Development of a Polyaniline-coated Monolith Reactor for the Synthesis of Cephalexin Using Penicillin G Acylase Aggregates

안영덕,이중헌 한국생물공학회 2018 Biotechnology and Bioprocess Engineering Vol.23 No.3

A monolith reactor for the synthesis of cephalexin was developed using capillary columns. The micro channel in the monolith reactor was coated with polyaniline (PANI), and penicillin G acylase was aggregated with PANI using 0.5% of glutaraldehyde as a cross-linker. The developed monolith reactor exhibited many advantages over other enzyme reactors such as batch and continuous reactors. It showed fast enzyme reaction rates owing to the decrease in external mass transfer and internal diffusion limitations. The reactor can easily be scaled up by bundling together multiple monolith reactors, enabling a corresponding increase in feed rate. Furthermore, the monolith reactor showed good operational stability, with 95% of its original activity maintained after 48 h of continuous operation. The PANI coating on the surface of the capillary column increased the enzyme immobilization capacity and conversion was increased from 15.4% to 70.6% after PANI coating. The conversion ratio increased to approximately 70.6% with an increase in residence time and reactor length.

감마선 조사에 의한 Acetylsalicylic Acid의 분해

안영덕,이경훤,이오미,김태훈,정인하,유승호,이면주 한국방사선산업학회 2011 방사선산업학회지 Vol.5 No.3

Acetylsalicylic acid (ASA) has been issued recently in contaminated water environmentsbecause of potential impacts on ecosystem and public health. This study was aimed at investigatingthe possibility of ASA degradation using gamma ray irradiation. In addition, the use ofsodium persulfate, hydrogen peroxide, ferrous sulfate were tested in order to examine a synergisticeffect with gamma ray. The absorbed dose was ranged from 0.2 to 10 kGy and the concentrationof oxidants were from 0.1 to 10 mM in this study. The concentration of ASA was graduallydecreased corresponding to the increase of the absorbed dose. When soudium persulfate wassimultaneously applied, most of the parent compound was completely degraded even at a low doseof 0.8 kGy. The removal efficiency of total organic carbon was 90% even at the highest dose of 10kGy without sodium persulfate. However, the efficiency was dramatically enhanced up to 98% atthe same dose by adding 10 mM of oxidants. It was suggested that hydroxyl radical (OH∙) andsulfate radical (SO4-∙) were formed in the system and made roles in degrading ASA at the sametime.

LOTOS에서의 모듈 구조 설계에 관한 연구

안영덕(Young-Duck Ahn),서동수(Soo-Dong So),송주석(Joo-Seok Song) 한국정보과학회 1991 한국정보과학회 학술발표논문집 Vol.18 No.2

LOTOS는 분산시스템이나 OSI의 서비스 및 프로토콜을 명세하기 위해서 ISO에서 IS 8807로 1989년에 표준화된 명세 언어이다. 표준 LOTOS에서 제공하는 계층 구조 개념은 능동적 개체인 프로세스와 수동적 개체인 데이타 타입 사이에 복잡하고 부자연스러운 인터페이스를 제공하고 있다. 특히 모든 명세 문서는 단 하나만 존재하여, 시스템이나 프로토콜이 큰 경우 효율적인 명세를 하기가 어렵다. 본 연구에서는 모듈 개념을 LOTOS에 도입하여 효율적인 시스템 명세를 할 수 있도록 하며, 더불어 프로세스와 데이타 결합으로 두 개체 사이에 유연한 인터페이스를 제공한다.

부동산투자의 위험관리 방안에 관한 연구

안영덕(Young-Duk AHN) 조선대학교 지식경영연구원 2009 기업과 혁신연구 Vol.2 No.1

부동산투자 위험과 수익률의 상관관계는 높은 기대수익(expected return)을 위해서 높은 위험을 부담하여야 하며 낮은 기대수익에 만족하는 경우에는 높은 위험을 택하지 않아도 된다. 또한 부동산투자는 현재의 소비를 희생한 대가(economic rewards)로서 시간에 대한 비용이며 또한 불확실성의 대가에 위한 위험의 비용이다. 자산관리 중에서 가장 핵심이 되는 부문은 위험관리라 할 수 있다. 규제완화와 세계화가 심화되면서 투자환경의 불확실성이 증가함에 따라, 부동산 투자와 관리에 있어서 고려해야 될 위험요소가 많아지게 되었으며, 그 결가가 위험관리 역시 그 중요성이 커가고 있다. 이러한 관점에서 본 연구는 부동산 투자에 관하여 이론적으로 고찰하고, 부동산수익률 동향과 주요 위험요인 즉, 경기수준, 인플레이션 등 거시경제 변수가 부동산 수익률과의 관계를 고찰하여, 이를 바탕으로 효과적인 위험관리 방안을 제시하는 데 그 목적이 있다. Real estate has been recognized as the safest asset, but as shown in plummeting prices of land during the economic crisis, the days have gone when the real estate was cited as safe investment. Once economy goes beyond high growth stage, investment in real estate has to be made in consideration of profitability like any other investment. With regard to investment in real estate expected to emerge as important social issue according to changes in economic situation, the study aims to create environment that can induce investment in real estate by systematically analyzing all theories related to real estate investment and analyze profit and risk of the real estate investment by examining decision-making process related to investment in stage so that it can figure out correlation between real estate systemic risk factors and risk through recognition of risk pooling, composition of real estate portfolio and importance of analysis of environment of investment, This study presents the major risk factors in the real estate investment and management. We analyze the effect of the systemic risk factors, in particular major macroeconomic variables, on the return on the real estate investment.

DTSPN을 이용한 프로토콜 분석과 성능평가용 툴 개반

안영덕(Young-Duck Ahn),이종현(Jong-Hyun Lee),송주석(Joo-Seok Song) 한국정보과학회 1992 한국정보과학회 학술발표논문집 Vol.19 No.2

컴퓨터망이 발달함에 따라 복잡한 프로토콜이 필요하게 되어서 프로토콜을 형식적으로 검증하고 분석할 수 있는 툴의 필요성이 증가하고 있다. 본 연구에서는 페트리 네트로 모델링된 프로토콜을 검증(validate)하고 그 성능을 평가할 수 있는 툴의 개발을 목적으로 한다. 툴은 Molloy가 제안한 DTSPN(Discrete Time Stochatistic Petri Nets)를 이용하며, 상태천이 그래프를 생성하여 프로토콜을 검증하고 이이서 생성된 상태천이 그래프가 마르코프 체인과 동일한 성질을 가짐을 이용하여 모델링된 프로토콜의 성능을 평가한다.

벼물바구미의 생식과 발육에 미치는 온도의 영향

이기열,장영덕,안기수,강호중,박성규 한국응용곤충학회 2002 한국응용곤충학회지 Vol.41 No.2

벼물바구미의 생식과 발육에 미치는 온도의 영향을 2$0^{\circ}C$에서 3$0^{\circ}C$사이의 온도에서 수행하였다. 20, 25, 3$0^{\circ}C$에서 산란전기간은 5월에 채집한 월동성충보다 3월에 채집한 충에서 길었다. 그러나 같은 온도조건에서 산란기간은 3월에 채집한 월동성충보다 5월에 채집된 충이 길었다. (16.9일, 22.0일).산란기간이 긴 5월 채집충이 산란수도 많은 결과를 가져왔다. 난기간은 15.1일(2$0^{\circ}C$)에서 4.5일(3$0^{\circ}C$)로 온도가 높을수록 짧았고, 그리고 부화율은 27$^{\circ}C$에서(100%) 가장 높았다. 난부터 성충까지의 발육기간은 온도가 높아질수록 짧았다; 2$0^{\circ}C$에서 77.9일, 3$0^{\circ}C$에서 38.3일이었다. 난 발육영점온도(T)와 유효적산온도(K)는 각각 16.3$^{\circ}C$와 62.1일도이었다. 난에서 성충우화까지는 각각 13.9$^{\circ}C$와 577.6일도이었다. 제1세대 성충은 2$0^{\circ}C$에서 산란하지 못하였고, $25^{\circ}C$와 3$0^{\circ}C$에서는 산란하였다. 내적자연증가율(r$_{m}$ )은 온도가 높을수록 증가되었다. 1세대당 순증식율(Ro)은 $25^{\circ}C$에서 가장 높았다(75.3). This study was carried out to test the effects of temperatures between 2$0^{\circ}C$ and 3$0^{\circ}C$ on the reproduction and development of the rice water weevil, Lissorhoptrus oryzophilus. Preoviposition periods were much longer (17.2 to 51.0 days) in the overwintering adult females collected in March than those collected in May, regardless of temperature. Oviposition periods, however, were longer (16.9 to 22.0 days) in the adult females collected in May than those collected in March at the same temperatures. The longer oviposition period observed in the females collected in May were directly associated with higher fecundity. Egg periods were shortened from as temperature increased, but the hatching rate was highest (100%) at 27$^{\circ}C$. The developmental periods from egg to adult were shortened as temperature increased : from 77.9 days at 2$0^{\circ}C$ to 38.3 days at 3$0^{\circ}C$. The developmental zero point temperature (T) and the total effect temperature (K) for egg were 16.3$^{\circ}C$ and 62.1 dgree days, respectively. The T and K from egg to adult emergence were 13.9$^{\circ}C$ and 577.6 dgree days, respectively. The adult females of the first generation did not oviposit at 2$0^{\circ}C$, but did at $25^{\circ}C$ and 3$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) increased as temperature augmented. Net reproductive rate (Ro) per generation was highest (75.3) at $25^{\circ}C$.>.

Acetaminophen의 감마선 분해에 대한 산화제 영향

이면주,안영덕,이경훤,이오미,김태훈,정인하,유승호 한국방사선산업학회 2011 방사선산업학회지 Vol.5 No.4

This study was aimed to investigate the effect of oxidants on biodegradability anddecomposition of acetaminophen (ACT) by gamma ray. Three kinds of chemical, potassiumpersulfate, hydrogen peroxide and ferrous sulfate were selected as an oxidant. The absorbed dosewas ranged from 0.2 to 10 kGy and the concentration of oxidants was from 0.1 to 10 mM and theinitial concentration of acetaminophen was 30 mg l-1 in this study. The concentration of ACT wasgradually decreased corresponding to the increase of the absorbed dose. However, mineralizationof ACT was not occurred by the increased of the absorbed dose. When the 10 mM of oxidantsapplied to the ACT aqueous solution, the concentration of ACT was rapidly decreased accordingto absorbed dose and the mineralization was observed in potassium persulfate. Biodegradabilityof ACT with potassium persulfate was higher than that of ACT without potassium persulfate inlower absorbed dose and decreased according to higher absorbed dose.

Laser-assisted Machining 을 이용한 WC 가공과 절삭온도에 관한 연구

맹환호(H. H. Maeng),박영덕(Y. D. Park),김승현(S. H. Kim),김동환(D. H. Kim),장형욱(H. U. Jang),정진성(J. S. Jeong),명태식(T. S. Myung) Korean Society for Precision Engineering 2020 한국정밀공학회 학술발표대회 논문집 Vol.2020 No.9월

시설복숭아에서 호박벌(Bombus ignitus) 화분매개 활동 및 상품성

이기열,안기수,박성규,이상범,김삼은,장영덕 한국응용곤충학회 2002 한국응용곤충학회 학술대회논문집 Vol.2002 No.1

Solid-phase Synthesis of Folate–Chlorin Conjugates for Selective Photodynamic Therapy and the Effect of Linker Variation

이선민,안영덕,문효영,고병숙,김태영,서지원,김민곤 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.12

Here, we evaluated the effect of linkers conjugating a chlorin-based photosensitizer, 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), and folic acid to target cancer cells. Folate–HPPH conjugates with peptide, polyethylene glycol (PEG), peptoid, or 7-aminoheptanoic acid (AHA) linkers were synthesized on a solid-phase and evaluated for photodynamic therapy (PDT) efficacy. Compared to free HPPH, the folate-linker-HPPHs were effectively internalized into tumor cells and exhibited superior PDT effect upon irradiation. Tumor-targeting PDT efficacy was influenced by linker variation, with in vitro photocytotoxicities of peptide > PEG > AHA > peptoid, paralleling water solubility of the linkers. Thus, linker choice significantly affects targeted PDT efficacy providing useful information for linker design.