• 한국수소및신에너지학회논문집
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• 제24권4호
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• pp.334-339
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• 2013

In this study, as a candidate of the carbon dioxide ($CO_2$) absorbents, the mixture solution of polyethylene glycol dimethyl ether (PEGDME) and tetrahydrofuran (THF) were investigated. $CO_2$ absorption rate was measured by using high pressure $CO_2$ screening equipment in the range of 1 - 10wt% THF. Absorption capacity of the mixture solution was also estimated. Based on the results, we found that mixture solution containing THF had higher absorption rate and $CO_2$ loading capacity compared to PEGDME at $25^{\circ}C$.

• 폴리머
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• 제24권6호
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• pp.763-769
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• 2000

E-beam 전조사법을 이용하여 아크릴산과 스틸렌 단량체를 폴리프로필렌 섬유에 그라프트 반응시켜 PP-g-(AAc/Sty) 공중합체를 합성하고 술폰화 반응시켜 다관능성 섬유상 양이온 교환체를 합성하였다. 합성체의 그라프트율은 물과 메탄올 혼합비가 30 : 70 vol%인 혼합용매에서 아크릴산과 스틸렌, 단량체비가 30 : 70 vol%일 때 190%로 최대이었으며 혼합용매의 조성비가 일정할 때 아크릴산 단량체의 양이 증가할수록 그라프트율은 감소하였다. 또한 이온교환체의 이온교환용량은 4.6 meq/g이었으며, 술폰화 이온교환체와 아크릴산 이온교환체의 리튬이온에 대한 흡착량을 비교한 결과 본 연구에서 합성한 이온교환체의 흡착성이 우수한 것으로 나타났다.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2004년도 Proceedings of 2004 Korea-Japan Joint Seminar on Particle Image Velocimetry
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• pp.65-74
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• 2004

Measurement of concentration distributions of suspended particles in a micro-channel is out of the most crucial necessities in the area of Lab-on-a-chip to be used for various bio-chemical applications. One most feasible way to measure the concentration field in the micro-channel is using micro-LIF(Laser Induced Fluorescence) method. However, an accurate concentration field at a given cross plane in a micro-channel has not been successfully achieved so far due to various limitations in the light illumination and fluorescence signal detection. The present study demonstrates a novel method to provide an ultra thin laser sheet beam having five(5) microns thickness by use of a micro focus laser line generator. The laser sheet beam illuminates an exact plane of concentration measurement field to increase the signal to noise ratio and considerably reduce the depth uncertainty. Nile Blue A was used as fluorescent dye for the present LIF measurement. The enhancement of the fluorescent intensity signals was performed by a solvent mixture of water $(95\%)$ and ethanol (EtOH)/methanol (MeOH) $(5\%)$ mixture. To reduce the rms errors resulted from the CCD electronic noise and other sources, an expansion of grid size was attempted from $1\times1\;to\;3\times3\;or\;5\times5$ pixel data windows and the pertinent signal-to-noise level has been noticeably increased accordingly.

• 한국세라믹학회지
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• 제51권4호
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• pp.324-331
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• 2014

The dispersion characteristics of AlN-4.5 wt% $Y_2O_3$ powder mixture by various dispersants were investigated in ethanol and methyethly-ketone (MEK) solvents. In general, the cationic polymer dispersants demonstrated superior dispersion of the powder as compared to the non-ionic ester-type dispersants or anionic phosphate-ester-based ones. The dispersion performance of the cationic polymer dispersants was sensitive to the type of solvent. An anhydric maleic-acid-based graft copolymer dispersant, AFB-1521, demonstrated a very good dispersion capability in ethanol but exhibited a much inferior dispersion in MEK. On the other hand, the dispersion of the powder mixture was very good with a phosphate-ester-based block polymer dispersant, BYK-111, in MEK solvent, while dispersionwas much degraded in ethanol.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.93-94
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• 1999

• 자원리싸이클링
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• 제9권4호
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• pp.28-36
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• 2000

본 연구는 입자가 혼합된 용제를 이중판형 열교환기 내에서 가열 및 증발과정을 통해 건조이자와 용제로 분리하여 회수하기 위한 연속식 순간 진공건조 시스템 해석에관한 것이다. 진공건조시스템은 용제 공급펌프, 이중관형 열교환기, 진공 스프레이 챔버 및 응축기로 구성된다. 연속적으로 공급되는 용제는 이중관형 열교환기 내에서 가열, 팽창 및 증발되며 관 출구부에서 팽창된 증기가 진공 스프레이 챔버 내로 분사되고 증기는 응축기로 수송되어 용제로 회수되고 입자는 관성력에 의해 증기로부터 분리되어 건조된다ㅣ. 안료입자가 함유된 벤젠 및 알킬벤젠의 분리 및 회수성능 실험을 수행한 결과, 습분양 1.1%로 건조된 안료입자를 94% 회수하였고, 99.9 wt%의 고순도 벤젠을 88% 회수하였다. 평균직경이 $6.5\mu\textrm{m}$인 안료입자를 진공건조시스템의 이중관형 열교환기에서 관출구부의 고속 분사에 의한 폭발적 분산력에 의해 입경이 14%감소된 $5.6\mu\textrm{m}$ 크기의 건조 안료입자를 회수하였다. 따라서 진공건조시스템은 용제에 함유된 입자를 건조 및 분리하여 미분제 제품으로 히수하는데 효율적이며 폐용제 정제용으로 적용이 가능하다.

• 한국식품과학회지
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• 제15권1호
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• pp.70-76
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• 1983

과당과 포도당의 혼합물로부터 과당의 분리에 관한 염과 용매의 영향을 이들 두 당의 용해도 차를 이용한 결정화 방법에 의해서 조사하였다. 결정화 방법은 이들 두 당의 혼합용액에 알콜과 $CaCl_2$, NaCl을 첨가하여 실행하였다. 에틸알콜이 메틸알콜, iso-프로판올 및 n-부탄올보다 분리에 더 좋은 용매라는 것을 알았으며, 알콜용액에 NaCl을 첨가하면 $CaCl_2$를 첨가하는 경우와 소금을 첨가하지 않은 경우보다 더 낳은 결과를 가져온다는 것을 알았다. 이 경우에 있어서 분리하려는 feed 용액에서의 과당과 포도당의 비율이 1 : 1 이었는데 feed 용액에서의 두 당의 조성비를 변화시킨 결과 더 좋지 않은 분리 결과를 가져왔다. 결론적으로 과당의 가장 좋은 분리는 20% 물과 40% 과당, 40% 포도당으로 이루어진 feed 용액에 NaCl과 에틸알콜을 첨가함으로써 결정화시키려는 용액에서의 각 성분이 에틸알콜 36ml, 물 4ml, 과당 8gm, 포도당 8gm, NaCl 0.25gm과 같은 조성을 이룰 때 얻어졌다.

• 자원리싸이클링
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• 제22권6호
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• pp.19-25
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• 2013

염산용액에서 지르코늄과 하프늄을 분리하기 위해 LIX63과 Cyanex301을 단독 또는 혼합하여 용매추출실험을 수행했다. 상기 추출제를 단독으로 사용하는 경우 염산용액의 pH 1에서 4사이의 범위에서 두 금속은 양이온 추출반응에 의해 추출되었으며, 추출율이 비슷하여 분리가 어렵다. LIX63과 TBP, Cyanex301과 TBP의 혼합용매를 사용하는 경우 본 실험범위에서 역상승효과가 나타났다. Cyanex301과 TBP의 혼합용매의 경우에 염산농도가 증가함에 따라 지르코늄보다 하프늄의 추출율이 급격히 감소하여 분리가능성이 존재하였다. 한편 Cyanex301과 LIX63의 혼합용매의 경우 두 금속의 분리에 효과가 없었다.

• Journal of Pharmaceutical Investigation
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• 제20권4호
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• pp.193-198
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• 1990

To increase the dissolution rate of furosemide, cogrinding or coprecipitating of furosemide with povidone was carried out. The ground mixture of furosemide with povidone was prepared by cogrinding in a ceramic ball mill and the coprecipitate was prepared by solvent method using methanol. The povidone ground mixture and the coprecipitate showed a faster and more enhanced dissolution rate than the physical mixture or intact furosemide. The IR, DTA and TGA studies showed the physicochemical modifications of furosemide from the ground mixture and the coprecipitate. An interaction, in the ground mixture and in the coprecipitate, such as association between the functional groups of furosemide and povidone might occur in the molecular level. The coprecipitating and cogrinding techniques with povidone provided a promising way to increase the dissolution rate of poorly soluble drugs.

• 한국도로학회논문집
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• 제18권6호
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• pp.97-104
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• 2016

OBJECTIVES : The objective of this research is to develop additives for the modification of Solvent DeAsphalting Residue (SDAR) to be used as pavement materials, and evaluate the performance of asphalt mixture manufactured using the SDAR modified by developed additives. METHODS : The SDAR generally consists of more asphaltenes and less oil components compared to the conventional asphalt binder, and hence, the chemical/physical properties of SDAR are different from that of conventional asphalt binder. In this research, the additives are developed using the low molecular oil-based plasticizer to improve the properties of SDAR. First, the chemical property of two SDARs is analyzed using SARA (saturate, aromatic, resin, and asphaltene) method. The physical/rheological properties of SDARs and SDARs containing additives are also evaluated based on PG-grade method and dynamic shear-modulus master curve. Second, various laboratory tests are conducted for the asphalt mixture manufactured using the SDAR modified with additives. The laboratory tests conducted in this study include the mix design, compactibility analysis, indirect tensile test for moisture susceptibility, dynamic modulus test for rheological property, wheel-tracking test for rutting performance, and direct tension fatigue test for cracking performance. RESULTS : The PG-grade of SDARs is higher than PG 76 in high temperature grades and immeasurable in low temperature grades. The dynamic shear modulus of SDARs is much higher than that of conventional asphalt, but the modified SDARs with additives show similar modulus compared to that of conventional asphalt. The moisture susceptibility of asphalt mixture with modified SDARs is good if, the anti-stripping agent is included. The performance (dynamic modulus, rutting resistance, and fatigue resistance) of asphalt mixture with modified SDARs is comparable to that of conventional asphalt mixture when appropriate amount of additives is added. CONCLUSIONS : The saturate component of SDARs is much less than that of conventional asphalt, and hence, it is too hard and brittle to be used as pavement materials. However, the modified SDARs with developed additives show comparable or better rheological/physical properties compared to that of conventional asphalt depending on the type of SDAR and the amount of additives used.