• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 춘계 학술대회
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• pp.278-283
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• 2005

원자력 발전소에서 발생한 시멘트 또는 파라핀 고화체 중의 핵종분석을 하기 위해서는 시료의 용액화가 필요하다. 이를 위하여 산 침출법과 극초단파 산분해법을 이용하여 SRM(standard reference material)을 용액화한 다음 AAS와 ICP-AES를 사용하여 용액 속의 원소들을 분석 비교하였다. 완전 용액화가 가능한 극초단파 산분해법으로 처리한 결과와 일치하는 산 침출조건을 제안하여 많은 양의 시료를 한 번에 처리할 수 있는 산 침출법으로 방사성 고화체 시료 중의 비휘발성핵종분석을 위한 고화체 용액화 방법을 확립하였다. 방사성 고화체의 산 침출시마다 Re을 첨가하여 시료 전처리 단계에서의 회수율은 $80\%$ 이상으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1433-1436
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• 2003

A new method for the simultaneous determination of heavy metal ions in cigarette material by microwave digestion and reversed-phase high-performance liquid chromatography (RP-HPLC) has been developed. The cigarette material was digested by microwave digestion. Lead, cadmium, mercury, nickel and tin ions in the digested samples were pre-column derivatized with tetra-(2-chlorophenyl)-porphyrin ($T_2$-CPP) to form color chelates, which were then enriched by solid phase extraction with a $C_{18}$ cartridge. The chelates were separated on a Waters Xterra$^{TM}RP_{18}$ column by gradient elution with methanol (containing 0.05 mol/L pyrrolidine-aceticacid buffer salt, pH = 10.0) and acetone (containin0.05 mol/L pyrrolidine-acetic acid buffer salt, pH = 10.0)as mobile phase at a flow rate of 0.5mL/min and analyzed with a photodiode array detector from 350-600 nm. The detection limits of lead, cadmium, mercury, nickel and tin were 4,3,3,8 and 5 ng/L, respectively, in the original samples. This method was afforded good results.

• 분석과학
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• 제14권2호
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• pp.173-179
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• 2001

K 수계 6개 지점의 퇴적물에 대해 Fe, Cu, Cr, Zn, Cd를 측정분석하였으며 분석방법들을 비교 분석하였다. 마이크로웨이브에 의한 전처리 방법이 미국의 TCLT(toxicity characteristic leaching procedure)나 폐기물공정시험방법보다 Fe, Cu, Cr, Zn, Cd 모두 높은 값을 나타내었다. 마이크로웨이브, TCLP, 폐기물 공정시험방법에 의한 중금속 분석결과 각각 38.1-48.0 mgFe/kg, 10.2-15.9 mgFe/kg, 3.5-12.6 mgFe/kg, 37.0-50.1 mgCu/kg, 0.06-0.24 mgCu/kg, 0.01-0.03 mgCu/kg 및 137.2-152.0 mgZn/kg, 0.67-0.82 mgZn/kg, 0.3-0.5 mgZn/kg으로 나타났다. 이상의 결과로부터 퇴적물 중에 오염도를 정확히 평가하기 위해서는 효율적이고 새로운 시험방법 개발 연구에 관심을 두어야 한다.

• 한국연초학회지
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• 제30권1호
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• pp.25-32
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• 2008

In this study, we compared three different pretreatment methods, such as block digestion, microwave digestion and solvent injection, coupled with Octopole Reaction System(ORS)-ICP-MS was used for the quantification of heavy metals in mainstream smoke of 2R4F reference cigarette, and then evaluated those efficiencies in the recovery, repeatability and reproducibility. In all methods, volatile heavy metals, As, showed the highest CV value, and Cd showed the lowest one. However, the solvent injection method showed the most stable recovery rate and CV value of 2.36 %. This method showed also advantages in time-consuming and compatibility with ICP-MS system. This results demonstrate that solvent injection method can be recommended as a superior pretreatment procedure to be able to reduce contaminants and spectral interference as well as loss of the elements interested.

• 한국식품위생안전성학회지
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• 제28권1호
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• pp.45-49
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• 2013

본 연구에서는 유화제를 사용하지 않고 초단파 산분해법을 이용해 우리나라에서생산된 참기름의 중금속을 측정하고자 하였다. ICP-MS를 통해 12개의 참기름 시료에 오염된 카드뮴, 납, 비소의 3종 중금속을 분석하였다. 분석법의 검증 결과 카드뮴, 납, 비소 모두 직선성($r^2$)이 0.99 이상이며 RSD는 4% 이하였다. 또한, 분석법의 정확성 및 효율성 측정을 위해 중금속 $10{\mu}g/g$과 $100{\mu}g/g$을 첨가한 시료를 분석한 결과, 회수율이 카드뮴 98.5-101.6%, 납 100.3-101.3%, 비소 102.1-111.2%로 우수하게 나타났다. 본 분석법을 이용하여 분석한 참기름 시료의 중금속 함량은 카드뮴 불검출${\sim}0.109{\mu}g/g$, 납 $0.014{\sim}0.200{\mu}g/g$, 비소 $0.014{\sim}0.125{\mu}g/g$이었다. 따라서, 중금속 오염지역에서 생산된 참깨 및 이를 이용한 가공품의 경우 섭취에 주의할 필요가 있다.

• Environmental Engineering Research
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• 제14권1호
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• pp.48-52
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• 2009

Solubilization of sewage sludge creates favorable conditions for anaerobic microorganisms to produce biogas. In this paper, we quantify the effect of heating pretreatment on the degree of solubilization of sewage sludge. The pretreatment process was carried out using a lab-scale industrial microwave unit (2450 MHz frequency). Response surface analysis was applied to determine the combination of temperature-increase rate (ramp rate) (2.9 to 17.1 ${^{\circ}C}$/min) and terminal temperature (52 to 108${^{\circ}C}$). Both ramp rate and temperature significantly affected the solubilization degree of sludge. Within the design boundaries, the conditions predicted to maximize the solubilization degree of 15.8% were determined to be 2.9 ${^{\circ}C}$/min and 104${^{\circ}C}$.

• Asian-Australasian Journal of Animal Sciences
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• 제23권3호
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• pp.347-354
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• 2010

This study aimed to evaluate effects of 800 W microwave irradiation for 2, 4 and 6 min on chemical composition, antinutritional factors, ruminal dry matter (DM) and crude protein (CP) degradability, and in vitro CP digestibility of canola seed (CS). Nylon bags of untreated or irradiated CS were suspended in the rumen of three bulls from 0 to 48 h. Protein subfractions of untreated and microwave irradiated CS before and after incubation in the rumen were monitored by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Microwave irradiation had no effect on chemical composition of CS (p>0.05). There was a linear decrease (p<0.001) in the phytic acid and glucosinolate contents of CS as irradiation time increased. Microwave irradiation for 2, 4 and 6 min decreased the phytic acid content of CS by 8.2, 27.6 and 48.6%, respectively. The total glucosinolate contents of CS microwave irradiated for 2, 4 and 6 min decreased by 41.5, 54.7 and 59.0% respectively, compared to untreated samples. The washout fractions of DM and CP and degradation rate of the b fraction of CP decreased linearly (p<0.001) as irradiation time increased. Microwave irradiation for 2, 4 and 6 min decreased effective degradability (ED) of CP at a ruminal outflow rate of 0.05 $h^{-1}$ by 4.7, 12.3 and 21.0%, respectively. Microwave irradiation increased linearly (p<0.001) in vitro CP digestibility of ruminally undegraded CS collected after 16 h incubation. Electrophoresis results showed that napin subunits of untreated CS disappeared completely within the zero incubation period, whereas cruciferin subunits were degraded in the middle of the incubation period (16 h incubation period). In 4 and 6 min microwave irradiated CS, napin subunits were degraded after 4 and 16 h incubation periods, respectively, and cruciferin subunits were not degraded untile 24 h of incubation. In conclusion, it seems that microwave irradiation not only protected CP of CS from ruminal degradation, but also increased in vitro digestibility of CP. Moreover, microwave irradiation was effective in reducing glucosinolate and phytic acid contents of CS.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권2호
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• pp.40-46
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• 2010

In this study, microwave irradiation, which is reflected by metals, was used to reduce the amount of sewage sludge, and the results were used to verify solubilization efficiency and determine optimum operation conditions. Biogas production and methane content of the gas under optimized conditions were measured with the biochemical methane potential (BMP) test. The sludge was taken from a thickened sludge tank at J sewage treatment plant (JSTP) in Seoul, Korea. For the experiments, 50 mL of sludge was filled in vessels and the vessels were irradiated with the power of 500, 600, 700, and 800W for 2~5 min. In addition, Fe powder was added by 0.01, 0.05, and 0.1 g to compare the efficiency with and without Fe powder. The results confirmed that solubilization efficiency was higher in the presence of Fe powder. The optimum conditions of 0.01 g addition of Fe powder with 800W irradiation for 5 min, yielded nearly 22.95% higher solubilization efficiency than without Fe powder. The BMP tests were carried out using sludge obtained from the experiments carried out under the optimum conditions. As a result, sludge subjected by 800W with 0.01 g of Fe powder for 5 min displayed the highest level of gas production and methane content. Through this study, it could be confirmed that solubilization efficiency increased by addition of Fe powder.

• 펄프종이기술
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• 제42권5호
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• pp.67-73
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• 2010

Paper packaging materials are essential in protection and transportation of commercial or industrial products. Raw materials for packaging paper production are mainly obtained from various grades of waste paper. For this reason, the recycled fibers from waste paper would probably have possibility of containing heavy metals. This study was focused on the development of optimum pre-treatment method for the quantitative analysis of mercury. The optimum pre-treatment for open digestion system were obtained at the treatment conditions of acid combination with $HNO_3/HCl/H_2O_2$ or $HNO_3/H_2SO_4$ at $80^{\circ}C$. The optimum pre-treatment conditions in closed digestion system were determinated by the acid combination with $HNO_3/HCl/H_2O_2/HF$ in microwave at 320 W for 20 min. The recovery rate in open digestion system was 85~94% and in closed digestion system was indicated as about 100%. Therefore, the closed system is superior than the open system in pre-treatment method for the quantitative analysis of mercury, and the detected mercury contents in the sample of KOCC, AOCC and kraft sack paper were measured below 1 ppm.

• 분석과학
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• 제11권4호
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• pp.281-291
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• 1998

혈액과 소변중의 미량 Cu, Sn 및 Bi를 유도결합 플라스마 질량분석법으로 동시 분석하였다. 혈액시료 1 mL를 closed-vessel digestion system에 넣고 질산과 과산화수소수를 가한 후 microwave oven에서 8분 동안 전처리하였다. Amberlite IRC-718 수지를 정지상으로 사용한, 고체-액체추출법으로 Na, S, P 및 polyatomic species에 의한 매트릭스 방해를 제거하였다. 위 방법에 대한 검출한계를 구한 결과 Cu는 0.000375 ng/mL, Sn 은 0.000297 ng/mL, Bi는 0.000174 ng/mL 이었다. NIST SRM 955a 혈액시료에 표준용액을 첨가하여 구한 회수율은 Cu의 경우 99.1%, Sn은 102.5%, Bi는 98.4%이었다. 아울러 본 연구에서 조사한 최적기기 및 분석조건에서 실제 혈액과 소변시료의 분석을 시도하였다.