• Journal of Korea Foundry Society
• /
• v.7 no.1
• /
• pp.45-52
• /
• 1987

The effects of melting and casting conditions on cast structures of Cu-Sn-Pb alloys were studied. Specimens were prepared at different pouring temperatures of $1100^{\circ}C$ to $1260^{\circ}C$ with use of various kind of molds, green sand mold, $CO_2$ sand mold, shell mold, furan sand mold and metallic mold. (1) The transition of equiaxed to columnar structure greatly influenced by adding elements and mold binders. (2) The change of equiaxed structure according to pouring temperatures were expressed by separation theory. Lower pouring temperature and rapid cooling rate increase hardness and it's further increase was shown in the region of columnar structure. (3) Proper controls of pouring temperature, cooling rate and mold binder were important factors to improve wear properties of Cu-Sn-Pb alloys castings.

• Food Science of Animal Resources
• /
• v.26 no.4
• /
• pp.441-446
• /
• 2006

The objective of this study was to investigate volatile compounds extracted from fresh pork belly during storage time at 4 or $20^{\circ}C$. Approximately thirty-one volatile compounds includingaromatics (6), aldehydes (6), acids (5), alcohols (4), ketones (4), alkanes (4), alkenes (1) and amines (1) in fresh pork belly were identified. Among them, volatile compounds such as 1-butanol, propane, 2-butanol, 3-hydroxy-2-butanone, acetic acid, 3-methyl-1-butanol, 1-pentanol, phenol, 2-pentyl-furan, indole and 2-dodecanone correlated with storage temperature and storage time. Aldehydes including hexanal and hexadecanal at 4t were the predominant volatile compounds, whereas at $20^{\circ}C$ storage, aromatics including phenol and indole, and alcohols including 2-butanol and 1-butanol were the predominant volatile compounds. Contents of 1-butanol, 2-butanol, 3-hydroxy-2-butanone, acetic acid, phenol and indole increased markedly with increased storage time, and 1-butanol, 2-butanol, 3-hydroxy-2-butanone, acetic acid, indole and 2-dodecanone were only detected at $20^{\circ}C$ storage.

• Korean Journal of Food Science and Technology
• /
• v.20 no.2
• /
• pp.157-163
• /
• 1988

The volatile compounds produced from the browning reaction of 0.5M DL-alanine and 0.5M D-glucose mixture using propylene glycol as a reaction medium were analysed by gas chromatography and gas chromatography-mass spectrometry and effects of temperature($100^{\circ}C,\;120^{\circ}C,\;140^{\circ}C$) and time(20min, 2hours) on the formation of volatile compounds were investigated. Browning reaction were rapidly increased as the reaction temperature and time increased. From methylene chloride extracts, twenty six compounds, including 7 alkyl pyrazines. 4 pyrroles, 3 furans, 1 furanone and 11 miscellaneous compounds were identified. The relative amounts of pyrazines, pyrroles and furans were markedly increased as reaction temperature and time increased. The results showed that caramel-like and burnt sugar-like aroma produced by alanine -glucose reaction must be mainly comprised of nitrogeneous heterocyclic such as pyrazines, pyrroles and oxygen heterocyclic compounds such as 2-hydroxy-3-methyl-2-cyclopenten-1-one and 2,5-dimethyl-4-hydroxy-3(2H)-furanone.

• Korean Journal of Weed Science
• /
• v.30 no.4
• /
• pp.421-428
• /
• 2010

A foliage contact herbicidal substance was separated from ethyl ether fraction in n-hexane extract of Saussurea lappa roots and identified as dehydrocostus lactone [(3aS,6aR,9aR,9bS)-3,6,9-trimethylidene-3a,4,5,6a,7,8,9a,9b-octahydroazuleno[5,4-d]furan-2-one](DHCL). When DHCL at 4,000 ppm was foliage-applied to two grasses and two broadleaf plants, greater than 85% necrotic injury was obtained from large crabgrass, maize and soybean, whereas only about 40% necrotic injury appeared in black nightshade, indicating that DHCL has no gross morphological selectivity, but shows difference in contact response among the plant species tested. Conductivity in incubation medium of the leaf disks treated with DHCL increased as the incubation time continued. Relatively low contact injury in black nightshade as compared with the other three plant species tested was attributed to decrease in absorption of DHCL due to relatively high amount of cuticle. DHCL did not require light in the herbicidal action and there were no inhibitory effects on seed germination and cell elongation. Acetyl-CoA carboxylase activity was inhibited by 30% and 58% at $100\;{\mu}M$ and $1000\;{\mu}M$ DHCL, respectively. These results suggested that the herbicidal action of DHCL was related with inhibition of fatty acid synthesis which in turn caused to weaken cell membrane integrity.

• Korean Journal of Food Science and Technology
• /
• v.32 no.6
• /
• pp.1258-1265
• /
• 2000

In oder to acquire microbial agents that can be utilized for control of aflatoxin produced by Aspergillus. flavus and Asp. parasiticus, antifungal bacteria were isolated. Antifungal bacteria was identified as Bacillus spp. based on morphology and physico-biochemical characteristics. Amount of aflatoxin $B_1$ from Doenjang(soybean paste) prepared with Asp. flavus, Asp. parasiticus, antifungal bacteria(Bacillus sp.), or mixture of Asp. flavus and Asp. parasiticus was 27.2 ppb, 30.3 ppb, 3.4 ppb, and 3.7 ppb, respectively. Aflatoxin $B_1$ was not detected from Doenjang(control) and Doenjang prepared with antifungal bacteria. Content and compositions of free sugars, fatty acid, organic acid and free amino acid in Doenjang prepared with Asp. flavus and Asp. parasiticus, antifungal bacteria and mixture of Asp. flavus and Asp. parasiticus were not significantly different. For volatile flavor compounds of Doenjang prepared with antifungal bacteria, 2-pentyl furan and butanoic acid were disappeared or reduced, while octadecene compounds were produced. However, those of Doenjang prepared with Asp. flavus or Asp. parasiticus and Doenjang(control) were not significantly different. These results suggested that the antifungal bacteria(Bacillus sp.) inhibited production of aflatoxin and that antifungal bacteria did not effect the quality of Doenjang.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.2
• /
• pp.142-149
• /
• 1999

Moisture absorption rate of rice according to the soaking time was higher at $25^{\circ}C$ than 4$^{\circ}C$ and the op-timum soaking time was 1hr at $25^{\circ}C$. When the ratios of added water for rice cooking were 1.3 in an elec-tric cooker and pressure cooker and 1.7 in an Dookbaeki sensory an mechanically evaluation of cooked rice were highly evaluated. The total number of peak on gas chromatography profile were 89 in an press-ure cooker 56 in an electric cooker and 83 in an Dookbaeki and major volatile compounds of cooked rice were aliphatic hydrocarbons cyclic hydrocarbons aromatic hydrocarbons aldehydes alcohols ketones and thiourea. Furan that is in sweety was not detected in volatile components of cooked rice of electric cooker.

• Journal of Korea Foundry Society
• /
• v.9 no.5
• /
• pp.403-412
• /
• 1989

This study has been carried out to investigate into the properties of molding sands containing various core sands, $CO_2$, Shell, Furan, Pep Set and Cold Box, in the system sands using domestic active bentonite. The properties of system sands with 5% bentonite and 3% moistures containing baked core sands and no-baked core sands were varied by the ratio of core sands. The system sand containing no-baked core sands had been the poor bonding force and rough grain surface than those of the baked core sands. The L. O. I of system sand containing 30% organic binders core sands were more than inorganic binders core sands. It has been found that the no-baked core sands were necessary have to reclaim for using molding sand.

• Journal of the Korean Chemical Society
• /
• v.13 no.1
• /
• pp.56-61
• /
• 1969

By the chemical procedure and infra-red spectroscopy, the characteristics of humic acid were studied. The results were as follows: 1. Molecular weight. 5,200. 2. Molecular formula. $C_{240}H_{250}O_{120}N_{1O}$. 3. Rational formula. 4. Confirmation of the accurate structure of humic acid is beyond us nowadays. The structure is speculated that it may be a kind of condensed polymer of many benzene kerns in which above mentioned various functional groups are attached. Also some part of the large quantities of oxygen would be furan type carbonyl and aliphatic ethereal forms.

• Preventive Nutrition and Food Science
• /
• v.14 no.1
• /
• pp.76-85
• /
• 2009

This study determined the effect of refrigerated and thermal storage on the volatile profile of commercial aseptic soymilk. Volatile components in commercial aseptic soymilk stored either under refrigerated ($4^{\circ}C$) or thermal ($55^{\circ}C$) conditions for 30 days were periodically analyzed by combined solvent-assisted flavor evaporation-gas chromatography-mass spectrometry (SAFE-GC-MS). The concentrations of most of the volatile components, including aldehydes, ketones, alcohols, acids, nitrogen- and sulfur-containing compounds, alkylfurans, furan derivatives and phenolic compounds, were affected to a greater extent by thermal storage compared with refrigerated storage. Profound increases in some volatile compounds with low odor detection thresholds, such as hexanal, octanal, (E)-2-octenal, (E,E)-2,4-decadienal, 1-octen-3-ol, 3-ethyl-2,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, 2-pentylfuran, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, dimethyl trisulfide, guaiacol, 4-vinylguaiacol and 4-vinylphenol, were observed in thermal stored soymilk. The volatile profile changes caused by thermal storage may influence the aroma quality of thermal-stored aseptic soymilk.

• Biomedical Science Letters
• /
• v.20 no.2
• /
• pp.62-69
• /
• 2014

Previous our study demonstrated that ailanthoidol (3-deformylated 2-arylbenzo[b]furan), a neolignan from Zanthoxylum ailanthoides or Salvia miltiorrhiza Bunge, is a novel anti-inflammatory agent. In this investigation, we examined the anti-adipogenic effect of ailanthoidol. Our data showed that ailanthoidol suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells. Treatment of the 3T3-L1 adipocytes with ailanthoidol resulted in an attenuation of the releases of leptin and interleukin-6. The expression of peroxisome proliferator-activated receptor $(PPAR){\gamma}$ and CCAAT/enhancer-binding protein $(C/EBP){\alpha}$, the central transcriptional regulators of adipogenesis, was decreased by treatment with ailanthoidol. Additionally, ailanthoidol treatment increased the phosphorylation levels of 5' adenosine monophosphate-activated protein kinase. These results suggest that ailanthoidol effectively suppresses adipogenesis and that it exerts its role mainly through the significant down-regulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$ expression. Our findings provide important insights into the mechanisms underlying the anti-adipogenic activity of ailanthoidol.