• Journal of Korean Society of Environmental Engineers
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• v.33 no.6
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• pp.413-419
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• 2011

Nanoscale zero-valent iron (NZVI) particles were tested as remediation media for groundwater contaminated by organic pollutants (e.g., TCE, trichloroethylene). The contaminated groundwater contained anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, and $HCO_3^-$) and natural organic matter (NOM). Treatability of commercial NZVI particles (NANOFER 25, Nanoiron, Czech) was tested by using a synthetic groundwater and the field groundwater samples. More than 95% of 1.8 mM TCE was removed within 20 hours with a NZVI dosage of 25 g/L ($k=0.15hr^{-1}$). Repetitive degradation experiments revealed that the removal capacity of NANOFER 25 was 0.19 mmole TCE/g NZVI. TCE degradation reactions were not substantially affected by the presence of each anion with concentrations as high as 100 times the average field concentrations. However, when the four anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, $HCO_3^-$) were present simultaneously. the degradation reactivity and removal capacity were decreased by 60% ($k=0.069hr^{-1}$) and 10%, respectively. The k value of TCE degradation in the presence of NZVI (25 g/L) with dissovled organic carbon of 2.5 mg/L was also decreased by 84% ($k=0.025hr^{-1}$). In the experiments with the field groundwater, more than 90% of $1.8{\mu}M$ TCE, which is the concentration of TCE at the source zone, was removed within 10 hours with a NANOFER 25 dosage of 25 g/L. The results imply that the contaminated groundwater can effectively be treated by NANOFER 25 with more information on the hydrogeology of the site.

• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.111-118
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• 2014

The electrochemical properties using the cells assembled with the synthesized $LiCoO_2$(LCO) were evaluated in this study. The LCO was synthesized from high-purity cobalt sulfate($CoSO_4$) which is recovered from the cathode scrap in the wastes lithium ion secondary battery(LIB). The leaching process for dissolving the metallic elements from the LCO scrap was controlled by the quantities of the sulfuric acid and hydrogen peroxide. The metal precipitation to remove the impurities was controlled by the pH value using the caustic soda. And also, D2EHPA and $CYANEX^{(R)}272$ were used in the solvent extraction process in order to remove the impurities again. The high-purity $CoSO_4$ solution was recovered by the processes mentioned above. We made the 6 wt.% $CoSO_4$ solution mixed with distilled water. And the 6 wt.% $CoSO_4$ solution was mixed with oxalic acid by the stirring method and dried in oven. $LiCoO_2$ as a cathode material for LIB was formed by the calcination after the drying and synthesis with the $Li_2CO_3$ powder. We assembled the cells using the $LiCoO_2$ powders and evaluated the electrochemical properties. And then, we confirmed possibility of the recyclability about the cathode materials for LIBs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.569-576
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• 2016

This study researched the effects of cooking methods on phytochemical-enriched thin rice porridge (RP) of three colors (red, yellow, and green). Each of the RPs was prepared by three cooking methods and retorted through two-steps (step 1, at $80^{\circ}C$ for 15 min; step 2, at $82^{\circ}C$ for 25 min) for pasteurization. Cooking method (CM) 1 involved heating a mixture of all ingredients while CM 2 involved addition of apple/beet (AB, red), sweet-pumpkin/cabbage (PC, yellow) or vitamin/pear (green) while heating rice flour and glutinous rice flour. CM 3 involved mixing pre-cooked fruits and vegetables with cooked thin RP. The viscosity of RP prepared by CM 1 was lower than those of other RPs (P<0.05). The result of colorimetric a value show that red and green color of AB and VP prepared by CM 2 and CM 3 were most vivid. Contents of phytochemicals and antioxidants were higher when RP was prepared by CM 2 and CM 3 compared to CM 1. ${\Delta}E$ values of PC showed no significant difference before and after pasteurization, whereas AB and VP were significantly different (P<0.05). Antioxidant activity after retorting was not significantly different from those of un-retorted RPs. The results of color, phytochemical content, and antioxidant activity show that CM 2 or CM 3 were considerably better than CM 1, whereas cooking method had no effect after two-step retorting. Therefore, uncomplicated cooking method such as CM 1 or CM 2 are suited for commercial production of RPs.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.334-341
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• 2001

Purpose: Ascorbic acid us known to act as an antioxidant. Therefore, it can be used in increasing the efficiency of radiochemical labeling of Technetium-99m setamibi by inhibition of oxidation of $Sn^{2+}$ at low concentration. We intended to estimate the efficiency of radiochemical labeling and the stability of the newly formed formulation when ascorbic acid was added to a commercial kit. Materials and Methods: Synthesis of sestamibi was performed according to Dong-A's patent procedure (No.10-2001-0012877). First, we undertook a study to evaluate the efficiency of radiochemical labeling of sestamibi containing ascorbic acid. The stability of the vials was assessed using either $7.5{\mu}g\;or\;75{\mu}g$ of ascorbic acid, added to commercial vials under the accelerated condition(Temp : $40^{\circ}C{\pm}2^{\circ}C$, Relative humidity : $75{\pm}5%$). Results: Sestamibi was synthesized in overall 35-40% yield over 5 steps from a commercially available methallyl chloride as a starling material. When ascorbic acid was added, the efficiency of radiochemical labeling was maintained compared to the vial with no ascorbic acid. The accelerated test showed that the addition of ascorbic acid inhibited the oxidation of $Sn^{2+}$ ion by antioxidation mechanism. Also, the efficiency of radiochemical labeling of this vial after 9 months was nearly the same as the starting point. Therefore, the storage period of the kit is likely to be extended. Taken together, it suggests that the addition of ascorbic acid as a stabilizer is desirable. Conclusion: To increase the stability of a sestamibi cold kit, it is desirable to add ascorbic acid as a stabilizer to the commercial formulation.

• Korean Journal of Remote Sensing
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• v.33 no.6_2
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• pp.1101-1118
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• 2017

Temperatures in urban areas are steadily rising due to rapid urbanization and on-going climate change. Since the spatial distribution of heat in a city varies by region, it is crucial to investigate detailed thermal characteristics of urban areas. Recently, many studies have been conducted to identify thermal characteristics of urban areas using satellite data. However,satellite data are not sufficient for precise analysis due to the trade-off of temporal and spatial resolutions.In this study, in order to examine the thermal characteristics of Daegu Metropolitan City during the summers between 2012 and 2016, Moderate Resolution Imaging Spectroradiometer (MODIS) daytime and nighttime land surface temperature (LST) data at 1 km spatial resolution were downscaled to a spatial resolution of 250 m using a machine learning method called random forest. Compared to the original 1 km LST, the downscaled 250 m LST showed a higher correlation between the proportion of impervious areas and mean land surface temperatures in Daegu by the administrative neighborhood unit. Hot spot analysis was then conducted using downscaled daytime and nighttime 250 m LST. The clustered hot spot areas for daytime and nighttime were compared and examined based on the land cover data provided by the Ministry of Environment. The high-value hot spots were relatively more clustered in industrial and commercial areas during the daytime and in residential areas at night. The thermal characterization of urban areas using the method proposed in this study is expected to contribute to the establishment of city and national security policies.

• Journal of Nutrition and Health
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• v.45 no.6
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• pp.541-551
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• 2012

In our previous work, we reported consumers' perceptions of body shape and weight control. In an ongoing effort, we analyzed the purchasing behavior, intake patterns, future purchasing decisions, and degree of satisfaction in individuals consuming dietary formula for weight control (DF) or heath/functional foods (HFFs) by using the same survey questions. Portfolio analysis for marketing strategy was also investigated. Subjects were divided into two groups according to consumption of DF or HFF during the previous year : DF group (n = 89) and HFF group (n = 110). Average intake frequency was $1.7{\pm}0.7$ per day for HFFs and $1.5{\pm}0.9$ per day for the DF, and the most prevalent form was pill (58.2%) for HFFs and bar (42.7%) for DF. Duration of intake was $3.1{\pm}2.3$ months for HFFs versus $3.9{\pm}3.5$ months for DF. The average degree of satisfaction was $3.6{\pm}0.6$ on a 5-point scale, meaning 'relatively satisfied'. For the weight control method to be used in the future, 44.5% of the HFF group selected 'HFFs' while 47.2% of the DF group selected 'DF', showing a tendency to use the current product type in the future. The average planned period for the intake was $3.8{\pm}3.7$ months for HFFs and $3.0{\pm}2.4$ months for DF (p < 0.05). The HFF group emphasized efficacy, functional ingredients of the products, reliable products, and higher satisfaction, whereas the DF group emphasized the added materials in addition to weight control effects.

• Korean Journal of Poultry Science
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• v.35 no.3
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• pp.283-290
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• 2008

The Siberian ginseng and Eucommia are a kind of medicinal plant with powerful anti-oxidant activity. An experiment was conducted to investigate the effect of Siberian ginseng leaf and Eucommia leaf at level of 0.5% and 1% per feed in Ross commercial broiler for 4 to 35 days of age on performance, organ weight, blood biochemical profiles and telomere quantity. Chickens consuming diets containing 1% Siberian ginseng had higher feed conversion ratio than the other treated chicken during experimental period whereas no significant differences were detected in body weight, weight gain and feed intake. The weight of bursa of fabricius was significantly increased in chickens with dietary supplementation compared with chickens fed control but this was not seen in liver, spleen and thymus. In blood biochemical profiles, chickens with dietary supplementation had higher concentration than chickens fed control in triglyceride, cholesterol and glucose. The concentration of aspartate aminotransferase, alanine aminotransferase, albumin and total protein, however, was not significantly different between dietary supplemented chickens and control chickens. The relative amount of telomeric DNA of lymphocytes in chickens with dietary supplementation was significantly higher than that of control chickens but the difference was not found in liver, heart and testis tissues. In conclusion, dietary supplementation of Siberian ginseng and Eucommia in broiler improved immune activity and telomere length without decreasing chicken growth performance.

• Journal of Mushroom
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• v.14 no.4
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• pp.142-154
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• 2016

Worldwide production of mushrooms has been increasing by 10-20% every year. Recently, Pleurotus eryngii and P. nebrodensis have become popular mushroom species for cultivation. In particular, China exceeded 8.7 million tons in 2002, which accounted for 71.5% of total world output. A similar trend was also observed in Korea. Two kinds of mushrooms-Gumji (金芝; Ganoderma) and Seoji-are described in the ancient book 'Samguksagi' (History of the three kingdoms; B.C 57~A.D 668; written by Bu Sik Kim in 1145) during the Korea-dynasty. Many kinds of mushrooms are also described in more than 17 ancient books during the Chosun-dynasty (1392~1910) in Korea. Approximately 200 commercial strains of 38 species of mushrooms were developed and distributed to cultivators. The somatic hybrid variety of oyster mushroom, 'Wonhyeong-neutari,' was developed by protoplast fusion, and distributed to growers in 1989. Further, the production of mushrooms as food was 199,829 metric tons, valued at 850 billion Korean Won (one trillion won if mushroom factory products are included) in 2015. In Korea, the major cultivated species are P. ostreatus, P. eryngii, Flammulina velutipes, Lentinula edodes, Agaricus bisporus, and Ganoderma lucidum, which account for 90% of the total production. Since mushroom export was initiated in 1960, the export and import of mushrooms have increased in Korea. Technology was developed for liquid spawn production, and automatic cultivation systems led to the reduction of production cost, resulting in the increase in mushroom export. However, some species were imported owing to high production costs for effective cultivation methods. In academia, RDA scientists have conducted mushroom genome projects since 1997. One of the main outcomes is the whole genome sequencing of Flammulina velutipes for molecular breeding. With regard to medicinal mushrooms, we have been conducting genome research on Cordyceps and its related species for developing functional foods. There are various kinds of beneficial substances in mushrooms; mushroom products, including pharmaceuticals, tonics, healthy beverages, functional biotransformants, and processed foods have also became available on the market. In addition, compost and feed can likewise be made from mushroom substrates after harvest.

• Journal of the Korean Society of Food Culture
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• v.14 no.4
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• pp.289-304
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• 1999

The purpose of this study was to examine the consumers' acceptance of irradiated foods according to sociodemographic characteristics and the factors to distinguish subjects with differential levels of their willingness to buy them. Data were collected from the 365 women living in Youngnam area by the self-administered questionnaire. The results from this study were as follows. First, consumers were concerned regarding food safety issues in general and particularly preservatives. Second, many subjects had not heard of the irradiated foods and showed wait-and-see attitude in the willingness to accept them. Consumers' willingness to purchase them were higher than any other cases if radiation would not remain in foods. Third, the results from the discriminant analyses showed that the concern toward food safety, perceived innovativeness, willingness to pay more for organic foods, and knowledge of irradiation were the factors to distinguish groups with differential levels of willingness to purchase the irradiated foods. The results from the study imply that accurate and scientific information about food irradiation should be given to the consumers.

• Journal of Nutrition and Health
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• v.44 no.3
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• pp.243-254
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• 2011

The purpose of this study was to investigate the general characteristics, body shape, and perceptions of weight control in individuals consuming functional health foods and weight-control foods. The survey was conducted between April 15 and June 17, 2010 among 199 (57 males and 142 females; age range, 25-45 years) in Seoul and Gyeonggi-do, who experienced eating functional health foods or weight control foods during the past year (June 2009 to June 2010). The subjects were divided into a weight-control food group (89 adults) and a functional health food group (110 adults). The subjects were comprised of a high proportion of aged (average age, $34.2{\pm}5.9$ years), graduates (71.9%), and married (65.8%) individuals. In the weight control food group, gender, age, and educational background were similar and the ratios of service/technical employees, college students, and normal-weight individuals [body mass index (BMI), < 23] were high. BMI was significantly different by gender (p < 0.001), age (p < 0.01), marital status (p < 0.001), and job type (p < 0.001). Self-perceived health status showed a higher response for "in good health" in the 35-44 year old group than that in the 25-34 year old group (p < 0.05). Male group satisfaction for body shape was significantly higher than that in the female group. The main reason for going on a diet was significantly different by gender (p < 0.05) and BMI (p < 0.01). The main motives for dieting were "because I am not at an ideal weight" and "because of the social atmosphere and the attention of others " in men, but "can't wear the clothes I want" in women (p < 0.01). The most preferable product type related to the two groups was significantly different by job (p < 0.001) and BMI (p < 0.05). However, no significant differences were observed for questions about body shape perception and weight control. Consumers who had different general characteristics and used diet products perceived body shape and weight control differently. Additionally, no meaningful differences were observed when the results were categorized by product type, except job and BMI, but the distribution of consumer characteristics showed different tendencies. These results can be utilized as basic data for developing new diet products to help people control their weight more scientifically and appropriately in the future.