Determinação da deriva da mistura 2,4-D e glyphosate com diferentes pontas de pulverização e adjuvantes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização funcional de adjuvantes em soluções aquosas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tamanho de gotas de pontas de pulverização em diferentes condições operacionais por meio da técnica de difração do raio laser

The present study aimed to evaluate the droplet spectrum of hydraulic nozzles, under different pressures and spray liquid compositions, using a laser particle size analyzer. In a completely randomized design, two air induction twin flat-fan nozzles (AD-IA/D 11002 and AD-IA/D11004) and two hollow-cone nozzles (MAG - 2 and MAG - 4) were evaluated, in factorial design 3 x 2: tree spray pressures (207, 276 and 345 kPa for twin flat-fan nozzles, and 414, 483 and 552 kPa for cone nozzles); and two spray liquid compositions (water and water plus phosphatydilcoline + propionic acid adjuvant). The addition of adjuvant reduced the volume median diameter for the AD-IA/D 11002 and 11004 nozzles; however it had an opposite effect with the MAG - 4 nozzles and not changed with the MAG - 2 nozzles. In adverse weather conditions, it is not recommended the use of hollow cone spray nozzle, even with the addition of adjuvant tested because of the high risk potential of drift.

Development and characterization of biocompatible isotropic and anisotropic oil-in-water colloidal dispersions as a new delivery system for methyl dihydrojasmonate antitumor drug

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualidade da pulverização em volume reduzido para o controle do bicho-mineiro Leucoptera coffeella (Guérin-Mèneville & Perrottet, 1842) (Lepidoptera: Lyonetiidae)

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Desenvolvimento e avaliação das atividades antioxidante e despigmentante in vitro de emulsões múltiplas a/o/a contendo dipalmitato kójico

Currently, there has been a growing concern for men and women with the appearance of the face and body, driven primarily by aesthetic standards set by the media. For this, the pharmaceutical and cosmetic industries have conducted numerous research projects aiming at the development of formulations that mitigate the aging and some skin disorders such as hipercromies. One of the most frequent pathologies of skin is melasma, a manifestation of hyperpigmentation caused by hipermelanogenesis symmetrical and progressive, caused usually by hormonal irregularities, exposure to sunlight and genetic factors. In addition to sunscreen, the treatment is indicated the use of depigmenting substances, among them the kojic dipalmitate (DK), which is cleaved into kojic acid (5- hydroxy-2-hydroxy-methyl-4H-piran-4-one) by esterase after absorption by the skin cells. The kojic acid inhibits the action of tyrosinase as a chelator of ions and promotes the reduction of eumelanin and its precursor monomer. To promote a controlled release and improve the stability of the system, the DK can be incorporated into multiple emulsions, that is, complex systems composed of two emulsifications, where the two types of emulsions (W/O and O/W or O/W and W/O) exist simultaneously, forming emulsions of type W/O/W or O/W/O. This work aimed to incorporate the DK in emulsion W/O/W, physical-chemical systems obtained and to evaluate the antioxidant and depigmenting action in vitro of the developed formulations. The physico-chemical characterization was performed by microscopic analysis, quantification and size distribution, determination of pH, conductivity, zeta potential and bioadhesive test of the formulations. The droplet size in accordance with the use of light microscopy and dynamic light scattering is approximately 1μm. The pH, electrical conductivity and bioadhesion have not changed with the addition... (Complete abstract click electronic access below)

Spray adjuvant characteristics affecting agricultural spraying drift

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Structural characterization and in vitro antioxidant activity of kojic dipalmitate loaded W/O/W multiple emulsions intended for skin disorders

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

Development, characterization, and in vitro biological performance of fluconazole-loaded microemulsions for the topical treatment of cutaneous leishmaniasis

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

Oil-in-water biocompatible microemulsion as a carrier for the antitumor drug compound methyl dihydrojasmonate

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Development and characterization of a biocompatible soybean oil-based microemulsion for the delivery of poorly water-soluble drugs

The aim of this work was the development and characterization of a biocompatible microemulsion (ME) containing soybean oil (O), phosphatidylcholine/sodium oleate/Eumulgin®HRE40 as the surfactant mixture (S) and water or buffer solution as the aqueous phase (W), for oral delivery of the poorly water-soluble drugs sulfamerazine (SMR) and indomethacin (INM). A wide range of combinations to obtain clear oil-in-water (o/w) ME was observed from pseudo-ternary phase diagrams, which was greater after the incorporation of both drugs, suggesting that they acted as stabilizers. Drug partition studies indicated a lower affinity of the drugs for the oil domain when they were ionized and with increased temperature, explained by the fact that both drugs were introduced inside the oil domain, determined by nuclear magnetic resonance. High concentrations of SMR and INM were able to be incorporated (22.0 and 62.3 mg/mL, respectively). The ME obtained presented an average droplet size of 100 nm and a negative surface charge. A significant increase in the release of SMR was observed with the ME with the highest percentage of O, because of the solubilizing properties of the ME. Also, a small retention effect was observed for INM, which may be explained by the differences in the partitioning properties of the drugs. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3535-3543, 2015.

Caracterização física e química e potencial de deriva de caldas contendo surfatantes em pulverizações agrícolas

The aim of this work was to evaluate the effect of the addition of different surfactants in physical and chemical properties of spray solutions, droplets spectra and drift potential on agricultural spraying. The surfactants and concentrations (v v-1) were: Haiten (0.1%), Antideriva and Intec (0.05% and 0.1%). The following characteristics were analyzed: surface tension, viscosity, density and electric conductivity. The droplet size spectrum was determined by a laser particle analyzer (Mastersizer S®, version 2.15) including measurements of volume medium diameter (VMD), the percent of droplets below 50 and 100 μm (V50 e V100) and index span. In order to estimate the drift potential, a series of wind tunnel tests were performed with a Teejet XR 8003 flat fan nozzle at 200 kPa (medium droplets) used to apply the spray solutions containing water, the adjuvants and a food color dye (Brilliant blue FD & C no 1) at 0,6% m v-1. The drift was collected on nylon strips transversally fixed along the tunnel at different distances from the nozzle and different high from the bottom part of the tunnel. Drift deposits were evaluated by spectrophotometry. The results showed that the addition of adjuvants changed physical and chemical properties of spray solutions in different magnitudes according to the surfactant. Surfactants changed the droplet spectrum and drift potential, indicating that higher VMD and smaller V100 induced higher percentage of drift.

Babassu Nanoemulsions Have Physical and Chemical Stability

Babassu is considered one of the greatest native resources in the world and its oil is used in body and hair formulations. The aim of this study was to evaluate the short-term stability in oil-in-water (O/W) nanoemulsions containing babassu oil prepared by emulsification phase inversion submitted to the centrifugation, thermal stress, and heating/cooling cycle tests. The formulations showed no change compared to the droplet size, polydispersity index, pH, and electrical conductivity values after thermal stress and heating/cooling cycle tests. Based on these results, the nanoemulsions obtained can be considered as promising disperse systems for pharmaceutical and cosmetic applications.

Numerical simulation of an ethanol turbulent spray flame with RANS and diffusion combustion model

A detailed numerical simulation of ethanol turbulent spray combustion on a rounded jet flame is pre- sented in this article. The focus is to propose a robust mathematical model with relatively low complexity sub- models to reproduce the main characteristics of the cou- pling between both phases, such as the turbulence modulation, turbulent droplets dissipation, and evaporative cooling effect. A RANS turbulent model is implemented. Special features of the model include an Eulerian– Lagrangian procedure under a fully two-way coupling and a modified flame sheet model with a joint mixture fraction– enthalpy b -PDF. Reasonable agreement between measured and computed mean profiles of temperature of the gas phase and droplet size distributions is achieved. Deviations found between measured and predicted mean velocity profiles are attributed to the turbulent combustion modeling adopted

Grenzflächenspannung und Morphologie fließender zweiphasiger Polymermischungen

In der vorliegenden Arbeit wurde die Morphologie von zweiphasigen Polymermischungen unter Scherung in situ mit Hilfe einer Kombination aus optischer Scherzelle, Durchlichtmikroskop und computergestützten CCD-Kamera untersucht. Als Modellblends dienten die unverträglichen, bei Raumtemperatur flüssigen Polymersysteme Polyisobutylen (PIB)/Polydimethylsiloxan (PDMS) (I) und Poly(dimethyl-co-methylphenyl)siloxan/PDMS (II). Alle Komponenten verhalten sich bei den verwendeten Scherraten newtonisch.Eine der wichtigsten Einflussgrößen für die Blendmorphologie ist die Grenzflächenspannung gamma 12. Sie wurde für I und II mit Hilfe der Methode der Tropfenrelaxation (dynamisch) als Funktion der Zeit bestimmt. Diese Methode erlaubt die Messung von gamma 12 für Tropfen der Phase A in B sowie von Tropfen B in A. Bei der Methode des hängenden Tropfens (statisch) muss der Tropfen aus der Phase mit der höheren Dichte bestehen. Wo der Vergleich der beiden Methoden möglich ist, stimmen die Ergebnisse für beide Systeme sehr gut überein. Bei II sind die aus der Tropfenrelaxation erhaltenen gamma 12-Werte der beiden komplementären Zusammensetzungen im Rahmen des Fehlers gleich, bei I zeigt ein PIB-Tropfen in PDMS einen um 40 % niedrigeren Wert als ein PDMS-Tropfen in PIB, dies wird auf die Diffusion von kurzkettigen Anteilen des PDMS in die Grenzschicht zurückgeführt. Die Grenzflächenspannung hängt also unter Umständen auch bei binären Systemen deutlich von der Zusammensetzung ab.Für II wurde die Blendmorphologie über den gesamten Zusammensetzungsbereich untersucht. Die häufig beobachteten cokontinuierlichen Strukturen treten bei keiner Zusammensetzung auf. Die Phaseninversion erkennt man in einer sprunghaften Änderung der Tropfengröße zwischen phiPDMS <= 0,400 und 0,500; zudem lässt sich die Zeitabhängigkeit der Radien durch Auftragung gegen das Produkt aus der Deformation und dem Quadrat des Volumenbruchs der Tropfenphase für 0 <= phiPDMS <= 0,400 sowie 0,500 <= phiPDMS <= 1 normieren. Für I und II wurde die Morphologieentwicklung bei 25 °C nach Vorscherung bei 100 bzw. 50 s-1 und anschließendem Sprung der Scherrate auf deutlich niedrigere Werte als Funktion der Zeit verfolgt. Hierbei erhält man bei genügend langer Messdauer (mindestens 200 000-300 000 Schereinheiten) konstante Tropfengrößen. Zum einen handelt es sich dabei um pseudo-stationäre Werte, die nur durch Koaleszenz bestimmt sind, zum anderen um echte stationäre Radien, die durch gleichzeitig ablaufende Koaleszenz und Zerteilung entstehen. Für I liegen die stationären Mittelwerte auf der Zerteilungskurve, für II hingegen auf der Koaleszenzkurve.Der Einfluss eines grenzflächenwirksamen Additivs wurde anhand von I durch Zugabe des Blockcopolymer PIB-b-PDMS zu PIB untersucht. Der Vergleich des zeitlichen Verlaufs von gamma 12 mit der Morphologieentwicklung zeigt, dass das Additiv eine Stabilisierung der feinen Tropfen/Matrix-Struktur des Blends durch Hinderung der Koaleszenz und nicht durch Reduktion der Grenzflächenspannung bewirkt.