• Korean Chemical Engineering Research
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• 제46권3호
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• pp.633-638
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• 2008

열화학적 물분해에 의한 수소 생산 공정 중의 하나인 IS(Iodine-sulfur) 사이클에서 요오드와 이산화황, 그리고 물을 반응물로 하여 요오드화수소와 황산을 제조하는 분젠 반응에 대한 연구를 수행하였다. 요오드의 투입 몰수에 관계없이 황산의 생성량은 일정하였으나 요오드화수소의 생성량은 요오드의 투입 몰수가 증가함에 따라 감소하는 경향을 나타내었다. 이는 생성된 요오드화수소와 미 반응된 요오드가 $HI_3$ $HI_5$ or $HI_7$와 같은 착화합물인 polyiodide를 형성하기 때문인 것으로 생각된다. 이들 착화합물의 형성은 생성물의 2액상 분리 특성의 향상을 가져온다. 또한 요오드 투입 몰수의 증가함에 따라 반응 속도는 향상되었다. 반응물인 요오드의 투입 몰수 및 반응 온도가 증가함에 따라 생성 용액의 2액상 분리 특성이 향상되었으며 모든 실험의 조건 하에서 부반응은 발생 되지 않는 것으로 나타났다.

• Nuclear Engineering and Technology
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• 제52권8호
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• pp.1638-1649
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• 2020

In the case of a severe accident in a Light Water Reactor, the issue of late release of fission products, from the primary circuit surfaces is of particular concern due to the direct impact on the source term. CsI is the main iodine compound present in the primary circuit and can be deposited as particles or condensed species. Its chemistry can be affected by the presence of molybdenum, and can lead to the formation of gaseous iodine. The present work studied chemical reactions on the surfaces involving gaseous iodine release. CsI and MoO₃ were used to highlight the effects of carrier gas composition and oxygen partial pressure on the reactions. The results revealed a noticeable effect of the presence of molybdenum on the formation of gaseous iodine, mainly identified as molecular iodine. In addition, the oxygen partial pressure prevailing in the studied conditions was an influential parameter in the reaction.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1031-1037
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• 2018

수용성 비이온고분자인 Polyvinylalcohol (PVA), Polyvinylpyrrolidone (PVP), Hydroxypropyl cellusoe (HPC)와 iodine과의 착물 형성에 대한 계면활성제의 영향을 알아보기 위해 Sodiumdodecylsulfate을 포함하는 수용액에서 이들 사이의 반응을 수행하였다. PVP와 HPC에서 tri-iodide band의 적색 이동에 의하여 착물이 만들어졌다는 것을 알게되었고, PVA-iodine 착물에서는 500 nm 부근에서 고유의 특색있는 띠를 나타내었다. SDS 계면활성제의 존재는 PVA-iodine 착물의 파괴를 가져왔고, 고유의 푸른색도 사라지게 만들었다. 그러나 SDS 단량체는 PVP, HPC와 iodine의 착물 형성을 도와주는 경향을 나타내었다. 고분자 용액에서 겔이 만들어지는 것을 방해하는 n-propanol은 고분자-iodine 착물이 형성되는 것을 도와주었다. SDS가 있을 때와 없을 경우의 영향을 알아보기 위해 순수한 HPC와 HPC-iodine 착물을 만들고 이들의 성질을 조사하였다.

• 대한화학회지
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• 제14권3호
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• pp.221-228
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• 1970

The tendency of forming a charge transfer complex between furfuryl derivatives (2-methyl furan, furfuryl acetate, and Ethyl 2-furoate) and halides(Iodine, Iodine monochloride, and Trichloro bromo methane) was studied by means of ultra violet spectrophotometry. In case of furfuryl acetate the formation of the complex could not be distinctly detected by this method. Iodine and trichloro bromo methane could show a distinct formation of charge transfer complex in the U.V. region, whereas iodine monochloride shows a possibility of forming an addition compound rather than the charge transfer complex itself. The results were discussed in conjunction with the stability of the furfuryl ring.

• 대한화학회지
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• 제19권1호
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• pp.43-49
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• 1975

소량의 요오드 화합물이 윤활류에 함유될 때 금속표면사이의 마찰을 감소시키고 내마모성을 향상시키는데 이는 금속표면에 박층상구조의 이요오드화물이 형성되기 때문이라고 한다. 그러나 금속표면에서의 화학반응성, 마모와 극압실험 및 hot wire method에 의한 결과에 의하면 윤활기구는 이 요오드화물의 박층상 구조가 아니고 다른 기구에 의한 것임을 알았다. 유기 요오드화합물중에서 특히 N-iodopyridinium dichlorodate는 double charge transfer complex로써 다른 methyl iodide계의 화합물 보다 금속표면 사이의 마찰을 더욱 감소시키고 윤활기구는 interhalogen의 화학반응에 의한 것임을 알았다.

• 대한방사성의약품학회지
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• 제3권1호
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• pp.3-14
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• 2017

Nucleophilic aromatic fluorination has been one of the most explored methods in fluorin-18 based radiochemistry. Unlike electrophilic $[^{18}F]$fluorination methods, no-carrier-added nucleophilic radiofluorination with cyclotron-produced $[^{18}F]$fluoride ion offers better specific radioactivity which is essential aspect to obtain good quality images from positron emission tomography. Contrary to amenable aliphatic radiofluorination, the development of reliable aromatic $[^{18}F]$fluorination methods has been pursued by many research groups; however, no viable method has yet been established. Recently, hypervalent iodine compound draws increasing attention as versatile radiolabeling precursor for various $[^{18}F]$fluoroarenes, since it bears the capacity to introduce fluorine-18 either on electron-deficient or electron-rich aryl ring with enhanced regiospecificity. Other classes of hypervalent iodine congeners often utilized in radiochemistry are iodylarenes, iodonium ylides, and spirocyclic iodonium ylides. Recently developed spirocyclic iodonium ylides have already been avidly employed to provide various $[^{18}F]$aryl fluorides with high labeling efficiency. This metal-free protocol would afford efficient routes, replacing the traditional approaches to $[^{18}F]$fluoroarenes, from prosthetic labeling synthons to complex PET radiotracers.

• Carbon letters
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• 제8권4호
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• pp.274-279
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• 2007

In order to understand the breakthrough behaviour of iodine vapours on impregnated carbon systems, an active carbon, 80 CTC grade, $12{\times}30$ BSS particle size and $1104\;m^2/g$ surface area, was impregnated with metal salts such Cu, Cr, Ag, Mo and Zn, and an organic compound Triethylene diamine (TEDA) to prepare different carbon systems such as whetlerite, whetlerite/TEDA, whetlerite/KI/KOH and ASZMT. The prepared adsorbents along with active carbon were characterized for surface area and pore volume by $N_2$ adsorption at liquid nitrogen temperature. These carbon systems were compared for their CT (concentration X time) values at 12.73 to 53.05 cm/sec space velocities and 2 to 5 cm carbon column bed heights. The carbon column of 5.0 cm bed height and 1.0 cm diameter was found to be providing protection against iodine vapours up to 5.5 h at 3.712 mg/L iodine vapour concentration and 12.73 cm/sec space velocity. The study clearly indicated the adsorption capacities of carbon systems to be directly proportional to their surface area values. Dead layer with all the prepared carbon systems was found to be less than 2.0 cm indicating it to be minimum bed height to have protection against $I_2$ vapours. Effect of carbon bed height and flow rate was also studied. The active carbon showed maximum protection at all bed heights and flow rates in comparison to all other impregnated carbon systems, showing that only physical adsorption is responsible for the removal of iodine vapours.

• 대한화학회지
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• 제11권2호
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• pp.51-55
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• 1967

放射性 沃化反應 中 分解하기 쉬운 化合物의 沃化反應으로 有用한 低溫沃化反應에 關하여 硏究하였다. Chloroamine-T를 利用한 沃化反應은 低溫에서 높은 收率로 放射性 沃化反應을 進行시킬 수 있었으며, 活性化된 芳香核이 있는 또는 이에 類似한 아미노酸, 蛋白質化合物, 各 種 Phenol類의 沃化가 不可能하였으나 二重結合化合物 및 一般化合物엔 큰 效果가 없었다. 反應收率은 $100{\sim}60%$이었으며, 各 化合物의 試藥에 對한 反應度는 親電子反應에 對한 芳香核의 反應度와 比例하는 것이었다. 反應操作을 記述하였으며 反應過程을 考察하였다.

• 한국응용과학기술학회지
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• 제21권4호
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• pp.359-363
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• 2004

Reaction conditions and catalysts were investigated for direct $CF_3I$ synthesis. Optimum reaction temperature was determined by pyrolysis of $CF_3H$ and catalytic reactions. Reactions with changing oxygen concentration were performed. As a result, yield of $CF_3I$ increased with decreasing oxygen concentration. Catalytic activity was changed with the weight ratio of the used metal salts. This result was stemmed from the change in the pore size of activated carbon by the metal salts. The optimum reaction conditions were: $600^{\circ}C$, space velocity of $45hr^{-1}$, and with 7wt% KF/AC catalyst.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.432-435
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• 2002

The ultimate study of this research is to improve the properties of digital X-ray receptor based on amorphous selenium. There are being two prominent studying for Digital Radiography. Direct and Indirect method of Digital Radiography are announced for producing high quality digital image. But each two systems have strength and weakness. This is a basic research for developing of Hybrid digital radiography which is a new type X-ray detector. ln this study, we investigated the electrical characteristic of multi-layer$(CaWO_4+a-Se)$ as a photoconductor according to the changing iodine composition ratio. The iodine composition ratio of a-Se compound is classified into 5 different kinds which have 30ppm, 100ppm, 300ppm, 500ppm, 700ppm and were made test sample throught thermo-evaporation. The phosphor layer of $CaWO_4$ was overlapped on a-Se using EFIRON optical adhesives. We measured the dark and photo current about the test sample and compared the electrical characteristic of the net charge and signal-to-noise ratio. Among other things, test sample of compound material of 700ppm iodine showed good characteristic of $2.53nA/cm^2$ dark current and $479nC/cm^2{\cdot}mR$ net charge at $3V/{\mu}m$.