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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.
191

Environmental Analysis of Full Depth Reclamation Using Coal Combustion By-Products

Mackos, Ryan Christopher 21 October 2008 (has links)
No description available.
192

Effects of lignosulfonate in combination with urea on soil carbon and nitrogen dynamics

Meier, Jackie N. January 1992 (has links)
No description available.
193

Influence of ammonium lignosulfonate fertilizer mixtures on corn (Zea mays L.) growth and nutrient composition

Russell, Elizabeth F. (Elizabeth Fiona) January 1992 (has links)
No description available.
194

A toxicity assessment of sludge fluids associated with tar sands tailings /

Abdel Warith, Mostafa January 1983 (has links)
No description available.
195

EFFECT OF STRATEGIC BLENDING OF FOOD INDUSTRY BY-PRODUCTS WITH PROTEIN SUPPLEMENTS ON PERFORMANCE OF GROWING AND FINISHING BEEF CATTLE

Bien, Richard Augustine Atedi 01 May 2024 (has links) (PDF)
The objective of this research was to evaluate the impact of strategical blending of by-products of pea protein extraction such as pea molasses (PMS) and pea starch and fiber (PSF) with canola meal (CM) or distillers dried grains (DDGS) on the growth performance, rumen fermentation, and total tract nutrient digestibility of beef cattle. Preliminary evaluation (study 1) involved 4 runs of in vitro and two runs of in situ to evaluate the rumen fermentation and nutrient degradation of strategically blended CM. The treatments included regular CM (CM), CM blends containing PMS and PSF at 5% (CM5) and 10% (CM10) levels in CM, 1.5% PMS in CM (CM+PMS) and 1.5% PSF in CM (CM+PSF) (% DM basis). The CM+PMS had greater (P < 0.05) DM and CP digestibility in vitro and in situ with significant total gas production, while the CM+PSF had lower methane per gram of DM. In study 2, a 56-d backgrounding and a 145-d finishing trial were carried out to evaluate the growth performance and carcass characteristics of growing and finishing beef steers fed diets containing strategically blended protein supplements. The treatments used were CM (CM), CM+PMS (PMS at 1.5% of CM DM), DDGS, and DDGS+PSF (PSF at 2% diet DM). There was no treatment effect detected during both backgrounding and finishing for overall ADG, DMI or gain:feed. There were numerical improvements in carcass characteristics, indicating likely improvements in carcass traits at a greater level of inclusion in the diets. Study 3 involved a metabolism study using cannulated beef heifers fed the same finishing diets as the feedlot study in a 4 × 4 Latin square design to evaluate the impact of feeding strategically blended protein by-products on rumen fermentation, total tract nutrient digestibility, and nitrogen balance. There was no variation in total tract nutrient digestibility evaluated. The DM, OM, and CP digestibility were numerically greater for heifers fed CM treatments than those fed DDGS treatments, while the NDF and ADF digestibility were numerically greater for the DDGS treatments. There was no treatment variation in rumen pH measurements. There was also no diet effect on nitrogen balance measured. The results of these studies indicate that the inclusion of PMS and PSF in the diet of beef cattle had no negative influence on the growth performance. Numerical improvements in carcass traits, rumen fermentation, and total tract nutrient digestibility indicate that the growth performance and carcass characteristics may be improved by these food industry by-products at a greater level of inclusion in the beef cattle diets.
196

Microchemical characterization of ash from fuel production

Brock, Melissa Kay 10 November 2009 (has links)
Millions of tons of ash and slag are produced each year as a result of energy production. This study looks at the mineralogy and textures in the ash resulting from the gasification of a 25% Passaic Valley sewage sludge, 75% Pittsburgh #8 coal slurry in a Texaco gasification facility and at ash resulting from the incineration of municipal solid waste at several facilities in Virginia and North Carolina. This information is then compared with similar studies done on ash and slag from coal-burning power plants and a study done on petroleum coke slag which was produced at a Texaco gasification facility. Lastly, a comparison of bulk chemistries of ashes to those of soil and crustal rocks is made. A general understanding of the stability of elements, especially metals, in terms of the phases in which they are contained as well as the textures, was hoped to be gained from this study. Samples for this study were polished sections which were 2.54 em in diameter that were set in cold-setting epoxy then ground and polished. Samples were then studied under a reflected light microscope before being carbon coated for study on a SEM and an electron microprobe. Photos of textures and analyses were made throughout. At least 50% of the ash from all sources was a Si-Al oxide rich glass which had varying amounts of Fe, Ca, K, P, Mg, and Ti and other trace elements. Fe oxides and spinels were common phases found. Pb and Zn were rarely encountered, but were found as both oxides and sulfides. Cr was found in the form of spinels, often covered by a protective AI enriched outer rim. The heavy metals found were successfully bound as mineral analogs or as a glass phase. The only phase found to be reactive was an AIC matrix containing subhedral SiC crystals. The AI phase effervesced when placed in contact with water, changing from tan to greenlblue/violet in color, releasing a gas (probably CO₂, C2H2, or CH4) in the process. / Master of Science
197

Removal of dissolved organic carbon and organic halide precursors by enhanced coagulation

Hargette, Paul Hudson 25 August 2008 (has links)
Raw water samples from nine utilities were received, and water-quality analyses, bench-scale water treatment, and chlorination were performed to determine the effectiveness of enhanced coagulation at removal of dissolved organic carbon (DOC) and organic halide precursors. Bench-scale treatment included: 1) baseline treatment, defined as the coagulant dose and pH at which the specific utility's water treatment plant was operating on the day the samples were collected, and 2) enhanced treatment, which was determined on the basis of bench-scale studies. Enhanced treatment is defined in the proposed Disinfectant/Disinfection By-Products (D/DBP) Rule as the coagulant dose at which a 10 mg/L increase in coagulant dose does not produce greater than a 0.3 mg/L decrease in dissolved organic carbon (DOC) or total organic carbon (TOC) concentration over the previous dose (Federal Register 1994). The treated samples were then chlorinated and analyzed for disinfection by-products (DBPs), including trihalomethanes (THMs) and non-purgeable dissolved organic halides (NPDOX). Specific objectives included: 1) an evaluation of the effectiveness of enhanced coagulation for TOC reduction, 2) determination of the effectiveness of surrogate parameters: such as raw water DOC and specific ultraviolet absorbance (SUVA); for predicting TOC removal by enhanced coagulation, and 3) determination of the relationship between DOC and NPDOX concentration in raw and treated waters. For all of the utilities, enhanced coagulation was effective at meeting the proposed TOC removal requirements contained in the D/DBP Rule, which range from 20 percent to 50 percent removal based on the alkalinity and TOC of the raw water. Raw water SUVA was the best indicator of the expected Toe removal by enhanced coagulation, with raw water SUVA values > 3.0 L/mg-m typically indicating greater TOC removal. Organic content was a good indicator of DBP formation. The average non-purgeable dissolved organic halogen formation potential (NPDOXFP) yields, based on DOC, were 155 μg as Cl⁻/mg DOC for raw water samples and ranged from 110- 138 μg as CI⁻/mg DOC for treated water samples. / Master of Science
198

Analysis of disinfection by products in drinking water by solid phase extraction

Sexton, Diane Lynne 12 September 2009 (has links)
The objectives of this research were to develop a broad spectrum method for the extraction, concentration, and analysis of drinking water disinfection by products using solid phase extraction (SPE), and to determine if this method had lower detection limits and less variability than the proposed liquid-liquid extraction method, EPA Method 551. The disinfection by products investigated were halogenated nitriles, ketones, and aldehydes. The SPE method extracted and concentrated samples using the C-18 Empore Extraction Disks, and desorbed the analytes with methyl-tert-butyl ether (MTBE) as a solvent. The results showed that with the SPE method the recoveries were low (0-50%) for most compounds, and the limit of detection (LOD) values were in the range of 0.2 to 50 ug/L, which were much higher than those for EPA Method 551. The variability was also higher than for EPA Method 551. The SPE method also appeared to be concentration dependent; the recoveries decreased as analyte concentration increased. Highly saline conditions (250 g/L NaCl) resulted in low recoveries and concentration dependencies for some compounds. Even though the SPE method was easier and faster, the lower method detection limit (MDL) values and lower variability made Method 551 more preferable. Further analysis of the SPE method using a new cyclohexyl disk was also recommended. / Master of Science
199

Effects of crab scraps on marine environments

Kramer, Teresa Anne January 1983 (has links)
M.S.
200

Effect of application of fluidized bed combustion residue to reclaimed mine pastures on forage yield, composition, animal performance and mineral status

Smedley, Kristi Olson January 1985 (has links)
Reclaimed surface mined soils in Appalachia are typically infertile and must be amended for optimum vegetative growth. Fluidized bed combustion residue (FBCR), a by-product of coal-fired power plants, has high levels of Ca, S, Zn, Fe, and Al, and 50% of the neutralizing capacity of limestone. Three treatments were applied to three replicated .81 ha reclaimed mine pastures: control (no amendment), 6760 kg FBCR/ha, and 3380 kg limestone/ha. Based on forage availability, six steers were rotationally grazed on pastures receiving each treatment. Steers were weighed and blood samples collected at 14-d intervals and all animals were sacrificed for tissue sampling at the end of the 114-d trial. Amendment with FBCR or limestone increased soil pH (P < .05) above control levels. Forage yield and steer gain were not significantly affected by treatment. Forage samples collected during the trial indicated that FBCR and limestone amendments elevated forage ash, Ca, Mg, S, Cu and Ca:P ratio (P < .05). Cellulose and NDF were depressed in forage grab samples collected from FBCR- and limestone-amended pastures. The forage sampled the following spring was lower in hemicellulose, Zn, un and Ni; and higher in ash, Ca, S, the Ca: P ratio in the FBCR- and limestone-amended pastures. Mean serum mineral levels of steers were not affected by pasture treatment. The blood packed cell volume was higher in cattle grazing FBCR-amended pastures. Liver levels of Fe, H, Hi and Na were lower in cattle on pastures amended with FBCR or limestone. Bile levels of Mn were depressed in cattle grazing FBCR~ and limestone-amended pastures. The level of Cu in the liver and serum was at deficiency levels and was not detectable in bile, regardless of treatment. Higher kidney levels of Ca, Hg and P were recorded for steers grazing FBCR- and limestone-amended pastures. Hair Zn was higher in cattle grazing the FBCR- and limestone- treated pastures. Rib Cr and long bone Cd levels were lower in animals grazing the limestone- and FBCR-treated pastures. This study suggests that FBCR amendment enhances nutrient quality of forage and mineral status of animals at least as well as limestone application to acidic reclaimed mine pastures. / Ph. D. / incomplete_metadata

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