• 제목/요약/키워드: Absorption/Adsorption

검색결과 351건 처리시간 0.028초

Alachlor 와 Paraquat 의 토양흡착(土壤吸着)에 관여(關與)하는 토양인자(土壤因子)에 대한 연구(硏究) (Studies on the Several Soil Factors Affecting on Alachlor and Paraquat Adsorption by Soils)

  • 임수길;봉원애
    • 한국환경농학회지
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    • 제11권2호
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    • pp.101-108
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    • 1992
  • 토양에 따른 제초제의 흡착을 구명하기 위하여 alachlor와 paraquat를 사용하여 공시토양 22에 대한 약제별 흡착정도 및 토양특성과 흡착정도의 상관을 조사한 결과는 다음과 같다. 1. 진탕시간에 따른 토양과 약제의 평형이 이루어지는 시간은 paraquat가 약 30분, alachlor는 약 4시간이었다. 2. 분배법칙에 의한 alachlor의 흡착계수는 5ppm 농도에서 0.81-33.83이었으며, 50ppm에서는 0.09-15.52의 범위를 나타내었다. 3. 토양특성중 alachlor의 흡착력은 O.M.함량, paraquat의 흡착력은 점토함량과 고도의 정의 상관을 보였다. 4. 우리나라 토양중 춘포통은 유기물과 점토함량이 낮음에도 특이한 특성 때문에 paraquat와 alachlor 모두 높은 흡착량을 나타내었다. 5. Freundlich의 흡착상수(K)는 분배법칙의 계수(Kd)보다 대체적으로 높으며, 평형농도가 증가함에 따라 K와 Kd값의 차이는 증가하는 경향이었다.

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황화수소(H2S) 흡착성능 증진을 위한 하수슬러지 기반 흡착제 탄화조건 최적화 연구 (A study on the Optimization of Sewage Sludge-based Adsorbent Carbonization Condition for Improving Adsorption Capacity of Hydrogen Sulfide (H2S))

  • 최성열;장영희;김성수
    • 공업화학
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    • 제29권6호
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    • pp.765-771
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    • 2018
  • 본 연구에서는 각종 환경기초시설에서 발생하는 악취 유발물질 중 $H_2S$를 처리하기 위한 하수슬러지 기반 흡착제의 흡착성능 증진을 위해 제조조건 중 탄화조건 최적화에 대한 연구를 수행하였다. 적용되는 흡착제는 하수처리장에서 발생하는 슬러지를 온도 및 승온속도와 같은 탄화조건을 달리하여 제조하였으며, 흡착제의 물리적 특성과 흡착성능과의 상관관계를 확인하였다. 실험결과 $10^{\circ}C/min$의 승온속도로 $900^{\circ}C$의 온도에서 탄화과정을 거친 슬러지의 흡착성능이 가장 우수하였으며, SEM, BET 분석을 통해 비표면적 및 기공특성(기공크기, 부피)이 흡착성능의 주요 인자임을 확인하였다. 최적 탄화조건 흡착제의 흡착성능을 증진시키기 위해 K 이온을 담지하였으나, 하수슬러지 기반 흡착제의 경우 큰 영향이 없는 것으로 확인하였다.

Enhancement of Dye Adsorption on TiO2 Surface through Hydroxylation Process for Dye-sensitized Solar Cells

  • Jang, Inseok;Song, Kyungho;Park, Jun-Hwan;Oh, Seong-Geun
    • Bulletin of the Korean Chemical Society
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    • 제34권10호
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    • pp.2883-2888
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    • 2013
  • To enhance the power conversion efficiency of dye-sensitized solar cell (DSSC), the surface of titanium dioxide ($TiO_2$) photoelectrode was modified by hydroxylation treatment with $NH_4OH$ solution at $70^{\circ}C$ for 6 h. The $NH_4OH$ solutions of various concentrations were used to introduce the hydroxyl groups on $TiO_2$ surface. As the concentration of $NH_4OH$ was increased, the short-circuit current density ($J_{SC}$) value and conversion efficiency of solar cells were increased because the amount of adsorbed dye molecules on $TiO_2$ surface was increased. As a result of the surface modification to introduce hydroxyl groups, the concentration of adsorbed dye on the $TiO_2$ surface could be improved up to 32.61% without the changes of morphology, surface area and pore volume of particles. The morphology, the specific surface area, the pore volume and the chemical states of $TiO_2$ surface were characterized by using FE-SEM, $N_2$ adsorption-desorption isotherms and XPS measurements. The amount of adsorbed dye and the performance of fabricated cells were analyzed by using UV-Vis absorption spectroscopy and solar simulator.

분말활성탄을 활용한 미세먼지 흡착형 경화체의 물리적 특성 (Physical Properties of Fine Dust Adsorption Matrix using Powder Activate Carbon)

  • 이원규;김연호;경인수;이상수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 추계 학술논문 발표대회
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    • pp.172-173
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    • 2019
  • As the damage to fine dust increased, the Republic of Korea designated fine dust as a social disaster. The composition of the fine dust is composed of carbon, sulfate, nitrate, ammonium and minerals. The cause of fine dust is naturally generated by dirt, pollen, etc. In addition, there are artificial causes such as gaseous vehicle exhaust gas emitted from the use of fossil fuel. When fine dust enters the human body through breathing, it causes various respiratory diseases and skin diseases. In IARC, fine dust was designated as a carcinogen group 1. In this research, we tried to adsorb fine dust by physical adsorption using powdered activate carbon. Powdered activate carbon is a powdered activated carbon activated in a carbonized state. Porous material with high specific surface area and low density. Experimental items were tested for density, water absorption, and fine dust concentration according to the PAC addition ratio. Basic experiments were carried out to fabricate the fine dust adsorption matrix.

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휘발성 유기 화합물(VOCs) 처리 기술 (Technologies for Volatile Organic Compounds(VOCs) Treatment)

  • 서봉국;나영수;송승구
    • 한국환경과학회지
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    • 제12권7호
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    • pp.825-833
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    • 2003
  • The emission of volatile organic compounds (VOCs) generated from painting and coating processes is a worldwide problem as contributing factors to the development of photochemical smog and other environmental problems. Common methods of reducing VOC emissions are adsorption on activated carbon, membrane separation, absorption, incineration, or catalytic oxidation. In this article, the environmental issues caused by VOC emissions and the trend of legislation against such emissions will be surveyed first. Several conventional control technologies will then be summarized and the characteristics of each process will be introduced. Lastly, some examples will be described to show the hybrid processes which have been industrially applied for the recovery of VOC.

Adsorption Characteristics of Furan, Thiophene, and Selenophene on Si(100) Surface

  • Park, Jinwoo;Lee, Han-Koo;Chung, J.W.;Hong, Suklyun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.202.2-202.2
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    • 2014
  • We have studied the bonding structures of five membered aromatic ring heterocyclic molecules, such as furan, thiophene, and selenophene, adsorbed on the Si(100) surface at room temperature with density functional theory. Additionally, we have investigated the evolution upon annealing of thiophene and selenophene molecules on the Si(100) surface by the core-level photoemission spectroscopy and near-edge X-ray absorption fine structure (NEXAFS). The core-level-spectra measured at different temperatures are consistently interpreted in terms of various adsorption structures suggested by theoretical calculations. In this study, we found the most suitable structures by theoretical and experimental results considering room temperature and mild thermal annealing.

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Ag-modified BiOX (X=Cl, Br and I) Plates for Photocatalytic Dye Removal

  • 이승원;최영인;이주헌;박요한;손영구
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.424.2-424.2
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    • 2014
  • Ag-modified BiOX (X=Cl, Br and I) nanoplates were synthesized by an ion-exchange reaction. We examined the fundamental properties by scanning electron microscopy (SEM), electron transmission microscopy (TEM), X-ray diffraction, UV-visible absorption, Fourier-transform infrared and photoluminescence spectroscopy. The adsorption and photocatalytic performances of the catalysts were tested with dyes under UV and visible light. A chemical scavenger method was employed to test the roles of active species (${\cdot}OH$, ${\cdot}O2-$ and h+) and understand photodegradation mechanism. Photoluminescence spectroscopy was used to examine ${\cdot}OH$ radical formation using terephthalic acid during photoirradiation.

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Ozone Density Estimation and Stable Supply in the Thin Film Growth

  • Lim, Jung-Kwan;Park, Yong-Pil;Oh, Geum-Gon
    • Transactions on Electrical and Electronic Materials
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    • 제2권2호
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    • pp.42-45
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    • 2001
  • An ozone condensation system is evaluated from the viewpoint of an ozone supplier for Bi-superconductor thin film growth. An ozone condenser by a selective adsorption on the silica gel surface is constructed. Ozone density is evaluated by three methods; ultraviolet absorption, thermal decomposition and Q-mass analyzing methods. Thermal decomposition method is found to be available to the density evaluation from dilute to highly condensed ozone. The highest ozone density condensed by the adsorption method is evaluated to be 97 mol%.

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초전도 박막 제작을 위한 산화 시스템의 특성( II ) (Characteristics of Oxidation System for Superconductor Thin Film( II ))

  • 안인순;박용필;임중관;장경욱;이희갑;김귀열;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.264-267
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    • 2002
  • An ozone condensation system is evaluated from the viewpoint of an ozone supplier for oxide thin film growth. Ozone is condensed by the adsorption method and its concentration is analyzed by three methods; ultraviolet absorption, thermal decomposition and Q-mass analyzing methods. Thermal decomposition method is found to be available to the concentration evaluation from dilution to highly condensed ozone. The highest ozone concentration condensed by the adsorption method is evaluated to be 97 mol%

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초전도 박막 제작을 위한 산화 시스템의 특성( I ) (Characteristics of Oxidation System for Superconductor Thin Film( I ))

  • 임중관;박용필;양동복;김정호;이희갑;박노봉
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.272-275
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    • 2002
  • An ozone condensation system is evaluated in the viewpoint of an ozone supplier for oxide thin film growth. Ozone is condensed by the adsorption and distillation method. Then their concentrations are analyzed by three methods; ultraviolet absorption, thermal decomposition and Q-mass analyzing methods. Thermal decomposition method is found to be available to the concentration evaluation from dilution to highly condensed ozone. The highest ozone concentration condensed by the adsorption method is evaluated to be 96 mol%. The ozone is supplied for a sufficiently long time to grow oxide thin films.

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