• 자원리싸이클링
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• 제19권1호
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• pp.33-39
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• 2010

화력발전소에서 배출되는 바닥재와 준설토를 70:30(wt%)로 혼합하고 이를 $6{\pm}2mm$ 크기 구형으로 성형 및 로터리 킬른에서 $1125^{\circ}C$/15 min으로 소성한 뒤, 그 물리적 특성을 평가함으로써 오염 토양을 복원하는데 사용되는 흡착제로의 적용 가능성을 분석하였다. 제조된 소결체(BD)는 100 ${\mu}m$ 이상의 거대 기공 및 10 ${\mu}m$ 이하의 미세기공을 모두 가지고 있었으며, 비표면적, 기공율 그리고 공극율은 각각 $12.0m^2/g$, 30.1%그리고 38.2%이었다. BD 소결체를 한번 분쇄한 시편(BD-C)은 종횡비$\fallingdotseq$2의 부정형이었으나, 부피비중 및 기공크기 분포는 BD와 비슷한 값을 나타내었다. 한편 BD-C 시편의 비표면적, 기공율 그리고 공극율은 BD에 비해 더 우수한 값을 나타내었는데 이는 내부에 존재하던 폐기공(closed pores)이 분쇄과정에서 개기공(open pores)으로 변환되면서 겉보기 부피가 감소했기 때문이다. 제조된 소결체의 영 전하점(IEP)는 약 pH=5이었고 따라서 미생물을 소결체에 결합시킬 때 반응용액의 최적 pH를 알 수 있었다. 본 연구에서 제조된 소결체는 오염 토양 복원에 사용되는 흡착제로의 적용이 가능하며, 더구나 측정된 데이터를 이용하여 BD와 BD-C를 적절한 비율로 혼합하면 적용 상황에 따라 다른 공극율, 기공율 등의 요구 조건을 최적으로 맞출 수 있을 것으로 기대된다.

• 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.

• Journal of Biosystems Engineering
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• 제35권4호
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• pp.239-243
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• 2010

Biodiesel (BD) can be effectively used as an alternative fuel in diesel engines. However, BD may affect the performance and exhaust emissions in diesel engines because it has different physical and chemical properties from diesel fuel such as viscosity, compressibility and so on. To investigate the effect of injection timing on the characteristics of engine performance and exhaust emissions with BD in an indirect injection diesel engine, BD derived from soybean oil was applied in this study. The engine was operated at six different injection timings from TDC to BTDC $12^{\circ}CA$ and five loads at various engine speeds. Below BD 30, there's similar trend compared with diesel fuel. But, the best injection timing was $4{\sim}6^{\circ}CA$ retarded compare with diesel fuel using BD 30. When the fuel injection timing was retarded, better results were showed, which may confirm by advantages of BD.

• 한국어류학회지
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• 제28권2호
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• pp.125-133
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• 2016

전 세계 상어류 (상어구 Selachii)는 약 510종이 유효하고, 우리나라에서는 8목 19과 30속 43종이 보고되었다. 우리나라에 분포하는 상어류 43종 모두가 세계자연보존연맹 적색목록 (IUCN Red List)에 등재되었으며, IUCN 등급별 종 수 및 비율은 위기 (EN) 상태 1종 (2.3%) (vs. 전 세계 15종, 3.2%), 취약 (VU) 11종 (25.6%) (vs. 48종, 10.3%), 준위협 (NT) 10종 (23.3%) (vs. 67종, 14.4%), 관심대상 (LC) 9종 (20.9%) (vs. 115종, 24.7%), 정보부족 (DD) 12종 (27.9%) (vs. 209종, 44.9%)이었으며, 위급 (CR)에 해당하는 종은 전 세계에는 11종 (2.4%)인데 우리나라에 서식하는 종은 없었다. 한반도 해역에 분포하는 상어류 중 멸종우려 (Threatened)에 해당하는 12종과 적색목록 범주와 평가는 다음과 같다: 홍살귀상어 (EN, A2bd+4bd), 고래상어 (VU, A2bd+3d), 돌묵상어 (VU, A2ad+3d), 백상아리 (VU, A2cd+3cd), 청상아리 (VU, A2abd+3bd+4abd), 환도상어 (VU, A2d+4d), 횐배환도상어 (VU, A2bd+3bd+4bd), 흉상어 (VU, A2bd+4bd), 귀상어 (VU, A2bd+3bd+4bd), 곱상어 (VU, A2bd+3bd+4bd), 전자리상어 (VU, A2d+4d), 범수구리 (VU, A2d+4d). 멸종 위기 야생동 식물종 국제교역협약 (CITES) 부속서에 전 세계의 연골어류 중 18종이 등재되었으며, 우리나라 해역에 분포하는 상어류는 고래상어, 돌묵상어, 백상아리, 홍살귀상어, 귀상어 등 5종이 부속서 II에 포함되었다. 북태평양에 분포하는 곱상어의 학명 Squalus acanthias는 S. suckleyi로, 북서태평양의 모조리상어는 S. megalops에서 S. brevirostris로 변경되었다.

• 대한임상검사과학회지
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• 제38권3호
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• pp.189-195
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• 2006

Behcet's disease (BD) is a chronic, multisystemic disorder which is more frequently seen in the Mediterranean basin, Middle East, and Far East. The causes and pathogenesis of BD are unknown although many possibilities are being investigated. The diagnosis of BD is based on clinical manifestations because there are no pathognomonic laboratory tests. So, the purpose of this study was to examine the prevalence of HLA-B51 in patients with BD. We used the whole blood of 33 patients diagnosed with BD at Chosun University Hospital from August 2003 to January 2006. For the HLA-B51 test, we extracted the DNA from the whole blood of 33 BD patients, and we investigated it through the nested PCR method. Data were analyzed using the SPSS/PC 10.0. The frequencies of gender of the 33 cases diagnosed as BD were male 13 (39.4%) and female 20 (60.6%). The frequencies of age group of the 33 cases diagnosed as BD were 20 yrs 8 (24.2%), 30 yrs 12 (36.4%), 40 yrs 8 (24.2%), 50 yrs 1 (3.0%), and 60 yrs and 70 yrs 2 (6.1%), respectively. The frequencies of HLA-B51 of the 33 cases diagnosed as BD were HLA-B51-negative 18 (54.5%) and HLA-B51-positive 15 (45.5%). In conclusion, BD occurred more often in women than men (1: 1.53), and the mean age of the BD patients was 39.8 years old. HLA-B51 was positive in 45.5% of patients with BD, and was statistically significant in age (p<0.05).

• 대한기계학회논문집B
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• 제36권7호
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• pp.745-752
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• 2012

디젤엔진은 바이오연료 적용을 위한 엔진으로서 가솔린엔진과 비교해 사용연료가 바이오연료와 유사한 높은 세탄가를 가지며, 가솔린엔진과 달리 점화계통 장치의 불필요 등 기존 엔진의 개조비용 등에서 유리한 장점이 있다. 따라서 본 연구에서는 상용 디젤 엔진의 커먼레일 분사시스템을 사용하여 바이오연료인 식물성 팜유의 분무거동특성을 해석하고, 그 결과를 기존의 디젤엔진 연료인 경유와 비교 분석하였다. 실험변수로서는 분사압력과 경유에 대한 바이오디젤 연료의 혼합비율(BD3, BD5, BD20, BD30, BD50, BD100)을 달리하였다. 분사압력은 500bar, 1000bar, 1500bar 및 1600bar로 설정하고 분사기간은 $500{\mu}s$로 동일하게 하였다. 본 연구의 결과로서, 분사압력이 동일한 경우 사용한 바이오디젤 연료의 혼합비 변화에 대한 거시적 분무거동특성(분무선단도달거리 및 분무각)의 변화는 뚜렷하지 않았다. 특히 분무각의 경우 본 연구의 모든 실험조건에 있어서 약 $15^{\circ}$의 값을 나타내었다.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.213-218
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• 1989

Cloning을 위한 host와 vector의 이용 가능성을 타진하기 위해 호알칼리성 Bacillus속 K-17을 host로, pUB110과 pBD64를 vector로 사용하여 Bacillus속 K-17의 protoplast 형질전환조건을 검토하였다. 원형질체의 형성은 200$\mu\textrm{g}$/$m\ell$의 Iysozyme 을 처리하였으며, 원형질체 형성의 최적 온도, PH및 배양시간은 각각 4$0^{\circ}C$, 7.0 및 4시간으로 나타났다. 원형질체는 DM3 재생배지에서 재생시켰으며 0.8% agar, 0.5M sodium succinate 농도에서 가장재생이 좋았다. 형질전환시 PEG의 농도는 40%(w/v) PEG 6,000 30%(v/v)가 최적으로 나타났다. 형질전환체의 특성을 조사한 결과, plasmid 안정성은 pUB110이 pBD64보다 더 안정하였으며, 최대 효소활성은 비슷하였지만 효소 분비시간은 pUB110 은 2.5일, pBD64의 경우는 3일로 Bacillus속 K-17의 2일에 비해 약간 지연되었다.

• 한국환경보건학회지
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• 제30권4호
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• pp.301-307
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• 2004

1,3-butadiene(DB) is a well-established rodent carcinogen, and a probable carcinogen to humans. This study was investigated the formation of hemoglobin adduct in ICR female mice inhaled with BD for 3 weeks (5 hr/day, 5 days/week). Body weights of mice were significantly low from onward day 4 or 9 of exposure comparing the control. Hemoglobin adducts formed by DB exposure were (N-2-hydroxy-3-butenyl) valine (HB Val adduct) and (N-2,3,4-trihydroxy-butyl)valine(THB Val adduct). The levels of HB Val adducts were 1.8, 3.7 and 6.2 pmol/mg globin for the 500 ppm BD inhalation group, and 5.7, 7.4 and 16.0 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. The levels of THBVal adducts were 32.0, 42.0 and 55.0 pmol/mg globin for the 500 ppm DB inhalation group, and 67.8, 72.7 and 83.5 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. Ratios of THBVal and HBVal adducts were higher at earlier exposure period and lower concentration. Ratios on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week were 17.8, 11.4 and 8.87 for the 500 ppm BD inhalation group, and 11.9, 9.8 and 5.2 for the 1000 ppm BD inhalation group, respectively. In conclusion, THB Val and HB Val adducts were the important hemoglobin adducts in ICR female mice inhaled with BD, and the latter was more appropriate biomarker than the other for biological monitoring of BD exposure.

• 한국생활과학회지
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• 제19권5호
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• pp.897-904
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• 2010

This study assessed the quality of barley Dasik manufactured, according to traditional methods, with various levels of Maesil (Prunus mume) extracts at weight percentages of 0% (BD1), 10% (BD2), 20% (BD3), 30% (BD4), 40% (BD5). The Dasik were analysed with proximate analysis, a sugar content analysis, Hunter's color value test, mechanical characteristics test and a sensory evaluation. Increased ratios added Maesil extracts led to the moisture content, crude ash, and crude fat to significantly increase (p<.001). 10% (BD2) had significantly higher levels of crude protein (p<.01). Sugar contents was highest in 0% (BD1) and decreased as the amount of added Maesil extracts increased. This increase also led to higher L-values and b-values of chromaticity (p<.001) and the a-value of 0% (BD1) was significantly higher than the sample groups (p<.001). Changes in texture profile analysis, hardness and gumminess values were highest in the control group and the values of those in the sample group decreased with increasing amounts of Maesil extract (p<.001). It should be noted that, among the samples evaluated, barley Dasik that contained 10% Maesil extract (BD2) had the highest commercial value.

• Animal Bioscience
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• 제37권5호
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• pp.875-882
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• 2024

Objective: An experiment was conducted to study the effect of supplementing DL methionine (DL Met) at graded concentrations on performance, carcass variables, immune responses and antioxidant variables in broiler chicken fed folic acid (FA) fortified (4 mg/kg) low-methionine diet. Methods: A basal diet (BD) without supplemental DL Met, but with higher level (4 mg/kg) of FA and a control diet (CD) with the recommended concentration of methionine (Met) were prepared. The BD was supplemented with DL Met at graded concentrations (0%, 10%, 20%, 30%, 40%, and 50% supplemental DL Met of CD). Each diet was fed ad libitum to 10 replicates of 5 broiler male chicks in each from 1 to 42 d of age. Results: Body weight gain (BWG) reduced, and feed conversion ratio (FCR) increased in broilers fed low-Met BD. At 30% and 20% inclusion of DL met, the BWG and FCR, respectively were similar to those fed the CD. Similarly, supplementation of 10% DL Met to the BD significantly increased ready to cook meat yield and breast meat weight, which were similar to those of the CD fed broilers. Lipid peroxidation reduced, the activity of antioxidant enzymes (GSHPx and GSHRx) in serum increased and lymphocyte proliferation increased with increased supplemental DL Met level in the BD. The concentrations of total protein and albumin in serum increased with DL Met supplementation to the BD. Conclusion: Based on the data, it can be concluded that supplemental Met can be reduced to less than 50% in broiler chicken diets (4.40, 3.94, and 3.39 g/kg, respectively in pre-starter, starter and finisher phases) containing 4 mg/kg FA.