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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An Analysis of the Lincoln-Osbretsky Motor Development Scale with an Emphasis on the Reduction of Total Test Items

Pearman, Roger 01 August 1968 (has links)
The Lincoln-Oseretsky Motor Development Scale is designed to test the motor ability of children between the ages of six and fourteen. It is an individually administered scale consisting of thirty-six motor skill items such as finger dexterity, eye-hand coordination and gross activity of the hands, arms, legs and trunk. Both unilateral and bilateral motor tasks are involved in the scale. Because of this fact, fifty-three test items involve right and left limb performances. The time for administering all the items is usually less than one hour. The purpose of this study was to determine whether or not the number of test items could be significantly reduced so that a reliable assessment or the motor ability of an individual can be made in a much shorter period of time.
2

Spectroscopic Study of Ni(II)-4, 4’, 4’’, 4’ ’’ – Tetrasulfophthalocyanine In Aqueous Solution

Jabra, Issa Ishaq 01 December 1978 (has links)
It was determined spectrally that a monomer-dimer equilibrium exists in aqueous solutions of Ni-TSPC4- over a concentration range of 5 x 10-8 – 10-4 M. Equilibrium measurements were made under natural ionic strength conditions at 29°, 39° and 49°C. The values obtained for the equilibrium constants at 29°, 39° and 49°C were 2.4 x 108, 6.6 x 107 and 2.9 x 107 M-1, respectively. These results indicated that the equilibrium strongly favors dimer formation. This study also showed that nickel is second to copper in enhancing the dimerization of metallotetrasulfophthalocyanine complexes. However, metals in general inhibit dimer formation relative to the free ligand. The dimerization reaction of Ni-TSPC4- is exothermic with thermodynamic parameters of ΔG° = -11.6 kcal/mole, ΔH = -20.9 kcal/mole, and ΔS = -31 e.u. The dimerization process is thus favored from an energetic point of view despite the unfacorable entropy change. Spectral measurements made on Ni-TSPC4- in aqueous pyridine solutions in the concentration range of .05 - 6.0% pyridine (by volume) indicated a dipyridinated dimer complex of Ni-TSPC4- was formed. Using a modified version of the Benesi-Hildebrand equation, the following equilibrium was proposed : D + 2Py = D(Py)2. The overall equilibrium constants for this system at 15°, 21°, 30° and 40°C were 1.7, 1.9, 2.8, 3.6 and 4.4 M-2, respectively. The equilibrium reaction is endothermic with thermodynamic parameters of: ΔG=6.2 kcal/mole, ΔH =6.9 kcal/mole, and ΔS=25 e.u. Thus, the equilibrium reaction was favored thermodynamically due to the favorable entropy change associated with the process. Ligand studies indicated that only pyridine and polupyridine ligands bind to Ni-TSPC4- and cause a spectral change. This study also showed that Ni-TSPC4- cannot be used as an oxygen carrier in biological systems.
3

The Esterases of the Galleria Mellonella Larvae

Juraimi, Salmah 01 August 1986 (has links)
Some properties of esterases of the greater wax moth larvae, Galleria mellonella (L.) were examined and the enzyme partially purified. Tris buffer was chosen as the buffer system over veronal buffer. The former causes less hydrolysis of the acetylsalicylic acid. Esterase activities were determined with acetylasalicylic acid in tris buffer (00.05 M, pH 7.85 with 0.1 M EDTA) and with acetyl-p-hydroxybenzoic acid in the same buffer. The enzyme was partially purified by combination of acetone powder preparation, ammonium sulfate precipitation, ion-exchange chromatography, and gel filtration. The starting enzyme preparation was obtained from aceton powder preparation. The ratio of esterase activity to protein content was increased 1.36-fold by 70% ammonium sulfate precipitation. The ammonium sulfate in the 60-70% saturation range is reproducible with the highest specific activity at 60% saturation. The ammonium sulfate fractionation increased the stability of the enzyme preparation. After 24 hours more than 55% of enzyme activity from the ammonium sulfate precipitate still remained, whereas only about 40% of the enzyme activity from the acetone powder preparation remained. The pH optimum was found to be 8.5 with acetyl-p-hydroxybenzoic acid as the substrate. The esterase had a linear increase in activity with increasing temperature. At 51°C, the specific activity was 27.60 micromoles/min mg protein in comparison to 12.94 micromoles/min mg protein at 20°C. The kinetic behavior of the enzyme with the different substrates was studied. The Vmax and Km values were 12.5 micromoles/min mg protein and 0.435 millimoles, respectively. The energy of activation with acetyl-p-hydroxybenzoic acid was 4.542 kcal K-1 mol-1. The esterase activity was inhibited by mercuric chloride and veratrine sulfate. It was activated by the chelating agent, EDTA. The esterase activity was not affected by p-chloromercuribenzoic acid and eserine salicylate.
4

Photochemistry of beta-Methyl-beta-Nitrostyrene and Its Derivatives

Kassaee, Mohammad Z. 01 June 1976 (has links)
o-CH3, o-CH3O, m-CH3O and p-CF3-β-methyl- β-nitrostyrene (compounds not previously reported) were synthesized using the method of Lappin13 and Robertson.14 These styrenes were irradiated in the U.V. region. The yield of corresponding oximes varied from 85 to 100% in aqueous ethanol. This variation in yield of the oximes was attributed to the effect of the substituent on the phenyl rings of the corresponding styrenes. Electron donating substituents promoted the nitro-nitrite rearrangement and electron-withdrawing groups inhibited this rearrangement. A mechanism is proposed for this reaction which unifies and includes ideas proposed by Chapman2, Pinhey5 and Matsurra.3 The effect of solvent on the irradiation was also studied. The results obtained indicated that the solvent employed does have an effect on the photorearrangement of beta-nitrostyrenes.
5

Oxidation Activity of Catalyst 3-7A Toward Formaldehyde, Hydrogen Cyanide, And Some Alkane Gases

Kawas, John 01 December 1982 (has links)
The activity of Catalyst 3-7A toward the oxidation of formaldehyde, hydrogen cyanide, methane, propane, and isobutene was examined at temperatures between 25°C and 400°C. The catalyst consists of palladium(II) and copper (II) salts impregnated on an alumina support. The oxidation measurements were made primarily with gas chromatographs, although form aldehyde and hydrogen cyanide were also examined using the colorimetric fushsin method and Liebig titrations, respectively. Catalyst 3-7A demonstrated appreciable activity toward the oxidation of all gases studied except formaldehyde where there was no evidence of oxidation. The latter result is quite unexpected since aldehydes are more easily oxidized than alkanes. It is suggested that the inactivity of Catalyst 3-7A toward formaldehyde is attributed to the lack of moisture which is required by the catalyst during oxidation. All oxidation reactions are believed to occur via a Qacker-type process under pseudo-first order conditions with the palladium(II) concentration maintained constant via the presence of copper (II) which oxidizes metallic palladium, the product in the oxidation reaction. The oxidation products in all the gases examined are believed to be carbon dioxide and water except for hydrogen cyanide where an additional product containing nitrogen should be formed but could not be detected with the gas chromatograph. Rate constants (reported in parenthesis) at 400°C for the following gases are hydrogen cyanide (>26.2 sec-1), methane (6.5-6.6 sec-1), propane (>12.8 sec-1), and isobutene (>15.7 sec-1). These results show that hydrogen cyanide is the most active gas to be oxidized by the catalyst excluding carbon monoxide which is the test gas used I our system and has been previously determined to demonstrate the greatest activity with the catalyst. The three alkane gases show an order of oxidation reactivity which lends some support for ruling out an anionic mechanism since tertiary C-H bonds were found to be more reactive than secondary C-H bonds which in turn were shown to be more reactive than primary C-H bonds. A comparison of Catalyst 3-7A with other catalysts reported in the literature which show similar oxidation behavior with gases could not be made due to lack of data regarding their experimental conditions.
6

An Analytical Study of the School Budgets of Kentucky for 1946-47

Cook, Leon 01 August 1950 (has links)
The school budgets of the different school districts of the state of Kentucky are prepared according to law and by the standard plan adopted by the State Board of Education. Kentucky School Law 160.170 demands that each board of education prepare a budget and present it to the State Board of Education for approval. The standard form adopted by the State Board of Education contains the following items or main divisions: General Control, Instruction, Operation of School Plant, Maintenance, Fixed Charges, Auxiliary Service, Transfer of Tuition, Capital Outlay and Debt Services. This study will take the budget of each board of education and divide the amount spent in each division listed above by the census figure of the district and thus find the per capita for each division as well as the total per capita spent on each child in the census. Further, the amount budgeted in each division will be divided by the total amount budgeted to find the per cent spent for each division. The Kentucky Laws and the plan adopted by the State Board of Education do not recommend any certain amount to be spent per capita in each division no do they recommend any certain per cent for each division. This study shows that there is a wide variance among the different districts as to the per capita and the per cent spent for the different items of the budget. It is hoped that this study will make it possible for each superintendent and board of education to see at a glance how their school district compares with any other district in the state. It is not the purpose of the study to find out why so many variances occur, but to show a true picture and to make some recommendations that may be of benefit.
7

The Palladium (II) –Catalyzed Homogeneous Oxidation of 1-Hexene

Kirova, Margarita 01 May 1992 (has links)
The Palladium(II)-catalyzed homogeneous oxidation of 1-hexene in methanolic medium has been studied, copper(II) chloride being used as cocatalyst. Aspects of the kinetics, mechanism and product composition were investigated in several series of oxidations involving variation of hexene concentration, oxygen partial pressure, Cu(II): Pd(II) ratio and concentration and temperature. The progress of the reaction was studied in the course of periodic sampling runs. Reaction products were identified by gas chromatography, and verified by means of GC/mass spectrometry. The expected product of 1-hexene oxidation was 2-hexeanone: however, 3-hexanone occurs as a major coproduct, arising from concurrent Pd(II)-catalyzed isomerization of 1-hexene to 2-hexene. Isomerization is inhibited by excess copper(II) chloride. The overall oxidation is generally consistent with P.M. Henry’s mechanism for Pd(II)-catalyzed alkene oxidation, the rate-limiting step being the π-to σ-rearrangement of the Pd(hexane) complex. The corresponding ketals (2,2-dimethoxyhexane and 3,3-dimethoxyhexane) were also found. Free hexanal was not detected in any oxidation product mixtures; when produced it was found as the dimethyl acetal. Chlorination products were not observed. A surprisingly sharp rate maximum was observed when copper(II) chloride concentration was varied. Two kinetic regions were found to occur in virtually all oxidations. An explanation is proposed for this behavior.
8

Characterization of Combustion Profiles of Co-Fired Coal/Biomass/Limestone Samples by TG and TG/FTIR

Hutchinson, Erik Jon 01 July 1993 (has links)
Recent concerns over declining landfill space and a renewed interest in waste-to-energy technologies have increased the possibilities of co-firing different types of fuels in fluidized bed combustion systems. Fluidized bed combustion systems are idea for co-firing because of their ease in heat conversion and ability to burn a wide range of fuels. Additionally, thermal analytical techniques can be used to screen fuel blends for the fluidized bed combustion systems at a lower cost than directly firing the fuel blends in pilot systems. Three coals, three different municipal solid wastes (MSW), one limestone were combined into nine series of binary fuel mixtures to determine the possible Observed/Theoretical ratios caused by the MSW and /or the limestone to the coal’s combustion profile. After doing so, optimum percentage combinations were determined that should combust efficiently in fluidized bed systems. Consequently, after the combinations were optimized, evolved gas analysis showed a possible 50% reduction in SO2 emission through absorption by limestone.
9

Use of FT-IR and NMR Spectra of the THF Extracts of Mid-Rank Bituminous Coals to Predict Plasticity

Irefin, Samuel Adesoji 01 August 1984 (has links)
Plasticity, which typically develops at 380-420°C, is a unique property of mid-ranked coals. The phenomenon of plasticity in coals has been known for a long time but is still poorly understood. Even among coals of identical subrank and chemical composition, large differences in plastic behavior are commonly encountered. Plastic coals go through a softening and swelling state upon heating before they resolidify. Concurrent with the plastic state of the coal, thermal decomposition of the coal takes place. The coking ability of a coal can be directly related to the plasticity of the coal. In liquefaction reactions, plastic coals tend to give higher yields than nonplastic coals, a fact very useful in the synfuel industry. Plastic coals, however, tend to agglomerate in fluidized bed reactors thereby impairing their function. Currently, the ASTM approved method used to determine plasticity is by means of a Gieseler plastometer. Gieselers are inconsistent; therefore, an easier and more efficient method is needed. A current and widely accepted idea is that the extractable portion of the mid-ranked coal is responsible for initiating the plasticity mechanism. It has been shown that plasticity can be correlated to the total aliphatic C-H content of a bituminous coal. This extractable portion is the bitumen in the coal. It is logical, then, to assume that the bitumen in the coal could be analyzed for the aliphatic content and be used as a predictor of plasticity. Tetrahydrofuran (THF) was used as the solvent for the Soxhlet extraction of 40 highly characterized bituminous coals. The extracts were purified and analyzed by Fourier Transform Infrared Spectroscopy and Proton Magnetic Resonance Spectroscopy.
10

Air Oxidation of a Soluble Coal Extract

Kimbler, Douglas 01 December 1989 (has links)
The effects of air oxidation on coal may change many important attributes of the coal such as calorific values, solubilities and solvent swelling values. By studying the effects of air oxidation on the soluble portion of coal, we were able to study coal oxidation in a new light.

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