• 한국수산과학회지
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• 제40권2호
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• pp.63-67
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• 2007

To prevent food poisoning after ingesting sea snails containing tetramine we measured the tetramine $[(CH_3){_4}N^+]$ contents of sea snails from the Korean coast using both ion chromatography (IC) and spectrometry. In total, 177 sea snails were collected from the east (Pohang, 19 species, 95 individuals), the west (Gunsan, 4 species, 46 individuals), and the south (Tongyeong, 8 species, 36 individuals) coasts. The working solution of tetramine standard for IC and the tetramine extract from the salivary gland of Neptunea arthritica cumingii were very stable for one month at $18^{\circ}C,\;4^{\circ}C$, and room temperature. The tetramine content was high in the salivary gland of Heptunea species such as N. intersculpta $(9,813{\mu}g/g)$, N. arthritica $(8,240{\mu}g/g)$, N. arthritica cumingii $(6,967{\mu}g/g)$, N. eulimata $(6,946{\mu}g/g)$, N. constricta $(5,965{\mu}g/g)$, and N, amianta $(4,502{\mu}g/g)$. The mid-gut gland and muscle contained small amounts of tetramine. The tetramine content was highest in the autumn, but no clear regional variations were observed.

• 한국식품위생안전성학회지
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• 제3권4호
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• pp.211-215
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• 1988

아황산염류는 표백, 살균, 간별 방지 및 황산화 등의 목적으로 식품첨가물로 많이 사용되고 있다. 이러한 아황산염류의 시험 방법은 우리나라 보사부의 공정시험으로 지정된 적정법과 비색법 이외도 GLC, HPLC, AAS 등을 이용한 많은 분석방법들이 연구되어 왔으나 그 정밀도, 검출한계, 안정성 등에 많은 문제가 있다. 이에 저자 등은 IC를 이용하여 아황산염류를 신속하고 정확하게 정량할 수 있는 방법을 모색하여 다음과 같은 결과를 얻었다. 1) I.C를 이용하여 $SO_2^{-2}$로서 0.2ppm까지 검출할 수 있었으며 분석기산은 20분 이내였다. 2) 흡수액은 아호아산이온의 안정성을 고려하여 3% $H_2O_2$을 사용함으로써 안정한 황산이온으로 산화시켜 정량하였다. 3) 증류수에 표준액을 첨가한 후 증류하여 측정한 회수율은 99.8%로 양호하였으나 실제 식품에 첨가한 경우는 식품의 종류에 따라 회수율의 차이가 있었다.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3206-3210
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• 2013

This study focused on the matrix interference for the qualitative and quantitative analysis of inorganic arsenic species in seaweed by ion chromatography (IC) combined with inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The matrix of seaweed has a significant effect on the determination of inorganic arsenic species. In particular, the retention times of inorganic arsenic species in the in the standard solution were different from those in seaweed because of the matrix interference. Thus, it was not suitable to use the chromatographic method for the determination of the arsenic species in seaweed. We investigated an alternative method for the determination of inorganic arsenic species in seaweed. The method was applied for the seaweed samples such as laver, green laver, sea tangle and sea mustard. The sample extraction methods of the arsenic species were also investigated in this study.

• 한국건축시공학회지
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• 제23권3호
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• pp.221-229
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• 2023

본 연구에서는 모르타르 내 침투 염화물과 황산염 분석을 단면 깊이별 용출액을 대상으로 음이온교환막(AEM)과 LIBS를 활용하여 수행하였다. 염화물(황산염) 농도별로 침지한 모르타르를 대상으로 IC 분석과 LIBS 분석을 동시에 진행하였다. 실험 결과로, Cl(837.59nm) 및 S(921.3nm)의 파장에서 AEM은 동일 침투 농도에서 paper substrate보다 높은 LIBS 강도가 측정되었고, LIBS 강도와 Cl농도 사이의 높은 상관관계가 확인되었다. 동일 깊이 IC 분석 농도 결과와 비교할 때, AEM을 활용하여 높은 강도를 얻을 수 있었다. AEM을 통해 저농도 구간의 LIBS 강도 향상과 오차 저감을 확인하였으나, S(921.3nm)의 경우는 저농도 구간에 대한 LIBS 신호 감도의 향상이 향후 필요할 것으로 보인다.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.154-157
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• 2003

A peptide inhibiting HIV-1 pretense was isolated from the hydrolysate of manila clam (Ruditapes philippinarum) proteins digested with thermolysin. The peptide was purified by using membrane filtration, gel permeation chromatography, ion exchange chromatography, and reverse phase HPLC, The amino acid sequence of the peptide was determined to be Ile-Tyr-Glu-Gly. This tetrapeptide sequence exists in some proteins of Physarum polycephalum and Mycobacterium smegmatis. Chemically synthesized Ile-Tyr-Glu-Gly showed the $IC_{50}$/ value of 22.3 $\mu$M.

• 분석과학
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• 제29권5호
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• pp.219-224
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• 2016

A sensitive method to detect trace anions in hydrofluoric acid (HF) by solid-phase extraction (SPE) clean-up and ion chromatography (IC) was described. Fluoride in HF solution was eliminated with solid-phase extraction, and residual fluoride, acetate, chloride, bromide, nitrate, phosphate and sulfate were consecutively separated with IC. The SPE parameters (selection of adsorbent, sample volume and pH, elution solvent and its volume) were optimized and selected. The removal effect of fluoride in HF solution was the best on Oasis WAX column, and the optimum conditions (1.0 mL of 25 % HF solution and 50 mM ammonium acetate 5 mL as elution solvent) were established by the variation of parameters. Under the established condition, the method detection limits of chloride, bromide, nitrate, phosphate, and sulfate were 0.04~0.30 µg/L in 25 % HF solutions (w/w) and the relative standard deviation was less than 5 % at concentrations of 20.0 and 40.0 µg/L. The concentrations of anions in a 25 % HF had detectable levels of 4.2 to 47.5 µg/L. The method was sensitive, reproducible and simple enough to permit the reliable routine analysis of anions in HF solution used in the process of producing semiconductors.

• Asian-Australasian Journal of Animal Sciences
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• 제17권11호
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• pp.1608-1614
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• 2004

This study was performed to evaluate the accuracy, validation and applicability of UV spectrophotometer (UV), Ion Chromatography (IC), and Detector tube (DT) methods for measuring ammonia (NH3) concentration in a swine confinement house and swine slurry storage tank. The mean values of $NH_{3}$ emitted from the house and slurry were 5.333 ppm and 42.192 ppm for the IC method; 4.13 ppm and 36.29 ppm for the Detector tube; and 5.417 ppm and 34.193 ppm for the UV method. The accuracy and the correlation of an ammonia level analyzed by the IC method compared to the UV method were 98% and 0.998($R^{2}$) in the swine confinement house and 94% and 0.997($R^{2}$) in the swine slurry storage tank. On the other hand, those of ammonia level measured by the Detector tube compared to the UV method were 77% and 0.957($R^{2}$) in the swine confinement house and 82% and 0.941($R^{2}$) in the swine slurry storage tank. This indicated that the accuracy and the correlation of the IC method compared to the UV method were higher than those of the Detector tube method compared to the UV method. Therefore, it was concluded that the IC method was more accurate in measuring ammonia concentration in a swine house and a swine slurry storage tank. The Detector tube method should not be applied to the swine slurry storage tank in which ammonia concentration is generally higher than 30 ppm because low accuracy is caused by a gross space between scales inscribed in the Detector tube.

• 대한환경공학회지
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• 제37권4호
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• pp.197-203
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• 2015

최근 들어 미세먼지에 의한 건강위해성에 대한 많은 문제가 지적되고 있다. 따라서 서울지역은 미세먼지를 줄이기 위한 합리적인 대책과 해결방안이 시급한 실정이다. 미세먼지의 악영향을 줄이기 위해서 우선 미세먼지의 구성성분 중 비율이 가장 많은 이온성분에 대한 명확한 해석이 선결되어야 하고, 이를 바탕으로 미세먼지의 특성을 파악하여 효과적인 저감 대책 수립 및 실천이 진행되어야 한다. 미세먼지 중 이온성분에 대한 물리화학적 특성을 해석하기 위하여 먼저 서울지역에서 미세먼지를 필터에 채취하고 이온성분 분석을 하였다. 그리고 이온크로마토그래피(IC)로 분석이 되지 않는 수소이온($H^+$)과 탄산이온${CO_3}^{2-}$)은 pH와 음이온과 양이온의 당량비 차이로 농도를 추정하였다. 질량수지를 기본원리로 하는 수학적 모델링 적용 결과 음이온과 양이온의 결합형태를 도출할 수 있었다. 미세먼지의 결합에 사용된 이온은 IC로 분석한 8개 이온과 추가로 해석한 $H^+$, ${CO_3}^{2-}$이며, 본 연구에서 나온 존재형태는 $NH_4Cl$, $NH_4NO_3$, $CaSO_4$, $(NH_4)_2SO_4$, $NaNO_3$, NaCl, $Na_2CO$, 그리고 $(NH_4)_2CO_3$ 등이 주를 이루고 있는 것으로 추정되었다.

• Tribology and Lubricants
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• 제15권4호
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• pp.335-342
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• 1999

Corrosion of the disk has been an ongoing concern for the manufacturers of hard disk drives. With the advent of magnetoresistive (MR) head, very low levels of corrosion and contamination become more critical since the raised defects and corrosion products on the disk surface-anything that heats the MR sensor due to the contact-can distort the output signal of the head. This phenomenon is called as thermal asperity. In this paper, the effect of corrosion as a form of Co migration on the occurrence of thermal asperity in MR drives was investigated. The corrosion test at high temperature (60$^{\circ}C$) and high relative humidity (80%) was emphasized in this study and the testing results at ambient condition were compared. The corrosion on the disks was characterized as the amount of Co ion migration using an ion chromatography (IC) and a time-of-flight secondary ion mass spectroscopy (TOF-SIMS). It is proved that corrosion on the disk surface after storage testing is closely correlated to the amount of Co ions migration from the magnetic layer to disk surfaces and higher Co migration causes more thermal asperities in the drive. In order to reduce Co migration, several methods such as burnishing process and structure of the carbon overcoat were investigated. It is found that the hydrogenated carbon overcoat shows the least Co migration among different types of overcoat layer. However, the most effective way to reduce Co migration is the application of Cr layer between the overcoat and the magnetic alloy layer.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.783-786
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• 2009

Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and ion chromatography(IC) were employed to analyze the thermal behavior of $Li_xCoO_2$ cathode material of lithium ion battery. The mass loss peaks appearing between 60 and 125 ${^{\circ}C}$ in TGA and the exothermic peaks with 4.9 and 7.0 J/g in DSC around 75 and 85 ${^{\circ}C}$ for the $Li_xCoO_2$ cathodes of 4.20 and 4.35 V cells are explained based on disruption of solid electrolyte interphase (SEI) film. Low temperature induced HF formation through weak interaction between organic electrolyte and LiF is supposed to cause carbonate film disruption reaction, $Li_2CO_3\;+\;2HF{\rightarrow}\;2LiF\;+\;CO_2\;+\;H_2O$. The different spectral DSC/TGA pattern for the cathode of 4.5 V cell has also been explained. Presence of ionic carbonate in the cathode has been identified by ion chromatography and LiF reported by early researchers has been used for explaining the film SEI disruption process. The absence of mass loss peak for the cathode washed with dimethyl carbonate (DMC) implies ionic nature of the film. The thermal behavior above 150 ${^{\circ}C}$ has also been analyzed and presented.