176,752 research outputs found
Effect of gaseous ozone treatment on the aroma and clove rot by Fusarium proliferatum during garlic postharvest storage
No full textIt is known that garlic bulbs preserved with traditional methods undergo considerable losses, ranging from 25 to 40%. A frequent cause of these losses is associated with the development of pathogenic fungi, such as those of the genus Fusarium. The effect of ozone on post-harvest garlic bulbs was evaluated. Garlic cloves inoculated with Fusarium proliferatum F21 and F22 strains, were exposed to a continuous gaseous ozone flow (2.14 μg m−3), during 4 days, 20 h a day. After ozone-treatment, the garlic samples were moved at 22 °C to mimic retail conditions (shelf life). The changes in several quality parameters such as fungal decay and aroma were evaluated on garlic samples, as whole bulbs, cloves with and without tunic, through a sensorial descriptive test, SPME analysis in GC/MS and microbiological approaches. The data collected showed that ozone treatment did not affect the aromatic profile of garlic. A significant detrimental effect of ozone treatment on garlic decay was observed. Our results encourage the use of gaseous ozone treatment for containing garlic fungal decay during its storage
Innovative Uranium-free Fuels for Weapons Plutonium Disposition in Current LWRs
No full textAbout 100 MT of excess plutonium are going to be originated from warheads dismantling under the START II agreements (50 MT by each side US and former Soviet Union), and another about 200 MT are already stockpiled from commercial spent fuel reprocessing. The civilian or reactor grade plutonium (RG-Pu), amounted at about 1000 MT total world inventory at the end of 1995, and is forecasted to attain some 1500 MT by the year 2000. Therefore, there is a pressing need in finding novel and ever more safe methods to deal with all kind of excess plutonium in the aim of rendering it ultimately unusable for proliferation purposes.As to weapons Pu, one leading option (US and Russia) is to burn it in LWRs after having converted it to MOX fuel. However, among the possible types of fuel which can be envisaged to burn plutonium in LWRs, innovative U-free fuels such as inert matrix and thoria fuel are novel conceptd that find justification since, especially for weapons Pu transmutation, the precisely required fuel is not immediately available and even for the LWR weapon-MOX, processes and facilities have to be set-up before reaching the operational stage.From calculations related to inert matrix U-free fuel in a commercial PWR, in a once-through cycle mode, emerges that IMF has the highest Pu burning capability: >93% of fissile plutonium and 74/85% of total WG-Pu and RG-Pu, is burnt at end of fuel life. The fabrication tests on simulate fuel demonstrate that the nuclear-grade specifications can be met and a very limited solubility under the current fuel reprocessing techniques, coupled to the quality-poor residual Pu in the spent fuel, will make the proposed fuel a potentially strong anti-proliferation product
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
Occurrence of Phytophthora cinnamomi in cork oak forests in Italy
No full textAn increasing decline and mortality of cork oak trees have been recently observed in central Italy and Sardinia Island. Following surveys conducted in three declining cork oak forests, a Phytophthora species was consistently isolated from soil samples collected from trees displaying different level of decline. Based on morphological features, growth rates at different temperatures and analysis of DNA sequences of the ITS region, all isolates were identified as Phytophthora cinnamomi Rands. This pathogen caused large brownish lesions on inoculated freshly cut branches of cork oak. It was re-isolated from all infected tissues. These findings represent the first report of P.cinnamomi on cork oak trees in Italy
Vesical and vaginal recurrent endometriosis in postmenopause following estrogen replacement therapy [3]
No full text[No abstract available
Intern experience at CH���M Hill, Inc.: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical referencesA review of the author's internship experience with CH���M HILL, Inc.
during the period September 1975 through May 1976 is presented. During this nine month
internship the author worked as an Engineer II in the Industrial Processes discipline of this
large consulting engineering firm... The author's prime responsibility was as one of three
lead design engineers on the design of a large wastewater treatment facility for a pulp mill
in Hoquiam, Washington owned by ITT Rayonier Inc. The work generally consisted of the design
of individual treatment units and associated piping and pumping. The purpose of the project
was to provide wastewater treatment capabilities that would satisfy the effluent limitations
(standards) imposed upon the mill by the State of Washington Department of Ecology and the
U.S. Environmental Protection Agency. The author's assignment also entailed necessary
interaction with the project manager and other CH���M HILL design engineers and support staff
members, the client's representatives, and representatives of two other consulting engineering
firms working on the project. Thus, the internship position at CH���M HILL provided considerable
experience coordinating the author's work with the work of other engineers, guiding the design
and administrative efforts of a support staff, and interacting regularly with the client and
other consulting firms. This broad exposure to a variety of engineering and organizational
problems provided a valuable educational experience
Plutonia-Thoria Fuel Cycle as Starting Solution for a Wider Thorium Use
No full textThis paper is focused on a description of thoria fuel option. Our opinion is that this option, beyond being a valuable way to exploit the energy content of plutonium without further breeding it, may be a starting point for introducing an Uranium-Thorium fuel cycle, based on a different strategic context with respect to past proposals. The option is based on the adoption of current or advanced PWRs, the latter characterised by a reduced fuel power density, always adopting conventional fuel rods and assemblies. A three-batches full core loading scheme is assumed. The thoria-plutonia composition is determined by the constraints to obtain at Beginning Of Life (BOL) a non positive void coefficient, and to reach a burnup as high as possible. Different fuel compositions and pellet radius are considered. The plutonium content is in the range of 4.5 ̃15%, mainly depending on the plutonium quality, namely Weapon Grade (WG) or Reactor Grade (RG). The results are in terms of dynamic coefficients, life duration, plutonium consumption and final isotopic compositions. These fuels show the capability to destroy about 40 ̃60% of total plutonium for RG, while this figure rises to 65 ̃70% for WG. These values are well above those obtained by MOX option
Feasibility of Advanced Fuel or Target Fabrication
No full textProject Report EUR 19128EN, Evaluation of Possible Partitioning and Transmutation Strategies and of Means for Implementing Them, Part D, pp. 1-3
Response of endophytic Biscogniauxia mediterranea to variation in leaf water potential of Quercus cerris
No full textEndophytic behaviour of Biscogniauxia mediterranea, the causal agent of charcoal disease of oak, was studied over two growing seasons on Quercus cerris in a forest in central Italy. Isolation of the fungus from asymptomatic tissues varied with tissue type, period of sampling and year. Presence of the fungus in asymptomatic plants was significantly higher in fall, compared with that in spring and summer. However, a significant effect of tissue water content on the presence of B. mediterranea was recognized. The results suggest that proliferation of B. mediterranea is favoured during the endophytic phase by a decrease in host water potential.Fil: Vannini, A.. Università degli Studi della Tuscia; ItaliaFil: Lucero, Gabriela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Anselmi, N.. Università degli Studi della Tuscia; ItaliaFil: Vettraino, A. M.. Università degli Studi della Tuscia; Itali
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