• 제목/요약/키워드: biological stability

검색결과 838건 처리시간 0.03초

플라즈마 화장품 용기 적합성 (Plasma Cosmetic Container Suitability)

  • 조하현;천유연;허효진;이상훈;;김예지;곽병문;이미기;빈범호
    • 대한화장품학회지
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    • 제50권1호
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    • pp.59-65
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    • 2024
  • 플라즈마 화장품은, 플라즈마의 제형 내 장기 안정성을 확보하는 것이 중요하다. 이번 연구는 효율적인 플라즈마 화장품 개발을 위하여 용기 적합성을 검토하였다. 플라즈마가 닿는 표면적을 달리하여, 4 cm2, 25 cm2, 75 cm2, 175 cm2 용기 별로 화장품 제조용 플라즈마를 주입 후, 질소 플라즈마 주요 활성 종인 nitric oxide (NO)의 양을 추적 분석 하였다. 그 결과, 플라즈마에 노출된 표면적과 안정도는 반비례 경향을 나타내었고, 4 cm2 용기에서 가장 효과적이었다. 추가적으로, 25 mm, 40 mm, 50 mm 바이알 병에 플라즈마를 처리하였고, 그 결과 공기에 노출된 용기의 표면 면적이 작은 25 mm에서 NO의 상대적 장기 안정성이 확보되었다. 화장품 제형으로 수상 미스트(water mist)와 층 분리 미스트(stratified mist)를 선택하여 수상층 부분에 NO 플라즈마를 주입 후 제형의 성상 및 주입한 NO 플라즈마의 상태 변화를 관찰하였다. 두 제형에서 NO 플라즈마의 주입량은 수상 미스트가 층 분리 미스트보다 약 1.5 배 가량 높았으며, 층 분리 미스트는 시간에 따라 점차 감소하여 3 주 후, 소실되는 것이 확인되었다. 저온(4 ℃), 실온(25 ℃), 고온(37 ℃, 50 ℃)에서 질소 플라즈마의 안정도를 진행하였다. 그 결과 수상 미스트는 안정도에 영향을 미치지 않는 것을 확인하였지만, 층 분리 미스트는 유상층에서 색 변화를 관찰하였다. 종합적으로, 본 연구는 질소 플라즈마의 용기 적합성을 제시하고 있으며 화장품 제형 내 주입된 질소 플라즈마의 안정성 확보의 중요성을 시사하고 있다.

효소에 의한 제탁조작과 맥주의 발포성 제I보. 제조공정중의 발포성상실 (Enzymatic Chillproofing and Beer Foam Stability- Part 1. Foam Deterioration during Manufacturing Processes)

  • Pack, M.Y.
    • 한국미생물·생명공학회지
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    • 제3권2호
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    • pp.83-87
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    • 1975
  • 발효직후의 처여맥관가 갖인 우수한 발포성이 제조공정이 끝날 무렵에는 현저히 손실되는 사실을 발견하고 그 원인을 조사한 결과 효소에 의한 제탁조작을 동반한 숙성 및 멸균과정이 맥주의 발포성을 크게 상실시킨다는 것이 증명되었다.

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Human $\alpha_1$-Antitrypsin Variant with Enhanced Conformational Stability at the Cost of Activity

  • Seo, Eun-Joo;Hana Im;Yu, Myeong-Hee
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1997년도 학술발표회
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    • pp.39-39
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    • 1997
  • Native strain of inhibitory SERPINS (Serine protease inhibitors) is thought to be used in the facile conformational switch to play biological regulation. Many heat stable variants of $\alpha$$_1$-antitrypsin, a prototype of inhibitory serpins, increased their stability by reducing the native strain.(omitted)

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Stability of the current biological drugs(typhoid vaccine)

  • Lee, Joo-Hyeun;Ham, Myung-Hwa;Lim, So-Hee;Lee, Gil-Woong
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.328.2-328.2
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    • 2002
  • This paper presents stability of tyhoid vaccine -attenuuated vaccine(oral) and killed vaccine{vi polysaccharide)- 5 classes with various temperature(3 points: iced temperature, refrigeration temp.. indoor temp.). Analytical techniques -vi polysaccharide content. pH. sterility. assay - have been used for the quantity of pharmacologically active chemical entries. From this study. we have found the attenuated vaccine is show iced temp. 258% and indoor temp. 0.02% compare with refrigeration temp. in assay examination and the killed vaccine is not found different. (omitted)

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Urokinase Conjugated with Water-Soluble Dextran

  • 김남득;김현표;변시명;김성완
    • Bulletin of the Korean Chemical Society
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    • 제6권4호
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    • pp.210-214
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    • 1985
  • Urokinase, a plasminogen activator, was conjugated with dextran by the cyanogen bromide activation-coupling method. The resulting water-soluble conjugate was purified by gel permeation chromatography on Sephadex G-200. The maximal activity was obtained when the ratio of urokinase/dextran was 1/20 for the coupling. The final preparation showed 5 CTA units/mg conjugate, 300 CTA units/mg protein, 8.4 % activity retention, and 47 % protein retention. The urokinase-dextran conjugate had good thermal, pH and storage stabilities. In addition, it showed greater resistance to the inhibitory effect of human plasma than native urokinase. Also in vitro biological half-life of urokinase increased 40 times by this conjugation. In view of activity, excellent stability and increased half-life, the conjugate can be a potential fibrinolytic agent in an injectable form.

하천수 내 생물학적 안정성에 따른 유기물 특성변화와 오존산화기반 전처리 연구 (Biological stability in the ozone and peroxone pretreatment systems in river water)

  • 박세희;노진형;박지원;맹승규
    • 상하수도학회지
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    • 제32권2호
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    • pp.159-168
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    • 2018
  • Climate change is believed to increase the amount of dissolved organic matter in surface water, as a result of the release of bulk organic matter, which make difficult to achieve a high quality of drinking water via conventional water treatment techniques. Therefore, the natural water treatment techniques, such as managed aquifer recharge (MAR), can be proposed as a alternative method to improve water quality greatly. Removal of bulk organic matter using managed aquifer recharge system is mainly achieved by biodegradation. Biodegradable dissolved organic carbon (BDOC) and assimilable organic carbon (AOC) can be used as water quality indicators for biological stability of drinking water. In this study, we compared the change of BDOC and AOC with respect to pretreatment methods (i.e., ozone or peroxone). The oxidative pretreatment can transform the recalcitrant organic matter into readily biodegradable one (i.e., BDOC and AOC). We also investigated the differences of organic matter characteristics between BDOC and AOC. We observed the decreases in dissolved organic carbon (DOC) and the tryptophan-like fluorescence intensities. Liquid chromatographic - organic carbon detection (LC-OCD) analysis also showed the reduction of the low molecular weight (LMW) fraction (15% removed, less than 500 Da), which is known to be easily biodegradable, and the biopolymers, high molecular weight fractions (66%). Therefore, BDOC consists of a broad range of organic matter characteristics with respect to molecular weight. In AOC, low molecular weight organic matter and biopolymers fraction was reduced by 11 and 6%, respectively. It confirmed that biodegradation by microorganisms as the main removal mechanism in AOC, while BDOC has biodegradation by microorganism as well as the sorption effects from the sand. $O_3$ and $O_3+H_2O_2$ were compared with respect to biological stability and dissolved organic matter characteristics. BDOC and AOC were determined to be about 1.9 times for $O_3$ and about 1.4 times for $O_3+H_2O_2$. It was confirmed that $O_3$ enhanced the biodegradability by increasing LMW dissolved organic matter.

유기 솔더 보존제의 코팅 및 플럭싱에 대한 메탄올/이소프로필알콜 비율의 영향 (Effect of MeOH/IPA Ratio on Coating and Fluxing of Organic Solderability Preservatives)

  • 이재원;김창현;이효수;허강무;이창수;최호석
    • Korean Chemical Engineering Research
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    • 제46권2호
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    • pp.402-407
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    • 2008
  • 최근 모바일 전자 제품의 많은 사용으로 인하여 전자 기판의 기계적 충격에 대한 기준이 강화되고 있다. 따라서, 전자 기판의 패키징 공정에서 칩과 기판 간의 솔더 볼의 접합방법은 제품의 안정성과 신뢰성 확보를 위하여 기존의 금속간 화합물을 사용하는 방식에서 유기 솔더 보존제를 사용하는 방법으로 전환되고 있다. 그러나 기존의 유기 솔더 보존제들은 공정상에서의 열안정성 등의 여러 가지 단점이 발견되어 이를 보완하기 위한 새로운 유기 솔더 보존제의 개발이 요구되고 있다. 이전 연구에서 새로 개발된 유기 솔더 보존제를 기존 패키징 공정에 적용(플럭싱 공정에 적용)할 때, 사용되는 플럭스의 성분비(메탄올/이소프로필알콜)에 따른 플럭싱의 차이를 파악하고, 이를 통하여 새로운 유기 솔더 보존제에 적합한 플럭스를 포뮬레이션 하는 것을 목적으로 하고 있다. 연구 결과, 새로운 유기 솔더 보존제의 플럭싱에는 메탄올의 함량비가 높아질수록 플럭싱이 더 우수해지는 경향을 나타내었다.

Improvement of Dimensional Stability of Acacia mangium Wood by Heat Treatment: A Case Study of Vietnam

  • Tran, Van Chu
    • Journal of Forest and Environmental Science
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    • 제29권2호
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    • pp.109-115
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    • 2013
  • Fast-grown wood generally contains a high proportion of juvenile wood that results in inferior dimensional stability and durability against biological deteriorations. In the present research, the Acacia mangium wood from plantation forests in Vietnam was treated with high temperature in air. The effects of heat treatment on physical properties of Acacia mangium wood, including mass loss (ML), water absorption (WA), water-repellent effectiveness (WRE) and anti-swelling efficiency (ASE) were examined. The results showed that the dimensional stability and the water-repellent effectiveness are increased by about 15-46% and 8-18%, respectively. However, the mass and dimension of wood are decreased. The results also indicated that both treatment temperature and treatment duration significantly affect the wood properties of Acacia mangium. It is thus concluded that heat treatment demonstrates an interesting potential to improve the wood quality of Acacia mangium for solid timber products. This technology provides an environmentally safe method of protecting sustainable common woods to give a new generation of value-added biomaterials with increased stability without the use of toxic chemicals.

Community changes in carabid beetles (Coleoptera: Carabidae) through ecological succession in abandoned paddy fields

  • Do, Yu-No;Jeong, Kwang-Seuk;Lineman, Maurice;Kim, Ji-Yoon;Kim, Hang-Ah;Joo, Gea-Jae
    • Journal of Ecology and Environment
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    • 제34권3호
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    • pp.269-278
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    • 2011
  • Carabid beetle community changes in paddy fields, abandoned paddy fields, and mountains were investigated to understand differences in species diversity and composition of different habitat types in small agricultural landscapes in South Korea. A total of 2,938 individuals from 37 species were identified and classified from the studied habitats. Diversity in the mountains was higher than that in abandoned paddy fields. As the number of years since abandonment increased, the diversity and stability of the carabid beetle community also increased. Abandoned paddy fields in some paddy field areas and adjoining mountainous areas, left with preconditions for management and control, have provided the opportunity to improve the diversity and habitat of small agricultural landscapes. Species composition changed continuously from the paddy fields to the mountains, in accordance with individual species habitat preferences. Abandoned paddy fields in small agricultural landscapes are believed to play an important role as transitional buffer zones between paddy fields and the adjacent mountainous areas.