• 한국미생물·생명공학회지
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• 제23권3호
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• pp.346-351
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• 1995

To produce ethanol from Jerusalem artichoke powder efficiently, Kluyveromyces marxianus F043 cells were encapsulated in 2% sodium alginate and were cultured in a countinuous reactor to investigate the fermentation properties. Immobilized K. marxianus F043 cells were activated for 48 hours in a fermentor for continuous ethanol production. The culture in a CSTR using a Jerusalem artichoke substrate treated with 2% cellulase showed a decrease in ethanol concentration and an increase in residual saccharide concentration with a increasing dilution rate. Optimum conditions for high ethanol productivity and low residual saccharide output were clarified to be given at a dilution rate of 0.2 h$^{-1}$ and a Jerusalem artichoke medium concentration of 75 g/l. Ethanol productivity of 3.1 g/l-h and saccharide utilization of 62.6% were obtained under the optimum condition. When the fermentation was performed for 3 weeks under these conditions, the effluent medium showed stable ethanol concentrations of 16.3 - 17.9 g/l and viable cells of 6.60-7.16 log cells/ml without contamination. Trace amounts of methyl, n-propyl, iso-butyl, isoamyl alcohols besides ethanol were detected.

• 대한화학회지
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• 제36권2호
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• pp.282-286
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• 1992

Polyacrylic acid와 polymethacrylic acid를 N-hydroxysuccinimide에 반응시켜 poly(N-acryloxysuccinimide)와 poly(N-methacryloxysuccinimide)를 합성하고, 이것과 cephradine을 반응시켜 polyacryloylcephradine과 polymethacryloylcephradine을 합성하였다. 이들 중합체약의 항균성을 2단계 희석법에 의하여 최소 발육저지 농도로서 조사하였다. Polyacryloylcephradine 중합체에 대한 최소 발육저지 농도는 Staphylococcus aureus ATCC 25923, Staphylococcus aureus FDA 209P, Bacillus subtilis ATCC 6633, Bacillus licheniformis ATCC 14580, Escherichia coli BE 1186 및 Salmonella typhimurium TV 119 균주들에 항균성이 대체적으로 우수하였다. Polymethacryloylcephylococcus aureus FDA 209P, Bacillus subtilis ATCC 6633, Escherichia coli BE 1186 및 Salmonella typhimurium TV 119 균주들에 대해서 항균력을 보여주었다.

• 대한환경공학회지
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• 제37권4호
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• pp.240-245
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• 2015

본 연구에서는 대전광역시 동구를 중심으로 공중화장실에 대하여 악취강도를 공기희석관능법과 기기분석을 통하여 공중화장실관리 및 악취저감대책 수립에 기초자료로 제공하고자 하였다. 악취희석배수는 소변기실에서 10~669, 대변기실에서는 31~464까지 다양하게 나타났다. 한편 민원이 발생할 수 있는 악취강도 2.5도 이상의 악취가 발생하는 곳은 6개소(33%)로 조사되었다. 수세식 발효식 재래식처리방식의 대변기실과 설치년도에 따라 악취강도는 차이가 있으나, 화장실 면적은 차이가 없다. 악취원인물질 확인을 위한 6개 공중화장실을 대상으로 기기분석결과 NH3 최대농도는 2.04 ppm, 평균농도는 0.67 ppm이며, $H_2S$, $CH_3SH$, $(CH_3)_3N$는 검출되지 않았다. 발효식과 재래식공중화장실에는 비누, 방향제, 쓰레기통이 없었다. 화장지는 수세식 화장실의 50%에만 있었다.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.378-385
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• 1997

Cation motive ATPases on cell membranes of Helicobacter pylori were investigated using everted membrane vesicles. Latent ATPases could be ascertained from aggregated vesicle using N, N-dimethylformamide (DMF) and Triton X-100. By contrast, ultrasonication or chloroform treatments caused membranes to be disrupted, resulting in an alteration of sensitivities against azide or vanadate. Considerable amounts of vanadate-sensitive enzymes were identified from vesicle micelles, prepared by the dilution method. These were activated in the presence of either $Ni^{2+}\;or\;NH_4^+$. From studies employing H. pylori intact cell systems, we found that ATPase expression of this bacterium was markedly dependent upon air composition. It was interesting that cellular expression of $Ni^{2+}$- or $NH_4^{+}$-motive ATPases was significantly affected by extracellular pH, suggesting that these unique enzymes may physiologically be involved in cellular $Ni^2$ import and $NH_4^+$ export, respectively.

• 한국식품과학회지
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• 제4권3호
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• pp.200-205
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• 1972

Candida tropicalis KIST 351을 $2.5{\ell}$ 및 $28{\ell}$ 발효조에시 배양하여 석유 유분별자화능, 석유탄화수소기질의 즉차적 유가배양(流加培養), 폐배지(spent medium)의 재사용 및 연속배양 등 배양기술적인 기초문제를 검토한 바 그 개요는 다음과 같다. (1) 각종 경유유분(LGO, HGO, VGO, Diesel oil, SP(E), HGO-wax, L/M-wax)에 있어저 균체농도는 $11{\sim}15g/{\ell}$, 경유에 대한 수율은 $10{\sim}12%$, 소비된 n-paraffin에 대한 수율은 $77{\sim}82%$였다. (2) 동 균주를 유가배양 함으로써 균체들 배지에 대하여 $18.9g/{\ell}$, 경유에 대한 수율을 13%로 향상시킬 수 있었다. (3) 폐배지는 탄화수소를 유화시키고 증식을 촉친하는 효과를 가지고 있었으며 $Mg^{++}$를 보충하지 않었을 때는 20%, 보충하였을 때는 50%까지 회수 재 사용 할 수 있었다. (4) 균체생산을 위한 연속배양의 최적희석율은 $D=0.1{\sim}0.125\;hr^{-1}$의 범위내에 있으며, 이때의 균체농도는 약 $8g/{\ell}$였고, $D=0.125\;hr^{-1}$에서의 균체생산속도는 $1.0\;g/{\ell}/hr$로써 최대치에 달하였다. 소비된 경유 중의 n-paraffin에 대한 균체수율은 $D=0.1\;hr^{-1}$에서 0.94로써 최대치를 보였다. 그러나 희석율 $0.1\;hr^{-1}$에서 공급된 n-paraffin의 약 24%가 기질로써 소비 되지 않었으므로 이에 대한 적절한 대책이 요구된다.

• 한국식품위생안전성학회지
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• 제11권4호
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• pp.299-306
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• 1996

6-[(N-3,4-Dibromophenyl)amino]-7-chloro-5,8-quinolinedione(FCK13) was tested for antifungal activities. The MIC values were determined by the two-fold dilution method. The therapeutic potential of RCK13 had been assessed in comparison with ketoconazole and fluconazole against systemic infections with candida albicans in normal mice. RCK13 had ED50,0.80$\pm$0.21 mg/kg but ketoconazole had ED50, 8.00$\pm$0.73 mg/kg respectively. And administered RCK13 at the ED50 for 14 days improved survival rates as well as ketoconazole. Acute oral toxicity studies of RCK13 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK13 were low and LD50 values were over 2,850 mg/kg in ICR mice. The genotoxicities of RCK13 had been evaluated. RCK13 was negative in Ames test with Salmonella typhimurium and chromosomal aberration test in CHL cells. The clastogenicity was tested on the RCK13 with in vivo mouse micronucleus assay. RCK13 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK13 has no genotoxic potential under these experimental conditions.

• 한국환경과학회지
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• 제8권4호
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• pp.443-449
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• 1999

This paper describe the working of algal culture system under batch and continuous feeding effluents in biological treatment process. The main objective of this study was the determination of fundamental opeating parameters such as dilution rates, light intensity, biomass concentration, nutrients contents, which engender an effective nutrient and organic waste removal process. The results of this research indicate that the algae system will remove effectively nutrient and organic waste. In batch cultures, 91.8% dissolved orthophosphate and 83.3% ammonia nitrogen were removed from the sewage in ten days. In continuous flow systems, a detention time of 2.5 days was found adequate to remove 91% T-P, 87% T-N and 95% $NH_3-N$. At 22-28$^{\circ}C$, 60 rpm, with an intensity of 3500 Lux, the specific growth rate, k was 0.59/day in batch experiments. The optimal growth temperature and nutrients rate (N/P) were respectively $25^{\circ}C$ and 3~5. With an abundant supply of untrients, it was possible to sustain substantial population densities in the temperature range of 22~28$^{\circ}C$.

• Applied Biological Chemistry
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• 제29권2호
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• pp.164-174
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• 1986

도열병균에 의한 벼의 목 및 잎도열병에 효과가 좋은 새로운 살균제의 개발을 시도하였다. 농약으로 예상되는 몇몇 3-oxo-1, 2-benzisothiazole-1, 1-dioxide의 새로운 유도체들을 합성하고, 이들 유도체들의 도열병균 (Pyricularia oryzae)에 대한 항균성을 agar medium dilution 방법에 의해 측정하였다. 3-oxo-1, 2-benzisothiazole-1, 1-dioxide의 5 원자 고리의 3개 구조 단위중에서 가장 항균성이 큰 단위는 $R-S-C=N-SO_2-$단위이며, 3개 구조 단위의 항균성 순서는 $RS-C=N-SO_2-\;{\geq}\;RO-C=N-SO_2-\;>\;-CNR-SO_2-$였다. 30개 후보화합물 가운데서 14개의 유도체가 도열병균에 효능이 좋은 것으로 알려진 oryzemate 보다 우수한 항균성을 나타냈다.

• Asian-Australasian Journal of Animal Sciences
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• 제2권4호
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• pp.615-623
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• 1989

Three sheep fitted with rumen cannulae and abomasal cannulae were given daily 750 g (DM) of three diets consisting of straw-manure silage and barley mixture in the ratios of 75:25, 50:50 and 25:75. As the proportion of barley in the diet increased, there was an increase in the amount of OM apparently digested in the rumen and thole tract (P<.01). But ADF digestion was decreased. For the 25:75 diet the $NH_3-N$ content in the rumen showed the highest value, but the total VFA was the lowest. The rumen volume and dilution rate increased with increasing ratio of silage in diets. There were no significant differences between diets in abomasal NAN flow, and the bacterial-N for the 25:75 diet was 7.3 g N as compared with 9.2-9.6 g N for the other diets (P<.01). Rates of bacterial nitrogen synthesis in the rumen were 30.5, 24.1 and 14.9 g N per Kg OM apparently digested in the rumen for the 75:25, 50:50 and 25:75 diets, respectively.

• 반도체디스플레이기술학회지
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• 제11권4호
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• pp.19-23
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• 2012

We report microbolometer characteristic with n-type and p-type amorphous silicon thin film. The n-type and p-type amorphous silicon thin films were made by PECVD. The electrical properties of n-type and p-type a-Si:H thin films were investigated as a function of doping gas flow rate. The doping gas used $B_2H_6/Ar$ (1:9) and $PH_3/Ar$ (1:9). In general, the conductivity of doping a-Si:H thin films increased as doping gas increase but the conductivity of a-Si:H thin films decreased as the doping gas increase because doping gas concentration increase led to dilution gas (Ar) increase as the same time. We fabricated an amorphous silicon microbolometer using surface micromachining technology. The fabricated microbolometer had a negative TCR of 2.3%. The p-type microbolometer had responsivity of $5{\times}10^4V/W$ and high detectivity of $3{\times}10^8cm(Hz)^{1/2}/W$. The p-type microbolometer had more detectivity than n-type for less noise value.