• 전기학회논문지
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• 제56권2호
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• pp.349-354
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• 2007

In this work, we investigated etching characteristics of $HfO_2$ thin film and Si using inductive coupled plasma(ICP) system. The ion energy distribution functions in an ICP system was analyzed by quadrupole mass spectrometer(QMS) with an electrostatic ion energy analyzer. The maximum etch rate of $HfO_2$ thin film is 85.5 nm/min at a $BCl_3/(BCl_3+Ar)$ of 20 % and decreased with further addition of $BCl_3$ gas. From the QMS measurements, the most dominant positive ion energy distributions(IEDS) showed a maximum at 20 % of $BCl_3$. These tendency was very similar to the etch characteristics. This result agreed with the universal energy dependency of ion enhanced chemical etching yields. And the maximum selectivity of $HfO_2$ over Si is 3.05 at a $O_2$ addition of 2 sccm into the $BCl_3/(BCl_3+Ar)$ of 20 % plasma.

• 보존과학회지
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• 제30권1호
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• pp.33-38
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• 2014

AD 1세기로 추정되는 몽골 도르릭나르스 흉노 무덤에서 출토된 토기는 파단면을 따라 검은색의 유기물로 접합한 흔적이 남아있었다. 본 연구에서는 부착된 검은색 유기물의 특성을 확인하기 위해 GC-MS를 이용하여 성분분석 한 결과, 자작나무 껍질 타르의 특성 성분으로 알려진 루페올(Lupeol) 및 베툴린(Betulin) 등을 포함한 Triterpenoid 화합물이 확인되었다. 이를 통해 고대 몽골에서는 자작나무 껍질로 만든 타르를 사용하여 토기를 접합하였음을 알 수 있었다. 따라서 앞으로 고고자료에 잔존하는 유기물에 대하여 체계적인 과학적 조사가 이루어진다면 과거의 생활 모습에 대한 중요한 정보를 제공할 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제23권6호
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• pp.843-849
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• 2013

A dye-decolorizing bacterium was isolated from a soil sample and identified as Bacillus thuringiensis using 16S rRNA sequencing. The bacterium was able to decolorize three different textile dyes, namely, Reactive blue 13, Reactive red 58, and Reactive yellow 42, and a real dyehouse effluent up to 80-95% within 6 h. Some non-textile industrially important dyes were also decolorized to different extents. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometer analysis of the ethyl acetate extract of Congo red dye and its metabolites showed that the bacterium could degrade it by the asymmetric cleavage of the azo bonds to yield sodium (4-amino-3-diazenylnaphthalene-1-sulfonate) and phenylbenzene. Sodium (4-amino-3-diazenylnaphthalene-1-sulfonate) was further oxidized by the ortho-cleavage pathway to yield 2-(1-amino-2-diazenyl-2-formylvinyl) benzoic acid. There was induction of the activities of laccase and azoreductase during the decolorization of Congo red, which suggests their probable role in the biodegradation. B. thuringiensis was found to be versatile and could be used for industrial effluent biodegradation.

• 분석과학
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• 제9권4호
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• pp.399-405
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• 1996

참기름 중의 향기성분을 연속수증기증류법(SDE)과 동적헤드스페이스법(DHS)으로 포집하여 GC와 GC-MSD로 동정하였다. SDE로 분석하였을 때 alcohol 6종, aldehyde 6종, ketone 및 acid류 5종, furan 및 phenol류 4종, pyrazine 화합물 12종, pyridine 및 thiazole류 4종, 기타 9종으로 총 46종이 확인되었다. DHS로 분석한 경우 alcohol 3종, aldehyde 6종, ketone, furan 및 phenol류 6종, pyrazine류 12종, pyridine 및 thiazole 4종, 기타 5종으로 모두 36종이 확인되었다. 대부분의 화합물이 SDE법에서 분리된 것이었으나 1-hexanol, pentanal, dimethylsulfide등은 DHS법에 의해서만 분리되었다.

• 자원환경지질
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• 제40권5호
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• pp.699-703
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• 2007

가스크로마토그래피와 동위원소질량분석기를 온라인으로 연결하여 이루어지는 성분별동위원소분석기술은 지구과학, 환경과학 및 법의학 분야에서 안정동위원소 분석의 최신 기술이다. 1990년대부터 GC-IRMS는 법의학 분야에서 식품의 진위감별과 환경과학 분야의 유기오염물질의 오염원 추적에 널리 이용되어 왔다. 국내에서는 한국기초과학지원연구원에 2005년 초에 처음으로 GC-IRMS가 설치되었다. 이 연구에서는 한국기초과학지원연구원에서 운영중인 GC-IRMS를 간단히 소개하고 제조사가 다른 BTEX의 성분별탄소동위원소의 예비분석결과를 소개한다.

• Environmental Analysis Health and Toxicology
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• 제18권3호
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• pp.219-224
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• 2003

1,4-Dioxane is used as a solvent for lacquers, paints, varnish removers, dye baths and printing compositions. And it is also used for detergent preparations, cosmetics, deodorants and fumigants. A method is described for the determination of 1,4-dioxane in water samples by GC/MS. The extraction recoveries were studied for some solvents and solvent volume ratio were investigated using r-butyl methyl ether (MTBE). Optimum condition was obtained by the liquid-liquid extraction using the 10 mL of MTBE for 10 mL of water. Method detection limit of 1,4-dioxane in the 20 mL of water samples was 0.05 ng/mL. It could be determined in the range of 0.24∼240 ng/mL in treated water, and in the range of 0.69∼81.9 ng/mL in raw water, respectively. Risk assessments with 1,4-dioxane exposure by drinking water ingestion were carried out. Based on the results of analysis, chronic daily intake of 1,4-dioxane was 2.22${\times}$10$\^$-4/ mg/kg/day and excess cancer risk was calcu-lated to be 2.44${\times}$10$\^$-6/.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_3호
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• pp.107-111
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• 2001

Surface seawater was sampled from 20 stations in Youngil Bay, Korea in November 2000. The samples were analyzed for eight chlorobenzenes(CBs) out of a total of 12 in the congener series using a gas chromatography coupled to a mass spectrometer detector(GC/MSD). The total CB levels varied from 1.3 to 6.1 ng/L with a mean of 4.0 ng/L. Trichlorobenzene groups (sum of 1,3,5-, 1,2,4-, and 1,2,3-trichlorobenzene) were the predominant class among the four congener groups, while tetrachlorobenzenes(sum of 1,2,3,5-, 1,2,4,5-, and 1,2,3,4- tetrachlorobenzene) and pentachlorobenzene showed a low presence. The total CB levels exhibited similar patterns for all the stations. A significant positive correlation was observed between the individual CB compounds in the particulate samples, while the dissolved samples revealed a strong correlation between the heavier molecular weight CBs.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.459-463
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• 2009

Furoxanaldehydes possessing phenyl or alkenyl groups at the 3- or 4-position of the furoxan ring were designed for alkyne formation on a solid surface. Furoxans 2 and 3 were prepared from the corresponding alkenes 2a and 3a by the reaction with NaN$O_2$ in acetic acid. Furoxan 4, in which the furoxan ring is conjugated with a double bond, was prepared from bis(bromomethyl)benzene 4a in 5 steps using the Wittig reaction of aldehyde 1 as the key step. The electron beam-mediated fragmentation of furoxanaldehydes 1-4 in a mass spectrometer was exploited by focusing on alkyne formation on the solid surface. The fragmentation of furoxan 3 possessing diaryl groups afforded diarylacetylene at high efficiency, suggesting that the aryl group conjugated with the furoxan ring could facilitate alkyne formation with the evolution of NO.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
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• pp.117-118
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• 2006

In this work, we investigated etching characteristics of $HfO_2$ thin film and Si using inductive coupled plasma (ICP) system. The ion energy distribution functions in an inductively coupled plasma was analyzed by quadrupole mass spectrometer with an electrostatic ion energy analyzer. The maximum etch rate of $HfO_2$ is 85.5 nm/min at a $BCl_3/(BCl_3+Ar)$ of 20% and decreased with further addition of $BCl_3$ gas. From the QMS measurements, the most dominant positive ion energy distributions (IEDs) showed a maximum at 20 % of $BCl_3$. These tendency was very similar to the etch characteristics. This result agreed with the universal energy dependency of ion enhanced chemical etching yields. And the maximum selectivity of $HfO_2$ over Si is 3.05 at a O2 addition of 2 sccm into the $BCl_3/(BCl_3+ Ar)$ of 20% plasma.

• 한국기계가공학회지
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• 제9권1호
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• pp.106-113
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• 2010

The most suitable condition for plasma source ion implantation(PSII) was found based on the study of the characteristics of PSIIed tool and machined surfaces. The depth analysis according to the chemical bonding state of elements and surface component elements through the XPS and SIMS, was conducted to find the improved property of the PSIIed surface. Due to the diffusion of PSII, the nitrogen was found up to a depth of about 150nm according to the supplied voltage and ion implanted time. The deep diffusion by nitrogen caused the surface modification, but the formation of oxide component was found due to the residual gas contamination on the surface. Statistical method of ANOVA was conducted to find the effects of spindle speed and feed rate in interaction for machined surface roughness with PSIIed tools. The surface modification was found largely occurred by the nitrogen implanted surface with 2 hours for 27kV, 35kV and 43kV.