• Journal of Pharmaceutical Investigation
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• 제19권1호
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• pp.29-37
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• 1989

For the prevention of the aggregation during microencapsulation, the effects and role of polyisobutylene(PIB), as a protective colloid, were studied. The effects of sealant treatment on the microencapsulation were studied. Methyldopa was microencapsulated with ethylcellulose (EC) by polymer deposition from cyclohexane by temperature change using PIB. The EC-microencapsulated methyldopa was sealed with spermaceti. The dissolution of methyldopa was influenced by the drug to wall ratio. When PIB was used, low aggregation of microcapsules occurred and the surface was smooth with a few pores. Treatment of microcapsules with spermaceti retarded the release of methyldopa, the release being affected by the percentage of sealant used and the particle size of the product.

• Journal of Pharmaceutical Investigation
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• 제21권4호
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• pp.253-262
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• 1991

Microencapsulation of sodium ascorbate with cellulose acetate phthalate(CAP) by coacervation/ phase separation method were carried out. Various factors affecting microencapsulation, i.e., surfactant concentration. CAP concentration, stirring speed and treatment of spermaceti as a sealing agent were studied. Dissolution rate. particle size distribution, surface feature and stability test were investigated. CAP microcapsules prepared using 0.5% span 80 as a surfactant showed smooth and round surfaces. The release of sodium ascorbate was retarded by microencapsulation with CAP and by sealant treatment with spermaceti. When triturated with sodium bicarbonate, CAP microcapsules were more stable than unencapsulated sodium ascorbate under various RH conditions at $37^{\circ}C$.

• 한국음향학회지
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• 제39권6호
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• pp.533-540
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• 2020

향고래 전장은 향고래가 발생시키는 클릭의 다중 펄스 구조로 인한 펄스 간 간격(Inter-Pulse Interval, IPI)을 이용하여 추정할 수 있다. IPI는 고래 머리 내부의 경랍에서 왕복 이동시간에 의한 시간지연으로 인해 발생하며, 향고래의 전장과 두장의 비례관계를 이용하여 향고래의 전장을 추정한다. 본 연구에서는 2017년 동해, 포항 앞바다에서 발견된 향고래의 크기를 추정하기 위해 현장에서 측정한 클릭 신호를 분석하였다. IPI와 향고래 크기의 관계식에 의해 계산된 향고래의 전장은 성체 암컷 또는 유년기 수컷의 크기인 9.9 m ~ 10.9 m로 추정되었다. 이 방법은 향고래에게 치명적이지 않으며 크기 추정에 대한 정확성이 검증되었으므로, 국내 향고래 모니터링에 유용한 정보를 제공할 수 있다.