• 한국수소및신에너지학회논문집
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• 제7권2호
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• pp.129-135
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• 1996

전해질로써 $Nafion^{(R)}$과 같은 고체고분자막과 수소/산소 가스가 계면을 형성할 경우의 전압전류특성을 측정하였다. 사용된 가스는 수소와 산소의 조성비를 달리하여 혼합한후 공급하였다. 사용된 전극은 상업용 탄소 기체 확산 전극을 이용하였으며 전극의 분산된 촉매와 전해질과의 접촉을 용이하게 하기위해 5% $Nafion^{(R)}$을 발라주었다. 직류전원 공급장치를 이용하여 산화 전극과 환원 전극에 걸어주는 전압을 조정하였다. 전압전류의 분석결과로부터 에너지효율은 수소/산소혼합물의 수소농도에 예민하게 의존함을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제31권3호
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• pp.447-455
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• 2021

Strains of four Bacillus spp. were respectively inoculated into sterilized soybeans and the free amino acid profiles of the resulting cultures were analyzed to discern their metabolic traits. After 30 days of culture, B. licheniformis showed the highest production of serine, threonine, and glutamic acid; B. subtilis exhibited the highest production of alanine, asparagine, glycine, leucine, proline, tryptophan, and lysine. B. velezensis increased the γ-aminobutyric acid (GABA) concentration to >200% of that in the control samples. B. sonorensis produced a somewhat similar amino acid profile with B. licheniformis. Comparative genomic analysis of the four Bacillus strains and the genetic profiles of the produced free amino acids revealed that genes involved in glutamate and arginine metabolism were not common to the four strains. The genes gadA/B (encoding a glutamate decarboxylase), rocE (amino acid permease), and puuD (γ-glutamyl-γ-aminobutyrate hydrolase) determined GABA production, and their presence was species-specific. Taken together, B. licheniformis and B. velezensis were respectively shown to have high potential to increase concentrations of glutamic acid and GABA, while B. subtilis has the ability to increase essential amino acid concentrations in fermented soybean foods.

• Advances in concrete construction
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• 제15권4호
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• pp.241-249
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• 2023

The unsteady mixed convection Casson type MHD nanofluid flow in the stagnation point with motile microorganism around a spinning sphere is investigated. Time dependent flow dynamics is considered. Similarity transformations have been employed to transfer the governing partial differential structure into ordinary differential structure. The impact of distinct parameters is examined via tables and graphs. The impact of rotational parameter (spin) on profiles of velocity profiles, temperature and concentration is revealed for unsteady mixed convection Casson type MHD nanofluid flow. It is observed that it is clear that rotational parameter has a great effect on non-dimensional primary velocity component but rotational parameter has a slight impact on non-dimensional secondary velocity component. The validity of the current investigation is authorized through comparing the existing outcomes with previous published literature.

• Nutritional Sciences
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• 제9권2호
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• pp.74-81
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• 2006

The present study examined the effect of soy isoflavones on lipid metabolism in growing female rats. Rats were randomly assigned to three different groups and provided experimental diets for 9 weeks. The experimental groups were classified into 1) a control group, 2) a soy protein isolate group: soy (+)) group and 3) a soy protein concentration group: soy (-)) group. Diets contained either casein or one of two soy proteins with (soy (+)) or without isoflavones (soy (-)). Serum triglyceride concentration showed no significant differences among the experimental groups. Serum total cholesterol concentration was significantly lower in both the soy (+) and soy (-) groups than in the control group and LDL-cholesterol concentration was significantly lower in the soy (+). Serum HDL-cholesterol concentration was significantly higher in the control group than in the soy protein groups but the HDL-cholesterol share rate in total cholesterol tended to be lower in the control group than in the soy protein groups, insignificant as it was. Hepatic IDL receptor mRNA level was significantly increased in the soy (+) group when compared to the other two groups to be 20% higher than the control group. In conclusion, soy protein isolate, soy protein rich with isoflavones reduced serum total cholesterol and LDL-cholesterol concentration and increased hepatic IDL receptor mRNA expression in growing female rats. Therefore, it is considered that the intake of soy isoflvones during puberty can be advantageous in terms of the long-tenn control of serum lipid.

• Food Science and Biotechnology
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• 제17권2호
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• pp.287-294
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• 2008

Protective effects of cheonggukjang fermented with 20% red ginseng (RC) were observed in streptozotocin (STZ)-induced diabetic rats by measuring levels of blood glucose, serum lipid profiles, and hepatic reactive oxygen species generating and scavenging enzymc activities. RC diet was prepared by mixing with AIN-76 diet at the final concentration 2%, and it was fed to STZ-induced diabetic rats for 3 weeks. The RC dict was significantly improved body weight, feed efficiency ratio, levels of serum glucose, and serum and hepatic lipids in diabetes. The significantly elevated O type activity of xanthine oxidase in diabetes was also greatly decreased by the RC diet. The treatment of RC showed the improved hepatic glutathione s-transferase activities in the diabetic animals. The present study indicates that cheonggukjang fermented with red ginseng could ameliorate STZ-induccd diabetic symptoms such as aggravated blood glucose levels, serum lipid profiles, and even the conditions of oxidative stress.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.223-229
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• 1999

The two optimal control algorithms, singular approximation and minimum principle, were compared in this paper. The switching time with singular approximation was determined with mathematical derivation and the optimal control profile of specific growth rate was also calculated with minimum principle. The optimal control profiles were calculated by making simple model correlating the specific cell growth rate and specific product formation rate. The optimal control profiles calculated by singular approximation approach were similar to stepwise form of those calculatd by minimum principles. With the minimum principle, the product concentration was 8% more than that of singular approximation. This performance difference was due to a linearization of a nonlinear function with singular approximation. This optimal approaches were applicable to any system with different optimal cell growth and product formation.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.35-38
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• 1998

The momentum, heat and mass transport in the melt of several sizes of crucibles are calculated using a three dimensional numerical simulation technique with and without the k-$\varepsilon$ turbulent model. When turbulent model is not used, non-axisymmetric profiles of velocity, temperature and oxygen concentration appear in the melt of all sizes of crucibles. Axisymmetric profiles are obtained when the k-$\varepsilon$ model is adopted.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2004년도 추계학술대회 논문집
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• pp.90-93
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• 2004

Micro PIV was applied to measure velocity profiles of two-fluid flows in a microchannel. In this work, the two-fluid flow of two glycerol-water mixtures was measured for three cases $(\phi=0\;and\;\phi=0.2;\;\phi=0.1\;and\;\phi=0.5;\;\phi=0\;and\;\phi=0.6)$. The flow rates of two fluids were the same. The experimental velocity profiles agreed well with numerical simulations. However, a slight deviation was found in the fluid with low concentration. Rather than the effects of the varying refractive indices inside the channel, the high velocity gradient effect was thought as the main source of the deviation.

• 한국수산과학회지
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• 제43권6호
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• pp.637-641
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• 2010

The antibiotics-resistance profiles of 28 strains of Vibrio parahaemolyticus isolated from seawater were investigated. All of the strains studied were resistant to ampicillin (100%), but susceptible to 12 other antibiotics. The minimum inhibitory concentration (MIC) of V. parahaemolyticus to ampicillin was as high as $1,024-2,048\;{\mu}g{\cdot}mL^{-1}$. The phenotype of strain 8 changed from ampicillin-resistant to susceptible with an in-frame deletion mutant of VPA0477, a putative ${\beta}$-lactamase gene, and the MIC for ampicillin of the mutant strain was $1{\mu}g{\cdot}mL^{-1}$. In conclusion, our findings suggest that the VPA0477 gene acts as a ${\beta}$-lactamase in ampicillin-resistant V. parahaemolyticus strains.

• 자원환경지질
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• 제29권1호
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• pp.77-85
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• 1996

The vertical concentration profiles of chromium in sediment cores were measured from Lakes Superior, Michigan, and Ontario in an attempt to determine spatial and historical variations. Pre-industrial concentrations of chromium are typical for soils in the Great Lakes region. Only Lakes Ontario and Michigan exhibit anthropogenic enrichments of chromium in the sediments. Sediment profiles in Lakes Ontario and Michigan indicate that the rates of anthropogenic chromium loading to the Great Lakes region are decreasing. Focusing corrected inventories are similar within each lake and those are higher in Lake Ontario than Lake Michigan. The results are interpreted to indicate that there is a small atmospheric component to chromium inputs to the Great Lakes and that the relative importance of this input decreases from Lake Superior to Lake Ontario.