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Articles 67591 - 67620 of 69103
Full-Text Articles in Physical Sciences and Mathematics
A Study Of The Catalytic Hydrogenation Of Methoxybenzenes Over Platinum And Rhodium Catalysts, Robert Gene Thompson
A Study Of The Catalytic Hydrogenation Of Methoxybenzenes Over Platinum And Rhodium Catalysts, Robert Gene Thompson
Doctoral Dissertations
[From the Summary]
The catalytic hydrogenation of methoxybenzenes and other aromatic methoxyl compounds has been studied. Hydrogenation of the aromatic ring was usually accompanied by some cleavage of the methoxyl groups. This cleavage occurred predominately upon the carbon-oxygen bond adjacent to the aromatic ring. The cleavage reaction was found to occur only as a part of the aromatic hydrogenation process. The amount of cleavage was found to be dependent upon the catalyst used. Platinum led to extensive methoxyl cleavage while rhodium catalyzed ring saturation with little cleavage. Also found to influence the extent of cleavage were reaction temperature …
Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson
Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson
Theses and Dissertations
This work represents a study on the biological oxidation of molybdenite, MoS2. The principal objective of this study was to investigate the possibility of the biological oxidation of molybdenite, to determine the physical and chemical conditions under which the oxidative process occurs, and to develop a strain of bacteria or alter the activity of the microorganisms by acclimatization to increase their activity on sulfide minerals, in particular molybdenite. Minerals used in this study were pyrite (FeS2), chalcopyrite (CuFeS2), molybdenite concentrate, and molybdenite ore. The microorganisms used in this investigation were autotrophic bacteria obtained from the leaching streams of Bingham Canyon, …
The Instability Constant Of The Cobaltous Citrate Complex Ion Using Cobalt-⁶⁰ As A Tracer, Lee T. Cox
The Instability Constant Of The Cobaltous Citrate Complex Ion Using Cobalt-⁶⁰ As A Tracer, Lee T. Cox
Theses and Dissertations
The instability constant of a substance shows the tendency of a substance to dissociate into simple ions. The stability of the substance can be related to stabilities of other substances through the instability constant. Schubert gives a method for the determination of the instability constant which involves measurements of the adsorption of a radiotracer cation on a cation exchange resin. Two different types of resin were employed in this research. It was found that with a resin containing carboxylic acid exchange groups the adsorption of the cobaltous ion changed rapidly with pH but with a resin containing nuclear sulfonic acid …
A Historical Survey Of Methods Of Solving Cubic Equations, Minna Burgess Connor
A Historical Survey Of Methods Of Solving Cubic Equations, Minna Burgess Connor
Master's Theses
It has been said that the labor-saving devices ot this modern age have been made possible by the untiring efforts of lazy men. While working with cubic equations, solving them according to the standard methods appearing in modern text-books on the theory of equations, it became apparent, that in many cases, the finding of solutions was a long and tedious process involving numerical calculations into which numerous errors could creep. Confessing to laziness, and having been told at an impressionable age that "any fool can do it the hard way but it takes a genius to find the easy …
The Dipole Moments Of A Series Of N, N-Diphenylbenzamides, James William Cooke
The Dipole Moments Of A Series Of N, N-Diphenylbenzamides, James William Cooke
Master's Theses
In recent years amides have been used in synthetic fibers, plastics and in medicinal chemistry. Under standably, the literature contains many preparations and reactions of unsubstituted, monosubstituted and disubstituted amides, however, their structure has received very little attention. The information avail able on the amide group structure originates from studies made on the unsubstituted and mono substituted compounds. The phenomenon of association of the amides has received considerable attention.
Amperometric Titrations Using A Rotating Platinum-Wire Electrode, James E. Buckley
Amperometric Titrations Using A Rotating Platinum-Wire Electrode, James E. Buckley
Bachelors’ Theses
This thesis is an outgrowth of a desire to do precise analytical work with the use of an instrument that would be simple to operate and yet give reproducible results. It is based largely on a method of precipitation titration in those solutions where an internal indicator could not be used feasible because the concentration of the desirable ion was either to low, or the solution too turbid.
My choice of using the platinum microelectrode in these titrations was based on the fact that this electrode could be easily assembled, and take little effort to maintain. It also is advantageous …
A Correlation Of The Catalytic Activity Of Various Mixtures Of Rhenium And Molybdenum Sulfides In Liquid-Phase Hydrogenation Of Certain Reducible Organic Groups, Li-Chen Hsu
Theses and Dissertations
The promoter action of mixtures of catalysts has been reported in literature to be valuable in industries. Whether mixtures of rhenium and molybdenum sulfides would have promoter actions in the hydrogenations of certain reducible organic groups was the main object of this research. Mixtures of rhenium and molybdenum sulfides of various compositions were prepared by three different methods, i.e., (a) by saturating perrhenate and molybdate with hydrogen sulfide in hydrochloric acid solutions, (b) in ammonium hydroxide solutions followed by acidification, and (c) by treating perrhenate and molybdate with thiosulfate in dilute sulfuric acids followed by extraction with toluene to remove …
Tetrazolium Salts, Andrew Garnett Richardson
Tetrazolium Salts, Andrew Garnett Richardson
Master's Theses
Tetrazolium salts, as the name indicates, are quartenary. Substitution is possible on positions 2, 3, and 5 of the ring as is shown in type formula (I). When these substituent groups are bifunctional ditetrazolium salts of types (II), (III), and (IV) result. Compounds bridged at both R' and R'' at the same time are theoretical possible, but no such cases have been reported, probably on account of the practical limitations of synthesis. The anion, which is indicated by X, may be halide, sulfate, acetate, picrate, succinate, thiocyanate, or practically any atom or group capable of existing as a negative ion.
A New Apparatus For Paper Electrophoresis, Robert John Hodges
A New Apparatus For Paper Electrophoresis, Robert John Hodges
Honors Theses
In paper electrophoresis, taking the idealized case, a charged particle, i.e. a particle which has an excess or deficiency of electrons, resulting in a net electrostatic charge is placed on a strip of moistened filter paper. The moistening is usually done by a buffer solution which serves two purposes: 1. It provides a liquid phase within the structure of the paper through which the particle can travel. 2. It keeps a constant pH throughout the run. After experimenting with several types of apparatus the author decided that a new type of apparatus was needed and could be designed which would …
The Study Of Kojic Acid As A Chelating Agent For Cadium Analysis, Norman Elliot Conger
The Study Of Kojic Acid As A Chelating Agent For Cadium Analysis, Norman Elliot Conger
Honors Theses
The absorption spectra of kojic acid and of cadmium kojate in various solvents have been obtained. From this data, the suitability of kojic acid as a possible analytical reagent for the determination of very small amounts of cadmium in water using ultraviolet absorption methods is discussed. Kojic acid is found to be not suitable for analysis of cadmium using ultraviolet absorption methods.
Various Regular And Irregular Precipitate Structures In Gelatin Gels, Martin Stanley Ferguson
Various Regular And Irregular Precipitate Structures In Gelatin Gels, Martin Stanley Ferguson
Honors Theses
In the field of Colloid Chemistry, precipitate structures in gels have been studied for quite sometime. The formation of a rhythmic band configuration known as Liesegang rings, when an insoluble salt is formed by the gradual diffusion of one ion into a gel containing the other ion has become a common phenomenon. At the outset of this research project, the primary intent was to continue the work of R. DeSieno into a somewhat different regular structure obtained by ionic diffusion in the presence of mercury vapor. This phenomenon to be studied involves the formation and nature of radial lines produced …
Addition Of Tricholorsilane To Isocyanate Radical, Robert Hugh Maliner
Addition Of Tricholorsilane To Isocyanate Radical, Robert Hugh Maliner
Honors Theses
The purpose of this investigation is to synthesize an organo-silicon compound.
A Study Of Applications Of The Heat Of Reaction To Analytical Determinations, David Lawrence Thurber
A Study Of Applications Of The Heat Of Reaction To Analytical Determinations, David Lawrence Thurber
Honors Theses
The purpose of the paper is to summarize the major problems of designing apparatus, and to discuss solutions for some of these, and suggest solutions for others. An attempt has been made to extend the versatility of the method in regard to the technique of titration, the idea being that coulemetric delivery as well as volumetric delivery of reagents might be used.
An Attempt To Improve Certain Physical And Chemical Properties Of Concrete Through The Use Of Various Organic Polymers, Robert Lehrer
An Attempt To Improve Certain Physical And Chemical Properties Of Concrete Through The Use Of Various Organic Polymers, Robert Lehrer
Honors Theses
Through the incorporation of various organic polymeric substances into several kinds of concrete mixes, we have attempted to produce a mixture which offered more than the usual resistance to corrosion by water and acid.
Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen
Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen
Theses and Dissertations
A study of the photo-oxidation of the 2,6-dichlorophenol indophenol-ascorbic couple was undertaken with a view to investigating the postulated mechanism of oxidation by a component of the oxygen evolving sequence operative in photosynthesis. A spectrophotometric method for the measurement of the progress of photo-oxidation was developed. Temperature and pH dependence were determined and the effect of various common inhibitors and physiological substances tested. None of the common Hill reaction inhibitors were effective in the ascorbic acid photo-oxidation in the system used. KCN and catalase as well as a few other high molecular weight proteins were able to inhibit dark auto-oxidation …
The Vertical Gradients Of Ozone Concentration And Its Relation To The Eddy Coefficient Of Diffusion, Joseph Levine
The Vertical Gradients Of Ozone Concentration And Its Relation To The Eddy Coefficient Of Diffusion, Joseph Levine
Physics & Astronomy ETDs
The purpose of this thesis is to apply this method to a tentative evaluation of the eddy coefficient of diffusion. Actually the investigation was more specifically an attempt to relate the difference in ozone concentration between the two stations to the average wind shear and to the vertical thermal stability.
Geology Of The Rinconada Canyon Area, Valencia County, New Mexico., John Mohar Jr.
Geology Of The Rinconada Canyon Area, Valencia County, New Mexico., John Mohar Jr.
Earth and Planetary Sciences ETDs
Within this area are found two small domes superimposed upon the McCarty syncline. North dome, the larger of the two, is located at the head of Rinconada Canyon. South dome is located in the southern part of the area near the mouth of the canyon. Thus far the mineral resources of the area have been of little economic value. There are, however, large deposits of commercial uranium deposit at depth which cannot be disregarded.
A Study Of Isotopic Exchange Between Potassium Iodide And Benzyl Iodide. Solvent Effects, Joseph A. Leary
A Study Of Isotopic Exchange Between Potassium Iodide And Benzyl Iodide. Solvent Effects, Joseph A. Leary
Chemistry and Chemical Biology ETDs
The kinetics of the isotopic exchange reaction between potassium iodide and benzyl iodide in alcoholic solution has been studied thoroughly by Stillson. It was reported that the reaction was much faster in ethanol-acetone mixtures than in absolute ethanol. However, it was not possible to determine whether this was due to acceleration of the reaction by acetone, or to inhibition by ethanol.
The purpose of this investigation was to elucidate further the effect of various solvents on the same exchange reaction. The isotopic exchange reaction between potassium iodide and p-nitrobenzyl iodide was also studied, because it had been investigated in alcoholic …
Geology And Ground-Water Resources Of The Portales Valley Area, Roosevelt And Curry Counties, New Mexico, Sherman E. Galloway
Geology And Ground-Water Resources Of The Portales Valley Area, Roosevelt And Curry Counties, New Mexico, Sherman E. Galloway
Earth and Planetary Sciences ETDs
Since 1910, and particularly since the closing years of World War II, considerable development of the ground water occurring in the valley fill has been made for irrigation purposes. This increase in development has resulted in a progressive decline of the water levels in this area. The results of this study indicate that the water occurring in the valley fill is the only water of good chemical quality occurring in the Portales Valley that can be obtained in quantities that are sufficient for normal irrigation, municipal, industrial, stock, and domestic uses, and that if the present rate of ground water …
Beta And Gamma Distributions, Calvin Rogers
Beta And Gamma Distributions, Calvin Rogers
Mathematics & Statistics ETDs
The purpose of this paper is to exhibit the main properties of Gamma and Beta distributions and show their relation to certain well known distributions.
In chapter II the Gamma and Beta distributions are defined in terms of Gamma and Beta functions. The moments of these distributions are calculated, and the moment generating function and cumulant generating function for the Gamma distribution are obtained. The curves are classified with respect to parameter values and the curves are graphically illustrated in Figures 1, 2, and 3. The exponential distribution, as a special case of interest, is shown to be a Gamma …
Geology Of The Central Front Of The Fra Cristobal Mountains, Sierra County, New Mexico, Richard C. Jacobs
Geology Of The Central Front Of The Fra Cristobal Mountains, Sierra County, New Mexico, Richard C. Jacobs
Earth and Planetary Sciences ETDs
This report includes about seven square miles of the central front of the Fra Cristobal Mountains. The area contains rocks from Precambrian, Cambrian, Pennsylvanian, and Quaternary Age. Fragmentary exposures of the Permian sedimentary rocks are also present.
Geology Of The White Rock Mountain Area, Gunnison County, Colorado, David L. Gaskill
Geology Of The White Rock Mountain Area, Gunnison County, Colorado, David L. Gaskill
Earth and Planetary Sciences ETDs
The White Rock Mountain area in central-western Colorado is included in the northwest corner of the Crested Butte quadrangle and the extreme southwest corner of the Aspen quadrangle. Mineral deposits were recognized in the early seventies, and in the literature the area is referred to as the Elk Mountain District.
The Use Of Kamke's Transformation In Approximating The Zeros Of Orthogonal Polynomials, Robert L. Daniels
The Use Of Kamke's Transformation In Approximating The Zeros Of Orthogonal Polynomials, Robert L. Daniels
Mathematics & Statistics ETDs
The importance of the classical orthogonal polynomials has long been acknowledged. It has not been possible, however, to represent them in such a way that all of their important properties are immediately evident. In particular, the location of the zeros of these polynomials is of considerable interest.
This thesis is primarily concerned with a different technique in which Kamke's transformation is applied to the differential equations frequently used to define these polynomials. The resulting trigonometric differential equations cannot be explicitly solved either, but certain characteristics of these solutions facilitate the derivation of approximations to the zeroes of the solutions.
Geology Of The Canjilon Cauldron Sink Near Bernalillo, Sandoval County, New Mexico, Felix E. Mutschler
Geology Of The Canjilon Cauldron Sink Near Bernalillo, Sandoval County, New Mexico, Felix E. Mutschler
Earth and Planetary Sciences ETDs
Canjilon Hill is located on the west side of the Rio Grande, about 2 3/4 miles north-northwest of Bernalillo. Exposed on the hill is a local unit of breccia, conglomerate, and sandstone, which forms an elongate saucer-shaped body 4100 feet long, 2200 feet wide and 280 to 500+ feet thick. Unlike the underlying Santa Fe formation these strata contain an abundance of large angular basalt pebbles, cobbles, and boulders. In this paper these strata are termed the Canjilon formation of the Santa Fe group. Structural and sedimentological evidence suggest that the Canjilon formation was deposited in a subsidence depression initiated …
The Motion Of A Charged Particle In Homogenous Time-Varying Magnetic Field, Thomas R. Bates
The Motion Of A Charged Particle In Homogenous Time-Varying Magnetic Field, Thomas R. Bates
Physics & Astronomy ETDs
This paper will discuss the motion of a non-relativistic, non-radiating charged particle in an infinite homogeneous magnetic field which varies linearly with time. We shall assume the motion to be confined to a plane perpendicular to the magnetic field.
An Indicator Of Position With Respect To The Earth's Magnetic Field, Lloyd C. Nielsen
An Indicator Of Position With Respect To The Earth's Magnetic Field, Lloyd C. Nielsen
Physics & Astronomy ETDs
A large amount of experimental research in the field of atmospheric physics involves carrying apparatus aloft by means of balloons. Data from balloon-borne instruments may be obtained either by recovery of the apparatus or by radio telemetering during the flight. Of these two methods, the latter is of course the more convenient and reliable, since recovery of the apparatus is time-consuming and often impossible.
Paleozoic Stratigraphy Of The Mud Springs Mountains, Sierra County, New Mexico, John Davis Hill
Paleozoic Stratigraphy Of The Mud Springs Mountains, Sierra County, New Mexico, John Davis Hill
Earth and Planetary Sciences ETDs
This thesis gives a history of the terminology of each of the formations found in the Mud Springs Mountains as well as a discussion of the characteristics of each. The Mud Springs Mountains Section of Paleozoic rocks is 3660 feet thick. Parts of all the Paleozoic systems are represented except the Silurian and Mississippian. The Bliss sandstone is 145 feet thick, the lower 65 feet being late Cambrian and the upper 80 feet being early Ordovician. The El Paso limestone of early Ordovician age is 460 feet thick.
Calorimetric Heats Of Mixing Of Some Nonelectrolytic Binary And Ternary Solutions, James Bevan Ott
Calorimetric Heats Of Mixing Of Some Nonelectrolytic Binary And Ternary Solutions, James Bevan Ott
Theses and Dissertations
The heat of mixing of nonelectrolytic liquids is important in predicting the type of molecular interactions which exist in solutions of nonelectrolyted. The problem was to construct a calorimeter in which these heats of mixing could be measured accurately. Once constructed, the calorimeter was used to measure the heats of mixing of some binary and a ternary solutions. The systems chosen for study were the three liquid pairs formed between benzane, carbon tetrachloride, and cyclohexane, and the ternary mixture of the three. The results of the experimentation are summarized by the following equations. (1) H_12^M = X_1x_2 [103.2 + 13.1(x_1 …
The Instability Of Folded Structures, Robert Del Mar
The Instability Of Folded Structures, Robert Del Mar
Earth and Planetary Sciences ETDs
Folded structures are not necessarily stable through geologic time. "Unfolding" is defined as the changes in attitude through with folded structures go subsequent to their creation by tectonic means, other than by faulting alone. The principal types of unfolding, together with their causes, are: (1) the effect of gravity on isolated structures, and the effects of loading and unloading insofar as the gravitational force is concerned; (2) basining action and its effect on unloading; (3) the action of vertical forces on folded structures; (4) migrating or "wave" folds in relation to unfolding.
Diagnostic Abdominal Aspiration In Acute Abdominal Conditions, George Quan Lee
Diagnostic Abdominal Aspiration In Acute Abdominal Conditions, George Quan Lee
Loma Linda University Electronic Theses, Dissertations & Projects
[Abstract Not Included]