• Applied Biological Chemistry
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• v.36 no.4
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• pp.284-289
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• 1993

The effect of oil refining processes-degumming, alkali-refining, bleaching and deodorizing-on oil characteristics and oxidation stability of sesame oil were investigated. The colors(L, a, b) of samples were markedly changed and their peroxide and acid values were decreased, while the other characteristics of samples were not changed during refining stages. The L values of alkali-refined, bleached and deodorized sesame oils were largely decreased and their a values were increased due to browning reaction during the storage at $70^{\circ}C$. The colors of crude and degmmed sesame oils were very stable and their peroxide, free fatty acid and conjugated dienoic acid values were slowly increased. Volatile carbonyl compounds formed by oxidation were increased during the storage at $70^{\circ}C$. The results indicated that refining processes did not affect the sesame oil characteristics but decreased the oxidation stability of sesame oil.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.868-872
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• 1988

The oxidation behaviour of Pinenut(Pinus Koraiensis S & Z) oil during storage were studied. And the oxidative stability of different oil samples by refining stage were also measured. The oil in whole pinenut or mashed pinenut was very stable during the storage at $35^{\circ}C$ for 10 weeks however, the oxidation rate was enhanced when pinenut oil was extracted and isolated from nut cake. On the other hand, crude oil was most stable and the highly purified pinenut oil was least stable, with other samples being intermediate in stability. The changes of fatty acid composition of various pinenut oil samples during storage were also discussed.

• Korean Journal of Metals and Materials
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• v.47 no.3
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• pp.188-194
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• 2009

Recently, new extraction technology for manganese nodule has been developed as alternative noble metallic resources. It is important to understand thermodynamic behaviors of phosphorus in low basic slag system from the viewpoint of the refining processing optimization. Thermodynamic behaviors of phosphorus in the $FeO-MnO-CaO-SiO_2-MgO_{satd.}$ slag system were investigated at 1723 K with various oxygen potential and slag composition of low basicity. The experimental results for dependence of phosphorus on oxygen potential and slag basicity indicated that the dissolution mechanism of phosphorus into slag of low basicity could be derived as follows; $[P]+5/4O_2+(O^{2-})=({PO_{3.5}}^{2-})$ Present experimental results implied that stability of phosphorus in slag would be depended on both of $O^{2-}$ (basicity) and content of $Ca^{2+}$ in molten slag. The thermodynamic effect of FeO, MnO and $Na_2O$ on low basicity on phosphate capacity was discussed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.47-56
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• 1999

New rolling speed prediction model has been developed for the precise presetting rolling speed of each finishing mill stand in the tandem hot strip mill. Those factors such as neutral point, work roll diameter, rolling torque, friction coefficient, bite angle and the thickness at each side of entry and deliver of the rolls were taken into account. To consider width effect on forward slip, calibration factors obtained from rolling torque has been added to new prediction model and refining method has also been developed to reduce the speed unbalance between adjacent stands. The application of the new model showed a good agreement in rolling speeds between the predictions and the actual measurements, and the standard deviation of prediction error has also been significantly reduced.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.275-281
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• 2017

This study is to investigate experimentally the effect of refining of fly ash (FA) on the engineering properties of the cement mortar. Five different FAs are used including raw fly ash, refined fly ash, reject ash and their two different combinations. The cement mortars are fabricated with 1:1(binder to fine aggregate), 1 : 3 and 1 : 5 respectively, which are replaced 30% of FA by cement. Test results, indicated that, the flow of Ra showed lower flowability than Rf at all mixing ratios. Also in the case of Rj, it was expected to show low fluidity, but it showed flowability equal to or higher than Rf. Air contents are all formulations except Rf and Rj did not satisfy the target range. Using Ra, the refining process shows an air amount about 41% lower than Rf, in the case of Rj, it showed about 19% higher air content than Rf due to porous foreign matters inside the mortar. Compressive strength was in the early days 3 and 7, the strength was lower than that of Plain's OPC, after 28 days Rf exerts higher strength than other FAs, it was confirmed that higher strength than OPC can be secured at a mixing ratio of 1: 1 and 1: 3. For frost resistance, the use of unrefined FA resulted in decrease of frost resistance sharply due to loss of air content by the use of unrefined FA. Therefore, it is considered that the use of high quality FA through refining process will contribute positively to the economical formulation of concrete and the stability of the structure.