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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.
101

NOZZLE TYPE AND ARRANGEMENT ALTERNATIVES FOR IMPROVED APPLICATION OF SUCKERCIDES IN BURLEY TOBACCO (<i>Nicotiana tabacum</i> L.)

Neal, Beau Robert 01 January 2011 (has links)
Maleic hydrazide (MH) applications have been standard practice for sucker control in burley tobacco (Nicotiana tabacum L.) production for the last half-century because it is relatively inexpensive, effective and easy to apply. Non-MH suckercides such as fatty alcohols and local systemics can be utilized to reduce or replace MH and lower undesirable residues in the cured leaf. The objective of this study was to evaluate various nozzle types and arrangements for efficiency to determine if sucker control with fatty alcohol could be consistently improved over the currently used TG3-5-3 arrangement, as well as examine sprayer positioning (center vs. off-center) and leaf orientation variables using artificial plants. In the field study, the TG4-6-4 arrangement performed the best (p<0.05) when applying the same volume per hectare providing 80% sucker control with fatty alcohol only, not significantly different (p>0.05) than MH+Butralin treatment. For the artificial plant study, the TG4-6-4 provided more solution collected (p<0.05) at leaf axils as well as the highest percent of solution intercepted. Sprayer position and leaf orientation had less effect on solution intercepted with this arrangement than it did with the TG3-5-3. Results from this study support a recommendation of the TG4-6-4 over the TG3-5-3 for the application of contact chemicals for sucker control in burley tobacco.
102

EXPERIMENTAL STUDY OF ACTIVE SEPARATION FLOW CONTROL IN A LOW PRESSURE TURBINE BLADE CASCADE MODEL

McQuilling, Mark 01 January 2004 (has links)
The flow field around a low pressure turbine (LPT) blade cascade model with and without flow control is examined using ejector nozzle (EN) and vortex generator jet (VGJ) geometries for separation control. The cascade model consists of 6 Pak-B Pratt andamp; Whitney low pressure turbine blades with Re = 30,000-50,000 at a free-stream turbulence intensity of 0.6%. The EN geometry consists of combined suction and blowing slots near the point of separation. The VGJs consist of a row of holes placed at an angle to the free-stream, and are tested at two locations of 69% and 10.5% of the suction surface length (SSL). Results are compared between flow control on and flow control off states, as well as between the EN, VGJs, and a baseline cascade with no flow control geometry for steady and pulsatile blowing. The EN geometry is shown to control separation with both steady and pulsatile blowing. The VGJs at 69% SSL are shown to be much more aggressive than the EN geometry, achieving the same level of separation control with lower energy input. Pulsed VGJs (PVGJ) have been shown to be just as effective as steady VGJs, and results show that a 10% duty cycle is almost as effective as a 50% duty cycle. The VGJs at 10.5% SSL are shown to be inefficient at controlling separation. No combination of duty cycle and pulsing frequency tested can eliminate the separation region, with only higher steady blowing rates achieving separation control. Thus, the VGJs at 69% SSL are shown to be the most effective in controlling separation.
103

Nozzle Blockage In Continuous Casting Of Al-killed Sae 1006 And Sae 1008 Steel Grades In Iskenderun Iron And Steel Works

Sakalli, Erhan 01 April 2004 (has links) (PDF)
In this work, nozzle clogging in the submerged entry nozzle in continuous casting of Al killed steels has been studied. The study has been based on low silicon Al killed SAE 1006 (1.2006) and SAE 1008 (1.2008) grades. In this study, castabilities of 75 heats for 1.2006 steel grades and 75 heats for 1.2008 steel grades have been investigated. Castabilities of the experimental heats have been found to be affected by Al content in oxide form (Aloxy) and Ca content of the liquid steel. Castabilities have been found to decrease with increase in Aloxy and to increase with increase in Ca content and Ca/Aloxy ratio. Reoxidation has been found not to affect the castability appreciably.
104

Scaling of effervescent atomization and industrial two-phase flow

Rahman, Mohammad 06 1900 (has links)
The objective of this thesis was to develop a novel understanding of the mechanics of two phase gas-liquid flows and sprays injected through industrial effervescent nozzles. This was done using detailed experimental investigations and scaling for two-phase flows and sprays. This study helps to quantify near-field liquid and gas phase statistics that are challenging and impossible to measure in the reactors due to inaccessibility restrictions. The development of nozzles is generally performed on air-water systems. My plan was to begin with the study of small-scale sprays (air and water) to compare to full scale industrial conditions at pilot operation (air-water) or at commercial operation (steam-bitumen), to determine size scaling relationships. The relationship between the lab scale air-water experiments and real industrial scale steam-bitumen has never been fully examined. Knowledge from this thesis will make the development of future nozzles with much less dependent on trial and error. This thesis was an attempt to establish fundamental scaling relationships for the prediction of two-phase spray behavior that can be applied directly to full scale industrial size nozzles that would be of very significant value to industries and to the scientific community in general. Understanding the performance of two phase nozzles through established scaling laws will aid in optimizing the two phase nozzle flow conditions and will serve as a major tool in nozzle design and development for future generation nozzles for many industrial applications.
105

Desenvolvimento de métodos para estimar a quantidade de ar incluído às gotas por pontas de pulverização com indução de ar

Faggion, Francisco [UNESP] 12 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-12Bitstream added on 2014-06-13T20:22:31Z : No. of bitstreams: 1 faggion_f_dr_botfca.pdf: 657295 bytes, checksum: 26059548a93d7a2ab049396262cee9db (MD5) / As pontas de pulverização são componentes importantes dos sistemas utilizados para a aplicação de defensivos agrícolas por permitirem a alteração das características da aplicação. Às pontas de pulverização com indução de ar, desenvolvidas recentemente, é atribuída a possibilidade de redução da deriva, o que tem contribuído para sua popularização. O objetivo do trabalho foi desenvolver e avaliar métodos para determinar a quantidade de ar incluído às gotas do líquido aspergido por diferentes pontas de pulverização. O spray de gotas com ar em seu interior foi capturado em um funil para determinar a porcentagem de ar nelas contido. Para medir as forças de impacto das gotas foi utilizada uma placa de impacto. Um coletor com as mesmas dimensões de coleta que a placa foi posicionado na mesma posição e orientação do spray, para medir o fluxo de líquido. Em seguida foi calculada a velocidade das gotas. Quatro modelos de pontas de pulverização de jato plano com indução de ar e um modelo convencional foram utilizados. Em cada modelo utilizou-se uma série de pontas com vazões 015, 02, 03 e 04, todas com ângulo de aspersão do jato de 110o. Foram utilizadas, ainda, outras cinco diferentes pontas com indução de ar 02 e 04, de dois modelos, para avaliações de homogeneidade dos resultados entre pontas de mesmo modelo e vazão. Para realizar os testes foi utilizada a solução obtida da mistura de água com 0,1% de um adjuvante não iônico (Agral). Essa solução foi submetida às pressões de trabalho 200, 250, 300, 350 e 400 kPa em todas as pontas de pulverização testadas. Os métodos estudados foram desenvolvidos e avaliados e metodologias de trabalho foram propostas... / Agricultural nozzles are important components of the systems used to apply agrochemicals because they allow alterations in terms of the characteristics of an application. To the recently developed air induction nozzles it is attributed the possibility of drift reduction, which contributes to make them more popular. The aim of this study was to develop and to evaluate methods for assessing the amount of air included in the droplets spread by different agricultural nozzles. The spray droplets with air in their interior were captured in a funnel in order to determine the percentage of air in them. An impact plate to measure the droplets impact forces was used. In order to measure the liquid flow a collector with the same area of the impact plate was placed on the same position and orientation of the spray. After data collection the droplets velocity was calculated. Four designs of air induction nozzles and one design of flat fan nozzle were used. In each design a series of nozzles with output of 015, 02, 03 and 04, all with 110o spray angle was used. It was used other five different air induction nozzles 02 and 04 with two different designs to evaluate the homogeneity of results between nozzles with the same design and output. To do the tests it was used the solution obtained from the mixture of tap water with 0,1% of a non-ionic adjuvant (Agral). That solution was submitted to 200, 250, 300, 350, and 400 kPa work pressures in all nozzles tested. The studied methods were developed and tested and working methodologies were proposed. The method of capturing the spray droplets and the determination of the percentage of air included quantified accurately the air induced and established the differences among the nozzles according to the quantity of air induced. That method can be used when setting up norms in order to classify the air induction nozzles...(Complete abstract, click electronic access below)
106

Nozzle Design for Vacuum Aerosol Deposition of Nanostructured Coatings

January 2017 (has links)
abstract: Nanomaterials exhibit unique properties that are substantially different from their bulk counterparts. These unique properties have gained recognition and application for various fields and products including sensors, displays, photovoltaics, and energy storage devices. Aerosol Deposition (AD) is a relatively new method for depositing nanomaterials. AD utilizes a nozzle to accelerate the nanomaterial into a deposition chamber under near-vacuum conditions towards a substrate with which the nanomaterial collides and adheres. Traditional methods for designing nozzles at atmospheric conditions are not well suited for nozzle design for AD methods. Computational Fluid Dynamics (CFD) software, ANSYS Fluent, is utilized to simulate two-phase flows consisting of a carrier gas (Helium) and silicon nanoparticles. The Cunningham Correction Factor is used to account for non-continuous effects at the relatively low pressures utilized in AD. The nozzle, referred to herein as a boundary layer compensation (BLC) nozzle, comprises an area-ratio which is larger than traditionally designed nozzles to compensate for the thick boundary layer which forms within the viscosity-affected carrier gas flow. As a result, nanoparticles impact the substrate at velocities up to 300 times faster than the baseline nozzle. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2017
107

Aspectos qualitativos e quantitativos em pulverização na cultura do amendoim e Brachiaria plantaginea (Link) Hitch /

Rodrigues, Andréia Cristina Peres, 1978- January 2010 (has links)
Orientador: Dagoberto Martins / Banca: Carlos Gilberto Raetano / Banca: Maurício Dutra Zanotto / Banca: Marcelo da Costa Ferreira / Banca: Fernando Tadeu de Carvalho / Resumo: Objetivou-se avaliar a quantidade e qualidade da deposição da calda de pulverização em duas cultivares de amendoim (Aracahis hypogaea L.) e na planta daninha Brachiaria plantaginea (Link) Hitch., presente na linha e entrelinhas de semeadura da cultura, além da deposição no solo, em aplicações de pós-emergência. O estudo foi realizado a campo com duas cultivares de amendoim ('IAC Tatu-ST' e 'Runner IAC 886'), sendo as aplicações dos tratamentos realizadas nos estádios vegetativo (V1) e reprodutivo (R2). Foi utilizado como marcador o corante Azul Brilhante FDC -1 na concentração de 500 ppm. Os tratamentos foram constituídos por sete pontas de pulverização: XR 110015 VS (150 L ha-1), XR 11002 VS (200 L ha-1), TX-VK 6 (150L ha-1), TX-VK 8 (200 L ha-1), AI 110015 VS (150 L ha-1), AI11002 VS (200 L ha-1) e TJ60 11002 VS (150 e 200 L ha-1). Utilizou-se o delineamento em blocos ao acaso, com 4 repetições. Os dados dos resultados quantitativos de deposição foram analisados nos seguintes esquemas em fatorial: para os depósitos em plantas de amendoim foi utilizado o esquema 8 x 2 (8 situações de pulverização x 2 estádio de desenvolvimento da cultura); para as plantas daninhas presentes na linha e na entrelinha da cultura do amendoim, o esquema foi 8 x 2 [8 situações de pulverização x 2 posições (linha e entrelinha)]; para as estimativas de deposição no solo, o esquema foi 8 x 2 [8 situações de pulverização x 2 posições (linha e entrelinha)]. Foram amostradas 25 plantas por repetição em cada parcela, tanto para as plantas de amendoim quanto para as plantas daninhas presentes na linha e na entrelinha da cultura. Após a aplicação, as plantas foram imediatamente coletadas, e em seguida foram lavadas em 100 mL de água destilada para posterior quantificação do marcador em espectrofotômetro. Para as análises qualitativas, cada planta selecionada... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate the quantity and quality of the spray deposition in two peanut cultivars (Aracahis hypogaea L.) and weed Brachiaria plantaginea (Link) Hitch., current in the crop row and spacing row, beyond the deposition in soil, in applications of post-emergency. The study was conducted in the field with two peanut cultivars ('IAC Tatu-ST' e 'Runner IAC 886'), and the applications of treatments performed in the vegetative stage (V1) and reproductive (R2). It was used the Brilliant Blue FDC - 1 as tracer in water solution, at 500 ppm. The treatments consisted of seven spray nozzle XR 110015 VS (150 L ha-1), XR 11002 VS (200 L ha-1), TX-VK 6 (150L ha-1), TX-VK 8 (200 L ha-1), AI 110015 VS (150 L ha-1), AI11002 VS (200 L ha-1) e TJ60 11002 VS (150 e 200 L ha1). It was used a randomized blocks design, with four replications. Being that, the results of the quantitative data of deposition had been analyzed in following factorial schemes: for the deposits in peanut plants was used 8 x 2 factorial scheme (8 situations spray x stage of development of culture), for the Brachiaria plantaginea plants was used 8 x 2 factorial scheme [8 situations spray x 2 positions (row and spacing row)]; for the soil deposition estimates, the factorial scheme was 8 x 2 [8 situations spray x 2 positions (row and spacing row)]. Were sampled 25 plants for replication in each plot, as much for the peanut plants as current weeds in crop row and spacing row. After application, the plants were immediately collected, and after they had been washed in 100 mL of distilled water for tracer remover. The tracer quantification was made in spectrophotometer. For the quantitative analysis, each random selected plant inside of boom application stripe bar was considered a replication, representing a total of 100 replications. The obtained data had been adjusted a regression curve for Gompertz... (Complete abstract click electronic access below) / Doutor
108

Aspectos qualitativos e quantitativos em pulverização na cultura do amendoim e Brachiaria plantaginea (Link) Hitch

Rodrigues, Andréia Cristina Peres [UNESP] 28 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-28Bitstream added on 2014-06-13T20:20:54Z : No. of bitstreams: 1 rodrigues_acp_dr_botfca.pdf: 1795519 bytes, checksum: 01aaad09fd46e8ad27dfbe72f219e641 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivou-se avaliar a quantidade e qualidade da deposição da calda de pulverização em duas cultivares de amendoim (Aracahis hypogaea L.) e na planta daninha Brachiaria plantaginea (Link) Hitch., presente na linha e entrelinhas de semeadura da cultura, além da deposição no solo, em aplicações de pós-emergência. O estudo foi realizado a campo com duas cultivares de amendoim (‘IAC Tatu-ST’ e ‘Runner IAC 886’), sendo as aplicações dos tratamentos realizadas nos estádios vegetativo (V1) e reprodutivo (R2). Foi utilizado como marcador o corante Azul Brilhante FDC -1 na concentração de 500 ppm. Os tratamentos foram constituídos por sete pontas de pulverização: XR 110015 VS (150 L ha-1), XR 11002 VS (200 L ha-1), TX-VK 6 (150L ha-1), TX-VK 8 (200 L ha-1), AI 110015 VS (150 L ha-1), AI11002 VS (200 L ha-1) e TJ60 11002 VS (150 e 200 L ha-1). Utilizou-se o delineamento em blocos ao acaso, com 4 repetições. Os dados dos resultados quantitativos de deposição foram analisados nos seguintes esquemas em fatorial: para os depósitos em plantas de amendoim foi utilizado o esquema 8 x 2 (8 situações de pulverização x 2 estádio de desenvolvimento da cultura); para as plantas daninhas presentes na linha e na entrelinha da cultura do amendoim, o esquema foi 8 x 2 [8 situações de pulverização x 2 posições (linha e entrelinha)]; para as estimativas de deposição no solo, o esquema foi 8 x 2 [8 situações de pulverização x 2 posições (linha e entrelinha)]. Foram amostradas 25 plantas por repetição em cada parcela, tanto para as plantas de amendoim quanto para as plantas daninhas presentes na linha e na entrelinha da cultura. Após a aplicação, as plantas foram imediatamente coletadas, e em seguida foram lavadas em 100 mL de água destilada para posterior quantificação do marcador em espectrofotômetro. Para as análises qualitativas, cada planta selecionada... / The objective of this study was to evaluate the quantity and quality of the spray deposition in two peanut cultivars (Aracahis hypogaea L.) and weed Brachiaria plantaginea (Link) Hitch., current in the crop row and spacing row, beyond the deposition in soil, in applications of post-emergency. The study was conducted in the field with two peanut cultivars (‘IAC Tatu-ST’ e ‘Runner IAC 886’), and the applications of treatments performed in the vegetative stage (V1) and reproductive (R2). It was used the Brilliant Blue FDC – 1 as tracer in water solution, at 500 ppm. The treatments consisted of seven spray nozzle XR 110015 VS (150 L ha-1), XR 11002 VS (200 L ha-1), TX-VK 6 (150L ha-1), TX-VK 8 (200 L ha-1), AI 110015 VS (150 L ha-1), AI11002 VS (200 L ha-1) e TJ60 11002 VS (150 e 200 L ha1). It was used a randomized blocks design, with four replications. Being that, the results of the quantitative data of deposition had been analyzed in following factorial schemes: for the deposits in peanut plants was used 8 x 2 factorial scheme (8 situations spray x stage of development of culture), for the Brachiaria plantaginea plants was used 8 x 2 factorial scheme [8 situations spray x 2 positions (row and spacing row)]; for the soil deposition estimates, the factorial scheme was 8 x 2 [8 situations spray x 2 positions (row and spacing row)]. Were sampled 25 plants for replication in each plot, as much for the peanut plants as current weeds in crop row and spacing row. After application, the plants were immediately collected, and after they had been washed in 100 mL of distilled water for tracer remover. The tracer quantification was made in spectrophotometer. For the quantitative analysis, each random selected plant inside of boom application stripe bar was considered a replication, representing a total of 100 replications. The obtained data had been adjusted a regression curve for Gompertz... (Complete abstract click electronic access below)
109

Efeito de pontas de pulverização e de arranjos populacionais de plantas de Eichhornia crassipes (Mart.) Solms., Salvinia auriculata Aubl. e Pistia stratiotes L. na deposição de calda de pulverização

Marchi, Sidnei Roberto de [UNESP] 16 March 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-16Bitstream added on 2014-06-13T20:00:32Z : No. of bitstreams: 1 marchi_sr_dr_botfca.pdf: 984466 bytes, checksum: 1469adadcc88f867eee451598ff9f2f3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho teve como objetivo avaliar a quantidade de calda de pulverização depositada na água e em folhas de Eichhornia crassipes (Mart.) Solms, Salvinia auriculata Aubl e Pistia stratiotes L. em condições variáveis de arranjos populacionais e dois tipos de pontas de pulverização (ConeJet TXVK-8 e TeeJet DG 11002 VS). Para tanto, foi conduzido um experimento em caixas d água composto por três Situações distintas. Na Situação Aguapé, além da proporção de dominância total correspondente à cobertura de 100% da caixa d água pelas plantas de aguapé, foram utilizados os arranjos (ou proporções) com as espécies de salvinia ou alface d água a 75%:25%, 50%:50%, 25%:75%. Adotou-se as mesmas proporções na Situação Salvínia e na Situação Alface d água, sendo que cada Situação foi determinada pela predominância total de salvínia ou alface d água, respectivamente, na caixa d água. Uma densidade tripla, onde as três espécies foram igualmente dispostas na proporção de 33,33%, foi utilizada como testemunha. Soluções dos corantes Amarelo Tartrasina FDC-5 a 3.500 ppm e Azul Brilhante FDC-1 a 1.000 ppm foram utilizados como traçadores para as pontas TXVK-8 e DG 11002VS, respectivamente. A pulverização de ambas soluções foram efetuadas na mesma unidade experimental, com um intervalo de 30 minutos entre si, através de um pulverizador costal pressurizado com CO2 e calibrado de modo a proporcionar um volume de aplicação aproximado de 200 L/ha. Amostras de água dos reservatórios foram coletadas antes e após as aplicações com o objetivo de avaliar a quantidade de calda de pulverização que não atingiu o alvo. Imediatamente após a coleta da 2 água, as plantas presentes nos reservatórios foram lavadas com água destilada até remoção total dos corantes depositados nas folhas. Placas de plástico contendo... / The present research had as objective to quantify the spray deposition on water and leaves of water hyacinth (Eichhornia crassipes (Mart.) Solms), water fern (Salvinia auriculata Aubl.) and water lettuce (Pistia stratiotes L.) according to various population arrangements and two nozzle type (ConeJet TXVK-8 and TeeJet 11002VS). The trial was carried out under reservoirs conditions using three different Situations. At Water hyacinth Situation, besides the total dominancy proportion equivalent to 100% of reservoir covering by water hyacinth plants, it was used three others combinations involving water hyacinth and water fern or water lettuce plants, as following: 75%:25%, 50%:50% and 25%:75%. The same combinations were also used at Water Fern Situation and Water Lettuce Situation, being each Situation determined by total dominancy of water fern or water lettuce in the 4 reservoirs, respectively. A triple ratio, where the three species were equally disposed at proportion of 33,33%, was used as check. Dye solutions of FD&C Yellow n. 5 at 3,500 ppm and FD&C Blue n. 1 at 1,000 ppm were used as spraying tracers for TXVK-8 and DG 11002 VS nozzles, respectively. Both solutions were sprayed at same plot within at 30 minutes interval each one through a CO2 pressured backpack knapsack calibrated to delivery a spray volume around 200 L/ha. Samples of reservoirs water were taken before and after sprays in order to evaluate the carrier quantity that not reaches the target. After that, the plants present at reservoirs were washed with distillated water until totally dyes removal deposited on the leaves. Plastic dishes containing 20 mL of distillated water were disposed in each experimental plot in order to check the spray efficacy and possible drift losses. Absorbance measures at 427 and 630 nm of wavelength were procedures... (Complete abstract, click electronic access below)
110

Efeito de pontas de pulverização e da palha de milheto na deposição da calda aplicada em pós- emergência inicial das plantas daninhas

Tokura, Luciene Kazue [UNESP] 19 January 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-01-19Bitstream added on 2014-06-13T19:40:03Z : No. of bitstreams: 1 tokura_lk_dr_botfca.pdf: 1103503 bytes, checksum: c13458e08e332be0ff5bbff0fa6c279c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve como objetivo avaliar o efeito de pontas de pulverização e da palha de milheto na deposição da calda aplicada sobre seis espécies de plantas daninhas. Foram utilizadas cinco pontas de pulverização (XR 11002; TJ60 11002; AI 110015; TJ60 11006 e TX-VK8), seis espécies de plantas daninhas (Ipomoea grandifolia; Euphorbia heterophylla; Commelina benghalensis; Bidens pilosa; Brachiaria plantaginea e Sida rhombifolia) e a condição sem e com presença de 5t.ha-1 de palha de milheto na deposição da calda aplicada. As pulverizações nas plântulas foram realizadas em pósemergência inicial (duas a quatro folhas) utilizando o corante FDC-1 Azul Brilhante (concentração de 0,8%), como solução traçadora. A pressão e o volume de aplicação (L.h-1) para cada ponta de pulverização foram realizados de acordo com as informações fornecidas pelo fabricante. No primeiro estudo foram realizados seis experimentos, sendo que 10 plântulas de cada espécie foram lavadas com 50mL de água destilada e a quantidade de solução tracadora estimada em densidade óptica de 630nm. No segundo estudo, cada plântula foi lavada com 25mL de água destilada permitindo estabelecer a quantidade de solução traçadora ou a solução de aplicação depositada em cada planta. Todos os experimentos foram realizados em delineamento inteiramente casualizado com quatro repetições e 10 plântulas de cada espécie em esquema fatorial 2x5 e as médias comparadas pelo teste t ao nível de 5% de probabilidade. No segundo estudo, os valores de deposição foram ajustados ao modelo de Gompertz. Em termos médios, a presença de 5t.ha-1 de palha de milheto reduziu em 20,12%, a 2 deposição de calda de aplicação na condição de pós-emergência inicial. A grande variabilidade dos depósitos unitários inviabiliza a comparação das pontas a partir de valores médios, modais ou medianos para... . / The aim of this reserch was to evaluate the effects of pearl millet on the deposition of application solution on six weed species. It were studyed five nozzle tip types (XR 11002; TJ60 11002; AI 110015; TJ60 11006 and TX-VK8), six weed species (Ipomoea grandifolia; Euphorbia heterophylla; Commelina benghalensis; Bidens pilosa; Brachiaria plantaginea and Sida rhombifolia) and the conditions without and with 5t.ha-1 of pearl millet mulch. The applications were carried out in early post-emergence (two and four leaves) using the dye FDC-1 (at the concentration of 0,8%) as a tracer. The pressure and the application volume (L.ha-1) were selected for each nozzle tip types according to the information of the dealers. In the first set of six experiments, ten plants of each species were 4 washed in destilled water and the amount of traces was stimated by the aplical density at 630nm. In the second set of experiments, each plant was washed in destilled water allowing to stablish the ammount of tracer or application solution deposited on each plant. All the experiments were designed completelly randomized with four replications and ten plants of each species per plot. In average, the presence of 5t.ha-1 of pearl millet mulch reduced in 20,12% the deposition in early post-emergence. The great variability of the unitary deposits makes unfeasible the comparison of the application technologies using mean, modal and median values. The most apropriate characteristics to compare of the quality of the applications accomplished with different points, correspond to the functions of non accumulated frequencies and the values of deposits associated to the lowest percentis of the accumulated frequencies. In the presence of mulch, the species of E. heterophylla, B. pilosa, B. plantaginea and S. rhombifolia were the most difficult be reached by the application droplets. For these species, the best results... (Complete abstract, click electronic address below).

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