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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Zoneamento ecológico-econômico versus planos de recursos hídricos, com aplicação na região norte do estado do Tocantins

Magalhães, Danielle Soares January 2010 (has links)
No Brasil, particularmente nas últimas décadas, um considerável número de instrumentos de políticas foram criados, para uma melhor gestão dos recursos naturais do país. Dentre os instrumentos, destacam-se o Zoneamento Ecológico-Econômico e os Planos de Recursos Hídricos, ambos de políticas ambientais distintas, porém com objetivos, em partes, semelhantes, ao proporem, em seu escopo, a criação de áreas sujeitas à restrição de uso para uma melhor gestão do território e dos recursos hídricos, respectivamente. Diante da problemática de dinamizar o planejamento ambiental, este trabalho tem como objetivo analisar a efetividade de ambos os instrumentos de políticas ao considerar o efeito das proposições dos usos do solo sobre a disponibilidade quantitativa dos recursos hídricos de uma bacia. Para testar a efetividade dos instrumentos será desenvolvido um caso de estudo na região norte do Estado do Tocantins, especificamente nas bacias dos rios Lontra e Corda, inseridas no sistema hidrográfico do rio Araguaia. As bacias foram selecionadas por possuírem elaborados um plano de Zoneamento Ecológico-Econômico e um Plano de Bacia Hidrográfica, a serem implantados em uma mesma área. Os rios das bacias em apreço apresentam uma considerável interação com os recursos hídricos subterrâneos, necessitando de uma gestão integrada das componentes hídricas. Aplicaram-se filtros digitais recursivos para separação do escoamento de base do escoamento total de hidrogramas das séries históricas de duas estações fluviométricas (2820000 e 28240000 – Hidroweb/ANA) e observou-se que 80 e 76% das vazões dos rios são mantidas pelos aqüíferos da região. Ao considerarem que os aqüíferos são importantes para manutenção da vazão dos rios e que os mesmos estão localizados em áreas propicias a usos do solo, este trabalho buscou localizar, na área em estudo, as áreas potenciais de armazenamento de água subterrânea, possivelmente áreas de recarga de aqüíferos (CHIARANDA, 2002), a fim de observar as proposições de ambos os instrumentos para as referidas áreas. Com o auxílio de técnicas de ponderação, análise e cruzamento de mapas temáticos em ambiente de Sistema de Informações Geográficas (SIG), foi possível observar que grande parte da área das bacias dos rios Lontra e Corda estão inseridas em classes de muito alta a alta capacidade de armazenamento de água subterrânea. Como resultado da análise da efetividade dos instrumentos, algumas divergências foram observadas quanto à proposição das zonas, que no ato da implementação dos instrumentos poderá acarretar prejuízos econômicos e/ou ambiental para a região, a exemplo, a indicação para uma mesma localidade de criação de áreas restritas ao uso e de ocupação por atividades humanas. Ao realizar o cruzamento das zonas dos ZEE’s sobre as áreas potenciais de armazenamento de água subterrânea, observou-se que ambos os instrumentos propõe áreas de ocupação humana, sobre as áreas de maior potencial de armazenamento de água subterrânea. Não sendo evidenciada nenhuma proposta quanto aos cuidados específicos em relação à preservação destas áreas, não reconhecendo a interação existente entre as águas subterrâneas e superficiais e sua necessidade de gestão integrada para uma melhor qualidade ambiental da região. / In Brazil, particularly in recent decades, a considerable number of policy instruments were created for better management of natural resources of the country. Among the instruments stand out from the Ecological and Economic Zoning and Plans of Water Resources, both of different environmental policies, but with goals, in part, similar to propose in its scope, the creation of areas subject to use restrictions for better land management and water resources, respectively. Regarding the problem of dynamic environmental planning, this work is to analyze the effectiveness of both policy instruments to consider the effect of the proposals of land use on the availability of water resources in a bowl. To test the effectiveness of both instruments will be developed a case study in the northern state of Tocantins, specifically in the basins of the rivers Otter and rope, inserted in the hydrographic system of the Araguaia River. The basins were selected because they have drawn up a plan of Ecological-Economic Zoning Plan and a Watershed, both to be deployed in the same area. The rivers in this basin have a considerable interaction with the groundwater resources, requiring an integrated component of water. Applied to recursive digital filters for separating the base flow of total flow hydrographs of historical series of two gauged stations (2820000 and 28240000 - Hidroweb / ANA) and observed that 80 and 76% of the flows of rivers are maintained by aquifers the region. In considering that the aquifers are important for maintaining river flows and that they are located in areas conducive to land use, this study tried to find, in the study area, the potential areas of water storage underground, possibly recharge areas aquifer (CHIARANDA 2002), in order to observe the propositions of both instruments for those areas. With the help of techniques of measurement, analysis and cross-thematic maps in an environment of geographic information system (GIS), it was observed that much of the area of the basins of rivers Otter and rope are placed in classes for very high discharge capacity storage of groundwater. Based on the analysis of the effectiveness of the instruments, some differences were observed concerning a proposed areas, which at the time of implementation of both instruments may cause economic losses and / or environmental in the region, such as the indication for the same location establishment of restricted areas to use and occupancy by human activities. When performing the crossroad of the exclusive economic areas of potential water storage underground, it was observed that both instruments proposed areas of human occupation on the areas of greatest potential for water storage underground. Not being shown any proposal regarding the specific care for the preservation of these areas, not recognizing the interaction between groundwater and surface water and their need for integrated management for better environmental quality in the region.
32

Zoneamento ecológico-econômico versus planos de recursos hídricos, com aplicação na região norte do estado do Tocantins

Magalhães, Danielle Soares January 2010 (has links)
No Brasil, particularmente nas últimas décadas, um considerável número de instrumentos de políticas foram criados, para uma melhor gestão dos recursos naturais do país. Dentre os instrumentos, destacam-se o Zoneamento Ecológico-Econômico e os Planos de Recursos Hídricos, ambos de políticas ambientais distintas, porém com objetivos, em partes, semelhantes, ao proporem, em seu escopo, a criação de áreas sujeitas à restrição de uso para uma melhor gestão do território e dos recursos hídricos, respectivamente. Diante da problemática de dinamizar o planejamento ambiental, este trabalho tem como objetivo analisar a efetividade de ambos os instrumentos de políticas ao considerar o efeito das proposições dos usos do solo sobre a disponibilidade quantitativa dos recursos hídricos de uma bacia. Para testar a efetividade dos instrumentos será desenvolvido um caso de estudo na região norte do Estado do Tocantins, especificamente nas bacias dos rios Lontra e Corda, inseridas no sistema hidrográfico do rio Araguaia. As bacias foram selecionadas por possuírem elaborados um plano de Zoneamento Ecológico-Econômico e um Plano de Bacia Hidrográfica, a serem implantados em uma mesma área. Os rios das bacias em apreço apresentam uma considerável interação com os recursos hídricos subterrâneos, necessitando de uma gestão integrada das componentes hídricas. Aplicaram-se filtros digitais recursivos para separação do escoamento de base do escoamento total de hidrogramas das séries históricas de duas estações fluviométricas (2820000 e 28240000 – Hidroweb/ANA) e observou-se que 80 e 76% das vazões dos rios são mantidas pelos aqüíferos da região. Ao considerarem que os aqüíferos são importantes para manutenção da vazão dos rios e que os mesmos estão localizados em áreas propicias a usos do solo, este trabalho buscou localizar, na área em estudo, as áreas potenciais de armazenamento de água subterrânea, possivelmente áreas de recarga de aqüíferos (CHIARANDA, 2002), a fim de observar as proposições de ambos os instrumentos para as referidas áreas. Com o auxílio de técnicas de ponderação, análise e cruzamento de mapas temáticos em ambiente de Sistema de Informações Geográficas (SIG), foi possível observar que grande parte da área das bacias dos rios Lontra e Corda estão inseridas em classes de muito alta a alta capacidade de armazenamento de água subterrânea. Como resultado da análise da efetividade dos instrumentos, algumas divergências foram observadas quanto à proposição das zonas, que no ato da implementação dos instrumentos poderá acarretar prejuízos econômicos e/ou ambiental para a região, a exemplo, a indicação para uma mesma localidade de criação de áreas restritas ao uso e de ocupação por atividades humanas. Ao realizar o cruzamento das zonas dos ZEE’s sobre as áreas potenciais de armazenamento de água subterrânea, observou-se que ambos os instrumentos propõe áreas de ocupação humana, sobre as áreas de maior potencial de armazenamento de água subterrânea. Não sendo evidenciada nenhuma proposta quanto aos cuidados específicos em relação à preservação destas áreas, não reconhecendo a interação existente entre as águas subterrâneas e superficiais e sua necessidade de gestão integrada para uma melhor qualidade ambiental da região. / In Brazil, particularly in recent decades, a considerable number of policy instruments were created for better management of natural resources of the country. Among the instruments stand out from the Ecological and Economic Zoning and Plans of Water Resources, both of different environmental policies, but with goals, in part, similar to propose in its scope, the creation of areas subject to use restrictions for better land management and water resources, respectively. Regarding the problem of dynamic environmental planning, this work is to analyze the effectiveness of both policy instruments to consider the effect of the proposals of land use on the availability of water resources in a bowl. To test the effectiveness of both instruments will be developed a case study in the northern state of Tocantins, specifically in the basins of the rivers Otter and rope, inserted in the hydrographic system of the Araguaia River. The basins were selected because they have drawn up a plan of Ecological-Economic Zoning Plan and a Watershed, both to be deployed in the same area. The rivers in this basin have a considerable interaction with the groundwater resources, requiring an integrated component of water. Applied to recursive digital filters for separating the base flow of total flow hydrographs of historical series of two gauged stations (2820000 and 28240000 - Hidroweb / ANA) and observed that 80 and 76% of the flows of rivers are maintained by aquifers the region. In considering that the aquifers are important for maintaining river flows and that they are located in areas conducive to land use, this study tried to find, in the study area, the potential areas of water storage underground, possibly recharge areas aquifer (CHIARANDA 2002), in order to observe the propositions of both instruments for those areas. With the help of techniques of measurement, analysis and cross-thematic maps in an environment of geographic information system (GIS), it was observed that much of the area of the basins of rivers Otter and rope are placed in classes for very high discharge capacity storage of groundwater. Based on the analysis of the effectiveness of the instruments, some differences were observed concerning a proposed areas, which at the time of implementation of both instruments may cause economic losses and / or environmental in the region, such as the indication for the same location establishment of restricted areas to use and occupancy by human activities. When performing the crossroad of the exclusive economic areas of potential water storage underground, it was observed that both instruments proposed areas of human occupation on the areas of greatest potential for water storage underground. Not being shown any proposal regarding the specific care for the preservation of these areas, not recognizing the interaction between groundwater and surface water and their need for integrated management for better environmental quality in the region.
33

Structure And Oxygen Storage Capacity Of Ce1-xMxO2-δ(M=Sn, Zr, Mn, Fe, Co, Ni, Cu, La, Y, Pd, Pt, Ru) : Experimental And Density Functional Theoritical Study

Gupta, Asha 07 1900 (has links) (PDF)
Ceria (CeO2) containing materials are the subject of numerous investigations recently owing to their broad range of applications in various fields. Ceria is one of the most important components of three-way catalysts (TWC). Two unique features are responsible for making CeO2 a promising material for use either as a support or as an active catalyst: (a) the Ce3+/Ce4+ redox couple, and (b) its ability to shift between CeO2 and CeO2–δ under oxidizing and reducing conditions retaining fluorite structure. Despite widespread applications, pure CeO2 has a serious problem of degradation in performance with time at elevated temperatures. CeO2 undergoes rapid sintering under high operating temperatures, which leads to loss of oxygen buffer capacity and deactivation of the catalyst. In addition, the amount of lattice oxygen taking part in the redox reactions is small (δ ~ 0.05), and therefore unsatisfactory for practical applications. Therefore further improvement of OSC of CeO2 has led to development of new CeO2-based oxygen storage materials. Modifications of CeO2 with isovalent or aliovalent ion (noble metal, rare-earth or transition metal) confer new properties to the catalysts, such as better resistance to sintering and high catalytic activity. The demand for ceria-based oxygen storage materials were accelerated in the 1970s with the introduction of strict automotives exhaust treatment worldwide to combat the obnoxious gases released in the atmosphere causing deterioration of air quality. Significant developments have occurred in this field leading to better understanding of the catalysts synthesis, structure and improved catalytic activity. The introductory chapter 1 is a compendium to provide an overview of the topic, examine the critical lacunae in the field and the proposal for future developments. In chapter 2 we present the studies on synthesis and catalytic properties of Ce1– xSnxO2 (x= 0.1–0.5) solid solution and its Pd substituted analogue. A brief description of the single step solution combustion synthesis, catalysts characterization techniques such as powder X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) are given. Design and fabrication of temperature programmed reduction by hydrogen (H2-TPR) system in this laboratory is given in details. The home-made temperature programmed catalytic reaction system with a quadrupole mass spectrometer and an on-line gas-chromatograph for gas analysis is described. For the synthesis of Ce1–xSnxO2 solid solution by a single-step solution combustion method we have used tin oxalate as precursor for Sn. The compounds were characterized by XRD, XPS and TEM. Oxygen storage capacity of the Ce1–xSnxO2 solid solution was measured by H2-TPR. The cubic fluorite structure remained intact up to 50% of Sn substitution in CeO2, and the compounds were stable up to 700 °C. Oxygen storage capacity of Ce1–xSnxO2 was found to be much higher than that of Ce1–xZrxO2 due to accessible Ce4+/Ce3+ and Sn4+/Sn2+ redox couples at temperatures between 200 to 400 °C. Pd2+ ions in Ce0.78Sn0.2Pd0.02O2-δare highly ionic, and the lattice oxygen of this catalyst is highly labile, leading to low temperature CO to CO2 conversion. The rate of CO oxidation was 2 μmolg–1s–1 at 50 °C. NO reduction by CO with 70% N2 selectivity was observed at ~200 °C and 100% N2 selectivity below 260 °C with 1000-5000 ppm NO. Pd2+ ion substituted Ce1–xSnxO2 catalyst can be used for low temperature exhaust applications due to the involvement of the Sn2+/Sn4+ redox couple along with Pd2+/Pd0 and Ce4+/Ce3+ couples. With the goal to understand the improved OSC for Ce1–xSnxO2 solid solution, we have investigated the structure and its relative stability based on first-principles density functional calculations. In chapter 3, we present our studies on the relative stability of Ce1–xSnxO2 solid solution in fluorite in comparison to rutile structure of the other end-member SnO2. Analysis of relative energies of fluorite and rutile phases of CeO2, SnO2, and Ce1–xSnxO2 indicates that fluorite structure is most stable for Ce1–xSnxO2 solid solution. An analysis of local structural distortions reflected in phonon dispersion show that SnO2 in fluorite structure is highly unstable while CeO2 in rutile structure is only weakly unstable. Thus, Sn in Ce1–xSnxO2-fluorite structure is associated with high local structural distortion whereas Ce in Ce1–xSnxO2-rutile structure, if formed, will show only marginal local distortion. Determination of M–O (M = Ce or Sn) bond lengths and analysis of Born effective charges for the optimized structure of Ce1–xSnxO2 show that local coordination of these cations changes from ideal eight-fold coordination expected of Ce4+ ion in fluorite lattice, leading to generation of long and short Ce–O and Sn–O bonds in the doped structure. Bond valence analyses for all ions show the presence of oxygen with bond valence ~1.84. These weakly bonded oxygen ions are relevant for enhanced oxygen storage/release properties observed in Ce1–xSnxO2 solid solution. In chapter 4, we present detailed structural analysis of Ce1–xSnxO2 and Ce1–x– ySnxPdyO2–δsolid solutions based on our DFT calculations supported with EXAFS studies. Both EXAFS analysis and DFT calculation reveal that in the solid solution Ce exhibits 4 + 4 coordination, Sn exhibits 4 + 2 + 2 coordination and Pd has 4 + 3 coordination. While the oxygen in the first four coordination with short M—O bonds are strongly held in the lattice, the oxygens in the second and higher coordinations with long M—O bonds are weakly bound, and they are the activated oxygen in the lattice. Bond valence analysis shows that oxygen with valencies as low as 1.65 are created by the Sn and Pd ion substitution. Another interesting observation is that H2-TPR experiment of Ce1–xSnxO2 shows a broad peak starting from 200 to 500 oC, while the same reduction is achieved in a single step at ~110 oC in presence Pd2+ ion. Substitution of Pd2+ ion thus facilitates synergistic reduction of the catalyst at lower temperature. We have shown that simultaneous reduction of the Ce4+ and Sn4+ ions by Pd0 is the synergistic interaction leading to high oxygen storage capacity at low temperature. In chapter 5, we present the effect of substituting aliovalent Fe3+ ion on OSC and catalytic activity of ceria. Ce0.9Fe0.1O2–δ and Ce0.89Fe0.1Pd0.01O2–δ solid solutions have been synthesized by solution combustion method, which show higher oxygen storage/release property compared to CeO2 and Ce0.8Zr0.2O2. Temperature programmed reduction and XPS study reveal that the presence of Pd ion in Ce0.9Fe0.1O2–δ facilitates complete reduction of Fe3+ to Fe2+ state and partial reduction of Ce4+ to Ce3+ state at temperatures as low as 105 oC compared to 400 oC for monometal-ionic Ce0.9Fe0.1O2–δ. Fe3+ ion is reduced to Fe2 and not to Fe0 due to favorable redox potential for Ce4 + Fe2൅ → Ce3 + Fe3 reaction. Using first-principles density functional theory calculation we determine M—O (M = Pd, Fe, Ce) bond lengths, and find that bond lengths vary from shorter (2.16 Å) to longer (2.9 Å) bond distances compared to mean Ce—O bond distance of 2.34 Åfor CeO2. Using these results in bond valence analysis, we show that oxygen with bond valences as low as –1.55 are created, leading to activation of lattice oxygen in the bimetal ionic catalyst. Temperatures of CO oxidation and NO reduction by CO/H2 are lower with the bimetal ionic Ce0.89Fe0.1Pd0.01O2–δ catalyst compared to monometal-ionic Ce0.9Fe0.1O2–δ and Ce0.99Pd0.01O2–δ catalysts. From XPS studies of Pd impregnated on CeO2 and Fe2O3 oxides, we show that the synergism leading to low temperature activation of lattice oxygen in bimetal-ionic catalyst Ce0.89Fe0.1Pd0.01O2–δ is due to low-temperature reduction of Pd2 to Pd0, followed by Pd0 + 2Fe3൅ → Pd2 +2Fe2, Pd0 + 2Ce4൅ → Pd2 + 2Ce3redox reaction. In chapter 6, we simulate the structure of Ce1–xMxO2–δ (M = transition metal, noble metal and rare–earth ions) for theoretical understanding of origin of OSC in these oxides and to draw a general criteria required to increase the OSC in ceria. The relationship between the OSC and structural changes induced by the dopant ion was investigated by H2-TPR and first-principles based density functional calculations. Transition metal and noble metal ions substitution in ceria greatly enhances the reducibility of Ce1–xMxO2–δ (M = Mn, Fe, Co, Ni, Cu, Pd, Pt, Ru), whereas rare–earth ions substituted Ce1–xAxO2–δ (A = La, Y) have very little effect in improving the OSC. Our simulated optimized structure shows deviation in cation–oxygen bond length from ideal bond length of 2.34 Å (for CeO2). For example, our calculation for Ce28Mn4O62 structure shows that Mn—O bonds are in 4+2 coordination with average bond lengths of 2.0 and 3.06 Å respectively. While the four short Mn–O bond lengths for the calculated structure spans the bond distance region of Mn2O3, and the other two Mn–O bonds are moved to longer distances. The dopant transition and noble metal ions also affects Ce coordination shell and results in the formation of longer Ce—O bonds as well. Thus longer cation-oxygen bond lengths for both dopant and host ions results in enhanced synergistic reduction of the solid solution. With Pd ion substitution in Ce1–xMxO2–δ (M = Mn Fe, Co, Ni, Cu) further enhancement in OSC is observed in H2–TPR. This effect is reflected in our calculations by the presence of still longer bonds compared to the model without Pd ion doping. Synergistic effect is, therefore, due to enhanced reducibility of both dopant and host ion induced due to structural distortion of fluorite lattice in presence of dopant ion. For RE ions (RE = Y, La) our calculations show very little deviation of bonds lengths from ideal fluorite structure. The absence of longer Y— O/La—O and Ce–O bonds make the structure very less susceptible to reduction [8]. Since Pd substituted Ce1–xSnxO2 showed high OSC and catalytic activity towards CO oxidation and NO reduction, we tested this catalyst for water-gas shift (WGS) reaction and the results are presented in chapter 7. Over 99.5 % CO conversion to H2 is observed at 300 ± 25 oC. Based on different characterization techniques we found that the present catalyst is resistant to deactivation due to carbonate formation and sintering of Pt on the surface when subjected to longer duration of reaction conditions. The catalyst does not require any pre-treatment or activation between start-up/shut-down reaction operations. Formation of side products such as methane, methanol, formaldehyde, coke etc. was not observed under the WGS reaction conditions indicating the high selectivity of the catalyst for H2. Temperature programmed reduction of the catalyst in hydrogen (H2–TPR) shows reversible reduction of Ce4+ to Ce3+, Sn4+ to Sn2+ and Pt4+ to Pt0 oxidation state with oxygen storage capacity (OSC) of 3500 μmol g–1 at 80 oC. Such high value of OSC indicates the presence of highly activated lattice oxygen. CO oxidation in presence of stoichiometric O2 shows 100 % conversion to CO2 at room temperature. The catalyst also exhibits 100% selectivity for CO2 at room temperature towards preferential oxidation (PROX) of residual CO in presence of excess hydrogen in the feed. To further validate our DFT results presented in the thesis, DFT calculations on Ce2Zr2O8–Ce2Zr2O7 system were performed and the results are given in the last chapter 8. Ce2Zr2O7 does not show any oxygen storage/release property unlike Ce2Zr2O8 (=Ce0.5Zr0.5O2). Bond lengths obtained from DFT simulation on Ce2Zr2O7 structure showed well-defined Ce—O and Zr—O bonds expected of the pyrochlore structure, unlike distribution of bond lengths as has been observed for Ce1–xMxO2–δ case. Absence of bonds distribution indicates that the oxygen sublattice is not distorted in Ce2Zr2O7 in agreement with its closed packed structure. Filling of the 1/8 of the tetrahedral oxide ion vacancies will result in Ce2Zr2O8 structure, and DFT calculation for this structure show wide distribution of bond lengths. Long Ce—O and Zr—O bonds appear in the bond-distribution plot, suggesting substantial distortion of the oxygen sublattice. Thus absence of longer cation-oxygen bond in pyrochlore structure validates the structural calculations presented in this thesis. Based on the results derived in all the chapters, a critical review of the work is presented and major conclusions are given in the last chapter
34

Illuminating solid gas storage in confined spaces – methane hydrate formation in porous model carbons

Borchardt, Lars, Nickel, Winfried, Casco, Mirian, Senkovska, Irena, Bon, Volodymyr, Wallacher, Dirk, Grimm, Nico, Krause, Simon, Silvestre-Albero, Joaquín 05 April 2017 (has links)
Methane hydrate nucleation and growth in porous model carbon materials illuminates the way towards the design of an optimized solid-based methane storage technology. High-pressure methane adsorption studies on pre-humidified carbons with well-defined and uniform porosity show that methane hydrate formation in confined nanospace can take place at relatively low pressures, even below 3 MPa CH4, depending on the pore size and the adsorption temperature. The methane hydrate nucleation and growth is highly promoted at temperatures below the water freezing point, due to the lower activation energy in ice vs. liquid water. The methane storage capacity via hydrate formation increases with an increase in the pore size up to an optimum value for the 25 nm pore size model-carbon, with a 173% improvement in the adsorption capacity as compared to the dry sample. Synchrotron X-ray powder diffraction measurements (SXRPD) confirm the formation of methane hydrates with a sI structure, in close agreement with natural hydrates. Furthermore, SXRPD data anticipate a certain contraction of the unit cell parameter for methane hydrates grown in small pores.
35

Hållbarhet på kapillära blodprover för analys av hemoglobin, leukocyter och trombocyter / Shelf life for analysis of haemoglobin, leukocytes and platelets in capillary blood samples

Johansson, Sara January 2022 (has links)
Inom klinisk verksamhet är det av stor betydelse att känna till hållbarheten på olika analyter för att säkerställa att analysen inte genomförs på för gamla prover. Vid litteratursökning framgick att bland de publicerade studier som undersökt hållbarheten på blodprover har de flesta undersökt hållbarheten på venösa men inte kapillära blodprover. En vanligt förekommande analys med både venösa och kapillära prover är blodstatus, som inkluderar bland annat bestämning av hemoglobinkoncentrationen (Hb-), leukocyt- samt trombocytpartikelkoncentrationen (LPK och TPK). Analys av blodets celler kan ge allmän information om hälsotillståndet hos patienter och är därav viktiga och vanligt förekommande analyser. Syftet med examensarbetet var att undersöka hållbarheten för analyserna Hb, LPK och TPK på kapillära blodprover efter fyra och sex timmars förvaring i rumstemperatur. Provmaterialet utgjordes av 100 kapillära prover som analyserades på hematologiinstrumentet Sysmex XN-10. Analysmetoden för Hb var fotometri med natriumlaurylsulfat- (SLS-) metoden. LPK bestämdes med flödescytometri medan TPK bestämdes med impedansmetoden alternativt flödescytometri. Resultatet visade att det för Hb inte förekom någon signifikant statistisk skillnad mellan den initiala analysen och efter fyra respektive sex timmar. Analysresultatet för Hb var därmed stabilt under förhållandena i denna studie. För LPK och TPK förekom statistiskt signifikanta skillnader mellan resultatet vid den initiala analysen jämfört med efter fyra respektive sex timmar. Analysresultaten för LPK och TPK var därmed inte lika stabila som Hb är under förhållandena i studien. Den statistiska skillnaden bedömdes däremot inte ha någon klinisk betydelse, vilket ledde till slutsatsen är att kapillära prover för analys av Hb, LPK och TPK är hållbara i sex timmar vid förvaring i rumstemperatur. / One important factor in clinical practice is understanding the stability of analytes and for how long blood samples can be stored before analysis. Most published studies are based on venous blood samples rather than capillary. The knowledge about storage time for cells in capillary blood is therefore limited. Plenty of information can be obtained by analysing the blood cells and its components, including haemoglobin, white blood cells and platelets. These analyses are therefore some of the most common in clinical practice. The aim of this study was to evaluate the effect of the analysis result for haemoglobin, white blood cells and platelets in capillary blood samples after storage at room temperature for four and six hours, respectively. In the study, 100 capillary samples from anonymous patients were analysed with the haematology analyser Sysmex XN-10. The method for analysing haemoglobin was the sodium lauryl sulphate (SLS) detection method with spectrophotometry. White blood cells were analysed with fluorescens flow cytometry. Platelets were analysed with either impedance or fluorescens flow cytometry. The result of the study showed no statistically significant difference between the initial analysis results in haemoglobin and at four and six hours, concluding that within the conditions of this study, the analysis result for haemoglobin was stable. Significant statical differences were identified for both white blood cells and platelet analysis results at four and six hours. However, the identified statistical significance was not esteemed to have any clinical relevance. In conclusion haemoglobin, white blood cells and platelets in capillary blood can be stored for at least six hours at room temperature.
36

Stanovení funkčních objemů nádrže s uvažováním nejistot vstupních dat / Determination of the functional volumes of the reservoir considering input data uncertainties

Paseka, Stanislav Unknown Date (has links)
Damaging changes and interventions in the water cycle in our landscape caused mainly in the last century together with uncertainties from climate change are the cause of more frequent occurrences of hydrological extremes. In Hydrology, the most urgent problem is that the values of the long-term mean flows are decreasing in rivers as well as the yield of groundwater sources, but on the other hand, we cannot forget to the problem of extreme floods. In these consequences developing methods and tools to uncertainty analysis of the reservoir yield and of the reservoir flood protection is very important, useful and desired. The main aim was to determine the functional volumes of the reservoir considering input data measurement uncertainties and to quantify them and was explained how uncertainty took into account in results. The active storage capacity was determined from the historical series of monthly flows that were affected by uncertainties, next were applied on water evaporation, seepage losses of the dam and morphological volume-area curves. The simulation-optimization reservoir model was developed and temporal reliability as reservoir yield performance measures was applied. This model will extend the existing UNCE_RESERVOIR software. The flood capacity was determined from random flood wave variations were obtained by repeatedly generating uncertainty on the flood hydrograph. Software was developed based on the modified Klemes method, which was able to transform flood waves. The measurement uncertainties of data inputs were created using Monte Carlo method in both softwares. By connecting two softwares, the functional volumes of the reservoir under conditions of measurement uncertainties were complexly determined. The case study was applied to the real water reservoir, in the Morava River Basin. The result will be whether the dam is resistant to the current conditions, or the optimal design of the functional volumes of reservoir under conditions uncertainties.
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Parâmetros de irrigação por análise numérica para a cultura do milho na região central do Rio Grande do Sul / Parameters of irrigation by numerical analysis for maize in the central area of Rio Grande do Sul

Trentin, Gustavo 27 February 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Maize is a main crop in Brazil. Maize yield can be decreased by water deficit. Irrigation is an alternative to overcome this problem and avoid the low soil water availability. In order to efficiently irrigate a crop it is necessary to know some parameters and irrigation and crop requirements in each region. The objective of this study was to determine the most likely values the duration of developmental phases, water depth and the number of irrigations required for maize crop sown at different sowing dates, considering the water storage capacity of main soils of the Central Area of Rio Grande do Sul State and its variation with simulated developmental stage. Crop development for three maturation groups was simulated using the thermal time, for 14 sowing dates, from August until mid-February, every during the period from 1968 to 2008, covered by metereorological data at Santa Maria RS (EMPSM). To 13 soils, were grouped into six groups with similar water storage capacity (CAD) and infiltration capacity. Daily water balance was calculated when soil reached a minimum fraction of available water, according to four management levels (water withdrawn from the soil reached 20%, 30%, 40% and 50% of CAD). Data analysis consisted of analysis of variance, mean comparison tests and probability distribution analysis of the duration of crop developmental phases and the entire developmental cycle, water depth and number of irrigations. Developmental until tasseling are larger in the earliest sowing date (01/08). After tasseling, the greater duration of developmental phases occurs in the latest sowing (15/02). The normal and lognormal distributions represent better the variation of the duration of maize development both for the duration of the phases and the entire cycle. Sowing dates from early October to early November result a greater need water depth considering the entire cycle, regardless of the soil and maturation group. The mid maturation group needs more water during the entire cycle for all sowing dates, and the very early maturation group has the lowest water requirement. The variation of water depth and the number of irrigations follow the normal, lognormal, gamma and Weibull probability distribution functions. For the 90% probability level the water depth varies between 31 and 171 mm and the number of irrigations varies between one and nineteen during the developmental cycle, depending on sowing date, maize maturation group and soil. / O milho é uma das principais culturas da Agricultura Brasileira. A cultura sofre grandes perdas quando submetida a deficiência hídrica. Para contornar esse problema e evitar a baixa disponibilidade de água no solo, a irrigação do milho é a principal alternativa. Mas para isso ocorrer de forma satisfatória é necessário conhecer os parâmetros de irrigação e a necessidade de irrigação do milho em cada região. O objetivo desse trabalho foi determinar os valores mais prováveis de duração dos subperíodos do ciclo de desenvolvimento, de lâmina de irrigação e de número de irrigações necessários para o milho semeado em diferentes épocas, considerando-se a capacidade de armazenamento de água disponível dos principais solos da Região Central do Estado do Rio Grande do Sul e sua variação com o desenvolvimento simulado das plantas. O desenvolvimento da cultura para os três grupos de maturação foi realizado através da soma térmica, para as 14 épocas de semeadura, do início do mês de agosto até meados de fevereiro, para cada ano do banco de dados da Estação Meteorológica Principal de Santa Maria RS (EMPSM), utilizando o período de 1968 a 2008. Para simular a irrigação, os 13 solos da região de abrangência da EMPSM, foram agrupados em seis grupos que apresentam características semelhantes de capacidade de armazenamento de água disponível (CAD) e capacidade de infiltração. O balanço hídrico diário determinou a variação da água disponível e o momento da irrigação. O momento da irrigação foi determinado quando os solos alcançavam a fração mínima de água disponível a ser mantida. Para isso, foram utilizados quatro manejos que representaram a condição de quando a água retirada do solo alcançava a fração 20%, 30%, 40% e 50% da CAD. A análise dos dados consistiu de análise de variância, teste de comparação de médias e análise de distribuição de probabilidade para as variáveis: duração dos subperíodos e do ciclo de desenvolvimento do milho, lâmina de irrigação e o número de irrigações. Os subperíodos que ocorrem da semeadura até o pendoamento são maiores na primeira semeadura (01/08). Após o pendoamento a maior duração dos subperíodos ocorre na semeadura mais tardia (15/02). As distribuições normal e lognormal representam melhor o desenvolvimento do milho podem ser usadas para a duração dos subperíodos e do ciclo total. As épocas de semeadura do início de outubro até o início de novembro necessitam de maiores lâminas de irrigação considerando todo o ciclo, independente do solo e grupo de maturação. O grupo de maturação normal necessita maior lâmina de irrigação durante o ciclo de cultivo para todas as épocas de semeadura, e o grupo de maturação superprecoce tem a menor lâmina. A lâmina de irrigação e o número de irrigações são representadas pelas funções de distribuição de probabilidade normal, lognormal, gamma e Weibull. Para a probabilidade de 90% de ocorrência, a lâmina de irrigação varia entre 31 e 171 mm e o número de irrigações entre uma e dezenove durante o ciclo de desenvolvimento da cultura, dependendo da época de semeadura, grupo de maturação do milho e do solo de cultivo.
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PARÂMETROS DE IRRIGAÇÃO PARA O FEIJOEIRO EM DIFERENTES SOLOS E ÉPOCAS DE SEMEADURA NA REGIÃO CENTRAL DO RIO GRANDE DO SUL / IRRIGATION PARAMETERS FOR COMMON BEAN IN DIFFERENT SOILS AND SOWING DATES IN THE CENTRAL REGION OF RIO GRANDE DO SUL

Silva, Joel Cordeiro da 24 March 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Common bean is produced in the entire territory of Brazil and it is the staple food of many Brazilians. In spite of being cultivated in a variety of meteorological conditions, common bean is a plant sensitive to environmental stresses, mainly water stress. To appropriately provide the plant with water, it is necessary to study the climate of the region and the sowing times. Such information will be helpful to decide if the irrigation is recommended or not, and when recommended, its best planning. The objective of this study was to determine the most probable value of the duration of the cycle and the developmental phases, the irrigation requirements and the number of irrigations necessary for common bean cultivated during different sowing dates, considering the storage capacity of available water (CAD) of some of the main soils of the Central Region of the Rio Grande do Sul State, Brazil. The simulation of the developmental cycle was performed using thermal time units, in ten sowing dates (ES) and in each year of the meteorological database, from 1968 to 2006. Meteorological data were collected in the main meteorological station (MS) at Santa Maria - RS Irrigation was simulated for 13 soils in the surroundings of the MS, organized in six groups according to CAD and texture. In simulating the irrigation it were used four managements: 0.8, 0.7, 0.6 and 0.5 which correspond to the maximum uptake of 20%, 30%, 40% and 50% of CAD, respectively. The variation of the amount of water in the soil was calculated through daily water balance, considering the irrigation. Data obtained, such as the entire cycle duration and developmental phases, and the amount and number of irrigations, was submitted to analysis variance, tests of means comparison and analysis of probability distribution. The normal probability density function (fdp) was used to study the developmental cycle and the duration of the developmental phases. For the irrigation requirements and the number of irrigations, the gamma fdp was used in most cases, because of a best fit of the data. When it was not possible to adjust any fdp the empirical distribution was used. The developmental cycle has a variable duration with average values between 81 and 121 days, being shorter at the end of the spring growing season. The irrigation requirement and the number of irrigations were influenced by ES and soil type. The largest demand of water supply takes place at the end of the spring growing season and the smallest one in the beginning of the spring growing season and during the autumn growing season. For a likelihood of 90% the irrigation requirement varied between 32 and 143 mm and the number of irrigations between 3 and 20 times during the growing season. / O feijão é uma leguminosa bastante cultivada no Brasil, sendo o principal alimento de muitos brasileiros. Apesar de ser cultivado em diferentes condições climáticas, o feijoeiro é uma planta bastante sensível a estresses ambientais, notadamente a deficiência hídrica. Para suprir adequadamente a planta com água é necessário estudar o clima da região e das épocas de cultivo. As informações obtidas irão ajudar na tomada de decisões da adoção ou não da irrigação e, quando recomendada, seu melhor planejamento. O objetivo desse estudo foi determinar os valores mais prováveis de duração do ciclo e subperíodos, de lâmina de irrigação e do número de irrigações necessários para o feijão semeado em diferentes épocas, considerando-se a capacidade de armazenamento de água disponível (CAD) dos principais solos da região Central do Rio Grande do Sul. A simulação do ciclo foi realizada utilizando-se a soma térmica, em dez épocas de semeadura (ES) e em cada ano da séria histórica de dados meteorológicos, para o período entre 1968 e 2006. Os dados meteorológicos foram coletados na estação meteorológica principal de Santa Maria RS (EMPSM). A irrigação foi simulada para 13 solos da região de abrangência da EMPSM, que foram reunidos em seis grupos, de acordo com sua CAD e sua textura. Para simular a irrigação, utilizaram-se quatro manejos: 0,8; 0,7; 0,6 e 0,5 os quais correspondem ao esgotamento máximo de 20%, 30%, 40% e 50% da CAD, respectivamente. A variação do conteúdo de água no solo foi determinada pelo balanço hídrico diário do solo, considerando-se a irrigação. Os dados de duração do ciclo e dos subperíodos, assim como a lâmina e o número de irrigações foram submetidos à análise de variância, teste de comparação de médias e análise de distribuição de probabilidade. A função de distribuição de probabilidades (fdp) normal foi utilizada para estudar a distribuição da duração do ciclo e de suas etapas. Para a lâmina de irrigação e o número de irrigações utilizou-se a fdp gamma, na maioria dos casos, por apresentar melhor ajuste aos dados. Quando não foi possível ajustar nenhuma fdp, utilizou-se a distribuição empírica. Verificou-se que o ciclo tem duração variável conforme a ES com médias entre 81 e 121 dias, sendo mais curto no final do período de safra. A lâmina e o número de irrigações foram influenciados pela ES e tipo de solo. A maior exigência de suplementação hídrica acontece nas últimas ES do período da safra e a menor no início da safra e na safrinha. Para a probabilidade de 90% de ocorrência a lâmina de irrigação variou entre 32 e 143 mm e o número de irrigações entre três e 20 vezes no ciclo de cultivo.
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Probabilidade de ocorrência de deficiência hídrica na cultura do girassol na região central do Rio Grande do Sul / Occurrence probability of water deficit in sunflower crop in the central region of Rio Grande do Sul

Maldaner, Ivan Carlos 09 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In Brazil over recent years the interest increased on the sunflower cultivation. Sunflower yield can be decreased by water deficit. To solve this problem, is necessary to calculate the probable water deficit in critical sunflower sub-phases and in the whole development cycle at different sowing dates. The objective of this study was to determine the probable duration values of sub-phases and the developmental cycle and get sowing dates with lower risk of water deficit and the occurrence probability in different levels of water deficit during the developmental sub-phases of sunflower crop sown at different sowing dates, considering the water storage capacity in different soils in the Central Region of Rio Grande do Sul. Also determine the probability of occurrence of water stress for different years classified as the El Niño Southern Oscilation (ENSO). Crop development was simulated using the thermal time method, for 14 sowing dates, from August until mid-February, for every year during the period from 1968 to 2011, covered by database of Meteorological Station of Santa Maria, RS. For calculating the water deficit, the 13 soils were grouped into six groups with similar water storage capacity (CAD) and infiltration capacity. The water deficit was calculated from daily water balance. Data analysis consisted of analysis of variance, means comparison tests and analysis of probability distribution for the variables: duration of crop developmental sub-phases and the whole developmental cycle of the sunflower, water deficit in the sub-phases and whole developmental cycle. The length of the sub-phases and the development cycle of the sunflower crop are variable depending on sowing date. The length of the developmental sub-phases that occur from sowing until flower bud visible of sunflower are higher in the earliest sowing date (01/08). After anthesis, the longer length of developmental sub-phases occurs in the latest sowing (16/02). The lognormal, normal and gamma distributions represent better the development of sunflower to estimate the length of the phases and the whole cycle. At sowing date of 16/12, for 90% probability level, sunflower has the shortest length of the developmental cycle ending the cycle in a maximum of 96 days. The longer length of the sunflower cycle occurs at sowing date of 01/08, which reaches 132 days, at 90% level of occurrence probability. The sowing dates from early October until early November are the ones with the highest water deficit, considering the whole development cycle of the sunflower regardless of soil, a different choice on sowing date reduces the risk and the level of water deficit in sunflower cycle. In the soils in which the water storage capacity is lower, water deficit is greater in sub-phases as in the full cycle of the sunflower compared to other soils and is little variable among the sowing dates. Sunflower Sowings in the first half of August and since December are the ones with the lowest risk occurrence of water deficit during the more critical sub-phase of sunflower crop, at least there are favorable conditions for sowing and initial establishment of plants. / No Brasil nos últimos anos elevou-se o interesse pelo cultivo do girassol. Quando submetida à deficiência hídrica a cultura do girassol apresenta redução na produtividade. Para contornar esse problema, é necessário calcular a provável deficiência hídrica nos subperíodos críticos e no ciclo de desenvolvimento do girassol para cada uma das diferentes datas de semeadura. O objetivo desse trabalho foi determinar os valores prováveis de duração dos subperíodos e do ciclo de desenvolvimento e obter as datas de semeadura com menor risco de deficiência hídrica e a probabilidade de ocorrência de diferentes níveis de déficit hídrico durante os subperíodos de desenvolvimento do girassol semeado em datas de semeadura distintas, considerando a capacidade de armazenamento de água nos diferentes solos da região central do RS. Também determinar a probabilidade de ocorrência de deficiência hídrica para os diferentes anos classificados conforme o fenômeno El Niño Oscilação Sul (ENOS). O desenvolvimento da cultura foi simulado por meio do método da soma térmica, para 14 datas de semeadura, do início do mês de agosto até meados de fevereiro, para cada ano do banco de dados da Estação Meteorológica Principal de Santa Maria, RS, utilizando o período de 1968 a 2011. Para calcular a deficiência hídrica, os 13 solos da região foram agrupados em seis grupos que apresentam características semelhantes de capacidade de armazenamento de água disponível (CAD) e capacidade de infiltração. As deficiências hídricas foram determinadas a partir do balanço hídrico diário. A análise dos dados consistiu na análise da variância, teste de comparação de médias e análise de distribuição de probabilidade para as variáveis: duração dos subperíodos e do ciclo de desenvolvimento do girassol, deficiência hídrica nos subperíodos e no ciclo do girassol. A duração dos subperíodos e do ciclo de desenvolvimento do girassol é variável conforme a data de semeadura. A duração dos subperíodos que ocorrem da semeadura até o botão floral visível do girassol são maiores na primeira data de semeadura (01/08). Após a antese a maior duração dos subperíodos ocorre na semeadura mais tardia (16/02). As distribuições lognormal, normal e gama representam melhor o desenvolvimento do girassol para estimar a duração dos subperíodos e do ciclo. Na data de semeadura de 16/12, ao nível de 90% de probabilidade de ocorrência, o girassol tem a menor duração do ciclo, completando o ciclo em no máximo de 96 dias. A maior duração do ciclo do girassol ocorre na data de semeadura de 01/08, na qual alcança 132 dias, em nível de 90% de probabilidade de ocorrência. As datas de semeadura de início de outubro até o início de novembro são as que apresentam a maior deficiência hídrica, considerando todo o ciclo de desenvolvimento do girassol independente do solo; a escolha de outra data de semeadura reduz o risco e o nível de deficiência hídrica durante o ciclo do girassol. Nos solos em que a capacidade de armazenamento de água disponível é menor, a deficiência hídrica é maior tanto nos subperíodos quanto no ciclo do girassol em relação aos demais solos e é pouco variável ao longo das datas de semeadura. Semeaduras de girassol na primeira quinzena de agosto e a partir do mês de dezembro são as que apresentam os menores riscos de ocorrer deficiência hídrica no transcorrer do subperíodo mais crítico do girassol, desde que se tenham condições favoráveis para a semeadura e o estabelecimento inicial das plantas.
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PARÂMETROS E PROBABILIDADES DE IRRIGAÇÃO PARA A CULTURA DA SOJA NA REGIÃO CENTRAL DO RIO GRANDE DO SUL POR ANÁLISE NUMÉRICA / PROBABILITY AND PARAMETERS OF IRRIGATION FOR SOYBEAN CROP IN CENTRAL REGION OF RIO GRANDE DO SUL BY NUMERICAL ANALYSIS

Trentin, Roberto 22 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to determine the probable duration of the developmental phases of the cycle for the soybean at different sowing dates, the average values of water depth and number of irrigations needed and also its relationship with El Niño Oscillation South (ENSO), considering the capacity of water storage available (CAD) of the main soils of Central region of Rio Grande do Sul. This study was conducted by means of mathematical models of development of soybean and data published in the literature meteorological, climatological station collected in Santa Maria, RS (latitude: 29°43'23 "S, longitude: 53° 43'15" W and altitude: 95 m), from October 1968 to July 2012, totaling 44 years of daily observations. The simulation of crop development was carried out for different sowing dates every ten days, considering three maturity groups (GM): 5.9-6.8 6.9-7.3 and 7.8-8.0. To simulate irrigation, the 13 soils of the region covered in this study into five groups that have similar characteristics of water storage capacity available (CAD) and infiltration capacity. The daily water balance determined the variation of water availability and timing of irrigation. The timing of irrigation was determined when the soil reached a minimum fraction of available water to be maintained. For this, we used four handlings representing the condition when the water withdrawn from the soil fraction reached 20%, 30%, 40% and 50% of the CAD. Data analysis consisted of analysis of variance test for comparison of means and analysis of the probability distribution for the variables: duration of subperiods and development cycle of soybeans, water depth, number of irrigation and water depth associated to ENSO. The average duration of subperiods and soybean development cycle varies according to the date of sowing. The duration of the development cycle of the soybean crop is higher in the early sowing dates (October) decreasing until the last sowing dates (December). Early sowing dates require more water depth than the latest sowing dates. It was found that higher water depth necessary to soybean is associated with neutral years, while the lowest water depth is related to El Niño events. / O objetivo deste trabalho foi determinar os valores prováveis de duração dos subperíodos do ciclo para a cultura da soja semeada em diferentes datas, os valores Médios de lâmina de irrigação e do número de irrigações necessários e também sua relação com o fenômeno El Niño Oscilação Sul (ENOS), considerando-se a capacidade de armazenamento de água disponível (CAD) dos principais solos da região Central do Rio Grande do Sul. Este estudo foi realizado por meio de modelos matemáticos de desenvolvimento da cultura da soja publicados na literatura e dados meteorológicos, coletados na estação climatológica principal de Santa Maria, RS (latitude: 29°43 23‖ S, longitude: 53°43 15‖ W e altitude: 95 m), desde outubro de 1968 até julho de 2012, totalizando 44 anos de observações diárias. A simulação do desenvolvimento da cultura foi realizada para diferentes datas de semeadura, aproximadamente a cada dez dias, de acordo com os três grupos de maturação (GM) avaliados: 5.9 6.8 (Ciclo precoce/semiprecoce,), 6.9 7.3 (Ciclo médio,) e 7.8 8.0 (Ciclo semitardio/tardio). Para simular a irrigação, os 13 solos da região de abrangência do estudo, foram agrupados em cinco grupos que apresentam características semelhantes de capacidade de armazenamento de água disponível (CAD) e capacidade de infiltração. O balanço hídrico sequencial diário determinou a variação da água disponível e o momento da irrigação. O momento da irrigação foi determinado quando os solos alcançavam a fração mínima de água disponível a ser mantida. Para isso, foram utilizados quatro manejos que representaram a condição de quando a água retirada do solo alcançava a fração 20%, 30%, 40% e 50% da CAD. A análise dos dados consistiu de análise de variância, teste de comparação de médias e análise de distribuição de probabilidade para as variáveis: duração dos subperíodos e do ciclo de desenvolvimento da cultura da soja, lâmina de irrigação, número de irrigações a lâmina de irrigação associada o fenômeno ENOS. A duração média dos subperíodos e do ciclo de desenvolvimento da soja é variável conforme a data de semeadura. A duração do ciclo de desenvolvimento da cultura da soja é maior nas primeiras datas de semeadura (outubro) decrescendo até as últimas datas de semeadura (dezembro). As primeiras datas de semeadura necessitam de maior lâmina de irrigação do que as últimas datas de semeadura. Constatou-se que maior lâmina de irrigação necessária à cultura da soja está associada a anos neutros, enquanto que a menor lâmina de irrigação está relacionada a eventos de El Niño.

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