LiCl-KCl eutectic possesses unique properties such as a low melting point, high thermal conductivity, and good electrical conductivity. These properties make it suitable for various applications, including nuclear power generation, pyroprocessing in nuclear waste management, and thermal energy storage systems. In most experiments using LiCl-KCl, the molten salt composition is an important factor; therefore, periodic analysis through sampling is necessary for monitoring compositional changes. Although manual sampling is typically used, it is time-consuming and can introduce errors due to low reproducibility. To address this issue, we have developed an automatic molten salt sampling device using the cold-finger method. This method involves immersing the tip of a tungsten rod in hightemperature LiCl-KCl, removing it after a few seconds, and allowing the adhered molten salt to solidify instantly. A collector then scratches and drops the solidified sample. These processes are carried out automatically using servo motors, enabling the sampling device to move around the molten salt system. We have optimized the sampling conditions, such as insertion and withdrawal rate, immersion time, and the interval between continuous sampling, based on the molten salt temperature. The temperature was set between 500°C and 850°C, considering the operating temperatures of the applications. In addition to sampling speed, the sampling depth is a key condition for determining the sampling mass. Therefore, we examined the amount of sample depending on the sampling depth and, particularly, considered the change in salt height when sampling is performed continuously. As a result, we determined the number of sampling iterations required to reach the target sample mass. Furthermore, to minimize the initial salt loss, we noted that sampling from the salt surface resulted in less representative samples. To determine the reliability, we compared the results of surface sampling with those obtained when sampling at the middle of the salt. This study will enable highly reproducible and reliable sampling by providing a prototype for an automatic sampling device for molten salt along with guidelines.

Viscosity is a fundamental physical property that is important in any system in which fluid movement occurs. In addition, most of the elements exist as ions in molten state in high-temperature molten salt, and electrical conductivity in such molten state is closely related to viscosity as a transport property. Molten salt reactor (MSR) and pyroprocess are representative processes dealing with high-temperature molten salts, actinide elements, and other radioactive materials. In MSR and pyroprocesses, the viscosity data must be provided as one of the fundamental physical property data required for safe process operations and countermeasures to severe accidents. In order to measure the viscosity of highly corrosive molten salt at high temperatures, we have built a in-house developed molten salt viscosity measurement system based on the Brookfield rotationary viscometer. We also developed a special correction technique to improve the accuracy of the viscosity measurement. In this study, the viscosity was measured at 500°C for NaCl-MgCl2 molten salt, which is selected as the base salt material of MSR system under development in Korea Atomic Energy Research Institute (KAERI), using our viscosity measurement system installed in a oxygen- and moisture-free Ar-atmosphere glovebox. Our viscosity measurement system was calibrated using a LiCl-KCl eutectic mixture with well-known viscosity value, and viscosity values obtained using our own correction methodology were compared with those of other conventional correction methods. In our further study, we plan to measure the NaCl-MgCl2-UCl3 system at various compositions and temperatures.

Electroanalytical study for the rotating cylinder electrode in molten LiCl-KCl eutectic salt (58– 42mol%) containing MgCl2 (0.1wt%) at 600°C is conducted. The researches of rotating cylinder electrode have been widely conducted for the century. The advantage of the electrode is that it can mitigate the unintended natural convection by providing a controlled diffusion boundary layer thickness. However, the experimental data for the high temperature molten salts is barely existed. The study adopts the electrochemical techniques such as cyclic voltammetry for the static cell and linear sweep voltammetry for the dynamic cell to calculate the diffusion coefficient. The peak current density and limiting current density are measured according to the scan rate. In order to evaluate the mass transfer under hydrodynamic flow condition, the revolution speeds of cylindrical electrode are varied from 10 rpm to 500 rpm which are corresponded to the Reynolds number of 4 and 185 respectively. The flow regime covers from the laminar to semi-turbulent regime (transient) as the critical Reynolds number Recrit is 200. The limiting current density shows a linear trend with the revolution speed and agrees well with the existing mass transfer correlations. For the extended flow regime, a new mass transfer correlation is suggested as the relation of non-dimensional numbers (Sh = aRebScc) based on the dimensionless analysis.

In this work, the sulfonic acid group was introduced into the resorcinol–formaldehyde (RF) microspheres by the addition of p-phenolsulfonic acid during the polycondensation process of RF. The hydrophilicity of the sulfonated RF allowed KOH to infiltrate inside the microspheres, which enhanced the formation of mesopores in the carbon microspheres during the activation process by KOH. SEM and TEM observations and N2 adsorption measurements verified the formation of abundant mesopores in the porous carbon microspheres. The BET surface area of these mesoporous carbons exceeded 2000 m2/ g. In 17 m NaClO4 “water-in-salt” (WIS) electrolyte-based supercapacitor, the synthesized mesoporous carbon exhibited high specific capacitance of 170 F/g at current density of 0.5 A/g, comparable to those in regular KOH electrolyte. When graphite was used as current collectors, the symmetric cell could operate at 2.5 V, and the mesoporous carbon exhibited an energy density of 43 Wh/kg at power density of 0.25 kW/kg, and 25 Wh/kg at power density of 6.25 kW/kg, respectively, which were superior to those using Pt or stainless steel as current collectors. The mesoporous carbon/graphite was an excellent electrode in new-generation “WIS” electrolyte-based high-voltage supercapacitor due to their high energy and power density.

Excessive intake of sodium caused by high salt diet promotes the expression of inflammatory cytokines and differentiation of helper T cells resulting in inflammatory responses. High-glucose diet also contributes to the pathogenesis of periodontitis by inducing changes in the oral microbiome and reducing salivation. However, the effect of a high-salt and glucose diet (HSGD) on the prognosis of periodontitis remains unclear. In this study, a rat model of experimental periodontitis was established by periodic insertion of absorbable sutures containing Porphyromonas gingivalis and Fusobacterium nucleatum strains into the right gingival sulcus to analyze the effect of HSGD on the incidence and progression of periodontitis. The alveolar bone heights (ABH) was measured with microcomputed tomography imaging of the HSGD- and general diet (GD)-treated groups. The right ABH was significantly decreased compared to the left in both groups at 4 weeks after induction of inflammation; however, no significant difference was noted between the groups. Notably, the ABH in the HSGD-treated group was significantly decreased at 8 weeks after induction of inflammation, whereas in the GD-treated group, an increase in the ABH was observed; a significant difference of the ABH was noted between the two groups (p < 0.05). At 12 weeks, recovery of the alveolar bone was observed in both groups, with no significant differences in ABH between the two groups. These findings indicate that the intake of excessive sodium attenuates the recovery rate of the alveolar bone even after the local infectant is removed. In addition, this study demonstrates the use of HSGD in establishing a new animal model of periodontitis.

본 연구는 고농도 염화칼슘 처리 토양에서 토양개량제인 하이드로볼, 활성탄의 처리와 수크령 식재 유무에 따른 토양침출수 의 화학적 특성과 토양 내 염분 저감 효과에 미치는 영향을 규명하고자 수행하였다. 고농도 제설제처리 염분토양에서 토양개량 제 하이드로볼, 활성탄의 염분 저감 효과 및 수크령의 식재 효과를 알아보기 위하여 2018년 4월부터 10월까지 유리온실에 직경 10 cm, 높이 9 cm의 플라스틱 포트에 수크령을 식재하고 무처리 (Cont.), 하이드로볼 (H), 활성탄 (AC), 수크령식재 (P), 하이드로볼 + 수크령식재 (H + P), 활성탄 + 수크령식재 (AC + P) 총 6개의 처리구로 나누었다. 염화칼슘 (CaCl2) 처리는 10 mg/L 농도의 수용액을 조제하여 2주 간격 1회 200mL씩 분주하였다. 토양침출수 분석은 pH와 EC, 염류계 치환성양이온 (K+, Ca2+, Na+, Mg2+) 함량을 측정하였고, 수크령의 생육은 초장, 엽장, 엽폭, 엽수를 측정한 뒤 실험종료 후 생체중, 건물중, 건물률, T/R률을 조사 분석하였다. 토양침출수 화학성 분석결과, 토양산도는 처리구별 뚜렷한 차이를 보이지는 않았으나 모든 처리구에서 약산성을 띄었으며, 전기전도도는 H + P, P, AC + P, H, AC, Cont. 순으로 감소하는 경향을 보였다. 염류계 치환성양이온함량에 있어서 토양 염류도의 지표라 할 수 있는 Ca2+ 항목에서 Cont., P, H, AC, H + P, AC + P 순으로 높아지는 경향을 보였다. 수크령의 생육변화는 H + P, AC + P, P 순으로 초장, 엽장, 엽폭, 엽수 모든 항목에서 상대생장률이 통계적으로 유의하게 높게 나타났다. 따라서 하이드로볼과 활성탄은 제설제 피해지역 토양개량제로 활용가치가 높으며 수크령은 토양 내 고농도 염화칼슘 염분저감 식물소재로 적합한 수종이라 판단된다.

본 연구는 L-alanine을 적용한 스크러버의 주류공장 내 CO2 제거효율, 모니터링 데이터 분석/ 평가 및 에너지 저감효율을 평가하였다. 스크러버의 평균 제거율은 90.45%로 10,000 ppm이상의 고농도 CO2가 유입됨에도 제거효율이 뛰어난 것을 확인하였다. 스크러버 작동 후 작업장 내 CO2는 2,000ppm 이 하로 유지하여 약 74% 이상의 이산화탄소 저감 효율을 확인하였다. 또한 소비되는 전력량을 측정한 결과 스크러버 작동 후 230 kWh로 약 7.26%의 에너지가 절감되는 것으로 나타났다. 즉, 본 개발제품을 적용한 결과로 작업장 내 이산화탄소 농도를 외기유입 없이 낮은 농도로 유지함에 따라 근무자의 작업환경을 개선 시킬 수 있었으며 에너지 소비량 또한 저감할 수 있었다. 그러므로 식품, 주류공장 내 고농도 CO2 제거 공 정으로써 스크러버가 유용할 것으로 기대된다.

The high-temperature stability of YSZ specimens fabricated by die pressure and cold isostatic press (CIP) is investigated in CaCl2-CaF2-CaO molten salt at 1,150 °C. The experimental results are as follows: green density 46.7 % and 50.9 %; sintering density 93.3 % and 99.3 % for die press and CIP, respectively. YSZ foremd by CIP exhibits higher stability than YSZ formed by die press due to denseness dependency after high-temperature stability test. YSZ shows peaks mainly attributed to CaZrO3, with a small t-ZrO2 peak, unlike the high-intensity tetragonal-ZrO2 (t-ZrO2) peak observed for the asreceived specimen. The t-ZrO2 phase of YSZ is likely stabilized by Y2O3, and the leaching of Y2O3 results in phase transformation from t-ZrO2 to m-ZrO2. CaZrO3 likely forms from the reaction between CaO and m-ZrO2. As the exposure time increases, more CaZrO3 is observed in the internal region of YSZ, which could be attributed to the inward diffusion of molten salt and outward diffusion of the stabilizer (Y2O3) through the pores. This results in greater susceptibility to phase transformation and CaZrO3 formation. To use SOM anodes for the electroreduction of various metals, YSZ stability must be improved by adjusting the high-density in the forming process.

High surface carbon aerogels with hierarchical and tunable pore structure were prepared using ionic liquid as carbon precursor via a simple salt templating method. The as-prepared carbon aerogels were characterized by nitrogen sorption measurement and scanning electron microscopy. Through instant visual observation experiments, it was found that salt eutectics not only serve as solvents, porogens, and templates, but also play an important role of foaming agents in the preparation of carbon aerogels. When the pyrolyzing temperature rises from 800 to 1000°C, the higher temperature deepens the carbonization reaction further to form a nanoporous interconnected fractal structure and increase the contribution of super-micropores and small mesopores and improve the specific surface area and pore volume, while having few effects on the macropores. As the mass ratio of ionic liquid to salt eutectics drops from 55% to 15%, that is, the content of salt eutectics increases, the salt eutectics gradually aggregate from ion pairs, to clusters with minimal free energy, and finally to a continuous salt phase, leading to the formation of micropores, uniform mesopores, and macropores, respectively; these processes cause BET specific surface area initially to increase but subsequently to decrease. With the mass ratio of ionic liquids to salts at 35% and carbonization temperature at 900°C, the specific surface area of the resultant carbon aerogels reached 2309 m2 g–1. By controlling the carbonization temperature and mass ratio of the raw materials, the hierarchically porous architecture of carbon aerogels can be tuned; this advantage will promote their use in the fields of electrodes and adsorption.

Development of forward osmosis (FO) membranes with high salt selectivity is a essential issue to realize the FO technology. To improve salt selectivity of the FO membrane, a polyamide thin film composite FO membrane was fabricated by the interfacial polymerization method using aromatic hydrocarbon organic solvents on polyacrylonitrile (PAN) supports. The aromatic hydrocarbon organic solvent accelerated amine diffusion rate toward the organic phase and the subsequent reaction, which can improve membrane performance by fabricating a thin and highly dense basal PA layer. As a result, the prepared FO membrane showed ~1.7 times higher flux and ~4.5 times higher salt selectivity compared to HTI-CTA commercial membrane with 1.0 M NaCl draw solution and DI water feed solution in FO mode.

본 연구에서는 고염/고방사성 폐액 내 함유된 주요 고방사성핵종인 Cs 제거를 목적으로 고효율의 복합 흡착제(potassium cobalt ferrocyanide (PCFC)-loaded chabazite (CHA)) 합성 및 이의 적용성을 평가하였다. 복합 흡착제는 Cs을 비롯한 다 른 입자를 수용할 수 있는 CHA를 지지체로 선정하였으며, CoCl2 및 K4Fe(CN)6 용액의 단계적인 함침/침전을 통해 PCFC를 CHA 세공 내에 고정화함으로써 합성하였다. 복합 흡착제의 합성 시 평균 입자크기가 10 ㎛ 이상의 CHA를 지지체로 사용할 경우, PCFC 입자는 안정적인 형태로 고정화되었다. 또한, 합성 시 복합 흡착제의 정제를 증가시키는 세척 방법을 최적화함으로써, 복합 흡착제의 물리적 안정성이 향상되었다. 최적의 합성법을 통해 얻은 복합 흡착제에 의한 Cs 흡착 시, 담수(무염 조건) 및 해수(고염 조건)에서 모두 빠른 흡착 속도를 보였으며, 염 농도와 무관하게 비교적 높은 분배계수 값(104 mL·g-1 이상)을 나타내었다. 그러므로, 본 연구에서 합성한 복합 흡착제는 CHA 및 PCFC가 각각 가지고 있는 물리적 안정성과 Cs 에 높은 선택성 등을 고려하여 촤적화한 소재이며, 고염/고방사성폐액에 함유되어 있는 Cs을 고효율로 신속하게 제거할 수 있음을 알 수 있다.

본 연구에서는 염 농도에 따른 된장의 발효과정 중에microflora와 향미의 변화를 분석하였다. 염 농도가 4.8%,8.4%인 저염 된장의 총균수와 균총의 패턴은 염 농도가12.0%, 15.6%, 19.2%인 고염 된장과 유사하게 나타났다.호기성균과 호염성균의 경우에는 모든 염도와 전 발효 기간에 7-11log CFU/g의 높은 수준에 수치를 보였다. 호기성 세균과 호염성 세균의 균총을 보았을 때, 저염 된장의 발효초기에는 Bacillus licheniformis와 Bacillus amyloliquefaciens가 많은 비중을 차지하였다. 주요 향기성분들을 중심으로 각시료들의 향미성분에 경향성을 보기 위해 SPME를 이용하여 발효 기간 중 변화량 값을 GC-MS 통해 비교 분석한결과, dehydes, alcohols, acids의 경우 발효 초기부터 발효3개월까지 저염화 시료에서 많이 생성되었으며 발효가 지속적으로 진행됨에 따라 시료들 간의 격차는 점차 감소하였다. 발효 6개월 부터 저염 시료에서도 다양한 pyrazine이 형성되었다.

염 함량을 달리한 된장을 초고압 처리하여 미생물 저감 특성을 조사함으로써 된장, 특히 저염 된장의 저장성을 높이기 위하여 초고압기술의 적용가능성을 검토하였다. 초고압처리에 의한 된장 미생물 사멸효과는 전반적으로 낮은 것으로 나타났으며, 초고압처리에 의한 미생물 사멸효과는 염 함량에 반비례하는 경향을 보였다. 미생물 종류에 따른 초고압사멸효과는 곰팡이, 효모, 세균 순으로 낮아졌다. 염 함량 10% 이하의 저염 된장은 6500 기압에서 40 분간 초고압처리에 의해 곰팡이와 효모가 거의 사멸되었으며, 초고압처리는 저염 된장의 유통기간 향상에 기여할 것으로 기대되었다.

본 연구는 염류집적 국화 재배지 토양적응성 인산분 해미생물 탐색하고 선발된 미생물 시용을 통한 염류집 적 국화 재배지 토양에서의 토양 화학성의 변화를 조 사하였으며 이를 통하여 염류 집적 국화 재배지 토양 환경 개선 기술을 개발하고자 수행되었다. 시험에 사용 된 인산분해미생물은 염류집적토양에서 분리된 Pseudomonas putida(KSJ11), Acinetobacter calcoaceticus (KSJ3) 및 Acinetobacter calcoaceticus (WP20) 3종류 이었으며 미생물의 제형은 버미큘라이트에 혼합되어 있 는 상용화된 제품을 이용하였다. 시험장소는 광주광역 시 광산구 소재 신우화훼농장의 15년간 작물이 재배되 어 염류집적현상이 나타나는 국화재배지에서 처리구 82 m2에 각각의 미생물 제재 250 L씩 시용하였다. 염 류집적이 이루어진 국화재배온실에 처리된 인산분해미 생물 Acinetobacter calcoaceticus(KSJ3; WP20)는 유 효인산을 효율적으로 분해하는 것으로 나타났으며, 특히 Acinetobacter calcoaceticus(WP20)는 염류의 분 해능력이 높았다. 인산분해미생물 시용에 따라 토양내 칼륨, 칼슘 및 마그네슘의 함량의 증가가 A. calcoaceticus(KSJ3; WP20)처리구에서 뚜렷하게 나타났 으며 이러한 변화의 영향으로 판단되는 토양내 전기전 도도도 증가되었다. 또한 인산분해미생물 시용은 선충 밀도의 감소효과를 나타내어 토양환경개선을 위한 재 료로 활용될 가능성을 나타내었다. 결과적으로 염류집 적이 이루어진 국화재배 온실에서의 인산분해미생물 시 용은 처리된 미생물의 종류에 따라 차이를 나타내었지 만 토양의 유효인산량 증가와 양이온의 유용화에는 분 명한 효과를 나타내었다. 따라서 염류집적 토양에서의 인산분해미생물 시용은 토양양분의 효율적인 사용을 가 능하게 할 수 있는 방안이 될 수 있기 때문에 시비량 절감 등의 방법으로 활용할 수 있다고 판단되었다.

This study investigated the effect of vegetation mat on plant growth and salt reduction in the soil treated with high concentration deicing salt. In order to measure soil chemical characteristics and plant growth, three native groundcover plants (Dendranthema zawadskii var. latilobum, Dendranthema boreale, and Kalimeris yomena) were grown in each of the three plastic containers (50.0 cm width × 35.0 cm length × 8.5 cm deep) with a high concentration treatment of calcium chloride deicing salt. There were two treatments: control, and BVM that combines B (blanket) and VM (vegetation mat). 1,600 g of soil was placed on the top of the drainage layer with 290 g of perlite, 100 seeds each of the three native plants with three repetitions were sowed, and 10 g/L of calcium chloride deicing salt was added in the treatment. As a result of the chemical properties of soil, soil in control treatment was acidic and soil electrical conductivity in BVM was the lowest. Also, exchangeable cations (K+, Ca2+, Na+, and Mg2+) in soil and all the three plants were significantly decreased in the BVM treatment. Meanwhile, the germination rate of Dendranthema zawadskii var. latilobum was the highest under high concentration deicing salt in compared to the two plants. Overall, three native groundcover plant growth was higher in the BVM than control treatment significantly. These results suggest that the treatment of blanket vegetation mat has a positive effect on soil and plant growth in soil damaged by deicing salt.