• Title/Summary/Keyword: Absorption/Adsorption

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Reaction of NO on Vanadium Oxide Surfaces: Observation of the NO Dimer Formation

  • Jeong, Hyun-Suck;Kim, Chang-Min
    • Bulletin of the Korean Chemical Society
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    • v.28 no.3
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    • pp.413-416
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    • 2007
  • The adsorption and surface reactions of NO on a VO/V(110) surface have been investigated using X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure, and temperature programmed desorption (TPD) technique. NO is molecularly adsorbed on VO/V(110) at 80 K. As the surface coverage of NO increases, the NO dimer is formed on the surface at 80 K. Both NO and (NO)2 are adsorbed on the surface with the N-O bond perpendicular to the surface. (NO)2 decomposes at ~100 K and the reaction product is desorbed as N2O. Decomposition of NO takes place when the surface temperature is higher than 273 K.

Solar Cooling Technology (태양열 냉방 시스템)

  • Baek, Nam-Choon
    • Solar Energy
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    • v.18 no.2
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    • pp.31-49
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    • 1998
  • Four main solar cooling technologies have been developed over the past twenty years are considered in this paper. These technologies include absorption, vapor compression, desiccant, adsorption, etc. All of these solar cooling technologies considered here are solar thermal ones. The destails of the thermodynamic cycle of these solar cooling technologies are given. The general concept of these solar cooling and the relative advantages among them are also presented. At last, the status and outlook for each approach are summarized.

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동전기 기법과 Zeolite를 이용한 중금속 오염토의 고정화에 관한 연구

  • 김종윤;김기년;김병일;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.195-198
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    • 2004
  • This study applied EK method to remediate contaminated soil by heavy metal(Pb), tried to increase the efficiency of remediation using zeolite as enhanced EK remediation method to overcome the limit of traditional EK remediation method. Adsorption tests on Pb were conducted to apply the EK extraction and test conditions which contained the electrode reversal, operating time were established. After tests, lead-ions were transported into the specific position of zeolite by EK phenomena, then the immobilization of lead-ions at zeolite was developed. Based on these tests, the efficiency of remediation is different with its test conditions. In addition, the efficiency of remediation was improved dramatically by adding zeolite without electrode reversal and satisfied TCLP regulation of EPA in USA through the whole sample range. Finally, absorption and immobilization capacity of zeolite were proved its excellence and confirmed the possibility of application as enhanced EK remediation method.

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Preparation and characteristics of inorganic membrane for air dehumidification (공기 제습용 무기막의 제조 및 특성)

  • Kim, Jeong-Eun;Kim, Byoung-Moon;Song, Kun-Ho;Chang, Wha-lk;Lee, Kwang-Rae
    • Journal of Industrial Technology
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    • v.26 no.B
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    • pp.157-162
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    • 2006
  • Recently, the humidity adjustment of indoor air is of great importance in air conditioning system as a applied, in buildings, vehicles, and containers for storage and transport of perishable products. Membrane dehumidification or air is potentially attractive because it offers low capital and operating costs, along with low energy consumption. And membrane dehumidification process attracted the attention of the public instead of the other dehumidification processes, such as adsorption, absorption, and refrigeration cycles and so on. In this study, the prepared hydrophilic inorganic membrane-based dehumidifiers(membrane air dehumidification) examined the performance of dehumidification. The surface-modified inorganic membrane prepared in this study showed high dehumidification efficiency(over 80%). The membrane might be very useful for dehumidification industries.

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Thiobacillus ferrooxidans 생물막과 화학적 방법에 의한 항화수소 처리 공정 개발

  • Jeong, Seung-Ho;Jang, Yeong-Seon;Cha, Jin-Myeong;Kim, Tae-Won;Lee, Gwang-Yeon;O, Min-Ha;Park, Don-Hui
    • 한국생물공학회:학술대회논문집
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    • 2002.04a
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    • pp.423-426
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    • 2002
  • A novel process for $H_2S$ gas treatment has been introduced, based on the combined action of a chemical absorption step and a biological step involving the biocatalytic activity of the bacterium Thiobacillus ferrooxidans. The aim of this study is the development of a process for $H_2S$ elimination from gas streams based on that chemical/biological method. The immobilized biomass reactor/chemical adsorption system is suitable for application of the removal of $H_2S$. A double stage reactor was used for the experimental work. The removal efficiencies of over 99% were observed in the range of inlet $H_2S$ concentration from 200 to 1,000ppm. The novel process showed the stable elimination efficiencies of over 95% under the retention time range from 20 to 40sec at the 1,000ppm of $H_2S$ inlet concentration.

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The Study of Curcuma Longs L. Dyeing (울금의 염색성에 관한 연구)

  • 주영주;소황옥
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.3
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    • pp.429-437
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    • 1996
  • This paper surveys extraction condition-temperature, pH, and changes of adsorbance in accordance with extraction condition of curcuma Longa L. solution. Using extracted curcuma Longa L. Solution, dyeing behaviors with natural fiber, effect of mordants to color fastness and color change were investigated. It was found that the amount of absorption (K/S value) was increased by mordants (Fe, Cr) and mordants treatment affected color change of dyed fabric. Among the mordants, effect of citric acid to color change of dyed fabric was the smallest, and color difference of post- mordant treatment is smaller than that of pee-mordant treatment in making use of citric acid as mordant. And K/S value of post mordant was higher than that of pre mordant. It was found that the pre - and post- mordants treatment little affected color fastness, but affected the amound of adsorption and color change of dyed fabric.

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Mechanical Properties of Magnesium Oxide Matrix Accroding to W/B Ratio and Adding Ratio of Vermiculite (W/B 및 버미큘라이트 첨가량에 따른 산화마그네슘 경화체의 역학적 특성)

  • Lim, Hyun-ung;Gwon, Oh-Han;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.05a
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    • pp.141-142
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    • 2016
  • This study was examine the possibility and mechanical properties to adsorption and decrease of caused interior Radon using performance superior cation-exchange to take advantage of the building. Radon absorption type Matrix using the magnesium oxide and vermiculite was experiment to product that vermiculite added Vermiculite to 10% of magnesium oxide and magnesium chloride was fixed to 25%. W/B was carried out in 45, 50, 55, 60 (wt,%).

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Interaction of SO2 with Oxygen on Ni(100) Studied by XPS and NEXAFS

  • Kim, Chang-Min
    • Bulletin of the Korean Chemical Society
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    • v.27 no.12
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    • pp.2037-2039
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    • 2006
  • The adsorption and surface reactions of $SO_2$ on Ni(100), c($2{\times}2$)_O/Ni (100) and NiO(111)/Ni(100) surfaces have been investigated using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) technique. On Ni(100), chemisorbed $SO_2$ is formed at 160 K. When $SO_2$ is adsorbed on c($2{\times}2$)_O/Ni(100) at 160 K, $SO_2$ reacts with oxygen to form $SO_3$ and trace amount of $SO_4$ species. $SO_3$ is adsorbed on this surface with its $C_3$ axis perpendicular to the surface. On a NiO(111)/Ni(100) surface, both $SO_3$ and $SO_4$ species are formed at 160 K from adsorbed $SO_2$.

The Surface Analysis of the Merocyanine Dye LB film using Optical system (광학시스템을 이용한 메로시아닌 색소 LB막의 표면 모폴로지 해석)

  • Kang, Ki-Ho;Shin, Hoon-Kyu;Chang, Jung-Soo;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1714-1716
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    • 2000
  • We fabricated the optical system of merocyanine dye using Langmuir-Blodgett(LB) technique because quite uniform orientation could be obtained, which is one of the most important factors to affect to its optical characteristics. The resonance frequency and other electrical parameters at the parallel resonance state were measured using the impedance analyser(HP 4294 A). Also the morphological changes of dye molecules after UV irradiation were observed using AFM. The parallel resonance frequency and resistance by electrical equivalent circuit were decreased with the UV irradiation and these aspects are different from general mass adsorption process. Therefore the structural changes of dye molecules are being considered, that is, the aggregated molecules become dissociated. It indicates that the shifts of the resonance frequency and the others occurred without mass absorption.

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Performance Evaluation of Water Vapour Adsorption & Desorption Properties of Low-Priced Generic Ceramic Panel Materials for Humidity Control - Focuses on analyzed measurements of temperature and humidity obtained from the housing units - (저가보급형 습도조절용 세라믹패널의 조습성능 평가 - 리빙랩 온·습도 모니터링 분석을 통한 실측결과를 중심으로 -)

  • Jang, Kun-Young;Ryu, Dong-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.11a
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    • pp.39-40
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    • 2017
  • This study aims to evaluate the humidity control performance of low-priced generic ceramic panels that are used to control humidity. Temperature and humidity are monitored by using 'Living Lab' and the change of indoor relative humidity is measured and analyzed. According to the results of the study, the indoor relative humidity of rooms installed with ceramic panels was found to be low compared to that of living rooms by 2.2%RH (test period) and 3.2%RH (daily). In the case of maximum relative humidity, rooms installed with ceramic panels were found to be low by 6.9%RH. The results are attributable to the humidity absorption of ceramic panels. Accordingly, future ceramic panels need the improvement of performance and an appropriate construction area should be derived depending on indoor space.

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