• Conservation Science in Museum
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• v.6
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• pp.55-66
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• 2005

Three types of epoxy resins (Epo-Tek 301, Araldite 103, and Araldite 106) and three types of pigments (bunche, pastel, and conté), which are materials for porcelain restoration, were selected as examination materials. The tone change, porosity, and sedimental resulting from the mixtures of varying ratios of these three materials were observed. Samples were also made from the mixture of Epo-teck 301, four kinds of white pigments, and six types of fillers and subjected to ultraviolet ray penetration for 200 hours to observe the oxidation of the epoxy resins. The result showed that the chemical composition of pastel drastically changed when mixed with Epo-tek 301. Although bunche and conté displayed clear colors, those of conté were less clear when it was mixed with other substances. Adding a small amount of Epo-tek 301 tended to be driven into the corner, whereas mixing a large amount caused saturation and boiling. On the other hand, AW 106 did not display clear colors owing to its high viscosity; when mixed in large amounts, however, the clarity of colors improved. For AY 103, a similar standard of color clarity was maintained regardless of the mixture ratio. The following was ranked according to the level of porosity: [Pastel>bunche≒conté]. In terms of sedimentary, however, [bunche>conté>Pastel], [Epo-tek 301> AY 103> AW 106]. The result of measuring the degree of yellowing revealed that titanium, pastel, silicon dioxide, and kaolin tended to turn yellow, whereas bunche, conté, diatomaceous earth, and calcium hydroxide tended to resist yellowing.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.253-259
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• 2004

The effect of dietary clay mineral on meat quality in M. longissimus of Hanwoo (Korean cattle) bull beef during refrigerated storage (4$^{\circ}C$) was investigated. Experimental groups were divided into control (basal diet) and CT-1.25% (basal diet + 1.25% clay mineral) groups. There was no significant differences in proximate and fatty acid compositions between control and CT-1.25% groups. The pH of control group was significantly (p<0.05) changed during storage, but CT-1.25% group was little affected by storage time. CIE a＊ (redness), chroma (C＊) values and R630-R580 were significantly (p<0.05) decreased during storage for both groups. In particular, those values decreased more rapidly in the control group. The rate of metmyoglobin accumulation during storage increased more rapidly in the control group. Therefore, discoloration in the control group was more accelerated compared to the CT-1.25% group. TBARS (thiobarbituric acid reactive substances) which represents lipid rancidity were significantly (p<0.05) lower in CT-l.25% group than in the control. Water-holding capacity (WHC) was significantly (p<0.05) increased during storage for both groups, and CT-1.25% group had significantly (p<0.05) higher WHC than control group. Consequently, feeding of clay mineral (1.25%) was effective in increasing meat color stability and WHC, and retarding lipid oxidation than did control group.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.29-33
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• 1999

To investigate the effects of Angelica gigas Nakai diet on lipid metabolism, alcohol metabolism and liver function of rats administered with chronic ethanol, Sprague-Dawley male rats were fed either AIN-76 diet (control), control diet with ethanol, control plus Angelica gigas Nakai diet, or control plus Angelica gigas Nakai diet with ethanol for 30 days. On the 21st day, all of the rats were given an oral dose of ethanol and blood-ethanol concentration was monitored for the next 5 hours. The results obtained were: 1) Upon ethanol administration, the blood ethanol concentration was decreased from 2 hr significantly in the group of control plus Angelica gigas Nakai diet compared with control diet group; 2) The blood ethanol oxidation rate was increased in the group of control plus Angelica gigas Nakai diet with ethanol compared with control diet group or control plus Angelica gigas Nakai diet group. After 30 days, rats were sacrificed and then lipid and enzyme determinations in blood and liver were carried out. The results obtained were: 1) LDL-cholesterol in the blood of control plus Angelica gigas Nakai diet group was decreased significantly compared with control diet group; 2) Angelica gigas Nakai diet decreased liver triglyceride and total lipid and blood ${\gamma}-GTP$ level increased due to the chronic ethanol administration. These data suggest that Angelica gigas Nakai can have a recovery function on the symptoms of alcohol related diseases.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.478-482
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• 1995

The changes of the lipid composition and of the contents of carotenoid and tocopherol in wheat germ were studied during the storage at $30^{\circ}C$. The contents of triglyceride and free fatty acid were changed from 66% and 7% to 49% and 24% respectively after 30 days. The predominant free fatty acids were lauric acid (29%), palmitic acid (21%) and linoleic acid (20%), however, linoleic acid increased to 30%, lauric acid reduced to 21% after storage of 30 days. The carotenoids in the wheat germ were ${\beta}-carotene,\;{\alpha}-carotene$, lutein and taraxanthin, and the contents of these were 306, 59, 383 and 356 ng/g wheat germ, respectively. Their contents, however, were reduced to 36, 4, 203 and 149 ng respectively after 20 storage days. Especially, degradation rate of ${\beta}-carotene$ was 22.5 ng/day. The tocopherol isomers in wheat germ were ${\alpha}-,\;{\beta}-\;and\;{\gamma}-tocopherol$, and they reduced from $55,\;48\;and\;38\;{\mu}g/g$ wheat germ to 35, 32 and $32\;{\mu}g$ respectively after 20 storage days. The ${\alpha}-tocopherol$ was degraded by $1.26\;{\mu}g/day$ at this storage condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.734-737
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• 2005

This study was conducted to determine the effect of effective microorganism (EM) treatment in feeding system of swine on carcass characteristics. EM pork, which reared with EM additives and EM activated liquids, and conventional pork (non-EM pork) were stored at $4^{\circ}C$. Chemical composition and storage stability of EM pork were compared with conventional pork. Cholesterol content at EM pork was 71 mg/100 g, which is lower than that of conventional pork (83 mg/100 g) when the meats were stored at $4^{\circ}C$ refrigerator. And EM pork (0.165 MDA mg/kg) showed higher antioxidant effect than control pork (0.184 MDA mg/kg). And also protein denaturalization at EM pork showed lower rate $(3.19\;mg\%)$ than that of conventional pork $(4.9\;mg\%)$ when the meats were stored at $4^{\circ}C$ refrigerator, showing that inhibitory effect of protein denaturalization was increased up to $35\%$ over the conventional pork. These results show that the EM pork had superior traits in terms of cholesterol level, lipid oxidation and protein denaturalization to the conventional pork.

• Food Science of Animal Resources
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• v.22 no.2
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• pp.108-114
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• 2002

The effects of dietary vitamin E and selenium(Se) supplementation on meat color stability in M. Longissimus of Hanwoo(Korean native cattle) bull beef during retail display(5$^{\circ}C$, 1,200 lux) were investigated. Experimental groups were divided into control(Vit E 27 IU/head/day, Se 0.09 mg/head/day), Vit E (2,500 IU/head/day), Se(20 mg/head/day), Vit E+Se(Vit E 2,500 IU/head/day, Se 20 mg/head/day) groups. CIE a*(redness), chroma(C*) values, oxymyoglobin(%) and R630-R580 were significantly (p<0.05) decreased among the 4 treatment groups during retail display, in particular, those values decreased more rapidly in the control group. The metmyoglobin (%) of 0 day(before storage) was not significantly (p<0.05) different among the 4 treatment groups. However, the rate of metmyoglobin accumulation during storage increased more rapidly in the control group. Therefore, discoloration in the control group was more accelerated compared to the other groups. TBARS(thiobarbituric acid reactive substances) which represent lipid rancidity was significantly(p<0.05) lower in Se and Vit E+Se groups than in the control and Vit E groups. Reducing ability of 0 day(before storage) was significantly lower in the control group than in the other groups, and it decreased more rapidly in the control group after 3 days of storage. Consequently, Se-supplemented groups(Se and Vit E+Se groups) were more resistant to lipid oxidation than were the control and Vit E groups. The stability of meat color and myoglobin forms(%) were significantly (p<0.05) higher in Vit E, Se and Vit E+Se groups than in the control group, but there were no difference among Vit E, Se and Vit E+Se groups.

• Korean Chemical Engineering Research
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• v.55 no.2
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• pp.270-274
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• 2017

Formic acid has been known as one of key sources of hydrogen. Among various monometallic catalysts, hydrogen can be efficiently produced on Pd catalyst. However, the catalytic activity of Pd is gradually reduced by the blocking of active sites by CO, which is formed from the unwanted indirect oxidation of formic acid. One of promising solutions to overcome such issue is the design of alloy catalyst by adding other metal into Pd since alloying effect (such as ligand and strain effect) can increase the chance to mitigate CO poisoning issue. In this study, we have investigated formic acid deposition on the bimetallic $Pd/Pd_3Fe$ core-shell nanocatalyst using DFT (density functional theory) calculation. In comparison to Pd catalyst, the activation energy of formic acid dehydrogenation is greatly reduced on $Pd/Pd_3Fe$ catalyst. In order to understand the importance of alloying effects in catalysis, we decoupled the strain effect from ligand effect. We found that both strain effect and ligand effect reduced the binding energy of HCOO by 0.03 eV and 0.29 eV, respectively, compared to the pure Pd case. Our DFT analysis of electronic structure suggested that such decrease of HCOO binding energy is related to the dramatic reduction of density of state near the fermi level.

• KSBB Journal
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• v.9 no.3
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• pp.239-245
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• 1994

The effects of reaction temperature and the level of hydration(water activity) were studied for gas phase reactions of alcohol oxidase and alcohol dehydrogenase immobilized on DEAE-cellulose and controlled pore glass(CPG). Optimum reaction temperature zone of gas phase reaction was similar to that of aqueous phase reaction. The activity of alcohol oxidase increased dramatically and the stability decreased when the water activity was increased from 0.3 to 0.8. The apparent activation energies of the gas phase reaction decreased approaching the values obtained in the aqueous phase reaction as the water activity increased. In the both cases of alcohol oxidase and alcohol dehydrogenase, the rate constants of the gas phase reaction were lower than those of aqueous phase reaction by two orders of magnitude and these results could be correlated to the vapor-liquid equilibrium data of the substrate, ethanol.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.387-393
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• 2011

This study was conducted to find the effects of microclimates such as air and soil temperature, photosynthetic photon flux density (PPFD) on the berry development and physiological property between cultivation conditions (open field and rain shelter house) in 'Northland' blueberries (Vaccinium corymbosum). The rate of berry growth and development was stimulated in plants grown in rain shelter house, thus, berry reached to the ripe stage about one week earlier than those in open field. Berry weight and size at ripe stage seemed not affected by microclimates. However, total soluble solids content was higher in berries from open field whereas the titratable acidity was significantly higher in berries grown in rain shelter house. Berry firmness at ripe stage was little affected by growing condition. Total anthocyanin content of ripe berries was higher in berries harvested from rain shelter house. Total phenolics content and anti-oxidation activity of berries were higher in open field than those of rain shelter house during berry development but no differences were found at ripe berries.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.5
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• pp.383-393
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• 2007

The aim of the present study is to investigate the effect of anodized surface of osseointegration implants by using of resonance frequency analysis (RFA) and histomorphometric analysis. A total of 96 screw-shaped implants were devided into 4 groups. Seventy-two implants were prepared by electrochemical oxidation with 3 different ways; Group 1 (n=24) were prepared at galvanostatic mode in 0.25M sulfuric acid and phosphoric acid, Group 2 (n=24) were prepared at galvanostatic mode in calcium glycerophosphate and calcium acetate, and Group 3 (n=24) were prepared at galvanostatic mode in 0.25M sulfuric acid and phosphoric acid followed by Calcium metaphosphate(CMP) coating. Control group (n=24) were the RBM surfaced implants. The implants were placed in the mandibles of 12 mini pigs. Bone tissue responses were evaluated by resonance frequency analysis(RFA) and histomorphometric analysis that were undertaken at 2, 4 and 6weeks after implant placement. The following result were obtained. 1. Twenty-two of 96 implants (4 in control group, 5 in group 1, 7 in group 2, and 6 in group 3) were failed due to faliure of osseoitegration. The failure rate of osseointegration was 22.9%. 2. The mean values of RFA in control, group 2 and groups 3 showed the similar values, but there was no significant difference among groups. 3. Histomorphometric evaluation demonstrated significantly higher bone-to-implant contact ratio in group 2 at 3 and 4 weeks after implant placement than other groups (p<0.05), but there was no significant difference among groups at 6weeks after implant placement.