• Title/Summary/Keyword: Fe-Cr

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The Effect of Aircraft Traffic Emissions on the Soil Surface Contamination Analysis around the International Airport in Delhi, India

  • Ray, Sharmila;Khillare, P.S.;Kim, Ki-Hyun
    • Asian Journal of Atmospheric Environment
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    • v.6 no.2
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    • pp.118-126
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    • 2012
  • To investigate the effect of aircraft traffic emissions on soil pollution, metal levels were analyzed for 8 metals (Fe, Cr, Pb, Zn, Cu, Ni, Mn and Cd) from the vicinity of the Indira Gandhi International (IGI) airport in Delhi, India. The texture of the airport soil was observed to be sandy. Among the metals, Cd showed minimum concentration ($2.07{\mu}g\;g^{-1}$), while Fe showed maximum concentration ($4379{\mu}g\;g^{-1}$). The highest metal accumulation was observed at the landing site. Significant correlations were observed between metals and different textures (sand, silt, and clay) as well as with organic carbon (OC). The results indicate that grain size play a major role in OC retention in soil and subsequently helps in adsorption of metals in soil. M$\ddot{u}$ller's geoaccumulation index (I-geo) showed that airport soil was contaminated due to Cd and Pb with the pollution class 2 and 1, respectively. Pollution load index of the airport site was 1.34-3 times higher than the background site. The results of factor analysis suggested that source of the soil metal is mainly from natural weathering of soil, aircraft exhaust, and automobile exhaust from near by area. With respect to Dutch target values, the airport soils showed ~3 times higher Cd concentration. The study highlighted the future risk of enhanced metal pollution with respect to Cd and Pb due to aircraft trafficking.

Synthetic, Characterization, Biological, Electrical and Catalytic Studies of Some Transition Metal Complexes of Unsymmetrical Quadridentate Schiff Base Ligand

  • Maldhure, A. K.;Pethe, G. B.;Yaul, A. R.;Aswar, A. S.
    • Journal of the Korean Chemical Society
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    • v.59 no.3
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    • pp.215-224
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    • 2015
  • Unsymmetrical tetradentate Schiff base N-(2-hydroxy-5-methylacetophenone)-N'-(2-hydroxy acetophenone) ethylene diamine (H2L) and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, IR, electronic spectra and thermogravimetric analyses. 1H, 13C-NMR and FAB Mass spectra of ligand clearly indicate the presence of OH and azomethine groups. Elemental analyses of the complexes indicate that the metal to ligand ratio is 1:1 in all complexes. Infrared spectra of complexes indicate a dibasic quadridentate nature of the ligand and its coordination to metal ions through phenolic oxygen and azomethine nitrogen atoms. The thermal behavior of these complexes showed the loss of lattice water in the first step followed by decomposition of the ligand in subsequent steps. The thermal data have also been analyzed for the kinetic parameters by using Horowitz-Metzger method. The dependence of the electrical conductivity on the temperature has been studied over the temperature range 313-403 K and the complexes are found to show semiconducting behavior. XRD and SEM images of some representative complexes have been recorded. The antimicrobial activity of the ligand and its complexes has been screened against various microorganisms and all of them were found to be active against the test organisms. The Fe(III) and Ni(II) complex have been tested for the catalytic oxidation of styrene.

The Study on Natural Dyeability of Aloe Vera Extract (알로에 베라 추출물의 천연염색성에 관한 연구)

  • 박영득;김정화
    • Journal of the Korea Fashion and Costume Design Association
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    • v.4 no.1
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    • pp.73-84
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    • 2002
  • The purpose of this study was to investigate the natural dyeability on extract of Aloe Vera princeps. The experimental items were divided into the mordanting method, component of fabric, extracting portion, and kind of mordants. The experimental study was done to by laundering, abrasion(dry/wet), perspiration(acid/alkali), light fastness test and color difference by C.C.M system. The summerized finding resulted from experiments and investigation are suggested as follows: First, in the C.C.M test on mordanting method, color difference was significantly improved when mordants were treatmented. And the premordanting method showed the highest color difference. Second, in the C.C.M test on component of fabric, color difference of silk was higher than cotton. It was considered that silk has -$\NH_2$, -COOH, -OH more than cotton. Third, in the C.C.M Test on extracting portion, color difference of extracting in skin of Aloe leaf was three times higher than that of inside lump. Forth, in dyeing-fastness on mordants, laundering fastness showed 3 ~ 4 grade nearly. In perspiration-fastness(acid/alkali), Al(4~5/4~5) was the highest. In abrasion-fastness(dry/wet), cotton(4~5/4~5) was higher than silk (4~5/4) in all mordants. In light-fastness, silk(2~5) was higher than cotton(1~2) generally and especially Cu mordant of silk(4~5) was the highest. Sixth, in color difference analysis on 7 mordants Cu(29.9), Fe(28.7) and Cr(28.9) showed the highest in silk. And Cu(12.7), Fe(10.42) and Sn(10.43) showed the highest in cotton and Al(23.6, 8.0) showed the lowest in silk and cotton.

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A Comparison Study on the Concentration of Total Welding Fume and Respirable Particulate Mass for Welding Workers of a Shipbuilding (조선소 용접작업자들의 총용접흄과 호흡성분진농도 비교연구)

  • Kang, Yong-Seon;Sim, Sang-Hyo;Lee, Song-Kwon;Bin, Sung-Oh;Choi, Eun-Seok
    • Journal of Environmental Health Sciences
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    • v.33 no.4
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    • pp.276-282
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    • 2007
  • The purpose of this study is to assess the accurate state of the following: total welding fumes versus welding fumes in the air, respirable particulate mass, and exposure of dockyard welders to heavy metals. In addition, this study provides basic data for proposing improvements to create efficient and appropriate welding environments and to prevent occupational diseases. The subjects of this study were 94 laborers who worked at the block construction sites of large-scale dockyards located in Gyeongnam Province from March 2005 to June 2005. In order to collect samples on total welding fumes in the air and respirable particulate mass from the welders, Methods 0500 and 0600, established by the National Institute for Occupational Safety and Health (NIOSH), were used. The metals within the welding fumes were also analyzed using Inductively Coupled Plasma (ICP) under Method 7300 from NIOSH. The results of this research are summarized below. The geometric mean concentration of total welding fumes and that of respirable particulate mass were $4.11\;mg/m^3\;and\;3.53\;mg/m^3$, respectively. As a result of comparing the two measurement methods, there were significant differences (p<0.05) between the two groups for Ca, Cu, Cr, and Ni; however, there were no differences in Fe, Mg, Zn, Mg, Pb, and Cd. As a result of the analysis, the correlation between Mn and the concentration of heavy metals in the total welding fumes and respirable particulate mass was found to be -0.29, a significant negative correlation. The correlation between other heavy metals, however, was low. Finally, in the same total welding fumes, the correlation of Fe and Mg was high.

Detection of Heavy Metal Ions in Aqueous Solution Using Direct Dye Chemosensors

  • Heo, Eun-Yeong;Ko, Young-Il;Bae, Jin-Seok
    • Textile Coloration and Finishing
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    • v.21 no.5
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    • pp.51-57
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    • 2009
  • Since heavy metal pollution is a significant global environmental problem and very dangerous to human health, the improved methods for detecting heavy metals are required recently. Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environment monitoring. New direct dyes having the function of colorimetric chemosensors were synthesized. When metal ions such as $Al^{3+}$, $Ca^{2+}$, $Cd^{2+}$, $Cr^{3+}$, $Cu^{2+}$, $Fe^{2+}$, $Fe^{3+}$, $Hg^{2+}$, $Li^+$, $Mg^{2+}$, $Na^+$, $Ni^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ were added each solution of new direct dyes, the color of solution was changed and can be easily detected with naked eyes without expensive experimental equipment such as atomic absorption spectrometer (AAS) or inductively coupled plasma?mass spectrometer (ICP-MS). The new benzidine analogues were diazotized and reacted with couplers such as H-acid, J-acid, Chromotropic acid, Nevill-winther acid and gamma acid to synthesize new direct dyes. The structures of the new direct dyes were confirmed by high resolution mass spectrometer (FAB ionization) and evaluated with UV-Vis spectroscopy. The UV-VIS spectroscopy was measured for the dye solutions by adding various concentrations of metal ions. It was observed that the absorbance in UV-Vis spectra was changed as the heavy metal ions were added.

Impact of Dust Transported from China on Air Quality in Korea -Characteristics of PM2.5 Concentrations and Metallic Elements in Asan and Seoul, Korea

  • Yang, Won-Ho;Son, Bu-Soon;Breysse, Patrick;Chung, Tae-Woong
    • Journal of Environmental Health Sciences
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    • v.33 no.6
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    • pp.479-487
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    • 2007
  • [ $PM_{2.5}$ ], particulate matter less than 2.5 um in a diameter, can penetrate deeply into the lungs. Exposure to $PM_{2.5}$ has been associated with increased hospital visits for respiratory aliments as well as increase mortality. $PM_{2.5}$ is a byproduct of combustion processes and as such has a complex composition including a variety of metallic elements, inorganic and organic compounds as well as biogenic materials (microorganisms, proteins, etc). In this study, the average concentrations of fine particulates $PM_{2.5}$ have been measured simultaneously in Asan and Seoul, Korea, by using particulate matter portable sampler from September 2001 to August 2002. Sample collection filters were analyzed by ICP-OES to determine the concentrations of metallic elements (As, Ni, Fe, Cr, Cd, Cu, Pb, Zn, Si). Annual mean $PM_{2.5}$ concentrations in Asan and Seoul were 37.70 and $45.83\;{\mu}g/m^3$, respectively. The highest concentrations of $PM_{2.5}$ were found in spring season in both cities and the concentrations of measured metallic elements except As in Asan were higher than those in Seoul, suggesting that yellow dust in spring could affect $PM_{2.5}$ concentrations in Asan rather than Seoul. The correlation coefficients of Pb and Zn were 0.343 for Asan and 0.813 for Seoul during non-yellow dust condition, suggesting that Pb and Zn were influenced with the same sources. The correlation coefficients between Si and Fe in the fine particulate mode were 0.999 (Asan) and 0.998 (Seoul) during yellow dust condition. It was suggested that these two elements were impacted by soil-related transport from China during the yellow dust storm condition.

Application of Semi-continuous Ambient Aerosol Collection System for Elemental Analysis (대기입자의 원소성분 배출특성연구를 위한 반-연속식 입자채취시스템 적용)

  • Park, Seung-Shik;Ko, Jae-Min;Lee, Dong-Soo
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.1
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    • pp.39-51
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    • 2012
  • Aerosol slurry samples were collected in 60-min interval using Korean Semi-continuous Elements in Aerosol Sampler (KSEAS) between May 19 and June 6, 2010 at an urban site of Gwangju. The $PM_{2.5}$ samples were collected with a flow rate of 16.7 L/min and particles are grown by condensation of water vapor in a condenser maintained at ${\sim}5^{\circ}C$ after saturation by direct injection of steam. The resulting droplets are collected in a liquid slurry with a airdroplet separator. Concentrations of 16 elements (Al, Fe, Mn, Ca, K, Cu, Zn, Pb, Cd, Cr, Ti, V, Ni, Co, As, Se) in the collected slurry samples were determined off-line by ICP-MS. KSEAS sample analysis encompassed the sampling periods for which 24-hr average elemental species concentrations were calculated for comparison with those derived from 24-hr integrated filter samples. Relationship between elemental species measured by two methods indicated high correlation coefficients (r), mostly greater than r of 0.80. However, we note that concentrations of Al, K, Ca, Mn, and Fe, which are often associated with crustal elemental particles, in the KSEAS samples, were substantially lower (1.4~11 times) than those found in the typical filter-based samples. This discrepancy is probably due to difficulties in transferring insoluble dust particles to the collection vials in the KSEAS. Temporal profiles of elemental concentrations indicate that some transient events in their concentrations are observed over the sampling periods. For the elemental species studied, atmospheric concentrations during the transient events increased by factors of 4 in Mn~80 in Zn, compared to their background levels. Principle component analyses were applied to the hourly KSEAS data sets to identify sources affecting the concentrations of the metal constituents observed. In this study, we conclude that hourly measurements for particle-bound elemental constituents were extremely useful for revealing the short-term variability in their concentrations and developing insights into their sources.

Gemmological Characterization of Precious Serpentine from Booyo, Korea (부여산 귀사문석의 보석학적 특성 연구)

  • 김원사;우영균;이재열;김경수
    • Journal of the Mineralogical Society of Korea
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    • v.9 no.2
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    • pp.102-112
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    • 1996
  • The precious serpentine, referring to a rare and highly valuable gem variety of serpentine group minerals, is found to occur in serpentinite from Booyo Gren Jade Mine which is located in Oesan-myun, Booyo-gun of Chungchungnam-do. Geommological properties of the precious serpentine have been investigated by use of polarizing microscope, specific gravity balance, refractometer, hardness pencils, X-ray diffractometer, XRF, ICP-MS analyser, and infrared absorption spectroscope.The precious serpentine from Booyo is colored deep green with oily luster and semi-transparent. It is highly tough and Mohs's scale of hardness is measured to be 5-6. Specific gravity is determined to be 2.67, and a single refractive index ND=1.56 is observed by a spot method, using sodium light source. X-ray powder diffraction data is represented by the reflection lines at 7.40(100), 4.64(25), 3.68(68), 2.757(69), 2.530(49), 2.549(32), and 1.710(21${\AA}$), which compares very well with that of antigorite of serpentine group minerals. The major chemical compositions of the precious serpentine group minerals. The major chemical compositions of the precious serpentine are SiO2 42.49%, MgO 39.08%, Fe2O3 3.85%, and H2O 11.87%. Besides, trace elements such as Cr(2188), Ni(1110ppm), Co(58ppm), and Ta (108ppm) are relatively spectrum shows peaks at 3670, 1190, 1070, 980 and 610cm-1. Strong absorption at 3670cm-1 is due to OH stretching, and 1190, 1070 and 980cm-1 due to SiO stretching. The absorption 610cm-1 is formed by alteration of pre-existing ultramafic rock, namely peridotite, with an introduction of fluid with very little content of CO2, under 400$^{\circ}C$ environment. Magnetite inclusions, finely disseminated in the precious serpentine, may be a result of Fe precipitation, during serpentinization of olivine-bearing country rock.

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A Study on the Characteristics of $PM_{10}$ and Air-borne Metallic Elements Produced in the Industrial City (산업도시 대기 중$PM_{10}$의 농도 및 금속원소 성분의 특성 연구)

  • 나덕재;이병규
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.1
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    • pp.23-35
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    • 2000
  • PM10, which is below 10 ${\mu}{\textrm}{m}$ in a diameter, has a high deposition in the lung or the bronchus by breathing and is generally composed of a lot of organic matters, viruses, algae, mold, and metallic elements that are very toxic to people. This study identified the characteristics of concentration of PM10 and air-borne jmetallic elements produced in the industrial city, Ulsan, and analyzed the correlatuion between sources and generation patterns of PM10 and metallic elements. We classified the five areas(green, residential, heavy traffic, mechanic, and petrochemcal and non-ferrous metal) which might have different characteristics of sources of PM10 and metallic elements. The average concentrations of PM10 in the five areas were as follows(petrochemical and non-ferrous metal(99.9$\mu\textrm{g}$/㎥)>mechanic(77.5 $\mu\textrm{g}$/㎥)>heavy traffic(47.1 $\mu\textrm{g}$/㎥)>residential(39.3 $\mu\textrm{g}$/㎥)>green(32.8 $\mu\textrm{g}$/㎥)). Those of petrochemical and non-ferrous metal areas were higher than other areas. In this study, the average concentration trend of metallic elements contained in PM10 are shown as follows: Fe>Zn>Pb>Cu>Mn>Cr>As>Cd>Sn>Hg, respectively. The metallic elements identified in PM10 showed the highest concentration in the petrochemical and non-ferrous areas. Metal combinations showed that a high correlation among concentrations of heavy metals were as follows: As, Cd and Fe in the residential area; Zn, Mn, Cu and Pb in the mechanical area; and Zn, Cu, As, Pb in the petrochemical and non-ferrous industrial area.

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Effects of V and C additions on the Thermal Expansion and Tensile Properties of a High Strength Invar Base Alloy (고강도 인바계 합금의 열팽창 및 인장 특성에 미치는 바나듐과 탄소 원소 첨가 영향)

  • Yun, A.C.;Yun, S.C.;Ha, T.K.;Song, J.H.;Lee, K.A.
    • Transactions of Materials Processing
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    • v.24 no.1
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    • pp.44-51
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    • 2015
  • The current study seeks to examine the effects of V and C additions on the mechanical and low thermal expansion properties of a high strength invar base alloy. The base alloy (Fe-36%Ni-0.9%Co-2.75%Mo-0.7Cr-0.23Mn-0.17Si-0.3%C, wt.%) contains $Mo_2C$ carbides, which form as the main precipitate. In contrast, alloys with additions of 0.4%V+0.3%C (alloy A) or 0.4%V+0.45%C (alloy B) contain $Mo_2C$+[V, Mo]C carbides. The average thermal expansion coefficients of these high strength invar based alloys were measured in the range of $5.16{\sim}5.43{\mu}m/m{\cdot}^{\circ}C$ for temperatures of $15{\sim}230^{\circ}C$. Moreover, alloy B showed lower thermal expansion coefficient than the other alloys in this temperature range. For the mechanical properties, the [V, Mo]C improved hardness and strengths(Y.S. and T.S.) of the high strength invar base alloy. T.S.(tensile strength) and Y.S.(yield strength) of hot forged alloy B specimen were measured at 844.6MPa and 518.0MPa, respectively. The tensile fractography of alloy B exhibited a ductile transgranular fracture mode and voids were initiated between the [V, Mo]C particles and the matrix. Superior properties of high strength and low thermal expansion coefficient can be obtained by [V, Mo]C precipitation in alloy B with the addition of 0.4%V and 0.45%C.