• 분석과학
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• 제12권2호
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• pp.89-93
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• 1999

적은 양의 시료를 분석할 수 있는 마이크로 컬럼 이온 크로마토그래피용 전도도 셀과 억압컬럼을 개발하였다. 안지름이 작은 모세관 컬럼을 사용하는 경우 이동상의 유속은 보통 $5{\sim}20{\mu}L/min$ 정도 된다. 따라서 이 경우 일반적인 전도도 셀은 사용할 수가 없기에 내부 부피가 작은 모세관 컬럼용 전도도 셀과 억압컬럼을 제작하였다. 전도도 셀은 두 개의 백금 피하주사 바늘을 안지름이 0.010 mm인 튜브 속에 넣어 간격이 $2{\mu}m$ 되게 만들었고, 억압컬럼은 Nafion 튜브를 이용하여 막-억압컬럼 형태로 개발하였다. 이 전도도 셀과 억압컬럼을 이용하여 실제 음이온들(플루오르화물, 아질산염, 질산염, 염소산염)을 분석한 결과 재현성 있고 양호한 크로마토그램을 얻었다.

• 한국대기환경학회지
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• 제9권2호
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• pp.147-153
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• 1993

From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.153-157
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• 1991

Intracellular enzymes of an extreme halophilic bacterium, Halobacterium sp. HE10, isolated from a saltern in Korea was investigated. The membrane-bound enzyme, NADH dehydrogenase, involved in electron transport system was stimulated by the addition of 2.0 M NaCl. The respiratory enzyme activities such as NADH oxidase and NADH dehydrogenase was decreased on removal of $Na^+$ ion and restored when replaced with cations like $K^+$, $Li^+$and $NH_{4}^{+}$ ions. Furthermore, their activities were affected by the anions such like carbonate, acetate, sulfate, chloride and nitrate at the presence of $Na^+$ion. Lactate dehydrogenase activity was highest at the asturated solution of NaCl and isocitrate dehydrogenase activity was a maximum level at 1.0 M NaCl. These results suggested that the enzyme activites of the respiratory chain in Halobacterium sp. EH10 was stimulated by the presence of $Na^+$ ion.

• 약학회지
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• 제34권3호
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• pp.215-218
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• 1990

An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.

• Macromolecular Research
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• 제16권2호
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• pp.108-112
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• 2008

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of nonpolar polymeric materials is affected by the sample preparation as well as the matrix and cationizing agent. This study examined the influence of silver salt types on the MALDI analysis of polybutadiene (PB). Silver trifluoroacetate (AgTFA), silver benzoate (AgBz), silver nitrate ($AgNO_3$), and silver p-toluenesulfonate (AgTS) were used as the silver salts to compare the MALDI mass spectra of PB. The mixture solution of PB and 2,5-dihydroxybenzoic acid (DHB), as a matrix dissolved in THF, was spotted on the sample plate and dried. A droplet of the aqueous silver salt solution was placed onto the mixture. The mass spectrum with AgBz showed the clear $[M+Ag]^+$ ion distribution of PB while the mass spectrum with AgTFA did not show $[M+Ag]^+$ ions but only silver cluster ions. The mass spectra with $AgNO_3$ and AgTS did not show a clear $[M+Ag]^+$ ion distribution. The difference in the formation of $[M+Ag]^+$ ions of PB depending on the silver salts was attributed to the silver cation transfer reaction between the silver salt and the matrix (DHB). The mass spectrum showed a clear $[M+Ag]^+$ ion distribution of PB when the conjugate acid of the silver salt was less acidic than the matrix.

• 한국식품위생안전성학회지
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• 제30권3호
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• pp.265-271
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• 2015

본 연구에서는 축산물 및 축산가공품에서 천연적으로 유래되는 질산염과 아질산염의 함유량을 조사하였다. 식육 223건, 식육가공품 51건, 원유 30건, 유가공품 142건, 알류 5건 및 알가공품 7건으로 총 458건에 대해 이온크로마토그래피(IC)를 이용하여 질산염과 아질산염을 분석하였다. 이 때, 축산물 가공기준 및 성분규격의 전처리법과 기기조건을 이용하여 분석하였으며 축산물 및 축산가공품에 적용하여 시험법 검증(직선성, 검출한계, 정량한계, 회수율, 재현성 및 측정불확도)을 실시한 결과, 모두 양호한 값으로 나타났다. 총 458건을 분석한 결과, 질산염이 167건에서 아질산염이 40건에서 검출되어 질산염이 아질산염에 비해 검출된 건수가 많았다. 질산염의 경우, 조제분유류에서 ND~40.23 mg/kg으로, 양념육류에서 ND~37.97 mg/kg으로, 가공치즈류에서 ND~32.40 mg/kg으로, 알가공품에서 4.92~31.50 mg/kg으로, 분유류에서 ND~27.73 mg/kg으로, 소시지류에서 ND~22.45 mg/kg으로, 베이컨류에서 ND~22.45 mg/kg으로, 자연치즈류에서 ND~21.55 mg/kg으로, 햄류와 발효유류에서 ND~20.82 mg/kg으로, 알류에서 ND~13.57 mg/kg으로, 버터류에서 ND~12.77 mg/kg으로, 우유류에서 ND~9.31 mg/kg으로, 식육류에서 ND~3.88 mg/kg의 순으로 나타났다. 한편, 아질산염은 알가공품에서 1.84~17.35 mg/kg으로 나타났으며 식육류에서는 ND~1.92 mg/kg의 범위로 검출되었다.

• Asian Journal of Atmospheric Environment
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• 제3권1호
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• pp.27-41
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• 2009

Internally mixed states of submicron particles during transport from the Asian continent to the Pacific Ocean were analyzed using a single-particle time-offlight mass spectrometer. The observation was conducted at Tsukuba in Japan in the spring of 2005 in order to investigate springtime transport of particles from the continent. The sum of ion intensities of sulfate (${HSO_4}^-$) detected in particles originating from the continental air masses counted for 75% of that in all particles during the observation. By analyzing correlations among compounds, origins and internally mixed states of compounds were estimated. It was found that nitrate was mixed with sulfate-rich particles as the air mass approached Japan. It was confirmed that Asian mineral dust particles played significant roles for transport of continental sulfate to Japan. As a result of analysis on internal mixing of chlorine and nitrate, it was implied that the chlorine loss in fine sea salt particles had already proceeded at Tsukuba. It was characteristic that fluoride ions were significantly detected, coal combustion in the Asian Continent can be an important source of fluorides detected in Japan through the westward transportation of fine particles including fluorides.

• 한국환경과학회지
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• 제12권2호
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• pp.217-225
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• 2003

Samples of size-fractionated PM10 (airborne particulate matter with aerodynamic diameter less than $10\mu\textrm{m}$) were collected at an urban site in Jeju city from May to September 2002. The mass concentration and chemical composition of the samples were measured. The data sets were then applied to the CMB receptor model to estimate the source contribution of PM10 in Jeju area. The average PM10 mass concentration was 28.80$\mu\textrm{g}/m^3$ ($24.6~33.49\mu\textrm{g}/m^3$), and the FP (fine particle with aerodynamic diameter less than $2.l\mu\textrm{m}$ fraction in PM10 was approximately 8% higher than the CP (coarse particle with aerodynamic diameter greater than $2.l\mu\textrm{m}$ and less than $10\mu\textrm{m}$ fraction in PM10. The CP composition was obviously different from the FP composition, that is, the most abundant water soluble species was nitrate ion in the FP, but sulfate ion in the CP. Also sulfur was the most dominant element in the FP, however, sodium was that in the CP. From CMB receptor model results, it was found that road dust was the largest contributor to the CP mass concentration (45% of the CP) and ammonium nitrate, domestic boiler, and marine aerosol were major sources to the CP mass. However, the secondary aerosol was the most significant contributor to the FP mass concentration (45% of the FP). In this study, it was suggested that the contributions of soil dust and gasoline vehicle became very low due to collinearity with road dust and diesel vehicle, respectively.

• 분석과학
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• 제11권3호
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• pp.213-221
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• 1998

Bromide, chloride, fluoride, nitrite, nitrate, sulfite, sulfate, perchlorate, chlorate 및 chlorite가 포함된 시료를 capillary zone electrophoresis(CZE)와 indirect UV detection 방법으로 분리하였다. 음이온류의 분리는 running buffer로 5 mM ammonium dichromate, 10 mM ammonium acetate, 20 mM diethylenetriamine, 10% methanol(pH 9.3)을 사용하였으며 전압은 cathode에 15 kV를 공급하였다. 또한 최초로 CZE에서 음이온의 정량이 가능하도록 각 이온들에 대한 regression과 detection limit를 결정하였고, 이 분석방법은 톨루엔을 흡입한 사람의 뇨, 부검 혈액, 폐수 및 폭약 등 시료에 적용하였으며, 음이온의 함량을 ion chromatograph(IC)와 비교 검토하였다.

• 대한화학회지
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• 제20권4호
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• pp.299-308
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• 1976

단백질 섬유인 견섬유에 ceric ammonium nitrate를 촉매로 사용하여 acrylamide 또는 acrylonitrile을 그라프트공중합 하였다. 공중합의 표준반응조건은 세륨염 0.025 M, acryamide 0.5 M, 초산 25%, 온도 30$^{\circ}C$, 반응시간 3시간으로 하였으며 견섬유의 욕비(bath ratio)는 1:200으로 하였다. 이상의 반응조건에서 세륨염의 농도가 0.01 M 일 때와 7% 초산수용액일 때에 그라프트율이 최대로 되었다. Acrylonitrile을 단위체로 사용하면 질산용액에서의 그라프트율이 초산수용액에서 보다 높았지만, acrylamide 사용시와는 달리 그라프트율은 현저히 낮았다. 이밖에 그라프트된 견섬유의 Lowe시약(동-글리세린 수용액)에 대한 용해도, 적외선 분석 및 분자량을 조사하고 호모 중합체의 생성에 대하여 검토 하였다.