• 제목/요약/키워드: Triple Layer

검색결과 165건 처리시간 0.029초

Surface Complexation Model을 이용한 양이온 중금속(Pb, Cd) 흡착반응의 모델화 연구 (Studies on the Adsorption Modeling of Cationic Heavy Metals(Pb, Cd) by the Surface Complexation Model)

  • 신용일;박상원
    • 한국환경과학회지
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    • 제8권2호
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    • pp.211-219
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    • 1999
  • Surface complexation models(SCMs) have been performed to predict metal ion adsorption behavior onto the mineral surface. Application of SCMs, however, requires a self-consistent approach to determine model parameter values. In this paper, in order to determine the metal ion adsorption parameters for the triple layer model(TLM) version of the SCM, we used the zeta potential data for Zeolite and Kaolinite, and the metal ion adsorption data for Pb(II) and Cd(II). Fitting parameters determined for the modeling were as follows ; total site concentration, site density, specific surface area, surface acidity constants, etc. Zeta potential as a new approach other than the acidic-alkalimetric titration method was adopted for simulation of adsorption phenomena. Some fitting parameters were determined by the trial and error method. Modeling approach was successful in quantitatively simulating adsorption behavior under various geochemical conditions.

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선천성 식도폐쇄 및 간식도루 1례 보 (Congenital Esophageal Atresia with Tracheoesophageal Fistula - A Case Report -)

  • 손동섭
    • Journal of Chest Surgery
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    • 제20권3호
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    • pp.565-569
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    • 1987
  • The first description of the pathologic anatomy of esophageal atresia was presented by Duration in 1670, it was not successfully treated until 1939 when the first two survivors of staged correction were described by Ladd and Levin. In 1941 Haight and Towsley performed the first successful primary repair. Recently we were experienced a case of esophageal atresia with tracheoesophageal fistula an infant patient who presented the symptoms of vomiting and dyspnea. The diagnosis was made by the esophagography with Diagnosis. The operation was performed extrapleurally through 4th intercostal space after gastrostomy. The fistula was closed by triple ligation and the upper pouch was then brought into apposition with the presenting surface of the lower esophageal segment and an end to side anastomosis was fashioned with a single layer of sutures. Operative patient tolerated all the operative procedure well in spite of postoperative respiratory complication and recovered uneventfully, permitted feeding on 9th postoperative day after esophagography.

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Surface Complexation Modeling of $UO_2^{2+}$Sorption onto Goethite and Kaolinite

  • Jinho Jung;Jae kwang lee;Cho, Yong-Hwan;Dong kwon Keum;Hahn, Pil-Soo
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(2)
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    • pp.453-457
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    • 1998
  • The sorption of UO$_2$$^{2+}$showed ionic strength independece for goethite and dependence for kaolinite. In the presence of carbonate, the sorption decreased in the weakly alkaline pH range becase of the formation of aqueous U(VI)-carbonate complexes. The sorption of UO$_2$$^{2+}$onto goethite and kaolinite under various experimental conditions was successfully interpreted using a surface complexation modeling, named triple layer model (TLM). The best fit to the experimental data was obtained by the FITEQL program, and then evaluated with available spectroscopic data. The results showed the versatility of surface complexation modeling over empirical one to predict UO$_2$$^{2+}$ sorption behavior.avior.

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Highly Efficient Simple-Structure Red Phosphorescent OLEDs with an Extremely Low Doping Technology

  • Jeon, Woo-Sik;Park, Tae-Jin;Kwon, Jang-Hyuk
    • Journal of Information Display
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    • 제10권2호
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    • pp.87-91
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    • 2009
  • Highly efficient red phosphorescent OLEDs (PHOLEDs) with a simple, organic, triple-layer structure was developed using the narrow-bandgap fluorescent host material bis(10-hydroxybenzo[h] quinolinato)beryllium complex (Bebq2) and the deep-red dopant tris(1-phenylisoquinoline)iridium (Ir(piq)3). The maximum current and power efficiency values of 12.71 cd/A and 16.02 lm/W, respectively, with an extremely low doping technology of 1%, are demonstrated herein. The results reveal a practical, cost-saving host dopant system for the fabrication of highly efficient PHOLEDs involving the simple structure presented herein, with a reduction of expensive Ir dopants.

토양내의 중금속이 유기오염물질 생분해에 미치는 영향 연구 (The influence of heavy metal on microbial biodegradation of organic contaminants in soil)

  • 최재영;박재우
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2000년도 추계학술대회
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    • pp.196-201
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    • 2000
  • The influence of adsorption on cadmium toxicity to soil microorganisms in smectite-rich soils and sediments was quantified as a function of solution and sorbent characteristics. Adsorption and surface complexation experiments were conducted to infer Cd sorption mechanisms to a reference smectite and three fractions of a Veritsol soil, and to elucidate the effects of the surface complexation on Cd bioavailability and toxicity in soils and sediments. Cadmium adsorption isotherms conformed to the Langmuir adsorption model, with adsorptive capacities of the different samples dependent on their characteristics. Equilibrium geochemical modeling (MINTEQA2) was used to predict the speciation of Cd in the soil suspensions using Langmuir and Triple Layer surface complexation models. The influence of adsorption and surface complexation on cadmium toxicity to soil microorganisms was assessed indirectly through the relative change in microbial hydrolysis of fluorescein diacetate (FDA) as a function of total Cd concentration and sorbent characteristics. Adsorption decreased the toxicity of Cd to soil microorganisms. Inner-sphere complexation is more effective than outer-sphere complexation in reducing the bioavailability and toxicity of heavy metals in soils and sediments.

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How Shock Wave Interacts with a Vortex ?

  • Chang Keun-Shik;Chang Se-Myong
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2004년도 춘계학술대회 논문집
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    • pp.1-7
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    • 2004
  • When a vortex diffracts upon encountering a vortex, many strong and weak waves are produced in the course of interaction. They are the cause of shock wave attenuation and noise production. This phenomenon is fundamental to understanding the more complex supersonic turbulent Jet noise. In this paper we have reviewed the research on shock-vortex interaction we have carried on last seven years. We have computationally investigated the parameter effect. When a shock is strong, shock diffraction pattern becomes complex since the slip lines from the triple points on Mach stem curl into the vortex, causing an entropy layer. When the vortex is unstable, vortexlets are brought about each of which make shock diffraction of a reduced intensity. Strong vortex produces quadrupole noise as it impinges into a vortex. Elementary interaction models such as shock splitting, shock reflection, and shock penetration are presented based on shock tube experiment. These models are also verified by computational approach. They easily explain production and propagation of the aforementioned quadrupole noise, Diverging acoustics are explained in terms of shock-vortexlet interactions for which a computational model Is constructed.

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Spectroscopic ellipsometer를 이용한 삼원 SiO박막의 증착조건에 따른 유전율 특성 (The dielectric properties of triple SiO thin film using spectroscopic ellipsometer)

  • 김창석;황석영
    • E2M - 전기 전자와 첨단 소재
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    • 제8권2호
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    • pp.129-135
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    • 1995
  • SiO thin films are deposited by evaporator the refractive index of wave length, photon energy and the absorptive rate of these films are measured by spectroscopic ellipsometer. It is derived the absorptive rate and permitivity of SiO thin films from the equations that calculating the refractive index. And the result show good agreement with the calculated values and experimental values. As a result, the wave length of light is increased in the condition that the angle of incidence is fixed on SiO thin film, the basic absorption and the absorption impurities are found in the low wave length (below 450 nm in this study) and the reflective absorption and conductive absorption is increased by the form of exponential function over the low wavelength. The absorptive rate is increased by increased the angle of incidence and thickness of SiO film for the insulating layer. As the thickness of SiO film is increased, the value of complex permitivity is decreasing and as wave length of incidence is increased., the value of dielectric is linearly increasing.

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새로운 발광물질인 PRL-401, 403을 사용한 EL소자의 특성분석 (The characteristics of the electroluminescent devices using new organic materials, PRL-401, 403)

  • 김준호;이상필;이광섭;김영관;김정수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 C
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    • pp.1742-1744
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    • 2000
  • Organic materials have been considered for the fabrication of practical electroluminescent(EL) devices because a large number of organic materials are known to have extremely high fluorescence quantum efficiencies in the visible spectrum. In this study, electroluminescent devices are constructed using novel organic materials PRL-401, PRL-403 as the emitting elements. The devices have a triple-layer structure of organic thin films, prepared by vacuum vapor deposition. Greenish yellow electroluminescent emission is observed. The maximum luminances are over 1000 $cd/m^2$ and the turn-on voltages are about 13 V.

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Spectroscopic Ellipsometer를 이용한 삼원 SiO박막의 유전율특성 (The Dielectric Properties by Triple SiO Thin Film using Spectroscopic Ellipsometer)

  • 김병인;이우선;김창석;이상일;황석영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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    • pp.249-251
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    • 1994
  • We fabricated the sample of M-I-M with the insulating layer SiO. Refractive index of wave length, photon energy, absorption rate of SiO evaporation thin film are experimentally examined by spectroscopic Ellipsometer. The calculated equations of refractive index, absorption rate and permittivity of SiO thin film are induced. Calculated values and experimental values are compared and then mutual validity is proved.

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Two d10 Metal Coordination Polymers Based on 1H-1,2,4-Triazole: Synthesis, Structure and Fluorescence

  • Zhang, Xiu-Cheng;Xu, Ling;Liu, Wen-Guang;Liu, Bing
    • Bulletin of the Korean Chemical Society
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    • 제32권5호
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    • pp.1692-1696
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    • 2011
  • The reactions of 1H-1,2,4-triazole (Htr) with $MX_2$ ($ZnCl_2$ for 1; $CdBr_2$ for 2) resulted in two coordination polymers, [Zn(tr)Cl]$_n$ (1) and $[Cd(Htr)_2Br_2]_n$ (2). The structural analyses indicate that 1 and 2 feature a 2D layer and 1D triple chain, respectively. In 1, neighouring Zn atoms are connected by ${\mu}_3-1$ ${\kappa}N$: 2 ${\kappa}N$: $4{\kappa}N-tr^-$ anionic ligand into 6- and 16-membered rings, further grow into a 2D sheet. Cd atoms in 2 are bonded by two ${\mu}_2-Br^-$ bridges and neutral ${\mu}_2$-1 ${\kappa}N$: 2 ${\kappa}N$-Htr to form a 1D triple chain. The fluorescent characterizations of 1, 2 and the free Htr ligand feature simlilar emission peakes at 444, 446 and 423 nm respectively, which can be assigned to intra-ligand ${\pi}-{\pi}^*$ transition of (H)tr. The energy gaps of 5.90 eV for 1, 5.16 eV for 2, and 5.93 eV for Htr suggest that the compounds behave as insulators.