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Articles 286921 - 286950 of 293303
Full-Text Articles in Physical Sciences and Mathematics
Evaluation Of Methods Used In The Determination Of Stability Constants Of The Thallium (Iii)-Chloride System At Twenty-Five Degrees, Nelson Kent Dalley
Evaluation Of Methods Used In The Determination Of Stability Constants Of The Thallium (Iii)-Chloride System At Twenty-Five Degrees, Nelson Kent Dalley
Theses and Dissertations
The difficulties encountered in the determination of equilibrium constants in systems with small, not directly rneasureable free ligand concentrations are discussed. These difficulties are illustrated using the determination of the formation constants of the Tl(III)-Cl- system as a specific example. Four methods are used and evaluated in this study. They are (1) the corresponding solutions method, (2) the method of Fronaeus, (3) the solubility of AgCl in Tl(III) solution method and (4) the method of Hugus. A discussion and derivation of each of these methods is given. The first three methods given and free ligand concentration data from which formation …
Green's Relations And Dimension In Abstract Semi-Groups, George F. Hampton
Green's Relations And Dimension In Abstract Semi-Groups, George F. Hampton
Doctoral Dissertations
This thesis originated in an effort to find an efficient algorithm for the construction of finite inverse semigroups of small order. At one stage in trying to devise such a scheme, an attempt was made to construct an inverse semigroup by adjoining two non-idempotent elements to a semi-lattice in such a way that each of them would be D-equivalent to a pair of distinct D-equivalent idempotents. It was noticed taht such adjunction yielded an inverse semigroup only when the elements of the pari were incomparable in the partial ordering of the semilattice, and only when, for each positive integar n, …
The Preparation Of Nursing Care Guides From A Study Of Nursing Problems In African Rural Hospitals, Edith L. Gillham
The Preparation Of Nursing Care Guides From A Study Of Nursing Problems In African Rural Hospitals, Edith L. Gillham
Loma Linda University Electronic Theses, Dissertations & Projects
This study was conducted to make nursing care guides which can be used by African students of nursing in making individualized nursing care plans. The nursing problems which were met in African rural hospitals served as a basis for the nursing care guides. Data for the study were obtained through questionnaires which were airmail to ten rural hospitals in Africa. Eight of the hospitals responded to the questionnaires.
The types of employees, the hospital facilities, and diseases of patients hospitalized during 1963 were studied. Special emphasis was placed upon the nursing problems found in the hospitals. These items were employed …
Metabolism Of Thiamine And The Effect Of Some Antagonists, Russel M. Bender
Metabolism Of Thiamine And The Effect Of Some Antagonists, Russel M. Bender
Theses and Dissertations
To investigate the possibility that thiamine has more than one vital role in the mammalian system, it was decided to use the antagonists pyrithiamine and oxythiamine, and to utilize carbon-14 labeled compounds to more effectively study the vitamin and the above-named antagonists. To make it more effective, we felt that perhaps differences between the localization of oxythiamine and pyrithiamine could be detected in the brain. We also considered and tested the possibility that either or both of the antagonists would alter the localization of thiamine. Essentially, two procedures were used in this study. One was a counting method and the …
A Ti-Hg Collision Cross Section, Edward E. Stepp, Richard A. Anderson
A Ti-Hg Collision Cross Section, Edward E. Stepp, Richard A. Anderson
Physics Faculty Research & Creative Works
The lifetime of the 63P1 state of Hg was observed as a function of Tl density at two different Hg pressures. From these data it appears that at high Tl densities the lifetime of the 63P1 state of Hg is controlled by collisions with Tl atoms. Using this assumption and simple gas kinetic theory, a cross section for these collisions was calculated.
Ground-Water Appraisal Of The Meadow Valley Area, Lincoln And Clark Counties, Nevada, F. Eugene Rush
Ground-Water Appraisal Of The Meadow Valley Area, Lincoln And Clark Counties, Nevada, F. Eugene Rush
Publications (WR)
This report, the 27th in the series of reconnaissance ground-water studies which were initiated following authorization by the I960 Legislature, gives the results of a study of the Meadow Valley area. This area includes eight valleys in southeastern Nevada - - Patterson, Spring, Eagle, Dry, Rose, Panaca, Clover, and Lower Meadow Valley - - all part of the Colorado River drainage system.
This study was made and report prepared by F. Eugene Rush, Geologist for the U. S. Geological Survey.
These reconnaissance ground-water resources surveys make available pertinent information of great and immediate value to many State and Federal agencies. …
Potential Pharmaceutical Derivatives Of Β-Aminoethylpiperazine, Brian A. Dementi
Potential Pharmaceutical Derivatives Of Β-Aminoethylpiperazine, Brian A. Dementi
Master's Theses
This thesis is concerned with the design and preparation of certain organic compounds which are expected to have medicinal properties. A discussion will be given which has essentially a two-fold purpose. The first is to discuss somewhat briefly the currently accepted method of rug design, and the second to show to what extent this method has been followed in the design of the compounds prepared.
A Study Of The Infrared Spectra Of A Group Of Hydroxyalkylamine Hydrochlorides, Lawrence Ingram Briel
A Study Of The Infrared Spectra Of A Group Of Hydroxyalkylamine Hydrochlorides, Lawrence Ingram Briel
Master's Theses
The infrared spectra ot twenty amine bydroohlorides were obtained with the Perkin-Elmer Model 21 recording spectrophotometer. The positions of the absorption bands were compared with literature values for pertinent structural group frequencies. A system of coding the spectral data was devised so that an IBM 1620 digital computer could make the comparisons for a large number of' group frequencies. Good agreement was observed between the positions of the absorption bands in the experimental spectra and those of pertinent group frequencies reported in the literature.
Of the ten symmetrical diamines which were studied, six contained the primary hydroxyl group. Two …
Angular Correlation Of Co60, Henry Kuhlman
Angular Correlation Of Co60, Henry Kuhlman
Masters Theses
Chapter I
Introduction
The probability that a radioactive nucleus will emit a gama ray may depend on the angle between the nuclear spin axis and the direction of emission. The radiation pattern of a sample of randomly oriented nuclei is isotropic. An anisotropic pattern may be observed if the nuclear spin axes are aligned.
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
Masters Theses
Introduction
It has been shown that ketohydrazones react with lead tetraacetate to give azoacetates in good yields (11) according to the following equation:
R2C=N-NH-R + Pb(OAc)4 → R2C(OAc)-N=N-R + Pb(OAe)2 + HOAc
The reaction of the structurally related 4,4- disubstituted ketosemicarbazones with lead tetraacetate quite unexpectedly gave carbamates in good yields (10) presumably according to the following equation:
R2C=N-NH-Co-NR2 + Pb(OAc)4 → R2C-O-CO-NR2 + N2 + Pb(OAc)2 + HOAc
CO
ı
CH3
Basic-Data Report Saline County, Nebraska, Philip A. Emery
Basic-Data Report Saline County, Nebraska, Philip A. Emery
Conservation and Survey Division
No abstract provided.
Variation Of Human Stature In India., N. T. Mathew Dr.
Variation Of Human Stature In India., N. T. Mathew Dr.
Doctoral Theses
This is the first investigation on a large-sc le (1,47,066 measurements) of human stature in India based on deta from all pers of the country. Work done hitherto has been on much smaller serics which can in no way be considered representative of the country as a whole. In the present study certain inte- resting ond inportant results have been obtained which we shall now summarise. lany of the comparisons between meaningful groups involve smell differences which would require falrly large samples to establish with statistical signific- ance. This consideration will apply not only to stature but to other hody …
Spectroscopic Studies Of Tris (2,2'-Bipyridine)- And Tris (I, 10-Phenanthroline) Iron (Ii), -Ruthenium (Ii), And -Osmium (Ii)., Sonia Lee Sabath
Spectroscopic Studies Of Tris (2,2'-Bipyridine)- And Tris (I, 10-Phenanthroline) Iron (Ii), -Ruthenium (Ii), And -Osmium (Ii)., Sonia Lee Sabath
Chemistry and Chemical Biology ETDs
The tris(2,2'-bipyridine)- and tris(l,10-phenanthroline) complexes of iron(II), ruthenium(II), and osmium(II) were synthesized, purified, and characterized by analyses. The solution absorption spectra of the compounds were measured both in the ultraviolet and visible regions. The observed ultraviolet absorption bands of the ruthenium and osmium complexes were assigned entirely to transitions, the prominent bands being assigned to ligand (perturbed) transitions by comparison with the published assignments of the corresponding bands in analogous iron complexes. The visible absorption spectra for iron(II) and ruthenium(II) complexes were attributed entirely to singlet-singlet charge transfer transitions. The strong visible absorption bands of osmium(II) complexes were also assigned …
The Synthesis And Evaluation Of Some 2-Arylindenes And 2-Aryl-3h-Benz[E]Indenes As Liquid Scintillation Solutes, James Leslie Schornick
The Synthesis And Evaluation Of Some 2-Arylindenes And 2-Aryl-3h-Benz[E]Indenes As Liquid Scintillation Solutes, James Leslie Schornick
Chemistry and Chemical Biology ETDs
A scintillator, in the chemical sense, is a system which can convert radioactive particle energy to visible and near ultraviolet photon energy. A phenomenon related to scintillation is fluorescence. The difference between scintillation and fluorescence is the source of excitation energy. In the case of scintillation, the exciting energy comes from radioactive particles, while in fluorescence, the exciting energy comes from ultraviolet light.
A Study Of The Effect Of Varying Serum Phenylalanine Levels On Changes In Intelligence Quotient, Darlene Imai Manullang
A Study Of The Effect Of Varying Serum Phenylalanine Levels On Changes In Intelligence Quotient, Darlene Imai Manullang
Loma Linda University Electronic Theses, Dissertations & Projects
Data from thirty medical records of phenylketonuric children under treatment were investigated to determine at which serum phenylalanine level (0-3.9 mg. %, 4-7.9 mg %, 8-11.9 mg. %, greater than 12 mg. %) there would be the greatest increase in intelligence. The children involved in the study were divided into the following groups according to the age dietary treatment was initiated: 0 through 5 months, 6 through 11 months, 12 through 23 months, and over 2 years of age.
Among 6 patients who were placed on the diet during the first 5 months of life, it appears that the optimal …
Paleoecology Of Pseudozaphentoides Verticillatus (Barbour) In The Plattsmouth Limestone (Pennsylvanian), Robert Francis Diffendal Jr.
Paleoecology Of Pseudozaphentoides Verticillatus (Barbour) In The Plattsmouth Limestone (Pennsylvanian), Robert Francis Diffendal Jr.
Open Access Master's Theses (through 2010)
The purpose of this paper is to (1) delineate precisely the exact areal distribution and stratigraphic position within the Plattsmouth limestone member of any occurrence of Pseudozaphrentoides verticillatus (Barbour) and (2) to study the abiotic and biotic aspects of the Plattsmouth limestone in order to offer some inferences as to the paleoecological significance of these occurrences.
The Plattsmouth limestone in Nebraska is exposed in numerous quarries along the sides of the Weeping Water valley and along the Missouri River bluffs from Plattsmouth, Nebraska south to the Queen Hill quarry. Within the Plattsmouth, corals rapidly diminish in number away from the …
Aspects Of The Reactions Of Aliphatic Methoxydiazoketones, Francesco Gioacchino Belli
Aspects Of The Reactions Of Aliphatic Methoxydiazoketones, Francesco Gioacchino Belli
Honors Theses
It was the purpose of this research to investigate the cyclization of the aliphatic methoxydiazoketohe, 1-diazo-4-methoxy-4-penyl-2-butanone (I), when treated with BF3 in ether.
Separation And Radiochemical Study Of Molybdic And Tungstic Oxides, John Hotchkiss Boles
Separation And Radiochemical Study Of Molybdic And Tungstic Oxides, John Hotchkiss Boles
Honors Theses
In the work presented here, tungsten and molybdenum are precipitated and chemically separated as much as is possible. The products are collected and irradiated with thermal neutrons and the concentration of tungsten determined. In this way only that tungsten forming a complex or dissolving into the molybdenum crystal will be measured.
A Proposed Method Of Separation And Analysis Of The Au(Cn)2 And Au(Cn)4 Complexes, Richard Edward Beane
A Proposed Method Of Separation And Analysis Of The Au(Cn)2 And Au(Cn)4 Complexes, Richard Edward Beane
Honors Theses
Due to its relative scarcity, gold has always held a high value to civilizations compared to other metals which are more common and easier to obtain. Various methods of extraction of the metal have been used throughout history, the most successful of which are washing and dissolution. The most important method of recovery at the present time is dissolution by cyanidation. In order to study the electron exchange between the Au(CN)-2 and Au(CN)-4 complexes, it must be possible to obtain both separately, mix them together in solution, separate them once again, and distinguish between the two complexes to determine the …
Synthesis Of The Bicyclo-(5,5,0)-Dodecane System, Anthony Angelo Gallo
Synthesis Of The Bicyclo-(5,5,0)-Dodecane System, Anthony Angelo Gallo
Honors Theses
The bicycle-(5, 5, 0)-dodecane system consists of two fused seven membered rings. (I) The numbers five, five and zero are arrived at by the fact that counting the number of carbon atoms from one bridgehead carbon to the other yields five, five and zero by the three possible routes. This system can exist in several states of unsaturation. One such state has been given the name heptalene. (II) The object of this project is to propose a new synthesis of the bicycle-(5, 5, 0)-dodecane system.
On The Recovery Of The Nitrates Of Uranyl Ion And Silver (I) Ion From Laboratory Residua, Bruce Bertolette Hardman
On The Recovery Of The Nitrates Of Uranyl Ion And Silver (I) Ion From Laboratory Residua, Bruce Bertolette Hardman
Honors Theses
Uranium became known in the same epoch of history that saw the discovery of the planet Uranus. It was so named. Uranium is a rather active element and never occurs free in nature. Its ores include uraninite is by far the most important. This ore is sometimes called pitchblende and has a simplest empirical formula of UO2. Due to the fact that it is always found partially oxidized its composition may range between that of UO2 and U3O8. This latter form contains both tetra and hexavalent uranium. An illustrative structure is given below. It is sometimes regarded as uranyl uranate, …
An Examination Of Basicity Functions, Lewis Morton Gedansky
An Examination Of Basicity Functions, Lewis Morton Gedansky
Honors Theses
Acids and bases have long been subjects of interest to the chemist. These two classes of chemical compounds play an important role in the chemical world in regards to their reaction with each other and their use as catalytic agents. They are known to react with each other in either of two ways. The reaction which is most familiar is the standard neutralization reaction which results in the formation of a salt and water. It can be illustrated by the reaction of an acidic substrate, HA, reacting with the base, sodium hydroxide. Such a reaction conforms with the Bronsted-Lowry definition …
The Determination Of The Ratios U234/U238 And Th228/Th232 As Leached From Storm King Granite, James Robert Lawrence
The Determination Of The Ratios U234/U238 And Th228/Th232 As Leached From Storm King Granite, James Robert Lawrence
Honors Theses
In nature there are three major decay series that involve naturally occurring uranium and thorium as parent nuclides. Two of the three series; U-238, TH-232 and U-235; are shown in figure I. Of the three series two, U-238 and the Th-232 series, are examined in the study. This is because the amount of U-235 in nature is very small relative to the amount of U-238 and Th-232. This study is concerned with the presence of U-238 and Th-232 and their uranium, thorium and radium daughter products in the silicic intrusive rock, Storm King Granite. Uranium and thorium have large iconic …
Heats Of Solution Of Saturated Mixed Electrolytes, Stephen Alan Rudolph
Heats Of Solution Of Saturated Mixed Electrolytes, Stephen Alan Rudolph
Honors Theses
Reliable data on heats of solution of concentrated mixed electrolytes is a rather scarce. This work purports to give formulas for the heat of solution at saturation of an electrolyte in a solution saturated with respect to still another electrolyte. These formulas are in terms of solubility data and non-calorimetric thermodynamic data and are as follows.
Phosphoric Acid - Catalyzed Hydrolysis Of Benzeneboronic Acid, Kenneth Sumner
Phosphoric Acid - Catalyzed Hydrolysis Of Benzeneboronic Acid, Kenneth Sumner
Honors Theses
At a phosphoric acid concentration of over 80%, the kinetics are not first - order, but instead, the reaction appears to be autocatalytic. Is it the purpose of this research to determine if this phenomenon is real, and if so, to elucidate the cause of the autocatalysis.
Attempted Preparation Of 1-Diazo-6-Methoxy-2-Hexanone, Edmund Joseph Zalewski
Attempted Preparation Of 1-Diazo-6-Methoxy-2-Hexanone, Edmund Joseph Zalewski
Honors Theses
To show the appreciable yield of cyclic compounds upon treating the methoxydiazokotones with boron trifluoride etherate.
The Catalytic Decomposition Of Sucrose, Richard Wells Bishop
The Catalytic Decomposition Of Sucrose, Richard Wells Bishop
Honors Theses
The object of this research was to gain enough information from the products of sugar decompositions to allow the proposal of a mechanism for these decompositions. The information on sucrose would be combined with that for glucose and fructose to make this proposal.
A Hydrogen Electrode Via Ferrous Ion And Ultraviolet Light, Richard Leslie Harlow
A Hydrogen Electrode Via Ferrous Ion And Ultraviolet Light, Richard Leslie Harlow
Honors Theses
The purpose of this research is to investigate the photoelectric properties of an acidified ferrous-sulfate solution. It is known that in the presence of ultraviolet light, the equilibrium is shifted to the right. The idea is proposed that the hydrogen gas produced by this reaction might be absorbed on a platinum grid, thereby creating a hydrogen electrode. A cell is thus proposed in which two platinum electrodes are immersed in the same solution of ferrous sulfate and sulfuric acid. The area surrounding one electrode is to be illuminated with ultraviolet light. Some of the hydrogen gas produced in that area …
An Investigation Of The Ternary System: Magnesium Sulfate - Urea - Water, David Brian Holland
An Investigation Of The Ternary System: Magnesium Sulfate - Urea - Water, David Brian Holland
Honors Theses
Magnesium sulfate hydrate and urea are common constituents of many commercial fertilizers. It is the purpose of this investigation into the ternary system: magnesium sulfate – urea – water to try to resolve these discrepancies and also to further investigate the ternary system.
Synthesis Of 1-Diazo-3-Methoxy-3-Phenyl-2-Propanone And Reaction With Boron Trifluoride Etherate, Harvey Harris Kagan
Synthesis Of 1-Diazo-3-Methoxy-3-Phenyl-2-Propanone And Reaction With Boron Trifluoride Etherate, Harvey Harris Kagan
Honors Theses
It has been found that the normal reaction of diazoketones with an acid to form substituted methyl ketones is often subverted by cyclization to form closed chain cyclic ketones. Some work has been done with aromatic diazoketones but very little has been done with the aliphatic diazoketones. The object of this research was to bring about ring closure of a four membered ring from an aliphatic diazoketone. It was decided to put a phenyl group on the aliphatic chain in order to obtain crystalline derivatives. Specifically, the object of this work was to bring about the cyclization of 1-diazo-3-methoxy-3-phenyl-2-propane. The …