• Journal of the Korean Professional Engineers Association
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• v.24 no.6
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• pp.97-105
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• 1991

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ø70mm on the calcalious sand stone (soft-moderate-semi hard Rock). The total numbers of fire blast were 88 round. Scale distance were induces 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagation Law in Blasting Vibration (Equation omitted) where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum Charge per delay-period of eighit milliseconds o. more(kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D / W$^n$ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three graups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge per delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over 100m distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30 ‥‥‥under 100m ‥‥‥V=41(D/$^3$√W)$\^$-1.41/ ‥‥‥A Over 100 ‥‥‥‥under 100m ‥‥‥V=121(D/$^3$√W)$\^$-1.56/ ‥‥‥B K value on the above equation has to be more specified for furthur understang about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.551-559
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• 1997

The stability of liquid membrane in the extraction process was investigated through the extraction of the Zn component by using W/O/W emulsion type liquid surfactant membrane which was $D_2EHPA-Kerosene-Span$ $80-H_2SO_4$ system. The highest stability for liquid membrane through the Zn extraction process was obtained under the following conditions. That conditions were that span 80 concentration, as surfactant, of 2~3 vol.%;$D_2EHPA$ concentration, as extractant, of 5~7 vol.%;paraffin oil concentration, as membrane strengthening agent, of 10 vol.%;emulsion volume ratio to the external aqueous phase volume of 0.1, and internal aqueous phase volume ratio to the organic phase volume of 1.0.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.945-951
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• 2012

A water emulsion fuel can be used to reduce soot and NOx emissions simultaneously because it has a lower combustion temperature and better fuel atomization owing to the evaporative latent heat and microexplosion of water. Moreover, it can be used without making special modifications to conventional diesel engines. Therefore, this fuel has attracted considerable research attention. In addition, lower-grade fuels are being considered for use in conventional engines because of an increase in oil prices. In this study, we investigated the combustion and exhaust characteristics of MDO (marine diesel oil), which has a lower grade than common diesel oil, and ME (MDO water emulsion) under various test conditions in an automotive diesel engine.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.38.2-38.2
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• 2009

Regeration of natural tissuesor to create biological substitutes for defective or lost tissues and organs through the use of cells. In addition to cells and their porous, drugs are required to promote tissue regeneration. Therefore, the present studies were prepared using simvastatim loaded porous poly(lactide-co-glycolide) (PLGA) by double emulsion solvent evaporation water-in-oil-in-water technique (W/O/W) as drug delivery system strategies for injuring tissue. The resulting microspheres were evaluated for morphology, particle size, encapsulation efficiency, degradation of PLGA microspheres in vitro drug release and in vitro cell viability. Scanning electronic microscopic (SEM) showed that the porosities of the particles was changed by experimental conditions and cultured cells were attached well on porous microspheres surface. The X-ray diffraction (XRD) and differential scanning calometry (DSC) analysis indicate thatsimvastatim was highly dipersed in the microsphere at amorphousstate.

• Journal of Pharmaceutical Investigation
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• v.41 no.6
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• pp.323-329
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• 2011

In order to develop new protein carrier replacing poly(DL-lactic acid-co-glycolic acid) (PLGA) microspheres, succinylated pullulan acetate (SPA) was investigated to fabricate a long term protein delivery carrier. SPA microspheres loaded with lysozyme (Lys) as a model protein drug were prepared by a water/oil/water (W/O/W) double emulsion method. An acidity test of SPA copolymers after hydrolysis was performed to estimate the change of protein stability during releasing proteins from the microspheres. There was no pH change of SPA copolymers, but pH of PLGA polymers after hydrolysis was significantly decreased to around pH 2, indicating that the long-term stability of proteins released from SPA microspheres can be guaranteed. Loading efficiency of proteins into SPA microspheres was three times higher than those into conventional PLGA microspheres, indication of inducing stronger charge interaction between proteins and succinyl groups in SPA microspheres. Although initial burst behaviors were monitored in Lys-loaded SPA microspheres due to relatively strong hydrophilic succinyl segments in SPA microspheres, initial burst issues would be circumvented if the ratio of charge density of succinyl moieties and hydrophobic acetate groups is harmonically controlled. Therefore, in this study, a new attempt of protein delivery system was made and functional SPA was successfully confirmed as a new protein carrier.

• Journal of Pharmaceutical Investigation
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• v.36 no.2
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• pp.115-121
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• 2006

The aim of this study was to develop new protein/peptide depot system instead of poly(DL-lactic acid-coglycolic acid) (PLGA) microspheres. Pullulan was chemically modified by the addition of acetic anhydride (pullulan acetate; PA) and then investigated as new depot system for protein/peptide delivery. PA microspheres (PAM) with lysozyme as a model protein were prepared by w/o/w double emulsion method. The microspheres had a mean size of 10-50 mm with a spherical shape. The size distributions reduced with increasing the degree of acetylation. The loading efficiency of lysozyme was also increased. Lysozyme aggregation behavior in the microsphere was monitored to estimate the change of protein stability during preparation step. The ratios of protein aggregation in PAMs are lower than that of PLGA microsphere, in particular, PA 5 showed lowest as about 16%. The result indicated that the increase of acetylation suppressed the aggregation of protein. The release profiles of lysozyme from PAMs were significantly different. High acetylation effectively improved lysozyme release kinetics by reducing initial burst release and extending continuous release over a period of time. To check the effect of preservation for structural stability of lysozyme, the activity of lysozyme released from PA 5 was also observed. The activity of lysozyme was maintained almost 100% for 25 day. Therefore, PAM may become to a useful carrier for delivery of protein/peptide drugs, if it will be supported by biocompatibility and biodegradability results.

• Journal of Adhesion and Interface
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• v.16 no.2
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• pp.76-82
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• 2015

W/O emulsions were prepared from the aqueous solution containing NIPAAm, MBA, and APS in the continuous phase of toluene and mineral oil mixture with HMP and Span80 by using SPG membrane emulsification, and followed by the formation of PNIPAAm hydrogel microspheres through UV photopolymerization. As the ratio of mineral oil to toluene increased in the continuous phase, both particle size of the hydrogel increased and density of PNIPAAm polymer in the hydrogel particle increased, and which significantly affected swelling/deswelling ratio ($V/V_o$) with temperature change around VPTT. When the polymerization temperature was below LCST ($20^{\circ}C$), PNIPAAm hydrogel showed filled particle morphology; however, it was turned out to hollow particle morphology with thick shell layer with $40^{\circ}C$. Both density of PNIPAAm and gel content of the hydrogel increased with the increase in MBA concentration.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.1-21
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• 2011

This review describes several kinds of emulsification methods for nanoemulsions and the application of nanoemulsions. Nanoemulsion droplet sizes fall typically in the range of 20 ~200 nm and show narrow size distributions. Although most of the publications on either oil-in-water (O/W) or water-in-oil (W/O) nanoemulsions have reported their formation by dispersion or high-energy emulsification methods, an increased interest is observed in the study of nano-emulsion formation by condensation or low-energy emulsification methods based on the phase transitions that take place during the emulsification process. Phase behaviour studies have shown that the size of the droplets is governed by the surfactant phase structure (bicontinuous microemulsion or lamellar) at the inversion point induced by either temperature or composition. Studies on nanoemulsion formation by the phase inversion temperature (PIT) method have shown a relation between minimum droplet size and complete solubilization of the oil in a microemulsion bicontinuous phase independently of whether the initial phase equilibrium is single or multiphase. Due to their small droplet size nanoemulsions possess stability against sedimentation or creaming with Ostwald ripening forming the main mechanism of nanoemulsion breakdown. An application of nanoemulsions is the preparation of nanoparticles using a polymerizable monomer as the disperse phase where nanoemulsion droplets act as nanoreactors, cosmetics and controlled drug delivery. In this review, we mainly focus on the cosmetics.

• Journal of the Korean Applied Science and Technology
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• v.19 no.4
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• pp.291-296
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• 2002

Fatty polyamide that gives softness, lubrication and bulky property and alkyl imidazoline that gives durable softness and antistatic property were synthesized. then, an O/W-type durable softener (DSN) was prepared by the emulsion of the synthesized fatty polyamide and alkyl imidazoline. Emulsion stability of the DSN was good, and the mixed HLB value was 11.2. From the measurement of softness, lubrication, antistatic property, bending resistance, and color fastness, it was proved that the prepared DSN was a good durable softener for nylon.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.89-98
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• 2015

A synthesis method for a chitosan-coated magnetic drug-delivery system of cisplatin is proposed. Here, cisplatin was conjugated to the surface of Magnetite ($Fe_3O_4$) nanoparticles via a (3-Aminopropyl)-trimethoxysilane (APTS) coupling agent. To reduce the cytotoxic effect of cisplatin, the magnetic drug was then encapsulated in chitosan (CS-cisplatin-$Fe_3O_4$) through the water/oil (W/O) emulsion method. The CS-cisplatin-$Fe_3O_4$ nanoparticles were synthesized in a spherical shape with a diameter of 190 nm. The cytotoxicity assay was performed using HeLa cells. The cisplatin uptake of the cells was determined using High Performance Liquid Chromatography (HPLC) to calculate the drug content. The controlled release of cisplatin was demonstrated by regulating the dissolution and diffusion of the drug through the chitosan matrix.