• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.626-631
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• 2021

One of the nonlinear electrokinetic phenomena around ion exchange membrane is electroconvective instability which can be found in various electrokinetic applications such as electrodialysis, electrochemical battery, microfluidic analysis platform, etc. Such instability acts as a positive transport mechanism for the electrodialysis via amplifying mass transport rate. On the other hands, in the electrochemical battery and the microfluidic applications, the instability provokes unwanted mass transport. In this research, to control the electroconvective instability, the onset of the instability was analyzed as a function of confinement effect as well as applied voltage. As a result, we figured out that the dynamic behavior of electroconvective instability transited as a sequence of stable regime - static regime - chaotic regime depending on the applied voltage and confinement effect. Furthermore, stability curves about the dynamic transition were numerically determined as well. Conclusively, the confinement effect on electroconvective instability can be applied for effective means to control the electrokinetic chaos.

• Membrane Journal
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• v.33 no.4
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• pp.181-190
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• 2023

Wastewater purification is one of the most important techniques for controlling environmental pollution and fulfilling the demand for freshwater supply. Various technologies, such as different types of distillations and reverse osmosis processes, need higher energy input. Capacitive deionization (CDI) is an alternative method in which power consumption is deficient and works on the supercapacitor principle. Research is going on to improve the electrode materials to improve the efficiency of the process. A reverse electrodialysis (RED) is the most commonly used desalination technology and osmotic power generator. Among many studies conducted to enhance the efficiency of RED, MXene, as an ion exchange membrane (IEM) and 2D nanofluidic channels in IEM, is rising as a promising way to improve the physical and electrochemical properties of RED. It is used alone and other polymeric materials are mixed with MXene to enhance the performance of the membrane further. The maximum desalination performances of MXene with preconditioning, Ti₃C₂T_x, Nafion, and hetero-structures were respectively measured, proving the potential of MXene for a promising material in the desalination industry. In terms of osmotic power generating via RED, adopting MXene as asymmetric nanofluidic ion channels in IEM significantly improved the maximum osmotic output power density, most of them surpassing the commercialization benchmark, 5 Wm^-2. By connecting the number of unit cells, the output voltage reaches the point where it can directly power the electronic devices without any intermediate aid. The studies around MXene have significantly increased in recent years, yet there is more to be revealed about the application of MXene in the membrane and osmotic power-generating industry. This review discusses the electrodialysis process based on MXene composite membrane.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.34-34
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• 1992

심혈관계의 중추 조절작용과 고혈압 치료제의 작용기전을 규명하기 위한 연구의 한 단계로서 생체내 미세투석법(in vivo microdialysis)을 이용하여 후 시상하부의 국소부위에서 catecholamine들과 serotonin 및 그 대사체들의 세포와 농도의 변화를 정상혈압 횐쥐 (WKY)에서 관찰하고, 자연발생성 고혈압 횐쥐(SHR)에서 이들의 기준치를 비교하였다. 뇌정위 고정장치에 의해서 미세투석관을 후 시상하부에 위치시킨 후 링거액으로 관류하였다. 모노아민들과 그 대사체들은 고속액체 크로마토그라피와 전기화학 검출기률 이용하여 정량하였다. WKY에서 imipramine(50$\mu$M)의 관류에 의하여 norepinephrine의 농도가 유의하게 증가되었고, 또한 Pargyline (75mg/kg, i.p.)에 의하여 norepinephrine의 농도는 유의하게 증가된 반면에 DOPAC, HVA 및 5-HIAA는 감소하였다. WKY와 SHR에서 비교하였을때 norepinephrine, epinephrine, dopamine, serotonin의 농도는 차이가 없었으나 DOPAC, HVA, 5-HIAA의 농도는 SHR에서 유의하게 증가된 결과를 얻었다. 상의 결과들은 모노아민중에서 norepinephrine이 정상혈압 흰쥐의 후 시상하부에서 유리되는 주된 신경전달물질임을 시사한다. 또한 자연 발생성 고혈압 흰쥐의 후 시상하부에서 dopamine과 serotonin의 교체속도가 증가되었을 가능성이 큰 것으로 사료된다.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.381-383
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• 2002

폴리술폰은 내화학성, 내멸균성, 내가수분해성, 내열성, 강인한 기계적 성질, 내충격성이 우수한 재료로 치수정밀도와 치수안정성이 매우 뛰어난 고분자이다 이런 뛰어난 특성으로 인해 필터 플레이트, 한외여과장치(기체 분리막), 전기ㆍ전자공업분야(전기콘센트소재), 의료용 분야(인공치골, 인공신장기용 박막, 고온에서의 멸균을 필요로 하는 수술용 받침대, 혈액투석용 필터 등) 등 여러 분야에서 이용되고 있다. (중략)

• Membrane Journal
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• v.18 no.2
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• pp.138-145
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• 2008

A series of anion exchange composite membranes were prepared and characterized for electro-dialysis process used in the removal of toxic anion and cation polutants in groundwater or wastewater. The membranes were prepared as follows; first, porous poly(ethylene) (PE) substrates were fully impregnated with monomer mixtures with various ratio of vinylbenzylchloride (VBC), divinylbenzene (DVB) and ${\alpha},\;{\alpha}$-azobis(isobutyronitrile) (AIBN). Second, they were thermally polymerized to yield crosslinked poly(VBC-DVB)/PE composite membranes. Finally, the membranes were treated in trimethylamine (TMA)/acetone to give $-N^+(CH_3)_3$-containing poly(VBC-DVB)/PE membranes. The basic membrane properties such as ion exchange capacity (IEC), electric resistance and water content of the resulting membranes were measured as a function of VBC/DVB and TMA/Acetone content. As a result, the composite membranes showed lower electric resistance, lower water content and higher IEC than commercial anion exchange membranes (AMX, Astom) due to thin PE substrates, indicating that the composite membranes could be successfully applied to the electrodialysis for water treatment.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1191-1195
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• 1997

This study was conducted to investigate the proteolytic properties of saewoojeot (salted and fermented shrimp) on various meat proteins. NaCl content was decreased less than 2% by electrodialysis. As electrodialysis time was passed, the protease activity was increased. The proteolytic activity of crude protease on muscle proteins of beef, pork, chicken was analyzed by SDS-PAGE. Crude enzyme easily degradated both heat-denatured and native meat proteins. Protein degradation was rapidly occurred within 5 min and most all myofibrilar protein was disappeared. Heat-denatured chicken meat (100%) was most easily degraded than heat-denatured pork meat (47%) and beef meat (31%).

• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.226-229
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• 2004

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.71-75
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• 2003

• Proceedings of the Membrane Society of Korea Conference
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• 2000.11a
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• pp.79-82
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• 2000

No Abstract, See Full Text

• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.273-276
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• 2005