Dissertations / Theses: 'Grain storage'

1

Wagner, Christopher. "Comparative grain storage analysis." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/35752.

Full text

Abstract:

Master of Agribusiness
Department of Agricultural Economics
Brian C. Briggeman
Grain Elevators have towered the plains of Southwest Kansas for over the last half of a century. Many of these large white concrete structures were built during the 1950s using a slip form concrete design. While new grain storage has been built over time, many of the original slip form structures remain a large part of the farm cooperatives storage capacity. Grain production has continued to increase and put greater demand on storage facilities and handling capabilities. Thus, there is a need for cooperatives to meet the future demands of farmers by replacing or updating grain storage assets. The objective of this project is to provide a comparative analysis of grain storage options that a cooperative, primarily the Garden City Co-op, Inc. (GCC), could utilize in making a decision to update or replace grain storage assets. The project examines three different options for grain storage including concrete, steel, and bunker storage. The project will also examine extending the life of an original slip form elevator by installing a gunite bin liner. To determine which option that provides the most economic benefit to GCC and its members, Net Present Value and the Internal Rate of Return are estimated for each grain storage option. GCC historical grain handling margins and grain storage costs were derived from historical averages and bids from projects GCC has undertaken in the past five years, respectively. The model assumes receipts as a percentage of storage to accurately represent bushels handled by a facility. Grain storage is highly variable in initial cost and the operational needs will change in every circumstance. The results indicate that a large volume of grain is needed before economic profits will be realized.

APA, Harvard, Vancouver, ISO, and other styles

2

Di, Hua. "Understanding Chinese farmers' grain storage." Thesis, Montana State University, 1999. http://etd.lib.montana.edu/etd/1999/di/DiH1999.pdf.

Full text

Abstract:

China is the largest grain producer and consumer in the world. Since introducing its open-door policy in the 1980's, China has become an increasingly important grain importing country. However, China's wheat imports have varied considerably from year to year. One key issue affecting China's grain imports is its large on-farm grain reserves. This thesis is intended to examine factors significant for China's on-farm grain stocks and shed some additional light on its potential impacts on China's domestic grain markets and grain import activities. The key finding is that Chinese farmers' grain supply is primarily from self-production. The Chinese government decrees that farmers be not eligible to purchase grain from government food agencies that control 70 to 80 percent of the total marketed surplus of grain in China. This policy plus the underdeveloped domestic grain and credit markets leads Chinese farmers to store a considerable amount of grain for consumption. The food- and income-security concern of Chinese farmers is found to be another important factor in Chinese farmers' grain storage decisions. The highly variable weather, a still developing infrastructure, and frequent changes in government grain policies all increase the risk faced by Chinese farmers, thus increase their food- and income-security concerns. This thesis finds that the increasing number of farm family members working off-farm can help reduce the quantity of on-farm grain storage because of the potential remittance from more stable off-farm earnings to the farm home. It is also found that farmers tend to store less as income increases due to changes in absolute risk-aversions of farmers. The last important finding of thesis is that Chinese farmers' grain storage is somewhat price-elastic, in contrast with suggestions by some Chinese economists that China's on-farm grain storage is primarily for food-security concerns and therefore generally price-inelastic. It is also found that additions to farm household grain storage is directly elastic with respect to household grain output.

APA, Harvard, Vancouver, ISO, and other styles

3

Annis, Margaret Catherine, and n/a. "Extending stored grain research and technology to grain farmers." University of Canberra. Education, 1995. http://erl.canberra.edu.au./public/adt-AUC20060602.115607.

Full text

Abstract:

This thesis is concerned with an investigation into current on-farm grain storage practice and with ascertaining what educational interventions, if any, are appropriate for future and more detailed consideration. The Australian grain growing, handling, and marketing industry has changed in recent times. A few years ago (1989), the grain growers only essential contact with grain marketing was through the bulk handling authorities and the Australian Wheat Board. Advice was freely available from state departments of agriculture, and the only requirement to store grain on-farm was that necessary for the grower's own needs. Now (1994), there is a possible advantage that grain stored on-farm may be used for a wide range of selling options, amongst other reasons, and market requirements are much more complex and stringent. There is a substantial body of research on grain storage techniques. At the same time there is a significant gap between researched knowledge and the use of this knowledge for on-farm storage. A major purpose of this study is to identify an improved approach to extension and farmer education that may help to reduce this gap. This thesis contains a review of the general literature on extension followed by an overview of extension in the developed world to establish the international context for Australia. Then the historical context of extension is examined briefly to understand the current situation in each state. Some educational models are reviewed to identify relationships between stakeholders and the opportunities available for and constraints to development of educational strategies. Information channels are reviewed to comprehend extension interaction and grain storage technologies are reviewed to ensure comprehension of techniques. On the basis of the literature review a field study was designed to investigate current on-farm storage practice, current extension sources for storage information and preferences for future educational interventions. This was done by a survey using a stratified random sample of grain growers and cluster selection of individuals for personal interviews. This information was complemented by informal discussion with farmers at field days. The results of the study confirmed the gap between research knowledge and on-farm implementation of this knowledge. They also demonstrated that grain growers wanted more information and gave some indicators of how this might be achieved. Major findings of the research included the need for extension coalitions and the desirability for active involvement of the grain grower. Major conclusions, for on-farm storage and extension, are drawn to form a basis for development of future extension interventions. These are aimed at ensuring grain growers have available the information needed for good storage practice. This includes an essential understanding the grain growers' needs and perceptions, early, in any planning process. It also includes the necessity for coordination of extension/education activities at local, regional and national levels. The research has some major implications for an improved approach to extension and on-farm storage. These include the establishment of a farmers-as-researcher program to implement grain storage innovations and the recognition that implemented change will need long term maintenance; often more resource intensive than the original intervention.

APA, Harvard, Vancouver, ISO, and other styles

4

Caffarelli, Peter Anthony. "A Descriptive Study of Grain Production, Consumption, and Storage in Virginia." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/64485.

Full text

Abstract:

Agriculture is an important industry in Virginia, with an array of crops grown and animals produced. Virginia's crop, livestock, and poultry sectors sold agricultural products worth $1.4 billion and $2.4 billion, respectively, in 2012. One of the products, grain, serves as an important input for raising livestock and poultry. Virginia needs to import grain from other states (Eastern Corn Belt states) to meet current livestock feed requirements, an expense that raises the cost of production over locally sourced grains . Further, such movements of grain from producing-areas to demand-areas rely on the efficient and timely interaction of grain storage and transportation. Describing the details of the grain supply chain provides insights into the interplay and relationships among production, storage, transportation, and end users of grains and oilseeds in Virginia. Results of a state-wide survey of Virginia grain producers shed light on the following topics: current cropping practices; current grain storage practices; available farm-level storage and its use, age, and expected life; and future storage plans and constraints. Overall findings include, grain production in Virginia has generally increased over the last decade, yet storage capacity remains constant and continues to age; livestock and poultry populations are declining leading to less demand for feed grains and oilseeds; grain farmers report satisfaction with their current storage situation and higher returns to stored grain may encourage "non-storers" to build storage; and the majority the grain leaving the farm is hauled by truck over short distances (25 miles or less). Overall, the results provide a foundation for understanding the grain supply chain in Virginia and offer useful information to Virginia's agricultural stakeholders.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

5

Dejene, Mashilla. "Grain storage methods and their effects on Sorghum grain quality in Hararghe, Ethiopia /." Uppsala : Dept. of Ecology and Crop Production Science, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a454.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Cook, Samuel A. L. "Evaluation of sealed storage silos for grain fumigation." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32895.

Full text

Abstract:

Master of Science
Department of Grain Science and Industry
Dirk E. Maier
Fumigation of stored grain is a common way to kill stored-grain insect pests. However, fumigating in unsealed structures is the leading cause of control failures and subsequent development of insect resistance. Sealing the storage structure is the only practical way to ensure a complete kill of all insects at all life stages. The cost, effort, and feasibility of sealing a U.S. corrugated steel silo during construction was evaluated and compared against an Australian sealed silo designed for fumigation. Gas monitoring and thermosiphon recirculation equipment was installed on both silos. Fumigation efficacy was evaluated using pressure half-life decay times, fumigant concentrations, insect bioassays, and grain quality data. Three fumigations with phosphine (PH₃) pellets or tablets and two with VAPORPH₃OS® cylinderized PH₃ and ProFume® cylinderized sulfuryl fluoride (SF) were performed in each silo for a total of ten experimental treatments. The Australian silo required 266 man-hours to construct and cost $180 for additional sealing, compared to 359 man-hours and $3,284 for constructing and sealing the U.S. silo. The Australian silo had a maximum pressure half-life decay time of 163 s versus 50 s for the U.S. silo. At application rates of 1.5 g/mᶟ of PH₃ both silos maintained an average concentration of approximately 0.28 g/mᶟ for 14 days. With thermosiphon recirculation the average minimum-to-maximum PH₃ concentration ratio in the U.S. silo was 0.52, compared to a ratio of 0.17 when fumigating without thermosiphon recirculation. Greater than 99% adult mortality was observed in all insect bioassays which included PH₃ resistant strains of R. dominica and T. castaneum. The average emergence from fumigated bioassays was 7 adult insects, compared to an average of 383 adults for the non-fumigated controls. Grain stored for 10 months in the sealed silos increased from approximately 11.5% to 17% m.c. in the top 0.3 m of grain, and decreased in test weight from approximately 77 to 65 kg/hL. Although the Australian silo retained higher fumigant concentrations than the U.S. silo, fumigations were successful in both. Long-term storage in sealed silos is a concern because grain quality can deteriorate due to condensation and mold in the top grain layer.

APA, Harvard, Vancouver, ISO, and other styles

7

Rop, Jayne. "Cost implications of alternative grain storage programs : the case of Kenya." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22798.

Full text

Abstract:

The main objective of this study was to estimate the costs associated with different storage levels of maize for the National Cereals and Produce Board (the NCPB), the grain marketing agency of the Kenyan government.
Four storage level scenarios were considered. The first involved a zero-supply security scenario, where the model was required to simply satisfy the demand in each period. The second, third and fourth respectively, involved two, three and four months supply security scenarios, where the model was required to purchase grain equivalent to the demand for those periods. Scenario two, providing two months supply security was not discussed because it posted results similar to scenario one. The hypothesis that a stocks management model can be developed to be used by the NCPB in order to determine the optimal quantities of maize that it handles every year, while minimizing costs, was partly supported under scenarios one and three. However, despite the reduction in costs under scenario one, the lack of inventory and foreign trade was seen to increase the risks and uncertainties associated with variations in production, especially under cases of short supply. Similarly, the lack of foreign trade under scenario three was postulated to increase risks and uncertainties in periods of low production. Under scenario four, the results involved foreign trade, and inventory was positive for most years. However, these results were suboptimal and thus unreliable for policy decisions. Nevertheless, results under this scenario were very similar to the actual performance of NCPB for the period 1980 to 1990.
The results of this study show that external trade may not be the solution to a strategy of cost minimization. It was concluded, therefore, that the present strategy of self-sufficiency may be the better alternative. (Abstract shortened by UMI.)

APA, Harvard, Vancouver, ISO, and other styles

8

Milstead, Andrew. "Corn storage and marketing feasibility in northern Mississippi." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35327.

Full text

Abstract:

Master of Agribusiness
Department of Agricultural Economics
Daniel M. O'Brien
On-farm grain storage plays a key role in the production and distribution of corn in the United States. It can have economic impacts on a farm’s profitability and production efficiency over time. With the free market system of the United States, market fundamentals are a key component of decisions made on the farm regarding construction of grain storage facilities and how they are used in marketing decisions throughout a given production and marketing year. This analysis researches how grain storage decisions in the Northern Mississippi area are effected by corn basis differentials between the Memphis, TN river market and the Northern Alabama corn market. Corn basis differentials are considered along with annual changes in corn futures market carry in response to variations in grain market fundamentals. The profitability of constructing, maintaining, and operating on-farm grain storage is analyzed based on the local history of the local corn market basis patterns and the carry priced into the corn futures market. Through this analysis it was found that the biggest obstacle affecting the profitability of on-farm grain storage was the upfront cost of the facility. As costs of the facility were incurred, grain had to be stored for longer periods of time in order to be profitable based on history of improved basis and market carry over time. On-farm storage became profitable over a shorter storage period once the upfront costs of grain storage and handling facilities were paid based on the operating costs and market conditions within the analysis. On-farm storage can be a useful tool for a farm to increase profitability over time, beyond the scope of this analysis. This analysis proves that in the Northern Mississippi area over time, grain storage can be profitable based on improved cash basis and futures market carry. However, due to ever-changing market conditions, on-farm grain storage does not replace the need for the development of grain marketing plans in order to increase the likelihood of profitability.

APA, Harvard, Vancouver, ISO, and other styles

9

Milindi, Paschal. "Improved Hermetic Grain Storage System for Smallholder Farmers in Tanzania." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469166460.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Silva, Luís César da. "Stochastic simulation of the dynamic behavior of grain storage facilities." Universidade Federal de Viçosa, 2002. http://www.locus.ufv.br/handle/123456789/9468.

Full text

Abstract:

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-02-09T15:05:24Z No. of bitstreams: 1 texto completo.pdf: 1153041 bytes, checksum: 3894e22f554e535b931c746ac5e7b4df (MD5)
Made available in DSpace on 2017-02-09T15:05:24Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1153041 bytes, checksum: 3894e22f554e535b931c746ac5e7b4df (MD5) Previous issue date: 2002-05-21
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Unidades armazenadoras de grãos podem ser definidas como sistemas projetados e estruturados para receber, limpar, secar, armazenar e expedir grãos e oleaginosas. Para alcançar essas metas apropriadamente, estruturas, máquinas de processamento e transportadores são interligados, segundo um fluxograma lógico, e tomadas decisões operacionais. Devido à dinâmica do sistema da unidade armazenadora de grãos e a influências de fatores aleatórios externos, como o processo de colheita e a demanda do mercado, não são recomendados o emprego de métodos estáticos em estudos de avaliações e análises para este tipo de sistema. Isso se deve ao fato de que os métodos estáticos podem levar os tomadores de decisões a cometer erros, como também colocá-los em situações embaraçosas ao procurar estabelecer correlações entre as variáveis envolvidas. Por essa razão, a simulação se apresenta como a técnica mais adequada, por permitir um melhor entendimento dos parâmetros selecionados para a tomada de decisão, além de propiciar a condução de experimentos, como: análise de sensibilidade, análise de cenários, otimização e simulação de Monte Carlo. Dessa forma, visando permitir engenheiros, projetistas, gerentes e demais tomadores de decisões simularem a dinâmica operacional, conduzirem experimentações e realizarem análises de viabilidade, considerando-se unidades armazenadoras existentes e novas, foi desenvolvida uma ferramenta para estruturação de modelos de simulação. Essa ferramenta, denominada Grain Facility, foi desenvolvida utilizando-se o software Extend TM , versão 4.1.3C. Grain Facility é classificada como uma biblioteca do Extend TM , que contém um conjunto de blocos que propiciam: (i) introduzir dados que governam o sistema, (ii) simular as operações unitárias associadas ao ambiente das unidades armazenadoras de grãos, (iii) coletar e apresentar informações durante a simulação e (iv) gerar relatórios e gráficos. Para o desenvolvimento da biblioteca Grain Facility, dos modelos e dos estudos de verificação e validação, dados foram obtidos na Cooperativa Agropecuária Mourãoense Ltda. – COAMO, com sede em Campo Mourão, Paraná, Brasil. Os dados referem-se a: (i) consumo mensal de energia elétrica, (ii) consumo anual de lenha utilizada no processo de secagem, (iii) quantidades diárias de produtos recebidas, (iii) quantidades mensais de produtos expedidas, (iv) fluxogramas das unidades armazenadoras visitadas e (v) informações técnicas sobre equipamentos e estruturas. Com base nos resultados, pode-se concluir que Grain Facility possui significativo potencial para solução de problemas, uma vez que essa ferramenta permite a estruturação de modelos que são úteis em aplicações como: (i) análises de viabilidade, (ii) entendimento dos casos em estudo, (iii) estimativa do consumo de energia elétrica e combustível no processo de secagem e (iv) avaliação de sistemas novos e existentes, bem como das necessidades de expansão, remodelação e inovação tecnológica.
A grain storage facility may be defined as a designed and structured system for receiving, cleaning, drying, storing, and dispatching grains and legumes. To perform these tasks appropriately, structures, processing machines, and conveyors are logically linked and management decisions are made. Due to the dynamic of grain storage facilities and external random factors, such as the harvest process and market demand, evaluation and analysis using static techniques are not recommended. Static methodologies may lead decision makers to erroneous conclusions or put them in an awkward position when trying to correlate the several variables involved. For these reasons, simulation proves to be a more than adequate method to better understand the studied decision parameters; and it is ideal for conducting sensitivity analysis, scenario analysis, optimization, and Monte Carlo simulation. Thus, a simulation toolset was developed to allow engineers, designers, managers, and other decision makers to model the dynamic behavior of new and existing grain storage facility and conduct related experiments and feasibility analyses. This toolset, called “Grain Facility,” was developed by using Extend TM software, version 4.1.3C. “Grain Facility” is an Extend TM library holding a set of blocks that enable the user to: (i) input information which rules system operations, (ii) simulate unit operations related to the grain storage facility environment, (iii) collect and display information during the simulation process, and (iv) generate reports and graphics. For the development of models using the “Grain Facility” library and for the following study’s verification and validation sections, data were obtained from the Cooperativa Agropecuária Mourãoense Ltda. (COAMO), an agricultural cooperative headquartered in Campo Mourão, Paraná State, Brazil. The data refer to: (i) monthly electric energy consumption, (ii) annual consumption of firewood used in the grain drying process, (iii) daily quantity of product received, (iv) monthly quantity of product dispatched, (v) a flowchart of the grain storage facilities visited, and (vi) technical information about processing machines, conveyors, and structures. This study’s outcomes show that Grain Facility has significant problem solving potential. It allows the structuring of models that have various applications, such as (i) conducting grain storage facility feasibility analyses, (ii) estimating electric energy and fuel consumption at grain storage facilities, (iii) acting as teaching tools to make cases under study more readily understandable, and (iv) analyzing new and existing systems to make them more efficient or to provide direction for facility remodeling and technological updating.
Tese importada do Alexandria

APA, Harvard, Vancouver, ISO, and other styles

11

Reuss, Rainer, and n/a. "The loss of grain freshness : indicators or storage induced quality loss in dry barley and canola grain." University of Canberra. Applied Science, 1999. http://erl.canberra.edu.au./public/adt-AUC20061107.123442.

Full text

Abstract:

The work presented here explores the effect of storage on chemical and other characteristics of dry, free of added chemicals and pest-free barley and canola grain. This was achieved by measuring the changes in a number of variables of grain stored at different temperatures under laboratory conditions and in commercial storage. The following measurements were carried out: Viability, moisture contents (mc), oil contents (oc), whole grain colour, spectrophotometry of grain extracts, hydroxy methyl furaldehyde (HMF), changes in storage atmospheres, organic sulphide levels, tocol concentrations (vitamin E), Iodine Value (IV), Thiocyanogen Value (TV), Peroxide Value (PV), p-Anisidine Value (p-AV) and Acid Value (AV). The mc of canola and barley were within the range considered safe for storage. Oil content of canola did not change significantly with storage. Viability of canola stored at 4 and 25 °C did not change noticeably, but higher storage temperatures resulted in seed death. Barley maintained high viabilities at low temperatures, but was more susceptible to high temperatures than canola. Colour changes of whole barley grain in storage were pronounced and temperature dependent. Colorimetry of whole barley grain showed potential as a tool for monitoring quality changes in storage. Absorption spectra of grain extracts reflected chemical and physiological changes in storage. HMF, an indicator of Maillard browning, accumulated in short to medium term storage at 45°C and in long term storage at 25 and 35°C. Measurement of HMF was considered useful for monitoring quality changes of stored cereal grain. In a study of storage atmospheres, changes in the concentrations of carbon dioxide, carbon monoxide, oxygen, carbon disulphide and carbonyl sulphide were shown to be useful indicators of quality loss of grain in storage. Gas concentrations usually depended on storage temperature and time and reflected the storage history of the commodity. They indicated loss of carbohydrates and lipids by respiration, oxidative damage and deterioration of sulphur containing amino acids and other compounds. Oil quality indicators were consistent with oxidative damage to canola lipids in storage. IV, TV, and p-AV of canola oil did not correlate with quality of commercial samples. However, a relationship between increases in PV and high storage temperatures in canola was shown and AV increased in storage dependent on storage temperature and time. In barley and canola, the concentration of anti-oxidant tocol species (vitamin E) decreased at 35 and 45°C storage dependent on storage time. The overall tocol content as well as vitamin E activity decreased with storage decreasing the nutritional value of the commodities and indicating oxidative damage to lipids. It was concluded that the storage of dry, pest-free whole barley and canola grain at moderate temperatures (25-45°C) resulted in chemical and other changes. The consequence of these changes was a measurable reduction in the freshness of grain relevant to the nutritional, food technological and commercial quality of grain.

APA, Harvard, Vancouver, ISO, and other styles

12

Petersson, Stina. "Yeast/mold interactions during airtight storage of high-moisture feed grain /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1998. http://epsilon.slu.se/avh/1998/91-576-5505-7.gif.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Garrett, David L. "Wheat-Gold Currency How To Make Large-Scale Grain Storage Possible." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1169.

Full text

Abstract:

The United States has a National Oil Reserve but no food reserve. Just as the oil reserve is designed to buffer unforeseen disruptions in the critical supply, the nation should also have a food reserve for at least the same purpose. The United States and other developed nations have little or no food reserve beyond the typical demands between growing seasons. Marvelous production achievements in agriculture beginning in the early 1960s and known as the “Green Revolution” are now leveling off. Food production, suffering from such negative side effects as reduced water tables, is being outstripped by population growth (Bourne, 2009). In 2006 through 2008 the US and world drawdown of wheat and other grain stocks, together with agricultural events such as droughts in various parts of the world, caused grain reserves to hit historically low levels. The resulting lack of supply created significant disruptions, including record high prices (Figure 1) (Good and Li, 2010, USDA - Foreign Agricultural Service, 2011), countries refusing to export, riots, and famine (CNN.com, 2008). The need for higher world grain stocks seems clear. Higher grain stocks should result in lower price volatility and higher food security in Utah, the US, the UK, and internationally.

APA, Harvard, Vancouver, ISO, and other styles

14

Ameobi, John Babatope. "Maize drying with ambient air." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386835.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Nang'ayo, Francis L. O. "Ecological studies on larger grain borer in savanna woodlands of Kenya." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369505.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Gan, G. "Heat and moisture transfer in deep bed cooling of grain and vegetables." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234390.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Van, der Merwe Mathys Johannes Nicolaas. "Determinants of the supply-side fragmentation of maize storage in the North Western Free State production area / Mathys Johannes Nicolaas van der Merwe." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9228.

Full text

Abstract:

For decades commercial silos in South Africa was the only option in which maize could be delivered and sold. After deregulation in the late 1990s commercial silo owners came to face the challenge of alternative storage solutions and loss of market share. The reasons are determined for a shift from commercial storage to on-farm storage. The extent to which on-farm storage will change the current maize storage industry is discussed. The study commences by describing the birth and rapid growth of maize production in South Africa. Soon after maize became a major role-player in the export industry, it was characterised by regulation. The rationale why the market was regulated and how it influenced grain storage is explained. The deregulation process and the objectives of the new Marketing of Agricultural Products Act, No. 47 of 1996, are paraphrased. In the deregulated market, current and future, maize prices are determined by supply and demand. Incentives for storage emerged and cheaper substitutes with various other advantages began to propose alternative storage solutions to farmers. These concurrences of circumstances then lead to fragmentation of grain storage in South Africa. As a relatively young free market, the maize value chain is described to illustrate the position of each role-player in relation to the silo owner. The new price determination factors, price movement rationale and the use of market instruments are subsequently explained. Naturally, a critical assessment of the main different storage solutions available for farmers, are investigated next. Fragmentation is defined and discussed in terms of market equilibrium. A comparison is drawn between the South African and the Australian as well as the US maize storage industry. The empirical research was conducted on two sample groups of farmers in the Free State. The first group is farmers that already make use of an on-farm storage facility. The second group is farmers that annually produce more than 5000 tons of maize and currently do not make use of an on-farm storage facility. Seven important reasons for an on-farm storage facility are determined in the literature study as well as a qualitative study that preceded the quantitative study. Respondents are asked to rank the reasons in order of, in their opinion, importance. A generalized profile of a respondent in each sample group was compiled. Hereafter the outcome of the reasons ranked by both sample groups is discussed. It appeared that Flexible Marketing Option was the most important reason for farmers that already make use of on-farm storage. Farmers did not indicate that Handling and Storage costs are the most important reason why they would invest in an on-farm storage facility. Correlations are drawn between groups and the significance of differences is determined. It is concluded that on-farm storage is sustainable and there will be an increase of the phenomenon over the next three years. Recommendations are given for commercial silo owners to regain market share. Costs analyses and effective cost management along with the promotion that marketing options are just as flexible within commercial silos, as it is outside, are some of the recommendations made.
Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

APA, Harvard, Vancouver, ISO, and other styles

18

Sing, Sharlene E. "Suppression of bruchids infesting stored grain legumes with the predatory bug Xylocoris flavipes (Reuter) (hemiptera: anthocoridae)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29789.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Geng, Yang GENG. "Understanding Current On-Farm Storage Systems and Safety Practices of Ohio Cash Grain Operators." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461298325.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Turner, Aaron P. "DEVELOPMENT OF A DECISION SUPPORT SYSTEM FOR CAPACITY PLANNING FROM GRAIN HARVEST TO STORAGE." UKnowledge, 2018. https://uknowledge.uky.edu/bae_etds/58.

Full text

Abstract:

This dissertation investigated issues surrounding grain harvest and transportation logistics. A discrete event simulation model of grain transportation from the field to an on-farm storage facility was developed to evaluate how truck and driver resource constraints impact material flow efficiency, resource utilization, and system throughput. Harvest rate and in-field transportation were represented as a stochastic entity generation process, and service times associated with various material handling steps were represented by a combination of deterministic times and statistical distributions. The model was applied to data collected for three distinct harvest scenarios (18 total days). The observed number of deliveries was within ± 2 standard deviations of the simulation mean for 15 of the 18 input conditions examined, and on a daily basis, the median error between the simulated and observed deliveries was -4.1%. The model was expanded to simulate the whole harvest season and include temporary wet storage capacity and grain drying. Moisture content changes due to field dry down was modeled using weather data and grain equilibrium moisture content relationships and resulted in an RMSE of 0.73 pts. Dryer capacity and performance were accounted for by adjusting the specified dryer performance to the observed level of moisture removal and drying temperature. Dryer capacity was generally underpredicted, and large variations were found in the observed data. The expanded model matched the observed cumulative mass of grain delivered well and estimated the harvest would take one partial day longer than was observed. Usefulness of the model to evaluate both costs and system performance was demonstrated by conducting a sensitivity analysis and examining system changes for a hypothetical operation. A dry year and a slow drying crop had the largest impact on the system’s operating and drying costs (12.7% decrease and 10.8% increase, respectively). The impact of reducing the drying temperature to maintain quality in drying white corn had no impact on the combined drying and operating cost, but harvest took six days longer. The reduced drying capacity at lower temperatures resulted in more field drying which counteracted the reduced drying efficiency and increased field time. The sensitivity analysis demonstrated varied benefits of increased drying and transportation capacity based on how often these systems created a bottleneck in the operation. For some combinations of longer transportation times and higher harvest rates, increasing hauling and drying capacity could shorten the harvest window by a week or more at an increase in costs of less than $12 ha-1. An additional field study was conducted to examine corn harvest losses in Kentucky. Total losses for cooperator combines were found to be between 0.8%-2.4% of total yield (86 to 222 kg ha-1). On average, the combine head accounted for 66% of the measured losses, and the total losses were highly variable, with coefficients of variation ranging from 21.7% to 77.2%. Yield and harvest losses were monitored in a single field as the grain dried from 33.9% to 14.6%. There was no significant difference in the potential yield at any moisture level, and the observed yield and losses displayed little variation for moisture levels from 33.9% to 19.8%, with total losses less than 1% (82 to 130 kg dry matter ha-1). Large amounts of lodging occurred while the grain dried from 19.8% to 14.6%, which resulted in an 18.9% reduction in yield, and harvest losses in excess of 9%. Allowing the grain to field dry generally improved test weight and reduced mechanical damage, however, there was a trend of increased mold and other damage in prolonged field drying.

APA, Harvard, Vancouver, ISO, and other styles

21

Ward, Lacey L. "Profitability of storage hedges for Kansas wheat producers." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19054.

Full text

Abstract:

Master of Science
Agricultural Economics
John A. Fox
Hard Red Winter Wheat is an extremely important part of the Kansas agricultural industry. In Kansas, this type of wheat is planted in the fall and harvested in mid-June. After harvest, producers have the option to either store or sell their wheat. If they decide to store, the wheat can be stored on-farm or in a commercial facility. Another storage decision is whether to store the wheat hedged or unhedged (speculative) storage. Hedging is a technique to limit the price risk associated with selling or buying commodities. This study compared hedged and speculative decisions for both on-farm and commercial storage scenarios for 108 locations geographically dispersed across Kansas. Wednesday prices were gathered for each location during the 10-year time period from 2004 to 2013. All monthly storage period possibilities from July to May were examined to determine the storage returns potential. All results are displayed as the profit or loss achieved compared to selling in June at harvest. Averages for Kansas were negative or slightly positive for all storage scenarios, but hedged returns showed much less variability in results compared to speculative returns. Regional differences showed that North Central Kansas displayed the highest level of basis improvement over the 10-year period followed by South Central Kansas. A regression analysis using nearby basis in June, harvest price, and futures contract spreads as independent variables and storage returns as a dependent variable showed emphasis on the futures spread having the biggest influence on storage profits.

APA, Harvard, Vancouver, ISO, and other styles

22

Morales, Quiros Alejandro. "Evaluation of ambient and chilled aeration strategies to maintain the quality of stored grain in tropical climates and during summer in temperate climates." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/38261.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

23

Ädel, Druvefors Ulrika. "Yeast biocontrol of grain spoilage moulds : mode of action of Pichia anomala /." Uppsala : Dept. of Microbiology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a466.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Mat, Isa Zaiton. "Mathematical modelling of fumigant transport in stored grain." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/75420/1/Zaiton_Mat%20Isa_Thesis.pdf.

Full text

Abstract:

Computational fluid dynamics, analytical solutions, and mathematical modelling approaches are used to gain insights into the distribution of fumigant gas within farm-scale, grain storage silos. Both fan-forced and tablet fumigation are considered in this work, which develops new models for use by researchers, primary producers and silo manufacturers to assist in the eradication grain storage pests.

APA, Harvard, Vancouver, ISO, and other styles

25

Guntrip, John. "Variation and covariation in and between life-history traits of the larger grain borer, Prostephanus truncatus (Coleoptera, Bostrichidae), : and the cowpea weevil, Callosobruchus maculatus (Coleoptera, Bruchidae), with particular reference to trade-offs." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259509.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Popelka, Paul. "Net present value analysis of an automated grain aeration system technology on stored corn." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19034.

Full text

Abstract:

Master of Agribusiness
Agricultural Economics
Allen M. Featherstone
The purpose of this thesis is to analyze whether the use of automated aeration systems for reducing moisture in corn during storage provides sufficient net present value for Nebraska corn farmers. The objective is to examine if an automated aeration system provides sufficient energy savings, marketing opportunities and reduced drying costs before corn delivery to an elevator. On-the-farm corn storage has steadily increased and harvesting corn before the moisture has achieved the desired targets cost farmers in drying charges and shrink. Farmers are interested in whether automated aeration systems can remove enough moisture from grain, without over-drying the bin, without spending a large amount of time determining when to run their grain bin aeration fans. Data for this project were obtained from four privately owned 60,000 bushel grain bins outfitted with the IntelliAir™ BinManager™ automated aeration system. Moisture samples were taken from each of the trucks hauling grain to the bin and again after removal of the corn after the automated system had ran for 9 months. Energy usage, drying charges, and shrink were calculated for the initial corn moisture averages and the moisture at the time of removal. Each bin was examined using Net Present Value (NPV) analysis to determine whether the energy savings were enough to offset the initial installation cost and annual expenses of the project. After the NPV was estimated for each of the bins, a sensitivity analysis of how corn price changes and no aeration required would affect the NPV analysis. Finally, an analysis of the total costs savings of a continuously ran aeration system was compared to the automated aeration system. The conclusion of the NPV analysis was that adding an automated aeration system would be profitable under most scenarios. More studies are needed to determine the profitability of automated aeration systems in different regions, moisture inputs, and bin sizes.

APA, Harvard, Vancouver, ISO, and other styles

27

Hasanoglu, Mehmet Sinan. "Storage Reliability Analysis Of Solid Rocket Propellants." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12609897/index.pdf.

Full text

Abstract:

Solid propellant rocket motor is the primary propulsion technology used for short and medium range missiles. It is also commonly used as boost motor in many di_erent applications. Its wide spread usage gives rise to diversity of environments in which it is handled and stored. Ability to predict the storage life of solid propellants plays an important role in the design and selection of correct protective environments. In this study a methodology for the prediction of solid propellant storage life using cumulative damage concepts is introduced. Finite element mesh of the solid propellant grain is created with the developed parametric grain geometry generator. Finite element analyses are carried out to obtain the temperature and stress response of the propellant to the environmental thermal loads. Daily thermal cycles are assumed to be sinusoidal cycles represented by their means and amplitudes. With the cumulative damage analyses, daily damage accumulated in the critical locations of the solid propellant grain are investigated. Meta-models relating the daily damage amount with the daily temperature cycles are constructed in order to compute probability of failure. The results obtained in this study imply that it is possible to make numerical predictions for the storage life of solid propellants even in the early design phases. The methodology presented in this study provides a basis for storage life predictions.

APA, Harvard, Vancouver, ISO, and other styles

28

Vaze, Prabhat Bhaskar. "A model of inter-regional trade and storage of grain : an application to Zimbabwe and Tanzania." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/22709.

Full text

Abstract:

This thesis looks at the economics of staples trade in the sub-Saharan region, verifying an economic model using data from the white maize markets of Zimbabwe and Tanzania. Both countries have reformed their grain marketing system in the recent past. In the early 1980s, the government was the main actor in the food distribution system, operating through large state-owned marketing boards. However, under pressure from international agencies, first Tanzania and then Zimbabwe, liberalised their food markets and the role of the private sector increased. The state has remained a player in the market and a mix between public and private marketing system has evolved. White maize is the main staple of both the countries and there is only one harvest, around April. The peculiar agroecology of the crop means that inter-regional trade has to be combined with storage to meet consumer needs. The economics of this food system is analysed using an optimal control framework. In a model of inter-regional trade where there is a single harvest at the start of the period and an external market which fixes a low buying and a high selling price, it is shown that trade is intermittent. In particular, regions would first source consumption from own stocks, then trade and finally purchase grain from the external market until the following years harvest. The model is first investigated using household survey data collected in 1994-95 from 356 households in Buhera Communal Area, Zimbabwe. The harvest was poor and private traders had, for the first time since liberalisation, established direct trade links between food deficit parts of Buhera and surplus neighbouring areas. Also, the analysis gives the first indication of the role of the state marketing agency, post-reform.

APA, Harvard, Vancouver, ISO, and other styles

29

Fakude, Moelo Patience. "Eradication of storage insect pests in maize using microwave energy and the effects of the latter on grain quality." Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-01292009-131525.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Abomhara, Aisha. "Analysis of the cuticle of two species of grain storage pest and interaction with germination of entomopathogenic fungi." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/96212/4/Aisha_Abomhara_Thesis.pdf.

Full text

Abstract:

This thesis compares the early stages in germination and infection of two entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana on the cuticle of two important pest of grain, the beetles Tribolium castaneum and Rhyzopertha dominica using scanning electronic microscopy. It is the first study to report the chemical composition of wing and elytra from these two grain beetles using gas chromatography mass spectrometry. The thesis discusses the potential impact of the components of the cuticle on the observed patterns of germination and growth of the entomopathogenic fungi.

APA, Harvard, Vancouver, ISO, and other styles

31

Johnson, Brent S. "Benefits of flour storage as related to process efficiencies in milling." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/15057.

Full text

Abstract:

Master of Agribusiness
Department of Agricultural Economics
Bryan Schurle
The milling of wheat into white flour is a high volume, low margin business. Flour is a commodity. Competition is fierce. Over the past several years, there have been several mergers and acquisitions leading to fewer, but larger flour mills. The number of companies in the flour milling business has diminished as well. Flour sold in small packages on the grocery store shelf is but a small part of the business these days. Most flour is sold to commercial bakers in large bags or bulk trucks. The process of milling wheat into white flour consists of numerous variables within an extensive collection of equipment. It is the job of the miller to minimize the negative impact of these variables or at least hold constant as many of these variables as possible while achieving the best efficiency possible. To lessen the effect of these numerous variables on a large extensive system makes for a well running operation. When efficiency is achieved, a flour milling operation can be a profitable venture. A number of the variables that influence efficiency are affected by the amount of flour storage that a flour mill has. This thesis examines the benefits of flour storage as related to flour process efficiencies in milling. With flour mills operating at large output capacities, it is necessary for a flour mill to have adequate bulk flour storage bins as well as the right amount of warehouse space. Changes from one type flour to another in a flour mill require some time and an abundance of intervention by a skilled operator or miller. Having the proper amount of storage space makes it possible to minimize changes as well as the opportunity to optimize production of each specific flour type that is processed on the mill. To justify capital project money to invest in the proper amount of storage can be a challenge. Warehouse space and bulk flour storage can be expensive, and it is difficult to quantify how theoretical improvements will increase production and quality in the end product of flour. Using regression methods, production data obtained from an average sized commercial flour mill was used to estimate the increase in extraction due to a longer length of run allowed by the addition of storage space. By increasing the time a mill stays on a specific wheat mix to a minimum of twenty hours, there is a theoretical increase in extraction of 1.02 percentage points, resulting in wheat savings of over $500,000 per year. This resulting savings on the raw input material showed that capital expenditures on storage can be justified. A positive net present value and good internal rate of return show that the increased efficiency due to longer lengths of run justified the additional expense of the additional storage capacity. As volatility and the price per bushel of grain continue to increase, having the proper plant infrastructure with regard to storage space is of the utmost importance. Other benefits of storage will be realized as well in the area of flour quality and customer service.

APA, Harvard, Vancouver, ISO, and other styles

32

Nascimento, Vânia Rosal Guimarães 1983. "Desempenho de diferentes estrategias de aeração de milho armazenado." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256935.

Full text

Abstract:

Orientador: Marlene Rita de Queiroz
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
Made available in DSpace on 2018-08-15T16:57:39Z (GMT). No. of bitstreams: 1 Nascimento_VaniaRosalGuimaraes_M.pdf: 3937712 bytes, checksum: 22617dfc4dd3e6254ab76e50ba704be8 (MD5) Previous issue date: 2010
Resumo: A eficiência do processo de armazenagem de grãos não consiste apenas em "guardar" a produção agrícola, mas, sobretudo evitar a ocorrência de migração de umidade, incidência de insetos e desenvolvimento de microrganismos nos grãos durante esse processo. A técnica de aeração é atualmente empregada na redução e homogeneização da temperatura intergranular com o objetivo de minimizar esses problemas. Essa prática consiste na passagem forçada de ar ambiente através da massa de grãos. Assim, o objetivo desta pesquisa consistiu em avaliar e comparar o desempenho de três diferentes estratégias de aeração de grãos de milho, armazenados por vinte e quatro dias. As estratégias pesquisadas foram as seguintes: um sistema funcionando continuamente; outro sistema acionado durante o período da noite e um terceiro sistema que operou somente quando a umidade relativa do ar ambiente estava em equilíbrio com a umidade do ar interno aos grãos. Foram utilizados grãos de milho com dois níveis de umidade distintos, 13 e 18%. Realizou-se monitoramento contínuo da temperatura por meio de sensores instalados dentro dos silos e amostras de grãos foram retiradas durante os ensaios para determinação do teor de umidade, contagem de fungos e condutividade elétrica. Ao final dos ensaios, observou-se que todas as estratégias de aeração empregadas favoreceram redução de temperatura, em grãos secos (13%) e umidificados (18%). Porém, nenhuma estratégia manteve a temperatura no interior dos grãos homogênea durante o período de armazenamento. Ressalta-se, no entanto, que o sistema de aeração contínuo aplicado aos grãos de milho úmidos proporcionou menor heterogeneidade da temperatura ao longo da altura da massa de grãos, além de evitar o desenvolvimento de fungos. O teor de umidade dos grãos sofreu variações durante o período experimental, com tendência de secagem dos grãos ao final do processo. Verificou-se grande ocorrência de fungos nos grãos advindos do campo, principalmente Fusarium e Penicillium. A condutividade elétrica dos grãos de milho apresentou-se constante durante o período de armazenamento. A operação de aeração promoveu resfriamento dos grãos, entretanto em níveis elevados de temperatura e propícios para a incidência de insetos. Dessa forma, a aeração deve fazer parte do manejo integrado de pragas, mas não a única ferramenta
Abstract: The efficiency of grain storage doesn't consist only to "save" the agricultural production, but mainly to avoid the problem with the moisture migration, incidence of insects and development of microorganism in grains, during the process. Aeration is currently used for reducing and homogenization the intergranular temperature, aiming to minimize these problems. This practice consists of blowing ambient air through the grain mass. The objective of this research was to evaluate and compare the performance of three different strategies for aeration of corn grains, stored for twenty-four days. The strategies were: (1) a continuously system; (2) an aeration system activated only during the night and (3) an aeration system operating only when the relative humidity environment corresponds to the grains equilibrium moisture content. Corn grains at two different moisture content levels, 13 and 18% were used. Continuous monitoring of temperature was carried out through 12 sensors installed inside the bins. Grain samples were taken during the experiments for determination of moisture content, mold counts and electrical conductivity. At the end of the tests, all aeration strategies showed temperature reduction in to the bins with dried grain dry grains (11%) and wet grain (16,8%). However, any strategy maintained the homogeneous temperature inside the grain during the storage period. It is emphasized, however, that the continuous aeration system applied to the wet corn grain allowed low heterogeneity in the temperature along of the height of grain mass, and avoided the growth of mold. Grain moisture content changed during the experimental time with tendency of drying at the end of the process. There was a high occurrence of field mold in the grains, mainly Fusarium and Penicillium. Electrical conductivity of corn grains remained constant along the storage time. Aeration promoted cooling of the grains, however the temperature levels were high and appropriate conducive to the incidence of insects. Therefore, aeration should be a part of integrated pest management, but not the only tool
Mestrado
Tecnologia Pós-Colheita
Mestre em Engenharia Agrícola

APA, Harvard, Vancouver, ISO, and other styles

33

Delon, Rémi. "Incorporation et diffusion de l’hélium et de l’argon dans l’olivine polycristalline." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0207/document.

Full text

Abstract:

Les gaz rares sont d’excellents traceurs des hétérogénéités géochimiques et isotopiques présentes dans le manteau terrestre. Cependant, le stockage et le transport de ces éléments dans les minéraux mantelliques restent mal compris. Cette thèse est centrée sur les sites de stockage de l’hélium et l’argon, et leurs mécanismes de diffusion dans les roches mantelliques. Des échantillons d’olivine polycristalline ont été dopés en hélium et argon à haute température (1150 ± 25 and 1050 ± 25 °C) et haute pression (0.30 ± 0.01 GPa), et analysés par chauffage par paliers de température avec un spectromètre de masse. L’influence d’une concentration initiale hétérogène dans l’échantillon sur les diffusivités calculées a également été testée, démontrant la robustesse des paramètres de diffusion obtenus dans cette étude. Les résultats montrent que deux domaines de diffusion sont présents dans l’olivine polycristalline : (i) un domaine à haute température avec une énergie d’activation (Ea) élevée où la diffusion est contrôlée par la diffusion dans la maille cristalline, et (ii) un domaine à plus basse température avec une Ea plus faible où la diffusion est contrôlée par à la fois la diffusion dans la maille cristalline et celle dans les joints de grains. Ces deux domaines sont séparés par une température de transition qui a lieu au moment où les joints de grains ont été vidés. Mes résultats confirment que les joints de grains peuvent représenter un site de stockage significatif pour l’hélium et l’argon. Pour l’hélium, deux populations d’Ea ont été observées dans le domaine de la maille cristalline de l’olivine, interprétées comme correspondant à la diffusion de l’hélium dans les sites interstitiels (Ea = 95 ± 15 kJ.mol-1) et dans les sites vacants du Mg (Ea = 168 ± 19 kJ.mol-1). Pour l’argon, une valeur moyenne des paramètre de diffusion dans la maille cristalline (Ea = 166 ± 44 kJ.mol-1 et logD0 = −7.04 ± 1.13 avec D0 en m2.s-1) a été obtenue à partir des données de la littérature et de notre étude. De plus, les paramètres de diffusion dans les joints de grains ont été déterminés : Ea = 45 ± 12 kJ.mol-1 et D0 = 5.30 ± 1.53 * 10-13 m2.s-1 pour l’hélium, et Ea = 22 ± 5 kJ.mol-1 et log(D0) = -12.33 ± 0.3 pour l’argon avec D0 en m2.s-1. En appliquant ces résultats au manteau supérieur, il s’avère qu’une quantité conséquente d’hélium et d’argon peut être stockée aux joints de grains (~ 22% pour une taille de grain de 1 mm). En conséquence, les diffusivités globales peuvent être significativement plus élevées que celles de la maille cristalline, induisant des implications importantes pour la géochimie et la géodynamique du manteau terrestre
Noble gases are key tracers of mantle geochemical and isotopic heterogeneities and can constrain our understanding of mantle geodynamics. Nevertheless, the basic mechanisms of noble gas storage and transport in mantle minerals remain poorly understood. In this PhD thesis, I focused on helium and argon to constrain their storage sites and the diffusive mechanisms, which occur in mantle rocks. Polycrystalline olivine was doped with helium and argon at high temperature (1150 ± 25 and 1050 ± 25 °C) and high pressure (0.30 ± 0.01 GPa), followed by step heating extraction experiments. I also tested the effect of heterogeneous initial concentrations on the extracted diffusivities, and demonstrate the robustness of diffusion parameters obtained in this study. My results show that two diffusion domains are present in polycrystalline olivine: (i) a high temperature domain with high activation energy (Ea) where diffusion is only controlled by lattice diffusion, and (ii) a lower temperature domain with lower Ea where diffusion is controlled by both grain boundary and lattice diffusion. These two domains are separated by a transition temperature that depends on the depletion of helium or argon hosted in grain boundaries, i.e., the amount of helium or argon stored at grain boundaries and the temperature and duration of the step heating sequence. The results confirm that grain boundaries can represent a significant storage site for helium and argon. Moreover, I constrained argon and helium diffusion in olivine lattice. For helium, I report two different populations of Ea in the lattice diffusion domain, which are interpreted as diffusion in interstitials (Ea = 95 ± 15 kJ.mol-1) and Mg vacancies (Ea = 168 ± 19 kJ.mol-1). For argon, a mean value of diffusion parameters in olivine lattice (Ea = 166 ± 44 kJ.mol-1 and logD0 = −7.04 ± 1.13 with D0 in m2.s-1) is obtained for data from literature and this study. Furthermore, I determine grain boundary diffusion parameters: Ea = 45 ± 12 kJ.mol-1 and D0 = 5.30 ± 1.53 * 10-13 m2.s-1 for helium, and Ea = 22 ± 5 kJ.mol-1 and log(D0) = -12.33 ± 0.3 for argon with D0 in m2.s-1. Applying these results to the upper mantle reveals that high content of helium and argon can be stored at grain boundaries. As a consequence, bulk diffusivities can be significantly higher than lattice diffusivities, inducing important implications for mantle geochemistry and geodynamics

APA, Harvard, Vancouver, ISO, and other styles

34

Mikac, Katarina Maryann, and n/a. "The population genetics of the invasive Psocoptera (Liposcelididae) species Liposcelis bostrychophila Badonnel and Liposcelis decolor (Pearman) in Australian grain storage systems." University of Canberra. Institute of Applied Ecology, 2006. http://erl.canberra.edu.au./public/adt-AUC20070301.154014.

Full text

Abstract:

This thesis is a comprehensive treatment of the invasion genetics of two major Liposcelis pest species, Liposcelis bostrychophila Badonnel and L. decolor (Pearman), in Australian grain storage systems. Randomly amplified polymorphic DNA (RAPDs) and microsatellite DNA markers were used to investigate Liposcelis invasions in grain storage systems. The RAPD and microsatellite markers used provided insights into the genetic diversity of L. bostrychophila and L. decolor populations both in Australia and internationally, providing information integral to gaining an understanding of Liposcelis invasions in Australian grain storage systems. The thesis is divided into discrete chapters, and for each chapter an abstract is provided. Chapter 1 provides background on Liposcelis invasions in Australia in relation to the biology of Liposcelis species, the infrastructure of the Australian grain industry and the history of invasions in comparison to other invasive invertebrate species. The use of DNA and PCR technologies to investigate Liposcelis invasions are discussed and the aims and objectives of this thesis are introduced. Chapter 2 uses RAPDs to trace the geographic origin of L. bostrychophila populations in Australia from unknown geographic sources internationally. High levels of clonal genetic diversity among populations of L. bostrychophila in Australia and internationally were found. In addition, multiple introductions, from a wide range of international source populations were detected and this obscured our ability to accurately determine the geographic origin of L. bostrychophila in Australia. Given the high clonal genetic diversity found in populations of parthenogenetic L. bostrychophila in Australia, diagnostic Wolbachia PCR primers were used in Chapter 3 to investigate whether L. bostrychophila individuals from these populations were infected by Wolbachia and if infected, to investigate the strain of Wolbachia characteristic of Australian L. bostrychophila populations. Results from Chapter 3 provide the first evidence of multiple Wolbachia infection from strains A and B in Australian L. bostrychophila populations. Chapter 4 details the extensive molecular procedures undertaken to isolate microsatellite loci from Liposcelis decolor using both enrichment and nonenrichment methods. Microsatellite loci were optimised for use in PCR in single individuals following extensive troubleshooting. Troubleshooting efforts focused on elucidating the factors controlling the specificity, efficiency and sensitivity of the PCR to amplify small Liposcelis individuals known to be rich in lipids and proteins, all inhibitory to PCR. In Chapter 5 lipids and proteins were investigated from L. decolor and L. entomophila to determine total concentrations and characterize the lipids from these species. This chapter discusses whether the lipid and protein concentrations found were of a level that could be inhibitory to PCR in relation to the microsatellite techniques used in this study. From the work conducted in both Chapters 4 and 5 a troubleshooting protocol adapted for use in L. decolor was developed and implemented to determine the endogenous and exogenous parameters responsible for the function and reproducibility of PCR of microsatellite loci in L. decolor. In Chapter 6, the novel microsatellites isolated from L. decolor in Chapter 4 were used to investigate genetic structure and gene flow from Australian and international L. decolor populations. In Chapter 6 the first evidence of population differentiation, gene flow and dispersal in invasive populations of L. decolor was found. In addition, the eleven microsatellites isolated from L. decolor were cross-amplified in five other important Liposcelis pests, L. bostrychophila, L. entomophila, L. paeta, L. rufa, and L. corrodens, from which informative population genetic studies are now possible. Finally, Chapter 7 comprises the thesis synopsis, implications and future research.

APA, Harvard, Vancouver, ISO, and other styles

35

Martin, Benjamin A. "TWO ESSAYS ON WHOLE FARM MODELING AND CROP MARKETING IN WESTERN KENTUCKY." UKnowledge, 2018. https://uknowledge.uky.edu/agecon_etds/65.

Full text

Abstract:

This thesis is composed of two essays that investigate whole farm planning and crop marketing in western Kentucky. In the first essay, contracting decisions between food corn producers and a mill are analyzed to observe factors affecting the bushel amount farmers contract. Unbalanced panel data containing seven years’ worth of pricing and contract information are used with a fixed-effects model to generate parameter estimates and quantify their effect on bushels contracted. It was found that contract attributes, market condition, and relationship-specific assets had a significant effect on producers’ food corn contracting decisions. The second essay utilizes mixed-integer programming to optimize resource allocation and marketing strategy for a hypothetical farm. Post-optimal analysis is performed to determine non-binding capacities for drying and storage equipment. The model is re-run with these non-binding capacities to observe changes in net returns as well as planting, harvesting, and marketing strategies. New equipment and associated costs are identified, and the change in net returns from the base case is used as net cash flow in a net present value investment analysis. Results of the investment analysis indicate increasing drying and storage capacity is a wise investment given the scenario modeled.

APA, Harvard, Vancouver, ISO, and other styles

36

Bonnot, Titouan. "Réponse du grain de blé à la nutrition azotée et soufrée : étude intégrative des mécanismes moléculaires mis en jeu au cours du développement du grain par des analyses -omiques." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22767/document.

Full text

Abstract:

L’augmentation des rendements est un enjeu majeur chez les céréales. Dans cet objectif, il est nécessaire de maintenir la qualité du grain de blé, qui est principalement déterminée par sa teneur et sa composition en protéines de réserve. En effet, une forte relation négative existe entre le rendement et la teneur en protéines. Par ailleurs, la qualité du grain est fortement influencée par la disponibilité en azote et en soufre dans le sol. La limitation des apports d’intrants azotés à la culture et la carence en soufre récemment observée dans les sols représentent ainsi des difficultés supplémentaires pour maitriser cette qualité. Une meilleure connaissance des mécanismes moléculaires impliqués dans le contrôle du développement du grain et la mise en place de ses réserves protéiques en réponse à la nutrition azotée et soufrée est donc primordiale. L’objectif de cette thèse a ainsi été d’apporter de nouveaux éléments à la compréhension de ces processus de régulation, aujourd’hui peu connus. Pour cela, les approches -omiques sont apparues comme une stratégie de choix pour identifier les acteurs moléculaires mis en jeu. Le protéome nucléaire a été une cible importante dans les travaux menés. L’étude de ces protéines nucléaires a révélé certains régulateurs transcriptionnels qui pourraient être impliqués dans le contrôle de la mise en place des réserves du grain. Dans une approche combinant des données de protéomique, transcriptomique et métabolomique, une vision intégrative de la réponse du grain à la nutrition azotée et soufrée a été obtenue. L’importance d’un apport de soufre dans le contrôle de la balance azote/soufre du grain, déterminante pour la composition du grain en protéines de réserve, a été clairement vérifiée. Parmi les changements observés au niveau du métabolisme cellulaire, certains des gènes affectés par la modification de cette balance pourraient orchestrer l’ajustement de la composition du grain face à des situations de carences nutritionnelles. Ces nouvelles connaissances devraient permettre de mieux maitriser la qualité du grain de blé dans un contexte d’agriculture durable
Improving the yield potential of cereals represents a major challenge. In this context, wheat grain quality has to be maintained. Indeed, grain quality is mainly determined by the content and the composition of storage proteins, but there is a strongly negative correlation between yield and grain protein concentration. In addition, grain quality is strongly influenced by the availability of nitrogen and sulfur in soils. Nowadays, the limitation of nitrogen inputs, and also the sulfur deficiency recently observed in soils represent major difficulties to control the quality. Therefore, understanding of molecular mechanisms controlling grain development and accumulation of storage proteins in response to nitrogen and sulfur supply is a major issue. The objective of this thesis was to create knowledge on the comprehension of these regulatory mechanisms. For this purpose, the best strategy to identify molecular actors involved in these processes consisted of -omics approaches. In our studies, the nuclear proteome was an important target. Among these proteins, we revealed some transcriptional regulators likely to be involved in the control of the accumulation of grain storage compounds. Using an approach combining proteomic, transcriptomic and metabolomic data, the characterization of the integrative grain response to the nitrogen and sulfur supply was obtained. Besides, our studies clearly confirmed the major influence of sulfur in the control of the nitrogen/sulfur balance that determines the grain storage protein composition. Among the changes observed in the cell metabolism, some genes were disturbed by the modification of this balance. Thus these genes could coordinate the adjustment of grain composition in response to nutritional deficiencies. These new results contribute in facing the challenge of maintaining wheat grain quality with sustainable agriculture

APA, Harvard, Vancouver, ISO, and other styles

37

Fernandes, Queli Silvério. "Análise da capacidade estática de armazenagem de grãos no Brasil no período de 1980 a 2015." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6417.

Full text

Abstract:

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2016-10-18T17:04:13Z No. of bitstreams: 2 Dissertação - Queli Silvério Fernandes - 2016.pdf: 1375648 bytes, checksum: 2802e9c975aac50366bae452d23a7cc8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-10-18T17:05:07Z (GMT) No. of bitstreams: 2 Dissertação - Queli Silvério Fernandes - 2016.pdf: 1375648 bytes, checksum: 2802e9c975aac50366bae452d23a7cc8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2016-10-18T17:05:07Z (GMT). No. of bitstreams: 2 Dissertação - Queli Silvério Fernandes - 2016.pdf: 1375648 bytes, checksum: 2802e9c975aac50366bae452d23a7cc8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-09-26
This study has as objective analyze the evolution of the static capacity of grain storage in Brazil by region, compared to the production, from 1980 to 2015. This is a research exploratory in descriptive character, and the technical procedure used was documentary analysis of public reports National Supply Company - CONAB. Data were analyzed in statistical program Statistical Package for Social Sciences - SPSS, version 22.0. Firstly for to analyze the evolution of static storage capacity and of grain yield per region in Brazil, from 1980 to 2015, were performed polynomial regressions. In the second analysis we observed the correlation between the static capacity and the grain production by region, from 1980 to 2015, using the Spearman correlation test, and, to analyze the occurrence of deficit or surplus storage by region was accomplished calculating percentage. Lastly was it described the present situation of the location of warehouses and the predominant type of storage unit in each region. Is Significant the increased static storage capacity of concentrate grains in the last 15 years, however, in disproportion with the rhythm to the rate of growth presented in grain production, presenting static capacity below the production in four regions, being them the Midwest, South, Northeast and North. Already the Southeast region has a higher static capacity than the capacity productive current. In Brazil it was observed since 2002 the increase in the deficit of static capacity of storage which in 2015 presented a value of 26%. In Brazil only 14% of the static capacity of storage is located on farms and most of the static capacity concentrates on units collecting and intermediate.
Este estudo tem como objetivo analisar a evolução da capacidade estática de armazenagem de grãos no Brasil por região, comparando com a produção, no período de 1980 a 2015. Esta é uma pesquisa exploratória de caráter descritivo, e o procedimento técnico utilizado foi a análise documental dos relatórios públicos da Companhia Nacional de Abastecimento - CONAB. Os dados foram analisados no programa estatístico Statistical Package for Social Sciences - SPSS, versão 22.0. Primeiramente para análise da evolução da capacidade estática de armazenagem e da produção de grãos por região do Brasil, no período de 1980 a 2015, foram realizadas regressões polinomiais. Em segunda análise observou-se a correlação entre a capacidade estática e a produção de grãos por região, no período de 1980 a 2015, com a utilização do teste de correlação de Spearman, e, para analisar a ocorrência de déficit ou superávit de armazenagem por região foi realizado cálculo em porcentagem. Por último foi descrita a atual situação da localização dos armazéns e do tipo de unidade armazenadora predominante em cada região. É significativo o aumento da capacidade estática de armazenagem de grãos concentrado nos últimos 15 anos, porém, em desproporção com o ritmo da taxa de crescimento apresentado na produção de grãos, estando com a capacidade estática de armazenagem inferior a produção em quatro regiões sendo Centro-Oeste, Sul, Nordeste e Norte. Já a região Sudeste apresenta maior capacidade estática que a atual capacidade produtiva. No Brasil observou-se desde 2002 o aumento do déficit da capacidade estática de armazenagem que em 2015 apresentou o valor de 26%. No Brasil somente 14% da capacidade estática de armazenagem está localizada nas fazendas e a maior parte da capacidade estática se concentra nas unidades coletoras e intermediárias.

APA, Harvard, Vancouver, ISO, and other styles

38

Simoes, Larraz Ferreira Mariana. "Dynamique d’assemblage des protéines de réserve et du remplissage du grain de blé dur." Thesis, Montpellier, SupAgro, 2011. http://www.theses.fr/2011NSAM0009/document.

Full text

Abstract:

Le blé dur, du fait de sa vitrosité et de sa richesse en protéines est particulièrement adapté àla fabrication des pâtes alimentaires. Cette céréale, largement cultivée dans le bassinméditerranéen, est fréquemment soumise à des stress hydriques et thermiques. Les objectifsde cette thèse ont été d'approfondir les connaissances sur les modalités d'accumulation etd'assemblage des protéines de réserve au cours du développement du grain. Un suivi fin duremplissage du grain, de la morphologie des corps protéiques, des changements d'état redox etde la distribution en taille des polymères de gluténines a été réalisé. L'influence, sur cesdifférents paramètres, de températures élevées appliquées à différents stades dedéveloppement du grain a été étudiée.En privilégiant l'accumulation des protéines au détriment de l'amidon, le stress thermiquejoue un rôle non négligeable dans l'obtention de grains vitreux et à fortes teneurs en protéines.L'arrêt de la croissance du grain, observé à 45% de teneur en eau, est précédé de la mise enplace de la matrice protéique. L'accumulation de la matière sèche apparaît étroitement liée à ladynamique de l'eau, confirmant le lien entre teneur en eau et poids final du grain. Au cours duremplissage du grain, les températures élevées exercent un effet significatif sur la formationdes polymères de gluténines insolubles dans le SDS. Leur formation n'intervient qu'en fin dedessiccation et en deçà de 30% de teneur en eau. La durée de cette phase ultime d'oxydation etd'assemblage des polymères de gluténines a été reliée à la teneur en protéines.L'évolution du statut redox du grain montre qu'une accumulation massive de polymères degluténines intervient juste avant l'entrée en dessiccation du grain qui coïncide avecl'effondrement de l'ascorbate dans le grain. Coïncidant avec cette oxydation manifeste, unphénomène de glutathionylation des protéines a été détecté avec une rupture de l'activité de laCAT. Au cours de la dessiccation, les activités de la SOD et de la GR augmentent de façonsignificative. Cette synthèse tardive pourrait se produire au niveau de la couche à aleurone etdu germe en réponse à l'oxydation massive de l'albumen.Enfin, nous avons analysé le couplage entre oxydation des thiols protéiques et croissance entaille des polymères de gluténines. Très précocement, les sous-unités de gluténiness'assemblent sous forme d'oligomères partiellement réduits. Durant le remplissage du grain,une oxydation massive des thiols intervient avec la formation de polymères majoritairementcomposés de SG-HPM sur lesquels viendraient se fixer les SG-FPM. Au cours de la dessiccation,la taille des polymères augmente. Les structures polymériques formées au cours del'élaboration du grain possèdent un nombre de cystéines réduites élevé et incompatible avecun modèle d'assemblage linéaire. Les résultats obtenus nous permettent de proposer unrepliement tardif des SG-FPM, postérieur à leur insertion dans les assemblages oligomériques.Ils nous amènent à mettre en avant le rôle du glutathion comme co-facteur de la genèse despolymères, à l'opposé des thèses classiques qui en font plutôt un inhibiteur de la croissance entaille des polymères de gluténines
Durum wheat is particularly recognized as the most suitable raw material for pasta makingdue to its vitreousness and its high protein content. This cereal is commonly grown inMediterranean environment and then frequently submitted to high temperature and waterstress. The aim of this thesis was to better understand the accumulation and assembly ofstorage proteins during the grain development. Evaluation of the grain filling, the morphologyof protein bodies, the redox status and the size distribution of glutenin polymers were carriedout. The effect of high temperatures applied at different stages of the grain development onthese parameters was studied.By favouring protein accumulation at the expense of starch, heat stress appeared essentialto obtain vitreous grains and high protein content. The arrest of grain growth observed at 45%grain water content is preceded by the formation of a continuous protein matrix. The dry massaccumulation is closely related to water dynamics, confirming the link between water contentand final grain weight. During grain filling, high temperatures have a significant effect on theformation of SDS-insoluble glutenin polymers. It occurred when grain water concentrationdropped below 30%. The duration of this final stage of oxidation and assembly of gluteninpolymers was related to protein content.Changes in the grain redox status showed an accumulation of glutenin polymers mainlyoccurring before the onset of grain desiccation phase and coinciding with the ascorbateoxidation. This clear oxidation coincided also with the glutathionylation of proteins and thedrop of the CAT activity. During desiccation, the activities of SOD and GR increased significantly.This late synthesis could occur in the aleurone layer and germ in response to massive oxidationof the endosperm cells.Finally, we evaluated the coupling between protein thiol oxidation and size increase ofglutenin polymers. In the early stages, glutenin subunits assembled as oligomers partiallyreduced. During grain filling, a strong thiol oxidation took place with the formation of polymersmainly composed of HMW-GS associated with LMW-GS branching. The polymer size increasedduring desiccation. The polymeric structures obtained during the grain development presenteda high number of reduced cysteines inconsistent with a linear concatenation model ofassembly. It allowed us to propose that the folding of LMW-GS is a late event, subsequent totheir insertion into oligomeric assemblies. These results highlighted the role of glutathione asco-factor in the polymers formation, contrasting with the common assumption that considers itas an inhibitor of the size increase of glutenin polymers

APA, Harvard, Vancouver, ISO, and other styles

39

Frederick, Jennifer Leanne. "Heat treatment of empty storage bins and grain-processing facilities: factors influencing efficacy against adults of the red flour beetle, Tribolium castaneum (Herbst)." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32894.

Full text

Abstract:

Doctor of Philosophy
Department of Grain Science and Industry
Subramanyam Bhadriraju
Hulya Dogan
Heat treatment, a more than 100-year-old technology, involves raising the ambient temperature of a an empty bins/storage space or a clean gran-processing facility to 50-60°C for 24 h or less to kill stored-product insects. Heat treatment is an environmentally benign and a safer alternative to chemical insecticides. The studies reported here were conducted to determine the effect of short-term exposure to sub-lethal temperatures on adults of Tribolium castaneum (Herbst) and their subsequent susceptibility to temperatures of 50 and 55°C for 60 and 15 min, respectively; to determine the effect of rearing T. castaneum at select elevated temperatures for 10 generations on their subsequent susceptibility to temperatures of 50 and 55°C; to determine the effects of age and sex on susceptibility of T. castaneum adults to 50 and 55°C; and to determine the effectiveness of a diatomaceous earth (DE) formulation at several elevated temperatures below 50°C on the mortality of T. castaneum adults. Results of the studies showed that short-term exposure between 24 and 72 h, to sub-lethal temperatures (32, 36, and 40°C) only increased survival for insects acclimated to 32°C. Acclimation at 36 and 40°C resulted in higher mortality after exposure for 24, 48, and 72 h at 50 and 55°C. Rearing insects at 32 and 36°C for 10 generations resulted in the highest survival of adults at 50°C. However, when adults reared at 32°C were exposed during heat treatment of Hal Ross Flour Mill, the adults were least susceptible to dynamically changing temperatures over time. Female T. castaneum adults were more heat tolerant than males, and adults 1 d post-emergence were the most heat tolerant when exposed to 55°C for 15 minutes compared with adults aged 7-42 d. The efficacy of DE was enhanced at higher constant temperatures, which can lessen energy inputs in order to obtain a complete kill of insects when temperatures do not reach 50°C or greater. Given the changing climate, it is very useful for researchers to understand the implications of increasing temperatures on the heat tolerance of insects.

APA, Harvard, Vancouver, ISO, and other styles

40

FERNANDEZ, ANTONIO P. R. "Estudo das características elétricas e microestruturais de supercapacitores para armazenamento de energia." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26824.

Full text

Abstract:

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T16:52:08Z No. of bitstreams: 0
Made available in DSpace on 2016-11-11T16:52:08Z (GMT). No. of bitstreams: 0
Esta dissertação tem por objetivo reportar dados relativos às características elétricas e microestruturais de eletrodos aplicadas em dispositivos armazenadores de energia, especificamente supercapacitores constituídos por eletrodos de carvão ativado. Os parâmetros elétricos estudados foram a resistência em série equivalente obtida pelo método da interrupção de corrente (ESR(Inst)) (sendo que a sigla ESR é oriunda do termo inglês Equivalent Series Resistance), a resistência em paralelo equivalente (EPR(Dep)) obtida pelo método do valor dependente (sendo que a sigla EPR é oriunda do termo inglês Equivalent Parallel Resistance) e a capacitância (C(DC)) obtida pelo método da corrente contínua (sendo que a sigla DC oriunda do termo inglês Direct Current). Tais parâmetros foram escolhidos devido ao impacto que causam no tempo de vida útil, na capacidade de armazenamento de cargas elétricas, na velocidade de carga e descarga, na perda por efeito termoiônico nos processos de carga e descarga e na perda de cargas armazenadas devido à autodescarga em supercapacitores. Os dados microestruturais reportam por meio de imagens a homogeneidade da porosidade e por meio de valores correlacionados a composição química e eventuais contaminações presentes nos eletrodos. Os dados e valores coletados possuem a intenção de servir como referência comparativa de qualidade e apontar qual parâmetro afeta mais a qualidade do supercapacitor. Para tanto foram realizados testes a fim de coletar valores de C(DC), ESR(Inst) e EPR(Dep) após a exposição de supercapacitores de 1F/5,5V a temperaturas de 50ºC, 75ºC, 100ºC e 125ºC por 672 horas, sendo os dados coletados ao inicio dos testes, à temperatura ambiente, e posteriormente a cada 168 horas. Feitos os experimentos concluiu-se que o parâmetro que sofreu maior deterioração com o acréscimo de energia térmica foi a EPR(Dep), em seguida a C(DC), que de fato pouco sofreu alteração e a ESR(Inst), em que a mudança dentro do erro de medição foi imperceptível.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO, and other styles

41

Olstorpe, Matilda. "Feed grain improvement through biopreservation and bioprocessing : microbial diversity, energy conservation and animal nutrition aspects /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200877.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Aperavičiūtė, Vaida. "Skirtingų veislių žieminių kviečių (Triticum aestivum L.) laikomų grūdų kokybės rodiklių palyginimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140613_102223-82018.

Full text

Abstract:

Tyrimo objektas žieminių kviečių veislių 'Julius', 'Leifer', 'Operetka' ir 'Skagen' technologinių savybių kitimas laikymo metu. Tyrimo tikslas ištirti skirtingų veislių žieminių kviečių technologinių savybių kitimo dėsningumus priklausomai nuo laikymo trukmės. Uždaviniai 1. Ištirti skirtingų veislių žieminių kviečių grūdų kokybę tik nuėmus derlių. 2. Įvertinti laikomų grūdų kokybę. 3. Apibendrinti grūdų technologinių savybių kitimo dėsningumus. Tyrimo metodai 2012–2013 m. Pakruojo rajone buvo auginti kviečiai. Žieminių kviečių derlius nuimtas 2013 m. rugpjūčio 20 d. Atlikti kviečių kokybės rodiklių tyrimai. Standartiniais metodais ištirta: grūdų drėgnis, baltymų, šlapiojo glitimo, krakmolo kiekis, sedimentacijos rodiklis, kritimo skaičius, piltinis tankis, pesticidų likučiai. Vėliau kviečių mėginiai laikomi Diliauskų elevatoriuje, sandėlyje dėžutėse po 4 kg, trimis pakartojimais. Kas mėnesį atliekami kviečių rodiklių kokybės tyrimai. Tyrimo rezultatai. Žieminių kviečių auginimo agrotechnikoje naudojant pesticidus pagal rekomendacijas ir prisilaikant leidžiamų normų, pesticidų likučiai grūduose nesikaupia. Laikant sausus grūdus sandėlyje jų drėgmė padidėja, baltymų kiekis ir saiko svoris nesikeičia. Glitimo kiekis laikomuose žieminiuose kviečiuose padidėjo nežymiai. Krakmolo kiekis laikomuose žieminiuose kviečiuose didėjo vidutiniškai 1,3 %. Laikymo laikotarpiu sedimentacijos vertės žieminiuose kviečiuose mažėjo, vidutiniškai 6,45 ml. Kritimo skaičius turėjo tendensiją... [toliau žr. visą tekstą]
Research object winter wheat varieties 'Julius', 'Leifer', 'Operetka' and 'Skagen' technological characteristics change during storage. Research aim explore the different varieties of winter wheat technological properties change dependent on the storage time. Objectives 1. First investigate the different varieties of winter wheat grain quality after the harvest. 2. Evaluate the quality of stored grain. 3. Summarize the technological properties of grain variation patterns. Research methods 2012-2013 year Pakruojo area were grown winter wheat. Winter wheat harvested in 2013 August 20 d. Perform quality in wheat research. Analyzed by standard methods of grain moisture content, protein, wet gluten, starch content, sedimentation value, falling number, bulk density, pesticide residues. Winter wheat samples kept in Diliauskų elevators, stock boxes of 4 kg, with three replications. Monthly indicators made of wheat quality tests. Research results. Winter wheat agricultural equipment, the use of pesticides in accordance with guidelines and in compliance with the allowable limits of pesticide residues in grain accumulation. Keeping dry grain stock of humidity increases the protein content moderation and weight does not change. Gluten content stored in winter wheat increased slightly . The starch content is stored in winter wheat increased an average of 1, 3 % . The storage period of sedimentation values in winter wheat decreased an average of 6, 45 ml . Falling number was... [to full text]

APA, Harvard, Vancouver, ISO, and other styles

43

Daňhelová, Martina. "Logistický řetězec zemědělských komodit." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-85321.

Full text

Abstract:

Diploma thesis "The logistic chain of agricultural commodities" is focused on the analysis of material flow in agricultural sector. Work assesses the benefits of storing commodities after harvest or sale of produce without adjustment from field. The study evaluates the economic and process performance in terms of processing of agricultural commodities after harvest from the beginning to final option trading. The obtained data will be possible to assess benefits of storing commodities. In the practical part is analyzed profitability of investment i post-harvest lines and sets out proposal to stremline the logistics chain of commodities within the company DAŇHEL AGRO a.s.

APA, Harvard, Vancouver, ISO, and other styles

44

Ferrasa, Marcelo [UNESP]. "Sistema de monitoramento de temperatura e umidade em silos graneleiros via rádio." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/101702.

Full text

Abstract:

Made available in DSpace on 2014-06-11T19:31:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-01Bitstream added on 2014-06-13T19:20:45Z : No. of bitstreams: 1 ferrasa_m_dr_botfca.pdf: 4410782 bytes, checksum: b6c63787a174343b26f5a0ba21755f4b (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O uso das Tecnologias da Informação e Comunicação tem crescido nas mais variadas atividades agrícolas. Como conseqüência, vem revolucionando a forma de pensar e agir do produtor que almeja se estabelecer em um mercado cada vez mais competitivo. Entretanto, o alto custo de aquisição e manutenção dessas tecnologias é um fator que pode inibir sua disseminação e aceitação, principalmente a um grande número de pequenos produtores de grãos. Diante desse cenário, há uma necessidade de soluções inovadoras adequadas a esse universo de produtores. Partindo-se dessa premissa, este trabalho apresenta o desenvolvimento de um protótipo de baixo custo para o monitoramento de temperatura e umidade de grãos armazenados em silos, utilizando uma tecnologia de comunicação sem fio por radiofreqüência. Para tanto, foram analisadas as implicações econômicas de custo/benefício do emprego inovador da transmissão sem fio no processo de termometria de grãos. O protótipo foi composto por duas unidades eletrônicas, uma de aquisição e outra de recepção de dados, além de um programa computacional que ofereceu ao produtor informações mais precisas para o controle da aeração. Por meio de testes realizados quanto à estabilidade, integridade e confiabilidade da transmissão de dados via rádio, utilizando componentes eletrônicos de baixo custo, pode-se considerar o sistema desenvolvido potencialmente viável. Este apresentou o diferencial da comunicação sem fio via rádio no processo de termometria de grãos, proporcionando mobilidade, minimizando custos com cabeamento, manutenção e oferecendo facilidades para sua expansão; também adequou-se ao monitoramento de temperatura eumidade de grãos em silos; e mostrou-se com viabilidade operacional, além do baixo custo de desenvolvimento quando comparado a produtos similares encontrados no mercado brasileiro.
The use of Information and Communication Technology has grown in most agricultural activities. As a consequence, it has changed the way of thinking and acting of the farmer who wants to establish in a more and more competitive market. However, the high costs of acquisition and maintenance of those technologies may be a factor which can inhibit its spread and acceptance, mainly to a large number of small grain Brazilian farmers. In this context, there is a need for innovative solution which are proper for this universe of farmers. Starting from this premise, this paper presents the development of a low cost prototype to the monitoring process of temperature and humidity values of grains stored in silos, using communication based on wireless technology by radio frequency. Therefore, the economic implications of cost/benefit ratio of innovative application of wireless transmission in the process of thermometry of grains were analysed. The prototype was made of two electronic units, one of acquisition and another one of data reception, as well as a computational software, which offered the farmer more precise information for the control of aeration. By means of stability, integrity and reliability tests of data transmission via radio, using low cost electronic components, the development system can be considered as potentially viable. It presented the difference regarding the wireless communication via radio in the process of grains thermometry, providing mobility, reducing cabling costs and maintenance, and also offering an easy system expansion; it was also appropriate to temperature and humidity monitoring in grain silos; and revealed operational viability, besides 4 the low cost development when compared to similar products available in the Brazilian market.

APA, Harvard, Vancouver, ISO, and other styles

45

Lusse, Johan. "Voedselrisikobestuur tydens die opberging en hantering van graan in Overberg Agri." Thesis, Stellenbosch : Stellenbosch University, 2006. http://hdl.handle.net/10019.1/49227.

Full text

Abstract:

Thesis (MBA)--Stellenbosch University, 2006.
ENGLISH ABSTRACT: Grains are generally considered to be low risk products. However food safety laws and consumer demands require companies to implement programs that will ensure food safety. To comply with these demands, South African grain handling companies are required to implement appropriate risk management systems. Companies that do not adopt such systems will not only exclude themselves from international grain markets but also from the whole food industry with related losses in market share. This study involved consultation with various roieplayers in the grain industry and a literature study to determine the current status of food risk management systems in South Africa. The survey investigated the food risk management requirements of local grain handling companies, and how local and international companies manage food risks. Existing food risk management practices currently implemented by Overberg Agri were also analysed. Although Overberg Agri's grain division has been handling grain for many years, attention to quality, safety en food risk factors has been infonnal and fragmented. No formal documented food risk management system has been implemented. This study presents an integrated food risk management system for managing food quality and food safety. The management system aims at identifying all important processes which are to be managed, to formally document the processes and to provide guidelines for implementing the system. Adoption of such an approach would ensure that the system is implemented in a structured way and that processes are regularly reviewed and updated as required in an ever-changing business environment. The management system contains the implementation of a system that includes food quality~ safety and risk, but includes more than just the minimum requirements of the ISO 9001 and Codex standards. The proposed management system focusses on an approach based on logical sequence of the daily business, to involve everyone and keep them involved. This will ensure that processes are executed in a manner that will identify all food risks to limit or exclude them, rather than analysing each element of an existing standard and repeating it as a requirement. The existing management system of Overberg Agri is not effective in managing food risks because several losses still occure. This is because there are insufficient formal systems, documentation and records available to determine wheter losses can be ascribed to structures, work instructions, management or latent grain defects. The proposed system will ensure that the above mentioned will be implemented to supply the company, stakeholders en clients with sound information which is needed for continuous improvement of the company.
AFRIKAANSE OPSOMMING: Oor die algemeen word graan as veilige voedsel beskou. Verbruikers dring al meer daarop aan dat ondememings moet bewys dat hulle stelsels in plek het vir die versekering van veilige voedsel. Om aan die vereistes te voldoen, moet ondememings in Suid-Afrika wat graan hanteer, die gepaste risikobestuurstelsels implementeer. Ondernemings wat dit nie doen, stel hulself bloot aan verliese sowel as uitsluiting, nie net van die intemasionale graanhandel nie, maar ook die hele voedselindustrie. Vir die studie is rolspelers in die graanindustrie genader en literatuur bestudeer om vas te stel wat in Suid-Afrika ten opsigte van voedselrisikobestuur bestaan. Daar is ook vasgestel wat die behoeftes ten opsigte van risikobestuur is vir ondememings wat graan opberg en hanteer en wat plaaslike en internasionale ondememings doen om voedselrisiko's te bestuur. Ook is bepaal wat alreeds in Overberg Agri se graanafdeling rakende voedselrisikobestuur bestaan. Alhoewel die afdeling al jare funksioneer is daar heelwat plekke waar op informele wyse aandag aan kwaliteit, veiligheid en voedselrisiko gegee word, maar nie formeel nie. Die werkstuk poog daarin om 'n geintegreerde bestuurstelsel vir voedselkwaliteit en - veiligheid daar te stel. Die bestuurstelsel het dit ten doel om alle belangrike prosesse wat bestuur word, te identifiseer en op 'n formele wyse te dokumenteer en te implementeer. Sodoende word seker gemaak dat dit reelmatig gebeur en dat sulke prosesse gereeld hersien word om te sien of hulle noodsaaklik vir die bedryf is. Die bestuurstelsel behels die implementering van 'n stelsel wat voedselkwaliteit, -veiligheid en -risiko insluit, maar meer is as net die absolute minimum vereistes van die ISO 9001 en die Codex standaard. Hiervoor kombineer die voorgestelde bestuurstelsel die ISO 9001 en HACCP standaarde. Die bestuurstelsel konsentreer meer op 'n benadering gebaseer op 'n logiese volgorde soos die besigheid daagliks vloei, en om almal betrokke te kry en te hou, en dan te verseker dat prosesse so uitgevoer word dat alle voedselrisiko's geidentifiseer en beperk of uitgesluit word, eerder as om elke element van 'n bestaande standaard te ontIeed en weer te gee as 'n vereiste. Die bestaande bestuurstelsel van Overberg Agri is nie effektief in die bestuur van voedselrisiko's nie, aangesien te veel verliese steeds voorkom. Dit is waarskynlik omdat daar nie genoeg stelsels, dokumentasie en rekords beskikbaar is, sodat oorsake toegeskryf kan word aan strukture, werksinstruksies, bestuur of graan nie. Die voorgestelde stelsel wil verseker dat bogenoemde geimplementeer word om vir die ondememing self, aandeelhouers en kliente konkrete inligting te gee sodat verbetering voortdurend aangebring kan word.

APA, Harvard, Vancouver, ISO, and other styles

46

LIRA, SIMONE MARISA. "IDENTIFYING COMPETITIVE GAINS IN GRAIN POST-HARVESTING WITH INVESTMENT ON OWN STORAGE FACILITIES VERSUS HIRING COOPERATIVE SERVICES: A CASE STUDY IN TWO FARMS IN MATO GROSSO DO SUL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29479@1.

Full text

Abstract:

O agronegócio é um importante setor da economia brasileira pelo incremento que proporciona ao PIB nacional. O País exporta vários produtos agropecuários, sendo líder mundial na produção e venda de soja. O mérito deste sucesso é compartilhado pelos diversos elos que formam sua cadeia de produção e distribuição, elevando a agricultura a patamares de competitividade internacional. Apesar disso, o Brasil apresenta escassa infraestrutura logística, principalmente de armazenagem de grãos em fazendas, que representam elevados investimentos. Somado a um modal rodoviário precário, perdas e desperdícios ocorrem em todo o processo, elevando os custos e dificultando a competição no cenário global. Em vista disso, muitos produtores rurais utilizam serviços de cooperativas. Observa-se que tais serviços são muitas vezes excessivamente custosos ou de reduzida transparência. Assim, a despeito dos elevados recursos envolvidos, e da necessidade de integração de novas atividades no processo da pós-colheita, produtores vêm considerando investir em unidades próprias de armazenagem. Foi realizado um estudo de caso em duas fazendas no Mato Grosso do Sul onde se comparou, pelo método de Custeio Baseado em Atividades (ABC), o cenário atual com uma nova estrutura de integração das etapas pós-colheita. Ademais, o referencial teórico proporcionou um levantamento de ganhos potenciais na comercialização. O método inclui ainda uma avaliação estratégico-mercadológica de outros ganhos complementares. Identificou-se que o investimento em unidade armazenadora de grãos própria gera ganhos potenciais sob as formas de redução de custos, maior liberdade nas decisões da pós-colheita, principalmente na comercialização das safras e um potencial incremento de renda com novos serviços.
Agribusiness is an important sector in the Brazilian economy due to its contribution for the gross national domestic product growth. The country exports several agricultural products and is the world leader in soybean sales. The merit of this success is shared by the various members in the supply chain, which lead the local agriculture to high international levels of competitiveness. However, despite these advances, Brazil has poor infrastructure, especially in farms grain storage facilities. This bottleneck, coupled with a poor road system, result in losses and wastes that occur throughout the production process, increasing costs and reducing competitiveness in a global level. As a result, many farmers hire cooperative services. It is observed that such services are often too costly or of limited transparency. Thus, despite the huge resources involved, and the need for integration of new activities in the post-harvest process, producers consider investing in own storage units. A case study was conducted in the state of Mato Grosso do Sul, using the Activity Based Costing (ABC) as method to compare the current situation of two farms using cooperative post-harvest services with a new structure integrating the post-harvest stages. A literature review on conceptual marketing strategies revealed potential gains with this integration process. The method also includes a strategic-marketing evaluation of other additional gains with the integration. It is concluded that investment in own grain storage units creates potential gains for farmers in the forms of cost savings, freedom for post-harvest sales decisions, and an increase in income with new services.

APA, Harvard, Vancouver, ISO, and other styles

47

Freitas, Romenique da Silva de. "Qualidade de Grãos de Feijão Armazenados sob Atmosfera Modificada." Universidade Federal Rural do Semi-Árido, 2009. http://bdtd.ufersa.edu.br:80/tede/handle/tede/103.

Full text

Abstract:

Made available in DSpace on 2016-08-12T19:15:33Z (GMT). No. of bitstreams: 1 ROMENIQUE DA SILVA DE FREITAS.pdf: 581451 bytes, checksum: fa472168c03c6fa7ac62fde706430995 (MD5) Previous issue date: 2009-03-18
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The study was conducted at the Experimental Farm Rafael Fernandes, Mossoró city, Rio Grande do Norte State, Brazil, with the objective to verify the effect of irrigation levels and planting densities on the castor bean production, BRS ENERGIA . Thus, we used the experimental design in randomized blocks in a split-plot 5 x 2, with four replications. The treatments consisted of irrigation levels (0.6, 0.8, 1.0, 1.2 and 1.4 of ETc) in main plots and plant densities in the sub-plots formed by arrangements 1.50 m x 0.30 m x 0.30 m (D1 - 37,037 plants ha-1) and 1.50 m x 0.30 m x 0.40 m (D2 - 27,778 plants ha-1). The main plots were 18 m in length, 9 m for each of the densities. The irrigation levels were differentiated by the application time using the tubes, each of which had a strip of the water distribution system independent. The main bunches fruits income decreased with the applied levels and the secondary bunches income (in fruits and grains) followed quadratic polynomial model. How much to the total income, was gotten 3,974 kg ha-1 of fruits and 2,691 kg ha-1 of grains with irrigation based on 1,20 and 1,25 of the etc, respectively.
FREITAS, Romenique da Silva. Qualidade de grãos de feijão armazenados sob atmosfera modificada. Mossoró, UFERSA, 2009. 62 f. Dissertação (Mestrado em Agronomia: Fitotecnia) Universidade Federal Rural do Semi-Árido (UFERSA), Mossoró-RN, 2009. Professor Orientador: D. Sc. Patrício Borges Maracajá. Co- orientador: Profa. D. Sc. Lêda Rita D Antonino Faroni. Conselheiros: Prof. D. Sc. Glauber Henrique de Sousa Nunes e Profa. D. Sc. Danila Kelly Pereira Neri. Este trabalho teve por objetivo avaliar a qualidade de grãos de feijão com diferentes teores de água, armazenados em condições herméticas, ao longo do armazenamento. O experimento foi realizado no Setor de Pré-Processamento e Armazenamento de Produtos Agrícolas do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa (UFV). Foram utilizados grãos de feijão (Phaseolus vulgaris L.) do grupo vermelho, cultivar vermelhinho, com teores de água de 12,3, 15,7 e 17,8% b.u., produzidos na safra de inverno (2008), no município de Viçosa-MG. Os grãos foram acondicionados em embalagens herméticas e armazenados em câmara climática, por 0, 30, 60, 90 e 120 dias, à temperatura de 25 °C e umidade relativa de 70±5%. No armazenamento foram utilizadas bolsas plásticas, impermeáveis com capacidade para três quilogramas e garrafas pet transparente com capacidade para 1,5 L. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial com parcelas subdivididas e três repetições, sendo as parcelas representadas pelo fatorial condição de armazenamento (silo tipo bolsa, garrafa pet e testemunha) e teor de água do grão (12,3, 15,7 e 17,8% b.u.) e as subparcelas representadas pelos períodos de armazenamento (0, 30, 60, 90 e 120 dias). Avaliou-se o teor de água, grau de infestação por insetos-praga, massa específica aparente, condutividade elétrica, percentual de germinação, tempo de cocção e classificação dos grãos, após cada período de armazenamento. Todas as variáveis analisadas variaram significativamente (p<0,05) entre os teores de umidade, condições (hermética/não hermética) e períodos de armazenamento. Grãos de feijão com teores de água de 12,3 e 15,7% b.u., armazenados em condições herméticas, mantiveram as características analisadas por 120 dias, exceto o tempo de cocção. Grãos de feijão com teores de água de 17,8% b.u., armazenados em condições herméticas, mantiveram as características analisadas por um período de 60 dias, exceto o tempo de cocção. A perda de qualidade, caracterizada pelo aumento no tempo de cocção, foi maior nos grãos com maior teor de água, armazenados em condições herméticas. Nos grãos com menor teor de água o tempo de cocção foi mantido por 90 dias. O armazenamento hermético é capaz de manter a qualidade de grãos de feijão com teores de água variando de 12,3 a 15,7% b.u. por 120 dias.

APA, Harvard, Vancouver, ISO, and other styles

48

Vincent, Jonathan. "Inférence des réseaux de régulation de la synthèse des protéines de réserve du grain de blé tendre (Triticum aestivum L.) en réponse à l'approvisionnement en azote et en soufre." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22485/document.

Full text

Abstract:

La teneur et la composition en protéines de réserve du grain de blé tendre (Triticum aestivum L.) sont les principaux déterminants de sa valeur d’usage et de sa qualité nutritionnelle. La composition en protéines de réserve du grain est déterminée par la teneur en assimilâts azotés et soufrés par grain via des lois d’échelle qui pourraient être les propriétés émergentes de réseaux de régulation. Plusieurs facteurs de transcription intervenant dans cette régulation ont été mis en évidence, mais les voies et mécanismes impliqués sont encore très peu connus. Le constat est identique en ce qui concerne l’impact de la nutrition azotée et soufrée sur ce réseau de régulation. Le développement des outils de génomique fonctionnelle et de bioinformatique permet aujourd’hui d’aborder ces régulations de manière globale via une approche systémique mettant en relation plusieurs niveaux de régulation. L’objectif du travail présenté est d’explorer les réseaux de régulation –omiques impliqués dans le contrôle de l’accumulation des protéines de réserve dans le grain de blé tendre et leur réponse à l’approvisionnement en azote et en soufre. Une approche d’inférence de réseaux basée sur la découverte de règles a été étendue, implémentée sous la forme d’une plateforme web. L’utilisation de cette plateforme a permis de définir des sémantiques multiples afin d’inférer dans un cadre global, des règles possédant différentes significations biologiques. Des facteurs de transcription spécifiques de certains organes et certaines phases de développement ont été mis en évidence et un intérêt particulier a été apporté à leur position dans les réseaux de règles inférés, notamment en relation avec les protéines de réserve. Les travaux initiés dans cette thèse ouvrent un champ d’investigation innovant pour l’identification de nouvelles cibles de sélection variétale pour l’amélioration de la valeur technologique et de la qualité nutritionnelle du blé. Ils devraient ainsi permettre de mieux maîtriser la composition en protéines de réserve et ainsi produire des blés adaptés à des utilisations ciblées ou carencé en certaines fractions protéiques impliquées dans des phénomènes d’allergénicité et d’intolérance du gluten, ce dans un contexte d’agriculture durable et plus économe en intrants
Grain storage protein content and composition are the main determinants of bread wheat (Triticum aestivum L.) end-use value. Scaling laws governing grain protein composition according to grain nitrogen and sulfur content could be the outcome of a finely tuned regulation network. Although it was demonstrated that the main regulation of grain storage proteins accumulation occurs at the transcriptomic level in cereals, knowledge of the underlying molecular mechanisms is elusive. Moreover, the effects of nitrogen and sulfur on these mechanisms are unknown. The issue of skyrocketing data generation in research projects is addressed by developing high-throughput bioinformatics approaches. Extracting knowledge on from such massive amounts of data is therefore an important challenge. The work presented herein aims at elucidating regulatory networks involved in grain storage protein synthesis and their response to nitrogen and sulfur supply using a rule discovery approach. This approach was extended, implemented in the form of a web-oriented platform dedicated to the inference and analysis of regulatory networks from qualitative and quantitative –omics data. This platform allowed us to define different semantics in a comprehensive framework; each semantic having its own biological meaning, thus providing us with global informative networks. Spatiotemporal specificity of transcription factors expression was observed and particular attention was paid to their relationship with grain storage proteins in the inferred networks. The work initiated here opens up a field of innovative investigation to identify new targets for plant breeding and for an improved end-use value and nutritional quality of wheat in the context of inputs limitation. Further analyses should enhance the understanding of the control of grain protein composition and allow providing wheat adapted to specific uses or deficient in protein fractions responsible for gluten allergenicity and intolerance

APA, Harvard, Vancouver, ISO, and other styles

49

Oliveira, Cleoneide Maria do Nascimento. "Qualidade físico-química de sementes de milho tratadas com moringa oleifera lam. durante o armazenamento." Universidade Católica de Pernambuco, 2017. http://tede2.unicap.br:8080/handle/tede/1023.

Full text

Abstract:

Submitted by Biblioteca Central (biblioteca@unicap.br) on 2018-07-31T14:46:11Z No. of bitstreams: 2 cleoneide_maria_nascimento_oliveira.pdf: 1019585 bytes, checksum: bddadf02f4c656ca1807ab68d3a5d526 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2018-07-31T14:46:11Z (GMT). No. of bitstreams: 2 cleoneide_maria_nascimento_oliveira.pdf: 1019585 bytes, checksum: bddadf02f4c656ca1807ab68d3a5d526 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-07-17
Brazil is a country whose great potential for grain production has not yet been fully exploited. Corn is the most widespread and cultivated crop because it adapts to the most different ecosystems. Along with the effort to increase productivity, it is necessary to improve the harvesting process and the grain storage conditions. However, prolonged storage can only be achieved when harvesting, cleaning, drying and insect control practices are adopted correctly. The use of products applied through seeds, especially when stored, is a routine practice for the corn crop; However, growing concern about the environment and safety during the seed handling process has increased the demand for application technologies that allow risk reduction without compromising seed quality.Thus, the objective was to evaluate the physiological quality of maize seeds submitted to treatments, with five replicates, with doses equivalent to zero; 0.5; 1; 2 and 4 grams of the Moringa oleifera Lam. seed powder for each 10 grains of corn, with contact time corresponding to zero, 2, 4, 6 and 24 hours, 30 days and 6 months. The determinations were: germination test, moisture, volumetric weight, weight of 1000 grains, ash, acidity index and fungi. The results obtained show that the physiological quality of the corn seeds with the application of Moringa oleifera Lam. on maize seeds is technically feasible and can be stored for up six months without compromising their physiological quality.
O Brasil é um país cujo grande potencial de produção de grãos ainda não foi plenamente explorado. O milho é a cultura mais amplamente difundida e cultivada, pois se adapta aos mais diferentes ecossistemas. Junto com o esforço para o aumento da produtividade, necessariamente há que se aprimorar o processo de colheita e as condições de armazenagem de grãos. Entretanto, o armazenamento prolongado só pode ser realizado quando se adotam corretamente as práticas de colheita, limpeza, secagem e combate a insetos. O uso de produtos aplicados via sementes, principalmente quando armazenados, é uma prática rotineira para a cultura do milho; no entanto, a crescente preocupação com o ambiente e com a segurança durante o processo de manipulação dessas sementes tem aumentado a demanda por tecnologias de aplicação que permitam a redução dos riscos, sem que a qualidade das sementes seja comprometida. Assim, objetivou-se avaliar a qualidade físico-química de sementes de milho submetidas a tratamentos, com cinco repetições, com doses equivalentes a zero; 0,5; 1; 2 e 4 gramas do pó da semente da Moringa oleifera Lam. para cada 10 grãos de milho, com tempo de contato correspondente a zero, 2, 4, 6 e 24 horas, 30 dias e 6 meses. As determinações realizadas foram: teste de germinação, umidade, peso volumétrico, peso de 1000 grãos, cinzas e índice de acidez. Através dos resultados obtidos conclui-se que a qualidade das sementes de milho com a aplicação de Moringa oleifera Lam. é tecnicamente viável, podendo ser armazenadas por até seis meses, sem que haja comprometimento de sua qualidade fisiológica.

APA, Harvard, Vancouver, ISO, and other styles

50

Ferrasa, Marcelo 1970. "Sistema de monitoramento de temperatura e umidade em silos graneleiros via rádio /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/101702.

Full text

Abstract:

Resumo: O uso das Tecnologias da Informação e Comunicação tem crescido nas mais variadas atividades agrícolas. Como conseqüência, vem revolucionando a forma de pensar e agir do produtor que almeja se estabelecer em um mercado cada vez mais competitivo. Entretanto, o alto custo de aquisição e manutenção dessas tecnologias é um fator que pode inibir sua disseminação e aceitação, principalmente a um grande número de pequenos produtores de grãos. Diante desse cenário, há uma necessidade de soluções inovadoras adequadas a esse universo de produtores. Partindo-se dessa premissa, este trabalho apresenta o desenvolvimento de um protótipo de baixo custo para o monitoramento de temperatura e umidade de grãos armazenados em silos, utilizando uma tecnologia de comunicação sem fio por radiofreqüência. Para tanto, foram analisadas as implicações econômicas de custo/benefício do emprego inovador da transmissão sem fio no processo de termometria de grãos. O protótipo foi composto por duas unidades eletrônicas, uma de aquisição e outra de recepção de dados, além de um programa computacional que ofereceu ao produtor informações mais precisas para o controle da aeração. Por meio de testes realizados quanto à estabilidade, integridade e confiabilidade da transmissão de dados via rádio, utilizando componentes eletrônicos de baixo custo, pode-se considerar o sistema desenvolvido potencialmente viável. Este apresentou o diferencial da comunicação sem fio via rádio no processo de termometria de grãos, proporcionando mobilidade, minimizando custos com cabeamento, manutenção e oferecendo facilidades para sua expansão; também adequou-se ao monitoramento de temperatura eumidade de grãos em silos; e mostrou-se com viabilidade operacional, além do baixo custo de desenvolvimento quando comparado a produtos similares encontrados no mercado brasileiro.
Abstract: The use of Information and Communication Technology has grown in most agricultural activities. As a consequence, it has changed the way of thinking and acting of the farmer who wants to establish in a more and more competitive market. However, the high costs of acquisition and maintenance of those technologies may be a factor which can inhibit its spread and acceptance, mainly to a large number of small grain Brazilian farmers. In this context, there is a need for innovative solution which are proper for this universe of farmers. Starting from this premise, this paper presents the development of a low cost prototype to the monitoring process of temperature and humidity values of grains stored in silos, using communication based on wireless technology by radio frequency. Therefore, the economic implications of cost/benefit ratio of innovative application of wireless transmission in the process of thermometry of grains were analysed. The prototype was made of two electronic units, one of acquisition and another one of data reception, as well as a computational software, which offered the farmer more precise information for the control of aeration. By means of stability, integrity and reliability tests of data transmission via radio, using low cost electronic components, the development system can be considered as potentially viable. It presented the difference regarding the wireless communication via radio in the process of grains thermometry, providing mobility, reducing cabling costs and maintenance, and also offering an easy system expansion; it was also appropriate to temperature and humidity monitoring in grain silos; and revealed operational viability, besides 4 the low cost development when compared to similar products available in the Brazilian market.
Orientador: Marco Antonio Martin Biaggioni
Coorientador: Ariangelo Hauer Dias
Banca: Marcelo Giovaneti Canteri
Banca: Ivo Mario Mathias
Banca: Célia Regina Lopes Zimback
Banca: Kléber Pereira Lanças
Doutor

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Grain storage'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles