• 제목/요약/키워드: membrane processes

Search Result 775, Processing Time 0.032 seconds

Determination of relevant Characteristics for Cartridge Filters

  • Ogawa, Takao
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1993.04a
    • /
    • pp.1-11
    • /
    • 1993
  • Cartridge filters are widely used in liquid-solid separation processes. To select a proper filter system for the requirements of a given application, a knowledge of filter efficiency and dirt capacity is required. The filter manufacturer needs to provide data which are based on test procedures simulating real parameters on a laboratory scale. There does not exist at present a standard for liquid filter testing (with the exception of the Multipass Test to ISO4752 for hydraulic filters). Users have to work with data based on different test procedures. This paper will discuss principles of filter testing, efficiency andd dirt capacity results as a function of test parameters, and data interpretion to provide a guideline for the end user.

  • PDF

NTAㆍNi2+-Functionalized Quantum Dots for VAMP2 Labeling in Live Cells

  • Yu, Mi-Kyung;Lee, Su-Ho;Chang, Sung-Hoe;Jon, Sang-Yong
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.6
    • /
    • pp.1474-1478
    • /
    • 2010
  • An efficient method for labeling individual proteins in live cells is required for investigations into biological mechanisms and cellular processes. Here we describe the preparation of small quantum dots (QDs) that target membrane surface proteins bearing a hexahistidine-tag ($His_6$-tag) via specific binding to an nitrilotriacetic acid complex of nickel(II) ($NTA{\cdot}Ni^{2+}$) on the QD surfaces. We showed that the $NTA{\cdot}Ni^{2+}$-QDs bound to His-tag functionalized beads as a cellular mimic with high specificity and that QDs successfully targeted $His_6$-tagged vesicle-associated membrane proteins (VMAP) on cell surfaces. This strategy provides an efficient approach to monitoring synaptic protein dynamics in spatially restricted and confined biological environments.

Effect of Amino Acids in Silver Polymer Electrolyte Membranes on Facilitated Olefin Transport

  • Kang, Sang-Wook;Kim, Jong-Hak;Jongok Won;Kookheon Char;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2004.05a
    • /
    • pp.78-81
    • /
    • 2004
  • Here the effect of various amino acids on the separation performance for these two contrastive membranes is investigated. It was especially focused on the structures of amino acids, and their effects on the silver ion activity as well as the interaction between polymer electrolytes and amino acid. The amino acids studied include asparagine, valine, glutamic acid and lysine.(omitted)

  • PDF

The Structural Transitions of $\pi$-Complexes of Poly(styrene-b-butadiene-b-styrene) Block Copolymers with Silver Salts and Their Relation to Facilitated Olefin Transport

  • Lee, Dong-Hoon;Kim, Jong-Hak;Jongok Won;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2004.05a
    • /
    • pp.211-215
    • /
    • 2004
  • Olefins are the most important feedstock in the petrochemical industry and thus the separation of olefin/paraffin mixtures is crucial to that industry. At present, this separation is mostly carried out using cryogenic distillation processes that require enormous capital investment and have high operational costs.(omitted)

  • PDF

Development of a MEMS Structure for an Infrared Focal Plane Array (Infrared Focal Plane Array 용 MEMS 구조체 개발)

  • Cho, Seong-M.;Yang, Woo-Seok;Ryu, Ho-Jun;Cheon, Sang-Hoon;Yu, Byoung-Gon;Choi, Chang-Auck
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.8
    • /
    • pp.1461-1465
    • /
    • 2007
  • A micromachined sensor part for an infrared focal plane array has been designed and fabricated. Amorphous silicon was adapted as a sensing material, and silicon nitride was used as a membrane material. To get a good efficiency of infrared absorption, the sensor was made as a ${\lambda}/4$ cavity structure. All the processes were done in $0.5\;{\mu}m$ iMEMS fab. in the Electronics and Telecommunication Research Institute (ETRI). The processed MEMS sensor structure had a small membrane deflection less than $0.3\;{\mu}m$. This excellent deflection property can be attributed to the rigorous balancing of the stresses of individual layers. The efficiency of infrared absorption was more than 75% in the wavelength range $8\;-\;14\;{\mu}m$.

The comparative study of different membranes for electrolytic cell for the hydrogen peroxide generation (과산화수소 발생을 위한 전해셀용 양성자 교환 막의 비교)

  • You, Sun-Kyung;Kim, Han-Joo;Park, Soo-Gil
    • Proceedings of the KIEE Conference
    • /
    • 2007.07a
    • /
    • pp.1361-1362
    • /
    • 2007
  • There is great interest in the applicability of electrogenerated hydrogen peroxide to a wide variety of industrial processes, usually involving oxidation of organics. Hydrogen peroxide is now employed for the bleaching of mechanical pulp and the bleaching of chemical pulp in the pulp and paper industry, thus displacing the traditional alkaline treatments with chlorine-based chemicals. This psper reperts a comparative study of $H_{2}O_{2}$ electogeneration on gas-diffusion electrode in divided cell with several $Nafion^{(R)}$ protonexchange membranes, Russian cation-exchange membrane MK-40 and SPEEK membrane. The influence of different PEMs on electrochemical cell voltage, current efficiency and energy consumption of hydrogen peroxide electrogeneration has been stadied.

  • PDF

Phospholipases Dl and D2 Regulate Different Phases of Exocytosis in Mast Cells

  • Lee, Jun-Ho;Chang, Sung-Ho;Kim, Young-Mi;Her, Her Erk;Choi, Wahn-Soo
    • Proceedings of the PSK Conference
    • /
    • 2003.10b
    • /
    • pp.135.1-135.1
    • /
    • 2003
  • The rat mast cell line RBL-2H3 contains both phospholipase D (PLD)1 and PLD2. Previous studies with this cell line indicated that expressed PLD1 and PLD2 are both strongly activated by stimulants of secretion. We now show by use of PLDs tagged with enhanced green fluorescent protein that PLD1, which is largely associated with secretory granules, redistributes to the plasma membrane in stimulated cells by processes reminiscent of exocytosis and fusion of granules with the plasma membrane. (omitted)

  • PDF

Recent Developments of Polymer Electrolyte Membrane Fuel Cell Design

  • Wonchan Hwang;Yung-Eun Sung
    • Journal of Electrochemical Science and Technology
    • /
    • v.14 no.2
    • /
    • pp.120-130
    • /
    • 2023
  • PEMFC has high potential for future development due to its high energy density, eco-friendliness, and high energy efficiency. When it becomes small, light and flexible, it can be competitive as an energy source for portable devices or flexible electronic devices. However, the use of hard and heavy materials for structural rigidity and uniform contact pressure transmission has become an obstacle to reducing the weight and flexibility of PEMFCs. This review intends to provide an example of the application of a new structure and material for lightweight and flexibility. As a lightweight PEMFC, a tubular design is presented and structural advantages through numerical modeling are explained. Manufacturing methods to realize the structural advantages and possibilities of tubular PEMFCs are discussed. In addition, the materials and manufacturing processes used to fabricate lightweight and flexible PEMFCs are described and factors affecting performance are analyzed. Strategies and structural improvements of light and flexible movements are discussed according to the component parts.

Exposure Characteristics of Particles during the After-treatment Processes of Aluminum Oxide Fibers and Nickel Powders (산화알루미늄 섬유와 니켈분말 후처리공정에서 입자의 노출특성)

  • Kim, Jong Bum;Kim, Kyung Hwan;Ryu, Sung Hee;Yun, Seong-Taek;Bae, Gwi-Nam
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.26 no.2
    • /
    • pp.225-236
    • /
    • 2016
  • Objectives: Nanomaterials have been used in various fields. As use of nanoproducts is increasing, workers dealing with nanomaterials are also gradually increasing. Exposure assessments for nanomaterials have been carried out for protection of worker's health in workplace. Exposure studies were mainly focused on manufacturing processes, but these studies on after-treatment processes such as refinement, weighing, and packing were insufficient. So, we investigated exposure characteristics of particles during after-treatment processes of $Al_2O_3$ fibers and Ni powders. Methods: Mass-production of Ni powder process was carried out in enclosed capture-type canopy hood. In a developing stage, $Al_2O_3$ was handled with a local ventilation unit. Exposure characteristics of particles were investigated for $Al_2O_3$ fiber and Ni powder processes during the periods of 10:00 to 16:00, 20 May 2014 and 13:00 to 16:00, 21 May 2014, respectively. Three real-time aerosol instruments were utilized in exposure assessment. A scanning mobility particle sizer(SMPS, nanoscan, model 3910, TSI) and an optical particle counter(OPC, portable aerosol spectrometer, model 1.109, Grimm) were used to determine the particle size distribution in the size range of 10-420 nm and $0.25-32{\mu}m$, respectively. In addition, a nanoparticle aerosol monitor(NAM, model 9000, TSI) was used to measure lung-deposited nanoparticle surface area. Membrane filters(isopore membrane filter, pore size of 100 nm) were also used for air sampling for the FE-SEM(model S-5000H, Hitachi) analysis using a personal sampling pump(model GilAir Plus by 2.5 L/min, Gilian). Conclusions: For Ni powder after-treatment process, only 27% increase in particle concentration was found during the process. However, for $Al_2O_3$ fiber after-treatment process, significant exposure(1.56-3.34 times) was observed during the process.

Development of Techniques for Evaluating the Virus Removal Rate using Adenovirus (아데노바이러스를 이용한 바이러스 제거율 평가를 위한 기법 개발)

  • Cho, Yoonjung;Lim, Jaewon;Baek, Dawoon;Lee, Sang-Hoon;Lee, In-Soo;Lee, Hyeyoung;Park, Donghee;Jung, Dongju;Kim, Tae Ue
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.29 no.6
    • /
    • pp.633-641
    • /
    • 2015
  • Waterborne infectious disease is induced by several pathogenic microbes such as bacteria, viruses and protozoans, and the cases caused by viral infection is currently increasing. Water treatment process could reduce the number of virus in the water, but there were many difficulties to completely remove the virus particles from water. Therefore, the membrane separation technology which was reported to effectively remove pollutants from raw water has attracted increasing attention and demand. Since its efficiency has been introduced, demands for evaluation method toward the membrane filtration process are increasing. However, progression of the method development is slow due to the difficulties in cultivation of several waterborne viruses from animal models or cell culture system. To overcome the difficulties, we used adenovirus, one of the commonly isolated pathogenic waterborne viruses which can grow in cell culture system in vitro. The adenovirus used in this study was identified as human adenovirus C strain. The adenovirus was spiked in the raw water and passed through the microfiltration membrane produced by Econity, a Korean membrane company, and then the viral removal rate was evaluated by real-time PCR. In the results, the amount of virus in the filtered water was decreased approximately by 5 log scale. Because coagulant treatment has been known to reduce filtering function of the membrane by inducing fouling, we also investigated whether there was any interference of coagulant. In the results, we confirmed that coagulant treatment did not show significant interference on microfiltration membrane. In this study, we found that waterborne virus can be effectively removed by membrane filtration system. In particular, here we also suggest that real-time PCR method can rapidly, sensitively and quantitatively evaluate the removal rate of virus. These results may provide a standard method to qualifying membrane filtration processes.