• Title/Summary/Keyword: wetting index

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Soybean Oil-degrading Bacterial Cultures as a Potential for Control of Green Peach Aphids (Myzus persicae)

  • Kim, Seul-Ki;Kim, Seo-Ri;Choi, Min-Seok;Park, Chang-Eon;Kim, Young-Cheol;Kim, Kil-Yong;Whang, Kyung-Sook;Oh, Kyung-Taek;Kim, In-Seon
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1700-1703
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    • 2007
  • Microorganisms capable of degrading crude oil were isolated and grown in soybean oil as a sole carbon source. The microbial cultures were used to control green peach aphids in vitro. Approximately 60% mortality of aphids was observed when the cultures were applied alone onto aphids. To examine the cultures as a pesticide formulation mixture, the cultures were combined with a low dose of the insecticide imidacloprid (one-fourth dose of recommended field-application rate) and applied onto aphids. The cultures enhanced significantly the insecticidal effectiveness of imidacloprid, which was higher than imidacloprid alone applied at the low dose. The isolated microorganisms exhibited high emulsifying index values and decreased surface tension values after being grown in soybean oil media. GC/MS analyses showed that microorganisms degraded soybean oil to fatty acids. The cultures were suggested to play the roles of wetting, spreading, and sticking agents to improve the effectiveness of imidacloprid. This is the first report on the control of aphids by using oil-degrading microbial cultures.

A Study on the Applicability of $C_5$ Hydrofluoroether-based Formulated Cleaning Agents as CFC-Alternatives ($C_5$계 수소불화에테르를 기반으로 하는 배합 세정제의 CFC 대체세정제 적용 연구)

  • Min, Hye-Jin;Bae, Jae-Heum;Chang, Yoon-Sang
    • Clean Technology
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    • v.16 no.3
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    • pp.172-181
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    • 2010
  • Hydrofluoroethers (HFEs) with fluoride molecules in their structure which are evaluated as the third generation replacement alternatives to chlorofluorocarbons (CFCs) are known to be excellent for removal of nanoparticles and fluoride-type soils due to their low surface tension and high wetting index. In addition, HFEs have good physical properties with no flash point and excellent drying characteristics. But, HFEs also have shortcomings in that they are not effective for removal of organic soils due to their poor solubility in soil. In this study, $C_5$ HFE-based cleaning agents were formulated through addition of solvents such as isopropyl alcohol (IPA), ethyleneglycol monoether (EG), propyleneglycol monoethylether (PM) to HFE-7100 [$CF_3CF_2CF_2CF_2OCH_3$] or HFE-mec-f [$CF_3CHF=CF_2OCH_2CF_3$] with its maximum amount, respectively, in order to have no flash point for the safety in the working environment. These solvents are known to be excellent for dissolving organics in soil. Their physical properties and cleaning abilities for fluxes, water-insoluble cutting oils, and fluoride-type oils were evaluated and compared with those of other cleaning agents with single components. The experimental results show that the HFE-based formulated cleaning agents have various good physical properties which are almost similar to those of a single type of HFE cleaner. They show excellent cleaning ability for fluxes, water-insoluble cutting oils, and fluoride-type oils. These results indicate that the HFE-based formulated cleaning agents can be applicable to various industrial cleaning fields because of their good physical properties and cleaning abilities for various soils.