• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.768-774
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• 2009

To improve the productivity of 1,3-propanediol(1,3-PD) with K. pneumoniae DSM4799 using pure glycerol and crude glycerol derived from the biodiesel process, optimizing fermentation conditions was performed by changing environmental factors such as anaerobic/aerobic condition, temperature, glycerol concentration, and pH. When anaerobic conditions were maintained, there was an improved 1,3-PD production compared with that from aerobic/anaerobic 2-stage fermentation. From the results with temperature $26{\sim}37^{\circ}C$, the higher 1,3-PD production yield was observed at $30{\sim}33^{\circ}C$. For an initial glycerol concentration higher than 60 g/L, cell growth and 1,3-PD production were inhibited. When crude glycerol was used, the initial 1,3-PD production appeared to be inhibited. After 48 hr of incubation, however, 1,3-PD production with crude glycerol was even higher than that with pure glycerol, demonstrating the feasibility of 1,3-PD production using crude glycerol as a substrate. Fed-batch fermentation was applied for the high concentration of 1,3-PD without substrate inhibition. By regulating pH at 7 during the fed-batch with glycerol lower than 40 g/L, the yield of 1,3-PD was 25% higher than that without pH regulation(0.56 g/g vs. 0.45 g/g). In conclusion, based on our results, anaerobic conditions, temperature at $30^{\circ}C$, pure or crude glycerol lower than 40 g/L, and pH regulation at 7 were the optimized conditions for 1,3-PD production using K. pneumoniae DSM4799, making it more feasible to produce 1,3-PD at higher concentration and a lower price.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.298-300
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• 2010

화석 연료인 석유, 천연가스, 석탄의 점진적 고갈이 예상됨에 따라 전 세계는 석유와 유사한 성질을 갖는 바이오 오일을 에너지원 및 화학원료로 사용하려는 노력이 증가하고 있다. 바이오 오일 활용분야 중 가장 큰 부분을 차지하고 있는 것은 바이오 디젤로 식물성 오일과 알콜의 전이에스테르화 반응에 의하여 생산되며, 바이오 디젤 1톤당 100kg의 글리세롤이 부산물로 생성된다. 본 연구에서는 바이오 디젤 부산물인 폐글리세롤을 이용하여 다양한 유도체의 생산 및 그 유도체의 가능성에 대하여 살펴보았다.

• The Microorganisms and Industry
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• v.35 no.3
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• pp.10-13
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• 2009

• 건강소식
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• v.26 no.12 s.289
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• pp.34-35
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• 2002

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.209-214
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• 2018

In this paper, the techno-economic analysis of glycerol steam reforming for $H_2$ production capacity of $300m^3\;h^{-1}$ was carried out. The process of glycerol steam reforming was constructed by using Aspen $HYSYS^{(R)}$, a commercial process simulator, and parametric studies for the effect of the operating temperature on $H_2$ production was performed. Moreover, the economic analysis was conducted through an itemized cost estimation, sensitivity analysis (SA) and cash flow diagram (CFD), and the unit $H_2$ production cost was 5.10 $ ${kgH_2}^{-1}$ through the itemized cost estimation of glycerol steam reforming for $H_2$ production capacity of $300m^3\;h^{-1}$. SA was employed to identify key economic factors and various economic indicators such as net present value (NPV), discounted payback period (DPBP), and present value ratio (PVR) were found according to $H_2$ selling price using CFD.

• KSBB Journal
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• v.17 no.6
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• pp.586-589
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• 2002

Lipomyces starkeyi KSM 22 produces dextranase and amylase (DXAMase). The addition of 0.02％ (w/v) 2-deoxy-D-glucose or 0.5% (w/v) glycerol into a 1% (w/v) starch medium increased the final activity of DXAMase produced 2.5 fold or 2.4 fold, respectively, compared to that of a 1% (w/v) starch medium. This activity was similar to that produced with 1% (w/v) dextran. The stability of purified OXAMase at 40$\^{C}$ for 3 weeks was tested using the various enzyme stabilizers. With the addition of 25% (v/v) glycerol, 90.9% of initial activity was left after 3 weeks. For practical use, the addition of 1% (v/v) glycerol with 50 mM of CaCl$_2$ or KH$_2$PO$_4$was adequate and maintained 73.4% of the initial activity under the test conditions used.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.347-351
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• 2013

The preparation of glycerol carbonate (GC) from urea through carbonylation with renewable glycerol was investigated by using ionic liquid catalysts. It was found that quaternary ammonium salt and imidazolium salt ionic liquids with a shorter alkyl chain length and higher nucleophilic anion showed better catalytic performance. The effects of reaction temperature, reaction time and degree of vacuum on the reactivity of TBAC catalyst ware discussed. Zinc chloride ($ZnCl_2$) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the glycerol conversion and GC yield probably due to the acid-base properties of the catalysts.

• Clean Technology
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• v.15 no.1
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• pp.42-46
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• 2009

Solvent-free direct preparation of dichloropropanol (DCP) from glycerol (by-product of bio-diesel production) and hydrochloric acid gas was carried out over acetin catalyst in a gas-liquid batch reactor. For this purpose, acetin mixture and triacetin were used as a homogeneous acetin catalyst. Performance in the acetin-catalyzed reaction was compared to that in the non-catalytic reaction under the same reaction conditions ($110^{\circ}C$, 3 bar, 3 h). Conversion of glycerol in the acetin-catalyzed reactions was ca. 3% higher than that in the non-catalytic reaction, and selectivity for dichloropropanol in the acetin-catalyzed reactions was ca. 50% higher than that in the non-catalytic reaction. It was also revealed that the catalytic performance of triacetin was ca. 2% higher than that of acetic mixture.

• Journal of Embryo Transfer
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• v.11 no.2
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• pp.159-166
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• 1996

본 연구는 돼지 액상정액을 인공수정용 100ml 플라스틱 병에 보존하면서 BF5희석액과 Butschwiler 희석액 간에 보존 온도별 차이를 조사하고, BF5 희석액에서의 글리세롤 농도의 효과를 조사하여 돼지 액상정액을 좀더 장기간 사용할 수 있는 방법을 찾고자 실시하였다. 돼지 액상정액을 5$^{\circ}C$ 냉장고에 보존하면서 조사한 바에 의하면, 37$^{\circ}C$에서 0.5 및 2시간 배양후의 정자운동성은 전체 보존기간동안 BF5 희석액이 Butschwiler 희석액보다 유의하게 (P<0.05) 높게 나타났고, 정상첨체비율은 두 희석액간에 차이가 없었다. 돼지 액상정액을 15$^{\circ}C$에 보존하면서 조사한 바에 의하면, 3일부터 7일 보존시 까지 정자운동성과 정상첨체비율에 있어서 Butschwiler 희석액이 BF5 희석액보다 유의하데 높게 나타났다. BF5 희석액을 이용한 돼지 액상정액의 글리세롤 농도의 효과에 있어서는 최종 글리세롤 농도가 0, 2, 3, 및 5% 보다 1%일 때 가장 높은 정자운동성과 정상첨체비율을 나타내었다. 분만율, 복당 생존자돈수 그리고 출생시 평균 생시체중은 BF5 희석애과 Butschwiler 희석액간에 차이가 없었다. 이상의 연구 결과를 종합해 볼 때 BF5 희석액을 5$^{\circ}C$에서 Butschwiler 희석액은 15$^{\circ}C$에서 6-7일 동안 돼지 액상정액을 보존할 수 있었다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.113-119
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• 2015

The measurement of hydration level in the surface layer of the skin, stratum corneum (SC), gives important information on the biophysical properties and function of the skin barrier such as softness, flexibility, and healthiness of the skin. But it is difficult to measure a consistent hydration level from a sample to another sample due to individual variations and environmental changes. The aim of this study was to evaluate objective hydration after using various products in the SC. The SC Hydration was measured by capacitance (Corneometer$^{(R)}$, C+K, Germany) on the ventral site of forearm from 40 healthy volunteers. The skin surface was chronologically measured immediately after application of the test products and 3 and 6 hours later. We analyzed the averages of five measurements of each site and used the hydration increase rate for correction on untreated site variation. We found that most polyols including glycerol and butylenes glycol influenced directly the hydration increase rate in the SC previously. In this study, glycerol was used to prepare the standard products from 0 to 20 percents and applied to the same volunteers. The individual standard curve showed linear relation to glycerol concentrations. Based on the the standard curve, hydration of SC was converted into hydration increase rate to glycerol concentrations. The converted glycerol concentrations of products were repetitive and reproducible. In addition, the individual standard curve was used to relate the skin type of each individual. These results suggest that the hydration of the SC standardized regardless of external variation and individual skin condition can explain detailed skin state variation. Further studies will be conducted with other ingredients such as surfactants, lipids and aqueous materials, and with other methods for noninvasive measurement.