• Investigative Magnetic Resonance Imaging
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• 제19권2호
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• pp.127-130
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• 2015

Direct injection of foreign material, such as liquid paraffin and silicone, into the breast can induce a foreign body granulomatous reaction and fibrosis, resulting in hard, nodular breast masses and architectural distortion that can mimic neoplasm. Conventional methods, including physical examination, mammography, and ultrasonography are of little use to differentiate between foreign body-induced mastopathy and breast cancer. In patients with foreign body injection such as breast augmentation, dynamic contrast enhanced MR imaging is an excellent imaging modality. Here, the authors report the MR imaging and pathological findings of ductal carcinoma in situ (DCIS) with multicystic changes in a 41-year-old woman with a previous history of interstitial mammoplasty by paraffin injection.

• Elastomers and Composites
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• 제23권1호
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• pp.11-17
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• 1988

The transport of chromium(VI) ion from waste water through the liquid surfactant membrane containing tri-n-octylamine as a carrier, was analyzed by a slab model and was investigated through experiments. For the experiment of membrane stability, concentrations of surfactant and liquid paraffin oil were analyzed. Extraction experiments were carried out to observe the effect of system variables, such as concentrations of carrier, and initial chromium(VI) ion in external aqueous phase at $25^{\circ}C$. It is concluded that the most stable formation of liquid membrane emulsion was obtained when surfactant concentration is above 3 wt.% and liquid paraffin oil concentration is 50 vol.%. The theoretical equation on the transport of chromium(VI) ion agreed well with the experimental results.

• 대한기계학회논문집B
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• 제22권6호
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• pp.888-898
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• 1998

The present study investigated the effects of the experimental parameters on the cooling characteristics of the multichip module cooled by the indirect liquid cooling method using water and paraffin slurry. The experimental parameters are mass fraction of 2.5 ~ 7.5% for paraffin slurry, heat flux of 10 ~ 40 W/cm$^{2}$ for the simulated VLSI chips and Reynolds numbers of 5,300 ~ 15,900. The apparatus consisted of test section, paraffin slurry maker, pump, constant temperature baths, flowmeter, etc. The test section made of in-line, four-row array of 12 heat sources for simulating 4 * 3 multichip module which was flush mounted on the top wall of a horizontal rectangular channel with the aspect ratio of 0.2. The inlet temperature was 20 deg. C for all experiments. The size of paraffin slurry was constant as 10 ~ 40 .mu.m befor and after the experiment. The chip surface temperatures for paraffin slurry with the mass fraction of 7.5% showed lower by 16 deg. C than those for water when the heat flux is 40 W/cm$^{2}$. The local heat transfer coefficients for the paraffin slurry with the mass fraction of 7.5% were larger by 17 ~ 25% than those for water at the first and the fourth row. The local heat transfer coefficients reached to a row-number-independent, thermally fully developed value approximately after the third row. The local Nusselt numbers at the fourth row for paraffin slurry with the mass fraction of 7.5% were larger by 23 ~ 29% than those for water.

• 기계저널
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• 제16권2호
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• pp.116-121
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• 1976

Non-steady hot wire method was adopted to measure thermal coductivity of paraffin wax in the phases of liquid and solid for the utilization of thermal energy storage. The instrument was tested with the measurement of thermal conductivity of water at various temperatures. The reproducibility of the instrumetn was found to be ${\pm}2%$, in which the results for water agree with the literature values. The thermal conductivity of paraffin wax varies from 0.177 W/m C to 0.236 W/m C when the phase changes from liquid to solid near the melting temperature.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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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 Pharmaceutical Investigation
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• 제18권4호
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• pp.175-180
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• 1988

The role and effect of aluminum tristearate in microencapsulation were investigated based on the dispersion system of ethambutol hydrochloride in acetone-liquid paraffin. Eudragit RS was used as a wall-forming material. Eudragit RS microcapsules prepared using aluminum tristearate were uniform, free-flowing particles. The phase diagram of ethambutol hydrochloride-Eudragit RS-aluminum tristearate indicated that spherical microcapsules ranging from 250 to 1400 ${\mu}m$ in diameter could be prepared only in a very limited region. Instrumental analysis using an energy dispersive-type X-ray microanalyser and a scanning electron microscope showed that aluminum tristearate was localized near the surface of microcapsules. From these results, it was presumed that aluminum tristearate reduced the phase tension between Eudragit microcapsules and liquid paraffin. The dissolution rates of ethambutol hydrochloride from Eudragit RS microcapsules were consideraly lower than those from ethambutol hydrochloride powders and decreased as the amount of aluminum tristearate decreased.

• 약학회지
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• 제33권5호
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• pp.312-318
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• 1989

Microcapsule of Propranolol HCl with Cellulose Acetate Phthalate (CAP) by coacervation-phase separation method was studied. Encapsulation was carried out in the CAP-liquid paraffin-acetone ethanol solvent system. The optimum weight ratio for microencapsulation in the CAP-liquid paraffin-solvent system was 1.32:89.18:9.50 or 1.65:89.42:8.93. The wall thickness of microcapsules increased according to increasing of CAP concentration, but dissolution rate decreased. The dissolution of propranolol-HCl in simulated gastric and intestinal fluid test solution was completed within 3 min., but T50% of propranolol HCl from 10.0% CAP-microcapsules were 390 min. and 210 min. respectively. The released amount from 12.5% CAP-microcapsules was 41.8% within 720 min. in simulatd gastric fluid test solution and T50% of those in simulated intestinal fluid test solution was 250 min.

• 대한화장품학회지
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• 제40권2호
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• pp.133-139
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• 2014

물/Span 80-Tween 80/긴 사슬 파라핀 오일 계에서 PIC (조성 상전이) 방법을 이용하여 O/W 나노에멀젼을 제조하였다. 제조 온도를 $30^{\circ}C$에서 $80^{\circ}C$로 상승시킴에 따라 제조된 나노에멀젼의 입경은 120 nm에서 40 nm로 감소하여 나노에멀젼을 형성하였다. 혼합 계면활성제의 HLB를 변화시킴에 따라 12.0 ~ 13.0 부근에서 가장 작은 입경을 형성하는 최적 HLB가 존재하였다. 나노에멀젼의 점도는 액적의 부피 분율(${\phi}$)에 따라 현격하게 증가하였으나, 입경의 크기는 약간 증가하였다. 그리고, ${\phi}{\leq}0.3$ 조건에서 나노에멀젼의 크기 분포는 2개월 이상 일정하게 유지 되었다. 이러한 결과는 점성 파라핀 오일의 경우 $30^{\circ}C$에서는 PIC 방식으로 거의 분산할 수 없음을 보여주지만, 제조 온도가 증가할 경우 단 분산 나노에멀젼의 제조가 가능하다는 것을 보여준다. 나노에멀젼이 생성되면, Ostwald ripening에 대한 안정성은 연속 상에서 액상 파라핀 오일의 매우 낮은 용해도로 인해 안정하게 되며, 이는 화장품 응용에서 매우 중요하다.

• 대한화장품학회지
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• 제21권2호
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• pp.22-48
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• 1995

본 연구에서는 ME의 각 성분의 구조가 그들의 생성영역, 입자의 크기 및 안정성에 미치는 영향을 고찰하고자 surfactant로서 POE sorbitan fatty acid 계를 사용하였고, oil로는 포화탄화수소계인 liquid paraffin, squalane, 방향족계열인 alkyl benzoate, Isostearyl benzoate를 그리고 cosurfactant로는 glycerine, propylene glycol, sorbitol, 1, 3-butanediol을 사용하여 4성분계 ME을 제조하고, 이 계에서 cosurfactant의 구조적 특성이 ME 생성영역에 미치는 영향과 그리고 oil과 surfactant의 구조 특성이 제조된 ME 입자크기 및 안정성에 미치는 영향을 고찰한 결과, cosurfactant로 polyol류를 사용했을 때, polyol 분자 중 탄소가 같은 경우 OH수가 많을 때, OH기 수가 같을 경우 탄소수가 적을 때 ME생성영역이 크게 나타남을 알 수 있었으며 제조된 ME의 입자 크기를 비교했을 때 oil의 극성이 클수록, surfactant 소수부분의 alkyl chain의 탄소수가 클수록 입자크기가 작게 나타났다. 또한 분산상으로 사용된 oil 중 alkyl benzoate나 Isostearyl benzoatbenzoate 에 비해서 포화탄수소계인 liquid paraffin, squalane으로 구성된 ME의 경시 안정성이 더 양호하였다.

• 태양에너지
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• 제11권2호
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• pp.51-62
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• 1991

본 연구에서는 용융된 파라핀을 채운 수평 원관의 관벽을 냉각할 때에 관내에서 일어나는 열전달현상을 다루었다. 관내의 파라핀을 고상과 액상으로 구분하여 고상층에 대해서는 열전도 모델을, 그리고 액상층에 대해서는 자연대류를 고려한 열전달모델을 세워 수치해석하였고 이 과정에 대한 실험을 행하여 얻은 응고형태로부터 방열량을 계산하였다. 아울러 초기의 용융파라핀의 온도와 관벽의 냉각온도가 응고에 미치는 영향을 고찰하였다. 방열과정에서 액상파라핀의 응고속도를 결정하는 요인은 관벽의 냉각온도와 초기액상온도이나 대부분의 액상현열이 응고 초기에 급속히 방출되기 때문에 관벽의 냉각온도가 지배적인 요인으로 작용하였다. 따라서 방열과정에서의 열전달은 고상층 내의 열전도에 의해서 이루어지게 된다. 실험에서 관찰한 응고형태에서는 상부에 빈 공간이 발견되었다. 이는 초기 액상온도가 응고초기에 급속히 떨어짐으로써 온도에 따른 액상의 밀도차로 인해 생긴 것이다. 고 액간의 밀도차로 인한 수축현상은 응고과정의 전반에 걸쳐서 고르게 일어나므로 그 영향을 응고형태에서 구별하여 파악하기는 어려웠다. Fourier수와 고상의 Stefan수를 종속변수로 사용하면 관벽의 냉각온도와 초기액상온도에 무관하게 응고량을 단일곡선으로 표현할 수 있었다.