농업 부산물 바이오매스 특성에 따른 반탄화 공정 최적화: 1. 질량감소 예측 모델 개발

김석준 ( Seok Jun Kim ),오광철 ( Kwang Cheol Oh ),박선용 ( Sun Young Park ),조라훈 ( La Hoon Cho ),김민준 ( Min Jun Kim ),이충건 ( Chung Geon Lee ),정인선 ( In Seon Jeong ),전영광 ( Yeong Kwang Jeon ),김대현 ( Dae Hyun Kim ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.2

본 연구에서는 국내에서 버려지고 있는 농업부산물의 에너지로서 이용 가능성이 분석되었다. 농업부산물 바이오매스는 화석연료와 동일하게 활용가능하며 지속적으로 생산되는 에너지원이다. 하지만 높은 수분 함량에 따른 보관문제, 화석연료와 비교하여 낮은 발열량등의 단점을 지니고 있어 전처리공정이 요구된다. 따라서 효율적인 활용을 위한 전처리 공정으로 반탄화가 선정되었다. 반탄화공정은 수분제거를 통해 에너지가 증가되어 저장·운송에 이점으로 인하여 최종적인 에너지 가치가 증대된다. 실험은 문헌탐색을 통한 반탄화공정 적용 가능 농업부산물(고추대)과 실험조건(200, 230, 270C, 10, 20, 30, 40 min)이 선정되었으며, 1차원 시뮬레이션을 통한 분석이 이루어졌다. 이때 반탄화 실험을 통하여 발생되는 질량감소량과 발열량 변화량은 높은 상관관계(r²=0.9528)를 가지고 있으며 본 연구에서는 반탄화공정의 질량감소량 예측 모델개발이 수행되었다. 질량감소량 분석을 위하여 열 중량 분석(Thermo Gravimetric Analyzer, TGA)이 수행되었으며 승온속도(5, 7.5, 15, 22.5, 30, 37.5°C min^-1)에 따른 반응속도상수가 도출되었다. 1차원 시뮬레이션 분석을 통하여 바이오매스 내부 온도를 예측하였으며 앞서 도출된 반응속도 상수를 이용하여 질량감소량이 예측되었다. 질량감소량 실험 및 시뮬레이션 결과 평균 r²=0.97로 상관관계를 나타내고 있으며 공정온도별 평균제곱근오차(Root Mean Square Error, RMSE)가 200°C-0.0165, 230°C-0.0191, 270°C-0.0207로 나타났다. 공정온도 증가에 따라 정확도가 감소되었으며, 이는 고온의 실험조건에서 발생되는 비응축가스와 온도변화에 의한 열분해 특성에 기인한 것으로 판단된다. 최종적으로 더 나아가서 질량감소 모델을 통한 발열량 예측을 위한 분석이 이루어져야한다.

청소년들의 최대 골량 향상을 위한 운동 가이드라인

민석기 ( Seok-ki Min ),오태웅 ( Taewoong Oh ),김상현 ( Sang Hyun Kim ),조진경 ( Jinkyung Cho ),정호연 ( Ho-yeon Chung ),박동호 ( Dong-ho Park ),김창선 ( Changsun Kim6 ) 한국운동생리학회(구 한국운동과학회) 2020 운동과학 Vol.29 No.1

PURPOSE: An increase in bone mineral density during adolescence increases resistance to fractures in older age. The Korean Society for Bone and Mineral Research and the Korean Society of Exercise Physiology developed exercise guidelines to increase the peak bone mass (PBM) in adolescents based on evidence through a systematic review of previous research. METHODS: Articles were selected using the systematic method, and the exercise guidelines were established by selecting key questions (KQs) and defining the effects of exercises based on evidence through a literature review for selecting the final exercise method. There were 9 KQs. An online search was conducted on articles published since 2000, and 93 articles were identified. RESULTS: An increase in PBM in adolescence was effective for preventing osteoporosis and fractures in older age. Exercise programs as part of vigorous physical activity (VPA) including resistance and impact exercise at least 5 to 6 months were effective for improving PBM in adolescents. It is recommended that resistance exercise is performed 10 to 12 rep·set^-1 1-2 set·region^-1 and 3 days·week^-1 using the large muscles. For impact exercises such as jumping, it is recommended that the exercise is performed at least 50 jumps·min^-1, 10 min·day^-1, and 2 days·week^-1. CONCLUSIONS: Exercise guidelines were successfully developed, and they recommend at least 5 to 6 months of VPA, which includes both resistance and impact exercises. With the development of exercise guidelines, the incidence of osteoporosis and fractures in the aging society can be reduced in the future, thus contributing to improved public health.

Production of Iron-Binding Peptides from Colostral Whey by Enzymatic Hydrolysis

Kim, Sang-Bum,Ku, Min-Jung,Cho, Won-Mo,Ki, Kwang-Seok,Kim, Hyeon-Shup,Nam, Myoung-Soo Korean Society for Food Science of Animal Resource 2010 한국축산식품학회지 Vol.30 No.6

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

Loop와 HPLC Purification 방법보다 더 높은 비방사능을 보여주는 카트리지 Methylation과 Purification을 이용한 손쉬운 [ ¹¹C]PIB 합성

이용석,조용현,이홍재,이윤상,정재민,Lee, Yong-Seok,Cho, Yong-Hyun,Lee, Hong-Jae,Lee, Yun-Sang,Jeong, Jae Min 대한핵의학기술학회 2018 핵의학 기술 Vol.22 No.2

$[^{11}C]PIB$는 베타아밀로이드($A{\beta}\;plague$)라는 변성 단백질에 결합하여 뇌의 기능과 기억력을 서서히 감퇴시키는 비가역적인 질환인 치매를 조기에 감별할 수 있는 대표적인 방사성의약품이다. 지금까지 많은 실험실에서 $[^{11}C]PIB$는 자동화합성장치에서 $[^{11}C]methyl\;iodide$나 $[^{11}C]methyl\;triflate$를 만든 다음 loop나 vial 방법을 사용하여 methylation을 한 다음 HPLC로 정제를 하는 것이다. 하지만 기존의 보고된 방법은 시간이 오래 걸리며, HPLC와 같은 복잡한 시스템을 필요로 하여 소규모 실험실에서 합성하기에 적합하지 않으며, 최종 product에서 에탄올 함량이 높다는 단점이 있었다. 이러한 단점을 보완하기 위하여 카트리지만을 사용하여 카트리지에서 methylation과 purification을 동시에 실시함으로써 합성 시간을 단축하고, 비방사능이 높고, 낮은 에탄올 함량을 가진 $[^{11}C]PIB$를 합성 가능한지 확인하고자 하였다. 가장 널리 사용하는 카트리지 6종(CM, HLB, Alumina, C18, tC18, tC18 environmental을 선택하여 screening test를 실시하였다. 6-OH-BTA-0 1 mg을 c-HXO에 녹인 다음 6개의 카트리지에 loading를 한 다음 0.5 M MSP(pH 5.1) 20 mL로 정제를 한 다음 최종 fraction을 받아서 analytical HPLC로 전구체 잔류량을 측정한 결과 hydrophobicity가 낮은 계열(CM, HLB, Alumina)의 카트리지에서는 완충액으로 정제를 하였을 때 잔류전구체의 양이 많았으나, 탄소함량이 많은 계열의 카트리지(C18, tC18, tC18 environmental)에서는 잔류전구체의 양이 CM, HLB, Alumina 카트리지에 비하여 상대적으로 적었다. 완충액의 정제 농도와 부피를 최적화 하기 위하여 screening test에서 가장 좋은 결과를 나타낸 C18 series cartridge를 가지고 추가 실험을 진행하였다. 인산완충액 농도를 10 mM, 20 mM, 30 mM, 40 mM, 50 mM, 250 mM, 500 mM로 변화시켰으며, 에탄올 함량은 20%와 30%로 하여 용출액을 분석하여서, $[^{11}C]PIB$를 카트리지로 합성하기 위한 최적의 조합은 tC18 environmental cartridge와 0.5 M MSP 20 mL인 것을 알 수 있었다. 기존에 보고된 방법과 cartridge를 비교한 결과, 합성시간에서는 각각 15 ~ 18min, 8 ~ 9 min이 소요되었으며, product activity는 각각 $4.1{\pm}1.4\;GBq$ (n=41), $3.8{\pm}0.9\;GBq$ (n=3), 방사화학적 수율(based on HPLC analysis of the crude product)에서는 $13.9{\pm}4.4%$ (n=41), $12.3{\pm}2.2%$ (n=3)로 별다른 차이가 없었으며, 비방사능에 있어서는 HPLC purification method가 $78.7{\pm}39.7\;GBq/{\mu}mol$ (n=41), cartridge method가 $420.6{\pm}20.4\;GBq/{\mu}mol$ (n=3)로 카트리지 방법이 기존 방법보다 더 좋은 결과를 나타내었다. 또한, 잔류 용매(c-HXO)도 vial or loop method와 별다른 차이가 없었으며, 에탄올 함량에 있어서는 70%(기존 방법)에서 30%(카트리지 방법)로 두 배 이상 함량이 적다는 사실을 알 수 있었다. 지금까지 알아본바와 같이 cartridge method는 reported method(HPLC purification)에 비하여 더 향상된 결과를 보여준다는 사실을 확인하였다. $[^{11}C]PIB$ synthesis has been performed by a loop-methylation and HPLC purification in our lab. However, this method is time-consuming and requires complicated systems. Thus, we developed an on-cartridge method which simplified the synthetic procedure and reduced time greatly by removing HPLC purification step. We compared 6 different cartridges and evaluated the $[^{11}C]PIB$ production yields and specific activities. $[^{11}C]MeOTf$ was synthesized by using TRACERlab FXC Pro and was transferred into the cartridge by blowing with helium gas for 3 min. To remove byproducts and impurities, cartridges were washed out by 20 mL of 30% EtOH in 0.5 M $NaH_2PO_4$ solution (pH 5.1) and 10 mL of distilled water. And then, $[^{11}C]PIB$ was eluted by 5 mL of 30% EtOH in 0.5 M $NaH_2PO_4$ into the collecting vial containing 10 mL saline. Among the 6 cartridges, only tC18 environmental cartridge could remove impurities and byproducts from $[^{11}C]PIB$ completely and showed higher specific activity than traditional HPLC purification method. This method took only 8 ~ 9 min from methylation to formulation. For the tC18 environmental cartridge and conventional HPLC loop methods, the radiochemical yields were $12.3{\pm}2.2%$ and $13.9{\pm}4.4%$, respectively, and the molar activities were $420.6{\pm}20.4GBq/{\mu}mol$ (n=3) and $78.7{\pm}39.7GBq/{\mu}mol$ (n=41), respectively. We successfully developed a facile on-cartridge methylation method for $[^{11}C]PIB$ synthesis which enabled the procedure more simple and rapid, and showed higher molar radio-activity than HPLC purification method.

Production of Iron-Binding Peptides from Colostral Whey by Enzymatic Hydrolysis

Sang Bum Kim,Myoung Soo Nam,Kwang Seok Ki,Hyeon Shup Kim,Min Jung Ku,Won Mo Cho 한국축산식품학회 2010 한국축산식품학회지 Vol.30 No.6

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at 100oC. Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at 50oC. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), β-lactoglobulin (β-LG), and α-lactalbumin (α-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not β-LG present in heated colostral whey. Alcalase completely eliminated BSA, β-LG, and α-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

조혈모세포이식 환자에서 침습성 진균 감염에 대한 Micafungin의 예방 효과 및 안전성

김시현,이동건,최수미,권재철,박선희,최정현,유진홍,이성은,조병식,김유진,이석,김희제,민창기,조석구,김동욱,이종욱,민우성,박종원 대한감염학회 2010 감염과 화학요법 Vol.42 No.3

Background: Micafungin, a potent inhibitor of 1,3-β-D-glucan synthase, is a novel antifungal agent of the echinocandin class. In vitro study showed that micafungin was effective against Aspergillus species as well as Candida species, but clinical data on the prophylactic efficacy against invasive fungal infections (IFIs) other than candidiasis are still lacking. Materials and Methods: We identified 60 consecutive adult hematopoietic stem cell transplantation (HSCT) recipients who received at least 3 doses of micafungin during neutropenic period. Micafungin was started as an alternative in patients who were intolerant or had adverse events (AEs) to primary prophylactic antifungal agents. We retrospectively reviewed the medical records and analyzed the efficacy and safety of micafungin for prophylaxis against IFIs. Results: The patients either had autologous (n=9) or allogeneic (n=51: 1 syngeneic, 24 sibling, 26 unrelated donor) HSCT. Itraconazole oral solution (n=58) was the most frequently used first line antifungal agent for prophylaxis and was administered for median 11 days. The most frequent cause of switch to micafungin was vomiting (n=42). The duration of neutropenia and micafungin administration was median 13 and 12 days, respectively. A successful outcome was achieved in 45 (75%) patients. Empirical antifungal therapy was initiated in 13 (22%) patients. There were 2 cases (3.3%) of breakthrough fungal infections which comprised a probable invasive pulmonary aspergillosis and a possible invasive fungal sinusitis. There was no case of invasive candidiasis. A total of 53 (88%) patients experienced at least one AE regardless of causality during micafungin administration. The most frequent AEs were hypokalemia, vomiting, diarrhea, and elevated serum aspartate aminotransferase or alanine aminotransferase. Among the aforementioned AEs, only 1 case of diarrhea could be classified as a probable relation with micafungin when causality was assessed. There was no AEs that caused discontinuation of micafungin. Conclusions: Micafungin seems to be a safe and effective agent for prophylaxis of IFIs including aspergillosis as well as candidiasis in HSCT recipients. However, further large, prospective, and randomized comparative studies are warranted for aspergillosis.

전북지방 젖소의 유방염 검색

조정곤,김종면,최민순,채효석,강명대,송희종 全北大學校 附設 畜産開發硏究所 1987 畜産開發硏究報告 Vol.1 No.-

A total of 444 quarters milk samples of 111 dairy cattle in Chonbuk area were examined for infection rete and causative agents of mastitis by "the laboratory procedures used in the Connecticut Mastitis Control Program (CMCP) and California mastitis Test (CMT)". The results obtained were as follows: 1. Of 444 samples, 39.2% had positive CMCP value and 24.4% positive CMT reaction. 2. One hendred and seventy four (39.2%) from 82 cattle (73.9%) were found to infected with mastitis. It was found that 8(1.8%0 of the infected quarters were clinical mastitis and all of the rest were subclinical mastitis. 3. The main causative agents were found to Staphylococcus aureus (63 quarters), Streptococcus agalactiae (56 quarters), non-Str. agalactiae streptococci (54 querters), Escherichia coli (19 quaters), the actual total number of quarters detected as mastitis would be 174, as 18 of these quarters showed multiple infection with two different organisms. 4. Having examined the number of infection quarter per head of mastitis in dairy cattle sampling, major finding were that the average number of infection quarters to total dairy cattle exemined was 1.57 quarters, and that of the infected cattle was 2.1 quarters. Infected quarters in cattle with 1, 2, 3 and 4 were noted 27(32.9%), 28(34.1%), 17(20.7%), and 10(12.3%), respectively.

Mo 화학기상증착에 있어서 불순물 농도에 미치는 증착조건의 영향

배상석,서성교,홍은식,김승모,조미정,한혜정,이두성,김세훈,민석홍 국립7개대학공동논문집간행위원회 2001 공업기술연구 Vol.1 No.-

The thermal decomposition process of Mo(CO)_6 on chemical vapor deposition was investigated by analyzing the effects of deposition temperature, pressure, and reaction gas on the phase change of deposited films. Mo_2C was deposited at or below 350℃ due to the incompleteness of thermal decomposition of Mo(CO)_6, but Mo films was successfully deposited at 400℃ or higher temperatures. The variation of deposition pressure did not change the dependence of decomposition process on deposition temperature. The activation energy of surface reaction was 5.8 ㎉/mole.

Memory 소자 응용을 위한 BST(Ba_xSr_1-_xTiO_3) 강유전체 박막과 전극과의 계면특성

정민재,조정희,홍석민,김호건,김옥경 漢陽大學校 工學技術硏究所 1997 工學技術論文集 Vol.6 No.1

BaxSr1-xTiO3 powders were prepared by changing stoichiometry of Ba and Sr. After they were calcined and sintered at 1,200℃ and 1,300℃ respectively, BST sputtering targets were made in 3inch mould. For MIM structure capacitors. Pt-based structures such as Pt/TiN/SiO2/Si, Pt/Ti/Si3N4/Si, Pt/SiO2/Si, Ru/SiO2/Si and Ru/Si3N4/Si were used for bottom electrodes, and subsequently, the BaxSrl-xTiO3 thin films were sputtered on them. After the analysis of their structures by XRD, Al was evaporated on the BST films for MIM capacitor. We found that the structures of the films showed good crystallinity above 550℃ from the results of XRD measurements. The largest dielectric constant of films was obtained with 0.7mol% of Ba. The electric properties of the capacitors were very good with Pt/TiN/SiO2/Si electrodes.

국내 상수원수의 유기물 특성에 따른 소독부산물 생성능

염철민,변석종,조순행,윤제용 대한상하수도학회 2003 상하수도학회지 Vol.17 No.1

This study was conducted to investigate the characteristics of disinfection by-products formation potential (DBPFPs) of dissolved organics. Dissolved organics in raw water were separated into two fractions ((1) hydrophilic and (2) hydrophobic) for the measurement of DBPs. Three types of DBPs (trihalomethanes (THMs), haloacetic acids (HAAs), and total organic halides (TOX)) were measured at 3days and 7days incubation time. Sample waters were collected from the Han River and the Wonchun Reservoir. Two major findings are as follows. First, THMFPs/DOC, HAAFPs/DOC and TOXFPs/DOC in the hydrophilic organic component had a level of lower value than those of the hydrophobic organic component. Brominated THMs and bominated HAAs were not found in the chlorinated hydrophobic organic component. Second, the magnitude of HAAFPs/DOC were higher than that of THMFPs/DOC in both hydrophilic and hydrophobic organic components. This results support the reported observation that HAAs formations were higher than that of THMs in chlorinated drinking water. THMFPs and HAAFPs comprised 53-91% of TOXFP.