic hydrocarbons and their derivatives. The compounds are stable enough to be used in separating these types of aliphatic compounds from their branched and cyclic analogs. Linear esters derived from normal saturated acids give adducts as expected. Urea complexation was found to be of great importance in the purification and separation of unsaturated esters of high molecular weight.
The object of the present research was to investigate the compositions of urea adducts of various long-chain esters, approaching the class of waxes, to test various …
The Spieker Circle And Certain Related Configurations, Berthola Elmo Lumzy
The Spieker Circle And Certain Related Configurations, Berthola Elmo Lumzy
Electronic Theses and Dissertations
This thesis, presented to the Department of Mathematics at Xavier University in partial fulfillment of requirements for the degree of Master of Arts in 1952, examines the Spieker circle, a circle inscribed in the median triangle of a given triangle, and extends its defining properties to related geometric configurations. Lumzy first establishes a series of analogies between the Spieker circle and the nine-point circle, demonstrating parallel relationships involving radius, center, harmonic conjugates, and homothetic centers relative to the incenter, median point, and Nagel point of a triangle.
The thesis then proves that the Spieker circle is inscribed in two congruent …
A Critical Analysis Of Several Product And Factoring Formulas, Herbert Wills
A Critical Analysis Of Several Product And Factoring Formulas, Herbert Wills
Masters Theses
No abstract provided.
Aromatic Acetals : Their Synthesis And Alkylation, Robert Conner Gass
Aromatic Acetals : Their Synthesis And Alkylation, Robert Conner Gass
University of the Pacific Theses and Dissertations
The purpose of this investigation was to study the known methods of forming acetals and find one or several that could be used in further investigation. In connection with the reactions, the use of various catalysts was pertinent. Some of the catalysts used were hydrogen chloride, calcium chloride, ferric chloride, aromatic sulfonic acids, and other. There was no data available comparing the sulfonic acids with the inorganic salts and mineral acids. For that reason one of the subsidiary problems of this investigation was such a comparison.
In order to investigate stability, several acetals were subjected to conditions intended to produce …
Montan Wax From California Lignites, Robert John Kvick
Montan Wax From California Lignites, Robert John Kvick
University of the Pacific Theses and Dissertations
Montan wax has been extracted from the lignite deposits of Germany since the early part of the twentieth century, The wax was named by von Boyen (1901), The word Montan is derived from the Latin term montanus meaning "of a mountain," The wax has found extensive uses in polishes, insulating materials, candles, explosives, and special applications in the rubber industry, The increased demand for waxes for industrial uses and the limited supply of domestic origin has made the study of the sources and characteristics of domestic waxes desirable, California lignite has been shown to be a valuable source of Montan …
Tannin Content Of Certain California Oaks, Arthur Carton
Tannin Content Of Certain California Oaks, Arthur Carton
University of the Pacific Theses and Dissertations
The purpose of this paper is to investigate three California oaks as possible sources of tannin. Even though the study of the three varieties of tree may not be representative samples, the procedures developed may prove to be valuable in a more extensive research by other workers.
Geochemical Prospecting Applied To The Illinois-Kentucky Fluorspar Area, Matthew Peter Nackowski
Geochemical Prospecting Applied To The Illinois-Kentucky Fluorspar Area, Matthew Peter Nackowski
Doctoral Dissertations
"This study was completed to determine whether geochemical methods of prospecting could be applied to the search for fluorspar deposits in the Illinois-Kentucky fluorspar district.
During the course of the study, aspects of the geochemical cycle of fluorine under the climatic environment encountered were noted in the zone of weathering.
The Illinois-Kentucky fluorspar district supplies a large portion of the fluorite consumed in the United States. The producing deposits are of two geologic types. The vein deposits occur as nearly vertical tabular lenses or pods which occupy fractures. These deposits may reach the bedrock surface, but in any case, the …
The Expansion Of A Single-Valued Function Of Several Variables Having For Its Rangeadenumerable Set Of Real Numbers And For Its Domain Of Definitionaset Of Real Numbers, Nicholas Christ Scholomiti
The Expansion Of A Single-Valued Function Of Several Variables Having For Its Rangeadenumerable Set Of Real Numbers And For Its Domain Of Definitionaset Of Real Numbers, Nicholas Christ Scholomiti
Master's Theses
No abstract provided.
A New Basic Copper Phosphate Mineral From Santa Rita, New Mexico, David B. Givens
A New Basic Copper Phosphate Mineral From Santa Rita, New Mexico, David B. Givens
Earth and Planetary Sciences ETDs
Supergene minerals are not common, nor are they rare at Santa Rita, New Mexico. Kerr (1950,307) reports the presence of cuprite, melaconite, native copper, chrysocolla, machite and azurite. There is also smithsonite present.
The physical appearance of the mineral, coupled with preliminary determinations of the indices of refraction, gave a rough correspondence with dihydrite (Larson and Berman, 1934, 135). However, enough discrepancy existed to warrant taking powder and Weissenberg X-Ray pictures. From these it was evident immediately that the specimen was a new mineral species.
The Monadnock Volume 26, Number 1, December 1951, Clark University Geographical Society
The Monadnock Volume 26, Number 1, December 1951, Clark University Geographical Society
The Monadnock (Clark Geographical Society)
Volume 26, Issue 1 of The Monadnock. The Monadnock was the alumni magazine of the Clark University Geographical Society (1927-1985) (2014-present).
The Red Cloud Sand And Gravel, A New Pleistocene Formation In Nebraska, C. Bertrand Schultz, Eugene C. Reed, A. L. Lugn
The Red Cloud Sand And Gravel, A New Pleistocene Formation In Nebraska, C. Bertrand Schultz, Eugene C. Reed, A. L. Lugn
Conservation and Survey Division: Faculty and Staff Publications
Recent studies of the stratigraphy and paleontology of the Pleistocene of Nebraska have resulted in additional data that require further clarification and partial revision of the Grand Island sand and gravel formation (1,2) in order that there may be no condusion as the results of varying usage of the term.
Nttl Engine Test 2 Petter Av2 Diesel Engine, Nebraska Tractor Test Lab
Nttl Engine Test 2 Petter Av2 Diesel Engine, Nebraska Tractor Test Lab
Nebraska Tractor Tests
No abstract provided.
Engine Test 1 Petter Ava2 Diesel, Nebraska Tractor Test Lab
Engine Test 1 Petter Ava2 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
No abstract provided.
Odor Report (1951), Walter A. Lawrance
Supplement To Odor Report (1951), Walter A. Lawrance
Supplement To Odor Report (1951), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Addition Of Sodium Nitrate (1951), Walter A. Lawrance
Addition Of Sodium Nitrate (1951), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Press Reports (1951), Walter A. Lawrance
Analytical Data (1951), Walter A. Lawrance
Analytical Data (1951), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
The Red Cloud Sand And Gravel, A New Pleistocene Formation In Nebraska, C. Bertrand Schultz, Eugene C. Reed, Alvin Leonard Lugn
The Red Cloud Sand And Gravel, A New Pleistocene Formation In Nebraska, C. Bertrand Schultz, Eugene C. Reed, Alvin Leonard Lugn
Department of Earth and Atmospheric Sciences: Faculty Publications
Recent studies of the stratigraphy and paleontology of the Pleistocene of Nebraska have resulted in additional data that require further clarification and partial revision of the Grand Island sand and gravel formation (1,2) in order that there may be no confusion as the result of varying usage of the term.
The Nebraska Geological Survey, the University of Nebraska State Museum, and the Department of Geology at the University of Nebraska have approved the foregoing restriction of the term Grand Island and the adoption of the new name Red Cloud sand and gravel, and these names will be used in future …
Test. 469: Minneapolis-Moline Bf, Nebraska Tractor Test Lab
Test. 469: Minneapolis-Moline Bf, Nebraska Tractor Test Lab
Nebraska Tractor Tests
No abstract provided.
Investigation Of Penetrating Cosmic-Ray Showers In Water, George William Rollosson
Investigation Of Penetrating Cosmic-Ray Showers In Water, George William Rollosson
Physics & Astronomy ETDs
In this investigation, some of the properties of the radiation which produces penetrating showers in its passage through matter are studied. Geiger techniques are used to measure the average distance over which the neutral radiation produces one penetrating shower. This distance, called collision length, is measured in water...
The collision length, on the other hand, is measured by placing the material near the apparatus and measuring the mean distance in which one shower is produced and eliminating from the observation any penetrating showers which may be produced subsequently either (a) by the original particle or (b) by the secondaries from …
An Experimental Investigation Of The Dead Time Of Geiger-Mueller Counters, Peter H. Jessner
An Experimental Investigation Of The Dead Time Of Geiger-Mueller Counters, Peter H. Jessner
Physics & Astronomy ETDs
As ever more sensitive and precise experiments are being performed with Geiger Counters, especially in cosmic ray research, the resolving power of these instruments assumes an ever increasing importance. With the present perfection of electronic circuitry, this resolving time has become largely a function of the dead time of the Geiger counter tube itself. It was therefore proposed to investigate methods of reducing this dead time. Only self-quenching counter tubes had to be considered in this connection since the dead time of all other types of Geiger counters is inherently longer.
A Sensitive Electronic Photometer Employing Negative Feedback, John Lee Pack
A Sensitive Electronic Photometer Employing Negative Feedback, John Lee Pack
Physics & Astronomy ETDs
Purpose of the Instrument
The instrument to be described in these pages was tentatively intended to be used for the purpose of scanning the night sky automatically for investigations of the zodiacal light. It was to detect light below the noise level of a photomultiplier tube, to have linearity up to signals 100 times greater than the noise level, and to have a response time of about 10-4 seconds.
The Elastic Scattering Of Deuterons By Deuterons, Richard John Runge
The Elastic Scattering Of Deuterons By Deuterons, Richard John Runge
Physics & Astronomy ETDs
The concern of this work is the calculation of elastic scattering of deuterons by deuterons. The solution of the problem will be given in the usual center of mass system of coordinates, the conversion of results from this to the laboratory system being standard. Since the deuteron itself consists of a neutron and a proton, the problem is thus one of four bodies. The nuclear three body problem of the scattering of a neutron by a deuteron has been treated by previous authors and we will have occasion to employ methods used by these authors extending them to the four …
Enrichment Of Tin Activity Through The Szilard-Chalmers Separation, Herta W. Spano
Enrichment Of Tin Activity Through The Szilard-Chalmers Separation, Herta W. Spano
Chemistry and Chemical Biology ETDs
It was the purpose of this investigation to utilize the Szilard-Chalmers reaction in order to prepare tin solutions of high specific activity.
Tetraphenyl tin was chosen for the target compound. It is a white, crystalline solid of excellent thermal stability. No data have been reported in the literature on the rate of exchange between inorganic forms of tin and tetraphenyl tin but it seemed highly probable that this exchange would be very slow. Tetraphenyl tin is soluble in various organic solvents but insoluble in water, and this suggested solvent extraction as a possible means of separation of the activated tin …
Radioactive Disintegration, Robert Katz
Radioactive Disintegration, Robert Katz
Robert Katz Publications
The conventional development of parent-daughter relationships in radioactive disintegration follows the treatment given in Rutherford, Chadwick, and Ellis in which a trial solution of the differential equations appropriate to the process is proposed, and the arbitrary constants are evaluated by application of boundary conditions. At the senior-graduate level at which the first course in nuclear physics is usually taught, the following derivation is believed to be considerably more instructive.