• Title/Summary/Keyword: PM adsorption

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Assessment of the Particulate Matter Reduction Potential of Climbing Plants on Green Walls for Air Quality Management

  • Jeong, Na Ra;Kim, Jeong-Hee;Han, Seung Won;Kim, Jong-Cheol;Kim, Woo Young
    • Journal of People, Plants, and Environment
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    • v.24 no.4
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    • pp.377-387
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    • 2021
  • Background and objective: To improve air quality, particulate matter (PM) can be reduced using green infrastructure. Therefore, in this study, we aimed to determine the particulate matter reduction potential of climbing plants used for green walls, an element of vertical green infrastructure. Methods: A sealed chamber with controlled environmental variables was used to assess the PM reduction level caused by climbing plants. PM concentration in the plant chamber was measured after two and four hours of PM exposure, and the reduction potential was assessed based on the leaf area. Results: Compared to the empty chamber (Control), the PM reduction speed per hour was higher in the plant chamber, which confirmed that climbing plants contribute to the reduction of PM in the air. The PM reduction speed immediately after exposure in the plant chamber was high, but this slowed over time. Additionally, PM has been continuously reduced in plants with large leaves. As a result of calculating the particulate matter reduction level based on leaf area, it was found that there was a difference by particle size. Actinidia arguta, Parthenocissus tricuspidata, Trachelospermum asiaticum, and Euonymus fortunei var. radicans showed a high reduction effect. The trichomes on the leaf surface of Trachelospermum asiaticum were found to affect PM reduction. Conclusion: PM adsorption on the leaf surface is an important factor in reducing its concentration. It was possible to compare different plants by quantifying the amount of PM reduction during a fixed time period. These results can be used as the basic data to select the plant species suitable for urban green walls in terms of PM reduction.

Cadmium Uptake by Mon-viable Biomass from a Marine Brown Alga Ecklonia radiata Turn.

  • Park, Eun-Kee;Lee, Sung-Eun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.7 no.4
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    • pp.221-224
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    • 2002
  • Biomass of non-viable and dried brown marine algae Ecklonia radiata Turn. was used to examine Its cadmium uptake capability. Twelve different pretreatments on the algal biomass were prepared. Among these pretreatments, the algal biomass, which treated with 0.1 M NaOH and kept in water. bath (100$\^{C}$, 18 h) followed by washing with distilled water and squeezing, showed the highest amount of cadmium uptake as 1634 $\pm$ 195 mg/g dry biomass at pH 4.0 and 50$\^{C}$. Adsorption temperatures and pH levels played some Important role In cadmium uptake. However, cadmium uptake decreased dramatically at a lower pH than 4.0. Freundlich adsorption isotherm showed potent cadmium uptake capacity of the non-viable biomass. Pretreatments on the non-viable algal biomass shown in this study nay enhance the Eadmium removal in the industrial wastewater.

Precursor and Substituent Effects on the Alternate Adsorption of Polycation and Anionic Dyes as Studied by Second Harmonic Generation and Absorption Spectroscopies

  • Yamada, Sunao;Niidome, Yasuro;Hinoguchi, Takeshi
    • Journal of Photoscience
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    • v.7 no.1
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    • pp.9-13
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    • 2000
  • An alternately assembled polycation-anionic dye film was prepared on a precursor assembly of poly(allylamine)hydrochloride (PAH) and poly(sodium styrenesulfonate) (PSS) or of poly (djallyldimethyl)ammonium chloride (PDDA) and PSS. The (PAH/PSS) precursor assembly gave better adsorptivity to the anionic dye than the (PDDA/PSS) one. Four kinds of anionic dyes (EB-T, AR-17 AR-18, AR-27) with different numbers of sulfonate substituents were compared. The extent of dye assembling was higher for the dye with a smaller number of sufonate substituents. Second harmonic generation (SHG) was clearly observed from the films. The SHG signal and the absorption intensity correlated well up to four polycation/dye bilayers, while further assembly did not increase the SHG signal appreciably. Second order nonlinear coefficients for ten bilayer assemblies were the order of pm/V.

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Initial growth mode of ultra-thin Al films on a W(110) surface at high temperatures

  • Choi, Dae Sun;Park, Mi Mi
    • Applied Science and Convergence Technology
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    • v.24 no.6
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    • pp.228-231
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    • 2015
  • We investigated the adsorption structures and the initial growth mode of ultra-thin Al films on a W(110) surface at a high temperature. When Al atoms were adsorbed on the W(110) at the substrate temperature of 1100 K and with coverage of 0.5ML, Al atoms formed a p($2{\times}1$) double-domain structure. When the coverage was 1.0 ML, the double domain of a hexagonal structure (fcc(111) face) rotated ${\pm}5^{\circ}$ from the [100] direction of the W(110) surface and another distorted hexagonal structure were found. Low-energy electron diffraction results along with ion scattering spectroscopy results showed that the Al atoms followed the Volmer-Weber growth mode at a high temperature.

Chemisorption and orientation of Selenopheneon Si(100)-$2{\times}1$

  • Lee, Han-Koo;Kim, Ki-Jeong;Kim, Hyeong-Do;Shin, Hyun-Joon;Kim, Bong-Soo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.372-372
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    • 2010
  • We have investigated adsorption of selenophene on Si(100) at room temperature using high resolution photoemission spectroscopy (HRPES) and near edge X-ray absorption fine structure (NEXAFS) in the partial electron yield (PEY) mode. The Si 2p, C 1s, Se 3d spectra of selenophene on Si(100) show that selenophene is nondissociatively chemisorbed on Si(100)-$2{\times}1$ through [2+2] cycloaddition. NEXAFS has been conducted to characterize the adsorption geometry of selenophene on Si(100). Since the $\pi^*$ orbital of C=C bond show good angular dependence in carbon K-edge NEXAFS spectra, the angle $53{\pm}5^{\circ}$ determined from NEXAFS spectra. This majority structure is consistent with the [2+2] cycloaddition of selenophene to the dimer of the Si(100)-$2{\times}1$ surface.

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Comparison of the effect of peat moss and zeolite on ammonia volatilization as a source of fine particulate matter (PM 2.5) from upland soil

  • Park, Seong Min;Hong, Chang Oh
    • Korean Journal of Agricultural Science
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    • v.46 no.4
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    • pp.907-914
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    • 2019
  • Ammonia (NH3) that reacts with nitric or sulfuric acid in the air is the major culprit contributing to the formation of fine particulate matter (PM2.5). NH3 volatilization mainly originates from nitrogen fertilizer and livestock manure applied to arable soil. Cation exchange capacity (CEC) of peat moss (PM) and zeolite (ZL) is high enough to adsorb ammonium (NH4+) in soil. Therefore, they might inhibit volatilization of NH3. The objective of this study was to compare the effect of PM and ZL on NH3 volatilization from upland soil. For this, a laboratory experiment was carried out, and NH3 volatilization from the soil was monitored for 12 days. PM and ZL were added at the rate of 0, 1, 2, and 4% (wt wt-1) with 354 N g m-2 of urea. Cumulative NH3-N volatilization decreased with increasing addition rate of both materials. Mean value of cumulative NH3-N volatilization across application rate with PM was lower than that with ZL. CEC increased with increasing addition rate of both materials. While the soil pH increased with ZL, it decreased with PM. Increase in CEC resulted in NH4+ adsorption on the negative charge of the external surface of both materials. In addition, decrease in soil pH hinders the conversion of NH4+ to NH3. Based on the above results, the addition of PM or ZL could be an optimum management to reduce NH3 volatilization from the soil. However, PM was more effective in decreasing NH3 volatilization than ZL due to the combined effect of CEC and pH.

Adsorption and Leaching of cis and frans-Permethrin in the Soil (토양 중 cis 및 trans-Permethrin의 흡착 및 침출)

  • Sam Edward Feagley
    • Journal of Environmental Science International
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    • v.4 no.4
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    • pp.379-386
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    • 1995
  • Permethrin [3-phenox yben zyl(1RS)-cis,tans-3-(2,2-dichloroviny1)-2,2- dimethylcyclopropane carboxylate] insecticides were selected to study adsorption and leaching potentials related to pollution on Commerce silty clay loam soil near Baton Rouge, Louisiana, USA. GLC-ECD chromatogram of permethrin included 32.5 % of cis-pemehin and 67.4 % of trans-permethrin. Extraction efficiencies of is and trmu-pemetun were 92.5 % and 92.3 % in fortified water, respectively and 85.9 % and 88.8 % in fortified soil, respectively. At a 1:10 moi]/water ratio,the Koc values for sis and fan isomers of permethrin were 938 and 877, respectively. Leaching of permethrin was evaluated in soil columns$(5.4 cm i.d. \times 26 cm length)$. Total recoveries of the permethrin applied to the soil column were $84.5\pm3.1%$. When the soil columns were leached with three pore volumes of water, the distributions of cis-permethrin leached were 6.10 % and 0.07 % of amount applied in the untreated zone soil and leachate water, respectively Trans-pemethrin distributions were 5.20 % in the untreated zone soil and 0.05 % in leachate water. Cis and trans-pemethrin was strongly adsorbed to soil. The results of the study showed the strong relationship between adsorption and leaching. Cis and trans-permethrin to be leached into the groundwater in soils with shallow aquifers were suggested a low leaching potential.

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Thermodynamic Properties of Kr Gas Adsorbed on Graphite Surface (흑연 표면에 흡착된 Kr 기체의 열역학적 성질)

  • Woon-Sun Ahn;Kyung Hee Ham;Eun Ah Yoo;Kwang Soon Lee
    • Journal of the Korean Chemical Society
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    • v.26 no.4
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    • pp.211-217
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    • 1982
  • Assuming krypton molecules adsorbed on the graphite surface as a two-dimensional (2D) gas, 4th virial coefficient of the virial equation is calculated by the use of cluster integrals. The Henry's law constant, and 2nd and 3rd virial coefficients are also calculated. Adsorption isotherms calculated from this virial equation agree very satisfactorily with experimental results. The interaction energy of Kr-graphite surface is calculated assuming the pairwise additivity of Lennard-Jones(12,6) potential, and parametars therein are taken as; ${\varepsilon}_{gs}$/k = 71.1 K, ${\varepsilon}_{gg}$/k = 170 K, ${\sigma}_{gs}$ = 354 pm, and ${\sigma}_{gg}$ = 368 pm.

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Studies on sterile filters in the preparation of N-13 ammonia injection (N-13 암모니아 주사액 제조 시 멸균필터의 흡착율 차이에 관한 비교 평가)

  • Oh, Chang Bum;Kim, Si Hwal;Cha, Min Jung;Shin, Jin;Ji, Yong Gi;Choi, Sung Ook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.23 no.1
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    • pp.64-68
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    • 2019
  • Purpose In the preparation process for N-13 Ammonia injections, there were radioactive medicines adsorbed on filters remarkably. Hereby, we have compared the adsorption rate and quality test on Millex GS filter and Satorious Minisart filter, both representatively hydrophilic sterilizing filters, also evaluated which filter is more accommodative for N-13 Ammonia injection. Materials and Methods The filters used for sterilization of N-13 Ammonia injections were Millex GS filter($0.22{\mu}m$) mand Satorious Minisart filter ($0.2{\mu}m$), which are generally used to strain aqueous solutions. After the N-13 Ammonia passes through each sterilization filter, the adsorption rate of the filter (n=10) is determined by measuring not only the radioactivity through the filter also the amount of radioactivity remaining in it using a Dose Calibrator. The N-13 Ammonia injections after each filter is tested by the quality control test to conform to the Samsung Medical Center standard. Results The ratio of radioactivity passed through Millex GS indicated $29.0{\pm}17.6%$. Satorious Minisart filters output was $80.9{\pm}3.2%$, respectively. Each ratio of radioactivity adsorbed on the sterile filter was $71.0{\pm}17.6%$ for Millex GS and $19.1{\pm}3.2%$ for the Satorious Minisart filters, respectively. Furthermore, on the ratio of filtered radioactivity, Using Satorious Minisart filter showed about 2.8 times higher than using Millex GS filter. The quality testing of N-13 Ammonia injections through each filter met the Samsung Medical Center standard. Conclusion The Millex GS filter is composed of cellulose acetate and cellulose nitrate, whereas the Satorious Minisart filter if composed only of cellulose acetate. Therefore, the presence of cellulose nitrate in the membrane seems to have made differences. Therefore, the use of Satorious Minisart filter in the preparation of N-13 Ammonia injection solution minimized the loss of radioactive medicines due to filter adsorption, thereby improving the synthesis yield.

Characterization and Electron Microscopic Visualization of the Plasmid and the Gene Expression in the Escherichia coli (E. coli의 유전자 발현 및 플라스미드 DNA 구조의 특성에 관한 연구)

  • Kim, Sung-Jun;Park, Yeal;Lee, Sook-Young;Kim, Hong-Seob;Kim, Woo-Kap
    • Applied Microscopy
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    • v.20 no.2
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    • pp.57-70
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    • 1990
  • Characterization and electron microscopic visualization of the plasmid and the gene expression of Escherichia coli were carried out. Transcriptional units of active structural genes were observed after lysis of Escherichia coli cells. The ribosomes attached to the E. coli genome on mRNA molecule as polyribosomes. From this gradient of polyribosome length, we estimated location of mRNA synthesis initiation site. In this experiment, a granule is ofen present which may correspond to a RNA polymerase at the promoter site. pOX1, pOX7, pOX7A, $pOX7{\Delta}1$, pSTP36, pSTP21, pBR322, and pJH12 were visualized by way of electron microscope, and their estimated sizes were determined to be $5.70{\pm}0.08{\mu}m,\;2.15{\pm}0.10{\mu}m,\;2.14{\pm}0.12{\mu}m,\;7.39{\pm}0.08{\mu}m,\;4.03{\pm}0.04{\mu}m,\;1.50{\pm}0.03{\mu}m\;and\;1.25{\pm}0.09{\mu}m$ respectively. One micrometer of measured length corresponded to about 3.0 Kb. Mica-press adsorption method that allows selectivs visualization of the plasmid DNA released in situ from the bacterial cell is rapid and useful for visualization of plasmids. The released plasmid DNA was adsorbed preferently on mica in a divalent cation-free solution. Miller chromatin-spreading method was useful to observe the plasmid and transcripts. BAC method and cytochrome C monolayer were useful to observe the plasmid DNA. Our ability to visualize ultrastructural aspects of the expression of E. coli has given us a unique tool with which to study the regulation the level of an individual gene.

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