• Clean Technology
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• v.23 no.3
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• pp.325-330
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• 2017

This study presents the preparation of n-tetradecane-in-water emulsions with different weight ratios of n-tetradecane and water, and their potential application in packaging and shipping vaccines. The size and distribution of the n-tetradecane droplets are characterized using optical microscopy and light scattering methods, respectively. The thermal properties of the emulsions are determined using the T-history method. In the results, the emulsions, which are comprised of 17 ~ 30 wt% oil, 3 wt% surfactant, and 67 ~ 80 wt% water, are stable and have droplet sizes in the range of 100 to 800 nm. The thermal properties demonstrate that subcooling is prevented through increasing the droplet size. The results indicate that the n-tetradecane/water emulsions containing 25 ~ 35 wt% n-tetradecane, with a melting point of $2{\sim}8^{\circ}C$ and a latent heat of $227.0{\sim}250.8kJ\;kg^{-1}$, are good candidate materials for packaging and shipping vaccines.

• Macromolecular Research
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• v.14 no.3
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• pp.359-364
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• 2006

Di-block copolymers composed of two biocompatible polymers, poly(ethylene glycol) and poly(D,L-lactide), were synthesized by ring-opening polymerization for preparing polymer vesicles (polymersomes). Emulsion solvent evaporation method was used to fabricate the polymersomes. Scanning electron microscope (SEM) images confirmed that polymersomes have a hollow structure inside. Confocal laser microscope and optical microscope were also used to verify the hollow structure of polymersomes. Polymersomes having various sizes from several hundred nanometers to a few micrometers were fabricated. The size of the polymersomes could be readily controlled by altering the relative hydrodynamic volume fraction ratio between hydrophilic and hydrophobic blocks in the copolymer structure, and by varying the fabrication methods. They showed greatly enhanced stability with increased molecular weight of PEG. They maintained their physical and chemical structural integrities after repeated cycles of centrifugation/re-dispersion, and even after treatment with surfactants.

• Journal of Pharmaceutical Investigation
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• v.28 no.1
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• pp.7-13
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• 1998

The captopril microcapsules were prepared and were investigated by measuring their size distribution using Scanning Electron Microscopy(SEM) and dissolution of captopril. Cetyl alcohol microcapsules prepared by emulsion melted-cooled method with various ratios of drug to cetyl alcohol were spherical and uniform. The release rate of cetyl alcohol microcapsules was decreased proportionally as the content of cetyl alcohol increased but, the particle size of microcapsules was increased. The surface of cetyl alcohol microcapsules was comparatively rough as drug content increased. Pellet type microcapsules were prepared using fluidized-bed coating system by spraying captopril solution on nonpareil-seeds followed by applying $Eudragit^{\circledR}$ RS solution containing propylene glycol as a plasticizer. The release rate of drug from pellet type microcapsules decreased as the content of $Eudragit^{\circledR}$ RS increased.

• Journal of Pharmaceutical Investigation
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• v.20 no.2
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• pp.55-64
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• 1990

Soybean fatty acid, the largest byproduct in the production of soybean oil, was formulated for hand cream, oil in water emulsion base, to improve the suppleness and elasticity of skin. The stability of emulsion observed by a macroscopic method was used as a characteristic index for deciding an optimum formula of hand creams. The optimum formula of the most stable hand cream was obtained from polynomial regression equation, contour graphs and partial derivative graphs. The values of soybean fatty acid and stearyl alcohol in the obtained optimum formula were 9.75 and 14.75 w/w%, respectively, and sodium lauryl sulfate was not needed. Experimental value for the stability of hand cream prepared according to the optimum formula was 76,14 days, and the prediction value by computation method was 73.25 days. From the results of accelerated tests by elevated temperature, the stability of hand cream by optimum formula was 1.7 year at room temperature $(25^{\circ}C)$. The hand cream containing soybean fatty acid was found to be free of primary irritant substance to the skin by Draize technique.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.696-700
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• 2008

The objective of this study was to investigate the genotoxicological safety and biological functions of octadeca-9,12-dienyl-3,4,5-trihydroxybenzoate (GA-LA) in cream-based emulsion for future application as a functional cosmetic material as well as food. GA-LA was synthesized chemically from gallic acid and linoleic acid. The Ames test showed that GA-LA did not have mutagenical toxicity. The control cream-based emulsion containing GA-LA was prepared by commercial method and tested for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Ferric reducing antioxidant power (FRAP) and inhibition effect against tyrosinase of the emulsions were tested for the evaluation of antioxidative and skin-whitening activities. The results showed that DPPH radical scavenging activity in the cream-based emulsion containing GA-LA was higher (52.65%) than that of the control (4.30%). The FRAP value of the sample was 12.85%, however, no activity was found in control. The inhibition effect of tyrosinase showed also a higher value (26.29%) when compared to the control. The results indicate that GA-LA, which showed superior antioxidative and skin-whitening activities in cream-based emulsion, is a useful functional material applicable in cosmetic products as well as food.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.220-227
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• 2012

The objective of this study was to investigate the influence of emulsion processing with various homogenization treatments on the physical properties of nanoparticles. For the manufacturing of nanoparticles, by taking the emulsion-diffusion method, various coating materials, such as gum arabic, hydroxyethyl starch, polycarprolactone, paraffin wax, ${\kappa}$-carrageenan and emulsifiers like Tween$^{(R)}$60, Tween$^{(R)}$80, monoglyceride and Pluronic$^{(R)}$F68, were added into the emulsion system. Furthermore, the various speeds (7,000 rpm to 10,000 rpm), and times (15 s to 60 s) of homogenization were treated during the emulsion- diffusion process. NEO II homomixer was the most effective homogenizer for making nanoparticles as 51 nm ($D_{10}$) and 26 nm ($D_{50}$). To manufacture smaller nanoparticles, by using NEO II homomixer, 10,000 rpm of agitation speed, polycaprolactone as coating material, and Pluronic$^{(R)}$F68 as an emulsifier were the optimum operating conditions and components. For the stability of nanoparticles for 7 days, $20^{\circ}C$ of storage temperature was appropriate to maintain the particle size. From these results, the type of homogenizer, homogenization speed, homogenization time and storage temperature could affect the particle size. Moreover, type of coating materials and emulsifier also influenced the size and stability of the nanoparticles.

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.24-31
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• 2004

A cold mix asphalt (CMA) treatment process was proposed as a tool to recycle soils contaminated with petroleum hydrocarbons. Experimental studies were conducted to characterize performances of the CMA process in treating soils contaminated with diesel or diesel compounds. From the screening experiments, it was found that performances of five types of asphalt emulsions that contained a cationic or an anionic or a nonionic surfactant were not substantially different. In consideration of higher affinity for soils and higher sorption coefficients obtained, an emulsion containing Lauryl Dimethyl Benzyl Ammonium Chloride (LDBAC) was selected as a promising asphalt emulsion for treating diesel-contaminated soils. When the asphalt emulsion LDBAC was applied to treat three compounds that originated from diesel, the removal efficiencies obtained in the order of decreasing efficiencies were as follows: docosane > pentadecane > undecane. Leaching experiments on the specimen formulated by the emulsion LDBAC found that the selected treatment method could treat soils with diesel concentrations as high as 10,000 mg/kg. Leaching of the diesel from the specimen was controlled by diffusion for the first four days and then leaching rate diminished substantially. The latter behavior was characterized as depletion, which represents that the contaminant released amounts to more than $50\%$ of the total amount of the contaminant that can be leached. The amounts of three diesel compounds leached from the specimen in the order of decreasing amount were undecane, pentadecane, and docosane. The curing of the soil contaminated with pentadecane was relatively slow.

• Journal of the Korean Applied Science and Technology
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• v.32 no.4
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• pp.731-739
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• 2015

We conducted this study to investigate possibilities of applying cosmetic material about extrats from Sparassis crispa. The extracts of Sparassis crispa conducted a antibacterial activity against Straphylococcus epidermidis, Straphylococcus aureus, Escheri chia coli, Candida albicans by the paper disc method and antioxidative effect and Nitric oxide production inhibitory activity were performed in Raw 264.7 cells. Also, we evaluated of pH, viscosity, particle observation stability of emulsion that are applied of extracts from Sparassis crispa. The antimicrobial activity showed by the paper disc method against Straphylococcus aureus, Candida albicans. The physical stability were stable of pH, viscosity in emulsion included extracts from Sparassis crispa. Emulsion containing Sparassis crispa extracts did not change particles into optical microscope. These results suggest that extracts from Sparassis crispa may have value as the potential cosmetic formulations.

• Journal of Dairy Science and Biotechnology
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• v.23 no.2
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• pp.115-123
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• 2005

Microcapsules consisting of natural, biodegradable polymers for controlled and/or sustained core release applications are needed. Physicochemical properties of whey proteins suggest that they may be suitable wall materials in developing such microcapsules. The objectives of the research were to develop water-insoluble, whey protein-based microcapsules containing a model water-soluble drug using a chemical cross-linking agent, glutaraldehyde, and to investigate core release from these capsules at simulated physiological conditions. A model water soluble drug, theophylline, was suspended in whey protein isolate (WPI) solution. The suspension was dispersed in a mixture of dichloromethane and hexane containing 1% biomedical polyurethane. Protein matrices were cross-linked with 7.5-30 ml of glutaraldehyde-saturated toluene (GAST) for 1-3 hr. Microcapsules were harvested, washed, dried and analyzed for core retention, microstructure, and core release in enzyme-free simulated gastric fluid (SGF) and simulated intestinal fluid(SIF) at $37^{\circ}C$. A method consisting of double emulsification and heat gelation was also developed to prepare water-insoluble, whey protein-based microcapsules containing anhydrous milkfat (AMF) as a model apolar core. AMF was emulsified into WPI solution (15${\sim}$30%, pH 4.5-7.2) at a proportion of 25${\sim}$50%(w/w, on dry basis). The oil-in-water emulsion was then added and dispersed into corn oil ($50^{\circ}C$) to form an O/W/O double emulsion and then heated at $85^{\circ}C$ for 20 min for gelation of whey protein wall matrix. Effects of emulsion composition and pH on core retention, microstructure, and water-solubility of microcapsules were determined. Overall results suggest that whey proteins can be used in developing microcapsules for controlled and sustained core release applications.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.181-189
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• 2017

Purpose: This study was conducted to examine the effects of the starch concentration of filled hydrogel and the addition of ${\alpha}-amylase$ and simulated mastication processing in an oral phase on lipid digestion and ${\beta}-carotene$ bioaccessibility of filled hydrogels. Methods: Lipid digestion and ${\beta}-carotene$ bioaccessibility of the filled hydrogels were measured after the samples were passed through an in vitro gastrointestinal tract model consisting of oral, gastric, and small intestinal phases. Results: The initial rate and final extent of lipid digestion were higher in the filled hydrogels than in the emulsion when the filled hydrogels were treated in an oral phase without simulated mastication processing and addition of ${\alpha}-amylase$, regardless of starch concentration. However, when the filled hydrogels were minced using mortar and pestle for 2 min and were exposed to ${\alpha}-amylase$, the filled hydrogel fabricated with 5% starch showed the lowest lipid digestion rate and extent compared to the emulsion and other filled hydrogels. Bioaccessibility of ${\beta}-carotene$ was higher in the filled hydrogels than in the emulsion, regardless of the digestion method performed in an oral phase and starch concentration. However, there were appreciable differences in bioaccessibility of the filled hydrogels depending on whether or not simulated mastication and addition of ${\alpha}-amylase$ were employed. Conclusion: These results suggested that the rheological properties of initial filled hydrogels and simulated mastication processing in an oral phase plays an important role in determining the lipid digestion and ${\beta}-carotene$ bioacccessibility entrapped within filled hydrogels.