• Clean Technology
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• v.19 no.1
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• pp.65-72
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• 2013

In this study, we investigated the activity of Pd and Cu co-incorporated on mesoporous silica support such as MCM-41 and SBA-15 for catalytic nitrate reduction in water. In pure hydrogen flow, nitrate concentration was gradually decreased with the reaction time, but nitrogen selectivity was too low due to very high pH of reaction medium after the reaction. In order to acquire high nitrogen selectivity, we utilized carbon dioxide as a pH buffer, which resulted in higher nitrogen selectivity (about 40%). For the above reaction conditions, Pd-Cu/MCM-41 showed better performance than Pd-Cu/SBA-15. The physicochemical properties of both catalysts were investigated to figure out the relationship between the characteristics of the catalysts and the catalytic activity on the catalytic nitrate reduction by $N_2$ adsoprtion-desorption, X-ray diffraction (XRD), $H_2$-temperature programmed reduction, X-ray photoelectron spectroscopy (XPS) techniques.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.959-963
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• 2000

Soy bean is one of the most common food material to cause food hypersensitivity reactions in Korea. In this study we have investigated the effect of heating on antigenicity and allergenicity change of soybeans by using immunoblotting and ELISA methods with serum of soybean allergic patients and polyclonal antibody against soybean proteins. Soybean proteins were extracted by one-hour heating in boiling waterbath and separated by SDS-PAGE. After heat treatment, no significant changes of soy protein patterns were observed in SDS-PAGE analysis. Furthermore, the heat treatment had no effect on the results in immunoblotting with polyclonal antibody as well as in ELISA with soybean allergic patients' serum. With these results it may be concluded that allergenicity and antigenicity of soybeans do not reduce by thermal treatment.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.235-236
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• 2014

인듐 주석 산화물 박막을 In/Sn (2, 5 wt.%) 합금 타겟을 사용하여 DC 마그네트론 반응성 스퍼터링법을 이용하여 증착하였다. 기판온도는 상온에서 증착하였으며, 증착 중 DC 파워는 70W부터 120W 까지 10W 단위로 증가시켜 증착하였다. 증착 된 박막을 대기중에서 후 열처리를 각 6, 12 시간 진행하여 전기적 특성을 평가하였으며 평가 장비는 Hall-effect measurements system을 사용하였다. ITO (Indium Tin Oxide) 박막의 비저항은 합금의 Sn 조성별로 다르게 나타났다. Sn 5wt.% 타겟을 이용한 경우에는 DC 파워 90W를 기준으로 더 낮은 파워에서는 열처리에 따라 비저항이 증가하였고, 더 높은 파워에서는 열처리를 한 경우 비저항이 더 낮게 나타났다. 이러한 결과가 나온 이유는, DC 파워가 높은 경우 스퍼터링 공정 중 발생하는 고 에너지 입자 충돌에 의해 산소가 re-sputtering되어 산소가 부족한 박막이 형성되기 때문인 것으로 판단된다. Sn 2 wt.% 타겟의 경우에는 큰 차이를 나타내지 않았으며, 이러한 원인은 Sn 함량이 적기 때문에 산소 공급으로 인해 결정성이 향상되더라도 활성화 Sn의 양이 적기 때문에 나타나는 현상으로 판단된다.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.421-428
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• 2016

In this work, pozzolanic activities of various waste materials were compared with those of well-known by-product pozzolanic materials. Undensified and densified silica fume, ASTM class F and class C fly ash, and metakaolin were chosen as well-known pozzolanic materials, and bentonite powder, ceramic powder obtained from wash basin, and waste glass wool, which can possibly possess pozzolanic property, were chosen for comparison. Drop in electrical conductivity at $40^{\circ}C$ saturated lime solution was measured for each materials. The amount of Ca(OH)2 decomposed from cement paste at $450{\sim}500^{\circ}C$ was also measured to evaluate pozzolanic activity. The 28 day compressive strength were used to observe the mechanical property enhanced by incorporation of various waste materials. According to the experimental results, using "difference between maximum conductivity value and conductivity value at 4 hour" was found to be a reasonable approach to determine pozzolanic activity of a material. Pozzolanic activity measured using electrical conductivity correlates very well with that measured using the amount of Ca(OH)2 remained in the cement paste. Relatively good agreement was also found with electrical conductivity and 28 day compressive strength. It was found that electrical conductivity measurement can be used to evaluate pozzolanic activity of unknown materials.

• KSBB Journal
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• v.10 no.3
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• pp.249-256
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• 1995

${\gamma}$-Glutamylcysteine production by the immobilized microbial system of recombinant Escherichia coli and yeast was investigated. ${\gamma}$-Glutamylcysteine was synthesized from L-glutamic acid and L-cysteine in the presence of ATP by the reaction catalyzed by ${\gamma}$-glutamylcysteine synthetase. An immobilized microbial cell system was developed for the efficient ${\gamma}$-glutamylcysteine production. Recombinant Escherichia coli and yeast were immobilized by alginate. Production of ${\gamma}$-glutamylcysteine was better with the recombinant Escherichia coli for both the synthesis of ${\gamma}$-glutamylcysteine and the ATP regeneration than the mixed system of recombinant Escherichia coli and yeast. The proper radio of recombinant Escherichia coli to yeast was experimentary observed to be 1:4 in the mixed system. Although the immobi1ized system had the slower reaction rate, its reaction stability was increased by 10%.

• The Journal of Dong Guk Oriental Medicine
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• v.6 no.2
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• pp.99-107
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• 1998

Cyclosporin A(CsA) is a selective immunosuppressive agent that has been credited with improved survival of solid organ allografts. Lymph node of BALB/C mouse administered CsA immunohistochemically observed to understand immunosuppressive effects of CsA on T lymphocytes, IL-2 receptors, and natural killer NK cells in lymph node. CsA orally administered daily for 10days at the dose 45mg/kg/day/. The lymph node were obtained at day 3, 7, and 14 after CsA administration and embedded with paraffin, and then stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly2(CD8), IL-2R(CD25), and NK-1.1(CD56). There were little changes of reactive degree and number of helper T lymphocytes, cytotoxic T lymphocytes, IL-2 receptors, and NK cells at day 3 after CsA administration, but they began to decrease at day 7. These decrease were greatest at day 14. The helper T lymphocytes. cytotoxic T lymphocytes, IL-2 receptors, and NK cells distributed in paracortex and medullary sinus. These results indicated that the secretion of IL-2 began to decrease at day 7 after CsA administration and subsequently to suppress T lymphocytes and NK cell as components of cell-mediated immunity.

• Journal of the Korean Ceramic Society
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• v.40 no.12
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• pp.1213-1219
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• 2003

Porous ceramics for microoganism carriers were prepared with amorphous alumina and pore formers by hydrothermal reaction, burn-out and wash-out method. Activated carbon with average size of 67,222, and 405 $\mu\textrm{m}$, organic polymer and inorganic salt were used as pore formers. Specimens were hydrothermally treated at 200$^{\circ}C$ for 24 h, heat-treated at 650$^{\circ}C$ for 5 h, and washed out at 80$^{\circ}C$ for 48 h. The formation of crystalline phase, porosity, pore size distribution and compressive strength were measured. The specimen with activated carbon was transformed to boehmite phase, but organic polymer and inorganic salt inhibited the aquohydroxoy complex gel and crystalline formation. The porous ceramics for microoganism carriers using activated carbon as a pore formers was successfully prepared, which is composed of ${\gamma}$-alumina phase with porosity of above 70 vol% and the compressive strength of 40 kgf/$\textrm{cm}^2$.

• KSBB Journal
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• v.17 no.2
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• pp.182-188
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• 2002

Enterococcus faecalis RKY1 cells were immobilized in an asymmetric hollow fiber bioreactor for application to the continuous production of succinic acid. The media was fed into shell-side of the module using a peristaltic pump, and the products were collected through lumen-side outlet. The number of hollow fibers within the module did not affect the bioreactor efficiency in the transverse operated hollow fiber bioreactor. The steady state at the outlet of hollow fiber bioreactor was reached after 24 hr cultivation at flow rate of 0.25 mL/mim, 12 hr at 0.5 L/min, and 9 hr at 1.0 mL/mm, respectively. The succinate and fumarate concentrations within the hollow fiber bioreactor, however, were as changeful as increasing the flow rate. During continuous operation with the flow rates between 0.5 and 2.0 mL, the productivity of succinate was 8.0-10.9 g/L $.$ hr at 30 g/L fumarate, 4.9-14.9 g/L hr at 50 g/L fumarate, and 7.2-17.1 g/L hr at 80 galL fumarate, respectively.

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.1
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• pp.33-41
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• 1998

Lymph node tissues of BALB/C mouse treated with DNCB were immunohistochemically observed to investigate the activation of cell mediated immunity in lymph node of murine with allergic contact dermatitis. The inguinal region of BALB/C mice were sensitized by one application of $25{\mu}l$ of 5% 2,4-dinitrochlorobenzene(DNCB) onto an abdominal skin and 2 weeks later, the mice were challenged with $4{\mu}l$ of 2.5% DNCB. The inguinal lymph node were obtained at hour 24, 48, and 72 after 2nd DNCB treatment and embedded with paraffin, and then stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly2(CD8), IL-2R(CD25). The distribution of helper T lymphocytes, cytotoxic T lymphocytes and IL-2 receptors began to increase at hour 24 after after 2nd DNCB treatment and these increase appeared in paracortical area and medullary sinius. These increase were greatest at hour 48. These results indicated that the IL-2 secretion began to increase by activation of helper T lymphocytes in lymph node of DNCB re-exposure area and subsequently to activate suppress T lymphocytes.

• Journal of Family Resource Management and Policy Review
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• v.25 no.4
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• pp.71-86
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• 2021

The purpose of this study is to identify the influencing factors of married men's household labor time by generation to understand the changes in male participation in household labor. To this end, married men were classified into Baby Boomers, Generation X, and Generation Y, and the factors of participation in household labor for each generation were analyzed by applying the hypothesis of participation in household labor. As for the data, the original data of the National Statistical Office's "2019 Time Use Survey" were used. Multinomial logistic analysis was conducted to analyze the factors affecting married men's household labor time. As a result of the analysis, household labor time for Baby Boomers can be explained by the hypothesis of economic efficiency, gender role attitude, and the demand/response capability, while household labor time for Generation X can be explained by economic efficiency hypothesis, gender role attitude hypothesis, time-availability hypothesis, and demand/response capability hypothesis. It was found that the household labor time for Generation Y can be explained by the time-availability hypothesis and demand/response capability hypothesis. The fact that each generation has different factors of participation in household labor suggests that the characteristics of each generation should be considered in establishing policies to support the work and family balance for men.