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      • SCOPUSKCI등재

        과열증기처리 반탄화 추출물의 항산화 효과 검증에 관한 연구

        오근혜(Geun Hye Oh),남정빈(Jeong Bin Nam),양승민(Seung Min Yang),정원희(Won Hee Joung),정진산(Jin San Jeong),신종민(Jong Min Shin),강석구(Seog Goo Kang) 한국펄프·종이공학회 2018 펄프.종이기술 Vol.50 No.2

        The antioxidant properties of the extracts from torrefied wood subjected to superheated steam treatment were investigated. Total polyphenolics, total flavonoids, DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity, reducing power, and FRAP (Ferric reducing antioxidant power) were determined to evaluate antioxidant activity. The total polyphenol content was 879.67±40.41 ㎎/mL at a concentration of 25 g/mL when the extract was subjected to a temperature of 300℃ for 10 min, and 759.67±25.17 ㎎/mL at a concentration of 25 g/mL at 350℃ for 10 min. The value of at 300℃ was 15.79% higher than that obtained at 350℃. Total flavonoid content was 111.18±3.55 ㎎/mL at a concentration of 25 g/mL at 300℃ for 10 min, and 80.58±2.58 ㎎/mL at a concentration of 25 g/mL at 350℃ for 10 min. The value at 300℃ was 37.97% higher than that obtained at 350℃. For the DPPH free radical scavenging activity, the highest scavenging activity was observed at a concentration of 6 g/mL. DPPH free radical scavenging activity at a concentration of 6 g/mL at 300℃ for 10 min was 89.83±0.03%, whereas at 350℃ for 10 min at the same concentration, it was found to be 87.99±0.1%. The value at 300℃ was 2.09% higher than that obtained at 350℃. Reducing power was determined to be 3.59±0.04 at a concentration of 25 g/mL at 300℃ for 10 min, and 2.92±0.1 at a concentration of 25 g/mL at 350℃ for 10 min. The value at 300℃ was 22.94% higher than that obtained at 350℃. FRAP was 1742±37 μM at a concentration of 25 g/mL at 300℃ for 10 min, and 1106±8 μM at a at 350℃ for 10 min. At 300℃, the FRAP value was 57.50% higher than that obtained at 350℃. Based on these results, we suggest that torrefied wood treated with superheated steam can be used in various applications because of its effective antioxidant properties.

      • KCI등재

        Effects of Industrial By-products on Reducing Heavy Metal Leaching in Contaminated Paddy Soil

        Oh, Se Jin,Oh, Seung Min,Kim, Sung Chul,Ok, Yong Sik,Ko, Tae Yol,Ji, Won Hyun,Yang, Jae E. 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.1

        Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain ($H_2SO_4:HNO_3=6:4$, pH 5.5 fixed) was used for feeding solution with flow rate of $0.78{\sim}0.88mL\;min^{-1}$. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

      • Bending Performance of Flexible Organic Thin-Film Transistors With/Without Encapsulation Layer

        Oh, Jongsu,Kim, Jin-Ho,Lee, So Young,Kim, Min Su,Kim, Jae Moon,Park, Keechan,Kim, Yong-Sang IEEE 2018 IEEE transactions on device and materials reliabil Vol.18 No.1

        <P>Flexible pentacene-based organic thin-film transistors (TFTs) were fabricated and their performance was investigated as a function of the bending radius and the thickness of the polydimethylsiloxane (PDMS) encapsulation layer. The TFTs were fabricated on a flexible polyimide film (film thickness: 75 <TEX>$\mu \text{m}$</TEX>), and encapsulated by a PDMS layer. Degradation of the device performance during application of a tensile bending stress of 3 mm was minimized by utilizing an encapsulation layer thickness of 75 <TEX>$\mu \text{m}$</TEX>, because the mechanical strain on the pentacene layer was almost off-set (tensile strain was applied to the bottom layer of the pentacene, and compressive strain was applied to the top layer of pentacene). At the tensile bending stress of 3 mm, the performance of the non-encapsulated TFT was degraded, whereas the encapsulated device showed great stability. This flexibility and bending stability were enabled by the use of the 75- <TEX>$\mu \text{m}$</TEX> PDMS encapsulation layer, due to the location of the pentacene active layer in the neutral region position. A mechanical reliability test was performed for 120 min with a bending radius of 3 mm, demonstrating that only the device with the 75- <TEX>$\mu \text{m}$</TEX> thick encapsulation layer showed stable device performance over a stress time of 120 min.</P>

      • KCI등재

        정신분열병에 대한 리스페리돈의 효과 및 안정성

        이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

        연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

      • KCI등재

        Effects of Industrial By-products on Reducing Heavy Metal Leaching in Contaminated Paddy Soil

        Se Jin Oh,Seung Min Oh,Sung Chul Kim,Yong Sik Ok,Tae Yol Ko,Won Hyun Ji,Jae E. Yang 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.1

        Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain (H₂SO₄:HNO₃ = 6:4, pH 5.5 fixed) was used for feeding solution with flow rate of 0.78~0.88 mL min-1. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

      • Layer-controlled thinning of black phosphorus by an Ar ion beam

        Park, Jin Woo,Jang, Sung Kyu,Kang, Dong Ho,Kim, Doo San,Jeon, Min Hwan,Lee, Won Oh,Kim, Ki Seok,Lee, Sung Joo,Park, Jin-Hong,Kim, Kyong Nam,Yeom, Geun Young Royal Society of Chemistry 2017 Journal of Materials Chemistry C Vol.5 No.41

        <▼1><P>BP thinning was carried out using a monoenergetic Ar<SUP>+</SUP> ion beam and the BP could be thinned without damaging the surface.</P></▼1><▼2><P>Black phosphorus (BP) is one of the most interesting two-dimensional (2D) layered materials due to its unique properties, including a band gap energy change from 0.3 eV (bulk) to 2.0 eV (monolayer) depending on the number of BP layers, for application in nanoelectronic devices. In general, 2D layered materials including BP have limitations in terms of synthesis due to the process factors such as time, temperature, <I>etc.</I>, and thus, a thinning technique from the bulk material to a 2D material needs to be used while controlling the removed layer thickness. In this study, layer-controlled thinning of BP was performed by using a controlled Ar<SUP>+</SUP> ion beam method and the BP thinning characteristics were investigated. By using the near monoenergetic ion energy in the range of 45–48 eV, BP could be thinned with the thinning rate of ∼0.55 nm min<SUP>−1</SUP> down to bilayer BP without increasing the surface roughness and without changing the chemical binding states. The BP oxide on the pristine BP could also be successfully removed using the same Ar<SUP>+</SUP> ion beam. 2D BP field-effect transistors (FETs) fabricated with the thinned bilayer–10-layer BPs exhibited electrical characteristics similar to those of pristine BP FETs suggesting no electrical damage on the BP layers thinned by the controlled monoenergetic Ar<SUP>+</SUP> ion beam.</P></▼2>

      • KCI등재후보

        pH, 이온종류 및 농도, 퇴적물의 성분에 따른 하천 내 불소의 거동특성

        이동민(Dong Min LEE),주광진(Kwang Jin Joo),최이송(ISong Choi),장광현(Kwang Hyeon Chang),오종민(Jong Min Oh) 응용생태공학회 2018 Ecology and resilient infrastructure Vol.5 No.1

        하천에 유입된 오염물질은 다양한 환경 조건에 의하여 수체 및 퇴적물의 상호작용에 따라 수체의 수질에 영향을 미친다. 특히 최근 수체의 수리학적 체류시간이 상대적으로 긴 정체수역 내에서는 퇴적물의 축적량이 증가하고 있어 퇴적물과 수체 내에서의 물질적 거동특성 파악은 중요한 수질적 관점 요소이다. 본 연구에서는 하천 내 pH, 이온종류 및 농도, 퇴적물의 점토함량에 따라 불소의 거동이 어떻게 변화하는지 검토하기 위하여 경기도에 위치한 중소하천을 대상으로 조건별 실험을 실시하였다. pH에 따른 흡착 및 용출특성 실험결과, pH가 높을수록 불소의 흡착량이 감소하였고, 용출되는 불소량은 증가하는 경향을 나타냈다. 이온농도 및 종류에 따른 흡착 및 용출특성 실험결과, Cl<SUP>-</SUP>, SO₄<SUP>2-</SUP> 이온은 불소의 흡착능에 큰 영향을 주지 않는 것으로 나타났으나, 불소와의 활발한 이온경쟁효과를 지닌 OH<SUP>-</SUP>와의 반응에서는 흡착량이 줄고, 용출량이 늘었음을 알 수 있었다. 퇴적물의 성분에 따른 흡착 및 용출특성 실험 결과 상대적으로 입경이 작은 Silt와 Clay 성분이 많이 포함된 시료에서 불소의 흡착량이 많고 용출되는 불소량이 줄어드는 것을 알 수 있었다. 이는 수체의 환경조건이 퇴적물 내 불소의 흡착 및 용출에 크게 영향을 미치기 때문에, 퇴적물 내 불소를 적절하게 관리하기 위해서는 수체의 환경조건에 대한 이해가 선행되어야 한다는 것을 의미한다. Water quality is affected by the pollutants flowing into rivers since the interaction between water bodies and sediments in various environmental conditions. Especially, accumulation of sediments increases in the stagnant water areas due to a relative long hydrological retention time in the water bodies. Therefore, it is an important factor of water quality to understand characterization of the material behavior in water bodies and sediments. In this study, the objective of the conditional experiments was small and medium sized streams located in Gyeonggi-do. To estimate how the changes of fluoride behavior, depending on the pH, ion type, concentration, and clay contents. The pH results showed a trend that adsorption amount of fluorine decreased and the dissolution of fluorine increased following by pH increasing. The concentration and type of ions results showed that Cl<SUP>-</SUP> and SO₄<SUP>2-</SUP> ions had no significant effect on the adsorption ability of fluorine, the amount of dissolution was increased because OH<SUP>-</SUP> ion had active competition with fluorine in the reaction. The ingredient of sediment results showed that the amounts of fluoride adsorption and dissolution were reduced in samples, which contain relatively large amounts of Silt and Clay components. This means that the environmental conditions of water bodies greatly affect the adsorption and dissolution of fluoride in the sediments, so that proper management of fluoride in the sediments must precede an understanding of the environmental conditions of the water bodies.

      • KCI등재후보

        간헐식 흐름방식을 활용한 수직 · 수평 습지의 정화효율 평가

        주광진(Kwang Jin Joo),이동민(Dong Min Lee),김기중(Ki Jung Kim),조용철(Yong Chul Cho),장광현(Gwang Hyeon Jang),최이송(I Song Choi),오종민(Jong Min Oh) 응용생태공학회 2017 Ecology and resilient infrastructure Vol.4 No.3

        본 연구에서는 부영양화의 원인이 되는 질소와 인의 제거 효율을 향상시킬 목적으로 광물질을 활용한 여재를 이용하여 호기, 혐기의 흐름조건을 만들어주기 위한 수직·수평 흐름 인공습지를 고안하여 아크릴 반응조로 제작한 후 성능평가를 진행하였다. 수직·수평 흐름형 인공습지의 경우 호기 및 혐기조건을 평가하기 위해서 반응조 내 용존산소(DO) 농도를 측정해본 결과 호기상태에서는 2.7 ㎎/L, 혐기상태에서는 N.D로 확인되어 목적에 부합된 결과가 확인되었다. 실험결과에서는 SS 저감효과가 140 min, 80 min, 60 min의 운전시간에서 각각 94%, 91%, 61%의 효율을 보였고, T-P의 경우 각각의 운전시간에 따라 84%, 71%, 63%의 저감효율을 보였다. 또한 T-N의 경우 각각의 운전시간에 따라 63%, 49%, 42%의 저감효율을 보여 기존의 습지가 12~24 hr 체류시간을 가지는 것에 비하여 짧은 운전시간에도 높은 처리효율을 보이는 것으로 확인되었다. 본 연구에서는 수직·수평 흐름 방식을 복합 적용하여 기존 인공습지의 단점을 보완하기 위해 기술개발을 진행한 것으로 어떠한 기능적 효과를 갖는지 확인하였고, 향후 이에 대한 현장적용을 위한 운영 및 관리적 차원의 메커니즘 연구가 추가로 진행 될 필요가 있다. Nitrogen and phosphorus are key factors in causing eutrophication of water body. In this study, ceramics media was selected to increase the removal efficiency of nitrogen and phosphorus. We designed vertical, horizontal flow constructed wetlands to create aerobic and anaerobic flow conditions by using the media, then proceeded to performance evaluations after acrylic reactors were produced. In the case of vertical and horizontal flow constructed wetlands, we measured oxygen concentrations to evaluate aerobic and anaerobic conditions. we got the result of 2.7 ㎎/L in the aerobic condition, N.D in the anaerobic condition respectively, which suited our purpose. The result of the combined vertical and horizontal flow condition showed that the removal efficiency of SS was 94%, 91%, 61% at 140 min, 80 min, 60 min of running times, respectively, and the removal efficiency of T-P was 84%, 71%, 63% during each running time. In case of T-N, the removal efficiency was 63%, 49%, 42% during each running time. We found that the reactor exerted better removal efficiency when in the short time compared to 12 - 24 hr residence time of existing wetlands. In this study, we conducted experiments to explore functional effects after applying combined vertical and horizontal flow methods in the field. Further study will be carried out to identify its mechanism and administrative perspective.

      • SCOPUSKCI등재

        개의 췌도분리에서 췌장의 팽창과 콜라겐 분해요소

        이상훈,김성주,박정환,김종성,오승훈,한진수,정인경,양태영,김동준,김광원,이문규,민용기,이명식,정재훈,함종렬 대한당뇨병학회 2000 Diabetes and Metabolism Journal Vol.24 No.2

        Backgrounds: One of the main problems conditioning the outcome of islet transplantation is the ability to separate a sufficient number of viable islets with preserved function. Islet purification is critically affected by all of the isolation stages. Thus, it is necessary to set up the standard isolation method that islets are separate well from acinar without compromising islet yield and viability. Methods: Twenty three adult mongrel dogs were used for the experiment of total pancreatectomy with islet isolation. The islets were properly isolated by a modified Recordi method. The obtained islets were further purified by centrifugation on discontinuous gradients using cell separation system (Model 2991, Cobe, Lakewood Colo). We evaluated islet number (islet equivalent number, 150 um equivalents/kg of recipient body weight, IEq/kg), purity, cell volume, viabilty, recovery rate, and comparison of outcome according to the isolation conditions. Results: 1) The mean of islet numbers before purification were 13543±9431Eq/kg, digestion times were 13.8±2.6 min., digestion temperature was 37.4±0.2℃, purity was 59.7?.0%, viability was 90.0±2.1%, cell volume was 4.7±1.1 mL, islet number after purification were 4064±361 IEq/kg, and recovery rate was 29±2.9%. 2) Isolated islet numbers were different according to the degree of pancreas distension with collagenase, digestion temperature, and digestion time. 3) The best conditions for islet isolation were above 37.5℃ in temperature at recirculation of collagenase, within 12 min in digestion time and well distended pancreas with collagenase. 4) According to multiple regression adjusted by variable factors, the degree of pancreas distension with collagenase and digestion time were independently associated factors for successful islet isolation. Conclusions: In this study, we concluded that the degree of pancreas distension with collagenase and digestion time were independent factors for successful islet isolation and the best conditions for islet isolation were above 37.5℃ in temperature at recirculation of collagenase, within 12 min in digestion time and well distended pancreas with collagenase.

      • KCI등재

        재사용이 가능한 나노복합재료 Fe<sub>3</sub>O<sub>4</sub>-ACCS-Ag의 제조 및 항균 특성 평가

        심재홍,김해원,김진원,서영석,오세강,조민,박정희,오병택,Shim, Jaehong,Kim, Hea-Won,Kim, Jin-Won,Seo, Young-Seok,Oh, Sae-Gang,Cho, Min,Park, Junghee,Oh, Byung-Taek 한국지하수토양환경학회 2015 지하수토양환경 Vol.20 No.3

        In this study, Fe<sub>3</sub>O<sub>4</sub>-ACCS-Ag nanoparticles (NPs) were successfully synthesized using silica extracted from corn cob ash. The synthesized Fe<sub>3</sub>O<sub>4</sub>-ACCS-Ag NPs were characterized using X-ray diffraction (XRD), scanning electron microscopyenergy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM) and fourier transform infrared spectroscopy (FTIR). In addition, the potential application of Fe<sub>3</sub>O<sub>4</sub>-ACCS-Ag NPs as an antibacterial material in water disinfection was investigated using Escherichia coli ATCC 8739 as model bacteria. The antibacterial activity of synthesized composite material showed 99.9% antibacterial effect within 20 min for the tested bacteria. From this experiment, the synthesized Fe<sub>3</sub>O<sub>4</sub>-ACCS-Ag nanocomposites also hold magnetic properties and could be easily recovered from the water solution for its reuse. The reused nanocomposites presented the decreasing antibacterial efficiencies with the reuse cycle but the composite used three times still killed 90% of bacteria in 20 min.

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