• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.316-322
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• 2010

The research attempted to develop a wood adhesive based on waste cooking oil, using ozonification technology for the chemical structure modification. The waste cooking oil (WCO) was reacted with $O_3$ for different times; 1 h, 2 h, and 3 h. The chemical structure modifications of the ozonized WCOs were examined by Fourier transform Infrared (FT-IR) spectrum. The FT-IR spectrum of WCO had an absorbance peak at 3,010 $cm^{-1}$ that was the characteristic peak of the unsaturated double bonds. As ozone treatment time increased, the peak of the double bond was disappeared and carboxyl peak appeared at 1,700 $cm^{-1}$. Especially, the double bond of 3 hrs-ozonized WCO was vanished almost. In results of the dry bonding strengths of the 3 hrs-ozonized WCO mixed with polymeric methylene diphenyl diisocyanate (pMDI) were the strengths of weight ratio of 3hrs-ozonized WCO : pMDI, 1 : 0.5, 8.08 kgf/$cm^2$, 1 : 0.75, 9.53 kgf/$cm^2$ 1 : 1, 44.16 kgf/$cm^2$, 1 : 2, 58.08 kgf/$cm^2$, 1 : 3, 61.41 kgf/$cm^2$, and 1 : 4, 46.95 kgf/$cm^2$. Therefore, it was found that the optimum equivalent ratio was formed at the ratio of 1 : 2 or 1 : 3. Under wetting the bonding strength of 1 : 3 ratio was appeared higher than that of 1 : 2 ratio, while the results obtained from hot-water and cyclic boiling shear test were similar.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.451-459
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• 2011

We investigated melting points and sensory characteristics by adding rice bran and roasted soybean to the finishing diet of Hanwoo steers. Thirty-six Hanwoo steers (average age, 20.92 mon-old; average weight, 599.89 kg) were assigned to either Control, Treatment 1 (rice bran) or Treatment 2 (roasted soybean) groups (12 steers/group), considering body weight and age. Supplementation levels of rice bran and roasted soybean were determined to meet total 5% crude fat in the concentrates, and the experimental animals were fed for 314 d until they reached 31.2 mon old. No significant differences were found in the moisture and crude fat content among groups. Melting points of lipid extracted from M. longissimus dorsi, subcutaneous fat, and perirenal fats were 25.83-26.17, 17.26-18.53 and $32.40-33.15^{\circ}C$, respectively, resulting in remarkable differences depending on fat depots. Contents of free amino acids in M. longissimus dorsi related to sweet taste were 39.48 mg/100 g for Treatment 1, which was significantly (p<0.05) higher than those for Control (32.24 mg/100 g), whereas those related to bitter taste were 25.93 mg/100 g for Treatment 2, which was the lowest (p<0.05) among the groups. Fatty acid composition, such as $C_{14:0}$, $C_{16:0}$, $C_{16:1}$, $C_{18:0}$, and $C_{18:1}$, in M. longissimus dorsi was not different among the groups. Results of a panel test on M. longissimus dorsi showed that Treatment 1 scored the highest (p<0.05) in juiciness, and both Treatments 1 and 2 scored higher (p< 0.05) in overall palatability than the Control group. $C_{18:1}$ showed a positive (+) relationship with tenderness (r = 0.650; p<0.05), and $C_{18:0}$ with flavor (0.698; p<0.05). The results suggest that rice bran and roasted soybean are beneficial for improving M. longissimus dorsi sensory characteristics, whereas no significant differences were found in the physico-chemical characteristics among the groups.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.261-269
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• 2015

The purpose of this research is to identify the significance of climate factors related to the significance of change of dry matter yield (DMY) of whole crop maize (WCM) by year through the exploratory data analysis. The data (124 varieties; n=993 in 7 provinces) was prepared after deletion and modification of the insufficient and repetitive data from the results (124 varieties; n=1027 in 7 provinces) of import adaptation experiment done by National Agricultural Cooperation Federation. WCM was classified into early-maturity (25 varieties, n=200), mid-maturity (40 varieties, n=409), late-maturity (27 varieties, n=234) and others (32 varieties, n=150) based on relative maturity and days to silking. For determining climate factors, 6 weather variables were generated using weather data. For detecting DMY and climate factors, SPSS21.0 was used for operating descriptive statistics and Shapiro-Wilk test. Mean DMY by year was classified into upper and lower groups, and a statistically significant difference in DMY was found between two groups (p<0.05). To find the reasons of significant difference between two groups, after statistics analysis of the climate variables, it was found that Seeding-Harvesting Accumulated Growing Degree Days (SHAGDD), Seeding-Harvesting Precipitation (SHP) and Seeding-Harvesting Hour of sunshine (SHH) were significantly different between two groups (p<0.05), whereas Seeding-Harvesting number of Days with Precipitation (SHDP) had no significant effects on DMY (p>0.05). These results indicate that the SHAGDD, SHP and SHH are related to DMY of WCM, but the comparison of R2 among three variables (SHAGDD, SHP and SHH) couldn't be obtained which is needed to be done by regression analysis as well as the prediction model of DMY in the future study.