• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.375-383
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• 2020

BACKGROUND: Bisphenol A (BPA) is a chemical widely used in polycarbonate plastics, epoxy resins. BPA is an endocrine disruptor. Residue of BPA in agricultural environments is a major concern. The objective of this study was to understand the characteristics of the uptake and distribution of BPA and its metabolites introduced into the agricultural environment to crops, and to use it as basic data for further research on reduction of BPA in agricultural products. METHODS AND RESULTS: This study established the analysis method of BPA and its metabolites in soil and crops, and estimated the intake of BPA and its metabolites from lettuce (Lactuca sativa) grown in sandy loam and loam soil, which are representative soils in Korea. The two major metabolites of BPA were 4-hydroxyacetophenone (4-HAP) and 4-hydroxybenzoic acid (4-HBA). BPA, 4-HAP and 4-HBA have been analyzed by using liquid chromatography tandem mass spectrometry (LC-MS/MS). These substances were detected in sandy loam and loam soil, indicating that certain portions of BPA were converted to 4-HAP and 4-HBA in the soil; however, it was observed that only 4-HBA migrated to lettuce through the roots into crops. CONCLUSION: The uptake residues showed the BPA and 4-HAP were not detected in lettuces grown on sandy loam (SL) and loam (L) soil treatments that were applied with of 10 ng/g, 50 ng/kg and 500 ng/g of BPA. However, the 4-HBA was detected at the level of 7 ng/g and 11 ng/g in the lettuce grown in sandy loam and loam soil that were treated with the 500 ng/g of BPA, respectively, while the 8 ng/g of 4-HBA was measured in the lettuce cultivated in the loam that was treated with 100 ng/g of BPA. This result presents that the BPA persisting in the soil of the pot was absorbed through the lettuce roots and then distributed in the lettuce leaves at the converted form of 4-HBA, what is the oxidative metabolite of BPA.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.1-8
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• 2022

With the spread of COVID-19 worldwide, non-face-to-face services have grown rapidly, but at the same time, the problem of plastic waste is getting worse. Accordingly, eco-friendly policies such as carbon neutrality and sustainable circular economy are being promoted worldwide. Due to the high demand for eco-friendly products, the packaging industry is trying to develop eco-friendly packaging materials using PLA and PBAT and create new business models. On the other hand, Ulva australis occurs in large quantities in the southern seas of Korea and off the coast of Jeju Island, causing marine environmental problems. In this study, lactic acid was produced through dilute acid pretreatment, enzymatic saccharification, and fermentation processes to utilize Ulva australis as a new alternative energy raw material. In general, seaweeds vary in carbohydrate content and sugar composition depending on the species, harvest location, and time. Seaweed is mainly composed of polysaccharides such as cellulose, alginate, mannan, and xylan, but does not contain lignin. It is difficult to expect high extraction yield of the complex polysaccharide constituting Ulva australis with only one process. However, the fusion process of dilute acid and enzymatic saccharification presented in this study can extract most of the sugars contained in Ulva australis. Therefore, the fusion process is considered to be able to expect high lactic acid production yield when a commercial-scale production process is established.

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.177-188
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• 1993

This study was performed to find out the reasonable sexing methods In the chicken, obtain the basic information for the mechanisms related to chicken sexual differentiation and identify the genes which known to involved in chicken sex differentiation. The chromosome analysis of chicken embryonic fibroblast was a simple method to determine sex of chicken by means of Z and W chromosome identification. The bands of female chicken genomic DNA digested with Xho Ⅰ and Eco RI restriction endonuclease showed to be useful in direct sex determination and these repetitive sequences of Xho Ⅰ and Eco RI families were proposed to be very homologous in their sequences by colony hybridization analysis. Seven of 150 random primers were selected to amplify the W chromosome-specific band by using arbitrary primed PCR and three of them were useful to identify the sex of chicken. To identify the sex differentiation genes in the chicken, PCR for the amplification of ZFY and SRY sequences was performed. ZFY and SRY sequences were amplified successfully in the chicken genome, implying that chicken genome might have the sex-related conserved sequences similar to mammalian ones. The PCR products of ZFY amplification were the same in both sexes, suggesting that these sequences may be located on autosome or Z chromosome. The profile of PCR amplification for SRY sequences showed variation between sexes, but this result was not enough to specify whether the SRY gene in chicken is on the autosome or sex chromosome.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.989-996
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• 2007

In this study, abiotic transformation of 1-naphthol(1-NP) via oxidative-coupling reaction and its reaction products were investigated in the presence of Mn oxides. The reaction products were characterized for their relative polarity using solvent extraction experiment and reverse-phase HPLC, and for structure using CCMS and LC/MS, and for absorption characteristics using UV-Vis spectrometry. The reaction products present in aqueous phase were more polar than parent naphthol and comprised of 1,4-naphthoquinon(1,4-NPQ) and oligomers such as dimers and trimers. Hydrophilic component present in water phase after solvent$(CH_2Cl_2)$ extractions was identified as naphthol polymerized products having molecular weight(m/z) ranging from 400 to 2,000, and showed similar UV-Vis. absorption characteristics to that of foil fulvic acid. Transformation of 1,4-NPQ, which is non-reactive to Mn oxide, to the polymerized products via cross-coupling reaction in the presence of 1-NP was also verified. In this experimental conditions(20.5 mg/L, 1-NP, 2.5 g/L $MnO_2$, pH 5), the transformation of 1-NP into the oligomers and polymerized products were about 83% of initial 1-NP concentrations, and more than 30% of the reaction products was estimated to be water insoluble fractions, not extracted by $H_2O$ methanol. Results from this study suggest that Mn oxide-mediated treatment of naphthol contaminated soils can achieve risk reduction through the formation of oligomers md polymer precipitation.

• Advances in concrete construction
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• v.9 no.3
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• pp.279-287
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• 2020

This paper focuses on the engineering properties of Bentonite-Cement-Sodium silicate (BCS) grout, which was prepared by partially replacing the ordinary Portland cement in Cement-Sodium silicate grout with lithium bentonite (Li-bent) and sodium bentonite (Na-bent), respectively. The effect of different Water-to-Solid ratio (W/S) and various replacement percentages of bentonite on the apparent viscosity, bleeding, setting time, and early compressive strength of BCS grout were investigated. The XRD method was used to detect its hydration products. The results showed that both bentonites played a positive role in the stability of BCS grout, increased its apparent viscosity. Na-bent prolonged the setting time of BCS, while 5% of Li-bent shortened the setting time of BCS. The XRD analysis indicated that the hydration products between the mixture containing Na-bent and Li-bent did not differ much. Using bentonite as supplementary cementitious material (SCM) to replace partial cement is a promising way to cut down on carbon dioxide emissions and to produce low-cost, eco-friendly, non-toxic, and water-resistant grout. In addition, Li-bent was superior to Na-bent in improving the strength and the thickening of BCS grouts.

• Journal of Families and Better Life
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• v.26 no.6
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• pp.193-207
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• 2008

This study analyzed the impact of the well-being trends and the attributes of the choice of the walnut-cookie on the consumer's purchasing intention. The results of this study would enhance newly revised product so that brand and product marketing strategy would be strengthened. This study also would contribute for the consumer related management through systematic and exploring research regarding consumers' expectation of products' values and trends. Specific results are as followings. Well-being oriented trends had various meanings such as "Commercial Well-being", "Eco-friendly Well-being", "Physical Well-being", and " Favors for leisure". Consumer's attributes of choice for the walnut-cookie were "Branding", "The Value of Traditional Food", "Environmental Position", and "The Function of Products". And the "Popularity", "Nutrition". and the "Service" were most preferred factors to be chosen. The multiple regression analysis was tried to test the impact of demographics, well-being trend, and the attributes of choice for walnut-cookie influence on the consumer's purchasing intention. The statistically significant factors were age, job, and leisure oriented consumer style of consumer's characteristics as well as corporation's brand strategy on a basis of marketing aspects. The younger groups, leisure pursing groups, and student groups showed the higher level of purchasing intention for the walnut-cookie compared to other groups.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.516.2-516
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• 1986

DNA subfragments, sopA, sopB, and sopC supporting stable maintenance of an oriC plasmid, were derived from mini-F plasmid DNA (EcoRI restriction fragment, f5) after digestion with restriction endonucleases, and cloned in vector plasmid pBR322. The recombinant plasmid obtained were introduced into E. coli KY7231 and E. coli CSR603, and proteins specified by the mini-F fragments were analysed by SDS-polyacrylamide gel electrophoresis. Two proteins encoded by the F fragments were detected, having molecular weights of 41,000 and 37.000. The sopA protein (41K) encoded by a plasmid pXX288 was observed in the cytoplasm, whereas the sopB protein (37K) encoded by a plasmid pXX157 was in the membrane fraction. There was no novel protein band detected in the cell with a plasmid pXX300, which contained sopC fragment. Gene products of a plasmid pXX167, which is comprised of sopA, sopB, and sopC, were not detectable. Fluorography after one and two dimensional gel electrophoresis of the lysates showed that these two proteins were overproduced in the cells which were allowed to incorporate radioactive amino acid after plasmid amplification by chloramphenicol treatment. The isoelectric points of the sopA and sepB proteins were 6.6 and 7.0, respectively.

• Journal of the Korean housing association
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• v.25 no.2
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• pp.121-130
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• 2014

This paper provides a social knowledge for pragmatic application guidelines of the interior finish materials within apartment houses, based on both the awareness of practitioners and as it applies to the realities. For this purpose, a series of the questionnaires survey on the awareness of interior finish materials in recently-constructed and remodeled apartment houses was performed, which has extended its probe into the awareness of architectural practitioners. The questionnaires asked practitioners how much they desire sustainable finish materials and the difference in various parties were analyzed and compared, formulating the pragmatic solution in the determination of interior finishes. Comparative analysis of the awareness of construction specialists, interior designer, architectural environmental researchers on environment-friendly finish materials showed that all parties were right to recognize the significance of sustainability in interior finishes. Practitioners believed that occupants must bear the additional expense for the environment-friendly finish products. Also, the results tell that the amount used of environment-friendly products increases as expertise on sustainability in interior finishes rises.

• Journal of Agricultural Extension & Community Development
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• v.7 no.1
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• pp.65-74
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• 2000

Agricultural extension services in YoungDong county, ChungBuk province have tried and changed many things to overcome difficult situations since localization of extension services in 1997. The county Rural Guidance Office changed the name of the office as county Agricultural Technology & Extension Center (ATEC), and has been operated as a service center for all people who need help in agriculture. The recent efforts of the ATEC have been placed on eco-friendly agriculture and sustainable agriculture for protecting the natural environment of the county as well as production of safe agricultural products. In order to overcame difficult situations under the IMF, the ATEC has tried to find new ways for the extension services because of reduced extension educators under the IMF restructuring. The followings were a few examples of many efforts in various fields to overcome difficult situations in the rural county; 1) The ATEC has supported services to produce safe and high quality agricultural products and to increase their high value through extension services for food processing. 2) The ATEC has opened experimental fields for farmers who want to learn new technologies to cultivate grapes, persimmons, apples and pests etc., specialty fruit trees in the county. 3) The ATEC has implemented many kinds of programs to improve the quality of the extension educators to serve better.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.6
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• pp.847-851
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• 2010

It was attempted to develop an auto part by over molding injection mold that produces precision products in high productivity with use of an eco-friendly TPE substitute material for NBR. NBR is currently used in motor gear cover, one of the key parts in motor module for auto doors. Gear cover is composed of plastics and rubber mostly today, which requires a two (2) step process for production using two presses of different types. A hot press is used at this time for forming the rubber, which has drawback of requiring a rather long forming time of 400 seconds for one forming process. Even though this difficulty is overcome by reducing production time through employment of multi-cavity molds, time for forming process must be shortened for improvement of the productivity eventually, and the existing method of insert injection for products that have been formed with plastic material must be outgrown. In this point of view, over molding injection using TPE has a big advantage. Forming time is shortened to 54 seconds, and working the two (2) processes in series by one (1) press could solve the durability problem caused by deflection of the plastics, not to mention shortening the process time. Enhancement of productivity by almost 80% and improvement in the accuracy of the product could thus be achieved.