• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.188-197
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• 1999

In order to estimate the uranium flux from seawater to sediments, we took pore water samples and deployed benthic chambers on seafloor of Chonsu Bay, Korea. The uranium flux across the sediment-water interface was estimated from the pore water to be 0.112-0.566 mg/$m^2yr$, corresponding to a removal flux of $4.3-21.5{\times}10^7$ gU/yr for the entire Yellow Sea. Nutrient fluxes from sediment to bottom water were estimated to be 135.6 mmol/$m^2yr$ for ammonia, 228.2 mmol/$m^2yr$ for nitrate, 36.8 mmol/$m^2yr$ for phosphate and 23.9 mmol/$m^2yr$ for silicate. The redox boundary, based on the distribution of pore water nitrate and solid phase manganese, was located at 3-5 cm below the sediment surface. Phosphate flux obtained by benthic chambers was 28.S mmol/$m^2yr$. On the other hand, estimates of uranium and silicate fluxes were orders of magnitude greater than those based on pore water profiles. Flux estimates on the basis of pore water concentration is believed to have greater reliability than those obtained from benthic chamber data.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.355-360
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• 1998

Reduction activity of precious metal-loaded HZSM-5 for NO has been studied and was compared to that of Cu-HZSM-5 in the presence of excess oxygen. It was found that among the catalysts used in this study, Ru-HZSM-5 was the most active catalyst for the reduction of NO to $N_2$ in the absence of hydrocarbon reductant. The highest conversion obtained was 45%. No severe inhibition of water vapor to the reduction was observed. It is suggested that the higher catalytic activity of Ru-HZSM-5 may result from the better ability to oxidize NO to $NO_2$ in the presence of excess oxygen. A proposed reaction mechanism for the reduction of NO to $N_2$ in the presence of excess oxygen is that NO is oxidized to $NO_2$ on the surface of Ru-HZSM-5 catalyst and the adsorbed $NO_2$ on the surface is then decomposed to $N_2$. $NO_2$ is supposed to the reaction.

• Clean Technology
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• v.25 no.1
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• pp.63-73
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• 2019

Numerical analysis was done to evaluate the chemical reaction and the reduction rate inside of selective non-catalytic reduction to denitrification in combustion process. The $NO_X$ reduction in selective non-catalytic reduction is converted to not only nitrogen but also nitrous oxide. Simultaneous $NO_X$ reduction and nitrous oxide generation suppressing is required in selective non-catalytic reduction because nitrous oxide influences the global warming as a greenhouse gas. The current study was performed compare the computational analysis in the same temperature and amount of NaOH, and in comparison with the previous research experiments and confirmed the reliability of the computational fluid dynamics. Additionally, controlling the addition amount of NaOH to predict the $NO_X$ reduction efficiency and nitrous oxide production. Numerical analysis was done to check the mass fraction of each material in the measurement point at the end of selective non-catalytic reduction. Experimental Value and simulation value by numerical analysis showed an error of up to 18.9% was confirmed that a generally well predicted. and it was confirmed that the widened temperature range of more than 70% $NO_X$ removal rate is increased when the addition amount of NaOH. So, large and frequent changes of the reaction temperature waste incineration facilities are expected to be effective.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.65-70
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• 1988

Synthesis and biological activity test are described for the (Z)-9-tetradecen-1-yl acetate(1) and (Z)-11-tetradecen-1-yl acetate(1) and (Z)-11-tetradecen-1-yl acetate(2), the sex pheromone of the summer fruit tortrix moth, Adoxophyes orana. 8-Bromoctan-l-ol THP ether was prepared from 8-bromoctan-l-ol. The lithium anion of 1-hexyne was alkylated with 8-bromoctan-l-ol THP ether gave 9-tetradecyn-l-ol THP ether. Catalytic hydrogenation over Pd/BaSO4 followed by deprotection afforded (Z)-9-tetradecen-l-ol. Acetylation gave (Z)-9-tetradecen-1-yl acetate(1). l0-Bromodecan-l-ol THP ether was obtained from l0-bromodecan-l-ol. In liquid ammonia with THF and HMPA as cosolvents, sodium acetylide could be alkylated with 10-bromodecan-l-ol THP ether to give 11-dodecyn-l-ol THP ether. 11-Dodecyn-l-ol THP ether was then treated with n-BuLi in THF to give the lithium acetylide, which was alkylated with bromoethane to afford 11-tetradecyn-l-ol THP ether. Catalytic hydrogenation, deprotection, and acetylative gave (Z)-11-tetradecen-1-yl acetate(2). The synthetic pheromone thus obtained was attractive to the males of the summer fruit tortrix in the field.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.530-535
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• 2009

Dicyclohexyl telluride was obtained in a high yield by the reaction of cyclohexyl bromide with NaTeH(prepared in situ) in an aqueous ethanolic solution. A series of new organotelluronium salts of the general formula ${(cyclo-C_6H_11)}_2Te(R)X$ (where R = $CH_3$, X = I (1); R = $C_2H_5$, X = Br(2); R = $C_2H_5$, X = I (3); R = C_3H_5$, X = Br (4)) were prepared by the reaction of ${(cyclo-C_6H_11)}_2Te$ with the corresponding alkyl halide. Reaction of 1 with NaBPh4 gave compound 5 ( i.e. R = CH3, X = BPh4 ‒) in 78% yield. Reaction of ${(cyclo-C_6H_11)}_2Te$ with benzyl bromide and 4-bromophenacyl bromide gave unexpectedly dibenzylcyclohexyltelluronium bromide (6) and bis(4-bromophenacyl)cyclohexyltelluronium bromide (7), respectively. Reaction of 6 with NaBPh4 gave the corresponding tetraphenylborate derivative (8) in high yield. $^1H$ NMR studies revealed that in $CDCl_3$solution compound 1 eliminated alkyl halide. Conductivity, IR, $^1H\;and\;^{13}C$ NMR and thermal data for the new compounds are presented and discussed.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.15-28
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• 2019

In accordance with the decommissioning plan for the Kori Unit 1 NPP, the reactor coolant system will be chemically decontaminated as soon as possible after permanent shutdown. This study developed the chemical decontamination process though the development project of decontamination technology of reactor coolant system and dismantled equipment for NPP decommissioning, which has been carried out since 2014. In this study, Oxidation/reduction process was conducted using system decontamination process development equipment of lab scale and was divided into unit and continuous processes. The optimal process time was derived from the unit process, and decontamination agent and the number of process were derived through the continuous processes. Through the unit process, the oxidation process took 5 hours and the reduction process took 4 hours. As optimum decontamination agent, the oxidizing agent was $200mg{\cdot}L^{-1}$ Permanganic acid + $200mg{\cdot}L^{-1}$ Nitric acid and the reducing agent was $2000mg{\cdot}L^{-1}$ Oxalic acid. In the case of the number of processes, all oxide films were removed during the two-cycle chemical decontamination process of STS304 and SA508. In the case of Alloy600, all oxide films were removed when chemical decontamination was performed for three cycles or more.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.99-110
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• 2012

The purpose of the study is to collect basis data for to establish standard administrative processes of liquid fertilizer treatment. From this survey we could make out the key point of each step through a case of effective liquid manure treatment system in pig house. It is divided into six step; 1. piggery slurry management step, 2. Solid-liquid separation step, 3. liquid fertilizer treatment (aeration) step, 4. liquid fertilizer treatment (microorganism, recirculation and internal return) step, 5. liquid fertilizer treatment (completion) step, 6. land application step. From now on, standardization process of liquid manure treatment technologies need to be develop based on the six steps process.

• Korean Journal of Microbiology
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• v.20 no.4
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• pp.183-188
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• 1982

The neurotoxin of Clostridium botulinum type B was purified from a liquid culture. The purification steps consist of ammonium sulfate precipitation of whole culture, treatment of Polymin P(0.15%, v/v), gel filtration on Sephadex G-100 at pH5.6 and DEAE-Sephadex charomatography at pH8.0. The procedure recovered 17% of the toxin assayed in the starting culture. The toxin was homogeneous by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis and had a molecular weight of 163, 000. Subunits of 106, 000 and 56, 000 molecular weight were found when purified toxin was treated with a disulfide-reducing agent and electro phoresed on SDS-polyacrylamide gels.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.235-236
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• 1999

보일러와 같은 고정원에서 배출되는 질소산화물을 제거하기 위한 후처리 기술인 선택적촉매환원공정(SCR:Selective Catalytic Reduction)은 안정적이며 탈질효율이 높아 상업적으로 가장 많이 이용되고 있다(Bosch, 1988). 본 연구팀은 가격 및 성능 측면에서 외국산 상업용 촉매와 경쟁할 수 있는 국산 SCR 촉매의 개발을 위하여 국내에서 안료용으로 생산되는 TiO$_2$를 촉매의 담체로 이용, V$_2$O$_{5}$/TiO$_2$ 하니콤 촉매를 제조하여 촉매의 활성 및 특성을 연구 중에 있다(이정빈, 1999).(중략)

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2004.07a
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• pp.45-45
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• 2004

대사작용의 개선, 정장작용과 유독 물질의 제거, 혈압과 콜레스테롤치의 정상화, 항균 및 항암효과 등 다양한 생리작용을 갖는 것으로 알려진 해조류의 기능성 규명을 위한 연구의 일환으로 총 6종(진두발, 갈래곰보 꼬시래기, 돌가사리, 고장초 톳)의 해조류의 에탄을 추출물에 대한 항산화 효과를 실험하였다. 해조류의 환원력은 시료의 첨가농도에 비례하는 경향이었으며, SOD 유사활성은 고장초의 경우 가장 높은 활성을 나타내었는데 첨가농도 500 $\mu\textrm{g}$/$m\ell$와 1000 $\mu\textrm{g}$/$m\ell$에서 각각 35.43%와 56.71%의 활성을 나타내었다. (중략)