• 제목/요약/키워드: Swollen surface

검색결과 54건 처리시간 0.024초

Poloxamer를 이용한 Swollen Micelle의 Tocopheryl Acetate 안정화 (Stabilization of Tocopheryl Acetate of Swollen Micelle by Poloxamer)

  • 김미선;윤경섭
    • 한국응용과학기술학회지
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    • 제36권2호
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    • pp.609-622
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    • 2019
  • 계면활성제가 수용액 중에 용해되면 용액 내에서 micelle (< 20 nm) 이라는 응집체를 형성하며, micelle은 그 내부에 활성물질을 담지하여 가용화 제형이 형성될 수 있다. Swollen micelle은 50~100 nm 정도로 일반 가용화 제형보다 더 많은 양의 활성물질을 담지할 수 있는 제형이다. Swollen micelle은 고압유화와 같은 별도의 공정이 필요한 liposome이나 nanoemulsion과는 달리 특별한 공정이 필요 없어 생산적인 면에서 좀 더 효율성 있는 가용화 및 입자형성 방법이라고 할 수 있다. 본 연구에서는 Poloxamer 407을 이용하여 swollen micelle 제형에 대한 안정화 실험을 진행한 후, Response Surface Methodology (RSM)을 이용하여 tocopheryl acetate 가용화에 대한 제형 최적화 실험을 진행하였다. 가용화에 영향을 주는 계면활성제와 활성물질인 tocopheryl acetate를 요인(factor)로 설정하고 서로 간의 상관관계를 확인하였다. 평가방법으로서 온도 및 시간에 따른 안정성과 입자 분포 및 크기를 확인하였으며, FIB를 통해 효능 물질을 담지한 swollen micelle의 입자 구조 및 모양을 확인하였다. 이러한 실험 결과들을 통하여 tocopheryl acetate를 안정화시킨 swollen micelle은 poloxamer 407 0.500%, octyldodeceth-16 0.387%, tocopheryl acetate 0.945%일 때 가장 최적화된 처방이라 할 수 있다.

외대버섯속의 담자포자의 발생과 미세구조 (Basidiospore Development and Fine Structure of Entoloma)

  • 조덕현
    • 한국자원식물학회지
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    • 제6권2호
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    • pp.141-145
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    • 1993
  • Apexes of basidia in Rhodophyllus(synonyum of Entoloma) muraii var. albus are divided into four sections or depressed in the center. A spore is formed by inflation of the apex of the sterigma. The apex of the sterigma is swollen and changed from a papilla through a penisform and a club into a globeform. Six spots of globose spore are regularly or irregularly depressed with hilum axes. Finally the spores are cuboid. Basidia of Entoloma squamiferrum are developed from hymenium layer of crator-shaped parabasidium. Apex of basidium is flat or depressed in the center. Although four sterigmata are developed, only two sterigmata are symmetrically swollen to two spores in certain basidia. It means that two sterigmata among four sterigmata are infertile. The apex of the sterigma is swollen into a paillaform, and then turned into a penisform. It is swollen from a clubform into a globeform. Six spots of the surfaces of globose spore are deperssed with hilum axes. Finally the spore is cuboid, and then it is released from hilum. Four sterigmata of papillaform of E. violaceobrunneum are developed from cartor-shaped basidium. The apex of sterigma is swollen to a small globeform. And then it is swollen to a clubform. The clubform is again swollen to a ellipticalform, and then more than six spots of spore surfaces are ramomly depressed with hium axes. When the depression of surface of a elliptical spore is over, it is the multi-angular spore of the heterometrical-form.

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회주철의 수축결함생성에 미치는 주조방안 및 화학조성의 영향 (Effects of Risering Design and Chemical Composition on Formation of Shrinkage Cavity in Gray Cast Iron)

  • 류성곤
    • 한국재료학회지
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    • 제13권5호
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    • pp.297-302
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    • 2003
  • The effects of risering design and alloying element on the formation of defects such as external depression, primary and secondary shrinkage cavity in gray cast iron were investigated. Two types of risering design for the cylindrically step-wise specimen, No. 1(progressive solidification) and No. 2(directional solidification) risering designs, were prepared and five different alloy compositions were casted. In the No. 1 risering design, external depression or primary shrinkage cavity due to liquid contraction was observed in all the specimens from ISO 150 to ISO 350. The primary shrinkage cavity was located right under the top surface or connected to the top surface, and was characterized by smooth surface. Its size increased with an increase in ISO number. However, neither secondary shrinkage cavity nor swollen surface was observed in all the castings. In the No.2 risering design, neither primary shrinkage cavity nor secondary shrinkage cavity was observed in all the specimens due to proper risering design. A swollen surface was also not observed in all the castings with the application of pep-set mold.

황보라 외대버섯의 담자포자의 발생과 미세구조 (Basidiospore Development and Fine Structure of Entoloma violaceobrunneum)

  • 조덕현;권선방
    • 한국자원식물학회지
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    • 제6권1호
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    • pp.83-86
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    • 1993
  • Four sterigmata of papillaform E. violaceobrunneum are developed from crator-shaped basidium. The apex of sterigma is swollen to a small globeform. And then it is swollen to a clubform. The clubform is again swollen to a ellipticalform, and then more than six spots of spore surfaces are ramdomly depressed with hilum axes. When the depression of surface of a elliptical spore is over, the spore is a heterodiametrical spore of multi-angular.

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구상흑연주철의 수축결함생성에 미치는 주조방안 및 합금원소의 영향 (Effects of Risering Design and Alloying Element on Formation of Shrinkage Cavity in Ductile Cast Iron)

  • Yu, Sung-Kon
    • 한국재료학회지
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    • 제13권2호
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    • pp.74-80
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    • 2003
  • The effects of risering design and alloying element on the formation of defects such as external depression, primary and secondary shrinkage cavities in ductile cast iron were investigated. Two types of risering design for the cylindrically step-wise specimen, No. 1(progressive solidification) and No. 2(directional solidification) risering designs, were prepared and six different alloy compositions were casted. In the No. 1 risering design, external depression or primary shrinkage cavities due to liquid contraction were observed in all the specimens from SG 10 to SG 60. The defects caused by liquid contraction seemed to be more affected by risering design than alloying elements. The secondary shrinkage cavities were also observed in all the specimens but a swollen surface was not observed in all the castings. The primary shrinkage cavities were located right under the top surface or connected to the top surface, and were characterized by smooth surfaces. On the other hand, the secondary shrinkage cavities were positioned in the thermal center of the specimen steps 3 and 4, and characterized by rough surfaces. In the No. 2 risering design, no external depression or primary shrinkage cavities due to liquid contraction were observed in all the specimens from SG 10 to SG 60. However, the secondary shrinkage cavities were formed in the thermal center of specimens SG 40, 50 and 60. Like the No. 1 risering design, a swollen surface was not observed in all the castings.

팽윤 Extrusion 전분을 기질로 한 불균일상 효소반응계에서의 Maltose 생성 반응 특성 (Characteristics of Maltose Formation in Heterogeneous Enzyme Reaction System Utilizing Swollen Extrusion Starch as a Substrate)

  • 김동선;박동찬;조명진;이용현
    • 한국미생물·생명공학회지
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    • 제22권3호
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    • pp.283-289
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    • 1994
  • The production of maltose utilizing swollen extrusion starch seems to have many technical advantages, such as, high reaction rate and high yield, production of high purity concentrated maltose, and low energy consumption, over the conventional method utilizing liquefied starch. The characteristics of maltose formation in heterogeneous enzyme reaction system comtaining swollen extrusion starch was investigated using fungal $\alpha $-amylase. The influence of extrusion conditions on structure of extruded starch, such as, degree of gelatinization, water absorption index, and water solubility index was analyzed. The relationship between the structural features and maltose forming reaction was investigated, and the result was analyzed in terms of surface reaction of insoluble extruded swollen starch. The characteristics of maltose formation from swollen sxtrusion starch was compared using endo-type fungal $\alpha $-amylase and exo-type $\beta $anylase, and the structural trasformation of extruded starch was also observed to clarify the reaction mechanism.

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Micelle 형성에 관한 현상학적 고찰 (A Phenomenological Study on Micellization and Solubilization)

  • 김명수
    • 대한화학회지
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    • 제33권5호
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    • pp.459-467
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    • 1989
  • 계면활성제가 수용액 중에 용해되면 용액내에서 micelle이라는 응집체를 형성하며, micelle은 그 내부에 oil를 용해시켜 swollen micelle을 형성하게 된다. 실제로 물-oil-계면활성계의 상평형도상에서 micelle과 swollen micelle은 동일영역에 존재하게 되나 일반적으로 micelle과 swollen micelle의 형성에 관해서는 서로 다른 관점으로 취급되어 왔다. 본 연구에서는 이러한 계면활성제 응집체의 형성에 관한 일관된 열역학적 모델을 제시하고자 한다. 모든 경우에 저농도 영역에서 이상용액 이론을 적용하였으며, micelle 형성에너지는 소수성 작용에너지와 계면에서의 표면에너지의 합으로 표시하였다. 이론식으로부터 임계마이셀농도, 평균응집분자수, 용해비 등을 예측하였으며 실험관측치와 비교하였다.

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Histology and Morphometries of the Epidermis of the Fins and Sucking Disc of the Mudskipper, Periophthalmus modestus (Pisces, Gobiidae)

  • Park, Jong-Young;Kim, Ik-Soo;Lee, Yong-Joo;Kim, So-Young
    • Animal cells and systems
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    • 제8권2호
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    • pp.111-115
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    • 2004
  • The epidermis of the mudskipper, Periophthalmus modestus, consists of three layers- the outermost layer, middle layer and stratum germinativum. Extensive fine blood capillaries are present near the superficial layer of epidermis and outermost layer in five fins and a sucking disc. The diffusion distance between the vascular capillaries and the surface of epidermis ranged from 3.6 to 10.9${\mu}$m: 3.6 ${\mu}$m in the sucking disc, 10.9 ${\mu}$m in the anal fin and 4.6 to 5.0 ${\mu}$m in the two dorsal fins. Rate of the surface area of respiratory epithelium, the surface area of the fine blood capillaries occupied per surface area of epidermis in 0.1mm, is 3.7 to 4.4% in two dorsal fins and 1.1% in the anal fin. The middle layer is simpler in structure consisting of small or voluminous cells swollen by epidermal cells, and this layer appeared web-like. Well-developed lymphatic spaces containing lymphocytes existed in the stratum germinativum. The five fins and sucking disc had no epidermal glands.

Fabrication of three-dimensional electrical patterns by swollen-off process: An evolution of the lift-off process

  • Mansouri, Mariam S.;An, Boo Hyun;Shibli, Hamda Al;Yassi, Hamad Al;Alkindi, Tawaddod Saif;Lee, Ji Sung;Kim, Young Keun;Ryu, Jong Eun;Choi, Daniel S.
    • Current Applied Physics
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    • 제18권11호
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    • pp.1235-1239
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    • 2018
  • We present a novel process to fabricate three-dimensional (3D) metallic patterns from 3D printed polymeric structures utilizing different hygroscopic swelling behavior of two different polymeric materials. 3D patterns are printed with two different polymers as cube shape. The surface of the 3D printed polymeric structures is plated with nickel by an electroless plating method. The nickel patterns on the surface of the 3D printed cube shape structure are formed by removing sacrificial layers using the difference in the rate of hygroscopic swelling between two printing polymer materials. The hygroscopic behavior on the interfaced structure was modeled with COMSOL Multiphysics. The surface and electrical properties of the fabricated three-dimensional patterns were analyzed and characterized.

Morphological and Cytochemical Study on the Skin of Korea Eel Goby, Odontamblyopus lacepedii(Pisces, Geobiidae)

  • Park, Jong-Young;Lee, Yong-Joo-Ik-Soo;Kim, So-Young;Kim, So-Young
    • Animal cells and systems
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    • 제7권1호
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    • pp.43-47
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    • 2003
  • The skin of the eel goby, Odontamblyopus lacepedii, consists of epidermis, dermis and subcutis. The epidermis has three layers: the outermost layer, middle layer and stratum germinativum. The outermost layer is composed of polygonal cells or rather flattened cells, and mucous gland cells of acid mucopolysaccharides. The middle layer consists mainly of swollen small or voluminous epidermal cells and shows a web-shaped structure. The thickness of the epidermis depends on the various sizes and the number of layers of the swollen cells. Well-developed lymphatic spaces containing lymphocytes exist in the stratum germinativum and small scales are embedded in the dermis. A large number of blood capillaries are present just below the basement membrane, and a definite area giving AB and PAS positive was present between the basement membrane and scales, Taste buds ave distributed on surface of the epidermis at intervals. Considering the structural features of the skin, it may be considered that O. lacepedii is more likely to be related to cutaneous respiration as a dual respiratory system.