• Applied Microscopy
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• 제45권4호
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• pp.249-253
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• 2015

Microorganisms specifically groups of bacteria exhibiting physiological activities of production of acids are a major cause of concern because of their ability to induce corrosion in oil field pipelines and metal systems involved in water handling. Water Injection Stations as a means of secondary recovery from existing oil producing reservoirs, are often employed in most upstream oil and gas industries to ensure replenishment of voidage, maintenance of reservoir pressure and optimization of crude emulsion throughput. In the present study, scanning electron microscopy of macroscopic orange coloured slime formations sampled from leaking valves on the flow-lines of a Water Injection Stations of Oil India Limited revealed the presence of filamentous bacterial mats in association with diatoms. The species composition of the acidic slime formations from the sampled locations reveal the possible role of acid producing iron oxidizing bacteria (IOB) like Acidithiobacillus ferrooxidans in association with Gomphonema sp. in creating conditions for bio-corrosion.

• 대한화장품학회지
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• 제24권3호
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• pp.129-133
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• 1998

We have studied a relationship between the pattern of complex modulus change versus internal phase volume ratio and the rheological consistency of concentrated W/O emulsions with Magnesium Sulfate in the range 0.0 to 0.5 wt% and with different oil polarities, respectively. The rheological consistency with time of concentrated W/O emulsion was checked using Fudoh Rheometer and the coalescence of deformed water droplets was examined using polarized light microscope(LEICA DMRP). To find the pattern of complex modulus change of the concentrated emulsions versus internal phase volume ratio, the effect of varying water phase volume fraction from 0.78 up to 0.85 on viscoelastic measurements was investigated using rotational rheometer (HAAKE Rheostress RS 50). The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The greater the increase of complex modulus was, the less coalescence occurred and the more consistent the concentrated emulsions were. And the pattern of complex modulus increase versus volume ratio has been explained with the resistance to coalescence of the deformed interfacial film of water droplets in concentrated W/O emulsion.

• Archives of Pharmacal Research
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• 제9권3호
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• pp.145-152
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• 1986

Magnetically reponsive gelatin microspheres for the targeting of drugs have been prepared using a water-in-oil emulsion technique with chemical cross-linking of the protein. The manufacturing variables affecting microsphere size, size distribution and surface characteristics have been examined as well as the magnetic responsiveness in vitro. Sesame oil was utilized for non-aqueous phase and magentic gelatin microspheres of different size from 1. 89 to 14.88 $\mu\textrm{m}$ in mean diameter could be obtained with variation of HLB values of non-ionic surfactants. The content of magnetite which uniformly distributed throughout the microspheres was 26.7% (w/w). It was possible to control the localization of magnetic gelatin microspheres at specific sites within capilary models by using external magnetic field of under 5K gauss.

• 한국축산식품학회지
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• 제40권3호
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• pp.426-443
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• 2020

In order to investigate the use of oil in water gelled emulsion (GE) prepared with healthier oil combinations as beef fat replacer in the fresh chicken sausage formulations, four batches of fresh sausages were produced. The first batch was control (C) sample formulated with %100 beef fat, other batches were codded as GE50, GE75, and GE100 respective to the percentage of beef fat replaced with GE. The addition of GE to sausage formulation resulted in an increment in moisture and protein contents while a decrement was observed in fat content (p<0.05). pH, cooking yield and water holding capacity values of GE added samples were found lower than C (p<0.05). GE addition caused lower CIE L* values in samples, however, this trend was not observed in CIE a* and CIE b* values. Initially, the lowest peroxide and the highest TBARS values were recorded in GE100 samples on the 0^th d (p<0.05). Peroxide and TBARS values were in the limits. The texture of samples was softened while total saturated fatty acid content reduced up to 52.61% with the incorporation of GE (p<0.05). Taken together, our results showed that GEs can be used as fat replacers in meat product formulations without causing undesirable quality changes.

• Food Science and Biotechnology
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• 제18권1호
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• pp.157-161
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• 2009

Resveratrol-loaded poly($\varepsilon$-caprolactone) (PCL) nanoparticles were prepared by oil in water (O/W) emulsion solvent evaporation method. The morphology of the nanoparticles was evaluated using atomic force microscope (AFM), in which well-shaped and rigid nanoparticles were prepared. The mean particle size of nanoparticles prepared using only dichloromethane (DCM) ($523.5{\pm}36.7\;nm$) was larger than that prepared with a mixture of DCM and either ethanol (EtOH) ($494.5{\pm}29.2\;nm$) or acetone ($493.5{\pm}6.9\;nm$). The encapsulation efficiency of nanoparticles prepared only with DCM as dispersed phase ($78.3{\pm}7.7%$) was the highest of those prepared with solvent mixtures. An increase in the molecular weight of PCL led to an increase in encapsulation efficiency (from $78.3{\pm}7.7$ to $91.4{\pm}3.2%$). Pluronic F-127 produced the smallest mean size ($523.5{\pm}36.7\;nm$) with the narrowest particle size distribution. These results show that dispersed phase, molecular weight of wall materials, emulsion stabilizer could be important factors to affect the properties of nanoparticles.

• 대한화장품학회지
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• 제43권4호
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• pp.273-279
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• 2017

본 실험에서는 화장품에 널리 사용되는 지방산과 지방알코올을 Tween 80과 Span 80을 함께 사용하여 조성 상전이 유화법으로 O/W (oil-in-water) 저점도 나노에멀젼을 제조하였다. 지방알코올의 오일상에서의 농도가 증가할수록 나노에멀젼의 입자 크기가 증가하였다. 혼합계면활성제의 HLB를 조절하여 입도 분포가 좁고 안정한 나노에멀젼의 제조가 가능하였다. 전상점 부근에서 지방산 및 지방알코올을 함유한 계 모두에서 유사한 점도와 전기전도도의 변화를 보였으나 오일과 계면활성제만으로 구성된 계와는 다르게 넓은 수용액상 분율범위에서 높은 점도를 나타냈다. 입자 크기가 100 nm 미만의 저점도 나노에멀젼은 실온에서 한 달 이상 안정하였다. 지방산 또는 지방알코올을 함유하고, 저에너지 유화법으로 제조된 저점도 O/W 나노에멀젼 제형은 화장품의 기재로서 널리 사용될 수 있다.

• 한국식품영양과학회지
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• 제28권4호
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• pp.890-894
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• 1999

Microencapsulation of anchovy oil as a core material in sodium alginate as a wall material was inves tigated. Microencapsulation was accomplished by injecting an oil/water emulsion, consisting of a mixture of liquefied sodium alginate and emulsifier, under high pressure through an orifice submerged in a calcium lactate solution. Microcapsules suspended in a dispersion fluid were observed under a fluorescence mi croscope to verify the presence of the capsules and to note coalescence or degradation of the capsules. Optimum conditions for microencapsulation of anchovy oil were obtained when 1.0% aqueous solution of sodium alginate contained 3% of a 1:1 ratio of ESPR 25(polyglycerine＋polylinoleate) and TW 20(sorbitan laurate＋ethylene oxide) as an emulsifier in terms of capsule size and size distribution, and emulsion stability. The airless sprayer produced microcapsules with a diameter between 15.9 and 73.9 m with different concentration of a wall material. The optimum mixing ratio of wall material to core material was 90:10(wt/wt). 0.2% calcium lactate was appropriate as a dispersion fluid.

• 미생물학회지
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• 제34권3호
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• pp.162-168
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• 1998

기름-물 유상액의 탈유화능이 있는 Streptomyces sp. 8321을 분리하여 이의 탈유화 특성을 조사하였다. 이 방선균의 탈유화능은 포자에 기인하였으며, 배양기간에 따라 포자표면의 소수성이 증가하였고, 이에 따라 탈유화능이 증가함을 보였다. 8일간 고체배지에서 배양한 Streptomyces sp. 8321의 포자용액이 kerosene-0.2% Triton X-100(2:1) 표준 유상액 3 ml을 완전 탈유화 시키는 농도는 $1.1{\times}10^8spores/ml$였다. 이 포자용액의 탈유화능을 유기상 종류 및 유화제 종류에 따라 조사해본 결과, 저점성의 유기상에서는 n-hexadecane 및 diesel 등 탄소수가 높은 것이 쉽게 탈유화 되었고, 고점성 유상액의 탈유화는 24시간 후에도 20-30%만이 일어났다. Corexit, Finalsol, BP series의 유화제와 kerosene으로 이루어진 O/W 유상액은 1분 이내에 완전 탈유화가 일어났으며, Corexit 7664, 8667, Triton X-100 및 Tween 80으로 이루어진 O/W 유상액은 이들 유화제의 농도가 증가함에 따라 탈유와 속도가 감소하였다. Seagreen으로 이루어진 W/O 유상액의 경우 $t_{1/2}$이 24시간 이상으로 나타나 이 균주의 탈유화능은 O/W 유상액에 효과적임을 보여주었다.

• Membrane and Water Treatment
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• 제6권3호
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• pp.237-249
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• 2015

In this study we investigate a laboratory scale vacuum membrane distillation system to produce pure water from model oil in water emulsion. Experimental determination of liquid entry pressure (LEP) of a commercial Durapore$^{TM}$ GVPH flat sheet membrane using model emulsions in various oil concentrations has been carried out. Two different methods of liquid entry pressure determination - a frequently used, so-called static and a novel dynamic method - have been investigated. In case of static method, LEP value was found to be 2.3 bar. No significant effect of oil content on LEP was detected up to 3200 ppm. In contrast, LEP values determined with dynamic method showed strong dependence on the oil concentration of the feed and decreased from 2.0 bar to a spontaneous wetting at 0.2 bar in the range 0-250 ppm, respectively. Vacuum membrane distillation tests were also performed. The separation performance is evaluated in terms of flux behavior, total organic carbon removal and droplet size distribution of the feed and final retentate. No significant effect of oil content on the flux was found ($5.05{\pm}0.31kgm^{-2}h^{-1}$) up to 250 ppm, where a spontaneous wetting occurred. High separation performance was achieved along with the increasing oil concentration between 93.4-97.0%.

• 한국응용과학기술학회지
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• 제21권1호
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• pp.31-36
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• 2004

Liquid crystalline phases were formed from acylglutamate; polyglyceryl-10 myristate and glycerine mixture and they were used as a base material for preparing an O/W emulsion. When an oil phase is added into the liquid crystalline phases, it was inserted into the dispersed liquid crystal droplets rather than stayed outside the liquid crystals, which can be known by the fact that the size of liquid crystal droplets increases with the increasing oil phase content. Along with the increase in the droplet size, the complex modulus increases from 100 to 350 pascals and the loss angle decreases from 60 to 24 degrees, from which it can be known that the increase in the internal phase volume results in the increase in the elastic property of oil in liquid crystalline-phases (O/LC). When the water phase was lastly added into the O/LC phase, the emulsification occurred to form a O/W emulsion and the averaged particle size of the O/W emulsion changes from 22.5nm to 538nm with the addition of water phase. The results from the droplet size measurements and stability tests under accelerated conditions such as high temperature show that the obtained O/W emulsion is very consistent with time.