• 제목/요약/키워드: Moisture permeation

검색결과 48건 처리시간 0.024초

수분 감응성 아시클로버 패취제의 설계 및 평가 (Formulation and Evaluation of Moisture-activated Acyclovir Patches)

  • 김아미;곽혜선;전인구
    • Journal of Pharmaceutical Investigation
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    • 제36권6호
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    • pp.393-399
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    • 2006
  • This study was aimed to design, formulate and characterize the moisture-activated patches containing acyclovir for antiviral action. Gel intermediates for film-type patches were prepared with mucoadhesive polymer, viscosity builders, enhancers and acyclovir. Patches containing acyclovir were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane, and of drug flux through the hairless mouse skin. Film-type patches obtained were uniform in the thickness and showed a mucoadhesive property when contacted with moisture. The formulation was optimized, which consisted of $Cantrez^{\circledR}$ AN-169(2%), $Kollidon^{\circledR}$ VA 64(1%), $Natrosol^{\circledR}$(1%), hydroxypropyl-$\beta$-cyclodextrin(1%) and dimethylsulfoxide(0.5%). Release rates of acyclovir patches increased dose-dependently. The addition of terpenes such as d-limonene or cineole increased release rates of acyclovir, but decreased permeation rates. The permeation rates were enhanced by 2 and 2.5 times by the addition of glycyrrhizic acid ammonium salt and sodium glycocholate, respectively, compared with that of no enhancer. These results suggest that it may be feasible to deliver acyclovir through the skin or gingival mucosa from the moisture-activated patches.

Characterization and Evaluation of Freeze-dried Liposomes Loaded with Ascorbyl Palmitate Enabling Anti-aging Therapy of the Skin

  • Lee, Sang-Kil;Lee, Jae-Hwi;Choi, Young-Wook
    • Bulletin of the Korean Chemical Society
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    • 제28권1호
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    • pp.99-102
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    • 2007
  • To prepare freeze-dried ascorbyl palmitate (AsP)-containing liposome which can protect the drug from moisture attack and be used instantly by mixing with water for anti-aging and skin whitening therapy, AsP was encapsulated into liposomes and freeze-dried with trehalose. The freeze-dried liposome formulations were characterized by measuring water contents, particle size, time required for complete reconstitution. With the freeze-dried liposomes, we performed the stability test under accelerated conditions, skin permeation and localization test. The measurement of the time to perfect reconstitution showed that the freeze-dried liposomes can be changed to their initial state rapidly and short term stability test of AsP in reconstituted liposomes under accelerated conditions confirmed that the stability of AsP was considerably enhanced as compared to freshly prepared liposomes. The skin permeation and localization properties of AsP in reconstituted liposomes were not significantly different, indicating that the liposomal structures were maintained before and after freezedrying. In conclusion, the freeze-drying method provided a possible way to overcome the instability issue of AsP induced by the moisture and reproduced similar skin permeation and localization properties as shown by freshly prepared liposomes.

Permeabilities of Korean Earthenware Containers and Their Potential for Packaging Fresh Produce

  • Seo, Gyeong-Hee;Chung, Sun-Kyung;An, Duck-Soon;Lee, Dong-Sun
    • Food Science and Biotechnology
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    • 제14권1호
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    • pp.82-88
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    • 2005
  • Ethnic Korean onggi earthenwares were fabricated using different clay formulations and glazing treatments. Their permeability properties against oxygen, carbon dioxide, and moisture were measured at $20^{\circ}C$ and examined from the aspect of food preservation. Onggi walls consisted of micropores that offered higher gas and moisture permeation rates when compared with other food packaging materials. Earthenware walls were unique in having $CO_2/O_2$ permeability ratios of 0.60-1.00. Gas and moisture permeabilities were lower, with wall structure having lower porosity and surface glazing. Results revealed onggi jar packages of grape fruits could attain wide range of $O_2$ and $CO_2$ concentrations. Onggi containers present good opportunity to obtain optimum packaging conditions for respiring or ripening products, depending on commodity type.

Mechanical Tenacity Analysis of Moisture Barrier Bags for Semiconductor Packages

  • Kim, Keun-Soo;Kim, Tae-Seong;Min Yoo;Yoo, Hee-Yeoul
    • 마이크로전자및패키징학회지
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    • 제11권1호
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    • pp.43-47
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    • 2004
  • We have been using Moisture Barrier Bags for dry packing of semiconductor packages to prevent moisture from absorbing during shipping. Moisture barrier bag material is required to be waterproof, vapor proof and offer superior ESD (Electro-static discharge) and EMI shielding. Also, the bag should be formed easily to the shape of products for vacuum packing while providing excellent puncture resistance and offer very low gas & moisture permeation. There are some problems like pinholes and punctured bags after sealing and before the surface mount process. This failure may easily result in package pop corn crack during board mounting. The bags should be developed to meet the requirements of excellent electrical and physical properties by means of optimization of their raw material composition and their thickness. This study investigates the performance of moisture barrier bags by characterization of their mechanical endurance, tensile strength and through thermal analysis. By this study, we arrived at a robust material composition (polyester/Aluminate) for better packing.

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유구 이전용 에폭시 폴리머의 토양 침투도와 관련된 물성에 관한 고찰 (Study on the Physical Property of Epoxy Polymer Related with Degree of Permeation to Soil for Moving Historical Site)

  • 위광철;서정호
    • 보존과학회지
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    • 제25권2호
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    • pp.155-160
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    • 2009
  • 유구의 지속성과 안정성을 높이기 위하여, 저점도 Epoxy인 SE-101의 토양의 입자 크기와 수분 함량에 따른 침투성과 전단 강도를 측정하였으며, 이 결과들을 이용하여 SE-101의 사용법을 최적화하고자 하였다. 점도 데이터로부터 충분히 예상되었듯이, 입자의 크기가 증가할수록 침투도는 증가하였으나, 전단 강도는 감소하였으며 특히, 고분자의 불균일한 경화 속도와 내부 무기 첨가제에 따라서 침투도의 편차가 심하여 질 수 있음을 알 수 있었다. 토양 내의 수분 함량이 증가할수록, 침투도와 전단 강도의 편차가 매우 심하여져서 동일 시편 내에서도 매우 취약한 부분이 생성되고, 유구 이전 중의 파손 현상 발생도 예측할 수 있어 이전재의 침투 깊이의 50% 이상은 건조된 상태에서 사용하는 것이 필요한 것으로 보인다.

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변압기 절연지의 수분함량 및 열화에 따른 전기적 특성 연구 (The Electric Characteristics of the Thermal Aged Insulation-Paper with Moisture Content on the Transformer)

  • 김필환;김주한;이병성;이원영;김도영;한상옥
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 C
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    • pp.1909-1911
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    • 2004
  • It is caused that insulation paper, which had got a lot of thermal stress by over-load after installation, should have been deteriorated in electrical and mechanical characteristics. Beside, insulation material is decreased the insulating property and accelerated aging of them in case of dielectric loss when transformers are manufactured with some moisture or transformers would have been them because of moisture-permeation, Therefore, in this study we experienced the influence of moisture content in case of the thermal aged insulation paper. we have measured tan ${\delta}$ and breakdown voltage in the ratio of paper' moisture content before the aging and then taken the same tests again after insulation paper thermally accelerating-aged. There is a purpose to gain data for a life-design and to establish aging mechanism in order to continuously study life expectancy of the insulation paper.

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Prediction of Deterioration Rate for Composite Material by Moisture Absorption

  • Kim, Yun-Hae;An, Seung-Jun;Jo, Young-Dae;Bae, Chang-Won;Moon, Kyung-Man
    • Journal of Advanced Marine Engineering and Technology
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    • 제34권2호
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    • pp.296-302
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    • 2010
  • If the fiber reinforced plastic is exposed to the moisture for a long period of time, most of moisture absorption occurs on the resin place, thus dropping cohesiveness between the molecules as the water molecules permeated between high molecular chains grant high molecular mobility and flexibility. Also as the micro crack occurs due to the permeation of moisture on the interface of glass fiber and epoxy resin, it is developed to the overall damage of interface place. Hence, the study on absorption is essential as the mechanical and physical properties of fiber reinforced composites are reduced. However, the study on absorption has the inconvenience needing to expose composite materials to fresh water or seawater for 1 month or up to 1 year. Therefore, this study has exposed fiber reinforced composites to fresh water and has developed a model with an accuracy of 98% after comparing the analysis value obtained by using ANSYS while basing on the experimental value of property decline by absorption and the basic properties of glass fiber and epoxy resin used in the experiment.

글로우방전을 이용한 폴리에스테르 직물의 투습방수성 개질 (Water Repellent Finish of Polyester Fabric Using Glow Discharge Treatment)

  • 김태년
    • 한국의류학회지
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    • 제25권1호
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    • pp.154-161
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    • 2001
  • We have treated polyester fabric with $CF_4,\;C_2F_6,\;SF_6\;and\;C_3F_6$ glow discharge plasmas to develop functional fabrics which preserve moisture transportation and water proofing nature. Modified properties were evaluated by water vapor permeation rate and breakthrough water pressure. The change of surface morphology was observed by SEM. Fiber interstice of the plasma treated fabric was calculated as $0.32{\mu}{\textrm}{m}$, and this value was sufficiently ideal as water repellent material. The moisture transportation of ${CF_4}-treated$ fabric was good as much as untreated fabric, and those of $C_2$F(sub)6-treated, SF(sub)6-treated fabrics were reduced by 1~3%, and that of ${C_3F_6}-treated$ fabric was reduced by 15%. The best treatment condition were 0.06 torr 120 seconds in $CF_4$, 0.05 torr 30 seconds in $SF_6$, 0.08~0.15 torr 90 seconds in $SF_6$ and 0.1 torr 45 seconds in $C_3F_6$ respectively. The grade of moisture transportation effect was $CF_4>C_2F_6>SF_6>>C_3F_6$, and water proofing effect was $C_2F_6{\approx}CF_4>C_3F_6>SF_6$. It was observed by SEM that the thin film was formed on the surface of the treated substrate by the fluorocarbon plasma treatment.

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열 열화에 따른 유입절연지의 화학적 특성 (Chemical Properties of Insulation Paper in oil after Thermal Aging)

  • 김필환;김재훈;김주한;이원영;한상옥
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기설비전문위원
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    • pp.77-79
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    • 2004
  • It is caused that insulation paper, which had got a lot of thermal stress by over-load after installation, should have been deteriorated in electrical and mechanical characteristics. Beside, insulation material is decreased the insulating property and accelerated aging of them in case of dielectric loss when transformers are manufactured with some moisture or transformers would have been them because of moisture-permeation. Therefore, in this study we experienced the influence of moisture content in case of the thermal aged insulation paper. we have measured tan 6 and breakdown voltage in the ratio of paper' moisture content before the aging and then taken the same tests again after insulation paper thermally accelerating-aged. There is a purpose to gain data for a life-design and to establish aging mechanism in order to continuously study life expectancy of the insulation paper

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