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Articles 286021 - 286050 of 293419
Full-Text Articles in Physical Sciences and Mathematics
A Theorem On Repeating Decimals, William G. Leavitt
A Theorem On Repeating Decimals, William G. Leavitt
Department of Mathematics: Faculty Publications
It is well known that a real number is rational if and only if its decimal expansion is a repeating decimal. For example, 2/7 = .285714285714 . . . . Many students also know that if n/m is a rational number reduced to lowest terms (that is, n and m relatively prime), then the number of repeated digits (we call this the length of period) depends only on m. Thus all fractions with denominator 7 have length of period 6. A sharp-eyed student may also notice that when the period (that is, the repeating digits) for 2/7 is split …
The Formation Of Tertiary Butyl Phenyl Ether By A Diazonium Salt Decomposition, Allan Richard Bernstein
The Formation Of Tertiary Butyl Phenyl Ether By A Diazonium Salt Decomposition, Allan Richard Bernstein
Honors Theses
Diarryl ethers have been prepared by various candidates for master's and bachelor's degrees at Union College in the past. Ulmann reactions were involved, but with some variability in yields and some rather lengthy syntheses. More recently, decompositions of diazonium salts have been studied for preparation of aryl ethers. This might constitute a simpler or more efficient synthetic route.
Rearrangements Of N-Nitrosolactams, Dennis Stuart Gordan
Rearrangements Of N-Nitrosolactams, Dennis Stuart Gordan
Honors Theses
The experiments reported here were done in an attempt to fill in the gap in Huisgen's work on N-nitrosolactams (1) - the synthesis and subsequent rearrangements of the six-membered-ring compounds of this type (I, ni2).
Synthesis And Absorption Spectra Of 2,4,6-Trihlorodiphenyl Ether, Dominic Louis Poccia
Synthesis And Absorption Spectra Of 2,4,6-Trihlorodiphenyl Ether, Dominic Louis Poccia
Honors Theses
The repeat of Schwab's work confirmed his experimental results for the reaction of the pseudo-hypochlorite of 2,4,6-trichlorophenol with benzene and anhydrous alumnium chloride.
An Attempt To Prepare Methyldiphenylsulfonium Fluoroborate, William Harvey Holley
An Attempt To Prepare Methyldiphenylsulfonium Fluoroborate, William Harvey Holley
Honors Theses
In the past few years there has been growing interest in two types of organic salts, those of sulfonium and oxysulfonium ions. Probably the better known are the sulfonium compounds. In general they are crystalline salts, and thet are water soluble giving neutral solutions. The trialkyl sulfoniym ion (fig. 1), like the quaetenary ammonium ion, has the tetrahedral structure except that in the sulfonium ion the fourth group is an unshared pair of electrons rather than a bonded group.
The Use Of Arsenic Trichloride As A Solvent In Nmr Spectrometry, Phillip Wills Haines
The Use Of Arsenic Trichloride As A Solvent In Nmr Spectrometry, Phillip Wills Haines
Honors Theses
Since Union College has had its Nuclear Magnetic Resonance Spectrometer, a great many organic compound have been analyzed. Several more might have been identified if they could have been dissolved in a suitable solvent. The expense of deuteratd solvents and the lack of suitable solvents for some compounds have led to the consideration of inorganic compounds for use as solvents.
The Hydroxylation Equilibrium Constant For 2,4 Dichlorobenzaldehyde At Various Temperatures, Gregory Richard Olson
The Hydroxylation Equilibrium Constant For 2,4 Dichlorobenzaldehyde At Various Temperatures, Gregory Richard Olson
Honors Theses
The primary objective of this work was to examine the temperature dependence of dissociation constants of hydroxylated substituted benzldehydes. The equilibrium of 2,3 dichlorobenzaldehyde in aqueos sodium hydroxide solutions has been studied at 35 degrees celsius with varying hydroxide ion concenctrations.
Metabolic Pathways For Methoxychlor In Rats, Frank Hastings Mckim
Metabolic Pathways For Methoxychlor In Rats, Frank Hastings Mckim
Honors Theses
The main approach of the experiment was to metabolize methoxychlor with rat liver microsomes since hepatic microsomes have been shown to contain many of the metabolic enzyme systems. The incubated sample was extracted with various solvents after hydrolysis. The extracts were separated and identified by thin layer or vapor phase chromatography. The structure of the metabolites were theoretically determined by studying the analogy between DDT and methoxychlor. A study of detoxification mechanisms also aided in establishing a theoretical metabolic chain.
Synthesis And Reactions Benzyldiazonium-2-Carboxylate, Marc David Rudich
Synthesis And Reactions Benzyldiazonium-2-Carboxylate, Marc David Rudich
Honors Theses
The purpose of this research is to investigate the reactions of benzyldiazonium-2-carboxylate or a precursor to determine whether they offer a pathway to the preparation of benzocyclopropene.
Synthesis Of 2-(2,5-Dichloro-Phenyl) Tetrahydro-3 Methyl 1-4-H-1, 3 Thiozone-4-One 1,1-Dioxide And Study Of The Sommelet Reaction Mechanism, Alexander James Wall Iii
Synthesis Of 2-(2,5-Dichloro-Phenyl) Tetrahydro-3 Methyl 1-4-H-1, 3 Thiozone-4-One 1,1-Dioxide And Study Of The Sommelet Reaction Mechanism, Alexander James Wall Iii
Honors Theses
The text of this thesis deals with two separate, but inter-related prob- lems. The first is the synthesis of 2-(2, 5-Dichloro-phenyl) Tetrahydro-3 methyl 1-4-H-l, 3 Thiozone-4-one 1, 1-Dioxide. The second is a study of the Sommelet reaction which was employed in the synthesis of the above compound. This project was undertaken to complete the synthesis of a group of analogous compounds which have been synthesized by Wilson and Downer for the Sterling Winthrop Drug Company. The compounds illustrated below have been tested and found to have varying potential as central nervous system depressants.
The Effect Of Dimethyl Sulfoxide And Acetic Acid On The Decomposition Of O-Methoxy, W-Diazo-Acetophenone, Andrew Laurence Colb
The Effect Of Dimethyl Sulfoxide And Acetic Acid On The Decomposition Of O-Methoxy, W-Diazo-Acetophenone, Andrew Laurence Colb
Honors Theses
The acid-induced decomposition of o-methoxy, w-diazo, acetophenone might proceed by wither of two pathways. Huisgen (1) postulated that the mechanism was either “catalytic” (equation 1) or “stoichiometric,” (equation 2) and the differences in the mechanisms were directly related to acid concentration, nucleophilic power of the anion of the acid, and the ionic strength of the medium. Sheffer’s (2) reactions with o-methoxy, w-diazo acetophenone were carried out in ether, a non-polar medium. The aim of this researcher’s study was to determine the reaction course for the decomposition of o-methoxy, w-diazo acetophenone, in a highly polar, slightly nucleophilic medium containing nucleophilic acetate …
A Study Of The Coordination Complex Dichlorobis - [1, 10 Phenanthroline] Cobalt (Iii) Chloride, Richard Carle Goodson
A Study Of The Coordination Complex Dichlorobis - [1, 10 Phenanthroline] Cobalt (Iii) Chloride, Richard Carle Goodson
Honors Theses
One of the traditional areas of study in chemistry has been that of coordination chemistry. The concern of this study is with a particular coordination complex and hence, by way of introduction, something should be said about coordination chemistry. A considerable amount of work has been previously applied to the study of [Co(phen)2(Cl)2] Cl by Ablov and Palade (2) and by Pfeiffer and Werdelmann (3). Using different mehods each group prepared the cis form of the geometric isomers through the literature seems to indicate that neither group resolved the optical isomers of the cis form. Ruid (4) attempted to resolve …
Phenyltrichlorosilane Alkoxylation Reaction Kinetics - A Mathematical Model, Jule Jay Dubois
Phenyltrichlorosilane Alkoxylation Reaction Kinetics - A Mathematical Model, Jule Jay Dubois
Honors Theses
Several models of the chemical kinetics of the phenyltrichlorosilana reaction with ethanol are described and tested. Redistributions and activated complexes were considered for modifying the basic competitive-consecutive reaction kinetics assumed to govern the reaction. The reaction process variable of silane concentration was investigated to test the model.
The Electrogeneration Of Organic Precipitating Agents, Jeannine Martha Keane
The Electrogeneration Of Organic Precipitating Agents, Jeannine Martha Keane
Honors Theses
The purpose of this research was to investigate the electrogeneration of organic precipitating agents with a coulometric measurement of the precipitant as the ultimate aim.
Synthesis Of N-Benzyl-N-Methyl-Β-Chloro-Β(P-Chlorophenyl)-Ethylamine-Hydrochloride, Van Saxton Hubbard
Synthesis Of N-Benzyl-N-Methyl-Β-Chloro-Β(P-Chlorophenyl)-Ethylamine-Hydrochloride, Van Saxton Hubbard
Honors Theses
Classes of compounds often have similar characteristics and activities. However, it has been showin in pharmacological studies that a small change in a structure produced by a substitution of an atom or a group of atoms on the original compound may cause a marked change in biological activity. When a certain compound shows usefulness as a drug, many variations of this compound are studied to see if a more useful form can be made. Two characteristics looked for are (1) effectiveness, which includes the onset or how long before the drug takes effect, and the duration or how long the …
Ion Exchange Resin Impregnated Paper Chromatography Of Some Typical Chlorinated Pesticides, Stephen F. Nagy
Ion Exchange Resin Impregnated Paper Chromatography Of Some Typical Chlorinated Pesticides, Stephen F. Nagy
Honors Theses
The purpose of this project was to examine the effect the ionic immobile phase of various ion exchange resin-impregnated papers has on the separability of some typical chlorinated pesticides; the ultimate goal was devising an ion exchange resin-impregnated paper chromatographic system which would provide better chlorinated pesticide resolution than conventional paper chromatographic methods.
Synthesis Of Fluorinated Acetyl Choline, Joel Beryl Loewenstein
Synthesis Of Fluorinated Acetyl Choline, Joel Beryl Loewenstein
Honors Theses
The purpose of this research was the practical synthesis of a fluorinated acetyl choline.
Rates Of Deuterium Exchange From Deuterated M-Dichlorobenzene In Methanolic Sodium Methoxide Solutions, Rita Rose Boggs
Rates Of Deuterium Exchange From Deuterated M-Dichlorobenzene In Methanolic Sodium Methoxide Solutions, Rita Rose Boggs
Honors Theses
Rate constants were determined for deuterium exchange fro.m m-diohlorobenzene-2-d in 0.5 to 5 molar methanolic sodium methoxide solutions at 80.3° C.
Since this is a base catalyzed reaction, an attempt was made to correlate the rates with the appropriate basicity parameter. The methoxide ion concentration was an entirely inadequate parameter since a plot of log k1 against log [OCH3] showed a linear variation with a slope of 2.40. Significant correlation would demand a slope of unity. The D0 function provided correlation for all kinetic runs except those of sodium methoxide concentrations higher than 4.05 M. The H_ function failed to …
The Effect Of Pyridine And Some 4-Substituted Pyridines On Corrosion Inhibition, Eugene Andrew Grossi
The Effect Of Pyridine And Some 4-Substituted Pyridines On Corrosion Inhibition, Eugene Andrew Grossi
Honors Theses
A study of the corrosion inhibition activity of pyridine and eight of its 4-substituted derivatives was undertaken. The effect of these compounds on the corrosion of carbon steel in deoxygenated aqueous ammonium citrate solution at room temperature was studied.
Lattice Topologies, Alan A. Bishop
Geology Of The Cerro Pelon-Arroyo De La Jara Area, Santa Fe County, New Mexico, Alvis Lee Lisenbee
Geology Of The Cerro Pelon-Arroyo De La Jara Area, Santa Fe County, New Mexico, Alvis Lee Lisenbee
Earth and Planetary Sciences ETDs
The Cerro Pelon-Arroyo de la Jara area is a north-northwesterly plunging syncline at the southern end of the Española basin. Exposed rock units consist of more than 5,000 feet of Mesozoic and Cenozoic shale and sandstone intruded by Oligocene diorite sills and andesite and latite dikes related to the Ortiz intrusive center to the west.
The syncline is affected by several fault systems with both normal and strike-slip movement represented. Northerly trending faults of the east limb combine with a monoclinal flexure to produce an over-all lowering of the section to the west. These faults appear to be related to …
Thermal And Photochemical Decompositions Of The Chloride Salt Of Ortho-Diazoiumphenlyacetic Acid, John Oliver Rosser
Thermal And Photochemical Decompositions Of The Chloride Salt Of Ortho-Diazoiumphenlyacetic Acid, John Oliver Rosser
Honors Theses
Ortho-nitro-phenylacetic was synthesized, diazotized, and subjected to thermal and photochemical decomposition. Indazole is formed when the diazonium chloride salt was thermally decomposed in water. When carbon tetrachloride was used as a solvent, a lactone-like product was formed. When an excess of pyridine in carbon tetrachloride was used no decomposition took place. Photochemical decompositions using a mercury vapor lamp resulted in a combination. of products when methanol was used as solvent and indazole when water was the solvent.
Rapid Calculation Of Electron Scattering Factors, Jerry Peacher, John G. Wills
Rapid Calculation Of Electron Scattering Factors, Jerry Peacher, John G. Wills
Physics Faculty Research & Creative Works
The phase amplitude method is used to reduce the radial Schrödinger equation to two separate differential equations, one for the phase and one for the amplitude. These functions are both smooth as opposed to the rapidly oscillating solution of the radial Schrödinger equation for electron energies in the kilovolt range. The partial-wave phase shifts were obtained rapidly by integrating the differential equations for the phase and amplitude numerically. Hartree-Fock and Thomas-Fermi-Dirac fields were used in the calculation. Results for argon and uranium are given in order to compare with previous results. It was found that the WKBJ approximation to the …
A Study Of Cotorsion Groups, Arlo D. Davis
Stratigraphic Cross Section Of Paleozoic Rocks Of Nebraska, Russell Smith, Raymond Burchett
Stratigraphic Cross Section Of Paleozoic Rocks Of Nebraska, Russell Smith, Raymond Burchett
Conservation and Survey Division
No abstract provided.
Environmental Effects On The Resistivity Of Palladium-Silver Alloy Films In High Vacuum, Frank Snyder
Environmental Effects On The Resistivity Of Palladium-Silver Alloy Films In High Vacuum, Frank Snyder
Masters Theses & Specialist Projects
The reported usage of the palladium-silver alloy films as resistors in the electronics industry has been in encapsulated form. By mounting the resistor inside vacuum electron devices, there is the possibility of eliminating the encapsulation. A literature search has revealed no reported efforts of experiments with unencapsulated resistors and certainly no reports of the palladium-silver alloy resistor in vacuum tubes or other high vacuum environments. Therefore, the research reported in this thesis will concentrate on the environmental effects on resistivity of palladium-silver alloy films in high vacuum.
A Pre- And Post-Improvement Study On Six Southeast Kansas Strip-Mine Lakes, William Thomas Waller
A Pre- And Post-Improvement Study On Six Southeast Kansas Strip-Mine Lakes, William Thomas Waller
Electronic Theses & Dissertations
During the last sixty years extensive experimental research has been conducted in an attempt to establish methods of controlling the acid conditions resulting from coal mine operations.
It was the purpose of this research to determine the feasibility of reclaiming acid strip-mine lakes for use as potential fisheries management areas. To accomplish the objectives outlined above a two-phase program was initiated. The first phase involved the physical alteration of the drainage areas of the experimental lakes included in this study in an attempt to divert all visible signs of acid drainage to areas other than those incorporated into the drainage …
A Cephalometric Study Of The Face And Dentition Of Several Contemporary Western United States And Alaskan Eskimo Groups, Robert C. Parkard
A Cephalometric Study Of The Face And Dentition Of Several Contemporary Western United States And Alaskan Eskimo Groups, Robert C. Parkard
Loma Linda University Electronic Theses, Dissertations & Projects
A total of 223 cephalometric radiographs selected from six contemporary western United States and Alaskans native groups were analyzed by use of the Bjork cephalometric analysis. Those native groups selected were the Eskimos, Apaches, Navajos, Papagos, Pimas and Mayos. Approximately thirty to forty natives from each group were used in the study with ages ranging from thirteen to thirty-five years. The majority were in the fifteen to twenty year age range.
All data was submitted to various statistical analyses to establish a mean, standard deviation, and other relevant values for each of the native groups and to compare these values …
A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh
A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh
Archived Theses and Dissertations
No abstract provided.
An Odontometric Study Of Five Contemporary Western United States Indian And Alaskan Eskimo Groups, John A. Matis
An Odontometric Study Of Five Contemporary Western United States Indian And Alaskan Eskimo Groups, John A. Matis
Loma Linda University Electronic Theses, Dissertations & Projects
The morphologic characteristics of the oral cavity in five contemporary Western Indian and Alaskan Eskimo groups have been investigated by the use of study models of the dental archs. The sample consisted of 216 individuals, including 44 Navajos, 43 Apaches, 40 Papagos, 42 Pimas and 47 Alaskan Eskimos.
The first purpose of the study was to determine the extent of investigator error. This was accomplished by remeasuring many morphologic traits of the dentition in 125 Indians which had previously been measured by different investigators using the same study models. It was found that investigator error can be significant, even in …