• 대한약리학회지
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• 제13권1호
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• pp.1-6
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• 1977

The physicochemical equivalencies of drugs are not usually correlate to the generic equivalencies of drugs and the generic equivalencies of drugs produced by different manufacturers or different formulations are being called in question frequently. The bioabailability of two formulations of oxytetracycline and erythromycin stearate were performed in healthy human volunteers. At the same time, the disintegration testes were performed with randomly sampled materials in question. For the biological evaluation of new oxytetracycline formulation; tablet(250mg), two-way cross over study in 10 healthy young volunteers was performed using oxytetracycline capsule (250mg) as reference, Erythromycin stearate (250mg) tablets and capsules produced by different manufacturers were compared in a two-way cross over study in 12 subjects with same manner of oxytetracyclines. oxytetracycline tablets showed somewhat slow disintegration rate, but appeared not statistical differences in serum concentrations from the reference, up to six hours after ingestion. Erythromycin stearate capsules disintegrated more rapidly than enteric coated tablets. Serum concentrations of capsules were more variable and markedly lower (P<.005 after 2hrs) than the enteric coated tablets. Rapid disintegration of capsules may result in destruction of active chemicals owing to the interaction with gastric acid and the above factor may contribute mainly to the low serum level after ingestion of capsules.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.675-678
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• 2001

Calcium stearate was produced by this method was purified and recovered through new method. Lipolase 100-T was used to produce calcium stearate from hydrogenated beef tallow. This process was optimized major factor of two, temperature and enzyme concentration. The temperature was optimized in $60^{\circ}C$ and enzyme concentration was 0.6wt% of hydrogenated beef tallow.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.601-603
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• 2000

Enzyme production of calcium stearate was attempted by lipase. Lipase having the highed hydrolyzing activity at $60^{\circ}C$, a melting point of substrate (hydrogenated beef tallow),was selected. 60% of hydrogenated beef tallow was converted into calcium stearate in 48hr. This result showed the possible replacement of conventional waste-producing process into enzymetic reaction.

• ETRI Journal
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• 제25권6호
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• pp.517-522
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• 2003

This investigation confirms that silver stearate consists of an infinite-sheet, two-dimensional, nonmolecular layered structure. Scanning electron microscopy, X-ray diffraction, and infrared spectroscopy reveal the following: plate-like morphology is identified from the SEM image, XRD peaks can be indexed to the (0k0) reflections of a layered structure, and infrared peaks show that alkyl chains are present in an all-trans conformational state with little or no significant gauche population. Based on these structural characteristics, we demonstrate that silver stearate, a prototype of layered organic-inorganic hybrid material, can be grown not only in a designed two-dimensional pattern but also in three-dimensionally ordered ways by using carboxyl-group terminated nanoparticles as a template.

• 공업화학
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• 제10권8호
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• pp.1216-1220
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• 1999

괴상 중합과 현탁 중합 및 수산화나트륨을 이용한 중화를 통하여 제조된 poly(styrene-co-sodium methacrylate) 이오노머의 가소제로 스테아린산 아연을 첨가하여 열적 성질과 유변학적 성질에 미치는 영향을 조사하였다. 이오노머 중 스테아린산 아연은 이온기 함량에 따라 부분적으로 결정화가 억제됨이 관찰되었다. 이오노머 중 이온기들은 스테아린산 아연을 용해시키고 결정화를 억제하는 것으로 판단되었으며, 이온기 1몰이 0.4~0.6몰의 스테아린산 아연을 용해시키는 것으로 추정할 수 있었다. 용해된 형태의 스테아린산 아연만을 포함한 이오노머는 Cox-Merz 플롯에서 전형적인 균일계의 유변학적 거동을 보였다. 그러나 용해된 스테아린산 아연뿐 아니라 결정성 스테아린산 아연을 포함한 이오노머들은 Cox-Merz 플롯에서 불균일계의유변학적 거동을 보였다.

• 대한화장품학회지
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• 제40권3호
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• pp.237-246
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• 2014

다중 에멀젼은 다층 구조를 갖는 에멀젼으로 W/O/W형과 O/W/O형으로 구분된다. 화장품 분야에서 다중 에멀젼은 불안정한 유효성분의 안정화를 위해 이용되지만, 제조의 어려움과 안정성 등의 문제로 잘 이용되지 않는다. 본 연구에서는 다중 에멀젼의 제조에 있어 2 단계(two-step) 유화법을 이용하여 W/O/W형 다중 에멀젼을 제조하였고, 다중 에멀젼의 형성에 영향을 주는 요소 중 유화제의 계열에 초점을 두어 유화 안정성 및 에멀젼 형성정도를 측정하였다. 결과를 통해 다중 에멀젼은 오일의 특성에 따라 polyglyceryl-10 stearate 유화제에 의해 다중 에멀젼의 형성이 달라지는 것을 확인하였고, 이를 통해 주 유화제로써 polyglyceryl-10 stearate 유화제의 적용이 다중 에멀젼 형성 및 안정화의 가능성이 있음을 제시하였다.

• BMB Reports
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• 제42권6호
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• pp.367-372
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• 2009

In this study, we showed that WAX9D, a nonspecific lipid-transfer protein found in broccoli, binds palmitate (C16) and stearate (C18) with dissociation constants of 0.56 ${\mu}M$ and 0.52 ${\mu}M$, respectively. WAX9D was fused to thioredoxin protein by genetic manipulation to enhance its solubility. The data revealed strong interaction of Trx-WAX9D with palmitate and stearate. The dissociation constants of Trx-WAX9D for palmitate and stearate were 1.1 ${\mu}M$ and 6.4 ${\mu}M$, respectively. The calculated number of binding sites for palmitate and stearate was 2.5 to 2.7, indicating that Trx-WAX9D can bind three molecules of fatty acids. Additionally, Trx-WAX9D was shown to inhibit the apoptotic effect of palmitate in endothelial cells. Our data using Trx-WAX9D provide insight into the broad spectrum of its biological applications with specific palmitate binding.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1165-1166
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• 2006

An experiment was carried out to investigate the effect of Ba Stearate as a reducing agent on the magnetic and physical properties of anisotropic $BaFe_2-W$ type ferrite magnets. It was found that the magnetic properties of $BaO{\cdot}8.5Fe_2O_3$ were improved by adding 0.3 wt% of Ba Stearate, 0.5 wt% of $SiO_2$, and 0.5 wt% of CaO together. The optimum conditions for making magnets were as follows; semisintering condition: $1350^{\circ}C{\times}4.0$ h in nitrogen gas atmosphere, drying condition: $180^{\circ}C{\times}2.0$ h in air, sintering condition: $1160^{\circ}C{\times}1.5$ h in nitrogen gas atmosphere. Magnetic and physical properties of a typical sample were $J_m$ = 0.46 T, $J_r$ = 0.43 T, $H_{cJ}$ = 182.3 kA/m, $H_{cB}$ = 177.2 kA/m, $(BH)_{max}$ = 33.8 kJ/$m^3$, $T_C$ = $495^{\circ}C$ and $K_A$ = $2.65{\times}10^5\;J/m^3$ and $H_A$ = 1332 kA/m.

• Macromolecular Research
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• 제17권10호
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• pp.776-784
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• 2009

N,N-dimethyldodecylamine (tertiary amine)-modified MMT (DDA-MMT) was prepared as an organically modified layered silicate (OLS), after which styrene-butadiene rubber (SBR) nanocomposites reinforced with the OLS were manufactured via the latex method. The layer distance of the OLS and the morphology of the nanocomposites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). By increasing the amount of N,N-dimethyldodecylamine (DDA) up to 2.5 g, the maximum values of torque, tensile strength and wear resistance of the SBR nanocomposites were increased due to the increased dispersion of the silicate layers in the rubber matrix and the increased crosslinking of the SBR nanocomposites by DDA itself. When SBR nanocomposites were manufactured by using the ternary filler system (carbon black/silica/OLS) to improve their dynamic properties as a tire tread compound, the tan $\delta$(at $0^{\circ}C$ and $60^{\circ}C$) property of the compounds was improved by using metal stearates instead of stearic acid. The mechanical properties and wear resistance were increased by direct substitution of calcium stearate for stearic acid because the filler-rubber interaction was increased by the strong ionic effect between the calcium cation and silicates with anionic surface. However, as the amount of calcium stearate was further increased above 0.5 phr, the mechanical properties and wear resistance were degraded due to the lubrication effect of the excessive amount of calcium stearate. Consequently, the SBR/organoclay nanocomposites that used carbon black, silica, and organoclay as their ternary filler system showed excellent dynamic properties, mechanical properties and wear resistance as a tire tread compound for passenger cars when 0.5 phr of calcium stearate was substituted for the conventionally used stearic acid.

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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• pp.414-421
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• 2014

This study was conducted to determine the effects of saturated long-chain fatty acids (LCFA) on cell proliferation and triacylglycerol (TAG) content, as well as mRNA expression of ${\alpha}s1$-casein (CSN1S1) and genes associated with lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows, and were passaged twice. Then cells were cultured with different levels of palmitate or stearate (0, 200, 300, 400, 500, and 600 ${\mu}M$) for 48 h and fetal bovine serum in the culture solution was replaced with fatty acid-free BSA (1 g/L). The results showed that cell proliferation tended to be increased quadratically with increasing addition of stearate. Treatments with palmitate or stearate induced an increase in TAG contents at 0 to 600 ${\mu}M$ in a concentration-dependent manner, and the addition of 600 ${\mu}M$ was less effective in improving TAG accumulation. The expression of acetyl-coenzyme A carboxylase alpha, fatty acid synthase and fatty acid-binding protein 3 was inhibited when palmitate or stearate were added in culture medium, whereas cluster of differentiation 36 and CSN1S1 mRNA abundance was increased in a concentration-dependent manner. The mRNA expressions of peroxisome proliferator-activated receptor gamma, mammalian target of rapamycin and signal transducer and activator of transcription 5 with palmitate or stearate had no significant differences relative to the control. These results implied that certain concentrations of saturated LCFA could stimulate cell proliferation and the accumulation of TAG, whereas a reduction may occur with the addition of an overdose of saturated LCFA. Saturated LCFA could up-regulate CSN1S1 mRNA abundance, but further studies are necessary to elucidate the mechanism for regulating milk fat and protein synthesis.