• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.903-904
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• 2006

In recent years, the research in porous metal got rapid development in China, especial in Northwest Institute for Non-ferrous Metal Research (NIN). Many porous metals with different raw material and different shapes were developed, which successfully employed in many fields. We believe we will earn more rapid development in the future.

• Membrane Journal
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• v.27 no.2
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• pp.199-204
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• 2017

In this study, a study was carried out for the separation of metal ions in lignin extract discharged from the pulp process. alumina powders were mixed with DMAc (N, N-dimethylacetamide) solvent and PESf (Polyethersulfone) polymer, PVP (polyvinylpyrrolidone) dispersant was added and slip casting method was used to prepare the membrane. The membrane was measured for pore size through a CFP (Capillary Flow Porometer) device and the surface and cross-section of the membrane were observed through a FE-SEM (Field Emission Scanning Electron Microscope). The flux was calculated by measuring the filtered weight per hour using a separation experiment device. Pore size measurements were performed under increasing pressure from 0 psi to 30 psi. The pore size of the membrane was $0.4{\mu}m$ and the flux decreased from the initial flux value of $6.36kg{\cdot}m^{-2}{\cdot}h^{-1}$ to $1.98kg{\cdot}m^{-2}{\cdot}h^{-1}$ due to the fouling of the membrane. After the permeation experiment, membrane contaminants were removed by simple washing. Separation experiments showed that Na contained in the initial lignin extract was reduced by 69%, Fe was removed by 87%, K by 95%, Ca by 93% and Mg by 96%.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.462-465
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• 2002

물에 용해되어 있는 금속이온의 분리를 위한 선택성이 있는 분리 막의 개발은 환경오염이 날로 심각해지고 있는 오늘날에 환경오염의 개선, 에너지절약, 자원의 재활용 등 문제를 해결함에 있어서 아주 중요한 작용을 하게 될 것이다. 물에 용해되어 있는 금속이온을 선택적으로 분리하기 위해 일반적으로 캐리어(carrier)를 함유한 Carrier-Facilitated Transport Membrane (CFM)을 이용하게 되는데, 이 방면에 대한 연구는 주로 유기 상에 용해되어 있는 캐리어를 microporous한 필름에 지지하게 하는 방식으로 만들어진 Supported Liquid Membrane (SLM) 혹은 Elusion Liquid Membrance (ELM)의 개발에 대한 팽대한 연구가 이루어 졌다(1). (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 2002.05a
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• pp.106-109
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• 2002

No Abstract, See Full-text

• Toxicological Research
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• v.23 no.1
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• pp.1-9
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• 2007

Transporters are membrane proteins that mediate the transfer of substrate across the cellular membrane. In this overview, the characteristics and the toxicological relevance were discussed for various types of transporters. For drug transporters, the overview focused on ATP-binding cassette transporters and solute carrier family 21A/22A member transporters. Except for OCTN transporters and OATP transporters, drug transporters tend to have broad substrate specificity, suggesting drug-drug interaction at the level of transport processes (e.g., interaction between methotrexate and non-steroidal anti-inflammatory agents) is likely. For metal transporters, transporters for zinc, copper and multiple metals were discussed in this overview. These metal transporters have comparatively narrow substrate specificity, except for multiple metal transporters, suggesting that inter-substrate interaction at the level of transport is less likely. In contrast, the expressions of the transporters are often regulated by their substrates, suggesting cellular adaptation mechanism exists for these transporters. The drug-drug interactions in drug transporters and the cellular adaptation mechanisms for metal transporters are likely to lead to alterations in pharmacokinetics and cellular metal homeostasis, which may be linked to the development of toxicity. Therefore, the transporter-mediated alterations may have toxicological relevance.

• The Korean Journal of Zoology
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• v.30 no.4
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• pp.410-416
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• 1987

The effect of heavy metal ions on the synthesis of proteins in cultured chick embryonic muscle cells were examined by labeling the cellular proteins with 35S-methionine and the surface proteins with Nalssl and lactoperokidase. The protein pattern in the cells cultured for 48 hrs showed little or no difference whether or not the cells were treated with any of the metal ions including Cu2+, Cd2+ and Hg2+, which are known to block the fusion of mypblasts. However, a 43kd protein disappeared from the control cells cultured for 72 hrs but remained unchanged in the cells treated with the metal ions. When analyzed for the syntheiic pattern of membrane proteins, addition of the ions (particularly of Cda+ and Cr3+) caused a marked increase in the level of 66kd protein, as compared to that in the untreated cells. By contrast, the level of 29kd protein was much higher in the control cells than in the cells treated with the metal ions. These results suggest that the heavy metal ions appear to block the degradation of 43kd soluble protein and 66kd membrane protein, perhaps by inhibiting a metalloprotease, which may be essential for the myogenic process of embryonic muscle cells.

• Membrane Journal
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• v.12 no.1
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• pp.51-53
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• 2002

The hydrogen ions in poly (vinyl alcohol) (PVA)/sulfosuccinic acid (SSA) membranes substiuted with $Li^+, Na^+, and K^+/ $of monvoalent metal ions, $Mg^{2+}, Ca^{2+} and Ba^{2+}$ of divalent metal ions, and $Al^{3+}$ of trivalent metal ion. In addition, $Li^+ ions were exchanged with varing reaction time. The effects of metal ions exchanged were investigated in terms of methanol permeability -uling diffusion cell. The methanol permeabilies decreased in the sequence of $Na^+, Li^+ and K^+$ and this might be due to the 'Salting-out' effect while the methanol permeabilities for divalent and trivalent ion-substituted membranes were affected by the combined effects of salting-out, eletrostatic crosslinking and extent of metal ion substiution. As for $Li^+$ ions, methanol permeabilities of PVA/SSA membranes decreased in proportion to the degrees of subsituted $Li^+$ ions.

• Journal of the Korean Electrochemical Society
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• v.23 no.4
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• pp.90-96
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• 2020

Polymer electrolyte membrane fuel cells, which convert the chemical reaction energy of hydrogen into electric power directly, are a type of eco-friendly power for future vehicles. Due to the sluggish oxygen reduction reaction and costly Pt catalyst in the cathode, the research related to the replacement of Pt-based catalysts has been vitally carried out. In this case, however, the performance is significantly different from each other and a variety of factors have existed. In this review paper, we rearrange and summarize relevant papers published within 5 years approximately. The selection of precursors, synthesis method, and co-catalyst are represented as a core factor, while the necessity of research for the further enhancement of activity may be raised. It can be anticipated to contribute to the replacement of precious metal catalysts in the various fields of study. The final objective of the future research is depicted in detail.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.122-127
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• 2006

The aim of this study was to investigate the characteristics of membrane fouling caused by soluble organic materials in a membrane bioreactor process. For the removal of filterable organic materials (FOC) smaller than $1{\mu}m$, coagulants and activated carbon were added. A membrane bioreactor using a submerged $17{\mu}m$ metal sieve was operated in laboratory scale to examine the possibility of membrane fouling control. As the dosage of GAC and coagulant increased, the residual FOC concentration decreased and the permeate flow rate increased markedly. The permeate flux increased with an increased PACl addition at the range from 0 to 50 mg/l. At coagulant dosage of 27mg/l, the removal of FOC was about 46% and the flux increased to 3.5 times compared to the case without PACl addition. The permeate flux increased gradually with an increase in GAC dosage. At GAC dosage of 50mg/L, the permeate flux was about 2 times higher compared that for raw water. The particle in the range of $0.1{\sim}1.0{\mu}m$ were removed effectively by the addition of GAC and coagulant. Higher osage of GAC and coagulant, led to higher removal of FOC. A different set of experiments was also performed to investigate the effect of pretreatment on the permeation ability of MBR system using the metal sieve membrane. After 40 hours of operation, the permeate flux was about 1,000 ($L/m^2-hr$), which is 20 times higher compared to the results in literature. It is likely that combined pretreatment using coagulant and activated carbon was the most effective to resolve membrane fouling problems. Moreover, the continuous operations could be successful by applying this pretreatment method.

• Membrane Journal
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• v.21 no.2
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• pp.148-154
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• 2011

Metal-ceramic composite membrane have been developed to separate hydrogen from mixed gases, particularly product streams generated during coal gasification and methane reforming. Cermet membrane was fabricated with palladium as hydrogen-permeable metal and $Y_2O_3$-stabilized $ZrO_2$ (YSZ) as ceramic supporter. As-prepared membrane showed dense structure with continuous channel of palladium. The hydrogen flux of Pd/YSZ membrane have been measured in the range of 0.5~2 atm with 100% hydrogen gas. The results indicate that the hydrogen flux was 0.333 mL/$min{\cdot}cm^2$ at $450^{\circ}C$ and 2 atm. The crack was formed in the surface and cross-section of membrane.