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Using Trace Metals, Peroxide, Acid and Iodine Values to Characterize Oils Bleached Using Clays from Central and Eastern Uganda

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American Journal of Analytical Chemistry 2014年第17期5卷 1302-1312页

作者： Is’harq-Zubair Mukasa-Tebandeke Pancras John Mukasa Ssebuwufu Steven A. Nyanzi andreas schumann George W. Nyakairu Festo Lugolobi Department of Chemistry Makerere University Kampala Uganda Department of Geology Makerere University Kampala Uganda Department of Earth Sciences Wesleyan University Middletown CT USA

Bleaching of edible oils is known to alter the composition of oils as it removes impurities and certain food nutrients. The characteristics of bleached oil are strongly related to type bleaching medium, temperature at which bleaching is done and other factors. In this study, we compare peroxide, free fatty acid, acid and iodine values, copper and iron content of bleached and crude oils to establish the characteristics of edible oils bleached using smectite and kaolinite-rich clays. Oil industries spend large sums of money purchasing bleaching earths yet no country lacks natural clays which can be developed to bleach oils. In Uganda alone more than US$ 700,000 is spent every month yet many clay deposits are unexploited. In this study, we have documented trace metal composition, peroxide values, acid values, iodine values and free fatty acid content of bleached and unbleached cotton-seed and sunflower seed oils. The bleached oils were found to be fit for human use. Clays are either kaolinites or smectites, but the clays used to bleach edible oils are montmorillonites or bentonites. The decrease in content of iron in the bleached oils was highest for all oils bleached. The content of copper showed the smallest change. The content of copper in cotton oils decreased from 0.5 ppm to 0.15 ppm using Kajansi clay leached in 20% acid yet when Chelel clay leached under similar conditions was used decrease was from 0.5 to 0.1 ppm. The content of iron in sunflower oils bleached using Kajansi clay leached in 20% acid decreased from 1.6 to 0.2 ppm yet that bleached with Chelel clay under similar conditions decreased to 0.1 ppm. The acid values showed that the acidity in sunflower oils is largely due to oleic acid as the average value for acids is in the range close to oleic acid, cotton-seed oil corresponded to linoleic acid. The levels of free fatty acid were found to lie in range from 3.8 - 3.2 for all clays used showing no significant rise. The peroxide values of bleached oils

关键词： Bleached Oil Clays Trace Metals Peroxide Iodine

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机电一体化培训和教育中的电子移动学习课件开发(英文)

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计算机教育 2010年第9期 97-101页

作者： GLINIORZ Ralf KASSEL Stephan SCHMUCKER David schumann Christian-andreas Centre of New Course Facilities University of Applied Sciences ZwickauGermany Institute for Management and Information University of Applied Sciences ZwickauGermany

Knowledge is essential for the competitiveness of individuals as well as *** the application of the latest methodologies and technologies are utilized to support knowledge acquisition,warehousing,distribution,and *** and methods of web 2.0 are useful to support this ***,highly complex and very dynamic knowledge domains have to be accessible and applicable in the framework of learning network communities,including the stakeholders of training and *** for example is such an interdisciplinary,dynamic field of research and *** on intelligence,software,and hardware it is requiring special approaches for developing a courseware based learning and knowledge transfer *** defining the specifics of mechatronics education and postgraduate training in the context of e-education,the concepts of the development and utilization of mechatronic courseware can be deduced from e-learning 2.0 and mobile learning facilities,possibilities,and *** courseware will be developed by using authoring software and embedding the material into learning management systems with respect to general methods and rules of modern system and software *** an example,the courseware is used for vocational training and further education especially in cooperation networks of educational institutions and SME.

关键词： e-learning mechatronics m-learning web 2.0 eCommerce

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Adsorption Behavior of Acid-Leached Clays in Bleaching of Oil

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American Journal of Analytical Chemistry 2015年第6期6卷 495-512页

作者： I. Z. Mukasa-Tebandeke P. J. M. Ssebuwufu S. A. Nyanzi G. W. Nyakairu M. Ntale F. Lugolobi schumann andreas Department of Chemistry Makerere University Kampala Uganda Department of Earth Sciences Wesleyan University Middletown USA Department of Geology Makerere University Kampala Uganda

The available data have shown that acid-leached clays had sites for adsorption of impurities in oils. Data obtained on residual impurities in cotton and sunflower-seed oils bleached with the same clay materials produced linear Langmuir and Freundlich isotherms. The increase in constant, k with increase in both temperature of thermal activation and concentration of acid used to leach the clay, suggests that bleaching efficiency increased. The value of n decreased with increase in temperature of activation and concentration of acid used to leach the clay suggesting that bleaching capacity increased. The mineral compositions of the clays influenced their surface, structural and bleaching properties.

关键词： Adsorption Isotherms Bleaching Acid Activation Clays

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