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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.
21

Temperature and velocity profile functions in a free convective liquid metal system with volume heat source

Skavdahl, Richard E. January 1957 (has links)
Thesis (M.S.)--University of Michigan, 1957.
22

Analise basica e comparacao das caracteristicas do GCFR e LMFBR com o ciclo do torio pela teoria de difusao em grupo de energia

SABUNDJIAN, GAIANE 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:30:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 1 01068.pdf: 4318760 bytes, checksum: 8eb4e0a57ec79f8da29124496f7cd8cd (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
23

Analise basica e comparacao das caracteristicas do GCFR e LMFBR com o ciclo do torio pela teoria de difusao em grupo de energia

SABUNDJIAN, GAIANE 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:30:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:55Z (GMT). No. of bitstreams: 1 01068.pdf: 4318760 bytes, checksum: 8eb4e0a57ec79f8da29124496f7cd8cd (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
24

Evaluation of Feeding Varying Levels of Digestible Lysine on Broiler Breeder Male Reproductive Characteristics and Body Weight Changes

Obi, Chinwendu Nkechi 15 December 2012 (has links)
A preliminary test was conducted evaluating the effect of digestible lysine (dLys) on broiler breeder (BB) male semen quality from forty-one to forty-nine wk of age. Five dietary treatments: corn-soybean meal diet with 1,000 mg dLys/rooser/day (Soy1,000), distillers dried grains with solubles diet with 1,000 (DDGS1,000), 850 (DDGS850), 700 (DDGS700), and 550 (DDGS550) mg dLys/rooster/day. Semen quality was similar except percentage dead sperm which was higher in DDGS550. A second trail was conducted using the same dietary treatments as the preliminary test during twenty to thirty-nine wk of age. Semen quality was similar except percentage dead sperm which was higher in Soy1,000. Soy1,000 exhibited higher body weight (BW), breast weight, and plasma testosterone. In conclusion dLys levels from 1,000 to 700 mg/rooster/day will not adversely affect semen quality of BB males. Attention should be given to BW in BB as it could lead to an increased percentage dead sperm.
25

Evaluation of Varying Digestible Lysine Levels on the Reproductive Parameters of Cobb 500 Broiler Breeders and the Performance of their Progeny

Mejia, Leonel 12 May 2012 (has links)
The effect of decreasing digestible lysine (dLys) intake by broiler breeder (BB) hens from 35 to 45 wk of age on their reproductive performance and performance of their progeny was evaluated. Two types of diets were fed: a diet from commercially available ingredients consisting of dLys intakes of 1,200 (IDL) and 1,010 mg/hen/day (ID) and a semi-purified diet with dLys intakes of 1,010 (SPL) and 600 mg/hen/day (SP). Hens fed the SPL and SP diets had lower hen-day egg production compared to BB hens fed the IDL and ID diets. Fertility and hatchability of eggs set were lowest (P <0.05) for hens fed the SPL diets. Chick weight at hatch was lower (P<0.05) for those that came from the SP and SPLed hens, but 42 and 56 day body weights (BW) were similar for all treatments. Marginal improvements (P<0.10) in FCR were seen at 42 and 56 days for chicks from IDed hens compared to IDL hens. A decrease in daily intake of dLys appeared to improve BB reproductive performance when hens were fed a semi-purified diet and the same response was not observed in hens fed a diet from commercially available ingredients. Furthermore, the progeny study revealed marginal improvements in some live performance parameters. In a second study, a diet based from corn-soybean meal and formulated to a dLys intake of 1,000 mg/hen/day (CS) and three diets composed primarily of corn, soybean meal, and DDGS with 1,000 (DDGS-1,000), 800 (DDGS-800), and 600 (DDGS-600) mg of dLys/hen/day were fed to evaluate the reproductive performance of BB hens from 24 to 42 wk of age. Feeding diets composed of commercially available ingredients with dLys intake levels below 1,000 mg/hen/day did not impact BB reproductive performance. Reduced BW, carcass and breast weight, and higher (P<0.05) back half weight at 42 days of age was observed from broilers that came from 26 wk old BB hens fed the DDGS-600 diet. Reducing dLys intake in later BB hen ages did not impact progeny performance or carcass characteristics. This suggests that Lys may be in dietary surplus concentrations for commercial breeders under current practical conditions.
26

Investigation of fuel cycle for a sub-critical fusion-fission hybrid breeder reactor

Stewart, Christopher L. 13 January 2014 (has links)
The SABR fusion-fission hybrid concept for a fast burner reactor, which combines the IFR-PRISM fast reactor technology and the ITER tokamak physics and fusion technology, is adapted for a fusion-fission hybrid reactor, designated SABrR. SABrR is a sodium-cooled 3000 MWth reactor fueled with U-Pu-10Zr. For the chosen fuel and core geometry, two configurations of neutron reflector and tritium breeding structures are investigated: one which emphasizes a high tritium production rate and the other which emphasizes a high fissile production rate. Neutronics calculations are performed using the ERANOS 2.0 code package, which was developed in order to model the Phenix and SuperPhenix reactors. Both configurations are capable of producing fissile breeding ratios of about 1.3 while producing enough tritium to remain tritium-self-sufficient throughout the burnup cycle; in addition, the major factors which limit metal fuel residence time, fuel burnup and radiation damage to the cladding material, are modest.
27

DYNAMIC SIMULATION OF A SODIUM-COOLED FAST REACTOR POWER PLANT

Shinaishin, Mervat Abdel Monem, 1945- January 1976 (has links)
No description available.
28

The evaluation study of Mashashane breeder farms and hatchery project.

Kganyago, Tshoshane Gladys 12 1900 (has links)
Thesis (M.Ed)--University of Limpopo,2009. / This report describes the research carried out at both the Mashashane Breeder Farms and Hatchery Project established at Newlands village (Mashashane), of Polokwane Municipality of the Capricorn region of Limpopo Province in South Africa. This research is about the sustainability of projects in Limpopo Province of South Africa. For this purpose, the Mashashane Breeder Farms and Hatchery Project is the case of this study. The study aimed at evaluating the sustainability of the Mashashane Breeder Farms and Hatchery Project, so as to make authorities aware of the difficulties experienced in sustaining projects, and to highlight those factors that make projects succeed. The following research questions were formulated for this study: • What are the critical factors that determine sustainability of projects? • What can be the role of adult education in this project? The intention of this study was to investigate why most projects collapse; and what kept the Mashashane Breeder Farms and Hatchery Project to exist for such a long time. In Chapter 2 of this study, I formulated assumptions about the sustainability of projects. I suggested certain factors to be considered for the purpose of sustaining a project. My assumptions were needs analysis; organising people; communication; competition; management; deliverables; lack of skills; ability to plan; project ownership and participation; the role of the government; and time table (schedule). In Chapter 3, the methodology is outlined. This study followed the qualitative approach. Instruments used for the collection of data are also explained. I discussed the main learning area, outlined the difficulties in carrying out the research activities and concluded the chapter by the model of data matrix. In Chapter 4 of this study, findings from Mashashane Breeder Farms and Hatchery Project are outlined, based on documents, interviews and observations of activities of the project. I formulated variables informed by Chapter 2 of this study. I report on the setting of the Mashashane Breeder Farms and Hatchery Project. In Chapter 5, I have outlined conclusions based on the study. The suggested points about a good project are tabled. Inclusive of the challenges faced by the Mashashane Breeder Farms and Hatchery project are, namely: mortality; infertility; no income period; and education and training of employees. In Chapter 6, I have given recommendations for this study. Some of the recommendations specifically for this project are, namely: more projects should be established to address unemployment and poverty; feedback should be given to employees; communication should be reciprocal, prior work experience be recognised; adult education should be introduced for employees to upgrade their skills and develop some; workshops should be arranged to improve lives of employees; and increasing production and competition is to be encouraged at all levels (internally and externally).
29

Barley silage effects on poultry behaviour

Johannson, Sarah G. 28 April 2008
A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.
30

Barley silage effects on poultry behaviour

Johannson, Sarah G. 28 April 2008 (has links)
A series of trials were conducted to determine the effect of feeding barley silage to laying hens and broiler breeder pullets on performance, stress and behaviour. In the first study, two trials were conducted each with 20 hens and 2 roosters (n=176) randomly assigned to one of 8 community cages. The birds in 4 cages were provided with a nutritionally balanced soy/wheatbased laying hen diet ad libitum, whereas the birds in another 4 cages were given free access to barley silage in addition to the regular laying hen diet. In both trials, the control birds consumed more feed (P < 0.05) than the birds given barley silage. Birds fed barley silage had significantly decreased (P < 0.05) aggressive and feather pecking behaviours as well as time spent in their nest boxes at different ages. Time spent drinking, resting, preening and eating a large particle calcium source was similar between the two treatments. No treatment effects (P > 0.05) were found in regards to egg quality, egg production and bird weights at various ages; however yolk colour was darker by silage treatment in each trial. At the end of each trial, the feather score was improved in silage-fed birds compared to the control birds. It was concluded that feeding barley silage as a supplement to laying hens can improve their welfare without negatively affecting the egg production and egg quality. <p>A second study was conducted to determine the effect of feeding barley silage on body weight, stereotypic behaviour, stress and fear on broiler breeder pullets during the brooding and rearing periods. The 3 week old broiler breeder pullets (n=180) were randomly allocated into 12 straw litter floor pens having 15 birds per pen. The birds in 6 pens were provided with a nutritionally balanced corn/oat-soybean/canola meal-based broiler breeder diet at recommended restricted levels, whereas the birds in another 6 pens were given free access to barley silage in addition to a regular broiler breeder diet. Total DM intake was significantly higher (P < 0.05) for silage-fed birds compared to their control counterparts without affecting mean body weights. Dietary treatment had no significant effect on bird behaviour with the exception of object pecking behaviour which was reduced with silage feeding. Aggressive and gentle feather pecking behaviour was consistently numerically higher in the control birds than the silage-fed birds, although not significantly. Age affected many of the behaviours recorded in this study. Silage feeding had no significant effect on heterophil to lymphocyte ratios and tonic immobility values indicating that birds in both treatments were not very stressed or fearful. It was concluded that feeding barley silage to broiler breeder pullets has potential to aid in improving their welfare.

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