• Title/Summary/Keyword: Transport Property

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EMI shielding Effectiveness and the Physical Properties of Commercial EMI shielding Fabrics (시판 전자기파 차단 직물의 차폐효과 및 물성)

  • 한은경;오경화;김은애
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.5
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    • pp.694-702
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    • 1999
  • By using commercial available electromagnetic interference (EMI) shielding fabrics, EMI shielding effectiveness(SE) and the physical properties were investigated. Thirteen specimens were chosen six fabrics were non-electrolytic plated with Cu, six plated with Cu+Ni and one plated with Ni, SE was measured by RF Impedance Analyzer HP4291A(Hewlett Co, Ltd)at the frequency of 100MHz-1.8GHz. The results showed that the commercial EMI shielding fabrics provided SE values over 30dB at the frequency of 100MHz-1.8GHz. Fabrics plated with Cu showed more effective shielding than those plated with Ni. The thickness of coating and fabric count were also influential factors on SE. Tensile properties were acceptable for lining fabrics but water vapor transport properties indicated that the better treatment condition were suggested to improve comfort properties.

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Synthesis of Hole Transport Materials for Organic Light Emitting Device (유기발광디바이스용 정공수송재료의 합성)

  • Chung, Pyung-Jin;Cho, Min-Ju
    • Korean Journal of Materials Research
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    • v.15 no.7
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    • pp.448-452
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    • 2005
  • This study was based on organic electroluminescence display. Especially, TPD and $\alpha-NPD$ for the hole transport materials were synthesized by Ullmann reaction. This reaction was conducted between 3­methylphenylamine, 1-naphthylamine and 4,4'-diiodobiphenyl in toluene containing CuCl catalyst and KOH base. The structural property of reaction products were analyzed by FT-IR, $^1H-NMR$ spectroscopy, and thermal stability, reactivity and PL property were analyzed by melting point, yield and emission spectrum, respectively. The photoluminescence spectra of a pure TPD and $\alpha-NPD$ were observed at approximately 416nm and 438nm respectively. In this study, it was known that the melting point, yield, PL properties of TPD and $\alpha-NPD$ were changed by substituent group of amines.

Effect of Porosity Characteristics of Hollow Composite Yarns to the Comfort Property of the Fabrics for the High Emotional Garment (중공 복합사 직물의 기공도 특성이 고감성 의류용 직물의 쾌적특성에 미치는 영향)

  • Kim, Hyun Ah;Kim, Young Soo;Kim, Seung Jin
    • Textile Coloration and Finishing
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    • v.26 no.3
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    • pp.218-229
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    • 2014
  • The wearing comfort of garment is governed by two kinds of characteristics such as moisture and thermal transport properties and mechanical properties of fabrics. The porosity influenced by yarn and fabric structural parameters is known as main factor for wearing comfort of garment related to the moisture and thermal transport properties. This study investigated effect of porosity of composite yarns to the moisture and thermal comfort properties of composite fabrics made of hollow composite DTY and ATY yarns. The theoretical porosity and pore size were inversely proportional to cover factor of fabric, but cover factor was not correlated with experimental pore size. The wicking property of hydrophobic PET filament fabric showed inferior result irrespective of porosity, pore size and cover factor. The drying rate was superior at composite fabrics with high pore size and low cover factor, and pore size was dominant factor for drying property. On the other hand, thermal conductivity of composite fabric was mainly influenced by cover factor and not influenced by porosity. Air permeability was influenced by both porosity and cover factor and was highly increased with increasing porosity and decreasing fabric cover factor.

Clinical Study for Mucociliary clearance of Pediatric Chronic Sinusitis after KamiHyunggyeyungotang Therapy (가미형개연교탕(加味荊芥蓮翹湯)이 만성부비동염(慢性副鼻洞炎)의 비강섬모운동(鼻腔纖毛運動)에 미치는 영향(影響))

  • Yang, Mi-Ra;Park, Eun-Jeung;Im, Tae-Hyung;Jin, Kyong-Sun
    • The Journal of Pediatrics of Korean Medicine
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    • v.17 no.1
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    • pp.1-16
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    • 2003
  • Background: Delayed mucociliary clearance develops the pooling of nasal secretion in the nasal cavity and is a common cause of vicious cycle of symptoms in chronic sinusitis. mucociliary clearance depends on the ciliary activity, the rheological property of the secretion and on the interaction between cilia and the mucous blanket. Objective: To demonstrate the therapeutic effect of herbal medicine (Hyunggyeyungotang) on the mucociliary transport in the chronic sinusitis using saccharine Materials and methods: Forty patients treated in our hospital between september 2000 and september 2001 were studied. Before and after therapy group are composed of twenty patients. Kamihyunggyeyungyotang was administered mainly. We analyzed the saccharine mucociliary transport time of patients. Results: 1) In the control group, the transport time is about 13.4 minutes. 2) In chronic sinusitis before Kamihyunggyeyungotang therapy, the transport time is about 27.7 minutes. 3) In chronic sinusitis after Kamihyunggyeyungotang therapy, the transport time is about 13.8 minutes. Conclusion: Delayed mucociliary transport time in chronic sinusitis is earlier after Kamihyunggyeyungotang therapy.

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Low voltage organic light-emitting devices with new electron transport layer

  • Ha, Mi-Young;Kim, So-Youn;Moon, Dae-Gyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.679-682
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    • 2007
  • We have developed low voltage operating OLEDs with new electron transport layer. The device having a structure of ITO/2TNATA/HTL:Rubrene(1%)/HTL /new ETL/LiF/Al have been used. The voltage for achieving $1,000\;cd/m^2$ was 4.1 V, whereas the turn on voltage for the brightness of $1\;cd/m^2$ was 2.8 V. This high luminance at low operating voltage is caused by the high current density, resulting from high electron conduction property of the new electron transport layer.

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Effects of Mixing Characteristics at Fracture Intersections on Network-Scale Solute Transport

  • 박영진;이강근
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.11a
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    • pp.69-73
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    • 2000
  • We systematically analyze the influence of fracture junction, solute transfer characteristics on transport patterns in discrete, two-dimensional fracture network models. Regular lattices and random fracture networks with power-law length distributions are considered in conjunction with particle tracking methods. Solute transfer probabilities at fracture junctions are determined from analytical considerations and from simple complete mixing and streamline routing models. For regular fracture networks, mixing conditions at fracture junctions are always dominated by either complete mixing or streamline routing end member cases. Moreover bulk transport properties such as the spreading and the dilution of solute are highly sensitive to the mixing rule. However in power-law length networks there is no significant difference in bulk transport properties, as calculated by assuming either of the two extreme mixing rules. This apparent discrepancy between the effects of mixing properties at fracture junctions in regular and random fracture networks is explained by the statistics of the coordination number and of the flow conditions at fracture intersections. We suggest that the influence of mixing rules on bulk solute transport could be important in systematic orthogonal fracture networks but insignificant in random networks.

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Bending Strain Effect on the Critical Current of Jointed BSCCO Tapes

  • Shin, Hyung-Seop;Dedicatoria, Marlon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.217-217
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    • 2009
  • In this study, the effect of bending strain on the transport property and critical current of lap and butt-jointed BSCCO tapes have been investigated. The samples were joined using a mechanically controlled jointing procedure. In order to ensure a uniform pressure application at the joint part, a single point contact has been devised and also to achieve a uniform thickness at the joint interface.

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Electrical Property of Polyvinylalcohol (Polyvinylalcohol의 전기적 특성)

  • 김현철;김종욱;구할본
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.156-159
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    • 1994
  • The electrical property of polyvinylalcohol (PVA) films (several hundreds ∼ several $\mu\textrm{m}$ in thickness) formed by sphere bulb blowing technique, has been studied. The electrical conductivity of relatively thick films (>several thousands ) has been very high and enhanced by the exposure either to high humidity fo air or NH$_3$. which can be explained in terms of the role of ionic transport. The use of PVA film as NH$_3$ sensor is also proposed. In PVA films less than 1500 , two conducting states: high conducting and low conducting states, are observed.

Charge-Carrier Transport Properties and Fluorescence Behaviors Depending on Charge Transport Complex of Organic Photoconductor Containing Liquid Crystal (액정을 함유하는 유기 광도점체의 전하 수송착체에 의한 Charge-Carrier수송 특성과 형광거동)

  • Lee, Bong; Jung, Sung-Young;Moon, Doo-Dyung
    • Polymer(Korea)
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    • v.25 no.5
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    • pp.719-727
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    • 2001
  • Recently it was found that the charge carrier transport properties are significantly enhanced due to effective intermolecular $\pi$-orbital overlapping and low disorder of hopping sites caused by self-organization of liquid crystal molecules. In this study, the xerographic properties of a double-layer photoconductor doped with nematic liquid crystal, 4-pentyl-4'-cyanoterphenyl (5CT), as a charge-carrier transport material to enhance the charge-tarrier mobility were investigated. From the results of measured surface voltage properties for the photoconductor doped with various concentrations of liquid crystal, 5CT, the initial voltage was found to increase with the concentration of 5CT and the dark decay decreased with the concentration of 5CT. The highest sensitivity was obtained at a specific concentration, 40wt% 5CT. The fluorescence behavior of the carrier transport layer (CTL) was also investigated. It was found that the charge-carrier transport properties of the organic photoconductor depend on the charge-carrier transport properties of the complex. The TNF : 5CT (40 wt%) and OXD : 5CT (40 wt%)samples showed the highest sensitivity because the greatest charge transport complex was termed between the charge-carrier transport materials in these samples.

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Determining Economic Speed for Green Freight Train (저탄소 화물열차를 위한 경제속도 결정에 관한 연구)

  • Kim, Kwang-Tae;Choi, Won-Suk;Kim, Young-Hoon;Lee, Sun-Young
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.461-464
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    • 2011
  • Rail transport has been considered as an environmental-friendly transport mode compared with other transport modes such as ship, truck, and aircraft. However, rail industry can not avoid a duty of alleviating Greenhouse gases emission owing to the Korean government polices for green growth which is an economic paradigm that simultaneously pursues growth and environmental improvement. The purpose of this research is to develop a methodology of determining an economic speed of freight train to be green freight train by considering fuel cost, environmental cost, and time cost. In the methodology, we first define a cost function based on cost factors and then suggest an economic speed of freight train by deriving a property.

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