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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.
81

Irrigation of Small Grains in Arizona

Ottman, Michael, Husman, Steve 09 1900 (has links)
6 pp. / Water use, critical soil water depletion, and irrigation scheduling for wheat and barley are explained in this publication.
82

High Rates of Sewage Sludge in Wheat Production

Day, A. D., Solomon, M. A., Ottman, M. J., Taylor, B. B. 09 1900 (has links)
A greenhouse experiment was conducted at the University of Arizona, Tucson, Arizona, to study the effects of sewage sludge loading rates on the vegetative growth, yield, and heavy metal contents of wheat grain and straw. Vegetative growth, grain and straw yields were similar whether wheat was fertilized with the recommended rate of inorganic N (112 kg/ha) or equivalent amounts of plant-available N from sewage sludge. Sewage sludge loading rates higher than three times the recommended plant- available N level delayed maturity and decreased wheat stands in the seedling stage; however, grain and straw yields were similar for all sewage sludge loading rates. Concentrations of cadmium (Cd), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in wheat grain and straw and in the soil following each harvest were low and similar for all fertilizer treatments.
83

Small Grains Variety Evaluation at Arizona City, Coolidge, Maricopa and Yuma, 2011

Ottman, M. J. 02 1900 (has links)
Small grain varieties are evaluated each year by University of Arizona personnel. The purpose of these tests is to characterize varieties in terms of yield and other attributes. Variety performance varies greatly from year to year and several site-years are necessary to adequately characterize the yield potential of a variety. A summary of small grain variety trials conducted by the University of Arizona can be found online at http://ag.arizona.edu/pubs/crops/az1265.pdf.
84

Wheat and Barley Varieties for Arizona 2011

Ottman, Michael J. 10 1900 (has links)
Revised / 2 pp.
85

Wheat and Barley Varieties for Arizona 2012

Ottman, Michael J. 12 1900 (has links)
Revised / 2 pp.
86

Interregional competition in the biorefinery industry

Clarke, Nathan January 1900 (has links)
Master of Science / Department of Agricultural Economics / Arlo Biere / A major story in the recent history of US agriculture is the evolution and growth of the ethanol industry. A crucial factor in the profitability of an ethanol plant is the choice of its fixed location, as this has implications in the transportation costs associated with the acquisition of grain and sale of distiller’s grains. When the industry was in its infancy, where to locate, often, was based on strictly local factors. Primary considerations were local availability of grain and producer and community investment interests. Today, the ethanol industry is more mature and consolidated. As such, investment criteria have broadened from a localized to a total systems perspective. The focus of this study was to analyze construction, abandonment, and expansion of plant locations in ethanol producing regions, and the effects of regional transportation costs on the geographic growth of the industry. Comparison to previous research provided the basis to evaluate industry change. Current ethanol plant locations and their capacities were complied and compared with earlier data to identify plant exits, expansions and new construction. Aggregating those plant capacities by USDA crop reporting districts, feedstock consumption by biorefineries were calculated by crop reporting district, as was livestock feed demand from livestock numbers. Those data along with coarse grain production by crop reporting district were used to calculate excess feedgrain demand (supply) by region. Those regional data were used to construct linear programming network-flow models for the transportation of feedstock and for DDGS, respectively. Two models were used; the first was used minimize the interregional cost to transport feedstocks from excess supply regions to excess demand regions. The second was used to minimize the interregional cost to transport DDGS from excess supply regions to excess demand regions. These regional transportation costs were combined to find the total interregional transport by crop reporting district. Differences in such interregional transport costs affect the competitiveness of plants across crop reporting districts and should affect the strategic position of each plant location. Current plant locations and transportation cost results were compared with those from previous research and, with additional consideration to changes in production factors, provided further understanding of the recent growth and development of the ethanol industry.
87

The evaluation of sorghum dried distiller's grains with solubles in nursery pig diets, on finishing pig performance and meat quality, and on lactating sow performance.

Sotak, Kelly Marie January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Robert Goodband / Five experiments were conducted to determine the effects of sorghum dried distiller’s grains with solubles (DDGS) on nursery pig performance, finishing pig performance and meat quality, and lactating sow and litter performance. Experiment 1 established a nutrient database and evaluated the quality and consistency of five ethanol plants in the Western Plains region. Each sample was analyzed for AA, DM, CP, crude fiber, crude fat, ash, NDF, ADF, Ca, P, trace minerals, GE, and starch. In addition, DE, ME, and NE were calculated. Experiments 2 and 3 evaluated the effects of sorghum DDGS on nursery pig performance. In Exp. 2, pigs fed sorghum- or corn-based diets performed similarly; however, as sorghum DDGS increased ADG decreased (linear, P < 0.01). A DDGS×grain source interaction (quadratic, P = 0.03) was observed for G:F. In corn-based diets, G:F was identical for pigs fed 0 to 30% DDGS, but worsened in pigs fed 45% DDGS. In sorghum-based diets, G:F was best for those fed 0% DDGS, but worsened at higher levels. In Exp. 3, pigs fed corn- or sorghum-based diets performed similarly; however, pigs fed DDGS gained less (P < 0.03) than those fed basal diets. Experiment 4 evaluated the effects of sorghum DDGS in sorghum- or corn-based diets on finishing pig growth performance, carcass characteristics, and fat quality. Increasing sorghum DDGS reduced (linear; P < 0.01) ADG and increased (linear; P < 0.01) backfat IV. Pigs fed the sorghum-based diet with 30% sorghum DDGS had decreased backfat IV (P < 0.01) than those fed the sorghum-based diet with corn DDGS. Experiment 5 evaluated the effects of sorghum DDGS on lactating sow and litter performance. Overall, ADFI increased in corn-based diets when DDGS were added, but decreased in sorghum-based diets resulting in a tendency (P < 0.08) for a DDGS × grain source interaction. Pig weaning weights were lower (P < 0.06) for sows fed diets containing DDGS compared with those fed the basal diets. Adding sorghum DDGS reduced pig performance, and sow lactation performance; therefore, its inclusion in swine diets needs to be evaluated on an income over feed cost basis.
88

Análise de um sistema de transporte ferroviário de granéis agrícolas através de uma abordagem integrada simulação-otimização. / A railroad transportation system analysis in a simulation-optimization framework.

Camargo, Pedro Veiga de 05 November 2010 (has links)
O transporte ferroviário é uma das mais eficientes formas para escoamento da safra brasileira de granéis agrícolas. Apesar disso, a malha ferroviária nacional, bem como a sua frota de veículos, não tem sido expandida no mesmo ritmo que a produção de grãos, impondo restrições de capacidade de transporte cada vez mais fortes nesse modal. Nesse contexto, é necessário que a ferrovia torne-se mais eficiente, de forma a suprir o seu crescimento deficitário com aumento de produtividade. Esse trabalho lança mão de uma abordagem mista simulação-otimização para realizar a análise de possíveis estratégias operacionais para um sistema de transporte ferroviário operando em ciclo fechado, abordagem que se mostrou bastante adequada à representação de sistemas ferroviários do tipo considerado neste trabalho. É apresentado um modelo de simulação estocástica implementado em linguagem de programação dentro do qual foram testadas diversas regras de decisão baseadas em figuras de mérito diversas, algumas das quais apresentando resultados bastante promissores para testes práticos. / Railway transportation is one of the most efficient means used to carry the Brazilian grain production to export ports. However, grain production has grown at a faster rate than the railway infrastructure, leading to several operational restrictions for this transportation mode. Therefore it is expected from the railway operators an increase in their efficiency to supplement their lack of capacity. This research presents a discussion of some strategies that could be used for a grain rail transportation system operating in a closed loop, which was modeled as an simulation-optimization type of model, which revealed itself a very suitable approach when modeling this type of transportation system. This dissertation describes the simulation model developed to characterize the system, the prioritization rules that were incorporated into the model, as well as some very promising results.
89

Variation and availability of nutrients in co-products from bio-ethanol production fed to ruminants

Nuez-Ortin, Waldo Gabriel 15 April 2010
The main objective of this project was to investigate the effects of the type of dried distillers grains with solubles (wheat DDGS, corn DDGS, and blend DDGS (eg. wheat:corn = 70:30)) and bio-ethanol plant origin on the nutrient variation and availability in ruminants. In addition, DDGS products were studied as opposed to their parental grains. The project was divided into the several following studies. In Study 1, we studied the nutritive value of DDGS products in terms of (1) chemical profiles, (2) protein and carbohydrate sub-fractions associated with different degradation rates, and (3) digestible component nutrients and energy values using the NRC 2001-chemical approach and the in situ assay-biological approach. Also, we tested the validity of acid detergent insoluble crude protein (ADICP) and acid detergent lignin (ADL) to predict the potential degradability of DDGS. Due to starch fermentation in the ethanol process, the chemical components in DDGS became approximately threefold more concentrated than in feedstock grains. Slowly degraded protein (PB3) and unavailable protein (PC) increased in DDGS, indicating a decrease in the overall protein degradability in the rumen. Intermediately degraded protein (PB2) was higher for corn DDGS than for wheat DDGS and blend DDGS (54.2 vs. 27.7 vs. 30.8 %CP), while PB3 was higher for wheat DDGS and blend DDGS (29.9 vs. 51.2 vs. 53.2 %CP). Mainly as a result of differing heat conditions, PC differed significantly between wheat DDGS originated at different bio-ethanol plants (0.7 vs. 7.6 %CP). The prediction of truly digestible CP (tdCP) and NDF (tdNDF) differed between the NRC 2001-chemical approach and the in situ assay-biological approach; however, both approaches reported similar energy values. These values were the highest for corn DDGS (DE3X: 3.9 Mcal kg-1), followed by blend DDGS (DE3X: 3.6 Mcal kg-1), and wheat DDGS (DE3X: 3.4 Mcal kg-1). Corn DDGS was superior to corn, wheat DDGS was similar to wheat and corn, and blend DDGS was similar to corn. No significant differences in energy values were reported between bio-ethanol plants. ADICP was not an accurate indicator of the potential degradability of protein in DDGS samples, while ADL seemed to be an acceptable indicator of the potential degradability of DM (r = -0.87; P<0.01), CP (r = -0.89; P<0.01), and NDF (r = -0.82; P<0.01) in wheat DDGS samples incubated in rumen during 48 h.<p> In Study 2, we studied the ruminal and intestinal digestion profiles and the hourly effective rumen degradation ratios between nitrogen (N) and energy. The results showed a reduction in the effective degradability of DM (EDDM), OM (EDOM) and CP (EDCP) of wheat DDGS relative to wheat; however, corn DDGS remained the same as corn. The effective degradability of NDF (EDNDF) did not vary between the DDGS samples and feedstock grains. Among DDGS types, EDDM ranged from 52.4 to 57.7 %, EDOM from 46.4 to 53.5 %DM, and EDCP from 34.0 to 45.6 %CP, being higher as the proportion of wheat in feedstock increased. No significant differences in EDDM, EDOM, EDCP and EDNDF for wheat DDGS were detected between the different bio-ethanol plants. The hourly effective degradability ratios between N and energy indicated a potential excess of N in rumen when DDGS samples were evaluated as single ingredient. This excess increased as the proportion of wheat in feedstock increased. Estimated intestinal digestibility of rumen bypass protein (IDP) was similar between wheat and wheat DDGS, but higher in corn DDGS than in corn. Blend DDGS had the highest IDP (93.9 %RUP). Due to the significantly different PC sub-fraction found in wheat DDGS originated at the different bio-ethanol plants, a large but numerical difference was detected in IDP (89.4 vs. 75.9 %RUP).<p> In Study 3, we used both the DVE/OEB System and the NRC 2001 Model to reveal the metabolic characteristics of DDGS protein and predict the protein supply to dairy cattle. The two models showed higher protein values (DVE or MP) for DDGS samples than for feedstock grains. The higher IDP for blend DDGS largely contributed to the higher protein value relative to wheat DDGS and corn DDGS (MP: 277 vs. 242 vs. 250 g kg-1 DM). Similarly, protein values differed significantly between the bio-ethanol plants mainly as a result of the numerical but large difference in IDP (MP: 272 vs. 223 g kg-1 DM). According to the two models, the degraded protein balance for DDGS products was higher than in the parental grains. Wheat DDGS showed the highest potential N excess (DBPNRC: 78 g kg-1 DM). For corn DDGS, however, the DVE/OEB System suggested a potential N excess (11 g kg-1 DM) while the NRC 2001 Model exhibited a potential N deficiency (-12 g kg-1 DM). The degraded protein balance for wheat DDGS was similar between the different bio-ethanol plants.<p> In conclusion, the chemical and biological characteristics of DDGS varied among types and between wheat DDGS samples manufactured at the different bio-ethanol plants. Thus, it is inappropriate to assume fixed values for the nutritive value of DDGS without considering factors such as type of grain used and bio-ethanol plant origin. Further research with higher number of samples will help to clarify the use of the chemical profile to predict energy values and the potential degradability of DDGS.
90

Singing sands, musical grains and booming sand dunes

Patitsas, A.J. 14 July 2008 (has links)
The origin of the acoustic emissions from a bed of musical grains, impacted by a pestle, is sought in a boundary layer at the leading front of the pestle. The frequencies of the shear modes of vibration in such a layer are compared with the observed frequencies. It is assumed that such a layer is the result of the fluidization of the grain asperities due to the high stress level at the front end. Such a boundary layer can also account for the emissions from plates of sand sliding on a dune surface and from grains shaken in a jar.

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