• Journal of Food Hygiene and Safety
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• v.38 no.4
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• pp.273-278
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• 2023

This study aimed to predict the shelf life of black soybean Sunsik to develop a functional labeling system for the product. The Arrhenius equation was used to calculate the shelf life by examining alterations in the dietary fiber and calcium levels of black soybean Sunsik stored at 25, 35, and 50℃ for 0, 6, and 12 months. Dietary fiber and calcium analyses were performed according to the experimental methods specified in the Food Code of the Ministry of Food and Drug Safety. Both black soybean Sunsik (BS) and black soybean Sunsik containing nondigestible maltodextrin and calcium lactate (BSN) exhibited an upward trend in dietary fiber content after 12 months of storage, compared to their initial levels. During storage, the phytate in Sunsik degraded, releasing cations that facilitated the formation of new cross-links between pectic acid and middle lamella, which ultimately increased dietary fiber content. Conversely, the calcium contents of both BS and BSN decreased with prolonged storage. Based on these findings, the expected shelf life of BS and BSN was calculated as 15.65 and 28.34 months, respectively.

• Clean Technology
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• v.16 no.4
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• pp.284-291
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• 2010

Nitrous oxide ($N_2O$) is a greenhouse material which is hard to remove. Even with a catalytic process it requires a reaction temperature, at least, higher than 670 K. This study has been performed to see the effects of Ce addition to the mixed oxide catalyst which shows the highest activity in decomposing $N_2O$ completely at temperature as low as 473 K when CO is used as a reducing agent. Mixed metal oxide(MMO) catalyst was made through co-precipitation process with small amount of Ce added to the base components of Co, Al and Rh or Pd. Consequently, the surface area of the catalyst decreased with the contents of Ce, and the catalytic activity of direct decomposition of $N_2O$ also decreased. However, in the presence of CO, the activity was found high enough to compensate the portion of activity decrease by Ce addition, so that it can be ascertained that the catalytic activity and stability can be maintained in the CO involved $N_2O$ reduction system when Ce is added for the physical stability of the catalyst.

• Nuclear Engineering and Technology
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• v.11 no.3
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• pp.203-212
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• 1979

The thermal decomposition of simulated Magnox highly active waste and of HARVEST feed slurries (SW and SG) which include tile glass forming chemicals has been studied. The waste and the slurries are almost completely calcined by 500-55$0^{\circ}C$. The colour of the solids from the slurries varies little until about 90$0^{\circ}C$ when it darkens considerably. The slurries begin to vitrify at this temperature and are completely vitrified at 1000-105$0^{\circ}C$. On the other hand. the sulphate impurity in SN slurry causes a yellow phase to separate above 75$0^{\circ}C$. The density of the intermediate solids is fairly low until 650$^{\circ}$-$700^{\circ}C$ is reached. This temperature seems to mark the onset of fluxing as tile density rises quickly to 2g/㎤ at 700$^{\circ}$ -80$0^{\circ}C$. The strengh of the solids decreases with temperature up to 50$0^{\circ}C$, and then rises as the solids begin to sinter. Below 50$0^{\circ}C$ the SN solids are the stronger. suggesting that the impurity renders this silica more reactive.

• Clean Technology
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• v.29 no.2
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• pp.102-108
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• 2023

This study applied a hydrothermal carbonization (HTC) method to carbonize sewage sludge in order to satisfy the criteria of the Waste Management Act for recycled products and to explore the possibility of recycling sludge into modification blocks. Cement was mixed with carbonized sludge generated at the optimal temperature and reaction time during HTC. After that, the compressive strengths of the modification blocks were measured by conducting both a performance and leaching test. The results of the leaching test showed that heavy metals were not detected, and the specific gravity and absorption rates were less than 1.7 and 10%, respectively, indicating that all species satisfied the criteria. The results of the compressive strength test showed that a mixing ratio of 5% and 7% with cement cured for 28 days satisfied the criteria of A, B, and C type blocks but a mixing ratio of 3% with cement did not satisfy the criteria of A type blocks after 28 days. However, after additional curing for 42 days, the mixing ratio of 3% also satisfied the A type block criteria. Therefore, the optimal mixing ratio of carbonized sludge and cement was considered to be between 3% and 5% and confirmed that the modified blocks could be utilized as aggregates.

• The Journal of Engineering Geology
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• v.33 no.2
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• pp.257-273
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• 2023

Hydrochemical characteristics and microbial communities of spring (Samtong), surface water, and groundwater in Cheorwon, Korea, were analyzed. Field surveys and water quality analyses were undertaken at 10 sampling points for five spring, two surface, and three groundwater samples on 15 December 2022. Hydrochemical analysis revealed that most water samples were Ca-HCO₃ type and that water-rock interactions were the predominant mineral source. Radon concentrations were <1 kBq m^-3 for surface water, 1~10 kBq m^-3 for spring water, and 1~1,000 kq m^-3 for groundwater. Microbial cluster analysis showed that the main phyla were Proteobacteria, Planctomyceta, Verrucomicrobia, Acidobacteria, and Actinomycetota.Non-metric multidimensional scaling (NMDS) analysis indicated that water temperature, pH, and Si content were closely related to microorganism content. NMDS and canonical correspondence analysis results revealed that environmental factors affecting spring water were temperature, and Mg and Si concentrations, particularly for Acidobacteria and Proteobacteria, and Pseudomonas brenneri. Both hydrochemical and microbial community analyses yielded similar results at some spring and groundwater sampling points, likely due to the effects of a basalt aquifer.

• Analytical Science and Technology
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• v.21 no.2
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• pp.123-128
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• 2008

The golden turbid solution of cordierite precursor was obtained by using magnesium ethoxide in sol-gel method, while the clear solution of cordierite precursor was obtained when 5%-$Zr(OC_3H_7)_4$ solution was used in the sol-gel reaction. $SiO_2$ component was confirmed by infrared spectra showing $1045cm^{-1}$ and the stretching vibration of gelish $SiO_4$ showed $1140cm^{-1}$ and $940cm^{-1}$. The component of $Al_2O_3$ showed at $580cm^{-1}$ and network structure of $Al_2O_6$ showed at $680cm^{-1}$. The component of MgO was confirmed at $575cm^{-1}$ as the stretching vibration. X-ray diffraction analysis showed ${\mu}$-cordierite crystal was showed up at temperature above $1000^{\circ}C$ at the mole ratio of cordierite precursor and water (1:5). ${\mu}$-Cordierite and ${\alpha}$-cordierite were coexisted at $1050^{\circ}C$ for the mole ratio of cordierite precursor and ammonia (1:5) while ${\alpha}$-cordierite was only existed at $1100^{\circ}C$ for the same mole ratio as mentioned above.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.84-84
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• 2020

염증 (Inflammation)은 병원체, 손상된 세포, 자극물질 등으로 인한 손상에 대해 작용하여 조직이나 장기의 손상을 재생하는 작용으로써 신체 방어 기전들 가운데 매우 중요한 역할을 하는 것으로 알려져 있다. 이러한 염증반응이 과다할 경우 각종 염증성 질환 혹은 암 등을 유발하는 원인으로 발전할 수 있어 항염증제의 개발은 전 세계적으로 중요시되고 있다. 선천적 면역을 담당하는 대식세포는 lipopolysaccharide(LPS), 활성산소 (ROS) 등에 의해 자극되어 염증인자 생성에 관여한다. 따라서 본 연구에서는 항염증 소재 개발을 목표로 하며, 국내 천연소재를 활용한 기능성 항염증 소재로 전북 순창군에서 재배된 초석잠(Stachys Sieboldii MIQ.)과 돼지감자 (Helianthus tuberosus L.)를 이용하여 항산화 활성을 평가하고자 하였으며, 대식세포주를 활용한 세포독성 및 항염증 활성에 대한 효능을 확인하고자 하였다. 본 연구는, 전북 순창 지역에서 재배 된 초석잠과 돼지감자를 사용하여 각 조건의 추출 용매, 온도, 시간별 추출물의 Total polyphenol 함량 평가를 통한 최적 추출조건 선정을 진행하고, 선정된 추출조건의 추출물의 항산화 활성을 측정하기 위해 DPPH & ABTS radical scavenging activity 분석 및 Total flavonoids 함량 분석을 통해 항산화 효능 평가를 진행하였다. 또한 항염증 소재로의 활용을 위해 대식세포인 Raw 264.7을 사용하여 농도별 MTT assay를 진행하여 세포독성 평가를 진행하였고, Nitric oxide (NO) 생성억제 효능을 확인하여 항염증 활성을 평가하였다. 실험 결과, Total polyphenol 함량 분석을 통해 최적 추출조건이 선정된 초석잠 (25℃, 주정 60%, 3 h), 돼지감자 (25℃, 주정 40%, 1 h)은 최적 조건에서 약 58 mg GAE/g 및 158 mg GAE/g의 총 폴리페놀 함량을 보였으며, DPPH & ABTS radical scavenging activity 및 Total flavonoids 함량 분석한 결과, 초석잠이 돼지감자보다 더 높은 항산화 활성을 나타내었다. 대식세포 실험에서의 추출물 처리군의 세포독성 측정 결과, 100 ug/mL 이내의 농도에서 독성활성이 나타나지 않음을 확인하였고, Nitric oxide (NO) 생성 억제활성 측정을 통해 LPS 처리군 대비 접종량 100 ug/mL 기준 각각 초석잠 약 47%, 돼지감자 약 49% 수준의 항염증 활성을 확인하였다.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1225-1234
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• 2023

The intensity of crop water stress caused by moisture deficit is affected by growth and heat conditions. For more accurate detection of crop water stress state using remote sensing techniques, it is necessary to select vegetation indices sensitive to crop response and to understand their changes considering not only soil moisture deficit but also heat conditions. In this study, we measured the MERIS terrestrial chlorophyll index (MTCI) and chlorophyll/carotenoid index (CCI) under drought and heat wave conditions. The MTCI, sensitive to chlorophyll concentration, sensitively decreased on non-irrigation conditions and the degree was larger with heat waves. On the other hand, the CCI, correlated with photosynthesis efficiency, showed less sensitivity to water deficit but had decreased significantly with heat waves. After re-irrigation, the MTCI was increased than before damage and CCI became more sensitive to heat stress. These results are expected to contribute to evaluating the intensity of crop water stress through remote sensing techniques.

• Food Science and Preservation
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• v.30 no.1
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• pp.122-131
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• 2023

Persimmon peels are mostly discared as a by-product of dried persimmon manufacturing, but effective use is required as it contains various functional constituents. This study covers the preparation of carotenoid-enriched oil by ultrasound treatment of persimmon peel in soybean oil solvent, and the investigation of its physicochemical characteristics. Using the Box-Behnken design and response surface methodology, the optimal extraction conditions (temperature, 62℃; time, 32 min; and persimmon peel to oil ratio, 1:3.1) were determined based on the carotenoid concentration of the extract. The physicochemical characteristics of the extract obtained under optimal conditions and the untreated soybean oil (control) were compared. The total carotenoid content of the extract increased. The carotenoid-enriched soybean oils had a lighter color than the controls, but with high redness and yellowness values. The effect of sonication and a component of the persimmon peel on the oxidation and heating stability of soybean oil was weak. The viscosity and activation energy of carotenoid-enriched soybean oil were slightly higher than those of the control. Thus, it was possible to prepare yellow-red carotenoid-enriched soybean oil by applying ultrasonic-soybean oil solvent extraction to persimmon peel. The oil is expected to be useful as an additive as well as a substitute for general edible oils.

• Resources Recycling
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• v.33 no.3
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• pp.30-37
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• 2024

In this study, we investigated the separability of vanadium and tungsten from spent SCR (Selective Catalytic Reduction) catalyst leach solution by reduction of vanadium and solvent extraction using Alamine 336 and conducted experiments to optimize process conditions. It is difficult to separate vanadium and tungsten due to their similar chemical behavior, but tungsten can be selectively extracted from acidic solution when vanadium extraction is prevented by reducing anionic pentavalent vanadium to cationic tetravalent vanadium. The results showed that NaHSO₃ was most suitable as a reducing agent, and the extraction efficiency of vanadium decreased and the separation efficiency increased as the amount of reducing agent added, reaction time, and temperature increased. When reducing NaHSO₃ 1.5 eq, 60 min, and 60℃, which are optimal conditions of reduction, vanadium and tungsten were effectively separated with vanadium extraction efficiency of 5.8%, tungsten extraction efficiency of 99%, and separation factor of vanadium and tungsten of 7,564.