• Title/Summary/Keyword: 미세제조

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Effect of Emulsifiers on Characteristics of Microcapsule Containing Squid Liver Oil as a Core Material (유화제 종류에 따른 오징어 간유의 미세캡슐화 특성)

  • Hwang, Sung-Hee;Lee, Ki-Teak;Youn, Kwang-Sup
    • Korean Journal of Food Science and Technology
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    • v.39 no.1
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    • pp.29-32
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    • 2007
  • This study was carried out to investigate the effect of emulsifiers on the characteristics of microcapsule containing squid liver oil. The emulsion stability of glycerine monostearate (HLB 4) separated after 1 hr. Sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate=6:4; HLB 11), sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate=7:3; HLB 16) and glycerine monostearate (HLB 4) plus sucrose fatty acid esters (monostearate: di-, tri-, and tetrastearate= 7:3; HLB 16) separated after 1 hr 30 min. The microencapsulation efficiency prepared by HLB 16 was 35.0%. The polyunsaturated fatty acid composition was shown to be higher than 50% in all powders, and the ratio of the polyunsaturated fatty acid composition to the saturated fatty acid composition was found to be the same (2.07) for HLB 11 and HLB 16.

Feasibility Study on Surface Microcrack Detection of the Steel Wire Rods Using Electromagnetic Acoustic Resonance (전자기 음향 공진을 이용한 강선의 표면 미세 결함 탐상 타당성 연구)

  • Heo, Taehoon;Cho, Seung Hyun;Ahn, Bongyoung;Lim, Zhong Soo
    • Journal of the Korean Society for Nondestructive Testing
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    • v.33 no.1
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    • pp.7-13
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    • 2013
  • The surface microcrack over a few tens of micrometers is one of severe problems of a steel wire rod to lead to the failure of the final products, so the method to evaluate crack depth has been required to develop. This work investigates the feasibility of electromagnetic acoustic resonance (EMAR) for this problem. EMAR is the method for measurement of resonant features using electromagnetic acoustic transducer (EMAT). Generally, EMAR is sensitive to small variation of the structures and easy to apply it to the industrial field because of the feature of noncontact measurement. Through several EMAR experiments, the change of the resonant frequencies and attenuation in reverberation has been observed. The results confirms that the surface cracks of around 100 micrometer depth can be detected successfully with the present method.

Drug Release Behavior and Degradability of Microspheres Prepared using Water-Soluble Chitosan (수용성 키토산으로 제조한 미세구의 분해성과 약물 방출 거동)

  • 장미경;최창용;김원석;정영일;나재운
    • Polymer(Korea)
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    • v.28 no.4
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    • pp.291-297
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    • 2004
  • Water-soluble chitosan micro spheres were prepared by emulsification of chitosan solution in mineral oil followed by cross linking reaction with different amount of the cross linking agent (glutraraldehyde), different chitosan concentration. Then, the physicochemical properties such as morphological change by degradation, drug loading efficiency, and drug release profiles were investigated with the drug loaded water-soluble chitosan microspheres. Norfloxacin loaded water-soluble chitosan micro spheres showed excellent drug entrapping capacities without burst release caused by surface bound drug. The absence of the surface bound drug also confirmed by X-ray diffraction study. Degradation and drug release studies showed that the amount of the crosslinking agent played a crucial role for drug loading, release and degradation. The water-soluble chitosan micro spheres showed more sustained drug release profiles with slower degradation and larger particle size by increasing crosslinking agent.