• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.121-127
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• 2010

This study is to optimize the enzyme(lipase) activity for biodiesel production. The ion-exchanged non-woven fabrics(EtA, DEA-EtA non-woven fabric) containing ethanolamine, diethylamine groups are used by radiation induced grafted polymerization onto a non-woven fabric for more effective immobilization of lipase. Since the porous hollow fiber membranes are showed the low throughputibehe non-woven fabric membranes are used for biodiesel production. The physical charateristics of enzyme immobilized and the enzyme activity to EtA and DEA-EtA non-woven fabrics are studied. The EtA non-woven fabrics are quite similar to DEA-EtA non-woven fabric for the amount of enzyme immobilized(EtA non-woven fabric:15.69 mg/g, DEA-EtA non-woven fabric:14.45 mg/g) but DEA-EtA non-woven fabrics have shown the lower permeabiliquite the organic solvent than the EtA non-woven fabrics(EtA non-woven fabric:$3.50mol/h{\cdot}kg$, DEA-EtA non-woven fabric:$0.38mol/h{\cdot}kg$). Optimum characteristics of ehe non-woven fabric membranes and the limilaractivity are also investigated for the effective biodiesel production.

• Elastomers and Composites
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• v.48 no.4
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• pp.288-293
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• 2013

Crosslink characteristics of maleic anhydride-grafted EPDM (MAH-g-EPDM)/zinc oxide composite were investigated by weight losses after dichloroacetic acid (DCA)/toluene cosolvent extraction at different temperatures and by measurement of crosslink densities. The chemical changes were analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The weight losses by extraction at high temperature ($90^{\circ}C$) were remarkably greater than those at room temperature and those by DCA/toluene cosolvent extraction were greater than those by toluene one by more than 5 times. The crosslink densities were measured after the solvent extraction, and the second crosslink densities were higher than the first ones. The first crosslink density was lower when the extraction temperature was high, and it was much lower for the toluene extraction than for the DCA/toluene cosolvent extraction. The second crosslink density of the sample extracted with DCA/toluene cosolvent was greater than that extracted with toluene. The extracted components were depending on the extraction solvents and temperatures, for example; only strong crosslinked networks were remained when extracting with DCA/toluene cosolvent at high temperature, while only uncrosslinked polymer chains were extracted when extracting with toluene at room temperature. Therefore, crosslink characteristics of the MAH-g-EPDM/zinc oxide composite can be analyzed by comparison of the extracted components according to the extraction solvents and temperatures and by measurement of successive crosslink densities.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.1
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• pp.33-39
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• 2010

Printing technologies have been indicated as alternative methods for patterning conductive, semi-conductive or insulative materials on account of their low-cost, large-area patternability and pattern flexibility. For application of the printing technologies in manufacture of semiconductor or display modules, ink or paste composed of nanoparticles, solvent and additives are basically needed. Here, we report recent advances in eco-friendly nano-ink technology for semiconductor and display technology. Then, we will introduce an eco-friendly ink formation technology developed in our group with an example of manufacturing $SiO_2$ nanopowders and inks. We tried to manufacture ultrafine $SiO_2$ nanoparticles by applying a low-temperature synthetic method, and then attempted to fabricate the printed $SiO_2$ film onto the glass substrate to see whether the $SiO_2$ nanoparticles are feasible for the printing or not. Finally, the electrical characteristics of the films were measured to investigate the effect of the manufacturing parameters.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.99-105
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• 2002

This study investigated characteristics of ICR18650 batteries with different electrolyte compositions in the range of $80^{\circ}C\~-30^{\circ}C$. ICR18650 cells using $1M\;LiPF_6,\;EC:\;DEC:\;DMC(3:5:5)\;and\; 1M\;LiPF_6,\;EC:\;DEC:\;DMC:\;EMC(3:5:4:1)$ electrolyte systems, which DMC and EMC solvent were added in $1M\;LiPF_6,\;EC:\;DEC$ electrolytes have high specific energy in the wide range of temperature. The specific energy of ICR18650 batteries using $1M\;LiPF_6,\;EC:\;DEC:\;DMC(3:5:5)\;and\; 1M\;LiPF_6,\;EC:\;DEC;\:\;DMC:\;EMC(3:5:4:1)$ electrolyte at $-30^{\circ}C\;was\;64\%\;and\;59\%$ of room temperature$(25^{\circ}C)$, respectively.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.98-106
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• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.242-247
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• 2013

Currently, methods for controlling weeds in organically produced crops have not been as effective as conventional methods. This research was carried out to determine the herbicidal effects of leaf, stem, fruit, root extracts of Trichosanthes kirilowii. The extraction methods used were water, boiling water and ethanol. The characteristics of potential herbicidal components among extraction methods were investigated by using the following solvent fractions: hexane, chloroform, ethyl acetate, butanol, and water. Generally, water extracts provided the best on inhibition of germination rate, plant height, and root length in cucumber and barley. Specifically, extractions made from fruit parts of T. kirilowii provided the greatest inhibition effect on plant growth in cucumber and barely. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fractions, but there were no significant differences among the other fractions. Digitaria siliaris and Solanum nigrum were controlled 80-100% by 5% extractions of water fraction. However, there were no herbicidal effects from foliar treatment in cucumber, barley, black nightshade, and henry crabgrass by 5% extractions of the water fraction. These results show that extractions of T. kirilowii can be used for controlling some weeds in organically produced crops.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.65-77
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• 2020

In order to industrialize of Dendranthema indicum (L.) DesMoul., which is a lot of commercially available and is synonymous with chrysanthemum tea, in the autumn of 2018, Dendranthema indicum (L.) DesMoul. seeds were collected from its own native region, and the seeds were germinated after refrigerated storage. Young seedlings were subjected to experiments in February, March, and April in the open field to examine the effects on the harvesting of leaves by distance and the growth of leaves and stems. The results of analyzing the components by collecting the leaves+stem after collecting the flower of Dendranthema indicum (L.) DesMoul. are as follows. 1. When D. indicum (L.) DesMoul. seedlings were planted according to the transplanting date, the number of flowers was 17.1 in the transplanting date in April. The diameter of the flower was 2.9cm, 16ea, 6.5~6.6g in the fresh weight, and the dry weight of the case was 1.1~1.2g. The leaves were 46~47ea in March and April in the planted area, 5.2~5.3cm in leaf length and 3.5~3.6cm in leaf width. 2. When planted D. indicum (L.) DesMoul. seedlings according to transplanting distance, the number of flowers was 16.2 when planted at 20×20cm intervals and, 16.8~17.1 at 30×30~50×50cm intervals. The diameter of the flower was 2.7~2.8cm, the number of petals was 8, the length of the petal was 0.8 cm, and fresh weight was 6.5~6.6g per flower. Leaves had the largest number of 47 of 30×30cm and 40×40cm, and leaf length appeared at the longest 6.2cm in the 50×50cm treatment area, but 5.2cm in the other treatment areas. 3. The extraction yield of D. indicum (L.) DesMoul. leaves+stems was 7.93%, and the extraction solvent colors were light green at 50, 60% and green at 70, 80, 90, 100%. The extraction yield of D. indicum (L.) DesMoul. flowers was 7.58%, the color of the extraction solvent was light yellow at 50, 60 and 70%, yellow at 80 and 90%, and dark yellow at 100%. 4. We confirmed 11 kinds of ingredients such as in D. indicum (L.) DesMoul. flowers are gallic acid, 4-hydroxy benzoic acid, methyl gallate, 4-hydroxy-3-methoxy benzoic, caffeic acid, salicylic acid, p-coumaric acid, sinapic acid, naringin, 4-melthoxyben, flavone. The content was 29.200-36.900ppm. 5. The components contained in the D. indicum (L.) DesMoul. leaf+stem, salicylic acid appeared at 6,129.526ppm, and the next 4-methoxyben was 1,966.714ppm. It was methyl gallate 8.197ppm, 4-hydroxy-3-methoxy benzoic 6.994ppm, caffeic acid 5.566ppm, flavone 4.522ppm, p-coumaric acid 3.787ppm, gallic acid 1.893ppm that appeared in the content below 10ppm.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.626-632
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• 2013

This study was performed to determine the antioxidant activity of the oven-dried paprika powder as affected by the color differences of paprika and to evaluate physicochemical characteristics and antioxidant activity of pork patties with various levels of paprika powders. The total phenolic contents of the paprika were not affected by color and solvent (p>0.05). The methanol extracted paprika powder showed higher DPPH radical scavenging activity than water extracted counterpart, and no differences were observed at concentration of 0.5% as compared to the reference (ascorbic acid) (p>0.05). In all treatments, the iron chelating ability increased with increasing concentrations. At a concentration of 1.0%, methanol extracts of orange paprika (MOP) and water extracts of red paprika (WRP) were not different from the reference, (ethylendiaminetetraacetic acid, EDTA). The paprika color and extraction solvent didn't affect reducing power of paprika powder at each concentration (p>0.05). Pork patties with red paprika powder were higher redness values than those with orange ones, regardless of addition level. The addition of red paprika increased the yellowness, and patties with 1.0% orange paprika powder showed the highest value. TBARS values were decreased with increasing paprika powder, especially, patties with 1.0% paprika powder were lower TBARS than those with 0.5% paprika powder, resulting in similar to those with ascorbic acid (p>0.05). Although the microbial counts increased with storage time, paprika powders did not inhibit microorganisms during storage. In conclusion, paprika powders could be used as a natural antioxidant in meat products, regardless of paprika color.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.116-126
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• 2013

Glycol ethers are a group of solvents based on alkyl ethers of ethylene glycol commonly used in paints. These solvents typically have a higher boiling point, together with the favorable solvent properties of lower-molecular weight ethers and alcohols. The word "Glycol ethers" was registered as a United States trademark by Union Carbide Corp. Typically, glycol ethers are found in pharmaceuticals, sunscreens, cosmetics, inks, dyes and water based paints. On the other hand, glycol ethers are used in degreasers, cleaners, aerosol paints and adhesives. Most glycol ethers are relatively water soluble, biodegradable and only a few are considered toxic. Therefore, they are unlikely to pose an adverse risk to the environment. Recent study suggests that occupational exposure to glycol ethers is related to low motile sperm count in men, but the finding has been disputed by others. In this study, skin permeation of 3 types glycol ethers were studied in vitro using matrix such as solvent and detergent. The absorption of glycol ethers[methyl glycol ethers(MC), ethyl glycol ethers(EC) and butyl glycol ethers(BC)] has been measured in vitro through rat skin. Epidermal membranes were set up in Franz diffusion cells and their permeability to PBS measured to establish the integrity of the skin before the glycol ethers were applied to the epidermal surface. Absorption rates for each glycol ethers were determined and permeability assessment made to quantify any irreversible alterations in barrier function due to contact with the esters. Types of glycol ethers in vitro experimental results on MC> EC> BC quickly appeared in the following order: skin permeation was beneficial to the skin permeation small molecular weight, the difference in chemical structure, such as hydrophilic, because with the partition coefficient and solubility mechanisms and passive diffusion to increase the speed at which transmission is considered.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.609-614
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• 2013

This study investigated the spontaneous combustion behavior of solvent-treated low rank coals. Indonesian lignite (a KBB and SM coal) and sub-bituminous (a Roto coal) were mixed with non-polar 1-methyl naphthalene (1MN) either by mechanical agitation or ultrasonication. The property change associated with 1MN treatment was then analyzed using proximate analysis, calorific value analysis, Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy and moisture re-adsorption test. Susceptibility to spontaneous combustion was evaluated using crossingpoint temperature (CPT) measurement along with gas analysis by GC. A FT-IR profile showed that oxygen functional groups and C-H bonding became weaker when treated by 1 MN. XPS results also indicated a decrease of the oxygen groups (C-O-, C=O and COO-). Increased hydrophobicity was found in the 1MN treated coals during moisture readsorption test. A CPT of the treated coals was ${\sim}20^{\circ}C$ higher than that of the corresponding raw coals and the ultrasonication was more effective way to enhance the stability against spontaneous combustion than the agitation. In the gas analysis less CO and $CO_2$ were emitted from 1MN treated coals, also indicating inhibition of pyrophoric behavior. The surface functional groups participating in the oxidation reaction seemed to be removed by the ultrasonication more effectively than by the simple mechanical agitation.