Tensão superficial estática de soluções aquosas com óleos minerais e vegetais utilizados na agricultura

O trabalho teve como objetivo avaliar a tensão superficial estática de soluções aquosas com formulações de óleos minerais e vegetais emulsionáveis utilizados como adjuvantes na agricultura. Os óleos minerais e vegetais, quando adicionados aos produtos fitossanitários, podem imprimir características desejáveis à calda de pulverização, como reduzir a tensão superficial em soluções aquosas, possibilitar maior contato da calda com a superfície vegetal ou reduzir o potencial de deriva durante as pulverizações. Foram testados os seguintes produtos comerciais: óleos minerais (Assist, Attach, Dytrol, Iharol, Mineral Oil, Spinner, Sunspray-E e Triona) e óleos vegetais (Agrex'oil Vegetal, Crop Oil, Natur'l Óleo, Óleo Vegetal Nortox e Veget Oil), todos com registro de uso na agricultura. A tensão superficial das soluções aquosas foi avaliada em 11 concentrações para cada produto (0,025; 0,05; 0,1; 0,25; 0,5; 0,75; 1,0; 1,5; 2,0; 2,5 e 3,0% v/v). Essa propriedade dos óleos minerais e dos óleos vegetais foi estimada medindo-se a massa das gotas formadas na extremidade de uma bureta. Ao conjunto de dados obtidos para cada produto, na avaliação da tensão superficial, foram determinadas as análises de variância e de regressão, ajustando-se os dados ao Modelo de Mitscherlich. Entre os óleos minerais, destacaram-se os produtos: Assist, Dytrol, Iharol e Mineral Oil por apresentarem as menores tensões superficiais mínimas estimadas pelo Modelo, respectivamente, 29,255; 28,442; 26,097 e 28,584 mN m-1. Os óleos vegetais que apresentaram os menores valores de tensão superficial mínima estimados pelo Modelo, foram: Agrex' oil Vegetal (27,716 mN m-1), Natur'l óleo (28,216 mN m-1), Veget Oil (27,308 mN m-1) e Crop Oil (29,964 mN m-1).

Efeitos de óleos nas características físicas e químicas da calda de aplicação e na ação da atrazina

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento de um sistema de análise de imagem para quantificação do tamanho e distribuição de partículas de desgaste

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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)

Eficácia de óleos minerais aplicados como adjuvantes auxiliando na selitividade de herbicidas na cultura de cana-de-açúcar

Pós-graduação em Agronomia - FEIS

El agua regenerada y la producción de biocombustibles

[ES] La Jatropha curcas L., una especie tóxica que no interfiere en la cadena alimentaria, produce biodiesel de mejor calidad ambiental que los aceites de origen mineral pero, para su cultivo, se emplean recursos limitados, fundamentalmente agua y suelo. Por tanto, en las zonas áridas es necesario cultivarla en condiciones intensivas, regando con aguas regeneradas y disminuyendo los costes productivos. Para optimizar el consumo del agua se ha empleado el riego alterno de raíces, que mantiene seca una parte del sistema obteniéndose menos frutos/racimo pero más racimos fértiles/árbol, lo que permitirá estrechar el marco de plantación, una de las pocas opciones para mejorar su rentabilidad pues la producción por árbol es muy estable

Elevated interleukin 6 is induced by prostaglandin E2 in a murine model of inflammation: possible role of cyclooxygenase-2.

Injection of mineral oils such as pristane into the peritoneal cavities of BALB/c mice results in a chronic peritonitis associated with high tissue levels of interleukin 6 (IL-6). Here we show that increased prostaglandin E2 (PGE2) synthesis causes induction of IL-6 and that expression of an inducible cyclooxygenase, Cox-2, may mediate this process. Levels of both PGE2 and IL-6 are elevated in inflammatory exudates from pristane-treated mice compared with lavage samples from untreated mice. The Cox-2 gene is induced in the peritoneal macrophage fraction isolated from the mice. A cause and effect relationship between increased macrophage PGE2 and IL-6 production is shown in vitro. When peritoneal macrophages are activated with an inflammatory stimulus (polymerized albumin), the Cox-2 gene is induced and secretion of PGE2 and IL-6 increases, with elevated PGE2 appearing before IL-6. Cotreatment with 1 microM indomethacin inhibits PGE2 production by the cells and reduces the induction of IL-6 mRNA but has no effect on Cox-2 mRNA, consistent with the fact that the drug inhibits catalytic activity of the cyclooxygenase but does not affect expression of the gene. Addition of exogenous PGE2 to macrophages induces IL-6 protein and mRNA synthesis, indicating that the eicosanoid stimulates IL-6 production at the level of gene expression. PGE2-stimulated IL-6 production is unaffected by addition of indomethacin. Taken together with the earlier finding that indomethacin diminishes the elevation of IL-6 in pristane-treated mice, the results show that PGE2 can induce IL-6 production in vivo and implicate expression of the Cox-2 gene in the regulation of this cytokine.

Power plant chemistry ... y Augustus H. Gill ...

Formerly published under the title of Engine room chemistry.

Desenvolvimento e avaliação tribológica de emulsão O/A a partir de óleo vegetal epoxidado para aplicação em fluídos de corte

The cutting fluids are lubricants used in machining processes, because they present many benefits for different processes. They have many functions, such as lubrication, cooling, improvement in surface finishing, besides they decreases the tool wear and protect it against corrosion. Therefore due to new environment laws and demand to green products, new cutting fluids must be development. These shall be biodegradable, non-toxic, safety for environment and operator healthy. Thus, vegetable oils are a good option to solve this problem, replacing the mineral oils. In this context, this work aimed to develop an emulsion cutting fluid from epoxidized vegetable oil, promoting better lubrication and cooling in machining processes, besides being environment friendly. The methodology was divided in five steps: first one was the biolubricant synthesis by epoxidation reaction. Following this, the biolubricant was characterized in terms of density, acidity, iodo index, oxirane index, viscosity, thermal stability and chemical composition. The third step was to develop an emulsion O/A with different oil concentration (10, 20 and 25%) and surfactant concentration (1, 2.5 and 5%). Also, emulsion stability was studied. The emulsion tribological performance were carried out in HFRR (High Frequency Reciprocating Rig), it consists in ball-disc contact. Results showed that the vegetable based lubricant may be synthesized by epoxidationreaction, the spectra showed that there was 100% conversion of the epoxy rings unsaturations. In regard the tribological assessment is observed that the percentage of oil present in the emulsion directly influenced the film formation and coefficient of friction for higher concentrations the film formation process is slow and unstable, and the coefficient of friction. The high concentrations of surfactants have not improved the emulsions tribological performance. The best performance in friction reduction was observed to emulsion with 10% of oil and 5% of surfactant, its average wear scar was 202 μm.

Analytical strategies for the early quality and safety assurance in the global feed chain. Approaches for nitrogen adulterants in soybean meal and mineral and transformer oils in vegetable oils.

In the past decade, several major food safety crises originated from problems with feed. Consequently, there is an urgent need for early detection of fraudulent adulteration and contamination in the feed chain. Strategies are presented for two specific cases, viz. adulterations of (i) soybean meal with melamine and other types of adulterants/contaminants and (ii) vegetable oils with mineral oil, transformer oil or other oils. These strategies comprise screening at the feed mill or port of entry with non-destructive spectroscopic methods (NIRS and Raman), followed by post-screening and confirmation in the laboratory with MS-based methods. The spectroscopic techniques are suitable for on-site and on-line applications. Currently they are suited to detect fraudulent adulteration at relatively high levels but not to detect low level contamination. The potential use of the strategies for non-targeted analysis is demonstrated.

Assessing the energy efficiency of gear oils via the FZG test machine

Energy efficient lubricants are becoming increasingly popular. This is due to a global increase in environmental awareness combined with the potential of reducing operating costs. A new test method of evaluating the energy efficiency of gear oils has been described in this report. The method involves measuring the power required by an FZG test rig to run while using a particular test lubricant. For each oil that was being evaluated, the rig was run for 10 minutes at a load stage of 10. Six extreme pressure (EP) industrial gear oils of mineral base were tested. The difference in power requirements between the best and the worst performing oils was 2.77 and 3.24 kW, respectively. This equates to a 14.6% reduction in power, a significant amount if considered in relation to a high powered industrial machine. The oils of superior performance were noticed to run at reduced temperatures. They were also more expensive than the other products of lesser performance.

Evaluation of the biodegradation of different types of lubricant oils in liquid medium

Avaliação da Biodegradação de Diferentes Tipos de Óleo Lubrificante em Meio Aquoso pela Norma Técnica L6.350 (CETESB, 1990), utiliza-se o processo respirométrico de Bartha e Pramer para acompanhar a biodegradação de diferentes tipos de óleo lubrificante automotivo adaptado ao meio aquoso. Para realização do experimento foram preparados um inóculo base e, posteriormente, um inóculo aquoso. Quatro tratamentos foram realizados em dois experimentos consecutivos: T1 (controle); T2 (óleo semi-sintético); T3 (óleo mineral); T4 (óleo usado). Dentre os resultados, obteve-se a seguinte ordem decrescente na produção de CO2 nos respirômetros: T4 > T2 > T3 > T1. Assim, o óleo lubrificante usado surgiu com maior biodegradabilidade, seguido do semisintético e do óleo mineral. Observou-se também que o lubrificante mineral apresentou maior período de adaptação comparado ao semisintético.

Biodegradation and toxicological evaluation of lubricant oils

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influence of organic and mineral soil fertilization on essential oil of Spilanthes oleracea cv. Jambuarana

In the present study, the composition of essential oil of leaves and inflorescences of jambu (Spilanthes oleracea. Jambuarana), under organic manuring and mineral fertilization, was stuhed. Jambu plants show important chemical properties and their production has been addressed for the extraction of the essential oils for cosmetics industries, due to their pharmacolopcal properties. The experimental area of treatments contained urea as mineral fertilizer (120 g m2), applied twice and organic fertilizer (8 kg m2), applied at the planting. Jambu leaves and flowers were harvested twice: the first at 90 days after seedling transplantation and at the opening of the flower buds. Branches were cut at 7 cm from the soil, thus new branches can bud for the accomplishment of the second crop which happened 40 days after the re-budhng. The essential oil was analyzed by gas chromatography coupled with mass-spectrometry. According to our results the most representative compounds were trans-caryophyllene, germacrene-D, 1-dodecene, spathulenol and spilanthol (a compound presenting anesthetic properties) occurring in inflorescences. Fertilization procedure does not affect the content and the quality of the essential oil in Jambu plants. © 2012 Academic Journals Inc.