• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.176-177
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• 2013

Surface plasmon polaritons (SPPs) have attracted the attention of scientists and engineers involved in a wide area of research, microscopy, diagnostics and sensing. SPPs are waves that propagate along the surface of a conductor, usually metals. These are essentially light waves that are trapped on the surface because of their interaction with the free electrons of conductor. In this interaction, the free electrons respond collectively by oscillating in resonance with the light wave. The resonant interaction between the surface charge oscillation and the electromagnetic field of the light constitutes the SPPs and gives rise to its unique properties. In this papers, we studied theoretical and experimental extraordinary transmittance (T) and reflectance (R) of 2 dimensional metal hole array (2D-MHA) on GaAs in consideration of the diffraction orders. The 2d-MHAs was fabricated using ultra-violet photolithography, electron-beam evaporation and standard lift-off process with pitches ranging from 1.8 to $3.2{\mu}m$ and diameter of half of pitch, and was deposited 5-nm thick layer of titanium (Ti) as an adhesion layer and 50-nm thick layer of gold (Au) on the semiinsulating GaAs substrate. We employed both the commercial software (CST Microwave Studio: Computer Simulation Technology GmbH, Darmstadt, Germany) based on a finite integration technique (FIT) and a rigorous coupled wave analysis (RCWA) to calculate transmittance and reflectance. The transmittance was measured at a normal incident, and the reflectance was measured at variable incident angle of range between $30^{\circ}{\sim}80^{\circ}$ with a Nicolet Fourier transmission infrared (FTIR) spectrometer with a KBr beam splitter and a MCT detector. For MHAs of pitch (P), the peaks ${\lambda}$ max in the normal incidence transmittance spectra can be indentified approximately from SP dispersion relation, that is frequency-dependent SP wave vector (ksp). Shown in Fig. 1 is the transmission of P=2.2 um sample at normal incidence. We attribute the observation to be a result of FTIR system may be able to collect the transmitted light with higher diffraction order than 0th order. This is confirmed by calculations: for the MHAs, diffraction efficiency in (0, 0) diffracted orders is lower than in the (${\pm}x$, ${\pm}y$) diffracted orders. To further investigate the result, we calculated the angular dependent transmission of P=2.2 um sample (Fig. 2). The incident angle varies from 30o to 70o with a 10o increment. We also found the splitting character on reflectance measurement. The splitting effect is considered a results of SPPs assisted diffraction process by oblique incidence.

• 보존과학회지
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• 제36권2호
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• pp.82-92
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• 2020

현대 미술작품은 재료와 제작기법, 종류가 매우 다양하게 사용되고 있으며 특히 조각작품 중 많은 비율을 차지하는 금속의 경우 형태가 다양하고 여러 재질과 혼합된 작품이 다수 존재한다. 이러한 구조적, 재료적 특성은 보존처리 시 기존의 처리 방법을 적용하기 어려운 경우가 많아 보다 다양한 처리 재료 및 방법이 요구된다. 본 연구에서는 금속 작품의 효과적인 보존처리를 위해 방청제(Rust inhibitor, 防錆劑)를 작품에 직접적으로 도포하는 방법이 아닌 기화성 방청제를 적용하였으며, 기화성 방청제 및 이를 함유한 방청필름의 방청효과를 평가하였다. 금속 시편을 대상으로 기화성 방청제를 적용한 방청처리 결과, 시편의 색도 변화는 미미하였으며, 부식 속도는 방청 미처리 시편과 비교하였을 때 절반 정도 감소하는 것을 확인하였다. 방청필름 적용 실험 결과, 방청필름 사용 시 미처리 및 폴리에틸렌 필름을 사용한 시편보다 부식화합물의 발생이 감소하였다. 접촉각 및 표면에너지, 표면전기저항 측정을 통해 표면의 물성을 측정하였으며 방청피막이 형성됨을 확인하였다. 또한 기화성 방청제 및 방청필름을 실제 조각작품에 적용하여 방청효과를 확인하였다.

• Journal of the korean society of oceanography
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• 제33권4호
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• pp.168-177
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• 1998

Five and a half months after the Keumdong oil spill accident on the 21$^{st}$ of September 1993, 34 seawater samples and 94 sediment samples were collected from Kwangyang Bay and Namhaedo area to assess its environmental impacts. Hydrocarbon concentration in the seawater ranged from 0.8 to 9.2 ${\mu}$g/1 with an average of 3.3 ${\mu}$g/1. This average value was nearly the same as the value(3.7 ${\mu}$g/1) before the oil spill accident. This suggests that by the early March of 1994 majority of the coastal water in the study area restored to its background hydrocarbon concentration before the oil spill accident. Nutrients, heavy metals and other general environmental parameters of the seawater did not show any aggravated seawater quality compared with the previous records. From the regression analysis of time-course observation of hydrocarbon in the seawater, except the sediment environment, the effect of oil spill on the water column was estimated to last at least 4 months in the study area after the oil spill accident. In the shoreline sediments, oil deposits were, however, still found at the high water marks at several stations, and very high values were found in the west of Namhaedo, ranging from 3.7 to 40.1 mg/g of wet sediment. Gas chromatography of these samples showed a very distinct Bunker C chromatogram identical to the Keumdong oil spill. Hydrocarbons in the subtidal bottom sediments in the study area and the reference stations (YB and CB) ranged from 0.45 to 18.08 ${\mu}$g/g of wet sediment with an average of 3.09 ${\mu}$g/g. West of Namhaedo (Stations Bl2-B33) generally showed much higher values than inner Kwangyang Bay and in Chinju Bay. Chinju Bay generally showed the lowest value among the study area. Subtidal bottom sediments in inner Kwangyang Bay and Chinju Bay seemed to be less affected than west of Namhaedo. Heavy metal concentrations in the sediment were relatively higher in the Kwangyang Bay than in the Chinju Bay. However, metal concentrations in the study area were in general comparable to the reference areas.

• 한국수산과학회지
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• 제45권4호
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• pp.317-327
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• 2012

The changes in the proximate compositions, lipid classes, and fatty acids of muscle and dripped lipids, and the amino acid compositions and mineral content were studied in Spanish mackerel Scomberomorus niphonius muscle cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw sample (65.7%) and decreased with cooking, decreasing the most with frying pan method (54.5%). Conversely, the protein, lipid and ash contents increased significantly with cooking (P<0.05). The dripped lipid content from the cooked muscles was the highest with the frying pan sample (0.81%) and was approximately half this level in the oven (0.46%) and microwave oven (0.34%) samples. The percentage of non-polar lipid (NL) in the total lipid content exceeded 95% for the muscle lipids (13.9-17.6 g/100 g sample) and 99% for the dripped lipids (0.34-0.81 g/100 g sample). The prominent fatty acids were 18:1n-9, 16:0, 22:6n-3, 16:1n-7, and 20:5n-3 in the muscle and dripped lipids. The frying pan muscle lipid contained high levels of saturates and monoenes such as 16:0, 18:0, and 18:1n-9, and low levels of polyenes compared with other muscle lipids. The fatty acid compositions of the dripped lipids were similar with all three cooking methods. The prominent total amino acids in Spanish mackerel muscle were glutamic acid, aspartic acid, lysine, leucine, and arginine, and their proportions were similar (45.49-45.82%) in all samples. The potassium and phosphorous contents increased significantly with cooking (P<0.05), and while no heavy metals were detected in any sample. These results indicate that the change in nutritional components, especially the lipid content, was lower with the microwave oven and oven methods compared with the frying pan method.

• 유기물자원화
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• 제11권2호
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• pp.117-124
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• 2003

음식물쓰레기 이용 퇴비화의 운전 및 염분저감을 위한 적정조건 검토을 위한 연구를 수행하여 이하의 결과를 얻었다. 음식쓰레기와 톱밥을 7:3, 6:4, 5:5, 4:6, 3:7 비율로 혼합하여 실험한 결과 6:4에서 가장 안정화된 퇴비가 생산될 수 있었다. 한편 음식물쓰레기 : 톱밥의 혼합비가 7:3 및 음식물쓰레기 : 왕겨의 혼합비가 6.5 : 3.5 와 6:4의 경우는 초기 C/N비 자체가 낮게 나타나 적정 퇴비화를 이룩하기 어려웠다. Agent로 톱밥을 혼합한 경우와 왕겨를 혼합한 경우 모두 pH가 급격히 상승하다가 안정화되어 7.5~8.5를 유지하였다. 수분함량은 왕겨를 사용한 경우가 톱밥을 사용한 경우보다 수분감량율이 높게 나타나 톱밥보다 공극율 및 통기성이 원활함을 알 수 있었다. 따라서 톱밥대체제로 이용가능 했다. 탄소화합물 함량은 톱밥의 경우 음식물쓰레기의 혼합 비율이 낮을수록, 왕겨의 경우 음식물쓰레기의 혼합 비율이 높을수록 높았다. 유해성분(납외7종)은 비료기준치 이하를 나타내 안전한 것으로 판별되었다. 염분의 경우 0.43-0.46%을 나타내어 비료기준치(1%)의 1/2로 저감되었다. 이상의 결과를 종합해 보면 음식물쓰레기 퇴비화에 있어 음식물쓰레기와 Agent의 혼합비가 6:4 일 때, Agent로는 왕겨보다 톱밥을 혼합할 때 효율적인 것으로 나타났다.

• 한국자기학회지
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• 제15권1호
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• pp.1-6
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• 2005

높은 큐리온도를 가질 수 것으로 예측된 전이금속이 도핑된 ZnO의 전자구조와 자성을 제일원리계산방법을 이용하여 연구하였다. 본 연구에서 전이금속은 Ti, Cr, Mn, Fe, Co, Ni, Ru, Pd, Ag 이고 도핑 수준은 25%로 두고 계산하였다. 자성연구에서 가장 적합한 방법으로 알려져 있는 Full-potential Linearized Augmented Plane Wave(FLAPW)방법을 사용하였으며 교환-상관 전위는 general gradient approximation(GGA)를 사용하였다. 도핑된 전이금속 (Ti, Cr, Mn, Fe, Co, Ni, Ru, Pd, Ag)은 각각 0.83, 3.03, 4.03, 3.48, 2.47, 1.56, 0.43, 0.75, 0.01 ${\mu}_B$의 자기모멘트를 가지며, 전이금속에 이웃한 O 원자도 가안 띠혼성으로 측정 가능한 자기모멘트를 가질 수도 있는 것으로 계산되었다. 3d 전이금속이 도핑된 ZnO는 (CoZnO를 제외하고) 절반금속 특성을 가지는 것으로 계산되었다. 또한 4d 전이금속이 도핑된 경우는 강자성 상태가 상자성 상태에 비해 에너지차이가 크지 않을 뿐 아니라 페르미 준위에 다수 스핀과 소수 스핀 상태 모두가 페르미 준위에 위치해 있어 스핀분극 정도가 낮았다.

• 자원환경지질
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• 제24권3호
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• pp.245-260
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• 1991

Surficial dispersion patterns of heavy metals and toxic elements (U, Mo, Cu, Zn, Fe, Mn, Co, Cr, V, Ni, Pb, and Cd) were investigated in the Dukpyungri, Goesan area covered with low grade uranium-bearing black shales. Maximum abundance of U in the black shale was 455ppm. Radioactivity was counted at a maximum of 7cps in black shales, and was less than 0.5cps in shales, slates, and oil shales of the control areas. Enrichment of Mo, V, Cu, Zn, Cd, and Pb in black shales is particularly characteristic compared with shales, slates, and oil shales of the control areas, whereas contents of Mn, Cr, Co, and Th in all rock samples tend to be almost similar. Residual top soils (0~15cm depth) over black shales show high contents of Mo, Cu, Zn, Ni, Cd, and V in comparison with the control areas. Contents of trace elements in subsoils (15~30cm depth) were higher about one and half times than those in topsoils. Average contents of Mo, Cu, Pb, Zn, Cd and V in garden soil and playground soil of an elementary school in Dukpyungri, Goesan area, were high about two to fifteen times compared with the control areas. Contents of trace elements in stream sediments were higher from two to eight times than those in residual soils. Sodium, AI, K, V, Cr, and Fe were more enriched in the roots of pine than in the twigs of pine. Contents of Li, AI, V, Ni, Cd, Fe, and Co were higher in the roots of azalea than in the twigs of azalea. Enrichment of P, Ca, and Mg was remarkable in the twigs of both pine and azalea. Biological absorption coefficients for essential elements (Zn, P, Mn, Ca and K)tend to be high, whereas those for the non-essential elements.(Ba, Ti, V, and Mo) and toxic elements(Cr, Co, Pb and Ni) be low. Less mobile elements (Pd, Cd, and Co) tend to show anomalies with higher contrast than more mobile elements(Mo, V, Zn, Cu and Ni) in the area covered with black shales.

• 대한환경공학회지
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• 제30권6호
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• pp.659-665
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• 2008

본 연구는 서울특별시 소재 S 물재생센터의 하수슬러지 소각로에서 발생하는 비산재를 이용한 제올라이트 합성에 관한 것이다. 이를 위해 출발물질로서 소각비산재의 특성, 제올라이트 합성을 위한 수열반응조건, 합성된 제올라이트의 적용성을 조사하였다. 하수슬러지 소각 비산재에는 중량으로 각각 42.8%와 21.2%로 많은 양의 SiO$_2$와 Al$_2$O$_3$를 함유하고 있어, 제올라이트 합성의 출발물질로 이용이 가능하였다. 소각 비산재의 중금속 유해성 파악을 위해 용출시험과 함유량 시험을 실시하였는데, 용출시험 결과는 폐기물관리법에서 규제하는 용출기준에 비해 매우 적은 양이 검출되었으나, 함유량 시험에서는 비료관리법 상의 보통 비료 중 유기질 비료 및 부산물 비료의 중금속 위해성 기준을 초과하였다. 수열반응 결과, 주로 생성된 제올라이트는 analcime과 zeolite P1이었다. Analcime은 teflon 반응용기에서 생성되었고, 최적의 반응조건은 알칼리(NaOH)용액의 농도 1 N, 합성온도 135$^{\circ}C$, 합성시간 16시간이었다. 한편, Zeolite P1은 붕규산 유리질 반응용기에서 합성되었고, 알칼리(NaOH)용액 농도 5 N, 합성온도 130$^{\circ}C$, 합성시간 16시간에서 가장 많은 양이 합성되었다. 수열반응 후의 유해 중금속 함유량은 합성전과 비교하여 analcime 생성물에서는 비슷한 수준으로, zeolite P1 생성물에서는 약 절반 정도 감소하였다. 합성된 제올라이트의 성능은 암모늄 이온의 교환정도로서 파악하였는데, 소각 비산재에서 0$\sim$1.0 mg NH$_4{^+}$/g, analcime합성물 3.0$\sim$7.4 mg NH$_4{^+}$/g, 그리고 zeolite P1합성물에서 14.6$\sim$17.8 mg NH$_4{^+}$/g이었다. 천연 제올라이트인 clinoptilolite와 phillipsite의 암모니아 제거능력이 15$\sim$35 mg NH$_4{^+}$/g 정도인데, 본 연구에서는 zeolite P1합성물이 이 범위를 충족하였다. 이러한 관점에서 하수슬러지 소각 비산재를 이용한 제올라이트 합성은 폐기물 재활용의 좋은 대안이 될 수 있을 것으로 판단된다.

• Journal of Preventive Medicine and Public Health
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• 제42권2호
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• pp.89-95
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• 2009

Objectives : To assess the protective effects of wearing protective devices among the residents and volunteers who participated in the cleanup of the Hebei Spirit oil spill. Methods : A total of 288 residents and 724 volunteers were surveyed about symptoms, whether they were wearing protective devices and potential confounding variables. The questionnaires were administered from the second to the sixth week following the accident. Spot urine samples were collected and analyzed for metabolites of 4 volatile organic compounds(VOCs), 2 polycyclic aromatic hydrocarbons(PAHs), and 6 heavy metals. The association between the wearing of protective devices and various symptoms was assessed using a multiple logistic regression adjusted for confounding variables. A multiple generalized linear regression model adjusted for the covariates was used to test for a difference in least-square mean concentration of urinary biomarkers between residents who wore protective devices and those who did not. Results : Thirty nine to 98% of the residents and 62-98% of volunteers wore protective devices. Levels of fatigue and fever were higher among residents not wearing masks than among those who did wear masks(odds ratio 4.5; 95% confidence interval 1.23-19.86). Urinary mercury levels were found to be significantly higher among residents not wearing work clothes or boots(p<0.05). Conclusions : Because the survey was not performed during the initial high-exposure period, no significant difference was found in metabolite levels between people who wore protective devices and those who did not, except for mercury, whose biological half-life is more than 6 weeks.