• 한국산업융합학회 논문집
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• 제4권1호
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• pp.61-69
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• 2001

Polycarbonate(PC) membranes for oxygen enrichment from air were prepared by the wet phase inversion method. In order to improve oxygen separation performances of the PC membrane, the effect of the added ethanol(nonsolvent) and $CuCl_2$(metal salt) concentration in the casting solution on morphology, oxygen permeability ami $O_2/N_2$ separation factor of the membrane was studied. In addition, tensile strength and elongation at break of the membrane were investigated. An asymmetric membrane with a dense top layer and a porous sublayer was obtained. The thickness of the dense top layer decreased with increasing amount of nonsolvent additive. Compared with pure PC membrane without additive(metal salt), the oxygen permeability and $O_2/N_2$ separation factor of the $PC/CuCl_2$ membrane are significantly improved. The oxygen permeability and $O_2/N_2$ separation factor is $5.25{\times}10^{-9}cm^3(STP){\cdot}cm/cm^2{\cdot}sec{\cdot}cmHg$ and 4.5, respectively. This improvement might be due to good interaction between metal salt and oxygen.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.335-341
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• 2018

We report the catalytic effects of metal oxides on the $CO_2$ absorption rate in an aqueous potassium salt of ${\text\tiny{L}}-lysine-HCl$ using the vapor liquid equilibrium method. The best $CO_2$ absorption rate obtained through testing metal oxides in a highly concentrated potassium salt of amino acids (2.0 M) was identified using CuO. The recyclability of the metal oxides was tested over three cycles. The catalyst CuO was found to enhance the absorption rate of $CO_2$ by 61%. A possible mechanism was proposed based on NMR spectroscopy studies. Further, the effect of change in liquid absorbent viscosity on $CO_2$ absorption is discussed.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.278-284
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• 2004

전해환원공정에서 발생하는 금속전환체와 용융염을 각각 smelting하고 고화시키는 공정을 개발하였다. 진공조건에서 다단계 가열에 의하여 마그네시아 용기에 담긴 금속전환체를 잔류 용융염과 분리하고 용융시켜 금속 잉곳을 제조하는 운전방법을 제시하는 한편, 금속전환체의 분석을 수행하였다. 전해환원 공정에서 감압이송된 용융염의 경우에는 이송과 계량에 적합하게 이중 용기와 염밸브를 사용하여 일정 형상과 크기로 고화하는 신개념을 도출하였다. 본 연구의 결과는 한국원자력연구소 Advanced Spent Fuel Conditioning Process의 hot cell 실증시스템 설계에 적용되었다.

• 방사성폐기물학회지
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• 제20권1호
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• pp.43-63
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• 2022

The aim of this review is to communicate some essential knowledge of the underlying mechanism of the corrosion of structural containment alloys during molten salt reactor operation in the context of prospective online monitoring in future MSR installations. The formation of metal halide species and the progression of their concentration in the molten salt do reflect containment corrosion, tracing the depletion of alloying metals at the alloy salt interface will assure safe conditions during reactor operation. Even though the progress of alloying metal halides concentrations in the molten salt do strongly understate actual corrosion rates, their prospective 1^st order kinetics followed by near-linearly increase is attributed to homogeneous matrix corrosion. The service life of the structural containment alloy is derived from homogeneous matrix corrosion and near-surface void formation but less so from intergranular cracking (IGC) and pitting corrosion. Online monitoring of corrosion species is of particular interest for molten chloride systems since besides the expected formation of chromium chloride species CrCl₂ and CrCl₃, other metal chloride species such as FeCl₂, FeCl₃, MoCl₂, MnCl₂ and NiCl₂ will form, depending on the selected structural alloy. The metal chloride concentrations should follow, after an incubation period of about 10,000 hours, a linear projection with a positive slope and a steady increase of < 1 ppm per day. During the incubation period, metal concentration show 1^st order kinetics and increasing linearly with time^1/2. Ideally, a linear increase reflects homogeneous matrix corrosion, while a sharp increase in the metal chloride concentration could set a warning flag for potential material failure within the projected service life, e.g. as result of intergranular cracking or pitting corrosion. Continuous monitoring of metal chloride concentrations can therefore provide direct information about the mechanism of the ongoing corrosion scenario and offer valuable information for a timely warning of prospective material failure.

• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 추계 총회 및 국제학술발표회
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• pp.75-78
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• 2000

• 한국주조공학회지
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• 제17권4호
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• pp.402-410
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• 1997

Developing a salt core for squeeze casting process, two different salt cores(pure salt core and mixed salt core) were fabricated and investigated. Pure salt core was composed of 100% NaCl and mixed salt core was made by mixtures of NaCl with MgO(1%), $Na_2B_4O_7$(2%), and talc(1%) as a binder or a strengthening agent. Salt cores were compacted to various theoretical density, heat treated, and then squeeze-cast with molten Al alloy(AC8A). The compression strength of salt cores were measured and the squeeze-cast products were examined for shape retention, infiltration of molten metal into the cores, and microstructures. The shape of salt core compacted at above 75% of the theoretical density was maintained stably. The higher theoretical density of salt cores gave higher compression strength, and the compression strength of mixed salt core was higher than that of pure salt core. Namely at 90% theoretical density, the compression strength of mixed salt core was $6.3 kg/mm^2$, compared to $4.6 kgmm^2$ for pure salt core. At a squeeze casting pressure of $1000 kg/cm^2$, molten Al alloy was infiltrated into pure salt core of under 85% of the theoretical density. At squeeze casting pressure of $1000 kg/cm^2$, only mixed salt core above 90% of the theoretical density were valid, but the shape of the core was altered in the case of pure salt core at 90% of theoretical density. A key factor for developing a salt core for squeeze casting process was estimated as the ultimate compressive strength of salt core.

• 한국식품영양과학회지
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• 제41권7호
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• pp.1014-1019
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• 2012

전국 염전에서 생산된 갯벌천일염의 수분함량과 함수 및 염전 저수지 해수에 포함된 중금속(수은, 납, 카드뮴, 비소, 구리) 함량을 평가하였으며, 생산지역에 따른 갯벌천일염의 중금속 함량 차이를 비교 분석하였다. 갯벌천일염의 수분함량은 7.357%에서 14.862% 범위였으며, 중금속 함량은 생산지역에 따라 차이가 있었으나, 비소함량은 0.007 ppm에서 0.497 ppm 수준으로 기준치를 초과한 함량은 검출되지 않았으며, 카드뮴은 불검출에서부터 0.101 ppm, 납은 불검출에서부터 0.191 ppm, 수은은 0.006 ppb에서 0.180 ppb 수준으로 기준치를 초과한 시료는 검출되지 않았다. 천일염의 구리함량은 0.039 ppm 수준에서 4.794 ppm 수준의 범위를 나타내었으며, 지역에 따라 다소 높은 수준의 함량이 검출되었다. 염전 저수지 해수에 포함되어 있는 비소함량은 불검출에서 0.474 ppm 수준이었으며, 카드뮴은 불검출에서 0.009 ppm, 납은 0.005 ppm에서 0.038 ppm, 수은은 불검출에서 0.018 ppb, 구리함량은 0.267 ppm 수준에서 3.184 ppm 수준의 범위였다. 전국 염전 함수에 대한 비소함량은 0.012 ppm에서 0.914 ppm, 카드뮴은 불검출에서 0.021 ppm, 납은 0.010 ppm에서 0.094 ppm 수준의 범위였으며, 수은은 불검출에서 0.0221 ppb, 구리함량은 0.372 ppm 수준에서 3.275 ppm 수준을 나타내었으며, 모든 시료에서 기준치를 초과한 함량은 검출되지 않았다. 이상과 같은 결과로부터 전국 염전에서 생산된 천일염, 함수 및 해수에 포함된 중금속 함량은 안전한 수준인 것으로 판단되지만 염전 결정지 바닥재로 사용하고 있는 PVC의 잠재적인 위해성을 감안한다면 이에 대한 지속적인 관리가 절실히 요청된다.

• 대한화학회지
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• 제66권2호
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• pp.75-77
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• 2022

• 식물조직배양학회지
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• 제27권4호
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• pp.325-337
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• 2000

All living organisms depend on soil and water for their sustained growth and development. In recent years, sustenance of life in these growth matrices has been adversely affected by the cumulative increase in environmental pollutants resulting from increasing population, growing economies and resource-use. This review provides a glimpse into the problem of global environmental pollution, the traditional technologies available for remediation and the scope of emerging‘plant-based remediation’technologies. Phytoremediation, the use of plants to effectively remove or stabilize contaminants from the growth substrate, is a low cost and ecologically friendly alternative to the common‘dig and dump’technologies. The field of phytoremediation has been driven by the intrinsic need for identification of ideal candidate plant species. To date, there are only a very few identified plants which satisfy all of the prerequisites for use in phytoremediation. The review focuses on one such plant species, the common horticultural plant scented geranium (Pelargonium sp.), with demonstrated potential to remediate metal / salt contaminated soils / aqueous systems. The characterization of tolerance and metal / salt accumulation potential of Pelargonium sp. and its efficacy in remediating complex contaminated sites are described. The unique ability of scented geraniums to tolerate excessive amounts of multi-metals, hydrocarbon and salt mixtures, and at the same time to accumulate significant amounts of metal and salt ions in the biomass, renders this plant species as one of the ideal candidates for remediation.

• 대한화학회지
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• 제67권4호
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• pp.222-225
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• 2023

Metallic salts of C10-18 aliphatic carboxylic acids were prepared and their scanning electron microscopic images were analyzed for the morphology dependency with the metal and the carboxylic acid. Regardless of metal ion, metal salts of dicarboxylic acids showed a high crystallinity with a fiber image (SuA-Na). The aromatic dicarboxylates also represented a morphology of a rectangular-rod or board shapes (IA-Li, IA-Ba). With Na ion, most aliphatic carboxylate (MA, PA, SA) showed a fiber-like crystallinity. However, other monovalent Li, K and multivalent Mg, especially Al ion resulted a glassy-amorphous in the metallic salts of acids (MA, PA, SA). With divalent Ba and Ca ions, the metal salt of aliphatic acids expressed a branched round cluster shape as in SA-Ca, SA-Ba. Both Li and Mg ions with a similar size showed a strong morphological similarity in the metallic salts of aliphatic acids MA, PA, SA. In the case of Na and Ca ions with a similar size (98, 106 pm), both ionic salts of stearic acid gave a branching effect for a fiber or round granular image. In the case of hydroxyl-aliphatic acids (HLA, HPA, HSA), the fiber images in HLA-Na and HSA-Na was appeared about 100 nm thicker than those of nonhydroxycarboxylates (LA-Na, SA-Na). The metallic salts of unsaturated C-18 carboxylic acids (OlA, LeA and LnA) showed an amorphous glassy image due to a kinked carbon chain.