• Korean Chemical Engineering Research
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• 제58권3호
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• pp.474-479
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• 2020

유리기판의 박막화를 위한 식각액을 제조하였고, 습식 식각액의 주성분으로 HF를 사용하였다. HF를 기본으로 한 식각액에 HCl, HNO₃, H₂SO₄와 같은 강산과 구연산과 같은 카르복실산 그리고 여러 종류의 아미노산을 첨가물로 각각 사용한 식각액으로 유리의 식각속도와 표면형상의 변화를 측정하였다. 강산의 종류와 상관없이 첨가량이 증가함에 따라 선형적으로 유리의 식각속도가 증가하였으며 유리표면의 슬러지 제거효과도 나타내었다. HCl이 함유된 식각액이 식각속도의 증가율과 슬러지 제거 효과에서 다른 강산보다 효율적인 결과를 보였다. 카르복실산의 첨가는 식각속도에 영향을 크게 주지 않으나 슬러지 제거효과를 보였다. 하지만 아미노산을 첨가한 경우에는 식각속도의 변화와 슬러지 제거 효과가 크지 않았다.

• Fisheries and Aquatic Sciences
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• 제25권4호
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• pp.189-201
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• 2022

Jellyfish is an emerging aquaculture species, farmed for Oriental cuisines and nutraceutical ingredients. This study aimed to examine antioxidative and antimicrobial potentials of various fractions of the jellyfish, Acromitus hardenbergi. The bell and oral arms of the jellyfish were sequentially extracted with petroleum ether (PE), dichloromethane (DCM), chloroform (CHCl₃), methanol (MeOH), and water (H₂O) to extract its bioactive in an increasing polarity gradient. Test fractions were assayed for antiradical activities using electron spin resonance spectrometry, β-carotene-linoleate model and Folin-Ciocalteu assay; and antimicrobial activity against 2 Gram-negative bacteria, 4 Gram-positive bacteria and 2 fungal species using the disc diffusion assay. All fractions were also subjected to Fourier Transform Infrared (FTIR) analysis to identify types of functional groups present. It was found that the hydrophilic extracts (H₂O fractions) possessed the most effective radical scavenging activity (p < 0.05) while the lipophilic extracts (PE fractions) the most active antimicrobial activity, especially against Gram-positive bacteria (p < 0.05). Total oxidation substrates content was found to be highest in the PE fractions of jellyfish bell and oral arms (p < 0.05). FTIR data showed that the H₂O and MeOH fractions contains similar functional groups including -OH, -C=O, -N-H and -S=O groups, while the PE, DCM, and CHCl₃ fractions, the -CH₃, -COOH groups. This study showed that A. hardenbergi contains antioxidants and antimicrobials, thereby supporting the traditional claim of the jellyfish as an anti-aging and health-promoting functional food. Bioassay-guided fractionation approach serves as a critical milestone for the strategic screening, purification, and elucidation of therapeutically significant actives from jellyfish.

• Journal of Electrochemical Science and Technology
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• 제14권3호
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• pp.262-271
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• 2023

For electrode stability and the electrochemical performance of the Li-ion cell, it is essential that the active ingredients and unique additives in the polymer binder be well dispersed with the solvent-based slurry. The efficient procedure used to create the slurry affects the rheological characteristics of the electrode slurry. When successively adding different steps of Nmethyl-2-pyrrolidone (NMP) solvent to the cathode composition, it is evenly disseminated. The electrochemical performance of the Li-ion cells and the electrodes made with slurry formed by single step and multiple steps of addition of NMP solvent are examined. To preform rheological properties of cathode electrode slurry on Ni-rich Lithium Nickel-Cobalt-Aluminum Oxide (LiNi_0.80Co_0.15Al_0.05) (NCA). Also, we investigate different step addition of electrode formation and mechanical strength characterization like peel strength. According to the EIS study, a multi-step electrode slurry has lower internal resistance than a single-step electrode slurry, which results in better electrical characteristics and efficiency. Further, microstructure of electrodes is obtained electrochemical performance in the 18650 cylindrical cells with targeted capacity of 1.5 Ah. The slurry of electrodes prepared by single step and multiple steps of addition of NMP solvent and its effect on the fabrication of 1.5 Ah cells. A three-step solvent addition on slurry has been found to be a lower internal resistance than a single-step electrode slurry as confirmed by the EIS analysis, yielding improved electrical properties and efficiency.

• 대한화장품학회지
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• 제38권1호
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• pp.43-50
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• 2012

인체피부에서 화장품이나 화장품 원료의 안전성시험은 대체로 육안평가로 이루어져왔다. 하지만, 피부반응 초기의 미세한 변화에 대해서 육안으로는 감지하지 못하는 경우가 많다. 따라서, 본 연구에서는 수종의 화장품 원료에 의해 유발되는 홍반반응에 대해 육안평가뿐 아니라, 레이저도플러혈류이미지(LDPI) 측정장비를 이용한 혈류변화 측정, $Vapometer^{(R)}$를 이용한 경피수분손실량(TEWL) 측정, 분광광도계를 이용한 피부색 측정과 같은 기기평가를 병행하여 비교하였다. 30명의 건강한 여성 피험자를 대상으로 오일류 7종, 계면활성제류 6종, 보습제류 5종을 피험자의 등 부위에24 h 폐쇄첩포(D0)하여 피부반응을 유도하였고 첩포 제거 후 30 min (D1), 24 h (D2)에 육안평가와 기기평가를 각각 실시하였다. 육안평가 결과, 프로필렌글라이콜을 제외한 모든 오일류와 보습제류는 저자극 수준의 피부반응(반응도 0+ - 2.9+)을 보인 반면, 프로필렌글라이콜과 모든 계면활성제류는 중자극에서 강자극 수준의 피부반응(반응도 3+ - 5+)을 보였다. 기기측정 결과, 육안평가에서 저자극 범주의 피부반응에 대해서 혈류량이나 피부색보다 경피수분손실량이 가장 민감하게 피부변화를 감지하였다.

• 동아시아식생활학회지
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• 제4권3호
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• pp.147-169
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• 1994

This study was conducted to ivestigate the quality of modeled chinese-cabbage Kimchi. The mutual action of sub-ingredients and optimum mixing conditions were examined by analyses of pH, acidity, content of vitamins, carotenes, number of total microorganism, and Lactobacilli, the activities of softening related to enzymes (polygalacturonase and ${\beta}$-galactosidase), and sensory quality during fermentation. The result about the mutual action of red pepler powder and garlic showed that the pH was decresed as concentration of garlic was higher and that of red peppler powder became lower. Kimchi had unpleasant taste and undesirable odor when the adding ratio of the peper powder and garlic was unbalanced. As the concentration of garlic became higher, the content of vitamin C in Kimchi tissue decreased while that of vitamin C in Kimchi juice increased. The contents of vitamin B1, B2 and carotene increased as the concentration of garlic became lower. The optimum mixing ratio of red pepper powder and garlic evaluated by overall eating quality was 4.66% and 3.45%, respectively. The result about the mutual action of ginger and green onion was that pH became higher as the concentration of ginger was 1.84% and that of green onion was 5.96%. The intensity of fresh taste and odor became stronger as the concentration of ginger increaed to 2.76% and that of green onion decreased to 2.98%. The balance of sour, salty and hot taste became better as the concentration of ginger increased and that of green onion decreased. The optimum mixing condition evaluated by overall eating quality was 2.94% in ginger ＋ 2.78% in green onion. The contents of vitamin B1, B2 and C were high in this condition. The result about the mutual action of leek and salted anchovy juice was that pH became lower as the concentration of leek increased and that of salted anchovy juice decreased. Sour, hot and sweet tastes were good in the condition of leek 12%, salted anchovy juice 4.69%. Palatable, fresh taste and odor became weaker when the one of both sub-ingredients was too much little. The optimum mixing condition evaluated by overall easting quality was 9.76% in leek ＋ 7.32% in salted anchovy juice. The contents of vitamin B1, B2, C and carotene were high in this condition and other sensory qualities were good. The result about the mutual action of salt and sugar was that pH became lower as the concentration of sugar became higher and that of salt became lower. The sweet taste was reduced of hot taste than salty taste. Palatable and fresh tastes were desirable when Kimchi fermented with less salt and more sugar. The optimum mixing condition evaluated by overall eating quality was 3.29% in sugar ＋ 4.80% in salt. The contents of vitamin B1, B1, C and carotene were high in this condition. The result of model Kimchi fermented at 20$^{\circ}C$ was that the number of Lactobacilli in model Kimchi was higher than that of in control Kimchi. The fermentation period was extended under pH 4.0 and the contents of vitamin B1, B1,C and carotene were high through the whole edible period. The activity of polygalacturonase was low, but that of ${\beta}$-galactosidase was high during fermentation.

• 한국식품저장유통학회지
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• 제4권2호
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• pp.215-225
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• 1997

The review was conducted to organize the desirable salting process from the literatures. In this study the principle of salting and effects of physicochemical changes in salting and salting factors such as cultivars of baechu(Chinese cabbage), concentration of salt, salting temperature, pH condition for salting and quality of kimchi were studied. The method of salting standard, treatment techniques in salting, and selection and mixture ratio of sub-ingredients were also reviewed. In future studies greater attention should be paid to salting and fermentation of kimchi.

• 동아시아식생활학회지
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• 제4권2호
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• pp.75-91
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• 1994

As a part of the fermentation control scheme for the preservation and improvement of the quality of Kimch, this paper summerizes a result of the research into the cleaning method of materials, the fermentation of Kimch using cleaning materials, the search of lacticacidbacteria for starter, the seperation state of cell wall by starter, the fermentation of Kimchi in the airtight instrument and in the air controlled state. And it shows the influence on the growth of lacticacidbacteria when the herb-medicine is used as a sub-ingredients, and the effects on the quality of ginseng added Kimchi.

• 전자통신동향분석
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• 제36권3호
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• pp.76-86
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• 2021

Technologies for lithium secondary batteries are now increasingly expanding to simultaneously improve the safety and higher energy and power densities of large-scale battery systems, such as electric vehicles and smart-grid energy storage systems. Next-generation lithium batteries, such as lithium-sulfur (Li-S) and lithium-air (Li-O₂) batteries by adopting solid electrolytes and lithium metal anode, can be a solution for the requirements. In this analysis of battery technology trends, solid electrolytes, including polymer (organic), inorganic (oxides and sulfides), and their hybrid (composite) are focused to describe the electrochemical performance achievable by adopting optimal components and discussing the interfacial behaviors that occurred by the contact of different ingredients for safe and high-energy lithium secondary battery systems. As next-generation rechargeable lithium batteries, Li-S and Li-O₂ battery systems are briefly discussed coupling with the possible use of solid electrolytes. In addition, Electronics and Telecommunications Research Institutes achievements in the field of solid electrolytes for lithium rechargeable batteries are finally introduced.

• 한국수산과학회지
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• 제56권4호
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• pp.526-531
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• 2023

This study investigated the ingredients, anti-aging and anti-dementia activities of the Korean marine algae Silvetia siliquosa. The S. siliquosa solvent extracts were prepared with 70% ethanol, 80% methanol, and distilled water. The extraction yield range of various solvent extracts was 15.82-49.98%. The ethanol and methanol extracts had higher tyrosinase and collagenase inhibitory activities than those of the water extract. Meanwhile, all extracts exhibited high elastase inhibitory activity. Conversely, the methanol and water extracts exhibited the highest acetylcholinesterase inhibitory activity (IC₅₀, 0.40 mg/mL) and β-secretase inhibitory activity (IC₅₀, 0.81 ㎍/mL), respectively. These results indicate that S. siliquosa may be useful in food and pharmaceutical materials as a cosmetic and functional.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.332-332
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• 2022

Ginseng has been traditionally used in Asia including Korea, for health care and to treat verities of different diseases such as immune disease, liver disease, and cancer. The current study was aim to unveal the most efficient method such heating, prethanol-A and ultrasound, for cured extraction of ginseng with higher antioxidant activity. The current results shows a significant improvement in the inhibition of H₂O₂ by the ultrasound method than the HT and Pre-A method. Thus this inhibition in free redical is possible through the increase in the antioxidant activity. Therefore in this study the CAT, APX and phenolic and flavonoid content was increased in ginseng seed and germinated ginseng sprouts by the US method, while the POD, SOD and GSH activity was increased in HT method. This suggest that the different extraction method in different stage of ginseng growth show a different biochemical and metabolites activation. Thereby the Ultrasound and Heat extraction was a feasible alternative method for extracting interested ingredients from biological materials.