• Korean Chemical Engineering Research
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• 제48권5호
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• pp.598-602
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• 2010

본 논문에서는 다량의 수소를 포함한 다성분계 원료가스로부터 수소를 분리해 내는 분리막 시스템에 대하여 CFD 모델링과 모사를 수행하였다. 분리막 시스템은 환형 실린더 타입으로 원료가스의 유입을 위한 외부 lumen side와 sweeping gas가 유입되는 내부 permeation side로 구성된다. Lumen side의 운전온도와 압력은 $374^{\circ}C$, 7 기압 permeation side의 sweeping gas의 도입 온도와 압력은 $374^{\circ}C$, 3기압이며, 이러한 조건에서 운전이 가능한 Pd 분리막을 사용하였다. Sweeping gas의 흐름 방향에 따른 향류 및 병류 흐름에 대하여 각각 CFD 모사를 수행하였으며 수소 몰분율, 수소분압, 수소 플럭스 등에 대하여 결과를 비교하였다. 또한 lumen side의 원료가스 도입유속을 변화시켜 모사를 수행하고, 이에 따른 막분리 시스템의 효율을 비교하고 이에 대하여 고찰하였다.

• Journal of Pharmaceutical Investigation
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• 제40권1호
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• pp.23-31
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• 2010

In our previous work on levodopa delivery at pH 2.5 using iontophoresis, we found that cathodal delivery showed higher permeation than anodal delivery and electroosmosis plays more dominant role than electrorepulsion. In this work, we studied the transdermal transport of levodopa at very low pH (pH=1.0) where all levodopa molecules are cations, and evaluated some factors which affect the transdermal transport. The transport study at pH 2.5 was also conducted for comparison. The contribution of electrorepulsion and electroosmosis on flux was also evaluated. Using stable aqueous solution, the effect of electrode polarity, current density, current type and drug concentration on transport through skin were studied and the results were compared. We also investigated the iontophoretic flux from hydroxypropyl cellulose (HPC) hydrogel containing levodopa. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell. Full thickness hairless mouse skin were used. Current densities applied were 0.2, 0.4 or $0.6\;mA/cm^2$. Contrary to the pH 2.5 result, anodal delivery showed higher flux, indicating that electrorepulsion is the dominant force for the transport, overcoming the electroosmotic flow which is acting against the direction of electrorepulsion. Cumulative amount of levodopa transported was increased as the current density or drug concentration was increased. When amount of current dose was constant, continuous current was more beneficial than pulsed current in promoting levodopa permeation. Similar transport results were obtained when hydrogel was used as the donor phase. These results indicate that iontophoretic delivery of zwitterion such as levodopa is much complicated than that can be expected from small ionic molecules. The results also indicate that, only at very low pH like pH 1.0, electrorepulsion can be the dominant force over the electroosmosis in the levodopa transport.

• 멤브레인
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• 제19권2호
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• pp.157-164
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• 2009

소수성, 고무상 고분자인 polydimethylsiloxane (PDMS) 소재를 대상으로 치밀한 단일막과 복합막을 제조하였으며 이들을 이용한 투과증발법을 통해 바이오부탄올을 농축하는 실험을 수행하였다. 바이오부탄올 회수를 위해 $1{\sim}5wt%$의 부탄올이 함유된 모델 수용액을 대상으로 조업온도$(20{\sim}40^{\circ}C)$와 막두께$(1{\sim}100{\mu}m)$를 변화시키면서 PDMS막의 투과증발 특성을 조사하였다. $100{\mu}m$ 두께 PDMS 단일막의 경우 공급부탄올의 농도가 증가할수록 포집된 부탄올의 농도, 선택도, 투과도가 증가하였다. 이러한 결과는 물보다 부탄올에 대한 PDMS 소재의 친화성과 막 사슬 내의 큰 자유부피(free volume)로 부탄올에 대한 확산저항이 적기 때문에 부탄올에 대한 선택도와 투과도가 높은 것으로 파악되었다. 조업온도를 $20{\sim}40^{\circ}C$로 증가시키며 투과증발특성을 조사한 결과, 온도의 상승에 따라 포집된 부탄올의 농도, 선택도, 투과도 모두 증가하였다. PDMS막의 두께가 $100{\mu}m$에서 $1{\mu}m$로 얇아질수록 포집된 부탄올의 농도와 선택도는 감소하였으며 투과도는 증가하는 경향을 보였다.

• 멤브레인
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• 제22권6호
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• pp.424-434
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• 2012

본 연구에서는 CVD법으로 세라믹 막을 제조하였다. 튜브의 ${\alpha}-Al_2O_3$ 지지체 위에 Ga 염이 첨가된 ${\gamma}-Al_2O_3$를 코팅하였고, 실란화합물인 tetramethylorthosilane (TMOS) 를 $650^{\circ}C$에서 화학적 기상 증착법으로 막에 증착하였다. 제조된 세라믹 막을 사용하여 수소, 질소, 이산화탄소, 메탄의 단일조성 기체투과 실험을 $600^{\circ}C$에서 시행하였다. Ga 염 비첨가 시, $600^{\circ}C$ 수분 처리 실험의 $H_2/N_2$ 선택도가 926에서 829로 감소한 반면, Ga 염 첨가 시에는 910에서 904로 안정하였다. 이 결과를 통해, 막에 금속염을 첨가하여 제조한 막이 수분 안정성을 향상시킴을 확인하였다.

• Journal of Pharmaceutical Investigation
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• 제36권4호
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• pp.253-262
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• 2006

This study was performed to investigate the effects of treatment for dermatitis using the herbal gel preparations. Scutellariae Radix(SR) and Zingiberis Rhizoma(ZR) were used for the purpose of herbal preparations. Baicalin, baicalein are the ingredients of SR, having biological effects like anti-inflammatory, anti-oxidative, anti-bacterial and antiallergic action. 6-Gingerol is one of the ingredients of ZR having biologicai effects like anti-inflammatory and analgesic action. The three types of hydrogels(SRE, SRH, SZH) were formulated with Carbopol 940, Labrasol, Triethanolamine etc. Baicalin was hydrolysed to baicalein by $\beta$-glucuronidase for the purpose to increase rate of skin permeation. Content of ingredients by HPLC determination, rate of skin permeation using Franz type diffusion cell, anti-oxidative activity for the free radical, hydroxyl radical, superoxide, anti-inflammatory by using carrageenan injection, efficacy on the dermatitis induced by 2,4-dinitro-chlorobenzene(DNCB) were experimented. Baicalein showed higher permeability than baicalin, so it is considered that baicalein was more suitable form than baicalin for transdermal absorption by its lipophilic property. In the anti-oxidative experiments, SZH gel was the most effective scavenging activity than the other gels in all experiments. In anti-inflammatory test, SRM and SZH gel more decreased edma rapidly than SRE gel. In case of using SZH gel, treatment period for the dermatitis was more declined than that of other gel groups. These results suggests that the SZH hydrogel could be suitable preparations for the treatment of dermatitis.

• Journal of Pharmaceutical Investigation
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• 제34권2호
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• pp.115-123
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• 2004

Geniposide and its related iridoid compounds have been used in traditional herbal medicine for thε treatment of Jaundice hepatic diseases and various inflammatorys. For the purpose to increase trandsdermal absorption, the hydrolyzed products of Gardeniae Furctus were identified and assayed of active ingredients and investigated trandsdermal absorption and anti-inflammatory effects. Geniposide was hydrolyzed to genipin by ${\beta}-glucosidase$ and it was suggested that genipin was more suitable form than geniposide for transdermal absorption by its lipophilic property. Using Franz type diffusion cell and the skin of hairless mouse, the permeation rate of hydrolyzed products and their emulsion preparation were determined. Genipin have more increased absorption ratio through the skin of hairless mouse than geniposide. Also, the emulsion of hydrolyzed products of extracts showed higher permeability than that of nonhydrolyzed preparations. After 9 hours $280.85\;{\mu}g/cm^2$ of genipin was absorbed and $193.52\;{\mu}g/cm^2$ in case of geniposide. The Js of geniposide and genipin were $26.27{\pm}4.11\;{\mu}g/cm^2/hr$ and $40.35{\pm}5.04\;{\mu}g/cm^2/hr$ respectively. After carrageenan injection, the swelling was increased repidly to 24 hr and maintained as plateau. but emulsion group weer reached about 2.5 mL and the swelling decreased successively form 24 hr to 72 hr. The anti-inflammation effects of extracts and hydrolyzed products emulsion were increased with significant difference with control group after 24 hr, 48 hr and 72 hr. In carrageenan induced edema, inhibition of swelling was increased in case of hydrolyzed product emulsion compare with nonhydrolyzed group at 24 hr, 48 hr and 72 hr after swelling. In histological study, the anti-inflammatory effects of hydrolyzed products were remarkable at 48 hr and 72 hr compare with nonhydrolyzed. Hydrolyzed products of Gardeniae Fructus extracts containing genipin would be a suitable preparation to increase the transdermal absorption and anti-inflammatory effects.

• 동력기계공학회지
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• 제19권4호
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• pp.5-10
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• 2015

Dust collector is one of the most widely used equipment among the method of separating particles, it filters exhaust gas having various kinds of dusts through several filters installed on parallel. This research investigated the moving characteristic of Honeycomb-type carbon filter in pressure drop of smoking collector's ventilation system. It also compared pressure transmission coefficient through pressure drop according to flow velocity change.

• Fisheries and Aquatic Sciences
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• 제13권1호
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• pp.84-87
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• 2010

A peptide that inhibits HIV-1 protease was isolated from a hydrolysate of oyster (Crassostrea gigas) proteins digested with thermolysin. The peptide was using membrane filtration, gel permeation chromatography, ion exchange chromatography, and reverse-phase high performance liquid chromatography. Amino acid sequence of the peptide was determined to be Val-Phe-Glu-Leu. Chemically synthesized Val-Phe-Glu-Leu showed an $IC_{50}$ value of 106 ${\mu}M$.

• 대한화학회지
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• 제28권6호
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• pp.393-398
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• 1984

겔투과 크로마토그래피와 실리카겔크로마토그래피등을 이용하여 여러가지 천연아스팔트에서 금속포르핀을 얻었으며 크로마토그래피 용액을 알루미나로 처리한 후 피리딘으로 추출하여 보다 농축된 금속 포르피린을 얻을 수 있었다. 금속 포르피린에서 포르피린 고리를 파괴하지 않고 금속을 제거하여 여러가지 형태의 프르피린을 얻었다.

• 한국세라믹학회지
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• 제51권5호
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• pp.477-480
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• 2014

An $Al_2O_3$-CuO-ZnO (ACZ) precursor powder was synthesized by a facial sol-gel process using a nonionic surfactant span 80 as the chelating agent to improve the surface area and morphology. When creating a hydrogen membrane, several kinds of properties are required, such as easy dissociation of hydrogen molecules, fast hydrogen diffusion, high hydrogen solubility, and resistance to hydrogen embrittlement. ACZ-Ni composite membranes (cermet) were prepared with this precursor and pure Ni powder via the hot press sintering (HPS) method. The ACZ powder was characterized by XRD, BET, and FE-SEM. Hydrogen permeation experiments were performed by Sievert's type of hydrogen permeation membrane equipment. The hydrogen permeability of ACZ/Ni 10 wt% and ACZ/Ni 20 wt% was obtained as 7.2 and $10molm^{-2}s^{-1}$ at RT, respectively. These values of the corresponding membranes were slightly increased with increasing pressures.