• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 259
  • 227
  • 130
  • 64
  • 28
  • 26
  • 23
  • 7
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • Tagged with
  • 1311
  • 464
  • 453
  • 369
  • 367
  • 151
  • 137
  • 118
  • 114
  • 98
  • 86
  • 72
  • 72
  • 57
  • 55
  • 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.
391

Palladium (II) and platinum (II) complexes of cyanomethyl (diphenyl) phosphine and o-cyanophenyl (diphenyl) phosphine

Trujillo, Horeb 03 June 2011 (has links)
Cyanomethyl(diphenyl)phosphine (L) and o-cyanopheryl(diphenyl)phosphine (LI) react with H2PdX4 (X = Cl, Br) or K2PtCl4 to yield complexes of the type MX2E2(M = Pd, Pt; E = L, L'). Infrared and nuclear magnetic resonance spectroscopic data indicate that L and Ĺ are coordinated through the phosphorus atom, and that the Land L'-containing complexes have cis and trans geometries, respectively, The MC12E2 complexes react with potassium thiocyanate to yield derivatives of the type 1,(NCS):,L9, in which the thiocyanate groups are nitrogen-bonded to 'the metal.The reaction of L, L' or PdX2E2 (E = L or L') with either PdX2 (X = Cl, Br) or Na2PdX4, in a 1 to 1.1 mole ratio yields complexes of the type (PdX2E.)n. Infrared data indicate that the (PdX2L)n complexes are ligand- and the (PdX2L')n complexes halogen-bridged species.Ball State UniversityMuncie, IN 47306
392

Characterization of edaphic relationship of the Spicebush subcommunity

Cartwright, Kelly L. 03 June 2011 (has links)
The plant used in this study was the woodland shrub, Spicebush, Lindera benzoin (L.) Blume. Spicebush, is characteristically found on a poorly drained soil, within Beech-Maple or Mixed Mesophytic forests. It commonly occurs as pure stands in small patches within the shrub layer of mesophytic forests.The objective of this study was to characterize the soil type upon which Spicebush crows and to relate the soil-plant relationship in tears of establishment, growth, and development of the Spicebush. The variables used in accomplishing this objective were based on the physical and chemical regimes of Spicebush subcommunities. Ginn Woods, a climax beech-maple forest in Delaware County, Indiana, was used as a study area. Spicebush subcommunities within the woods were rapped and three representative sites were selected. The factors examined in the study were soil profile, soil moisture and temperature, soil and tissue levels of nitrate, phosphorus and the trace element metals Cr, Cu, Zn, Mn, Fe, Pb, Ni, and Cd. Analysis of the soil horizons was performed by soil core and visual characterization at the representative sites. Soil moisture blocks and temperature probes were buried at 5 centimeter and 20 centimeter depths at the sites for determination of soil temperature and available soil moisture. Data was collected at the sites every other day. Nitrate and phosphorus levels for plant tissue and soil were analyzed by the Kjeldahl Method and Spectrophotcznetric Method, respectively. An Atomic Absorption Spectrophotanetric Unit was used to determine amounts of ppm. of the metallic salts in samples of soil and leaf tissue.Ball State UniversityMuncie, IN 47306
393

Analysis of polyamines and serotonin by mass-analyzed ion kinetic energy spectrometry

Lloyd, Larry D. 03 June 2011 (has links)
Mass-analyzed ion kinetic energy (MIKE) spectra were obtained for serotonin and the polyamines. The predominant reaction observed was the loss of NH3 from the protonated species. The MIKE methodology was applied to the direct analysis of polyamines in bacteria without any sample preparation.Quantitative analysis was shown to be possible with deuterated putrescine as an internal standard.Ball State UniversityMuncie, IN 47306
394

The applied use of commercial UV units in cold storage rooms of local supermarkets

Dawson, Joyce V. 03 June 2011 (has links)
The purpose of this study was to evaluate the applied use of a commercial UV unit for air sanitation in the cold storage rooms of a local supermarket chain. On-site testing was performed in four supermarkets (two control stores without UV units and two experimental stores) and one warehouse employing UV units. Meat processing, meat storage, and produce storage rooms were randomly sampled by the open plate and swab methods. Commonly occurring "representative microorganisms" were then selected and identified as Pseudomonas sp., Flavobacterium sp., Bacillus sp., Rhodotorula sp., and Penicillium sp. which were taken into the laboratory for UV testing. Representative microorganisms were effectively killed by UV when tested in the laboratory. Exposure to UV was conducted on agar streaked plates and aerosol suspensions of the microorganisms. The effectiveness of the commercial UV unit in the applied setting was less easily determined due to a complexity of changing variables between rooms and between stores. In general, the UV unit appeared to be of noticeable benefit where airborne yeasts and molds were predominant. This occurred in produce rooms. Regular maintenance of the UV unit was necessary for maximum efficiency. The meat processing room presented unique problems relating to procedural habits of the personnel. In all supermarket cold rooms, good "housecleaning" remained the key to controlling microorganisms.Ball State UniversityMuncie, IN 47306
395

Design and Study of an NQR spectrometer for operaion at low temperatures

Albert, Frank David 03 June 2011 (has links)
This thesis begins with a theoretical description of the quadrupole nucleus, its interaction with a molecular electric field and its detection.The design parameters for the minaturized cryogenic NQR Spectrometer are presented along with an analysis of the operation of a superregenerative oscillator-detector. A review of the problems encountered in the development of the spectrometer is also presented.Ball State UniversityMuncie, IN 47306
396

Ligand properties of some phospine-nitrile systems

Worstell, Jonathan Harlan 03 June 2011 (has links)
3-Cyanopropyl(diphenyl)phosphine was synthesized from chloro(diphenyl)phosphine and 4-chlorobutyronitrile. This new ligand, along with (C6H5)2PCH2CN and (C6H5)2PCH2CH(CH3)CN were reacted with Re(CO)5X (X=Cl,Br) in 1:1 and 1:2.5 (metal:ligand) mole ratios.For all ligands, complexes with the stoichiometry Re(CO)3L2X were isolated from the 1:2.5 mole ratio reactions. Spectroscopic data suggest that the CO groups are facial and the ligands cis to each other.For all ligands, complexes with the stoichiometry Re2(CO)6L2X2 were isolated from the 1:1 mole ratio reactions. Spectroscopic evidence suggests that all the complexes are ligand bridged dimers which utilize the phosphorus and nitrogen lone pairs of the ligand.Ball State UniversityMuncie, IN 47306
397

Syntheses and reactivities of some cyanophosphine ligands

Saval, Ivan Harmodio 03 June 2011 (has links)
The ligands o-cyanophenyl(diphenyl)phosphine and bis(dimethylamino)(o-cyanophenyl) phosphine were synthesized from o-bromobenzonitrile and diphenylchlorophosphine and bis(dimethylamino)chlorophosphine, respectively. Both ligands were identified by IR, NMR and physical constant data. The reaction of bis(dimethylamino)(o-cyanophenyl)phosphine with sulfur or CH3I yields complexes of the stoichiometry [(CH3)2N]2(o-C6H4CN)P(X) (X=S, CH3I). NMR and IR spectral data suggest that the phosphorus is the site of reaction.Reaction of 2-cyanocyclohexyl(diphenyl)phosphine, 2-cyanocyclopentyl(diphenyl)phosphine or 2-cyanoethyl(dipheriyl)phosphine with M(CO)6 (M=Mo,W) and NaBH4 in refluxing ethanol yielded complexes of the stoichiometry M(CO4)L (L=2(aminomethyl)cyclohexyl(diphenyl) phosphine, 2(aminomethyl)cyclopentyl(diphenyl)phosphine, or 3-aminopropyl (diphenyl) phosphine). The infrared spectra of the complexes display two v(NH) bands at ca. 3360 cm-1 and 3308 cm-1 which are indicative of coordinated NH2 groups which result from the reduction of the CN groups. Four v(CO) bands are observed for the complexes which indicates that the compounds are of cis-configuration.Ball State UniversityMuncie, IN 47306
398

The use of the hand-held mirror as a patient education tool during routine pelvic examination / Preliminary title: Significance of mirror-assisted pelvic examinations to patient education

Fawcett, Robert S. 03 June 2011 (has links)
Eighty-one patients in Planned Parenthood at East Central Indiana participated in the study. All patients were given a short quiz concerning female anatomy at their intake evaluation. All patients participated in the routine patient education session and intake history. The experimental group (N=41) was given a mirror through which to watch the pelvic examination. The control group (N=40) was given the same sort of examination without the mirror. The quiz was then repeated.Pre-test results were identical in the two groups. Both groups improved significantly on the post-test compared to the pre-test, showing the patient education session to be an effective tool. The experimental group improved more than the control group, however, and the difference was significant at the P=0.06 level.It is concluded that pelvic examinations which routinely include a hand-held mirror through which the patient may visualize her own genitalia are of significant benefit as a patient educational tool.Ball State UniversityMuncie, IN 47306
399

Testing the performance of a water-type flat-plate solar collector in Muncie, Indiana

Tecle, Aregai 03 June 2011 (has links)
The flat-plate solar collector is the most commonly used device for the direct utilization of solar energy, but its applicability in some places is still debatable. The performance of the solar collector varies with changes in environmental and operational conditions. In this thesis the performance ice of a flat-plate solar collector was examined in order to determine the feasibility of utilizing solar energy s an alternative energy resource for residential water and space heating purposes in East Central Indiana.Various environmental and operational data pertinent to the performance of the solar collector were collected over a period of 76 days (March 26 through June 10). Analysis of the data showed that the efficiency of the collector varies with changes in climatic and operational conditions. Negative relationships were observed between efficiency and fluid inlet temperature, wind speed, cloud cover and precipitation, while relationships between the collector efficiency and ambient temperature, solar radiation and fluid flow rate were found to be positive. Further analysis of the collector performance findings and the average energy consumption in i-iuncie, Indiana produced encouraging evidence for the utilization of solar energy for residential crater heating and space heating purposes in the area.Ball State UniversityMuncie, IN 47306
400

An investigation of Fusarium roseum for the biological control of Hydrilla verticillata / Fusarium roseum for the biological control of Hydrilla verticillata.

West, Lynn Cousert 03 June 2011 (has links)
In laboratory tests, the plant pathogen Fusarium roseum demonstrated the potential to serve as a self-sustaining biological control for the noxious aquatic weed Hydrilla verticillata. At fungal spore concentrations of at least 1 x 104 spores per ml, the fungus induced chlorosis, growth inhibition, abscission, and stem disintegration of diseased hydrilla tissue and eventually resulted in death of the plant. The pathogenicity of the fungus was affected by pH, spore concentration, and the length of time after inoculation. Fusarium roseum reisolated from diseased hydrilla tissue readily infected fresh hydrilla plants. Histological studies demonstrated the presence of foreign bodies in the vascular portions of infected hydrilla, although the fungus itself was not observed growing in the plant tissue.Ball State UniversityMuncie, IN 47306

Page generated in 0.0465 seconds