• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.182-189
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• 1980

This experiment was carried out to study on methods of processing the fruit base which is to be used for preparing the fruit yoghurts. Common fruits were compared and peach was chosen among them for this purpose by determing the rate of decrease in hardness during the process of cooking. The maturity, temperature of cooking and methods of peeling were tested to maintain the desirable hardness during the process, and the effects of metallic ion addition on the hardness of the flesh were also studied. The results obtained were as follows. 1. The peaches were keeping the most stable texture during cooking, among common fruits, however the hardness of apples were decreased markedly. Rate of decreases in the flesh hardness were high during the initial stages of cooking then slowered in all fruits tested. 2. Flesh hardness of the peaches were largely affected by the temperature of cooking. And the texture of freeze-stored fruits was severly damaged during thawing, so that could be used only for the limited purposes such as for stirred-type yoghurt. 3. Divalent matallic ions, especially calcium ion, were effective for supporting the flesh hardness of peaches during cooking. 4. The optimal concentration of calcium chloride addition was 0.3%, and this resulted in its final concentration in the product under the legal dosage without any subsquent changes in colour and flavor. 5. The effects of calcium chloride addition were greater in the froms of dices than in those of slices, and in overmature fleshs than in immature ones. 6. Treatment of calcium chloride by soaking the slices or dices of lye-peeled peaches in 0.3% solution was found to be adaptable for the practical process.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.268-275
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• 2013

This study was performed to investigate the antioxidant activity of cherry added into meat products. Water and methanol were used to extract the antioxidant compounds from cherry. Total phenolic compounds of the methanol and water extract of cherry were 2.17 g/100 g and 2.77 g/100 g, respectively. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of methanol extract showed similar activities to those with ascorbic acid at all concentrations (from 0.1% to 2.0%). Especially, water extract of cherry showed similar activity to those of ascorbic acid (AA), and methanol extract, when 2% of cherry extract was added. The reducing power of cherry was not comparable to those with AA, however no differences in reducing power were observed between the water and methanol extract. The iron chelating ability of cherry was observed in the range of 17.8-94.0% at both water and methanol extracts. An increased iron chelating ability was observed with increased concentration up to 2%. Iron chelating ability for water extract of cherry tended to be lower than those with methanol extract. After pork patties were manufactured with methanol extract of cherry at 0.5 and 1.0%, physicochemical properties, lipid oxidation and microbial changes of patties were measured. The addition of methanol extract of cherry reduced pH, brightness, redness, yellowness and thiobarbituric acid reactive substance (TBARS). During 14 d of storage, pH, TBARS and microbial counts were increased, while redness and yellowness values were decreased. Since the addition of methanol extract of cherry lowered TBARS during storage, it could be used as a natural antioxidant in meat products.

• Journal of Life Science
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• v.17 no.12
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• pp.1660-1668
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• 2007

The non-ionic surfactant (NIS) Tween 80 was evaluated for its ability to influence invitro cumulative gas production, dry matter digestibility, cellulolytic enzyme activities, anaerobic microbial growth rates, and adhesion to substrates by mixed rumen microorganisms on rice straw, alfalfa hay, cellulose filter paper and tall fescue hay. The addition of NIS Tween 80 at a level of 0.05% increased significantly (P<0.05) in vitro DM digestibility, cumulative gas production, microbial growth rate and cellulolytic enzyme activity from all of substrates used in this study. In vitro cumulative gas production from the NIS-treated substrates; rice straw, alfalfa hay, filter paper and tall fescue hay was significantly (P<0.05) improved by 274.8, 235.2, 231.1 and 719.5% compared with the control, when substrates were incubated for 48 hr in vitro. The addition of 0.05% NIS Tween 80 to cultures growing on alfalfa hay resulted in a significant increase in CMCase (38.1%), xylanase (121.4%), Avicelase (not changed) and amylase (38.2%) activities after 36 h incubation. These results indicated that the addition of 0.05% Tween 80 could greatly stimulate the release of some kinds of cellulolytic enzymes without decreasing cell growth rate in contrast to trends reported with aerobic microorganism. Our SEM observation showed that NIS Tween. 80 did not influence the microbial adhesion to substrates used in the study. Present data clearly show that improved gas production, DM digestibility and cellulolytic enzyme activity by Tween 80 is not due to increased bacterial adhesion on the substrates.

• Journal of the Korean Electrochemical Society
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• v.22 no.1
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• pp.36-42
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• 2019

A macroporous Sn thick film as a high capacity negative electrode for a lithium ion secondary battery was prepared by using a chemical etching method using nitric acid for a Sn film having a thickness of $52{\mu}m$. The porous Sn thick film greatly reduced the over-voltage for the alloying reaction with lithium by the increased reaction area. At the same time. The porous structure of active Sn film plays a part in the buffer and reduces the damage by the volume change during cycles. Since the porous Sn thick film electrode does not require the use of the binder and the conductive carbon black, it has substantially larger energy density. As the concentration of nitric acid in etching solution increased, the degree of the etching increased. The etching of the Sn film effectively proceeded with nitric acid of 3 M concentration or more. The porous Sn film could not be recovered because the most of Sn was eluted within 60 seconds by the rapid etching rate in the 5 M nitric acid. In the case of etching with 4 M nitric acid for 60 seconds, the appropriate porous Sn film was formed with 48.9% of weight loss and 40.3% of thickness change during chemical acid etching process. As the degree of etching of Sn film increased, the electrochemical activity and the reversible capacity for the lithium storage of the Sn film electrode were increased. The highest reversible specific capacity of 650 mAh/g was achieved at the etching condition with 4 M nitric acid. The porous Sn film electrode showed better cycle performance than the conventional electrode using a Sn powder.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.781-797
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• 2023

Recently, there has been a rapid response from mineral-demanding countries for securing critical minerals in a high tech industries. Graphite, while overwhelmingly dominated by China in production, is changing in global supply due to the exponential growth in EV battery sector, with active exploration in East Africa. Rare earth elements are essential raw materials widely used in advanced industries. Globally, there are ongoing developments in the production of REEs from three main deposit types: carbonatite, laterite, and ion-adsorption clay types. While China's production has decreased somewhat, it still maintains overwhelming dominance in this sector. Recent changes over the past few years include the rapid emergence of Myanmar and increased production in Vietnam. Nickel has been used in various chemical and metal industries for a long time, but recently, its significance in the market has been increasing, particularly in the battery sector. Worldwide, nickel deposits can be broadly classified into two types: laterite-type, which are derived from ultramafic rocks, and ultramafic hosted sulfide-type. It is predicted that the development of sulfide-type, primarily in Australia, will continue to grow, while the development of laterite-type is expected to be promoted in Indonesia. This is largely driven by the growing demand for nickel in response to the demand for lithium-ion batteries. The global lithium ores are produced in three main types: brine lake (78%), rock/mineral (19%), and clay types (3%). Rock/mineral type has a slightly higher grade compared to brine lake type, but they are less abundant. Chile, Argentina, and the United States primarily produce lithium from brine lake deposits, while Australia and China extract lithium from both brine lake and rock/mineral sources. Canada, on the other hand, exclusively produces lithium from rock/mineral type. Vanadium has traditionally been used in steel alloys, accounting for approximately 90% of its usage. However, there is a growing trend in the use for vanadium redox flow batteries, particularly for large-scale energy storage applications. The global sources of vanadium can be broadly categorized into two main types: vanadium contained in iron ore (81%) produced from mines and vanadium recovered from by-products (secondary sources, 18%). The primary source, accounting for 81%, is vanadium-iron ores, with 70% derived from vanadium slag in the steel making process and 30% from ore mined in primary sources. Intermediate vanadium oxides are manufactured from these sources. Vanadium deposits are classified into four types: vanadiferous titanomagnetite (VTM), sandstone-hosted, shale-hosted, and vanadate types. Currently, only the VTM-type ore is being produced.

• Food Science and Preservation
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• v.21 no.2
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• pp.193-198
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• 2014

The quality and antioxidative characteristics of drinks prepared with different mixing ratios of black garlic and Oenanthe javanica DC., BD-1 (black garlic only), BD-2 (black garlic:Oenanthe javanica DC.=2:1), BD-3 (black garlic:Oenanthe javanica DC.=1:1), and BD-4 (black garlic:Oenanthe javanica DC.=1:2), were studied. The pH increased with the increasing concentration of Oenanthe javanica DC. extract in all the tested drinks, but the sugar contents decreased. The total polyphenol contents of the drinks were 28.48 ${\mu}g/mL$ (BD-1), 41.91 ${\mu}g/mL$ (BD-2), 42.36 ${\mu}g/mL$ (BD-3), and 46.96 ${\mu}g/mL$ (BD-4). The SOD-like activity was highest for BD-4 (18.60%), followed by BD-3 (15.53%), BD-2 (12.53%), and BD-1 (10.27%). The thiobarbituric acid reactive substances (TBARS) was highest for BD-4 (52.51%), followed by BD-3 (45.70%), BD-2 (39.44%), and BD-1 (28.72%). The ferrous ion chelating activity increased with the increasing concentration of Oenanthe javanica DC extract, and BD-4 showed the best activities among all the tested drinks. The water-soluble vitamin content (vitamins B1, B2, B6, and C) of BD-4 (1197.77 ${\mu}g/mL$) was higher than those of the other drinks (BD-1, 213.02 ${\mu}g/mL$; BD-2, 477.87 ${\mu}g/mL$; BD-3, 914.72 ${\mu}g/mL$), and the vitamin C (806.21 ${\mu}g/mL$) content of the water-soluble vitamins at BD-4 was higher than those of vitamins B1 (68.04 ${\mu}g/mL$), B2 (312.51 ${\mu}g/mL$), and B6 (11.01 ${\mu}g/mL$). BD-4 showed the best score in the sensory evaluations, such as in the evaluation of the color, flavor, taste, and overall acceptability.

• Food Science and Preservation
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• v.21 no.2
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• pp.276-285
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• 2014

The purpose of this study was to develop a new fermented product (named as Cheonggeumjang) using Sigumjang, Cheonggukjang and Oak mushroom. This study was conducted to evaluate the effects of Sigumjang, Cheonggukjang, and Cheonggeumjang, which were mixed in a different ratio as A (Sigumjang: Cheonggukjang = 1:2), B (Sigumjang: Cheonggukjang = 1:1) and C (Sigumjang: Cheonggukjang = 2 : 1). Then, the functions and physicochemical properties of products were investigated. We found that the crude protein content in Cheonggeumjang was higher than in Sigumjang whereas fat and calories content was less than that of Cheonggukjang. Free sugar content in Cheonggeumjang C 5.8681 g/100g was the highest. Moroever, Cheonggeumjang C and Sigumjang has an antioxidant activities. The electron donating capacity, SOD like activity and the inhibitory effect on xanthine oxidase of these two were significantly high than other group. Fat rancidity is promoted in the presence of metal ion, Cheonggeumjang group has higher inhibitory effect on $Fe^{2+}$ion than on $Cu^{2+}$ ion. The rancidity of fat is also increased by reactive oxygens species, Cheonggeumjang group inhibited $H_2O_2$ in higher extent than $KO_2$. Also, ${\alpha}$-glucosidase inhibition activity of Cheonggeumjang C in all of the concentrations (300 ppm, 500 ppm and 700 ppm) is higher than other groups. In sensory evaluation, Cheonggeumjang C groups is ranked significantly higher than the other groups while considering color, flavor, taste and the overall acceptability. Taken together, the results of this study suggest that Cheonggeumjang is best ingredient for increasing the consumer acceptability and functionality.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.3
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• pp.211-221
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• 2017

This study was performed to investigate the functional properties and characteristics of Dolnamul (Sedum sarmentosum) as a cosmetic ingredient. Lyophilized sedum powder was extracted with ethanol and stored at $-20^{\circ}C$ for the following experiments. Total polyphenol compounds of the ethanol extract of sedum (SE) was $27.98{\pm}0.34g/kg$(dry weight): epicatechin ($162.14{\pm}5.07mg/kg$), epigallocatechin ($55.99{\pm}2.49mg/kg$), and kaempferol ($47.96{\pm}3.02mg/kg$) were contained in the SE. The SE had organic radical scavenging capacity ($78.43{\pm}1.08%$) and metal reducing power (FRAP value $2.54{\pm}0.12$). FTC and TBARS assays confirmed that the SE inhibited the early stage of lipid peroxidation ($62.03{\pm}0.38%$) as well as the final stage of lipid peroxidation ($55.36{\pm}2.05%$), respectively. The SE (5 mg/mL, dry weight) was proved to have antibacterial effect on the growth of Propionibacterium acnes. The inhibitory percentages of the SE on elastase and collagenase activities were $38.94{\pm}7.09%$ and $78.94{\pm}2.49%$, respectively. Compare to the control group, the SE treated group induced an increase of Col3A1 expression and collagen production ($58.11{\pm}1.07%$). The oil in water emulsion (0.5% SE adding group) showed pH 6.88 and 1.47 g/mL of density. The hardness changes of the SE adding emulsions were not detected during the stored periods at various temperatures ($-20-45^{\circ}C$) for four weeks. It is considered that the SE has antibacterial, antioxidant, and antiaging activities.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.215-220
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• 2008

Rahnella aquatilis AY2000 has an unique characteristic which produces an anti-yeast substance (AYS). The AYS of the strain AY2000 was always secreted on agar plate, however, its activity in liquid culture was labile upon storage of the medium. In this paper, cultural conditions of the strain AY2000 for the AYS production were investigated in liquid culture, and minimal inhibitory concentration (MIC) against Saccharomyces cerevisiae was determined for the AYS activity. MIC of the AYS cultured in PYG broth at $^25{\circ}C$ for 24 hr was $23.5{\mu}g/mL$, however, that in MYCS (pH 5.5) broth at the same condition was $15.5{\mu}g/mL$. The activity of the AYS had increased rather in MYCS broth excluded $NH_4$-citrate than in the same broth contained $NH_4$-citrate, and MIC of the AYS produced in MYCS broth without $NH_4$-citrate was $15.5{\mu}g/mL$. When the strain AY2000 was maintained in MYCS broth without $NH_4$-citrate but added $100{\mu}M$ $FeCl_3$, the activity of the AYS had increased and its MIC was $7.8{\mu}g/mL$. MIC of the AYS was $7.8{\mu}g/mL$ after the strain AY2000 was cultured in MYCS broth containing $100{\mu}M$ $FeCl_3$ without $NH_4$-citrate, however, its MIC was $31.3{\mu}g/mL$ after 48-60 hr culture in the same broth.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.1-10
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• 2005

The purpose of this study was to evaluate the potential of a gamma irradiation to decompose 2,4,6-trinitrotoluene(TNT) in an aqueous solution. The decomposition reaction of TNT by gamma irradiation was a pseudo first-order kinetic over the applied initial concentrations($25{\sim}100mg/L$). The dose constant was strongly dependent on the initial TNT concentration. The removal of TNT was more efficient at pH below 3 and at pH above 11 than at neutral pH(pH 5-9). The required irradiation dose to remove over 99% of TNT was 40, 80 and 10 kGy, individually at pH 2, 7 and 13. The dose constant was increased by 1.6 fold and over 15.6 fold at pH 2 and 13, respectively, when compared with that at pH 7 When irradiation dose of 200 kGy was applied, the removal efficiencies of TOC were 91, 46 and 53% at pH 2, 7 and 13, respectively. Ammonia and nitrate were detected as the main nitrogen byproducts of TNT and glyoxalic acid and oxalic acid were detected as organic byproducts. The results showed that a gamma irradiation was an attractive method for the decomposition of TNT in an aqueous solution. However, regarding the application of high energy radiation for the TNT decomposition and mineralization, an application of an acidic pH below 3 to the solution before irradiation should be considered.