• 수산해양기술연구
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• 제11권1호
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• pp.32-55
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• 1975

The ammonium salt of N-Nitrosophenylhydroxiamine, namely Cupferron, is a well-known analytical reagent which precipitates a great number of metal ions in acid medium. Various structures of electrode reduction for N-Nitrosophenylhydroxiamine have been suggested in acid and alkaline media by many researchers, but not in neutral medium. So the mechanism of electrode reaction of Cupferron was investigated by both chronopotentiometric and polarographic methods. It was estimated that the reduction of Cupferron occurs in a three-step mechanism through which a chemical step is interposed between two charge transfer, the ECE (charge transfer-chemical reaction-charge transfer) mechanism, over a range of neutral and alkaline media. The chemical reaction of the process was assumed to be acid-base catalyzed from the fact that kapp (over all rate constant) of chemical reaction is pH dependent.

• Macromolecular Research
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• 제14권2호
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• pp.121-128
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• 2006

Microfluidic systems have attracted much research attention recently in the areas of genomics, proteomics, pharmaceutics, clinical diagnostics, and analytical biochemistry, as they provide miniaturized platforms for conventional analysis techniques. The microfluidic systems allow faster and cheaper analysis using much smaller amounts of sample and reagent than conventional methods. Polymers have recently found useful applications in microfluidic systems due to the wide range of available polymeric materials and the relative ease of chemical modification. This paper discusses the fundamentals of microfluidic systems and the roles, essential properties and various forms of polymers used as solid supports in microfluidic systems, based on the recent advances in the use of polymers for microfluidic chips.

• Nuclear Engineering and Technology
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• 제19권4호
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• pp.242-248
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• 1987

레이저를 이용한 형광분석 방법과 형광의 세기를 증대시켜주는 'Fluran' 용액을 가함으로써 용액속에 존재하는 미량의 우라늄을 정착하고 신속하게 분석할 수 있는 새로운 장치를 개발하였다. 표준용액의 첨가 방법을 이용하여 시료의 조성 변화에 따른 형광의 방해효과를 보정할 수 있었고 5%이내의 정밀도를 갖는 0.1ppb의 측정 하한치를 얻을 수 있었다. 또한 여러 종류의 시료에 대하여 레이저를 이용한 형광분석 방법의 결과와 다른 측정 방법에 의한 결과를 상호 비교, 분석하였다.

• 대한화학회지
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• 제15권6호
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• pp.378-384
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• 1971

A new analytical reagent 8-(p-ethylbenzenesulfonamido)quinoline(EBSQ) has been synthesized, and identified its structure. EBSQ forms copper chloroform-soluble complex in a basic solution (pH = 7.5∼10.5). The other optimum conditions for the spectrophotometric study of Cu-EBSQ have been established at 380 $m{\mu}$. Beer's law is followed in the concentration range of 0~44.5 ${\mu}g$ per 10 ml of chloroform. The composition of complex has been found to be $Cu(EBSQ-H)_2$and the over-all instability constant is calculated to be $1.22{\times}10^{-7}$. The absorption coefficient of the $Cu(EBSQ-H)_2$ complex is ${\varepsilon}$ = 15,800.

• 한국수소및신에너지학회논문집
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• 제1권1호
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• pp.9-14
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• 1989

Mixed photocatalyst containing cadmium sulfide and zinc sulfide was prepared on silica gel powder and Nafion film. Photo-irradiation of aqueous mixture containing the photocatalysis generated hydrogen by water cleavage reaction. Use of sodium sulfide as sacrificial reagent help the photo-reaction. Evolution of the hydrogen was measured by gas chromatographic analysis. Composition of the catalyst was determined by atomic absorption spectrophotometer. 0.2 mL of of hydrogen was generated per hour. The maximun catalytic activity was obtained after 8-12 hours later. Hydrogen generation efficiency by the two different catalytic system was compared and showed that the Nafion-based catalyst is more efficient than the silicagel-based catalyst for the photoreaction.

• 한국군사과학기술학회지
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• 제7권3호
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• pp.110-121
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• 2004

Pyrolysis-mass spectrometry, incorporating an in situ thermal hydrolysis and methylation(THM) step, has been used to study biological materials for bacteria, toxin and virus. Newly developed pyrolyzer was used to decompose biological materials, and tetramethylammonium hydroxide(TMAH) was used as a methylation reagent. Chemical ionization(CI) using ethanol and ion trap mass spectrometer(ITMS) were used to ionize and analyze of pyrolysis components, respectively. Analytical characteristics of bacteria (including spore), virus and toxin were analyzed. Also acquisition and interpretation of mass spectra as biomarkers for classification/identification of biological material s were explained.

• 한국화재소방학회논문지
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• 제19권3호
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• pp.44-51
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• 2005

도료공업, 유기합성의 원료, 혼합용제 및 분석용 시약으로 광범위하게 이용되고 있는 메틸알콜에 대하여 작업장에서 발생할 우려가 있는 화재 폭발 예방 대책을 수립하기 위한 기초자료를 획득하기 위하여 화염전파속도와 화염도달시간을 측정하였다 용기의 크기를 변화시키고 온도 및 농도를 변화시켜 실험을 행한 결과 시료의 용기가 적을수록 연소가 용이하고 연소속도는 빠르게 나타났으며, 최대연소속도는 소용기 $30^{\circ}C$에서 200 cm/sec를 구하였다. 화염도달시간은 시료 용기의 크기가 클수록 길어지는 경향을 나타내었으며, 시료의 온도 및 농도가 높아질수록 짧아졌다.

• 대한화학회지
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• 제13권4호
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• pp.303-307
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• 1969

酸性溶液中에서 重金屬 이온의 沈澱劑로 널리 使用되는 Nitrosophenyhydroxylamine(Cupferron)의 非可逆電極反應의 電流電壓曲線과 酸性 및 알카리性에서의 還元反應機構 및 反應速度 그리고 pH變化에 따른 관여전자수, 活性化 energy를 Delahay 方法을 利用하여 구하였다.

• 약학회지
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• 제4권1호
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• pp.43-46
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• 1959

A new quantitiative analytical method of prussic acid by "Microdiffusion analysis" was studied. HCN-Glucoside of ARMENIACA was hydrolysed with KOH in out-room of unit, and then concentrated sulfuric acid was poured in order to liberate the HCN gas. The liberated gas was absorbed into nickel sulfate solution of inner room of unit quantitatively. The excess of nickel sulfate was determined by EDTA Reagent using MX-indicator. By this method, the following results were obtained: (1) It was needed more than 4 hours, in order to hydrolyse completely at $50^{\circ}C$, but could be shortened to 3 hrs. at $^60{\circ}C$. (2) It was completely absorbed into nickel sulfate solution after 30min.

• 분석과학
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• 제7권1호
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• pp.65-78
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• 1994

제초제로 사용되고 있는 농약 중 트리아진류 7종과 에스텔화된 페녹시산류 9종의 혼합물을 기체 크로마토그래피/질량분석기(GC/MS)를 이용한 선택이온 검출법(SIM)으로 동시에 분리 및 정량하는 방법을 연구하였다. 수질에 잔류하는 농약들을 $CH_2Cl_2$로 추출, 농축 및 유도체화하여 GC/MS/SIM 방법으로 분석할 때 각종 농약류의 정량 농도 범위 0.2~5.0ng/ml에서 직선성이 양호하였고 검출한계는 0.2~0.5ng/ml 범위였다. 또한 이 분석방법을 음용수 또는 생체시료에도 적용 가능하였다.