• Clean Technology
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• v.16 no.3
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• pp.220-228
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• 2010

Four Keggin-type heteropolyacids, $H_nXM_{12}O_{40}$(X = P and Si, M = W and Mo) that were substituted with heteroatom and polyatom were applied to the dehydration reaction of fructose to 5-hydroxymethylfurfural (HMF). The results showed that the acid became stronger when the heteroatom and polyatom were substituted with P and W than the cases of Si and Mo, respectively. However, the amount of acidic sites increased with the decrease in the acid strength, resulting in the change of the catalytic activity of heteropolyacids in the dehydration reaction. The experimental results revealed that four different heteropolyacids produced similar amounts of HMF via the dehydration reaction of fructose due to the counterbalancing effect between the amount of active sites, which is related to the catalytic activity of heteropolyacids, and the softness of polyanion. In addition, it was observed that the prepared heteropolyacids showed good structural stability after heat treatment at $200^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.245-252
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• 2010

The objective of this study was to obtain the basic informations on variability of germplasm and cultivation practice for the production of biodiesel in sunflower. A total of 275 accessions obtained from the National Agrobiodiversity Center (34 landraces from Korea, 219 and 22 introductions from America and other countries, respectively) were screened to evaluate variations of seed characteristics, oil content and fatty acid composition. Seed types were classified into 4 types (broad ovoid, narrow ovoid, rounded and elongated). The broad ovoid type was the highest proportion of 40.4%, while the elongated type was the lowest proportion of 5.0% among accessions. Also, the seed colors were classified into 4 colors (gray, brown, black and white). Gray and brown seed color showed the highest distribution and white seed color showed the lowest among accessions, respectively. Hundred and one liter seed weight ranged 2.9~15.5g and 178~439g with averages of 6.3g and 322.0g, respectively. Oil content ranged from 11.7% to 45.6% with an average of 25.5%. The frequency distribution of oil content showed the highest in range of 22~28% and the lowest in range of over 40%. Three promising accessions with higher oil content than 40.0% were IT031967, IT031970 and IT031965 introduced from America. Palmitic and stearic acid contents, saturated fatty acid, ranged 3.1~7.6% and 1.3~4.1% with averages of 4.7% and 2.2%, respectively, and a total content of saturated fatty acid ranged 5.4~9.4% with an average of 6.9%. Oleic and linoleic acid contents, unsaturated fatty acid, ranged 18.1~75.7% and 18.1~74.1% with averages of 55.2% and 38.0%, respectively. Five accessions, IT031831, IT031669, IT031895, IT031938 and IT031694, showed higher oleic acid content than 70%. A total content of unsaturated fatty acid ranged 89.6~94.8% with an average of 93.0%.

• Korean Journal of Plant Resources
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• v.25 no.5
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• pp.624-632
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• 2012

As there have been lately many worldwide resource challenges such as potential exhaustion of fossil fuels, sudden rise of oil price and ever-rising grain pricing due to global food crisis, there have been more interests focused on recycling vegetable oils and fats into clean natural fuel and producing new resources based on waste cooking oil as a part of reusing waste resources. An Experiment was performed by using ratio of 50:50, 75:25 (w/w) mixture of based rapeseed oil, camellia oil, and olive oil. 50:50, 25:75 (w/w) mixture of based palm oil. The result was that the oleic acid ($C_{18:1}$) got the lowest percentage of 42.8%, when we combined the mixture of rapeseed oil and soybean oil. While the highest percentage of 72.1% was when the mixture of camellia oil and rapeseed oil were combined at 50:50 ratio. In 75:25 (w/w) case, mixture of rapeseed oil and soybean oil got the lowest. The highest ratio was the mixture of camellia oil and olive oil. Based on the component of palm oil, the total saturated fatty acid was decreased. It is expected that stabilizing oxidation through controlling of fatty acid after mixture and that liquidity at a low temperature. The acid value indicated that stabilizing oxidation got a range of highest to lowest. Camellia oil ranked as the highest, followed by olive oil, and the oil seeds as the lowest in rank. Controlling iodine value through mixture and improvement of stabilizing oxidation will provide a good quality. The quality of color has no significant change about mixture in ratio and maintenance. The reduction of the cost of refining process is expected by controling of mixture ratio at biodiesel production in the future.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.164-176
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• 2012

In the present study, rapeseed flour (RSF), which is a by-product from the production of edible oil and biodiesel extracted from rapeseed, was used to develop alternative adhesives for the production of plywood panels. To examine the effects of the enzyme on the adhesive properties and formaldehyde emission of the RSF-based adhesive resins, three enzymes, such as cellulase (CEL), pectinase (PEC) and protease (ALC), were used either separately or together. As a crosslinking agent, PF prepolymers, which were prepared with 1.5, 1.8 and 2.1 mole formaldehyde and 1 mol phenol (1.8-, 2.1- and 2.4-PF), were added into the RSF hydrolyzates. The adhesive resins formulated with CEL- or CEL-PEC-RSF hydrolyzates and 1.8-F/P PF prepolymers exhibited excellent adhesive strengths and formaldehyde emission. The tensile shear strength and formaldehyde emission of the plywood panels bonded with the formulate resins were satisfied with the minimum requirement of the KS standard for ordinary plywood panels (0.6 N/$mm^2$). In addition, formaldehyde emissions of the plywood panels approached to that of E0 specified in the KS standard (0.5 mg/${\ell}$), and even had much better than those of commercial UF glue mixes. Overall, the use of RSF-based adhesive resins for the production of plywood panels might provide durable adhesive properties and an environmentally friendly substitute for petroleum-based adhesive resins. However, further researches - the increase of solid content of RSF-based adhesives for reducing press time and the microscopic observation of plywood specimen for identifying the relationship between tensile shear strength and the penetration of adhesives into wood structure - are required to commercialize the RSF-based adhesives.