Pulverização eletrostática e assistência de ar no tratamento fitossanitário na cultura do algodoeiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito de óleos minerais e vegetais nas propriedades físico-químicas das caldas de pulverização e suas interações com superfícies foliares

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Depósito da pulverização e controle de Tetranychus urticae Koch em crisântemo de corte com pulverizador assistido por ar e eletrostático

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Efeitos da congelação lenta e vitrificação sobre a qualidade e viabilidade de embriões bovinos produzidos in vitro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da utilização de antioxidante no diluidor para a criopreservação de sêmen bovino avaliado através de testes complementares, inseminação artificial e fecundação in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação dos efeitos da inibição da maturação nuclear e de antioxidantes sobre a maturação oocitária, fecundação e desenvolvimento embrionário bovino in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Produção in vitro de embriões bovinos cultivados em duas atmosferas gasosas utilizando diferentes sistemas de tamponamento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Investigação de injetores tipo y e efervescentes para a atomizacão da mistura de glicerina e etanol

Pós-graduação em Engenharia Mecânica - FEG

Desenvolvimento e caracterização físico-química e biofarmacêutica de nano e microemulsões lipídicas de uso intravenoso contendo metildiidrojasmonato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Expressão de fatores relacionados à morte celular programada em embriões bovinos infectados com BHV-5

Pós-graduação em Microbiologia - IBILCE

Potential of adjuvants to reduce drift in agricultural spraying

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The seasonal and ovarian status effects on in vitro production of domestic cat embryos between Equator and Tropic of Capricorn

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of adjuvants on the amount of air included in droplets generated by spray nozzles

The air included in droplets generated by spray nozzles directly int0erferes in transport, deposition and retention of the droplets after its impact on the target. The objective of this study was to analyze the interference of adjuvants in the amount of air included in droplets generated by spray nozzles. The treatments were composed by four spray solutions containing mineral oil, vegetable oil, surfactant and water, and three spray nozzles, two air induction type and one pre-orifice. The air included was calculated by the difference between the volume of spray mix (air plus liquid) and only the liquid, which was made by means of sprayed samples captured in a funnel and collected in a graduated cylinder. The surface tension was estimated by the gravimetric method using a precision scale and a graduated pipette. The surfactant provided the largest percentage of air included in the spray. For the surface tension, the mineral oil and the surfactant had the lowest values. It was concluded that the use of adjuvants had a direct influence on the percentage of air included. In addition, products with greater ability to reduce surface tension and to form homogeneous solutions provided the increase in the percentage of air included in the droplet.

Adjuvantes na deriva de 2,4-D + glyphosate em condições de campo

The aim of the research was to evaluate the effect of adjuvants on the spray drift applications from mixture of 2,4-D + glyphosate. The trial was carried out in field conditions in a completely randomized design. The treatments corresponded to solutions containing mixture of the herbicides 2,4-D + glyphosate (670 and 1068g ha-1, respectively) adding the adjuvants (v v-1): mineral oil (0.5%); anti-drift agent (0.09%); spreader-sticker A (0.1%); liquid fertilizer (0.05%); spreader-sticker B (0.25%); and only herbicides without adjuvantes (control). Nylon strings were used to drift determination outside the application area (1, 5, 10, 20, 50, 100 and 200 m away) with 4 replications and six foam cylinders placed on the boom of the sprayer were used to collect the droplets subject to drift. The applications were performed simultaneously, using a specific salt tracer for each spray solution to quantify the deposits by spectrophotometer. It was not possible to verify effect of the adjuvants on drift at different distances of the application area. Based on droplets collected above the boom spray, it was found that susceptibility to drift was lower with the mineral oil and the anti-drift agent. The drift risk was higher with the liquid fertilizer and the spreader-sticker B.

Uma abordagem diferente na estatística do experimento Millikan

The classic Millikan experiment to determine the electron charge is very interesting from the point of view of statistics of experimental measurements. In a physics laboratory it is suggested to divide the obtained values of the electric charge by the value of an electron charge, and it is possible to experimentally establish that the oil droplets carry integer numbers of electrons. This work presents a new statistical algorithm for the treatment of measurements and for determining the best value of the electron charge in a Millikan experiment.