• Title/Summary/Keyword: anion

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Anion Distribution and Correlation Analysis by Fountain Type in Urban (도심지내 분수유형별 음이온 분포 및 상관성 분석)

  • Kim, Jeong-Ho;Park, Seung-Hwan;Kim, Won-Tae;Yoon, Yong-Han
    • Journal of Environmental Science International
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    • v.22 no.12
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    • pp.1599-1610
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    • 2013
  • In order to verify the healing effect in the variety of effects according to fountain type, anion which is the representatives factor of healing, as the center of case studies which in Gwanghwamun(Ground fountain), Cheonggyecheon(Waterfall) and Myeongdong(Formative fountain). According to fountain type, the anion distribution as follow, figures typically$ 15,721{\pm}419ea/cm^3$, Formative fountain $40,190{\pm}788ea/cm^3$, Waterfall $4.480{\pm}290ea/cm^3$ and ground fountain $2.492{\pm}180ea/cm^3$. It is usually exceed to the distribution in natural green, which is $1070{\sim}2100ea/cm^3$. The interrelation between air temperature, relative humidity, wind speed and relative humidity, and wind speed is that, the relative humidity is directly proportional to wind speed and inversely proportional to temperature. As the temperature goes up, the distribution of anion goes down. And as the wind speed and relative humidity goes up, the distribution of anion decrease sharply. The result of interrelation between fountain type and the anion distribution is that, the distance of water falling is directly proportional to the anion distribution in the formative fountain and inversely proportional in the ground fountain. And the distribution of anion is largest in formative fountain. The distribution of anion in ground fountain is lower than in formative fountain, but it is far more than in natural greenery. And as the distance from fountain increase, the distribution of anion goes down.

Preparation of an Anion Exchange Membrane Using the Blending Polymer of Poly(ether sulfone) (PES) and Poly(phenylene sulfide sulfone) (PPSS) (폴리에테르설폰-폴리페닐렌설파이드설폰 블렌딩 고분자를 이용한 음이온교환막의 제조)

  • Lee, Kyung-Han;Han, Joo-Young;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.29 no.3
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    • pp.155-163
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    • 2019
  • The anion exchange membrane using the blending polymer of poly(ether sulfone) and poly(phenylene sulfide sulfone) was prepared. It was confirmed by EDXS and FT-IR analysis that the prepared anion exchange membrane had the -N- as an anion exchange group. The ionic conductivity in 1 mol/L $H_2SO_4$ aqueous solution was measured. The ionic conductivity of the prepared anion exchange membrane was 0.015~0.083 S/cm, and had a high value compared with AFN and APS as a commercial anion exchange membrane. Permeabilities of the vanadium ions through the prepared anion exchange membrane were tested to evaluate the possibility as a separator in vanadium redox flow battery. Vanadium ion permeation rate in the prepared anion exchange membrane had a low value compared with Nafion 117 as a commercial cation exchange and AFN as a commercial anion exchange membrane.

Correlations Between Concentrations of Negative Ions and Forest Type, and Site Factors at National Forests in Yangyang-gun (양양군 국유림 지역의 음이온 농도와 임상, 숲 관련인자와의 상관)

  • Um, Tae-Won;Kim, Gab-Tae
    • Korean Journal of Environment and Ecology
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    • v.24 no.5
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    • pp.539-546
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    • 2010
  • To investigate the variation of anion concentrations in relation to forest type, forest-related factors, forest survey and anion concentrations measurement were carried out on the 52 quadrats located at the national forest areas in Yangyang-gun, Kangwon-do. The relationship between anion concentrations and forest-related factors were correlated. Total mean of anion concentration was 2,405 ea/$cm^3$, which was slightly higher than general figures 2,000ea/$cm^3$. Highly significant positive correlations were observed between anion concentrations and soil moisture contents, and also between anion concentrations and altitude. Significant positive correlations were observed between anion concentrations and topography. Anion concentrations were significantly different among soil moisture levels. Mean anion concentration were highest at 4,524.4ea/$cm^3$ in on wet sites, and followed slightly wet sites and moderate sites. Mean anion concentrations was highest on valley sites at 3,372.4ea/$cm^3$, followed by slope and ridge areas. Mean anion concentrations measured before noon was highest at 3,133.4ea/$cm^3$, and measurements during 12:00~15:00 and after 15:00, showed relatively low anion concentrations. Mean anion concentrations was highest at mixed deciduous forests at 3,503.9ea/$cm^3$, followed by oak forests, pine forests, and pine-oak forests. Results of this study are expected to be used in planning therapeutic forests.

An Experimental Study on the Compressive Strength and Chloride ion penetration resistance of Cement Mortar mixing Anion Exchange Resin (음이온교환수지 혼입 시멘트 모르타르의 압축강도 및 염소이온 침투 저항성에 관한 실험적 연구)

  • Jung, Do-Hyun;Lee, Yun-Su;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.23-24
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    • 2018
  • Reinforced concrete is a building material that is generally used in modern society. Also, reinforced concrete structures in high salinity environments have low durability due to corrosion of reinforcing bars due to infiltrated chlorine ions. Anion exchange resins have an ability to immobilize chlorine ions in the resin while releasing their anions. As a material, it has already been shown that it is possible to fix the chloride ion inside the cementitious material through the cement mortar experiment. The purpose of this study is to confirm the compressive strength of cement mortar using powdered anion exchange resin after powdering an anion exchange resin. In order to confirm the chloride ion fixation ability of the powder anion exchange resin, chlorine ion penetration resistance test was carried out.

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Influence of Quaternary Ammonium Anion Exchange Moieties onto Mechanical Properties of Radiation-grafting Anion Exchange Membranes (방사선그라프팅 음이온교환막의 기계적 물성에 대한 4차 암모늄 음이온교환기의 영향)

  • Ko, Beom-Seok;Sohn, Joon-Yong;Shin, Junhwa
    • Journal of Radiation Industry
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    • v.6 no.1
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    • pp.49-54
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    • 2012
  • Various anion exchange membranes were prepared by radiation graft copolymerization of vinylbenzyl chloride onto fluorinated films and subsequent quaternization with various tertiary amines such as trimethylamine, N,N-dimethylbuthylamine, N,N-dimethylaniline, and N-methylpiperidine. The quaternizations of the anion exchange membranes were confirmed by measuring of the ion exchange capacities of the membranes. The mechanical properties and the water uptakes were also measured. The elongation at break was found to be largely dependent on the fluorinated film, the quateranry ammonium, and the degree of grafting. The results indicate that the poly (ethylene-alt-tetrafluoroethylene) with quaternized trimethylamine moiety exhibits higher flexible property compared to the other prepared anion exchange membranes.

Adsorption of Selenium in Industrial Wastewater Using Anion Exchange Resin and Activated Carbon (음이온교환수지와 활성탄을 이용한 산업 폐수 중 셀레늄의 흡착)

  • Han, Sang-Uk;Park, Jin-Do;Lee, Hak-Sung
    • Journal of Environmental Science International
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    • v.18 no.12
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    • pp.1411-1416
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    • 2009
  • Several adsorbents were tried to remove the selenium ions from industrial wastewater and the following ascending order of the adsorption performance for the selenium at pH 9 was observed: cation exchange resin < chelate resin < zeolite < brown marine algae < granular activated carbon < anion exchange resin. Initial concentration of selenium(146 mg/L) in industrial wastewater was reduced to 63 mg/L of selenium at pH 9 by neutralization process. The maximum uptake of Se calculated from the Langmuir isotherm with anion exchange resin was 0.091 mmol/g at pH 10 and that with granular activated carbon was 0.083 mmol/g at pH 6. The affinity coefficients of Se ion towards anion exchange resin and granular activated carbon were 3.263 L/mmol at pH 10 and 0.873 L/mmol at pH 6, respectively. The sorption performance of anion exchange resin at the low concentration of Se, namely, was much better than that of granular activated carbon. The Se ions from industrial wastewater throughout neutralization process and two steps of adsorption using anion exchange resin was removed to 97.7%.

Durability enhancement of anion exchange membranes for water electrolysis: an updated review

  • Akter, Mahamuda;Park, Jong-Hyeok;Kim, Beom-Seok;Lee, Minyoung;Jeong, Dahye;Shin, Jiyun;Park, Jin-Soo
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.319-327
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    • 2022
  • Ion exchange membranes have been developed from laboratory tools to industrial products with significant technical and trade impacts in the last 70 years. Today, ion exchange membranes are successfully applied for water and energy for different electro-membrane processes. Hydrogen could be produced by electrochemical water splitting using renewable energy, for example, solar, biomass, geothermal and wind energy. This review briefly summarizes the recent studies reporting the state-of-the-art anion-exchange membrane water electrolysis, especially focusing on the enhancement of the durability of anion-exchange membranes. Anion-exchange membrane water electrolysis could be used as inexpensive non-noble metal electrocatalysts that are capable of producing low cost of hydrogen. However, the main challenge of anion-exchange membrane water electrolysis is to increase the performance and durability. In this mini review, the limiting factors of the durability and the technology enhancing the durability will be discussed for anion exchange membrane water electrolysis.

Anion Receptors with 2-Imidazolidone Molecular Scaffold

  • Kim, Hyung-Il;Kang, Jong-Min
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1531-1534
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    • 2007
  • Anion receptor based on 2-imidazolidone molecular scaffold has been synthesized. Anion binding studies carried out using 1H NMR and UV?vis spectroscopy revealed that this receptor 6 displays selectivity for the for the oxyanions such as acetate and dihydrogenphosphate ions and the affinity for the anions simply reflects the basicity of anions.

Study on the Preparation of Polyvinyl Chloride Anion Exchange Membrane as a Separator in the Alkaline Water Electrolysis (알칼리 수전해용 격막으로서 폴리염화비닐(polyvinyl chloride) 음이온교환막의 제조에 관한 연구)

  • Park, Jong-Ho;Bong, Soo-Yeon;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.23 no.6
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    • pp.469-474
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    • 2013
  • An anion exchange membrane was prepared for a separator in the alkaline water electrolysis. An anion exchange membrane was prepared by the chloromethylation and amination of polyvinyl chloride (PVC) used as a base polymer. The membrane properties of the prepared anion exchange membrane such as the membrane resistance and ion exchange capacity were measured. The minimum membrane resistance of the prepared anion exchange membrane was $2.9{\Omega}{\cdot}cm^2$ in 1M NaOH aq. solution. This membrane had 2.17 meq./g-dry-membrane and 43.4% for the ion exchange capacity and water content, respectively. The membrane properties of the prepared anion exchange membrane was compared with that of the commercial anion exchange membrane. The membrane resistance decreased in the order; AHT>IOMAC> Homemade membrane> AHA>APS=AFN. The ion exchange capacity decreased in the order; Homemade membrane>AFN>APS>AHT>AHA>IOMAC.