Advanced H2O2 oxidation for diethyl phthalate degradation in treated effluents: effect of nitrate on oxidation and a pilot-scale AOP operation

Ko, K. B.,Park, C. G.,Moon, T. H.,Ahn, Y. H.,Lee, J. K.,Ahn, K. H.,Park, J. H.,Yeom, I. T. IWA Publishing 2008 Water Science & Technology Vol.58 No.5

<P>One of the objectives of this study was to delineate the effect of nitrate on diethyl phthalate (DEP) oxidation by conducting a bench-scale ultraviolet (UV)/H2O2 and O3/H2O2 operations as suggested in a previous study. We also aim to investigate DEP oxidation at various UV doses and H2O2 concentrations by performing a pilot-scale advanced oxidation processes (AOP) system, into which a portion of the effluent from a pilot-scale membrane bioreactor (MBR) plant was pumped. In the bench-scale AOP operation, the O3 oxidation alone as well as the UV irradiation without H2O2 addition could be among the desirable alternatives for the efficient removal of DEP dissolved in aqueous solutions at a low DEP concentration range of 85±15 μg/L. The adverse effect in the UV/H2O2 process was significantly greater than that in the UV oxidation alone, and its oxidation was almost halved by the nitrate. However, the nitrate clearly enhanced the DEP oxidation in the O3 oxidation and O3/H2O2 process. Especially, the addition of nitrate almost doubled the DEP oxidation efficiency in the O3/H2O2 process. The series of pilot-scale AOP operations confirmed that about 30-50% of DEP dissolved in the treated MBR effluent streams was, at least, oxidized by the O3 oxidation alone as well as the UV irradiation without H2O2 addition. The UV photolysis of H2O2 was most effective for DEP degradation with an H2O2 concentration of 40 mg/L at a UV dose of 500 mJ/cm2.</P>

Cowden's Disease - A Report on the First Case in Korea and Literature Review

Lee, H.-R Korean Academy of Medical Science 1997 Journal of Korean medical science Vol.12 No.6

초등교사의 감정노동, 사회적 지지와 삶의 질 간의 관계

경예빈,김보민,김수정,노지현,송지윤,염소희,이현아,허유림,홍소연,차지영,박수민 이화여자대학교 간호과학대학 2017 이화간호학회지 Vol.- No.51

Purpose: The purpose of this study was to examine the correlation of emotional labor, social support, and quality of life among elementary school teacher. Methods: A correlational descriptive design was used with convenience sampling between July and December, 2016. The survey was self reported questionnaire administered to 130 elementary school teachers in the urban area. Data was statistically analyzed using t-test and one way ANOVA. Results: The average score of participants' emotional labor is 2.80, social support 3.89 and quality of life 3.65 of the total of 5. Emotional labor was negatively correlated to social support (r=-.178, p<.05) and quality of life(r=-.438, p<.001). Social support was positively correlated to quality of life (r=.336, p<.001). Conclusion: This study has significance as a basic data to understand the relation of emotional labor, social support, quality of life among elementary school teachers. Also, nursing interventions suitable for elementary school teachers should be developed to decrease the level of emotional labor, strengthen the social support, and enhance their quality of life.

Cryomilling effect on the mechanical alloying behaviour of ferritic oxide dispersion strengthened powder with Y₂O₃

Kim, J.H.,Lee, J.H.,Min, J.Y.,Kim, S.W.,Park, C.H.,Yeom, J.T.,Byun, T.S. Elsevier Sequoia 2013 JOURNAL OF ALLOYS AND COMPOUNDS Vol.580 No.-

Cryogenic cooling effect on mechanical alloying of the mixture of Fe-14Cr-3W-0.1Ti and Y<SUB>2</SUB>O<SUB>3</SUB> powders was investigated. The powder mixtures were ball milled for 40h at room-temperature and -150<SUP>o</SUP>C. Cryomilling produced much finer particle/grain size than conventional room-temperature milling. XRD diffraction peak intensity was much lower under cryomilling conditions due to formation of nano-size grains and increased residual microstrain. Absorption amounts of interstitial elements were considerably higher under cryomilling conditions.

자장강화된 유도결합형 플라즈마를 이용한 산화막 식각에 대한 연구

안경준(K. J. An),김현수(H. S. Kim),우형철(R. Woo),유지범(J. B. Yoo),염근영(G. Y. Yeom) 한국진공학회(ASCT) 1998 Applied Science and Convergence Technology Vol.7 No.4

본 연구에서는 자장강화된 유도결합형 플라즈마를 사용하여 이 플라즈마의 특성을 조사하고 또한 산화막 식각에 미치는 영향에 대하여 조사하였다. 자장 강화를 위해 4쌍의 영구자석이 사용되었고, 산화막 식각을 위해 C₂F_6, CHF₃, C₄F_8 가스 및 이들 혼합가스가 사용되었으며 첨가가스로 H₂를 사용하였다. 자장강화된 유도결합형 플라즈마 특성 분석을 위해 Langmuir probe 와 optical emission spectrometer를 이용하였으며 산화막 식각 속도 및 photoresist에 대한 식각 선택비를 stylus profilometer를 이용하여 측정하였다. 이온 밀도에 있어서 자장 유무에 따른 큰 변화는 관찰되지 않았으나 이온전류밀도의 균일도는 자장을 가한 경우 웨이퍼가 놓이는 기판 부분에서 상당히 증가된 것을 알 수 있었다. 또한 자장이 가해진 경우, 자장을 가하지 않은 경우에 비해 플라즈마 전위가 감소된 반면 전자온도 및 라디칼 밀도는 크게 증가되는 것을 알 수 있었으며 산화막 식각시에도 높은 식각 속도와 식각 균일도를 보였다. 산화막 식각을 위해 수소가스를 사용한 가스조합중에서 C₄F_8/H₂가스조합이 가장 우수한 식각 속도및 photoresist에 대한 식각 선택비를 나타내었으며 공정변수를 최적화 함으로써 순수 C₄F_8에서 4이상의 선택비와 함께 8000 Å/min의 가장 높은 식각속도를 얻을 수 있었으며, 50%C₄F_8/50%H₂에서 4000 Å/min의 산화막 식각 속도와 함께 15이상의 식각 선택비를 얻을 수 있었다. In this study, the effects of multi-dipole type of magnets on the characteristics of the inductively coupled plasmas and SiO₂ etch properties were investigated. As the magnets, 4 pairs of permanent magnets were used and, to etch SiO₂, C₂F_6, CHF₃, C₄F_8, H₂, and their combinations were used. The characteristics of the magnetized inductively coupled plasmas were investigated using a Langmuir probe and an optical emission spectrometer, and SiO₂ etch rates and the etch selectivity over photoresist were measured using a stylus profilometer. The use of multi-dipole magnets increased the uniformity of the ion density over the substrate location even though no significant increase of ion density was observed with the magnets. The use of the magnets also increased the electron temperature and radical densities while reducing the plasma potential. When SiO₂ was etched using the fluorocarbon gases, the significant increase of SiO₂ etch rates and also the increase of etch uniformity over the substrate were obtained using the magnets. In case of gas combinations with hydrogen, C₄F_8/H₂showed the highest etch rates and etch selectivities over photoresist among the gas combinations with hydrogen used in the experiment. By optimizing process parameters at 1000 Watts of inductive power with the magnets, the highest SiO₂ etch rate of 8000 Å/min with the etch selectivity of 4 could be obtained for 100% C₄F_8 and the highest etch selectivity of over 15 with the SiO₂ etch rate of 4000 Å/min could be obtained for 50% C₄F_8/50% H₂.

Interspecies transmission of the canine influenza H3N2 virus to domestic cats in South Korea, 2010

Song, D. S.,An, D. J.,Moon, H. J.,Yeom, M. J.,Jeong, H. Y.,Jeong, W. S.,Park, S. J.,Kim, H. K.,Han, S. Y.,Oh, J. S.,Park, B. K.,Kim, J. K.,Poo, H.,Webster, R. G.,Jung, K.,Kang, B. K. Microbiology Society 2011 The Journal of general virology Vol.92 No.10

Fractionation of bovine x-Casein

Kang, S. H 韓國酪農學會 1996 韓國酪農學會誌 Vol.18 No.3

Molecular Composition and Fractionation of Colostral Casein with Advancing Lactation

Han, K. S 韓國酪農學會 1997 韓國酪農學會誌 Vol.19 No.1

Li_2 O-TiO_2 -P_2O_5계 다공질 결정화 유리의 항균특성

이용수,강원호,홍범수,염곤 단국대학교 신소재기술연구소 1998 신소재 Vol.8 No.-

인산염계에서 Ag^+ 이온을 함유하는 항균용 다공성 Glass-Ceramics를 제조하였다. 5Li_2O·36CaO·20TiO_2·26P_2O_5(mol%)조성의 유리를 모유리로서 선정하였으며, 모유리를 2단계 열처리하여 LiTi_2(PO_4)상과 β-Ca_3(PO_4)_2 결정상이 존재하는 Glass-Ceramics를 제조하였다. 1N-HCl 수용액으로 β-Ca_3(PO_4)_2결정상만을 선택적으로 용출시켰으며, LiTi_2(PO_4)_3결정상만이 존재하는 다공성 글래스 세라믹스를 제조하였다. 또한 이것을 0.1M AgNO_3 수용액에 담지시켜 Ag^+를 Li^+와 이온교환하였다. 그리고 이온교환된 시편을 살균특성평가를 통해 그 항균특성 및 살균효과를 관찰하였다. The anti-bacterial materials porous glass-ceramics containing Ag^+ was prepared by glass melting method in phosphate system. The final composition of the base glass was 5Li_2O·36CaO·20TiO_2·26P_2O_5(mol%) and the Glass Ceramics composed of LiTi_2(PO_4)_3 and β-Ca_3(PO_4)_2 was produced by 2-step heat treatment. Subsequently β-Ca_3(PO_4)_2 crystal was leached out selectively in 1N-HCl solution, leaving porous glass-ceramics with only Liti_2(PO_4)_3 crystal. Also, Ag^+ ion exchange with Li^+ was carried out in 0.1 M AgNo_3 solution. Then anti-bacterial effects and characterizations of the porous glass- ceramics were investigated.

Porous Glass Ceramics in the Ag_2O-Li_2O-CaO-TiO_2-P_2O_5

이용수,강원호,홍범수,염곤 단국대학교 신소재기술연구소 2000 신소재 Vol.9 No.-

인삼염계 xAg_2Oㆍ(5-x)Li_2Oㆍ36CaOㆍ20TiO_2ㆍ26P_2O_5(mole ratio) 조성의 유리를 모유리로서 선정하여, 모유리를 2단계 열처리 함으로써 LiTi_2(PO_4)_3상과 AgTi_2(PO_4)_3 및 β-Ca_3(PO_4) 결정상만을 선택적으로 용출하였으며 LiTi_2(PO_4)_3 상과 AgTi_2(PO_4)_3 결정상 만이 존재하는 다공성 Glass Ceramics를 제조하였다. 또한 서로 다른 Ag mole%를 갖는 여러 시료들에 대해서 S. aureus균과 S.typhi에 대한 항균성을 관찰하였다. The anti-bacterial materials of porous glass-ceramics containing Ag_2O was prepared by glass melting method in phosphate system. The composition of the base glass was xAg_2Oㆍ(5-x)Li_2Oㆍ36CaOㆍ20TiO_2ㆍ26P_2O_5(mole %) and the Glass Ceramics composed of poly crystalline LiTi_2(PO_4)_3, AgTi_2(PO_4)_3 and β-Ca_3(PO_4) was produced by heat treatment. Subsequently β-Ca_3(PO_4) crystal was leached out in 1N-HC1 solution selectively, leaving porous glass-ceramics with LiTi_2(PO_4)_3 and AgTi_2(PO_4)_3 crystal. Then anti-bacterial effects and characterizations of the porous glass-ceramics were investigated.