• Journal of Pharmaceutical Investigation
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• 제28권1호
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• pp.15-23
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• 1998

Extract of Centella asiatica(ECA), which is poorly water-soluble extract from the Centella asiatica is known to express excellent wound healing properties. $ECA-{\beta}-cyclodextrin$ $(asiaticoside-{\beta}-cyclodextrin\;and\;genin-{\beta}-cyc1odextrin)$ solid dispersion system, which was prepared by freezedrying method, was formulated as gels containing poloxamer 407 and propylene glycol, and evaluated with respect to their viscosity, stability, skin permeation and drug amount in the skin of hairless mouse. The average molar ratio $asiaticoside-{\beta}-CD$ and $genin-{\beta}-CD$ was 1:1.7 and 1:22, respectively. When the molar ratio of genin and ${\beta}-CD$ was 1:5, madecassic acid made 100% solid dispersion system and asiatic acid about 65%. In dissolution study, >99% of asiaticoside from $asiaticoside-{\beta}-CD$ was dissolved in 5 minutes, and >99% madecassic acid and >64% asiatic acid from $genin-{\beta}-CD$. The apparent viscosity of poloxamer 407 gels with $ECA-{\beta}-CD$ solid dispersion system increased in proportion to poloxamer 407 and propylene glycol concentration. In the accelerated stability test, all $ECA-{\beta}-CD$ poloxamer 407 gels showed that asiaticoside was most stable and madecassic acid stable and asiatic acid similar to stability of gel with free ECA. The permeation amount of asiaticoside in poloxamer gels through hairless mouse skin decreased as the concentration of poloxamer 407 increased. When propylene glycol was added at the level of 10%, the permeation amount of asiaticoside at poloxamer gels through hairless mouse skin increased but from 15% it decreased. The permeation of asiaticoside into the skin of hairless mouse was estimated to be about $0.10\;{\mu}g/cm^2$.

• Elastomers and Composites
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• 제48권3호
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• pp.190-194
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• 2013

본 연구에서는 피마자유 유래의 sebacic acid를 isophthalic acid 및 glycol과 병용하여 폴리에스터 폴리올을 중합하고 이어서 폴리우레탄 접착제를 제조하였다. 접착력을 측정한 결과에서 sebacic acid를 병용한 폴리올이 adipic acid를 사용한 폴리올 보다 응집에너지가 커서 접착력이 우수하게 나타났고, glycol은 선형구조 보다 메틸기를 포함하는 가지구조가 더 좋은 접착력을 보였다. 쇄연장제는 1,4-butane diol(BD)를 사용한 것이 가장 접착력이 좋게 나타났다. 또한 TGA 측정결과 내열성은 BD가 가장 높고, 1,2-propylene glycol(PG)가 다음, ethylene glycol(EG)가 가장 낮았다. DMA 측정에서 유리전이온도는 PG, EG, BD의 순서로 높게 나타났다.

• 한국산학기술학회논문지
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• 제4권1호
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• pp.47-49
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• 2003

태양전지에 소모되는 비용중의 30% 이상이 silicon 기판의 가공 및 silicon자체의 비용이다. 본 연구에서는 이러한 비운을 절감하기 위해 silicon기판대신 STS 304를 사용하고자 한다. STS 304를 태양전지용 기판으로 사용하기 위해서는 고도천 연마된 표면을 필수조건으로 하기 때문에 STS 304에 전해연마를 실시하여 AFM으로 표면의 거칠기를 살펴보았다 또 한, 표면 조도의 향상을 위해 최적의 연마조건에서 leveller를 첨가하였다. 인산($H_3PO_4$)을 기본으로 한 전해연마액에 2A의 전류와 극간거리 0.7cm의 조건하에서 STS 304의 최적 전해연마조건을 찾기 위해 전해액의 온도는 $80^{\circ}C{\sim}120^{\circ}C$, 연마시간은 3~2분간 전해연마를 실시하였다. 그 결과 2A/$cm^2$, $80^{\circ}C$, 10분에서 27.9nm의 표면조도를 보였으며, leveller로 사용된 glycerine, ethylene glycol, propylene glycol의 영향을 연구하였다. Leveller 중에서는 ethylene glycol을 0.4g/l 첨가하였을 때 표면조도가 약 15nm로서 그 효과가 가장 좋았다.

• 한국염색가공학회지
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• 제13권6호
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• pp.381-390
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• 2001

The optimum carrier concentrations were obtained by the maxmium exhaustion ratios of polyester fabrics at 8$0^{\circ}C$ . The optimum concentrations of methylsalicylate, acetophenone, anisole, propiophenone, 2-ethyl hexyl alcohol, ethylene glycol and propylene glycol were $3g/\ell,\;12g/\ell,\;7g/\ell,\;5g/\ell,\;3g/\ell,\;35g/\ell,\;and\;40g/\ell$, respectively Azo, anthraquinone, and quinoline disperse dyes were quite stable up to PH 10.3, but nitro disperse dye were severely hydrolyzed in alkaline dyeing. The tensile strength decreased with increasing dyebath pH because the polyester fabrics were easily decomposed by alkali. The reduction cleaning could be canceled in alkaline dyeing because the carriers were solved by alkali during dyeing.

• 한국염색가공학회지
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• 제13권6호
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• pp.23-23
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• 2001

The optimum carrier concentrations were obtained by the maxmium exhaustion ratios of polyester fabrics at 80℃. The optimum concentrations of methylsalicylate, acetophenone, anisole, propiophenone, 2-ethyl hexyl alcohol, ethylene glycol and propylene glycol were 3g/ℓ, 12g/ℓ, 7g/ℓ, 5g/ℓ, 3g/ℓ, 35g/ℓ, and 40g/ℓ, respectively. Azo, anthraquinone, and quinoline disperse dyes were quite stable up to pH 10.3, but nitro disperse dye were severely hydrolyzed in alkaline dyeing. The tensile strength decreased with increasing dyebath pH because the polyester fabrics were easily decomposed by alkali. The reduction cleaning could be canceled in alkaline dyeing because the carriers were solved by alkali during dyeing.

• Journal of Pharmaceutical Investigation
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• 제27권4호
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• pp.279-286
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• 1997

In order to formulate 2% ibuprofen solution, the effects of various solublizing agents, such as cosolvents (propylene glycol, polyethylene glycol, glycerin), a complexing agent $(CELDEX{\circledR}\;CH20)$, surfactants $(Poloxamers\;and\;Cremophor{\circledR}\;RH40)$ on the solubility of ibuprofen in aqueous solution were evaluated. Among them, Poloxamer 407 and $Cremophor{\circledR}$ RH40 showed the excellent capacity on the solubilization of ibuprofen. After 2% ibuprofen solution of choice were administered orally to rats, in reference to a 2% ibuprofen syrup in the market, the pharmacokinetic parameters were determined. The absorption rate of ibuprofen from the solution was higher than that from the suspension.

• Fisheries and Aquatic Sciences
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• 제15권1호
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• pp.77-81
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• 2012

We assessed the toxicity of cryoprotectant agents (CPAs) to gametophytic thalli of red alga Porphyra yezoensis at room temperature. The CPAs used were: dimethyl sulfoxide (DMSO), ethylene glycol (EG), glycerol (GC), 1,2-butanediol (1,2-BD), 1,3-butanediol (1,3-BD), 2,3-butanediol (2,3-BD), 1,3-propanediol (1,3-PD) and propylene glycol (PG). CPA concentrations of 10, 15, 20, 25, 30, 35, 40, 45, and 50% were employed with 30 or 60 s immersion. The toxicity of the eight CPAs to gametophytic thalli of P. yezoensis was in the order: 1,3-BD < DMSO ${\approx}$ 2,3-BD ${\approx}$ PG ${\approx}$ EG < GC < 1,3-PD ${\approx}$ 1,2-BD. All thalli were more sensitive to high CPA concentrations, and most (>75%) thalli survived exposure to 10-25% CPA for 60 s. These data will facilitate selection of the optimal cryoprotectant concentration for cryopreservation of P. yezoensis thalli.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1997년도 추계총회 및 학술발표회 논문집
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• pp.126-130
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• 1997

A series of Thermoplastic polyurethane elastomers was prepared via a two-step polymerization process. The NCO/OH feed ratio of polyurethane synthesized in this study was varied from 1 to 1.3. Studies have been made on the effects of chemical and physical cross-linkina, and the properties of thermoplastic polyurethane elastomers based on isophorone diisocyanate (IPDI)/1,4-butanediol (BD)/poly(propylene glycol) (PPG, MW:2000), isophorone diisocyanate (IPDI)/BD /poly(oxytetramethylene) glycol (PTMG, MW:2000) was compared. These materials were characterized using FTIR spectrometer, dynamic mechanical thermal analyzer, and tensile retraction tester. PTMG based polyurethane elastomers showed higher elasomeric behavior than PPG based polyurethane elastomers at the same NCO/OH ratio. This feature has been connected with the specific nature of the polyols. The permanent set(%) was decreased with increasing maximum elongation from 50% to 300%.

• 한국수산과학회지
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• 제20권3호
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• pp.202-207
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• 1987

알긴산에 propylene oxide를 가하여 PGA를 제조 할 때의 에스테르화 조건을 구하고 이때 제조한 제품의 이화학적인 특성을 조사하였다. 1. 알긴산에 대하여 propylene oxide을 4몰 가할때까지 에스테르화가 증가하였으나 그 후는 큰 변화가 없었다. 2. 에스테르화가 잘 일어나는 알긴산의 함수량은 $30\%$ 이상이었으며 수분함량이 $70\%$ 이상인 경우는 제품의 탈수가 제대로 되지 않았으므로 수분함량을 $30\~70\%$로 하는 것이 좋았다. 3. 수분함량이 $44.15\%$인 알긴산에 대하여 Propylene oxide를 4몰 가하고 1시간 동안 반응시켰을 때 반응이 최대로 일어나는 온도는 $70^{\circ}C$이었다. 4. 수분함량이 $50.05\%$인 알긴산에 propylene oxide를 4몰 가하고 $70^{\circ}C$에서 반응시킬 때 반응시간 1시간까지 에스테르화율이 급격히 증가하였으나 그 후는 큰 차이가 없었다. 5. $2\%$ 및 $3\%$ PGA 용액의 pH에 대한 안정성을 검토한 결과 pH 3.0까지 점도의 저하가 거의 없었고 그 이하에서는 감소하였으며, $1\%,\;2\%,\;3\%$ 및 $5\%$의 PGA 용액은 의가소성유체의 특성을 보였고 pH를 변화시킨 경우에도 의가소성유체의 특성은 유지 되었다.

• 한국식품조리과학회:학술대회논문집
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• 한국식품조리과학회 2003년도 추계학술대회 및 사단법인 창립총회
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• pp.84-84
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• 2003

생면제조시 각종 인산염의 효과를 구명하기 위하여 PG(propylene glycol), 폴리인산나트륨, 메타인산나트륨, 피로인산나트륨 등을 단독 또는 복합으로 첨가하여 제면특성 및 저장 중 생기는 이화학적 특성을 비교, 조사하였다. 인산염의 단독 또는 복합 처리에 의한 amylogram 특성은 최고점도의 경우 대조구, PG, polyphosphate, pyrophosphate, metaphosphate, PG+poly., PG+pyro. 및 PG+meta. 첨가구에서 273, 269, 274, 260, 272, 295, 269 RVU이었고 setback 값은 대조구, PG, polyphosphate, pyrophosphate, metaphosphate, PG+poly., PG+pyro. 및 PG+meta. 첨가구에서 104, 97, 92, 99, 99, 95, 102 RVU이었다. (중략)