• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.153-155
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• 1998

PTFE 합성공정에서 대량으로 사용하는 고가의 음이온계 유화제를 분리/회수하는 것은 경제적인 문제 뿐만 아니라 환경적으로도 매우 중요하다. 음이온계 유화제의 회수에는 Water-evaporation, ion-exchange, freezing, electrodialysis등의 방법을 사용할 수 있다. 그러나 회수에 드는 경비가 높고 장치가 복잡하다는 단점이 잇다. 반\ulcorner에 막분리 공정은 장치가 간단하고 상대적으로 경비가 적게 든다는 장점이 있다. 본 연구에서는 음이온계 유화제를 분리/회수하기 위해서 역삼투 공정을 사용하였다. 그러나 역삼투 공정과 같이 압력을 분리의 구동력으로 하는 막분리 공정에서는 농도분극 및 막오염 현상에 의한 투과량의 감소가 심각하게 일어나며 전체적으로 막분리 공정의 경제성을 떨어뜨리는 주된 요인이 된다. 특히 이온성 막을 사용할 경우 막과 이온성 용질간의 정전기적 포텐셜이 화학적 포텐셜과 함께 투과분리의 구동력을 이루게 되므로 투과거동이 매우 달라지게 된다. 본 연구에서는 막 재료의 이온특성과 음이온성 용질의 농도에 따른 막오염 현상의 관찰 및 이것이 투과거동에 미치는 영향을 관찰하였다. 이를 위해 Sodium alginate, Chitosan, Poly(vinyl alcohol)을 이용하여 각각 음이온성, 양이온성, 중성 막을 제조하여 투과거동을 관찰하였다.

• KSBB Journal
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• v.16 no.1
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• pp.95-98
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• 2001

Various factors affecting the supercritical carbon dioxide extraction of daidzein from soybean were studied. Daidzein was not extracted with pure supercritical carbon dioxide. The ethanol was an efficient modifier for supercritical carbon dioxide to extract daidzein. The extraction efficiency increased as the pressure increased up to 300 bar. At $35^{\circ}C$ and 300 bar, 93% of daidzein was extracted with supercritical carbon dioxide modified with 15% of ethanol.

• Journal of the Korean Vacuum Society
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• v.3 no.1
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• pp.122-129
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• 1994

MWPECVD법으로 CH3CHO-H2 계와 CH4-H2-O2 계로부터 Si 기판 위에 다이아몬드박막을 성장 시키고 성장된 박막을 SEM XRD 및 Raman 분광기로 평가하고 박막과 입자의 성장률을 조사하였다. 마이크로 판전력 950W 반응관압력 80torr 수소유량 200sccm 기판온도 95$0^{\circ}C$ 및 CH3CHO농도 3.5%로 5시간 성장시킨 다이아몬드의 박막성장율은 $4mu$m/hr가 되어고 12%$960^{\circ}C$로 Si기판 위에 5시간 성장시킨 다이아몬드의 박막성장율은 3.2$\mu$m/hr가 되었다.

• The Korean Journal of Rheology
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• v.5 no.1
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• pp.76-84
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• 1993

비상용 고분자 PP/PS 블렌드계에서 상용성을 높이기 위하여 상용화제 SEBS 블록 공중합체를 첨가하였다. 상용화제의 첨가량에 따른 유변학적 그리고 기계적 물성은 상용화 제를 첨가하지 않은 조성보다 물성의 향상을 가져왔다. 형태학적으로 분산상 크기 감소, 분 산분포와 유변학적 성질의 에멀젼 모델을 이용하여 상대적 계면장력을 계산하여 상용화제으 최적 농도를 조사하였다. 또한 상용화제가 더 이상 기계적 물성에 영향을 미치지 않는 농도 를 조사하였다. 형태학적, 유변학적 그리고 기계적 물성조사에 나타난 상용화제의 최적 농도 는 약 1wt%이었다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.126-127
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• 2000

Fe(III) 응집제는 pH 5～9범위에서 Al(III)계 응집제보다 보다 우수한 응집효과를 보였으며 또한 pH의 영향을 거의 받지 않는 것으로 나타났다. 잔류 Fe의 경우 응집제 주입농도와 pH 증가에 영향을 거의 받지 않고 저농도의 잔류 Fe농도를 나타낸 반면, Al(III) 응집제는 잔류 Al의 급격한 증가를 나타내었다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.81-88
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• 2019

In order to understand the effects of the main components of antifoaming agents on the marine benthic ecosystem when silicone-based antifoaming agents are discharged into marine environments, eco-toxicity testing was performed on silicone and alcohol-based antifoaming agent by using benthic amphipod (Monocorophium acherusicum) and luminescent bacteria (Vibrio fischeri). The toxic effects of Polydimethylsiloxane (PDMS) as a main component of silicone-based antifoaming agents on aquatic organisms were also researched. In the results of the eco-toxicity test, luminescent bacteria showed a maximum of 9 times more toxic effects than benthic amphipod for alcohol-based antifoaming agents, and silicone-based antifoaming agents showed a maximum of 400 times more toxic effects than alcohol-based. The $LC_{50}$ and $EC_{50}$ values of PDMS ranged from 10 to $44,500{\mu}g/L$ in phytoplankton, invertebrate, and fish. In the results of applying PBT (P: persistency, B: bioaccumulation, T: toxicity) characteristics as an index showing the qualitative characteristics of PDMS, persistency (P) and bioaccumulation (B) were confirmed. Thus, when PDMS is discharged to marine environments, it could accumulate in the upper trophic level through bioaccumulation and the food chain, which could have negative effects on benthic organisms. The results of this study may be used for objective and scientific risk assessment, considering the major components of antifoaming agents when investigating the effects of various discharged antifoaming agents in marine ecosystem.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.685-691
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• 1993

This study was designed to examine effects of the various levels of sardine and safflower oil mix on lipid contents of serveral tissues in dietary hyperlipidemic rats. Experimental oils were 16% butter(control group), 8% butter +8% olive oil(group 2) 8% butter+8% sardine oil(group 3) 8% butter+6% sardine oil+2% safflower oil(group 4), 8% butter+4% sardine oil+4% safflower oil(group 5),8% butter+2% sardine oil+6% safflower oil(group 6) and 8% butter+8% safflower oil(group 7). The diet administered to the male rats of Sprague-Dawley were fed for 4 weeks. In livers, total cholesterol and triglyceride, phospholipid concentrations were lowest in the group 5 and free cholesterol concentrations were lower in the groups 4 and 5, particularly. Total cholesterol and triglyceride concentrations in brain were significantly lower in the group 5 and phospholipids were lowest in the group 3, while free cholesterol were group 7. In testes, total cholesterol and triglyceride, phospholipid, free cholesterol concentrations were lower in the all experimental groups than the control group, but those of kidney were lower in the groups 3, 7 than in the control group. Feeding mixed oil having equal quantity of sardine oil and safflower oil were effective on the reduction of the lipid contents in the principal tissues. It might be due to the effects of appropriate ratios of P/S, 0.85 and n-6/n3-p, 2.85 in the test lipids.

• Proceedings of the Korean Society of Radiological Science
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• 1995.05a
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• pp.140-141
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• 1995

• The KSFM Journal of Fluid Machinery
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• v.9 no.3 s.36
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• pp.58-63
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• 2006

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.337-345
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• 2010

The current study was conducted to estimate the effect of dietary taurine on performance, egg quality, blood parameter, liver lipids and lipid peroxidation level of laying hens fed high fat diet. Two hundred eighty laying hens, forty five weeks of age, were allocated to four treatment groups with seven replicates of 10 each per treatment for 4 weeks. Experimental diets were assigned to each of the four groups: control diet (CON), CON with 0.5% taurine (CT), CON with 5% soybean oil (HF), and CON with 5% soybean oil and 0.5% taurine (HFT). Egg weight was significantly lower in the control than the CT (P<0.05). However, the HFT was similar to the level compared to both control and HF. Serum concentrations of total cholesterol, triglyceride and glutamic oxaloacetic transaminase (GOT) were significantly decreased by about 30%, 36% and 20%, respectively in the HFT compared to the HF (P<0.05). In the liver tissue, triglyceride concentration tended to be lower by about 28% in the HFT compared to the HF (P<0.05). The hepatic lipid peroxidation level was significantly decreased by about 25% in the HFT compared to the HF (P<0.05). These results indicated that taurine supplementation improved the serum total cholesterol, triglyceride concentration, and decreased hepatic lipid peroxidation level without affecting performance in laying hens fed high fat diet.