Demand for organic food products has grown at rates as high as 20% since the 1990s. Organic grains compose 11% of total organic food demand, and are used in livestock production which represents 43% of organic food demand. Though the demand for organic grains is arguably increasing, domestic production of organic grains is lagging. Producers in the U.S. are hesitant to transition to certified organic grain production for a number of reasons. However, a lack of information pertaining to the organic grains market is one of the most prominent barriers to entry. One method that may provide insight into marketing opportunities available to organic grain producers is to create classifications of organic grain buyers. These classifications may allow for the comparison of business demographics, perceptions of the organic grain market, relationship formation and maintenance factors, and characteristics of purchasing agreements across buyer classifications. These comparisons would allow producers to identify potential marketing opportunities by providing insight regarding types of assistance offered by buyers, how to form a relationship with buyers, types of purchasing agreements used, and purchasing agreement characteristics and requirements. Producers would then be able to identify appropriate buyers for their respective situations based on times contracts are signed, payment timing, storage and transportation requirements, and the amount of organic practice documentation buyers require. Similar classifications have been proposed for organic producers, but, to date, no such classification exists for organic buyers. This work proposes two classifications of organic buyers. First, a classification of committed organic buyers versus pragmatic organic/pragmatic conventional buyers is motivated by similar classifications of organic producers found in previous works. Secondly, this work also introduces a classification of buyers that are sellers versus end-users of organic grains. Literature has suggested that the type of organic grain buyer (seller or end-user) gives rise to differences in functionality regarding interacting with producers and purchasing agreement characteristics. A sample of 45 organic grain buyers in the Midwest was utilized to characterize business demographics, perceptions of the organic grain market, relationship factors, and purchasing agreement characteristics on the two aforementioned categorization of organic grain buyers. A mixed methodology approach was utilized involving data collection via phone interviews and an online questionnaire. Initial data analysis suggests that data from the two data collection methods statistically differed in some measures of business demographics, perceptions of the organic grains market, and types of assistance offered to producers. This suggests that buyers responding to a phone interview may be more willing to assist producers and have more positive perceptions of the organic market. Thus, each analysis separates phone interview and online questionnaire responses. Due to a small sample size, means comparisons were utilized for the proposed categorizations of buyers. Data were found to not adhere to the normality assumption, requiring the use of nonparametric methods. A Chi-square test was conducted for binary variables, while a Wilcoxon-Mann-Whitney test was utilized for continuous and categorical variables. Results suggest that committed organic grain buyers are smaller in terms of gross sales than pragmatic organic/conventional buyers. Fewer committed organic grain buyers require the grain supplier to pay for grain delivery when compared to pragmatic buyers. Both the comparison of committed organic versus pragmatic buyers and the comparison of sellers versus end-users suggest that there is a bifurcation in organic grain buyers, indicating potential conventionalization within the organic grain industry. Additionally, both categorizations also indicate the buyers anticipate future supply and demand to both increase, but do not expect future price to increase. Thus, it can be concluded that buyers believe future supply will increase at a greater rate than demand, decreasing price. Alternatively, buyers may expect future supply and demand to grow proportionally, keeping price constant. Though the sample is representative of the population of buyers present, the small sample size suggests results of this work should be interpreted with caution.

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In this study, firstly, in order to achieve fine grains in solid solution strengthened AZ31 magnesium alloy by friction stir processing (FSP), various efforts have been made. It has found that with a newly designed cooling system, the microstructure of commercial AZ31 alloy can be refined dramatically by carefully controlling the FSP parameters. It is of scientific interest that nanometer grains have been observed in the resultant microstructure for the AZ alloy experienced by two-pass FSP. Besides, in order to modify the microstructure and mechanical properties, FSP is also applied to incorporate AZ31 Mg alloy with nano-ZrO2 particles, nano-SiO2 particles and different fractions of Al and Zn elements. The microstructure and mechanical properties of the modified alloy and composite samples are investigated and compared. By one-pass FSP coupled with rapid heat sink from liquid nitrogen cooling approach, the ultrafine grain size in AZ31 Mg alloy is successfully achieved. The grain boundaries are well defined and the mean grain size can be refined to 100~300 nm from the initial 75 £gm of commercial AZ31 Mg alloys sheets. The ultrafine grained structure can drastically increases the microhardness from the initial 50 up to 120 Hv, or an increment factor of 2.4 times. Furthermore, the nanometer grains can be even achieved by two passes FSP coupled with rapid heat sink. The resulting microstructure exhibits equiaxed grains ranging from 40 nm to 200 nm with an average grain size of less than 100 nm. The nanocrystalline grains can be characterized by the TEM observations and the diffraction rings in SAD patterns. The highest hardness point can reach ~150 Hv which is equal to triple of the AZ31 matrix, and the mean hardness also increases up to around 134 Hv. Bulk Mg-AZ31 based composites with 10~20 vol% of nano-ZrO2 particles and 5~10 vol% of nano-SiO2 particles are also successfully fabricated by FSP. The average grain size of the resultant composites could be effectively refined to 2~4 £gm, and it demonstrates much higher hardness values compared to commercial AZ31 billet. Moreover, for the Mg/ZrO2 composite fabricated by one pass and subsequent cooling pass FSP, the recrystallized grain size could be further refined to 0.4 £gm with the hardness value of 135 Hv. As for multi-element Mg base alloys fabricated by FSP, high fractions of Al and Zn elements can result in apparent grain refinement, this can be proved by the broadening of diffraction peaks. Multi-passes FSP can induce the appearance of intermetallic compounds, however, some of them are quasi-crystals with icosahedral point group symmetry. The average hardness of the resultant alloys reachs nearly 350 in Hv scale due to the generation of intermetallic compounds and grain refinement.

Dynamic abnormal grain growth (DAGG) in commercial-purity molybdenum sheets was investigated through a series of tensile tests at temperatures between 1450°C and 1800°C. DAGG is abnormal grain growth (AGG) which requires the presence of concurrent plastic strain. Most AGG phenomena previously documented in the literature can be categorized as static abnormal grain growth (SAGG) because they occur during static annealing, sometimes following plastic strain, but do not occur during plastic deformation. The DAGG boundary migration rate is much faster than the SAGG boundary migration rate, and DAGG may be utilized to obtain large single crystals in the solid state. Dynamic abnormal grains were found to exhibit a crystallographic orientation preference with respect to the specimen geometry, generally described as derivative from a <101> fiber texture. DAGG was found to prefer growth on the surface of the specimen rather than the interior. The growth of dynamic abnormal grains, which initiated and grew during plastic straining, generally ceased when the application of plastic strain was removed. The DAGG boundary migration rate was found to be a direct function of plastic strain accumulation, regardless of the strain-rate. Therefore, it is hypothesized that the rapid boundary migration rate during DAGG results from an enhanced mobility of certain boundaries. A model is proposed based on the rate of boundary unpinning, as mediated by the emission of dislocations from pinning sites. / text

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Sociology, 2008. / Includes bibliographical references.

Master of Science / Department of Grain Science and Industry / Carlos Campabadal Teran / The use of grain aeration as a tool to minimize post-harvest losses requires lower ambient temperature (≤ 20°C) and relative humidity (≤ 70%) conditions than what is usually available during the summer season in temperate climates and throughout the year in some tropical climate regions. Warm and moist conditions contribute to pest problems and increase dependence on chemical control for pest reduction as part of grain management strategies. The grain chilling technology is a non-chemical alternative to cool grain stored under high risk climatic conditions. For this research project, the grain chilling technology was tested in a 1,350-ton low moisture content wheat silo during the 2015 and 2016 summer harvests in Kansas. The grain temperature was lowered from a maximum of 39°C to a minimum of 17°C in less than 250 hours. The results showed that chilled grain maintained at temperatures under 20°C reduced the development rate of insect pests compared to grain stored at temperatures over 25°C and cooled with ambient aeration. However, the cost of grain chilling was calculated to be between 0.26 and 0.32 $/t higher than using ambient aeration. Through computer simulation it was possible to evaluate the performance of the grain chiller against four different ambient aeration strategies for paddy rice stored under the tropical climatic conditions of the North Pacific coast of Costa Rica. After six months of storage, the minimum grain temperature achieved through ambient aeration was 30.8°C using an aeration strategy based on a grain-ambient temperature differential greater than 10°C. Grain chilling lowered the average grain temperature from 35°C to below 15°C in 117 hours and the maximum average temperature it registered after six months of storage was 15.5°C. The economic evaluation of the simulated ambient aeration and chilling strategy determined that the operational costs of grain chilling were between 2 and 4 $/t lower than ambient aeration plus fumigation. However, the initial cost of the grain chiller made the net present cost (NPC) of the chilling strategy between 0.22 and 0.85 $/t higher than the cost of ambient aeration plus fumigation over a 10-year analysis. Several potential financial options were analyzed to make the grain chiller more economically feasible for a rice miller in Costa Rica. It was concluded that the grain chilling technology can reduce grain temperatures below 20°C in a relatively short period of time, which helps control insect populations and maintain grain quality during summer storage in temperate climates and in tropical climates. Utilizing grain chilling reduced operational costs between 78% and 88% when compared to using chemical control of pests. Additionally, it was determined that an initial cost of $74,700 for the grain chiller would require a 16% discount or at least 10,641 t to be chilled annually to make this technology viable for the Costa Rican rice milling industry. Leasing the grain chiller (ten equal payments of $10,926) or adding a premium sell price of 1 $/t to chilled rice would make this technology feasible compared to the traditional grain management strategies utilized in Costa Rica.

Grain shippers are constantly faced with making merchandising and logistical decisions while trying to achieve a positive net margin. They have to decide how much grain to sell and when the most opportune time to do so occurs. In addition, decisions regarding how much freight should be acquired and where grain should be shipped need to be addressed. These decisions are met by several sources of risk such as futures spreads, basis levels, transit times, equipment placements, and farmer deliveries. The primary objective of this thesis was to develop a model to determine both the optimal amount of grain that should be sold in the pipeline and the optimal amount of freight that should be hedged by grain shippers through the use of forward shipping mechanisms. Certificates of Transportation (COTs) offered by the Burlington Northern Santa Fe (BNSF) Railway were used to represent forward shipping mechanisms in this thesis. A stochastic simulation model of a prototypical grain shipper containing three country elevators and two export facilities was developed. A sensitivity analysis was conducted on merchandising and logistical variables to evaluate different scenarios. The analysis revealed that committing to too many shuttle COTS limited the shipper's flexibility, forced sales to be made in suboptimal periods, and significantly increased the level of demurrage. The type of freight ordering strategy implemented by each elevator ultimately determined the overall sustainability of the firm; shippers need to diversify the type of freight they commit to because ordering too much long-term freight can result in bad sales decisions, whereas relying only on short-term freight is costly and inefficient. Not being able to quickly adapt to volatile market conditions can result in making bad selling decisions and untimely freight purchases which can hinder the longevity of a firm.

No description available.

Master of Science / Department of Food Science / Jon Faubion / There is evolving evidence that intake of whole grains protects against development of chronic diseases. Increasing the appeal of whole grain products proves difficult as they often have poor organoleptic properties attributed to the high water holding capacity, viscosity, and insolubility of components of the bran. Amaranth is a promising grain that is naturally gluten-free and has received much attention in recent years because of its excellent nutritional profile. Studies have shown encouraging approaches to modify the molecular makeup of amaranth by enzymatic hydrolysis. This approach suggests an increase in processability and incorporation of whole grain amaranth into processed foods by ameliorating the challenges inherent in the use of whole grain flours, thereby expanding consumer acceptance and intake of whole grains. This research investigates the effects of a two-level factorial design on the enzymatic hydrolysis of whole grain amaranth with enzymes alpha-amylase, cellulase, xylanase, and protease maintaining constant pH of 6 and temperature, 50°C. The main effects show decreased viscosity and water holding capacity, and increased solubility of whole grain amaranth. The most notable findings show enzymatic treatment decreases viscosity, with alpha-amylase having the most significant impact (P < 0.0001) 21,363-59± 244 cPs. Protease was eliminated from further testing as bitterness was generated with its hydrolysate. To solubilize insoluble components, a second two-level factorial design was employed analyzing pH (4.5 and 7.5) and temperature (50°C-70°C) with the same enzyme dosage as the first design. The main effects of the second design revealed alkaline conditions significantly increase soluble fiber (P < 0.0001) 3.01-5.05% ± 0.3%. Subsequent investigation proposes a response surface design with alpha-amylase in optimizing the effects of reaction time and alkaline conditions.

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