• Nuclear Engineering and Technology
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• 제32권5호
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• pp.504-513
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• 2000

The adsorption characteristics of methyl iodide generated from the simulated off-gas stream on various adsorbents such as silver ion-exchanged zeolite (AgX), zeocarbon and activated carbon were investigated. An extensive evaluation was made on the optimal silver ion-exchanged level for the effective removal of methyl iodide at temperature up to 38$0^{\circ}C$. The degree of adsorption efficiency of methyl iodide on silver ion-exchanged zeolite is strongly dependent of silver ion-amount and process temperature. The influence of temperature, methyl iodide concentration and silver ion-exchanged level on the adsorption efficiency is closely related to the pore characteristics of adsorbents. It would be facts that the effective silver ion-exchanged level was about 10 wt%, based on the degree of silver utilization for the removal of methyl iodide.

• Nuclear Engineering and Technology
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• 제16권3호
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• pp.161-168
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• 1984

습윤 조건하에서 triethylenediamine (TEDA) 합침황성탄소층의 시간에 따른 methyl iodide제거 효율을 예측하기 위한 흡착모델이 제안되었다. 습윤 조건하에서 평형 흡착용량과 유효 가공 확산 계수의 감소가 고려되었다. 예측된 값은 실험결과와 비교되었다.

• Carbon letters
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• 제2권1호
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• pp.9-14
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• 2001

Adsorption and desorption characteristics of methyl iodide at high temperature conditions up to $250^{\circ}C$ by TEDA-impregnated activated carbon, which is used for radioiodine retention in nuclear facility, was experimentally evaluated. In the range of temperature from $30^{\circ}C$ to $250^{\circ}C$, the adsorption capacity of base activated carbon decreased sharply with increasing temperature but that of TEDA-impregnated activated carbon showed higher value even at high temperature ranges. Especially, the desorption amount of methyl iodide on TEDA-impregnated carbon represented lower value than that on unimpregnated carbon. The breakthrough curves of methyl iodide in the fixed bed packed with base carbon and TEDA-impregnated activated carbon at high temperature were compared. TEDA-impregnated activated carbon would be applicable to adsorption process up to $150^{\circ}C$ for the removal of radioiodine in a nuclear facility.

• 공업화학
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• 제7권1호
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• pp.118-128
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• 1996

양이온성 천연 고분자 전해질인 chitosan의 수용성 유도체를 제조하기 위해 chitosan에 먼저 Schiff's base를 형성시키고, 이를 다시 환원시키는 방법으로 chitosan에 N-methyl, N-butyl, N,N-dibutyl기를 각각 도입시킨 후, NMP중에서 methyl iodide를 이용하여 4차 ammonium 기가 도입된 chitosan 유도체를 합성하였다. 이 반응에서 선택적인 N-alkyl 유도체 뿐 아니라 O-alkyl 또한 진행됨을 확인하였다. 제조한 각 4 차 ammonium기가 도입된 chitosan 유도체의 응집성능을 검토하기 위해 제지공장 폐수를 대상으로 응집실험을 행한 결과, chitosan 에서와는 달리 거의 모든 pH 영역에서 일정하게 뛰어난 투과도와 COD 제거율을 보였으며, alkyl 기의 탄소수가 증가할수록 응집능은 증가되었고 그 중에서도 N-butyl dimethyl chitosan ammonium iodide가 가장 우수하였다. 그러나 N-dibutyl methyl chitosan ammonium iodide는 오히려 chitosan 자체보다 감소하는 경향을 나타내었다.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1519-1523
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• 2021

Radioactive iodine (¹³¹I) released from nuclear power plants has been a critical environmental concern for workers. The effective trapping of radioactive iodine isotopes from the off-gas stream generated from nuclear facilities is an important issue in radioactive waste treatment systems evaluation. Numerous studies on retaining methyl iodide (CH₃I¹³¹) by impregnated activated carbons under the high content of moisture have been extensively studied so far. But there have been no good results on how to remove methyl iodide at high humid conditions up to now. A new challenge is to introduce other promising impregnating chemical agents that are able to uptake enough radioactive methyl iodide under high humid conditions. In order to develop a good removal efficiency to control radioiodine gas generated from a high humid process, activated carbons (ACs) impregnated with triethylene diamine (TEDA) and qinuclidine (QUID) were prepared. In addition, the removal efficiencies of the activated carbons (ACs) under humid conditions up to 95% RH were evaluated by applying the standard method specified in ASTM-D3808. Quinuclidine impregnated activated carbon showed a much higher decontamination factor above 1,000, which is enough to meet the regulation index for the iodine filters in nuclear power plants (NPPs).

• Archives of Pharmacal Research
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• 제17권2호
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• pp.60-65
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• 1994

Reaction of c-chloro-9-benzyl-8-(methylthio)purine 3 with primary amines afforoded, the comesponding 6-(substitutedamino)purines 4a-g. The latter products when methylated with methyl iodide yielded smoothly $N^3$-methyl purinium iodide salts 5a-f rather than the probable $N^1\;and\;N^7$-derivatives. 9-Benzyl-3-methyl-6-(methylmino)-8-(methylthio)purine 8 was obtained upon treating the purinium iodide 5a with alkali. Most of the synthesized compounds were screened for their antitumor activity.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.13-16
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• 2000

• 대한화학회지
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• 제33권4호
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• pp.419-425
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• 1989

1,2,4-Triazine 유도체들을 acetone 용매하에서 methyl iodide와 반응시켜 다양한 1-methyl-1,2,4-triazinium iodide 염을 합성하였다. 또한 이들 염을 10% NaOH 수용액 내에서 $K_3Fe(CN)_6$로 산화시킨 결과 고리 축소화반응이 일어나 1-methyl-1,2,4-triazole 유도체를 주로 얻을 수 있었으나 $C_6$에 치환기가 없을 경우는 미량이긴 하지만 1,6-dihydro-6-oxo-1,2,4-triazine 유도체도 동시에 얻을 수 있었다. 고리 축소화반응은 $OH^-$에 의해 먼저 pseudo base를 형성하고 이 Pseudo base가 1-methyl-1,2,4-triazole과 1,6-dihydro-6-oxo-1,2,4-triazine으로 진행됨을 확인할 수 있었고 또한 1,2,4-triazine의 3개의 질소원자 중 $N_1$ 원자에 quaternization됨을 확인할 수 있었다.

• 약학회지
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• 제33권4호
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• pp.219-225
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• 1989

2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-methyl 5-(2'-methylthio)ethyl ester methyl iodide salt (7a) was hydrolyzed by treatment with NaOH in aquous EtOH solution to give 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid mono methyl ester (2b) in 88% yield. By the same procedure, 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridinine-3,5-dicarboxylic acid 3-mono isopropyl ester (2c), 2,6-dimethyl-4-(2'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-mono methyl ester (2d), 2,6-dimethyl-4-(2',3'-dichlorophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-mono methyl ester (2e) and 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridin-3,5-dicarboxylic acid (2f) were obtained from the methyl iodide salts in 91-98% yield.

• 방사성폐기물학회지
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• 제1권1호
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• pp.65-72
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• 2003

원자력시설에서 방사성요오드 제거용으로 사용되는 TEDA 첨착활성탄의 고온공정에서치 메틸요오드의 제거성능을 은이온제올라이트(AgX)와 상호 비교하였다. 3$0^{\circ}C$-40$0^{\circ}C$ 온도범위에서 온도에 따른 메틸요오드의 흡착량 및 탈착후 잔존량을 측정한 결과, 비첨착활성탄의 흡착성능은 온도가 증가함에 따라 급격히 감소하지만 TEDA 첨착활성탄의 흡착성능은 10$0^{\circ}C$ 부근에서도 AgX-10과 거의 유사한 값을 나타내었고, 탈착후 잔존량은 25$0^{\circ}C$ 까지도 비첨착활성탄에 비하여 매우 높은 값을 유지하였다. 또한 10$0^{\circ}C$ 이상의 고온공정에서 AgX 및 TEDA 첨착활성탄을 충전한 고정층 파과특성을 상호 비교한 결과 10$0^{\circ}C$ 이상에서 AgX-10의 메틸요오드 흡착량 및 잔존량은 TEDA 첨착활성탄에 비하여 평균 30%정도 높은 값을 나타내어 고온에서 더 흡착성능이 우수함을 보여주고 있다. 흡착반응 후 생성된 기체의 성분을 분석한 결과를 토대로 AgX-10 흡착제를 충전한 고정층에서 메틸요오드 제거 메카니즘을 제안하였다.