• 한국토양비료학회지
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• 제37권5호
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• pp.350-355
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• 2004

본 연구는 분무경 방식을 이용한 arbuscular 균근균 접종원의 대량배양증식을 위하여 기주식물의 종류와 분무양액의 P 농도 등에 따른 균근감염율 및 감염양상 변화 등을 비교하였다. 기주식물 선발에서는 고구마와 토마토가 수단그라스와 질경이에 비해 우수하였다. 또한 인산농도가 5 또는 $10{\mu}M$ 보다 $20{\mu}M$의 수준으로 높아질수록 뿌리의 생성량이 많아진 반면, 뿌리의 균근감염은 인산농도가 낮을수록 높고, 하부 뿌리로 갈수록 arbuscular 균근균 감염율이 낮아지는 경향을 보였으며 감염율은 18.6~26.0% 범위였다. 16주후의 포자형성을 조사한 결과 신선중 1 g 당 500개의 포자가 형성되었고, 분무생육상당 생산된 포자는 총830.479개였다.

• 공업화학
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• 제24권4호
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• pp.382-390
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• 2013

소다석회 조성의 폐 병유리를 대상으로 효율적인 재활용방안을 찾기 위해서 발포화에 적절한 조성의 조절을 통해 직접 보온단열재 발포유리블럭을 제조할 수 있는 공정을 조사하였다. 폐 병유리의 직접 발포화를 위해 첨가되는 성분 및 조성은, 폐 유리분말 100중량부에 대하여 $SiO_2$ 10중량부, $Na_2SO_4$ 0.5중량부, $B_2O_3$ 3.0중량부, 그리고 발포제로서 카본 블랙류 탄소재 0.3중량부이다. 발포공정은 턴넬키른에서 진행하며, 발포소성 조건은 폐 유리분말의 입도는 -325 mesh, 발포소성온도는 $830{\sim}850^{\circ}C$, 발포시간은 30~35 min이 바람직하다. 상기 조건하에 제조된 발포체는 밀도가 $0.17{\sim}0.21g/cm^3$, 열전도도 $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, 수분 흡수율 1.1~1.5%, 압축강도는 $20{\sim}30kgf/mm^2$의 물성을 나타내었다.

• Environmental Analysis Health and Toxicology
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• 제24권3호
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• pp.251-259
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• 2009

This study was conducted to measure the concentration of PCBs in pine needles and soil in urban (Seoul, many artificial sources of PCBs), semi-rural (Anseong, small town located below Seoul in wind direction) and rural areas (Jincheon, rarely artificial sources of PCBs) in which the artificial production amount of PCBs are different. The total PCBs concentrations in pine needles, which did not show big difference in three sampling sites, were 107.5 pg/g (urban), 94.8 pg/g (semi-rural) and 78.8 pg/g (rural) respectively. The low chlorinated PCBs were major component in pine needles and the PCBs congener concentration profile of each sampling area were similar each other, and the octanol-air partitioning coefficient, Koa, highly correlated with the PCBs concentrations in pine needles. The total PCBs concentrations in soil which did show big difference in three sampling sites, were 830.0 pg/g (urban), 314.1 pg/g (semi-rural) and 136.5 pg/g (rural) respectively. The high chlorinated PCBs were major component in soil and the PCBs congener concentration profile of each sampling area were similar each other. There was no similarity between the PCBs concentration of pine needles and those of soil at each site, because of the different mechanism of deposition and volatilization processes of PCBs. The total PCBs concentrations of 2009 became 12.9 times lower than those of 2001. The reduce rate of PCB 28 was the greatest.

• 대한화장품학회지
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• 제40권3호
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• pp.269-278
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• 2014

2013년 1월에서 8월 사이에 전국에서 유통 중인 립스틱, 립글로스, 립밤, 파운데이션, 아이라이너 등 색조화장품 121개 제품에서 납, 카드뮴, 비소, 크롬, 안티몬, 니켈, 구리 및 코발트의 농도 측정과 국산 및 수입산, 유형별, 색상별로 비교함으로써 이와 관련된 분야의 기초자료를 제공하고자 본 연구를 시행하였다. 분석된 전체 색조화장품의 중금속 평균 농도는 납 $0.663{\mu}g/g$, 카드뮴 $0.010{\mu}g/g$, 비소 $0.056{\mu}g/g$, 크롬 $1.144{\mu}g/g$, 안티몬 $0.008{\mu}g/g$, 니켈 $0.405{\mu}g/g$, 구리 $0.319{\mu}g/g$ 및 코발트 $0.108{\mu}g/g$으로 측정되었다. 국산 및 수입산 색조화장품은 통계적으로 유의한 차이를 보였으며(p < 0.05), 수입산이 크롬을 제외한 7개 금속에서 국산보다 높게 검출되었다. 색조화장품의 유형에 따른 중금속 농도는 통계적으로 유의한 차이를 보였으며(p < 0.05), 립스틱에서 크롬 $1.430{\mu}g/g$, 납 $0.616{\mu}g/g$ 그리고 니켈 $0.385{\mu}g/g$이 파운데이션에서 납 $1.155{\mu}g/g$, 크롬 $1.023{\mu}g/g$이 가장 높은 농도를 보였으며, 아이라이너에서는 크롬 $1.424{\mu}g/g$, 니켈 $0.830{\mu}g/g$이 가장 높은 농도를 나타내었다. 색조화장품의 색상별 중금속 농도는 통계적으로 유의한 차이를 보였으며(p < 0.05), 갈색의 화장품은 크롬, 니켈과 구리가 높은 평균 농도를 보였고, 아이보리색의 화장품은 납과 크롬이 핑크색의 화장품은 크롬과 납이 높은 평균 농도를 나타내었다.

• Journal of Dairy Science and Biotechnology
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• 제38권3호
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• pp.142-145
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• 2020

Enterococcus faecalis CAUM157, isolated from raw cow's milk, is a Gram-positive, facultatively anaerobic, and non-spore-forming bacterium capable of inhabiting a wide range of environmental niches. E. faecalis CAUM157 was observed to produce a two-peptide bacteriocin that had a wide range of activity against several pathogens, including Listeria monocytogenes, Staphylococcus aureus, and periodontitis-causing bacteria. The whole genome of E. faecalis CAUM157 was sequenced using the PacBio RS II platform, revealing a genome size of 2,972,812 bp with a G+C ratio of 37.44%, assembled into two contigs. Annotation analysis revealed 2,830 coding sequences, 12 rRNAs, and 61 tRNAs. Further, in silico analysis of the genome identified a single bacteriocin gene cluster.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.904-905
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• 2008

In this paper, a novel 60kV, 300A, 3kHz pulsed power supply based on IGBT stacks is proposed. Proposed scheme consists of series connected 9 power stages to generate maximum 60kV output pulse and 15kW series resonant power inverter to charge DC capacitor voltage. Each power stages are configured as 8 series connected power cells and each power cell generates up to 830VDC, 300A pulses. Finally pulse output voltage is applied using total 72 series connected IGBTs. The synchronization of gating signal is important of series operation of IGBTs. For gating signal synchronization, full bridge inverter and pulse transformer generates on-off signals of IGBT gating and specially designed gate power circuit was used.

• 한국가금학회지
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• 제28권3호
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• pp.275-281
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• 2001

본 시험은 키토산 및 녹차의 급여가 산란계의 사양성적 및 혈액과 난황의 콜레스테롤 수준에 미치는 영향을 관찰하기 위하여 실시하였다. 시험은 옥수수-밀기울 위주 사료로 처리당 3반복 반복당 30수씩 60주령 갈색 산란계를 총 360수 공시하여 8주간에 걸쳐 키토산을 0.15%를 첨가(T1), 녹차잎을 0.15% 첨가 (T2) 및 키토산과 녹차잎을 각각 0.15% 첨가 (T3)하여 수행하였다. 사료섭취량은 대조구가 약 830g으로 가장 낮았고, 처리구에서는 T2구가 낮은 경향을 보였으나, 산란율은 대조구의 52.6%에 비하여 T1구가 55.7%로 높은 경향을 보였으며, T2(59.3%) 및 T3구 (58.4%)는 유의적 (P<0.05)으로 높았다. 난중은 대조구가 63.8g으로 T1구의 62.3g에 비하여 높은 경향이었으나, T2및 T3구의 65g에 비하여 낮은 경향을 나타냈다. 혈중 콜레스테롤 함량은 시험 개시 시에 비하여 8주후에 처리구 (T1, T2 및 T3)에서 114∼123mg/dl로 유의적으로 감소하였으며 (P<0.05), 처리간 혈중 콜레스테롤 함량은 T2가 다른 처리구에 비하여 낮은 경향을 보였다. 그러나 난황 콜레스테롤 농도에는 키토산과 녹차의 첨가가 영향을 미치지 못하였다.

• 한국전기전자재료학회논문지
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• 제19권7호
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• pp.636-643
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• 2006

Si-C materials were synthesized by the heating the mixture of silicon and polyvinylidene fluoride (PVDF). The electrochemical properties of the Si-C materials as the high capacitive anode materials of lithium secondary batteries were evaluated by the galvanostatic charge-discharge test through 2032 type $Si-C{\mid}Li$ coin cells. Charge-discharge tests were performed at C/10 hour rate(C = 372 mAh/g). Initial discharge and charge capacities of $Si-C{\mid}Li$ cell using a Si-C material derived from PVDF(20wt.%) were found to be 1,830 and 526 mAh/g respectively. The initial discharge-charge characteristics of the developed Si-C electrode were analyzed by the electrochemical galvanostatic test adopting the capacity limited charge cut-off condition(GISOC). The range of reversible specific capacity IIE(intercalation efficiency at initial discharge-charge) and IICs(surface irreversible specific capacity) were 216 mAh/g, 68 % and 31 mAh/g, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.350-351
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• 2005

The electrochemical behavior of Si-C material synthesized by heating the mixture of silicon and polyvinylidene fluoride (PVDF). Coin cells of the type 2025 were made using the synthesized material and the electrochemical studies were performed. Si-C/Li cells were made by using the developed Si-C material. Charge/discharge test was performed at 0.1C hour rate. Initial charge and discharge capacities at Si-C material derived from 20 wt.% of PVDF was found to be 1,830 and 526 mAh/g respectively. Initial charge/discharge characteristics of the electrode were analyzed. The level of reversible specific capacity was about 216 mAh/g at Si-C material derived from 20 wt.% of PVDF, IIE, intercalation efficiency at initial charge/discharge, was 68 %. Surface irreversible specific capacity was 31 mAh/g, and average specific resistance was 2.6 ohm*g.

• 한국축산식품학회지
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• 제39권5호
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• pp.820-830
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• 2019

Most consumers consider yogurt to be a healthy food because it contains probiotic microorganisms. Although a plethora of commercially produced yogurts exists, nutritional and functional aspects of the commercial yogurts have not been well characterized. In this study, the microbiological and physicochemical properties of popular drinking yogurts in Korea were extensively characterized. The viability of lactic acid bacteria, including lactobacilli and bifidobacteria, varied between yogurt samples. These lactobacilli and bifidobacteria showed effective antimicrobial activities against foodborne pathogenic bacteria. Unlike the titratable acidity and pH, the soluble solids content varied between yogurt samples. All the yogurt samples contained high levels of potassium (average 143.53 mg/100 g) and calcium (average 133.92 mg/100 g), as well as phosphorus and sodium. Lactose, fructose, and glucose were the major sugar components in most yogurt samples, whereas the levels of sucrose and maltose were relatively low. Among several organic acids analyzed in the yogurt samples, lactic acid (average 767.67 mg/100 g) and citric acid (average 170.91 mg/100 g) were the most predominant. Taken together, this study provides preliminary information about the nutritional and functional characteristics of commercially available drinking yogurts.