• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.219-230
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• 1974

For the production of single cell protein from n-paraffin, yeasts utilizing n-paraffin and ethanol were isolated from oil deposit and oil field soils. The mixed cultivation between yeasts assimilating n-paraffin and ethanol was carried out to increase cell yield. Finally, selected strains were identified and suitable medium composition for mixed culture was compared with that of single cultures using flask and 5 l-jar fermentor. Yeasts grow on n-paraffin and ethanol were identified as Candida tropicalis var. KIST 76 and Trichosporon cutaneum KIST 76H respectively. By mixed cultivation under the suitable medium composition using 5 l-jar fermentor, maximum dry cell weight reached 20 g/l after 12 hrs. cultivation and it's protein content was 58%. Yield has been increased about 25% and protein content has been increased 6.7% compared to that of single culture, Candida tropicalis var. KIST 76, after 16 hrs. cultivation.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.821-824
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• 2009

In this study, a hydrogenated lecithin-containing nanoemulsion was prepared from hydrogenated lecithin and silicone oil. Tween-60 and liquid paraffin, widely known emulsifiers, were used as standard substances, and high shear was produced by utilizing a high shear homogenizer and microfluidizer. The properties of the nanoemulsion prepared with hydrogenated lecithin were evaluated by measuring interfacial tension, dynamic interfacial tension, droplet size, zeta-potential, friction force, skin surface hygrometery, and dermal safety. The interfacial tension of lecinol S10/silicone oil was lower than that of lecinol S10/liquid paraffin. The nanoemulsion prepared from hydrogenated lecithin shows lower zeta-potential, skin surface hygrometery, and friction force compared with a general emulsion. The silicone nanoemulsion prepared from hydrogenated lecithin showed a zero value in the patch test and thus exhibits high dermal safety.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.2
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• pp.231-239
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• 1999

The microstructure of ceramic composite has been found to be governed by the type and amount of the secondary phase, the sintering aid, and the sintering conditions such as sintering temperature, pressure and holing time. Moreover, tribological properties are strongly dependent on microsturcture of composite and operating conditions. In this study, silicon nitride with various amount of magnesia as a sintering aid were prepared and sintered by a hot pressing (HP) technique. Microstructure, mechanical properties (hardness, strength, and fracture toughness), and tribological properties in different environments of $Si_{3}N_{4}$ (in air, water, and paraffine oil) were investigated as a function of MgO content in $Si_{3}N_{4}$. As increasing the amount of MgO in $Si_{3}N_{4}$, the glassy phase in the grain boundaries enlarged the $\beta$-phase elongated grains, and also degraded the Hertzian contact damage resistance. Tribological behaviors in air was seemed to be determined by fracture toughness of $Si_{3}N_{4}$, and those in water and paraffin oil was seemed to be determined by hardness as well as strength. Since glassy grain-boundary phase (MgO) in $Si_{3}N_{4}$ expected to be reacted with water during sliding, such tribochemical reaction reduced wear. In paraffin oil under a higher applied load, the initial sliding dominated wear rate because of Hertzian contact damage.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.133-139
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• 2014

Oil-in-water nanoemulsions were prepared in the system of water/Span 80-Tween 80/long-chain paraffin oil via the PIC (phase inversion composition) method. With the increase of preparation temperature from $30^{\circ}C$ to $80^{\circ}C$, the diameter of emulsion droplets decreased from 120 nm to 40 nm, proving the formation of nanoemulsions. By varying the HLB (hydrophilic lipophilic balance) of mixed surfactants, we found that there was an optimum HLB around 12.0 ~ 13.0 corresponding to the minimum droplet size. The viscosity of nanoemulsions clearly increased with droplet volume fraction, f, but the droplet size slightly increased. Significantly, at ${\phi}{\leq}0.3$, the size distribution of nanoemulsions kept constant more than 2 months. These results proved that the viscous paraffin oil can hardly be dispersed by the PIC method at $30^{\circ}C$, but the increase in preparation temperature makes it possible for producing monodisperse nanoemulsions. Once the nanoemulsion is produced, the stability against Ostwald ripening is outstanding due to the extremely low solubility of the liquid paraffin oil in the continuous phase. The highly stable nanoemulsions are of great importance in cosmetic applications.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.10 no.1
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• pp.8-12
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• 1984

Increasing the oil volume in the oil : water mixtures using isopropyl myristate, oleic acid as oils, the solubilities of methyl, propyl and butyl parabens and the MICs (minimum hibitory concentrations) to E. coli were increased. But in liquid paraffin, the solubility was reversed. The relation between MIC and solubility of parabens had constant factor of 0.7 as saturation fraction percent. The solubility of methyl paraben was crossed over in those of propyl and butyl parabens, when the oil volume was increased. When the oil was used over the cross-over point, methyl paraven was useful to preserve the systems, and below the cross-over point the more lipophilic propyl and/or butyl parabens were effective.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.155-159
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• 2019

As a part of improving the quality for the fraction of the waste plastics pyrolysis oil (WPPO), the recovery of paraffin components contained in the fraction was investigated by dimethylformamide (DMF) equilibrium extraction. The fraction of a distilling temperature of $120{\sim}350^{\circ}C$ recovered from WPPO by the simple distillation and the aqueous solution of DMF were used as a raw material and solvent, respectively. The concentrations of paraffin components ($C_{12}$, $C_{14}$, $C_{16}$ and $C_{18}$) contained in the raffinate decreased by increasing the mass fraction of water in the solvent at an initial state ($y_{w,0}$), whereas, the concentrations of paraffin components contained in the raffinate increased by increasing the mass ratio of the solvent to the feed at an initial state $(S/F)_0$. The concentrations of $C_{12}$, $C_{14}$, $C_{16}$ and $C_{18}$ paraffin components present in the raffinate recovered at $(S/F)_0=10$ were about 1.37, 2.0, 2.46 and 3.16 times higher than those of the raw materials, respectively. Recovery rates (residue rates present in raffinate) of paraffin components rapidly increased with increasing $y_{w,0}$, and decreasing $(S/F)_0$. The raffinate recovered through this study was expected to be used as a renewable energy.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.370-370
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• 2006

Thermoplastic elastomer gels, which has molecular networks composed of a microphase-separated multiblock copolymer swollen to a large extent by a low volatility mid-block selective solvent such as white oil have various applications. In this particular study, the effect of several network-forming nanoscale fillers such as two different graphite particles and carbon nanotube on the properties of TPE gels prepared from a microphaseordered poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) triblock copolymer with an EB compatible white oil was studied. The linear viscoelastic behavior, sol-gel transition, x-ray diffraction and mechanical properties were discussed. The properties of thermoplastic elastomer gels hybrid with graphite prepared by mixing Poly(styrene-b-ethylene-co-butylene)-b-styrene) with paraffin oil and different amount of expandable graphite were found to increase the mechanical properties at only lower graphite concentration but tends to decrease when paraffin oil/SEBS ratio is lower. The gelation temperature is the same for all TPE gels with different amounts of graphite. Both storage (G') modulus loss (G") modulus of TPE gels slightly increase with addition of graphite.

• Membrane and Water Treatment
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• v.13 no.4
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• pp.201-208
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• 2022

Emulsion Liquid Membrane (ELM) is a prominent technique for the separation of heavy metal ions from wastewater due to the fast extraction and is a single-stage operation of stripping-extraction. The selection of the components (Surfactant and Carrier) of ELM is a very significant step for its preparation. In the ELM technique, the primary water- in-oil (W/O) emulsion is emulsified in water to produce water-in-oil-in-water (W/O/W) emulsion. The water in oil emulsion was prepared by mixing the membrane phase and internal phase. To prepare the membrane phase, the extractant D2EHPA (di-2-ethylhexylphosphoric acid) was used as a mobile carrier, Span-80 as a surfactant, and Paraffin as a diluent. Moreover, the internal (receiving) phase was prepared by dissolving sulphuric acid in water. Di-(2- ethylhexyl) phosphoric acid such as surfactant concentration, carrier concentration, sulphuric acid concentration in the receiving (internal) phase, agitation time (emulsion phase and feed phase), the volume ratio of the membrane phase to the receiving phase, the volume ratio of the external feed phase to the primary water-in-oil emulsion and pH of feed were studied on the percentage extraction of metal ions at 20℃. The results show that it is possible to remove 78% for As(V), 98% for Cd(II), and 99% for Pb(II). Emulsion Liquid Membrane (ELM) is a well-known technique for separating heavy metal ions from wastewater due to the fast extraction and is a single-stage operation of stripping-extraction. The selection of ELM components (Surfactant and Carrier) is a very significant step in its preparation. In the ELM technique, the primary water-in-oil (W/O) emulsion is emulsified to produce water-in-oil-in-water (W/O/W) emulsion. The water in the oil emulsion was prepared by mixing the membrane and internal phases. The extractant D2EHPA (di-2-ethylhexylphosphoric acid) was used as a mobile carrier, Span-80 as a surfactant, and Paraffin as a diluent. Moreover, the internal (receiving) phase was prepared by dissolving sulphuric acid in water. Di-(2-ethylhexyl) phosphoric acid such as surfactant concentration, carrier concentration, sulphuric acid concentration in the receiving (internal) phase, agitation time (emulsion phase and feed phase), the volume ratio of the membrane phase to the receiving phase, the volume ratio of the external feed phase to the primary water-in-oil emulsion and pH of feed were studied on the percentage extraction of metal ions at 20℃. The results show that it is possible to remove 78% for As(V), 98% for Cd(II), and 99% for Pb(II).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.1
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• pp.137-155
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• 1999

The o/w emulsions were prepared by lysolecithin as a biosurfactantsto to emulsify oils with squalane(SQ), liquid paraffin(LP), octylpalmitate(OP), octylstearate(OS), alkyl benzoate(AB), isostearyl benzoate(ISB). The droplets size and shape of o/w emulsions were investigated by laser light scattering, With dynamic light scattering hydrodynamic radius(Rh) of emulsion droplets was varied from 150m to 250m and critical concentration of oil In which the hydrodynamic radius(Rh) of emulsion droplets decreased and increased was found in the point of 0.5wt% oil concentration, and it was found increasing the polarity of oil deccreased the droplets, the droplets size of SQ(polar oil) were lower than SQ(nonpolar oil) With static light scattering radius of gyration(R$_{g}$) of emulusion droplets was to be calculated. From measurements of the ratio of R$_{g}$R$_{h}$ it was found that the shape of droplet of ISB, AB(polar oils) were sphere, for OP, OS(apolar oil) were oblate, for LP, SQ(nonpolar oil) were rod. The viscosity of emulsion in the form of rod was higher than that of emulsion in the form of sphere.e.e.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.384-388
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• 1988

A marine bacterium Achromobacter sp. M-1220 was isolated from enrichment culture for emulsification of Bunker-C oil. The bacterium can emulsify approximately 7.5g of Bunker-C oil per liter in sen water medium within 1 drys at 18$^{\circ}C$ and multiply from 8$\times$10$^5$ cells to 9$\times$10$^9$ cells per mi. Optimum pH and salt concentration were pH 7.5 and 3% for the emulsification of Bunker-C oil. Emulsification takes place actively in both high sulfur-containing Bunker-C oil and high sulfur-con-taming crude oil. The amount of emulsification depends on the exogenous addition of nitrogen and phosphate sources. The bacterium can also utilize n-hexndecane, n-paraffin me benzene among the petroleum compounds as a sole carbon source.