• Title/Summary/Keyword: emulsion method

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Preparation and Characteristics of Poly(ε-caprolactone) Microcapsules Containing Pseudomonas by W/O/W Emulsion (다중에멀젼법을 통한 슈도모나스를 함유하는 PCL 마이크로캡슐의 제조 및 특성 연구)

  • Kim, Ki-Seok;Lee, Seung-Yeop;Lee, Gun-Woong;Kim, Hyung-Gon;Park, Soo-Jin
    • Polymer(Korea)
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    • v.36 no.2
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    • pp.202-207
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    • 2012
  • Biodegradable poly(${\varepsilon}$-caprolactone)(PCL) microcapsules containing pseudomonas were prepared by W/O/W emulsion system. The characteristics and release behaviors of the microcapsules were investigated as a function of manufacturing conditions. The morphology and particle distribution of the microcapsules were observed by a scanning electron microscope and a particle size analyzer. The release behaviors of the pseudomonas were determined using a cell culture method. It was found that smooth and spherical microcapsules were formed by W/O/W emulsion system and particle size was in the range of 10 to 60 ${\mu}m$. The release behaviors of the pseudomonas were influenced by the manufacturing conditions. It was indicated that the increase of the surfactant content and stirring rate led to an increased release rate, resulting from the high specific surface area of the smaller particle size, and the increase of the PCL content provided the sustained release behaviors by the delay effect of diffusion in the release medium.

The Effects of the Properties Changing of Coated Paper and Ink Emulsion of IPA on Printed Mottle (도공지 물성 변화와 IPA에 의한 잉크 유화가 인쇄 모틀에 미치는 영향)

  • Ha, Young-Baeck;Lee, Euy-Soo;Oh, Sung-Sang;Koo, Chul-Whoi;Youn, Jong-Tae
    • Journal of the Korean Graphic Arts Communication Society
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    • v.26 no.2
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    • pp.1-13
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    • 2008
  • Printed mottle of coated paper is one of the most common phenomenon and the most difficult problem in offset printing. Offset printing is processed mainly processed by the attractive properties between water and oil, so all inks for off-printing must work with dampening solution(water). It may cause the emulsion on the printing nip from the printing pressure. This study aimed to investigate the effect of emulsified inks on print mottle from emulsified cyan ink by force with each different IP A contents. We measured the print mottle by densitometer and image analysis method. The emulsified inks also give effect to now properties of inks and it caused more ink transfer rate, however, it caused low density of inks. Moreover the emulsified inks were spreaded to around of dots and cause the thinning density on the non-printing area like print mottle. The results showed that the emulsified inks also cause scumming on the printing result with little mistake of adjusting dampening solution and mostly decreasing dot reproduction. So we could find out the obvious effect of emulsified inks to print mottle.

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A Case Study of Minimizing Construction Time in Long and Large Twin Tube Tunnel (대단면 장대터널 공기단축 사례연구)

  • No Sang-Lim;Noh Seung-Hwan;Lee Sang-Pil;Kim Moon-Ho;Seo Jung-Woo
    • Tunnel and Underground Space
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    • v.15 no.3 s.56
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    • pp.177-184
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    • 2005
  • The Sapaesan tunnel, the longest twin tube tunnel (4km) in Korea with 4 lanes each, is under construction with two years of delayed schedule because of the strong opposition from environmental bodies. Therefore, maximizing the construction efficiency was needed in tunnel project to compensate for time delay. This study includes improvements in the construction of the Sapaesan tunnel such as increasing excavation length and changing excavation sequence. In this paper the system for predicting tunnel face ahead is also introduced. Bulk-Emulsion explosive and Cylinder-Cut method were adopted in tunnel blasting to increase the excavation length. Optimum tunnel excavation step was designed to make up delayed time. Tunnel foe mapping, TSP survey and geological prediction system using computerized jumbo-drill were performed fnr safe construction of long and large twin tube tunnel.

Coagulation of Cationic Rosin Emulsion and its Effect on Ink Receptivity of Coating Layer (양이온성 로진 에멀션의 응결현상이 도공층의 잉크흡수성에 미치는 영향)

  • 박철웅;이학래
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.30 no.3
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    • pp.74-83
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    • 1998
  • The phenomenon of decrease in sizing efficiency when the stock temperature is increased is well recognized as summer sizing, and this is believed to be caused by uneven distribution of sizing agents on paper surface most often incurred by coagulation of sizing agents. When unevenly sized paper is used as coating base stock, nonuniform consolidation of the coating layer may result, which, in turn, causes uneven distribution of binder on coating surface. This causes nonuniform ink absorption to produce print mottle. In this study the effects of simple or polymeric electrolytes, storage temperature and time on the coagulation of cationic dispersed rosin size were investigated using a turbidity measurement method which was verified to correlate well with the particle size of rosin emulsion or its coagulates. Handsheets sized with rosin dispersions coagulated under various conditions were prepared and their sizing degree and coated paper properties including gloss and ink density were examined. The relationship between the sizing nonuniformity of coated papers and its ink absorption property was evaluated. Turbidity of rosin emulsion increased as the storage temperature and time were increased. Addition of simple or polymeric electrolytes caused reduction in $zeta$ -potential of the rosin dispersion and accelerated the coagulation tendency substantially. Reversion of the $zeta$ -potential of rosin dispersion, however, did not occur when coagulation was induced with simple electrolytes. On the other hand, addition of an anionic polyelectrolyte reversed the $zeta$ -potential of the flocculated rosin dispersion. This indicated that electrical double layer compaction and bridging flocculation were coagulation mechanisms for simple and polymeric electrolytes, respectively. Sizing degree decreased as coagulation of rosin was increased. Paper gloss, ink gloss and ink density were increased when sizing degree of base stock was increased most probably due to prevention of base paper swelling and increased binder migration to coating surface. This suggested that uneven printing ink density occurred when uneven sizing development was induced by coagulation of rosin particles.

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Film Image Transfer System (FITS): An Efficient Method for Proper Positioning of Orthodontic Mini-implants

  • Go, Taek-Su;Kim, Seong-Hun;Nelson, Gerald
    • Journal of Korean Dental Science
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    • v.4 no.1
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    • pp.20-25
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    • 2011
  • Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning of the orthodontic mini-implant in the narrow interdental space and considerations for better application. Materials and Methods: A patient who was planning to have orthodontic mini-implant treatment on the posterior maxilla was recruited to assess the feasibility of FITS. Dental radiographic film and bite record was taken. And then the film image was transferred on the photographic emulsion coated model using transfer light through film projector (enlarger). After exposing the photo emulsion coating on the model, the image was developed with a working solution for a paper developer and fixed. The surgical guide for the mini-implant was fabricated from the transported FITS data. Results: The completed surgical guide was easily placed intraorally, and allowed a simple and rapid placement of the mini-implant. The site of the implant placement was accurate as planned position. Conclusion: In the reported case, The FITS technique represents an effort to minimize risk to the patient and produce consistently good results based upon accurate information about the anatomy of the implant site.

Applications of Extracellular Polysaccharide p-m10356

  • Park, Hee-Jung;Kim, Hyong-Ju;Lee, Chang-Moon;Kim, Jin;Lee, Hong-Kum;Yim, Joung-Han;Lee, Ki-Young
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.566-569
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    • 2005
  • The extracellular polysaccharide...(EPS) has been used in a wide variety of industrial applications because of gel formation, emulsion stability, control of the surface tension, water absorption and film formation etc. In this study, inhibitory activity on tyrosinase and inhibitory activity on angiotensin converting enzyme...(ACE) are determined. UV adsorption wavelength, beads formation of EPS were investigated. In the result, in 1%(w/v) EPS concentration, EPS had inhibitory activity of 71.8% on tyrosinase and inhibitory activity of 61.5% on angiotensin converting enzyme in 1.5% EPS concentration. Adsorption wavelength of EPS was UV-B,C . Beads based on EPS were prepared by w/o emulsion method and the shape of EPS beads observed by SEM was spherical and uniform.

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Effects of Seed-treatment Fungicides on Bakanae Disease of Rice

  • Park, Hyo-Won;Shim, Hong-Sik;Kim, Yong-Ki;Yeh, Wan-Hae;Kim, Choong-Hoe
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.91.1-91
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    • 2003
  • Bakanae disease, caused by Gibberella fujikuroi (anamorph Fusarium moniliforme J. Sheldon), a typical seed-borne disease of rice occurs from nursery to paddy fields. Consequently, chemical seed disinfectants is the most efficient control method. Several seed treatment methods with various fungicides were attempted to inhibit disease. Spray and 24 hrs immersion of seeds using prochloraz emulsion reduced disease infection and the control value were 99.3 and 100%, respectively. In contrast, dressing to wet seeds thiophanate-methyl+thiram wp and benomyl+thiram wp reduced disease infection more effectively than 24 hrs immersion of seeds. However, dressing of carpropamid+imidacloprid+fludioxonil wp to wet seeds did not reduced disease as well as wettable liquid of fludioxonil. The results suggest that the bakanae disease might be disinfected effectively by 24 hrs immersion of seeds in prochloraz emulsion and seed dressing of fungicides.

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Preparation and Characterization of Rosiglitazone-loaded PLGA Nanoparticles (Rosiglitazone약물을 함유한 PLGA 나노입자 제조 및 분석)

  • Shin, Ko-Eun;Huh, Kang-Moo;Lee, Yong-Kyu
    • KSBB Journal
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    • v.23 no.5
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    • pp.408-412
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    • 2008
  • The rosiglitazone loaded poly (lactide-co-glycolide) (PLGA) nanoparticles (NPs) were prepared by the emulsion-evaporation method and optimized for particle size and entrapment efficiency. The optimized particles were 140-180 nm in size with narrow size distribution and 80% entrapment efficiency at 1% w/w initial drug loading when prepared with 1-3% w/v of PVA as a surfactant. These particulate carriers exhibited controlled in vitro release of rosiglitazone for 36 hrs at a nearly constant rate after 4 hrs release. In conclusion, these results indicate that PLGA NPs have greater potential for oral delivery of rosiglitazone.

Droplet Size and Thermal conductivity Measurements of Binary Nanoemulsion (이성분 나노에멀전의 입도 및 열전도도 측정)

  • Cho, Chang-Hwan;Sul, Hea-Youn;Jung, Jung-Yeul;Kang, Yong-Tae
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.815-820
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    • 2009
  • Binary nanoemulsions which are defined as the, oil-droplet suspensions in binary solution ($H_2O$/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel two-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. Polymer is used as a steric stabilizer to stabilize the oil-droplets in a strong electrolyte ($H_2O$/LiBr). It is found that the thermal conductivity of the binary nanoemulsion is inversely proportional to the emulsion size while the concentrations of oil and $H_2O$/LiBr are less dominant for the thermal conductivity of binary nanoemulsions.

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Extraction and Isolation of Antioxidant Fraction from Waste of Grape Products for Cosmetic Application (포도가공 부산물로부터 화장품용 항산화물질의 추출 및 분리)

  • Kim, Eui-Jin;Lee, Tae-Ho;Shin, Hyun-Jae
    • KSBB Journal
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    • v.24 no.5
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    • pp.477-482
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    • 2009
  • Anthocyanin and origomeric proanthocyanidin (OPC) fractions showing antioxidizing activity are present in grape extracts. Grape extracts are widely used in cosmetic applications as functional ingredients. The aim of our study is to isolate the antioxidant fraction from waste of grape products. The extraction was done using soxhlet apparatus. Next, the extraction was subjected for identification of antioxidants by using HPLC. Antioxidant assay was performed by using 2,2-diphenyl-picryl-hydrazyl (DPPH) and superoxide dismutase (SOD) method. Antioxidizing activity was found to be higher in grape seed extract when compared to grape skin extract. Using the extract, a novel formula with multi lamella emulsion structure has been developed and its safety and stability were confirmed by standard protocols.