• Clean Technology
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• v.9 no.2
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• pp.57-61
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• 2003

A novel nitric acid-free desmut solution has been developed to remove smut, which is produced from a NaOH etching, on the surface of aluminum alloy metal in metal surface treatment processes. Comparing with the performance of 5% $HNO_3$ desmut solution, the mixed acid solution containing 2% $H_2O_2$, 0.5% HF, and 10% $H_2SO_4$ shows the same effect of smut removal for aluminum alloy samples of A16061 and A15052. To examine the surface alterations of the aluminum samples, in addition, the surface analysis is carried out with scanning electron microscopy (SEM) and electron probe microanalysis (EPMA).

• Journal of Life Science
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• v.11 no.6
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• pp.517-522
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• 2001

To Confirm the repression of off-odor and improvement of food quality in small black bean chungkugjang (SBC), some taste compounds of SBC added with kiwi and radish homogenate and fermented fro 3 days at 42$^{\circ}C$ were investigated. Contents of free amino acids in SBC were lower than that of soybean chungkugjang (SC) and were increased by adding kiwi and radish homogenate to black bean, indicating that two materials were effective to the enzymatic digestibility of soy protein. Of organic acids, citric acid was the most abundant, followed by acetic acid and lactic acid. Fatty acid composition was high in the order of linoleic acid (50.82~54.51%), oleic acid (17.76%~22.10%) and plamitic acid(12.13~13.79%). There were no significant difference in compositions of organic acids and fatty acids of chungkugjang. Major volatile compounds of SBC were indole , 2-5-dimethyl pyrazine and trimethyl pyrazine. Contents of alkyl pyrazines that contribute the characteristic aroma and flavor of SBC added and fermented with kiwi and radish homogenate were 3 times lower than those of SC. Uracil and UMP were major nucleic acie-drlated compounds in all four chungkugjangs. Contents of the other nucleic acid-related compounds were a similar trend in all chungkugjangs.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.160-166
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• 1995

Visitors to Chuwangsan National Park were survayed from August 3 to 5 n 1994. During this time, 346 visitors were contacted. Of those individuals, 65% were males. 63% of respondents reported that they had gone as far as college. 48% were 20 years of age. 97% of the survey respondents had experience to visit other national parks. The largest percentage of respondents were reported that they visited Chuwangsan Nat'1 Park for enjoying natural landscape. In group type, 50% were traveling with their family and 36% with their friends. In activity characteristics, 51% were day-time visitors, and 18% mentioned carrying in their on food. Generally most respondents were very interested in the environmental problem in national parks. The majority of visitors perceived that the environment of Chuwangsan Nat'1 Park were good enough. In six types of normative violations, the major reasons of littering were unintentional violation and releaser-cue violation. Most respondents were not likely to intervene to stop other visitors' depreciative behavior (Bystander intervention behavior). In two dilemmas, the more likely the intention to obey a regulation the less likely the intention to disobey a regulation, and vice-versa.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.90-90
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• 2003

물김치는 발효 중 국물에 생성된 젖산을 비롯한 각종 유기산과 이산화탄소가 주는 독특한 신선미와 상쾌한 탄산미 그리고 배추나 무의 아삭아삭한 조직감 때문에 즐겨 먹는 김치의 종류이다. 일반 배추로 담근 물김치가 무색인데 비해, 안토시아닌 색소를 함유한 자색 양배추를 주재료로 물김치를 담그면 발효됨에 따라 유기산이 생성되어 pH가 낮아짐에 따라 색소가 안정화되어 시각적으로 아름다운 색을 띌 것으로 생각된다. 따라서 본 실험에서는 배추, 흰양배추, 적색양배추로 물김치를 담그어 숙성되는 동안의 이화학적, 관능적 특성을 분석하였다. (중략)

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.328-333
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• 2003

When the extract of the medicinal plants, Kaempferia galanga L., Zanthoxylum bungeanum, Eugenia caryophyllata, Foeniculum vulgare, was added to Naengmyeon broth with the concentration of 0.1% and 0.3% each, its effect during the preservation time of broth was investigated. pH of the extract-added broth was lower than control at the initial, but higher after 72 hours of preservation, which showed that when it added 0.1% and 0.3% of extract to the broth, pH of Kaempferia galanga L. was 4.92 and 5.08 respectively, whereas control was 4.60. Titratable acidity was lowered after 48 hours and also Kaempferia galanga L. showed the lowest acidity with 0.66 for adding 0.1% of its extract and 0.55 for 0.3% of adding, but control was 0.89 at the time of 90 hours of preservation, and then it showed to be lowered in the order of Zanthoxylum bungeanum, Eugenia caryophyllata and Foeniculum vuigare. Turbidity of each broth added the extracts of four of the medicinal plants was 7.5∼7.9 and 7.9∼8.2, respectively for 0.1% and 0.3% of concentration at the initial, but it began to lower and 90 hours later it was 8.8∼9.5 and 8.7∼9.0 respectively, whereas control was 10.8. Total viable cells(TVC) and coliform bacteria(CB) were increased with great at the 72 hours of preservation time, and Kaempferia galanga L. was the most effective, which when control was 4.8${\times}$10 CFU/ml at 72 hours, TVC was 1.7${\times}$10 CFU/ml for the addition of 0.1% of extract and 0.9${\times}$10 CFU/ml for 0.3%. CB was 3.2${\times}$10 CFU/ml for 0.1% and 1.7${\times}$10 CFU/ml for 0.3% respectively and 6.0 ${\times}$ 10 CFU/ml for control at the time of 72 hours, and it was lowered in the order of Zanthoxylum bungeanum, Eugenia caryophyllata and Foeniculum vulgare. Volatile basic nitrogen content detected that control was 2.67mg% at first, and then increased to 3.96mg% at 90 hours of preservation, but the broth added with the extract of Kaempferia galanga L. was 2.58mg% for 0.1% and 2.47mg% for 0.3% at the initial, and at 90 hours it was 3.64mg% and 3.33mg% respectively. The results of adding the extracts of four medicinal plants for the improvement of the preservation time of Naengmyeon broth, were that the most effective medicinal plant was Kaempferia galanga L. and the antimicrobial activity of the medicinal plant extracts for Naengmyeon broth was highly effective after 3 days of preservation time.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.526-535
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• 1988

To estimate the effect of preventing the Maillard reaction between casein and glucose coated by freeze drying with corn starch slurry or mixture slurry of corn starch and sucrose, the reactants were treated into five groups of nonbrowning material(control), uncoated browning material, browning material coated casein alone with starch slurry, browning material coated both of reactants with starch slurry and browning material coated both of reactants with mixtrue slurry. All samples had a moisture content of about 15%. Browning reaction was carried out by storage for 30 days at $37^{\circ}C$, 67% RH. In vitro available lysine contents were decreased by the browning regardless of coating the reactants and were higher about 20.5% in the browning materials coated with mixture slurry than in the uncoated browning materials. Fructosyl-lysine contents were increased about tenfold by the browning regardless of coating and were decreased about 15.8% in the browning materials coated with mixture slurry as compare with the uncoated browning materials. The materials showing the greatest resistance to the browning reaction in the coated materials were those in which both of reactants were coated with the mixture slurry of corn starch and sucrose.

• Food Science and Preservation
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• v.21 no.5
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• pp.757-765
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• 2014

Campbell Early grapes were spontaneously fermented with and without sulfiting to investigate the effect of sulfiting on the fermentation characteristics and physicochemical properties of Campbell Early wine. During the fermentation, the increase in the alcohol and the decrease in the soluble solid contents were faster without sulfiting, as was the increase in the yeast viable counts compared to those with sulfiting. However, the final alcohol and soluble solid contents reached similar levels with and without sulfiting. The PCR-RFLP analysis of the yeast in the ITS I-5.8S-ITS II region revealed that the increase in the S. cerevisiae was faster in the initial fermentation stage and reached a slightly higher level in the late stage with sulfiting than without sulfiting. The wine prepared after the fermentation with sulfiting showed higher malic and tartaric acid contents, as well as methanol, acetaldehyde, and n-propanol contents, than the wine prepared without sulfiting. The ethyl acetate content of the wine without sulfiting was 375.5 mg/L, which was 5.3 times higher than that (70.5 mg/L) with sulfiting. In the sensory evaluation, the wine without sulfiting obtained higher scores in flavor and overall preference than that with sulfiting.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.666-672
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• 2011

This study examined the different growth rate of larval salamander Hynobius leechii by the predation risk. We collected salamander's eggs from Mountain Inwang. Eggs were treated by two different conditions: (1) cue - which had a predation risk three times a day; (2) no cue - which had no predation risk. Predation risk was conducted by using chemical cue from Chinese minnows. The chemical cue treatment started from the next day after the collection and ended one week after the hatching. Between the first week and the second week after the hatching we fed salamander larvae with tubifex ad. libitium. After the treatment phase, we measured snout - vent length of the each larva on the first week and the second week after the hatching. The results showed that there was a significant difference in the growth rate by the predation risk. From these results we found that predation risk can cause the different growth rate to the larval salamander and these changes could be affect their mortality.

• Journal of Life Science
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• v.18 no.11
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• pp.1561-1569
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• 2008

This study was conducted to investigate the effects of steam flaking of corn grains on in situ dry matter degradability in the rumen and contents of mycotoxins (aflatoxin, ochratoxin) during storage. Yellow dent corns imported from USA and India were flaked, and stored for 8 weeks under the standard temperature and pressure (STP; $25^{\circ}C$/ 1 atm.). Experimental treatments were composed of four corn grains (untreated-USA corn, USCW; steam flaked-USA corn, USCF; untreated-India corn, IDCW; steam flaked-India corn, IDCF) with 4 replications according to 9 storage periods (0, 1, 2, 3, 4, 5, 6, 7, 8 week). Two ruminally cannulated Holstein bulls were used for in situ trial. Pathogen contamination trial was performed by comparing the mycotoxin contents in corns during storage periods. Dry matter disappearance rate in the rumen was about 3.0 to 44.1% higher (P<0.05) for USCW than IDCW, but was not difference between USCF and IDCF. With steam flaking of corn, dry matter degradability in the rumen was significantly (P<0.05) increased in corn from India, but was not affected in corn from USA. Aflatoxin content was very low level in corns from USA and steam flaked corns, but was higher than the tolerance limit of domestic aflatoxin content regulation when IDCW was stored over 6 week under STP. Ochratoxin content was low level in all treatments. From above results, it is reasonable that the corn imported from India might be flaked for enhance the ruminal DM degradability and safe from aflatoxin pathogen.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.129-135
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• 2013

Japanese larch (Larix leptolepis) has been extensively planted in Korea as a reforestation species but their supply has been a major bottleneck due to sporadic natural seed production. In this study, stem girdling was applied to 32-year-old grafted Japanese larches, resulting in significantly enhanced seed production compared to the controls. Stem girdling induced about 4 times higher cone production than that of controls in the Japanese larch seed orchard. Time-dependent metabolic alterations after girdling were investigated by stable isotope ratio mass spectrometer, HPLC, and GC-MS analysis. In girdled trees, the contents of total nitrogen, sucrose, and total free amino acids were significantly higher than the non-girdled trees at the flowering differentiation season (from July to August). Moreover, the numbers of female strobilus per tree were positively correlated with the contents of both total nitrogen (r=0.765, p<0.01) and total amino acids (r=0.802, p<0.01) in the bark being collected at the flowering differentiation time (August 20). Interestingly, the levels of various individual amino acids at the flowering differentiation times, such as aspartic acid, glutamic acid, glycine, serine, and cysteine, were also significantly correlated (p<0.05) with the numbers of strobilus, suggesting that those amino acids might be involved in the induction of female strobilus formation of Japanese larches.