Electrostatic phase separation: a review

The current understanding and developments in the electrostatic phase separation are reviewed. The literature covers predominantly two immiscible and inter-dispersed liquids following the last review on the topic some 15 years. Electrocoalescence kinetics and governing parameters, such as the applied field, liquid properties, drop shape and flow, are considered. The unfavorable effects, such as chain formation and partial coalescence, are discussed in detail. Moreover, the prospects of microfluidics platforms, non-uniform fields, coalescence on the dielectric surfaces to enhance the electrocoalescence rate are also considered. In addition to the electrocoalescence in water-in-oil emulsions the research in oil-in-oil coalescence is also discussed. Finally the studies in electrocoalescer development and commercial devices are also surveyed. The analysis of the literature reveals that the use of pulsed DC and AC electric fields is preferred over constant DC fields for efficient coalescence; but the selection of the optimum field frequency a priori is still not possible and requires further research. Some recent studies have helped to clarify important aspects of the process such as partial coalescence and drop–drop non-coalescence. On the other hand, some key phenomena such as thin film breakup and chain formation are still unclear. Some designs of inline electrocoalescers have recently been proposed; however with limited success: the inadequate knowledge of the underlying physics still prevents this technology from leaving the realm of empiricism and fully developing in one based on rigorous scientific methodology

Soybean seed treatment and coating with liquid and powdered polymer

Seed coating is a strong technology for soybean seeds, bringing great advantages to the farmers, allowing the application of polymers in an appropriate and necessary way to cover the seed. The objective of this research was to evaluate the efficiency of seed coating and the quality of soybean seeds treated with fungicide, insecticide, micronutrients and polymers, during six months of storage. Soybean seeds cultivar CD 209 were submitted to the following treatments: control, fungicide Fludioxonil + Metalaxyl - M (Maxim XL® - 100 mL.100 kg-1 seeds), insecticide Thiametoxan (Cruiser 350 FS® - 200 mL.100 kg-1 seeds), micronutrient ComoFix® (165 mL.100 kg-1 seeds - 24,75 mL Mo and 2,475 mL Co) and the mixture fungicide + insecticide + micronutrient. The same treatments were repeated using the liquid polymer Sepiret 9241 B Green (400 mL.100 kg-1 seed) and also powder polymer Sepiret Flo Branco (0,5 kg.100 kg-1 seeds) + colorant Corasem blue (50 mL.100 kg-1 seeds). Coating efficiency and physical and physiological seed quality in laboratory and seedling performance in the field were evaluated. It was concluded that: the use of polymer in seed coating presents seeds with good appearance, coloration, distribution and adherence of the products to the seed surface; uniformity of product distribution during seed treatment varies with the interaction between product and type of polymer used. Coating with liquid polymer is more efficient in soybean seeds. The use of polymers alters the hectolitre volumetric weight not affecting the physiologic quality. The powder polymer presents adverse latent effects after the storage of the seeds. The polymer should not be used separately in the treatment of seeds.O recobrimento de sementes é uma tecnologia que vêm se firmando cada vez mais, pois traz grandes vantagens ao agricultor, permitindo a aplicação de polímeros de forma adequada e precisa à semente. O objetivo deste trabalho foi avaliar a eficiência do recobrimento e a qualidade de sementes de soja tratadas com fungicida, inseticida, micronutrientes e polímeros líquido e em pó, durante seis meses de armazenamento. Sementes de soja do cultivar CD 209 foram submetidas aos seguintes tratamentos: testemunha, fungicida Fludioxonil + Metalaxyl M (Maxim XL® - 100 mL.100 kg-1 sementes), inseticida Thiametoxan (Cruiser 350 FS® - 200 mL.100 kg-1 sementes), micronutriente ComoFix® (165 mL.100 kg-1 sementes 24,75 mL Mo e 2,475 mL Co) e a mistura fungicida + inseticida + micronutriente. Os mesmos tratamentos foram repetidos utilizando o polímero líquido Sepiret 9241 B Green (400 mL.100 kg-1 semente) e também o polímero em pó Sepiret Flo Branco (0,5 kg.100 kg-1 sementes) + o corante Corasem azul (50 mL.100 kg-1 sementes). Foram avaliadas a eficiência do recobrimento, qualidade física e fisiológica das sementes em laboratório e o desempenho de plântulas em campo. Concluiu-se que: o uso de polímeros no recobrimento apresentou sementes com boa aparência, coloração, distribuição e aderência dos produtos á superfície das mesmas. A uniformidade de distribuição dos produtos no tratamento de sementes varia com a interação entre produto e tipo de polímero utilizado. O polímero líquido é mais eficiente no recobrimento de sementes de soja. O uso de polímeros altera o peso hectolítrico das sementes de soja, não afetando a qualidade fisiológica. O polímero em pó apresenta efeito latente adverso após o armazenamento das sementes. Os polímeros não devem ser utilizados isoladamente no tratamento de sementes

Use of continuous flowing blower with vertical air stream in barley, wheat and crimson clover seeds

The seed separation based on aerodynamical properties can be carried out to remove poor nourished or empty seeds and impurities. Air separation can be used alone or in conjunction with other separation as in air screen cleaner or gravity table separators. Among equipment there is the continuous flowing blower that uses only a vertical air stream to perform seed cleaning. So, the aim of this study was to evaluate the continuous seed blower with vertical air stream on barley, crimson clover and wheat seeds cleaning and quality upgrading. Seed samples of each specie were prepared and moisture content determined. The samples were blown at following air velocities: 6 m.s-1 to 14 m.s-1 (barley), 8 m.s-1 to 13 m.s-1 (crimson clover) and 8 m.s-1 to 13 m.s-1 (wheat), in 1 m.s-1 intervals. Physical purity, the thousand seed weight and the physiological quality (germination and vigor) were quantified. It was conclude that: 1 - it is possible to cleaning barley, crimson clover and wheat seeds and quality upgrading seed lots in a continuous flowing blower with vertical airstream; 2 - the air velocity 9, 10 and 11 m.s-1 where adequate to cleaning and quality ugrading barley, crimson clover and wheat seeds, respectively in the continuous flowing blower, considering seed physical purity, germination and vigor and acceptable seed discharge percentage; 3 - there is an horizontal air velocity gradient in the continuous flowing blower plastic tube; 4 - the voltage affect the air velocity in the plastic tube at low fan velocities in the continuous flowing blower with vertical airstream.A separação das sementes empregando como base as suas propriedades aerodinâmicas pode ser utilizada para remover sementes mal formadas e impurezas. A separação pelo ar pode ser utilizada isolada ou em conjunto com outras separações como no caso da máquina de ar e peneiras ou da mesa de gravidade, por exemplo. Dentre os equipamentos para separação utilizando apenas ar encontra-se o soprador contínuo com fluxo vertical de ar. Assim, o objetivo desse trabalho foi avaliar o soprador contínuo com fluxo vertical de ar na limpeza de sementes de cevada, trevo encarnado e trigo e no aprimoramento da qualidade fisiológica. Após a preparação das amostras de cada espécie, estas foram submetidas ao soprador regulado para velocidade do ar de 6 m.s-1 a 14 m.s-1 (cevada), 8 m.s-1 a 13 m.s-1 (trevo encarnado) e 8 m.s-1 a 13 m.s-1 (trigo), em intervalos regulares de 1 m.s-1. Avaliou-se a pureza física, o peso de mil sementes e a qualidade fisiológica. Concluiu-se que: 1 - é possível limpar sementes de cevada e trigo e aprimorar a qualidade dos lotes, utilizando soprador contínuo com fluxo vertical de ar; 2 - as velocidades do ar 9, 10 e 11 m.s-1 foram adequadas para a limpeza e aprimoramento da qualidade de sementes de cevada, trevo encarnado e trigo respectivamente em soprador continuo com fluxo vertical de ar, considerando a pureza física, germinação e o vigor e porcentagem de descarte de sementes aceitável; 3 - ocorre um gradiente horizontal da velocidade do ar no tubo plástico do soprador contínuo; 4 - a voltagem interfere na velocidade do ar no tubo plástico vertical em baixas velocidades do ventilador em soprador contínuo com fluxo vertical de ar

Systemic Uptake of Fluorescent Tracers by Soybean (Glycine max (L.) Merr.) Seed and Seedlings

Systemic seed treatment uptake was investigated in seeds and seedlings using fluorescent tracers to mimic systemic agrochemicals. Soybean was used as the model as soybean has the permeable seed coat characteristic to both charged and noncharged molecules. The purpose of the paper is to (1) screen 32 fluorescent tracers and then use optimal tracers for seed and seedling uptake, (2) investigate varietal differences in seed uptake, (3) examine the distribution of tracer uptake into 14-day-old seedlings, and (4) study the relationship between seed treatment lipophilicity, measured as log P on seed and root uptake. The major chemical families that displayed both seed and seedling uptake were coumarins and xanthenes. Seed uptake of coumarin 120 ranged from 1.1% to 4.8% of the applied seed treatment tracer from 15 yellow-seeded varieties. Rhodamine B, a xanthene compound uptake in seedlings, showed translocation from the applied seed treatment to all seedling tissues. Most of the tracer was measured in the hypocotyl and root, with lesser amounts in the epicotyl and true leaves. Log P is well documented in the literature to model systemic uptake by roots, but log P of the tracers were not related to seed uptake

Seed treatment and its impact on wheat crop yield potential

Abstract: In the sowing process, the technique of seed treatment may assist in maintaining crop yield potential. This present study aimed to assess how wheat seed treatment with two different sources of micronutrients, combined with fungicide + insecticide protective treatment and coating with liquid polymer, may impact its vegetative development and grain production. Wheat seeds of cultivar Tec Vigore were subjected to three different treatments using micronutrient containing zinc: no micronutrient, micronutrient 1 (1% Mn, 0.1% Mo, 10% Zn); micronutrient 2 (0.3% B, 0.3% Co; 3% Zn), where micronutrient treatments were combined with different protective treatments used for seed treatment: untreated seeds, polymer (Color seed He), fungicide (Vitavax® Thiram 200 SC) + insecticide (Cruiser® 350 FS) and combination of polymer + fungicide + insecticide. We assessed parameters related to crop development, such as seedling emergence, dry matter of root and shoot, tillers, and for physiological maturity, we assessed grain yield and hectoliter weight. Seed treatment with micronutrients, polymer, fungicide + insecticide and combinations thereof does not reduce emergence and may increase seedling stand, but without influencing wheat grain yield

Physiological performance of wheat seeds treated with micronutrients and protection products during storage

Abstract: Seeds with high quality are one of the important factors to consider in the crops establishment on field. Therefore, the physical and physiological quality of wheat seeds treated with mixes of micronutrients including zinc and protective products were aimed. The wheat seeds were analyzed in a factorial scheme 5x3x4, with five storage time: 0, 60, 120, 180 and 240 days; three micronutrients: micronutrients 1 (1% Mn; 0.1% Mo; 10% Zn); micronutrients 2 (0.3% B; 0.3% Co; 3% Zn) and no micronutrients, and four protective products: untreated seeds, polymer (Colorseed He), fungicide carboxin + thiram (Vitavax® Thiram 200 SC) + insecticide thiamethoxam (Cruiser® 350 FS) and polymer + fungicide + insecticide. After treatment, the seeds were stored under uncontrolled conditions for 240 days and at intervals of 60 days, the germination, accelerated aging and moisture content were determined. Wheat seeds untreated and treated with polymer have the best physiological performance during storage, regardless micronutrients treatments. The wheat seeds treated with carboxin + thiram + thiamethoxam and polymer + carboxin + thiram + thiamethoxam can be storage up to 120 days, under uncontrolled conditions, regardless micronutrients treatments. The seed treatment does not alter the moisture content of wheat seeds

Eficiência do recobrimento de sementes de soja em equipamento com sistema de aspersão Coating efficiency of soybean seeds in equipment with spray system

O trabalho tem o objetivo de avaliar o tratamento e o recobrimento de sementes de soja em um equipamento com sistema de aspersão da marca Grazmec Spray System®. O experimento foi realizado na Faculdade de Agronomia Eliseu Maciel (FAEM) da Universidade Federal de Pelotas, RS, Brasil. Os tratamentos foram: 1) testemunha (sem passagem pelo equipamento), 2) fungicida, 3) aminoácido, 4) polímero, 5) fungicida + aminoácido, 6) fungicida + inseticida, 7) fungicida + polímero, 8) fungicida + inseticida + polímero e 9) fungicida + aminoácido + inseticida, aplicados com o equipamento. Para avaliar o experimento, foram determinados o grau de umidade, emergência em campo, índice de velocidade de emergência, massa de 1000 sementes e intensidade de cobertura das sementes. De acordo com os resultados obtidos, verificou-se que o aumento no grau de umidade das sementes de soja tratadas e/ou recobertas com o equipamento de sistema de aspersão é inferior a 1%. A emergência de plântulas, índice de velocidade de emergência e a massa de 1000 sementes não foram afetados pelo tratamento e/ou recobrimento realizado com o sistema de aspersão. O uso de polímero melhora o recobrimento das sementes no equipamento com sistema de aspersão. Porém, o equipamento deve ser regulado a cada mudança de produto e/ou semente para que o recobrimento seja eficaz.The objective of this paper was to evaluate the treatment and coating of soybean seed using equipment with spray system Grazmec®. The experiment was carried out in the Faculdade de Agronomia Eliseu Maciel of the Universidade Federal de Pelotas, Rio Grande do Sul state, Brazil. The treatments were: 1) control (without equipment), 2) fungicide, 3) amino acid, 4) polymer, 5) fungicide + amino acid, 6) fungicide + insecticide, 7) fungicide + polymer, 8) fungicide + insecticide + polymer, 9) fungicide + amino acid + insecticide, all applied with the equipment. To evaluate the experiment the moisture content determination, field emergence, index of emergency speed, weight of 1000 seeds and intensity of coverage was carried out. The results showed that soybean seed treated and/or coated didn't reach more than 1% with the treatment. The field emergence, index of emergency speed and weight of 1000 seeds weren't affected by treatment and/or coating by spray system. The use of the polymer improves the seed coating when the spray system was used. However the equipment should be regulated when there is change of the product and/or seed to obtain an appropriate coating

Physiological performance of wheat seeds treated with micronutrients and protection products during storage

<div><p>Abstract: Seeds with high quality are one of the important factors to consider in the crops establishment on field. Therefore, the physical and physiological quality of wheat seeds treated with mixes of micronutrients including zinc and protective products were aimed. The wheat seeds were analyzed in a factorial scheme 5x3x4, with five storage time: 0, 60, 120, 180 and 240 days; three micronutrients: micronutrients 1 (1% Mn; 0.1% Mo; 10% Zn); micronutrients 2 (0.3% B; 0.3% Co; 3% Zn) and no micronutrients, and four protective products: untreated seeds, polymer (Colorseed He), fungicide carboxin + thiram (Vitavax® Thiram 200 SC) + insecticide thiamethoxam (Cruiser® 350 FS) and polymer + fungicide + insecticide. After treatment, the seeds were stored under uncontrolled conditions for 240 days and at intervals of 60 days, the germination, accelerated aging and moisture content were determined. Wheat seeds untreated and treated with polymer have the best physiological performance during storage, regardless micronutrients treatments. The wheat seeds treated with carboxin + thiram + thiamethoxam and polymer + carboxin + thiram + thiamethoxam can be storage up to 120 days, under uncontrolled conditions, regardless micronutrients treatments. The seed treatment does not alter the moisture content of wheat seeds.</p></div