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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.
91

A study of activation analysis capabilities of the neutron generator with a tritium target in determing the source of certain drugs

Presdorf, Ronald L. 03 June 2011 (has links)
This study was an evaluation of the applicability of the neutron generator in identifying the manufacturing sources of drugs by studying; trace elements present in drug samples. The motivation w1as the possible assistance to law enforcement agencies in tracing illicit drugs to their origins.Eight samples of dextroamphetamine sulfate were used in the evaluation process. The samples were activated with a neutron generator producing a 14MMeV neutron flux of the order of 1010 neutrons/sec/cm2. A pair of NaI detectors and a multichannel analyzer were used to study, the decay spectra of the samples.The analytical system was found in most cases to be quite capable of detesting elements which were present in a few parts per million. Little success was encountered in detecting elements present at levels commonly considered to be trace amounts. Phosphorus, silicon, sodium, iron, and strontium where found in amounts ranging from 65 to 250,000 parts per million.Ball State UniversityMuncie, IN 47306
92

A chromatographic investigation of sub-speciation in Asclepias tuberosa

Canne, Judith M., 03 June 2011 (has links)
A study was made of subspeciation in Asclepias tuberosa using descending paper chromatography. An attempt was made to characterize the three subspecies of Asclepias tuberosa on the basis of amino acid and phenolic patterns.The amino acid patterns were of little value for differentiating the subspecies.The fluorescent phenolic compounds of Asclepias tuberosa were analyzed by placing the chromatograms under longwave ultraviolet light and under longwave ultraviolet light in the presence of ammonia vapor.The patterns of the three subspecies produced under ultraviolet light and under ultraviolet light in the presence of ammomia vapor showed identifying markers for each of the three subspecies. Hybrid plants were also distinguished.Ball State UniversityMuncie, IN 47306
93

A biosystematic study of Athyrium pycnocarpon compared to Athyrium thelypeteroides

Cumo, Joseph M. 03 June 2011 (has links)
This research has examined the phylogenetic relationship between the questionable Athyrium pycnocarpon and the valid Athyrium thelypteroides. Classical taxonomic data were reported to illustrate the sources of confusion in the phylogenetic positioning of the fern in question. Chromatographic analyses of biochemical secondary constituents were reported. Descending paper chromatograms, ascending thinlayer chromatograms and cellulose-acetate electrophoretograms were the three analytical tools used to develop the secondary compounds. Ultraviolet light and ninhydrin visualization of the separated secondary constituents produced characteristic spotting patterns. On the basis of the close similarities of all patterns between the Athyrium pycnocarpon and Athyrium thelypteroides, it was concluded that the Athyrium pycnocarpon is unquestionably a member of the Athyrium complex.Ball State UniversityMuncie, IN 47306
94

Determination of stellar temperatures

Long, Patrick D. 03 June 2011 (has links)
This study was an attempt to determine the temperature of select stellar bodies. Spectral data was to be obtained using a compensated vacuum thermocouple, a 10-inch Newtonian reflector, a current galvanometer, and select filters. Effective temperatures were to be calculated using the spectral data collected, Planck's radiation law, and bolometric theory. No stellar radiation measurements were taken because the galvanometer was not sensitive enough to detect current produced by the thermocouple when it was illuminated by stellar radiation.After the unsuccessful attempt to measure stellar radiation data was collected for radiation from 0.8425 of the radius of the sun's disk. Ratios for the intensity of radiation for three spectral components was found as follows; 0.48 for λ = 0.43 μ (blue ); 1.35 for λ = 0.525 μ (green); 0.88 for λ = 0.825 μ (red-infrared). water cell radiation measurements were also taken to provide relative energy information. The water cell measurements show that the sun transmits approximately 51% of its energy in the visible an ultraviolet spectrum.Ball State UniversityMuncie, IN 47306
95

Measurement of ionization in nuclear emulsion by lacunarity technique

Mueller, W. David 03 June 2011 (has links)
This thesis explored "lacunarity" as a technique for measuring ionization and energy loss of charged particles in nuclear emulsion. Lacunarity is defined as the fraction of a track segment that consists of gaps. A comparison was made between lacunarity and other methods of measuring ionization, particularly the method of measuring blob density. The nuclear emulsion used was exposed to a one GeV/C K- -meson beam.produced by the accelerator at the university of California at Berkeley. Proton, K – meason, π – meson and muon tracks emanating from “stars” or sites of nuclear disintegration were used as bases of study. The procedure was to plot grain density as determined by lacunarity of a track segment as well as blob density versus residual range for the various particles. This student found that except for tracks of very heavily ionizing particles or of very lightly ionizing particles, lacunarity is a better measure of ionization and energy loss than is blob density.Ball State UniversityMuncie, IN 47306
96

The effect of a complex pollutant on the cell count of cyanophyta in Little Lick Creek

Spinner, Ronald W. 03 June 2011 (has links)
Selected physicochemical properties of Little Lick Creek, in Hartford City, Indiana, were determined in the fall of 1969. Subsurface samples from five stations, two upstream and two downstream from a discharge point: at the. Minnesota Mining and Manufacturing Companywere analyzed. A complex effluent containing a dye entered the creek from the paper plant. Dissolved oxygen and biochemical oxygen demand determinations of the water downstream from the discharge displayed changes in water quality of the creek. The water temperature rose significantly after the discharge water entered the creek. A cell count study of the Cyanophyta of the creek was also determined.Little Lick Creek was considered polluted below the paper products plant discharge based on the observed changes in the water tested. Cyanophyta populations were apparently reduced by the effluent.Ball State UniversityMuncie, IN 47306
97

The effects of acridine on minute mutants of bacteriophage T4

Whitaker, William J. 03 June 2011 (has links)
Wild-type and minute mutants of the T4 strain of bacteriophages were treated with 1.0-12.0 ug per ml concentrations of aminoacridine. Escherichia coli was the host organism for the bacteriophages.Concentrations of acridine less than 2.0 ug per ml had no noticeable effect on wild-type ormmutant plaque formation. Two and one half to seven ug per ml concentrations of acridine reduced the size (diameter) and number of plaques formed from both. Concentrations greater than 7.0 ug per ml completely inhibited the growth of both.The host organism (Escherichia coli) was not affected by the acridine.Ball State UniversityMuncie, IN 47306
98

Tumor cell mitotic incidence in mice pretreated with autochthonous and syngeneic incoula

Stovall, William E. 03 June 2011 (has links)
Tumor bearing mice pre-treated with autochthonous and syngeneic inocula were found to have an enhanced immune response. Mitotic indices of the tumors from three experimental groups were significantly lower than those of the two control groups. The treated control group which received Freund's adjuvant also had a significantly lowered mitotic index, but was still significantly higher than the three experimental groups.The immune response was evidenced by reticuloendothelial involvement and anaphylactic reactions in various animals. Abnormalities found in the livers consisting of portal infiltration of reticular calls and megakaryocytes were observed. The tumor sections observed showed increased lymphocytic infiltration,There were no significant differences in the mitotic indices between the syngeneic and autochthonous recipients. A lack of antigenic differences in the tumors utilized is thus indicative of this finding.Ball State UniversityMuncie, IN 47306
99

The bactericidal effect of low ozone concentrations on experimentally airborne Aerobacter aerogens, Bacillus megatherium, and Escherichia coli B

Techy, Geza B. 03 June 2011 (has links)
AbstractThe bactericidal effect of ozone at concentrations of 1 and 2 p.p.m. by volume, was tested on separately atmized resting cell suspensions of Aerobacter aerogenes, Bacillus megathreium, and Escherichia coli B impinged on Millipore filters. The exposure of each species required the use of 18 randomly selected filters containing impinged organisms. Of the 18 filters, 6 were used in the control. The temperature and the relative humidity of the ozone flow were approximately 25ºC and 20 per cent, respectively, while the flow-rate across each filter was 3 liters per minute. It was found that all of the organisms tested were completely destroyed by both 2 and 2 p.p.m. ozone within 2 minutes of exposure.Ball State UniversityMuncie, IN 47306
100

Syntheses and decomposition of 3-vinyl-1-pyrazolines

Garrison, Joseph 03 June 2011 (has links)
A versatile method for the reduction of 2-pyrazolines was developed in this research. In every reduction attempt, aluminum trihydride successfully reduced the carbonnitrogen double bond. Since carbon-carbon double bonds were stable to aluminum trihydride, the preparation of 3-vinyl1-pyrazolines by a new synthetic route became possible. Using this method, 3,3-dimethyl-5-(1-isobutenyl)-1-pyrazoline was prepared. This compound was thermalytically decomposed, and the products of the decomposition were determined.In the course of this research, a one-step method for the preparation of cyclopropanes in high yield from 2pyrazolines was uncovered, but not fully developed. A new route to alpha-gamma-diamino compounds was also accomplished with the use of aluminum trihydride.Ball State UniversityMuncie, IN 47306

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