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HYPOLED - VGA OLED micro-display for HMD and microprojection

  • Vogel, Uwe;Underwood, Ian;Notni, Gunther;Zilstorff, Christian;Meerholz, Klaus;Haas, Gunther
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.404-407
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    • 2009
  • HYPOLED is a collaborative European project that commenced in 2008. It is targeted toward "High-Performance OLED-Microdisplays for Mobile Multimedia HMD and Projection Applications". In this paper, we describe the initial objectives and present draft specifications for devices, the personal display system and micro-projection unit. Initial results are shown and discussed.

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Recent Progress in Qantum Dots Containing Thin Film Composite Membrane for Water Purification (양자점이 합체된 복합 박막을 이용한 정수의 최근 발전)

  • Park, Shinyoung;Patel, Rajkumar
    • Membrane Journal
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    • v.30 no.5
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    • pp.293-306
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    • 2020
  • Increasing harmful effects of climate change, such as its effect on water scarcity, has led to a focus on developing effective water purification methods to obtain pure water. Additionally, rising levels of water pollution is increasing levels of environmental degradation, calling for sources of water treatment to remove contaminants. To purify water, osmotic processes across a semipermeable membrane can take place, and recent studies are showing that incorporating nanoparticles, including carbon quantum dots (CQDs), graphene carbon dots (GQDs), and graphene oxide quantum dots (GOQDs) are making thin film composite (TFC) membranes more effective by increasing water flux while maintaining similar levels of salt rejection, increasing the hydrophilicity of the membrane surface, showing bactericidal properties, exhibiting antifouling properties to prevent accumulation of bacteria or other microorganisms from reducing the effectiveness of the membrane, and more. In the review, the synthesis process, applications, functionality, properties, and the role of several types of quantum dots are discussed in the composite membrane for water purification.

Ionic Liquid based Carbon Dioxide Separation Membrane (이온성 액체를 이용한 이산화탄소 분리막)

  • Park, Jung Hyeok;Patel, Rajkumar
    • Membrane Journal
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    • v.30 no.3
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    • pp.149-157
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    • 2020
  • Ionic Liquid (IL) in the category of low-temperature molten salts with organic cation and organic/inorganic anion has shown great potentiality in CO2 gas separation. CO2 gas separation from flue gas by IL based membrane has been widely researched in recent years to overcome climate change and global warming. Membranes based on free standing polyionic liquid (PIL), blend of ionic liquid and composite ionic liquid membranes are discussed in this review. Introducing different IL monomers and tuning microstructure of PIL membrane and composite of PIL-IL to enhance mechanical properties of membranes with good CO2 gas permeability and selectivity. Variations in cation and anions of monomer has great impact on the membrane gas separation performance.

Review on Proton Exchange Membranes for Microbial Fuel Cell Application (미생물 연료 전지 적용을 위한 양성자 교환막에 대한 검토)

  • Kim, Ji Min;Patel, Rajkumar
    • Membrane Journal
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    • v.30 no.4
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    • pp.213-227
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    • 2020
  • As unrenewable energy resources have depleted over the years, the demand for renewable energy has increased promoting research for more effective methods to produce renewable energy. The field of fuel cell development, specifically microbial fuel cells (MFCs), has developed because of the dual performance potential of the technology. MFCs convert power by facilitating electrode-reducing organisms such as bacteria (microbes) as a catalyst to produce electrical energy. MFCs use domestic and industrial wastewater as fuel to initiate the process, purifying the wastewater as a result. Proton exchange membranes (PEM) play a crucial role in MFCs as a separator between the anodes and cathodes chambers allowing only protons to effectively pass through. Nafion is the commercially used PEM for MFCs, but there are many setbacks: such as cost, production time, and less effective proton conductivity properties. In this review there will be largely two parts. Firstly, several newly developed PEM are discussed as possible replacements of Nafion. Secondly, MFC based on PEM, blended PEM and composite PEM are summarized.

The Study of Structure Design for Dividing Wall Distillation Column (분리벽형 증류탑의 구조 설계 및 분리 특성 연구)

  • Lee, Seung Hyun;Lee, Moon Yong
    • Korean Chemical Engineering Research
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    • v.45 no.1
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    • pp.39-45
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    • 2007
  • This paper proposed a shortcut method for the structure design of dividing wall column based on the Fen-ske-Underwood equation by applying it on three conventional simple column configuration. It is shown that the proposed shortcut method can design the column structure including the feed tray, dividing wall section, and side-stream tray in a simple and efficient way in the initial design stage. Simulation study using HYSYS to compare the energy saving performance between the conventional sequential two column system and the dividing wall column designed by the proposed method shows that the proposed dividing wall column system saves from 16% to 65% more over the condepends on the composition of intermediate component while the optimal energy consumption pattern to internal flow distribution on the dividing wall section is characterized by the ESI factor of the feed mixture.

Oil/Water Separation Technology by MXene Composite Membrane: A Review (MXene 복합막에 의한 기름/물 분리 기술: 총설)

  • Lee, Byunghee;Patel, Rajkumar
    • Membrane Journal
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    • v.31 no.5
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    • pp.304-314
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    • 2021
  • Climate change results in unusual weather pattern and affects annual rain fall severely. At the same time, growing industrialization leads to higher energy demand and leakage from petrochemical industry and tanker leads to water pollution. In this scenario, finding out solution to generate clean water is highly essential. For oil/water separation, there are several methods available such as chemical precipitation and adsorption but membrane separation technique is considered to be a more cost and energy efficient process. Amphiphilicity nature of membrane are enhanced by making composite membrane with 2D material such as MXene, resulting in good electrical conductivity and hydrophilicity. This review is mainly classified into two sections: pure MXene and modified MXene. A variety of polymer is used to prepare composite membranes and MXene is modified to further enhance the properties suitable for particular applications.

A Review on Lithium Recovery by Membrane Process (멤브레인 공정에 의한 리튬 회수에 대한 총설)

  • Kim, Esther;Patel, Rajkumar
    • Membrane Journal
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    • v.31 no.5
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    • pp.315-326
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    • 2021
  • Lithium ion battery (LIB) demands increase every year globally to reduce the burden on fossil fuels. LIBs are used in electric vehicles, stationary storage systems and various other applications. Lithium is available in seawater, salt lakes, and brines and its extraction using environmentally friendly and inexpensive methods will greatly relieve the pressure in lithium mining. Membrane separation processes, mainly nanofiltration (NF), is an effective way for the separation of lithium metal from solutions. Electrodialysis and electrolysis are other separation processes used for lithium separation. The process of reverse osmosis (RO) is already a well-established method for the desalination of seawater; therefore, modifying RO membranes to target lithium metals is an excellent alternative method in which the only bottleneck is the interfering presence of other metal elements in the solution. Selectively removing lithium by finding or developing suitable NF membranes can be challenging, but it is nonetheless an exciting area of research. This review discusses in detail about lithium recovery via nanofiltration, electrodialysis, electrolysis and other processes.

Review on Membranes Containing Silver Nanoparticles with Antibacterial and Antifouling Properties (항균 및 방오 특성을 가진 은나노 입자 함유 분리막에 대한 총설)

  • Kim, HanSol;Patel, Rajkumar;Kim, Jong Hak
    • Membrane Journal
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    • v.31 no.5
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    • pp.293-303
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    • 2021
  • Separation membranes used in water filtration, protein purification or biomedical filtration device frequently undergo membrane fouling for several reasons. The formation of biofilm on the membrane surface by bacteria causes a severe problem for durability of the membrane. For the protein separation, the membrane pores get blocked due to surface hydrophobicity of the membrane. There are several approaches controlling the membrane fouling and one of them is the incorporation of silver nanoparticles. Antibacterial properties of silver nanoparticles are well known and thus widely used in several applications. In this review, we have focused on the membranes where silver nanoparticles or its derivatives are either incorporated in the active layer of thin film composite membranes or uniformly distributed throughout the whole membranes.

Nanofiber Membrane based Colorimetric Sensor for Mercury (II) Detection: A Review (나노 섬유 멤브레인을 기반으로 한 수은(II) 색변화 검출 센서에 대한 총설)

  • Bhang, Saeyun;Patel, Rajkumar
    • Membrane Journal
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    • v.31 no.4
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    • pp.241-252
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    • 2021
  • Rapid industrialization with growing population leads to environmental water pollution. Demand in generation of clean water from waste water is ever increasing by scarcity of rain water due to change in weather pattern. Colorimetric detection of heavy metal present in clean water is very simple and effective technique. In this review membrane based colorimetric detection of mercury (II) ions are discussed in details. Membrane such as cellulose, polycaprolactone, chitosan, polysulfone etc., are used as support for metal ion detection. Nanofiber based materials have wide range of applications in energy, environment and biomedical research. Membranes made up of nanofiber consist up plenty of functional groups available in the polymer along with large surface area and high porosity. As a result, it is easy for surface modification and grafting of ligand on the fiber surface enhanced nanoparticles attachment.

Recent Progress in Patterned Membranes for Membrane-Based Separation Process (분리공정을 위한 패턴화 멤브레인 최근 연구 동향)

  • Aung, Hein Htet;Patel, Rajkumar
    • Membrane Journal
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    • v.31 no.3
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    • pp.170-183
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    • 2021
  • Fouling has continued to be a problem that hinders the effectiveness of membrane properties. To solve this problem of reducing fouling effects on membrane surface properties, different and innovative types of membrane patterning has been proposed. This article reviews on the progress of patterned membranes and their separation process concerning the fouling effects of membranes. The types of separation processes that utilize the maximum effectiveness of the patterned membranes include nanofiltration (NF), reverse osmosis (RO), microfiltration (MF), ultrafiltration (UF), and pervaporation (PV). Using these separation processes have shown and prove to have a major effect on reducing fouling effects, and in addition, they also add beneficial properties to the patterned membranes. Each patterned membrane and their separation processes gave notable results in threshold towards flux, salt rejections, hydrophilicity and much more, but there are also some unsolved cases to be pointed out. In this review, the effects of patterned membrane for separation processes will be discussed.