• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.247-250
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• 1992

Effects of free alkali and moisture on sucrose polyesters (SPE)-possible non calorie fat substitute-synthesis were investigated using a model system composed of sodium oleate, sucrose, potassium carbonate and methyl oleate. Trace amounts of free alkali in sodium oleate were found to interefere with SPE synthesis. When free alkali content in sodium oleate was varied gradually from 0% to 5%(w/w), the yield of SPE production was reduced from 92% to 45.5%. The moisture absorbed in sodium oleate, sucrose and potassium carbonate during storage also interefered with SPE synthesis. The yield (92%) of SPE production with dried ($105^{\circ}C$.6 hrs) reactants and catalysts was higher than that (89%) of SPE production with non-dried. Soybean oil fatty acid sodium soaps (FASS) not containing free alkali could be manufactured with slightly less than molar ratio of sodium hydroxide to soybean oil fatty acid methyl esters (FAME). Practically, 91.7% yield of soybean oil SPE production was outcomed by minimizing free alkali and moisture which were remaining in sucrose, potassium carbonate, soybean oil FASS and soybean oil FAME.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.633-637
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• 2007

Electroless plating of Co-alloy thin films as capping layers for Cu interconnection has been investigated using alkali-free precursors such as $(NH_4)_2Co(SO_4)_2{\cdot}6H_2O$, $(NH_4)_2WO_4$, $(NH_4)H_2PO_4$, etc. The characteristics of the Co-alloy thin films were discussed by analyses of the effects of pH, Co-precursor concentration, and deposition temperature on the thickness and surface morphology of the films. The thickness of the Co-alloy thin films increased with increasing pH, Co-precursor concentration, and deposition temperature, similarly to the results of electroless plating of Co-alloy thin films using alkali-containing chemicals. The SEM images of the surface of the Co-alloy thin films showed that the proper ranges of pH and deposition temperature were 8.5~9.5 and $75{\sim}85^{\circ}C$, respectively. This work found a feasibility that Co-alloy thin films as capping layers for Cu interconnection could be electroless plated using alkali-free chemicals.