• 한국대기환경학회지
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• 제18권5호
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• pp.363-372
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• 2002

PM$_{10}$ aerosols were collected using low volume air sampler every month intervals from September 1992 to August 1991 in Seoul. These samples were analyzed for 20 trace elements (Al, As, Ba, Br, Ca, Cl, Co, Cr, Fe, K, Mn, Na, Ni, Pb, Sc, Se, Si, Ti, V and Zn) by INAA (instrumental neutron activation analysis), XRF (x-ray fuorescence spectrometer), and ICP (inductively coupled plasma). PM$_{10}$ mass concentrations higher than 70 $\mu$g/m$^3$ were 32% of 60 samples and had significantly higher concentrations in spring and winter than in summer and fall (p-value<0.001). The elements of As, Br, Cl, Ni, Pb, Se, V, and Zn are enriched by factors of 20 to 2,000 relative to their natural abundance in crustal soil. To further identify common sources of pollution-related trace elements, factor analysis was applied to the trace elements concentration data. Major sources that contribute to the atmospheric loading of these elements were found to include fossil fuel combustion, automobile and waste incineration (33.2%), metal processing industry (18.2%), and soil(29.8%).8%).

• 한국전기전자재료학회논문지
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• 제15권11호
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• pp.933-938
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• 2002

(Ba,Sr)TiO$_{4}$ (BST) thin films on Pt/Ti/SiO$_{2}$/Si substrates were deposited by a sol-gel method and the etch characteristics of BST thin films have been investigated as a function of gas mixing ratio. The maximum etch rate of the BST films was 440 $AA$/min under such conditions as: CF$_{4}$(CF$_{4}$＋Ar) of 0.2, RF-power of 700 W, DC-bias voltage of -200 V, pressure of 15 mTorr and substrate temperature of 30 $^{circ}C$. The selectivities of BST to Pt, SiO$_{2}$ and PR were 0.38, 0.25 and 0.09, respectively. In the XPS (X-ray photoelectron spectroscopy) analysis, Barium (Ba) and Strontium (Sr) component in BST thin films formed low volatile compounds such as BaFx, SrFx, which are forms by the chemical reaction with F atoms and is removed by Ar ion bombardment. Titanium (Ti) is removed by chemical reaction such as TiF with ease. The result of secondary ion mass spectrometry (SIMS) analysis confirmed the existence of the BaFx, SrFK, TiFx.

• 상하수도학회지
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• 제28권5호
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• pp.589-600
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• 2014

Tuberculation and slime accumulated in water mains play an important role in modifying water quality of drinking water. Therefore, in this study, it was investigated that what materials were accumulated, and what components were included in the tuberculation and slime of water mains. The Various tuberculation and slime sample were collected from the 12 water mains to analyze their physical and chemical properties and crystal structure. As a analysis method, VSS(Volatile suspended solid), SEM(scanning electron microscope), EDS(Energy Dispersive X-ray spectroscope), ICP(Inductively Coupled Plasma Mass Spectrometer) and XRD(X-Ray Diffractomete) were used. The results of analysis on the samples, the representative materials were verified such as iron corrosion products, the fine sand particles generated during backwash, fine particles of activated carbon, aluminum used in coagulation process, and manganese included in raw water.

• 한국대기환경학회지
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• 제19권6호
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• pp.701-717
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• 2003

The objective of this study was to extensively estimate the air quality trends of the study area by surveying con-centration trends in months or seasons, after analyzing the mass concentration of PM-10 samples and the inorganic lements, ion, and total carbon in PM-10. Also, the study introduced to apply the PMF (Positive Matrix Factoriza-tion) model that is useful when absence of the source profile. Thus the model was thought to be suitable in Korea that often has few information about pollution sources. After obtaining results from the PMF modeling, the existing sources at the study area were qualitatively identified The PM-10 particles collected on quartz fiber filters by a PM-10 high-vol air sampler for 3 years (Mar. 1999∼Dec.2001) in Kyung Hee University. The 25 chemical species (Al, Mn, Ti, V, Cr, Fe, Ni, Cu, Zn, As, Se, Cd, Ba, Ce, Pb, Si, N $a^{#}$, N $H_4$$^{+}$, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$, C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, TC) were analyzed by ICP-AES, IC, and EA after executing proper pre - treatments of each sample filter. The PMF model was intensively applied to estimate the quantitative contribution of air pollution sources based on the chemical information (128 samples and 25 chemical species). Through a case study of the PMF modeling for the PM-10 aerosols. the total of 11 factors were determined. The multiple linear regression analysis between the observed PM-10 mass concentration and the estimated G matrix had been performed following the FPEAK test. Finally the regression analysis provided source profiles (scaled F matrix). So, 11 sources were qualitatively identified, such as secondary aerosol related source, soil related source, waste incineration source, field burning source, fossil fuel combustion source, industry related source, motor vehicle source, oil/coal combustion source, non-ferrous metal source, and aged sea- salt source, respectively.ively.y.

• Journal of Radiation Protection and Research
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• 제41권4호
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• pp.359-367
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• 2016

Background: As new legislation has come into force implementing radiation safety management for the use of naturally occurring radioactive materials (NORM), it is necessary to establish a rapid and accurate measurement technique. Measurement of $^{238}U$ and $^{232}Th$ using conventional methods encounter the most significant difficulties for pretreatment (e.g., purification, speciation, and dilution/enrichment) or require time-consuming processes. Therefore, in this study, the applicability of ED-XRF as a non-destructive and rapid screening method was validated for raw materials and by-product samples. Materials and Methods: A series of experiments was conducted to test the applicability for rapid screening of XRF measurement to determine activity of $^{238}U$ and $^{232}Th$ based on certified reference materials (e.g., soil, rock, phosphorus rock, bauxite, zircon, and coal ash) and NORM samples commercially used in Korea. Statistical methods were used to compare the analytical results of ED-XRF to those of certified values of certified reference materials (CRM) and inductively coupled plasma mass spectrometry (ICP-MS). Results and Discussion: Results of the XRF measurement for $^{238}U$ and $^{232}Th$ showed under 20% relative error and standard deviation. The results of the U-test were statistically significant except for the case of U in coal fly ash samples. In addition, analytical results of $^{238}U$ and $^{232}Th$ in the raw material and by-product samples using XRF and the analytical results of those using ICP-MS ($R^2{\geq}0.95$) were consistent with each other. Thus, the analytical results rapidly derived using ED-XRF were fairly reliable. Conclusion: Based on the validation results, it can be concluded that the ED-XRF analysis may be applied to rapid screening of radioactivities ($^{238}U$ and $^{232}Th$) in NORM samples.

• 분석과학
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• 제22권3호
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• pp.201-209
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• 2009

국내에서 유통 중인 동물성 생약 38개 품목 총 325개 시료를 대상으로 ICP-MS와 수은자동분석기기를 이용하여 납, 카드뮴, 비소, 수은의 오염실태 조사를 수행하였다. 검출된 농도 범위는 납 $0.02{\mu}gkg^{-1}$ $(D.L){\sim}11.29mgkg^{-1}$, 카드뮴 $0.01{\mu}gkg^{-1}$ $(D.L){\sim}2.50 mgkg^{-1}$, 비소 $0.12{\mu}gkg^{-1}$ $(D.L){\sim}5.27mgkg^{-1}$이었으며, 수은의 경우 검출 범위를 초과한 한 개의 시료를 제외하면 $0.01{\sim}77.11mgkg^{-1}$으로 나타났다. 전체 동물성 생약 38품목 중 납, 카드뮴, 비소, 수은 모두가 잔류허용기준치 이하로 검출된 동물성 생약은 별갑과 오배자 2개 품목이었고, 22개 품목에서 납의 오염이 가장 큰 비중을 차지하였다. 수은의 경우 농도 범위가 비교적 넓게 나타난 녹각 등 16개 품목뿐만 아니라 전체 시료의 54.46%가 잔류허용기준치를 초과하였다. 따라서 납과 수은에 대한 지속적인 실태조사를 실시하고 오염원인 추적을 위한 연구가 수행되어야 할 필요가 있는 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제36권6호
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• pp.377-383
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• 2006

The purpose of the present study was to examine the pharmacokinetic characteristics of arsenic hexaoxide($As_4O_6$), a novel anticancer compound, after i.v. bolus and oral administration in rats. We developed an ICP-Mass based method to analyze arsenic hexaoxide levels in plasma, bile, urine, feces, and tissue and validated the method. Arsenic hexaoxide rapidly disappeared from the plasma by 10 min($\alpha$ phase) after i.v. administration, which was followed by the late disappearance in the $\beta$ phase. The mean plasma half-lives($t_{1/2}$) of arsenic hexaoxide at the a and $\beta$ phase when administered at a dose of 5 mg/kg were 1.57 and 29.8 min, respectively. The maximum plasma concentration($C_{max}$) was 230 ng/mL, after oral administration of arsenic hexaoxide at a dose of 50 mg/kg. The bioavailability, which was calculated from the dose-adjusted ratio, of the oral administered arsenic hexaoxide was 1.61%. Of the various tissues tested, arsenic hexaoxide was mainly distributed in the spleen, lung, liver and kidney after oral administration. Arsenic hexaoxide levels in the spleen or lung at 24 hr after oral administration were higher than those of maximum plasma concentration($C_{max}$). The cumulative amounts of arsenic hexaoxide found in the urine by 48 hr after the administration of 50 mg/kg were 5-fold higher than those in the bile. However, the cumulative amounts in the feces were 10-fold higher compared with those of urine, suggesting that arsenic hexaoxide is mostly excreted in the feces. In conclusion, our observations indicated that arsenic hexaoxide was poorly absorbed from the gastro-intestinal tract to the blood circulation and transferred to tissues such as the spleen and lung at 24 hr after oral administration. Moreover, the majority of arsenic hexaoxide appears to be excreted in the feces by 48 hr after oral administration.

• 에너지공학
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• 제7권1호
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• pp.146-156
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• 1998

석탄을 연소한 후 형성되는 석탄회는 미세한 분말상태로 입자의 형상은 다공성이며 단단한 구형입자로 이루어져 있다. 본 연구에서는 국내 발전소에서 생성된 9종의 석탄회의 물리적, 형태적 및 화학적 조성 분석을 통해 국내 석탄회 데이터 베이스화, 연소효율 개선, 석탄회 집진설비인 전기집진기의 성능향상과 석탄회의 재활용에 기여하고자 한다. 석탄회의 물리적 특성은 입도분포와 비중을 입자카운터와 한국공업규격(KS L-5110)에 따른 비중 측정계를 이용하였으며, 형태적 특성은 입자의 구형성 정도, 표면특성 그리고 색상변화 등을 전자현미경(SEM)과 광학현미경을 이용하였다. 그리고 화학적 특성을 파악하기 위해 유도결합 플라즈마방출 분광기(ICP)와 에너지스펙트럼 분석기(EDXA)를 이용하여 석탄회의 구성성분을 분석하였고 한국공업규격 KS L-5405에 따른 석탄회에 함유된 미연탄소분을 측정하였다. 삼천포 화력발전소 전기집진기에서 포집한 석탄회에 대한 질량평균입경은 각각 15~25 $\mu\textrm{m}$로 나타났다. 석탄회 입자의 형상은 석탄 입자가 보일러의 연소 영역에 노출되는 정도에 따라 구형성, 투명성 및 색변화가 다양하게 나타나는데 완전 연소에 가까울수록 무색의 구형입자가 형성되었다. 석탄회는 보일러 내의 연소 조건과 원탄의 성분에 따라 구형, 무정형, Cenosphere 그리고 Plerosphere와 같은 유형의 입자를 형성하며 입자간의 상호 작용에 의해 집괴, 응집 그리고 결정형의 입자군들을 형성한다. 석탄회는 산회광물질로 이루어져 있으며 주성분 SiO2, Fe2O3, Al2O3로 약 85% 이상을 차지하였으며 10% 정도는 미연탄소분으로 이루어져 있었다.

• 분석과학
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• 제21권4호
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• pp.316-325
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• 2008

연속흐름주입-수소화물생성-유도결합플라스마질량분석장치를 사용하여 바닷물시료중의 비소를 분석하였다. 두 종류의 바닷물표준시료인 CASS-4, NASS-5를 사용하여 측정값과 인증값을 비교함으로써 본 분석법의 정확성을 확인하였다. 분석결과 CASS-4의 경우 $1.17{\pm}0.07{\mu}g/L$ (인증값 $1.11{\pm}0.16{\mu}g/L$), NASS-5의 경우 $1.24{\pm}0.08{\mu}g/L$ (인증값 $1.27{\pm}0.12{\mu}g/L$)의 값을 얻었다. 이는 각각 독립적으로 5회 측정된 결과의 확장불확도로 표시된 결과이며 CASS-4의 경우 6.2%, NASS-5의 경우 6.8%이었으며 모두 인증값의 불확도 범위안에 있었다. 검량선의 기울기와 바탕값의 표준편차로부터 구한 $As^+$ (m/z=74.9216)의 검출한계는 0.01 ug/kg이었다. 검량선의 직선성은 매우 양호하였다. ($R^2=1$). DRC gas로 산소기체를 사용하여 $AsO^+$ (m/z=90.9165)로 검출하는 방법을 사용하여 결과를 비교하였으며 분석감도는 약 25배 정도 감소하였으나, 검량선의 직선성이 매우 잘 나타났으며, 분석결과도 $As^+$(m/z=74.9216)로 검출할 때와 동일한 결과를 얻을 수 있었다.

• 한국입자에어로졸학회지
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• 제4권2호
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• pp.51-67
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• 2008

In this study, we devoted to kinetic measurement of the catalytic oxidation of iron-containing flame soot particles and better understanding the role of catalytic particles on carbon oxidation in particular at low temperature, targeting on autothermal regeneration of diesel particulate filter by diesel exhaust gas. Carbon-based Fe-containing particles generated by spraying ferrocene-doped diesel fuel in an oxy-hydrogen flame are tested and compared with a commercial carbon black powder for thermogravimetric analysis (TGA), secondary ion mass spectrometry (SIMS), Fourier-transform infrared spectroscopy (FTIR), Induced coupled plasma-Atomic emission spectroscopy (ICP-AES), and High-resolution transmission electron microscopy (HR-TEM). As a result, we found that a small amount of the ferrocene addition led to significant reductions in a on-set temperature and an activation energy of the carbon oxidation as well. An oxygenated surface complex forming at the particle surface could be thought as active species that would be readily consumed in particular at low temperature.