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11	Maîtrise de l’azote en système irrigué : application au contexte méditerranéen / Nitrogen control in unsaturated agricultural soils under irrigated systems : application to Mediteranean context Barakat, Mohammad 12 May 2017 (has links) La maîtrise du transfert de nitrates sous les systèmes irrigués est un objectif primordial dans l’agriculture moderne. Celle-ci exige la recherche, surtout en plein champ, de conduire une stratégie optimale de fertigation. Dans ce but, un protocole expérimental sur une parcelle de 2 ha a été mis en oeuvre pour analyser le devenir de l’’azote sous différents scénarios d’irrigation et de fertilisation d’une culture de maïs. Dans l’articulation de ce travail, et pour pouvoir étudier la dynamique de l’azote en systèmes irrigués, nous avons tout d’abord réussi à définir et clarifier la relation ambigüe entre la méthode d’irrigation (irrigation gravitaire, par aspersion ASP, en goutte à goutte de surface GGS ou enterré GGE) et les différentes transformations de l’azote (Fixation, Minéralisation, Immobilisation, Nitrification, Dénitrification et Volatilisation). Cette relation, peu claire et non traitée dans d’autres études similaires, a été étudiée en mettant l’accent sur l’effet de certains facteurs, comme par exemple, l’humidité de sol et sa température, sur l’activité microbienne et donc sur les différentes transformations de l’azote (comme la minéralisation) et ce en mettant en avant la relation directe ou indirecte avec les méthodes d’irrigation. Une différence significative a été observée pour la minéralisation in situ entre les traitements sans aucun apport d’engrais menés sous les deux méthodes d’irrigation GGE et ASP. Une méthode manuelle d’analyse a été ensuite mise au point et validée pour déterminer la concentration en azote dans les échantillons de sol prélevés dans le cadre de ce travail. Cette méthode peu onéreuse pourrait être profitable aux agriculteurs. Les données issues de l’ensemble des traitements ont été utilisées pour modéliser les flux hydriques et azotés à l’aide de modèle HYDRUS-2D pour les systèmes par aspersion et en goutte à goutte enterré. L’analyse de sensibilité aux paramètres liés au transfert de nitrates du modèle de transfert a permis d’estimer la dynamique azotée pour d’autres contextes hydro-pédo-climatiques plus complexes. En conclusion, la présente thèse a permis d’améliorer la connaissance du fonctionnement de la fertigation en irrigation goutte à goutte enterré par comparaison avec l’aspersion, en milieu méditerranéen, en vue d’une diminution des entrants agrochimiques dans un contexte d’économie de la ressource en eau. / The main goal in modern agriculture is the control of nitrogen fluxes in agricultural soils under the irrigation techniques. This objective requires a lot of research, especially in the field, to escort an optimal strategy of fertigation. For this purpose, an experimental protocol has been applied to follow the soil nitrogen fate for various irrigation and fertilization scenarios, during two intensive field campaigns in maize plots. In the articulation of our work, and to be able to examine the nitrogen dynamics in unsaturated agricultural soils under irrigated systems, we succeeded firstly to determine and clarify the ambiguous relation between the irrigation techniques (flood irrigation, sprinkler irrigation, surface and subsurface drip irrigation) and the different nitrogen transformations (Fixation, Mineralization, Immobilization, Nitrification, Denitrification and Volatilization) in agricultural contexts. This relationship, which is unclear and untreated in other similar studies, has been reviewed by studying the impact of certain factors, such as soil moisture and soil temperature under different irrigation techniques, on microbial soil activity and therefore on the nitrogen transformations (such as mineralization). A significant difference of mineralization was observed in maize plots with no fertilizer application treatment between sprinkler irrigation and subsurface drip irrigation. The experimental data collected have been used to analyze the water and nitrogen fluxes for various initial conditions and fertilisation strategies under sprinkler and subsurface drip irrigation by using the HYDRUS-2D model. Analyzing the sensitivity of nitrogen fluxes parameters using HYDRUS-2D allowed to estimate the nitrogen dynamics under more complex agro-pedoclimatic contexts. In conclusion, the present study allowed to improve the fertilization knowledge under both the sprinkler and subsurface drip irrigation in a Mediterranean environment. Irrigation par aspersion Irrigation goutte à goutte enterré Maïs Transferts eau-nitrate Modélisation numérique HYDRUS-2D Sprinkler irrigation Subsurface drip irrigation Corn Water and nitrates flux Numerical simulation HYDRUS-2D
12	Técnica experimental para quantificar a eficiência de distribuidores de líquidos industriais do tipo tubos perfurados paralelos. / Liquid aspersion effuciency quantification experiment: application in ladder type distributors. Moraes, Marlene Silva de 07 July 2008 (has links) O presente texto descreve um método experimental simples para comparar a eficiência de distribuidores de líquido empregados nas indústrias de tratamento de minérios em lavadores, classificadores e moinhos e nas indústrias de processos químicos. A técnica consiste basicamente em analisar a dispersão pelo desvio padrão da massa do líquido coletado em tubos verticais dispostos em arranjo quadrático colocados abaixo do distribuidor. Como exemplo de aplicação, empregouse para a coleta da massa de líquido uma unidade piloto, montada no Laboratório de Engenharia Química da Universidade Santa Cecília em Santos, com um banco de 21 tubos verticais de 52 mm de diâmetro interno e 800 mm de comprimento. Uma manta acrílica que não dispersa o líquido com 50 mm de espessura foi fixada entre o distribuidor e o banco de tubos para evitar respingos. Foram realizados ensaios com nove distribuidores do tipo espinha de peixe de 4 tubos paralelos cada, para uma coluna piloto com 400 mm de diâmetro. A literatura é discordante no que concerne aos parâmetros de projeto e eficiência destes distribuidores. Variaram-se o número (n) de orifícios (95, 127 e 159 furos/m2, 12, 16 e 20 furos por distribuidor) o diâmetro (d) dos orifícios (2, 3 e 4 mm) e as vazões de entrada indicadas por rotâmetro nos distribuidores (q) de 1,2; 1,4 e 1,6 m3/h. A melhor eficiência de espalhamento pelo menor desvio padrão (0,302) foi obtida com n de 159 furos/m2, d de 2 mm e q de 1,4 m3/h indicando as limitações dos parâmetros de projeto da literatura. A pressão (p), na entrada do distribuidor para esta condição, foi de apenas 0,51 kgf/cm2. A relação adimensional entre a área da seção do tubo de alimentação e a somatória da área dos furos foi de 5,81, a vazão volumétrica total por unidade de área da seção da coluna para esta melhor condição foi de 11,32 m3/(h.m2) e a velocidade média (v) em cada orifício foi de 6,31 m/s. Portanto, o método proposto permite comparar e quantificar a eficiência de distribuidores além de demonstrar a não validade de alguns parâmetros de projeto recomendados pela literatura. / The current text describes a simple experimental method in order to compare the efficiency of the liquid distributors applied at the ore treatment industries in washers, classifiers and mills as well as at the chemical processing industries. The technique basically consist of analyzing the dispersion through the standard deviation of the liquid mass which was collected in vertical pipes placed in a square way under the distributor. As an example of us usage, it has been applied a pilot scale for collecting the liquid mass, installed at the Santa Cecília Universitys Chemical Engineering Laboratory in Santos, with a setting of 21 vertical tubes measuring 52 mm in internal diameter and 800 mm in length. A 50 mm thick acrylic blanket was fixed between the distributor and the pipe setting in order to avoid splashes. Some experiments have been made with a ladder-tipe distributors containing 4 parallel tubes each, for a pilot column of 400 mm in diameter. The literature shows disagreement regarding the characteristics of the project and the efficiency of the distributors. The number of holes has varied (n) 95, 127 and 159 holes/m2; 12, 16 and 20 holes for distributor, the diameter of the holes (d) 2, 3 and 4 mm and the flow of entrance in the distributors (q) of 1,2; 1,4 and 1,6 m3/h. The best efficiency of splashing of the lowest deviation pattern (0,302) was achieved with n of 159 holes/m2, d of 2 mm and q of 1,4 m3/h showing the limitation of characteristics of the project literature. The pressure (p), for this condition in the distributor entrance, was only 0,51 kgf/cm2. The measuring relation between the area of the section of the feeding pipe and the addition of the area of the roles was 5,81, the total volume of the out flow for unit of the area of the column section for this better condition was 11,32 m3/(h m2) and the average speed (v), in each hole was 6,31 m/s. Finally, the indicated method permits the comparison and quantification of the efficiency of the distributors, besides showing that some of the project concepts are not valid and the literature does not recommend them. Dust dry cleaner Fisch spine Gas washer Ladder pipe distributors Liquid aspersion device Liquid distributor Log washer Ore classifiers Ore washer Processamento mineral Qualidade do processo Washer distributor Wet mills Wet scrubber
13	Técnica experimental para quantificar a eficiência de distribuidores de líquidos industriais do tipo tubos perfurados paralelos. / Liquid aspersion effuciency quantification experiment: application in ladder type distributors. Marlene Silva de Moraes 07 July 2008 (has links) O presente texto descreve um método experimental simples para comparar a eficiência de distribuidores de líquido empregados nas indústrias de tratamento de minérios em lavadores, classificadores e moinhos e nas indústrias de processos químicos. A técnica consiste basicamente em analisar a dispersão pelo desvio padrão da massa do líquido coletado em tubos verticais dispostos em arranjo quadrático colocados abaixo do distribuidor. Como exemplo de aplicação, empregouse para a coleta da massa de líquido uma unidade piloto, montada no Laboratório de Engenharia Química da Universidade Santa Cecília em Santos, com um banco de 21 tubos verticais de 52 mm de diâmetro interno e 800 mm de comprimento. Uma manta acrílica que não dispersa o líquido com 50 mm de espessura foi fixada entre o distribuidor e o banco de tubos para evitar respingos. Foram realizados ensaios com nove distribuidores do tipo espinha de peixe de 4 tubos paralelos cada, para uma coluna piloto com 400 mm de diâmetro. A literatura é discordante no que concerne aos parâmetros de projeto e eficiência destes distribuidores. Variaram-se o número (n) de orifícios (95, 127 e 159 furos/m2, 12, 16 e 20 furos por distribuidor) o diâmetro (d) dos orifícios (2, 3 e 4 mm) e as vazões de entrada indicadas por rotâmetro nos distribuidores (q) de 1,2; 1,4 e 1,6 m3/h. A melhor eficiência de espalhamento pelo menor desvio padrão (0,302) foi obtida com n de 159 furos/m2, d de 2 mm e q de 1,4 m3/h indicando as limitações dos parâmetros de projeto da literatura. A pressão (p), na entrada do distribuidor para esta condição, foi de apenas 0,51 kgf/cm2. A relação adimensional entre a área da seção do tubo de alimentação e a somatória da área dos furos foi de 5,81, a vazão volumétrica total por unidade de área da seção da coluna para esta melhor condição foi de 11,32 m3/(h.m2) e a velocidade média (v) em cada orifício foi de 6,31 m/s. Portanto, o método proposto permite comparar e quantificar a eficiência de distribuidores além de demonstrar a não validade de alguns parâmetros de projeto recomendados pela literatura. / The current text describes a simple experimental method in order to compare the efficiency of the liquid distributors applied at the ore treatment industries in washers, classifiers and mills as well as at the chemical processing industries. The technique basically consist of analyzing the dispersion through the standard deviation of the liquid mass which was collected in vertical pipes placed in a square way under the distributor. As an example of us usage, it has been applied a pilot scale for collecting the liquid mass, installed at the Santa Cecília Universitys Chemical Engineering Laboratory in Santos, with a setting of 21 vertical tubes measuring 52 mm in internal diameter and 800 mm in length. A 50 mm thick acrylic blanket was fixed between the distributor and the pipe setting in order to avoid splashes. Some experiments have been made with a ladder-tipe distributors containing 4 parallel tubes each, for a pilot column of 400 mm in diameter. The literature shows disagreement regarding the characteristics of the project and the efficiency of the distributors. The number of holes has varied (n) 95, 127 and 159 holes/m2; 12, 16 and 20 holes for distributor, the diameter of the holes (d) 2, 3 and 4 mm and the flow of entrance in the distributors (q) of 1,2; 1,4 and 1,6 m3/h. The best efficiency of splashing of the lowest deviation pattern (0,302) was achieved with n of 159 holes/m2, d of 2 mm and q of 1,4 m3/h showing the limitation of characteristics of the project literature. The pressure (p), for this condition in the distributor entrance, was only 0,51 kgf/cm2. The measuring relation between the area of the section of the feeding pipe and the addition of the area of the roles was 5,81, the total volume of the out flow for unit of the area of the column section for this better condition was 11,32 m3/(h m2) and the average speed (v), in each hole was 6,31 m/s. Finally, the indicated method permits the comparison and quantification of the efficiency of the distributors, besides showing that some of the project concepts are not valid and the literature does not recommend them. Processamento mineral Qualidade do processo Dust dry cleaner Fisch spine Gas washer Ladder pipe distributors Liquid aspersion device Liquid distributor Log washer Ore classifiers Ore washer Washer distributor Wet mills Wet scrubber
14	Fauxtopia Kampf, Raymond William 01 January 2004 (has links) To all who come to this fictitious place:Welcome.Fauxtopia is your land. Here, age relives distorted memories of the past, and here, youth may savor the challenge of trying to understand the present. Fauxtopia is made up of the ideals, the dreams and the fuzzy facts which have re-created reality... with the hope that it will be a source of edutainment for all the world.Ray KampfFauxtopia DedicationApril 1st, 2004 swindle subterfuge story stooge stereotype stratagem spurious spiel soft-soap snow job simulated aspersion adventure artificial anecdote allegory advertising assumptions belie bluff bogus brainwash calumniation canard cheat chronicle cliche cliffhanger con man conceal counterfeit crooked deal deceit deception disguise dishonest distort double cross ersatz evangelism exaggerate fabrication facade fake falsehood fantasy fib fiction flim flam fool folktale forgery frame up fraudulence fudge gag grifter guile guise history hoax hokey hype hyperbole knavery legend likeness make believe malign mask memoir misrepresentation mockery myth parable parody performance perjury phony placebo player ploy potboiler prevarication propaganda publicity puppet put-on quasi record reproduction romance routine ruse saga scam shtick semblance sequel show serial synthetic tall story trick unnatural untruth veneer verisimilitude white lie whopper Disney politics hyper reality theme park entertainment Art and Design Arts and Humanities

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