• 제목/요약/키워드: Water-soluble ions

검색결과 135건 처리시간 0.028초

Heavy Metal Contamination in Surface Water Used for Irrigation: Functional Assessment of the Turag River in Bangladesh

  • Arefin, M. Taufique;Rahman, M. Mokhlesur;Wahid-U-Zzaman, M.;Kim, Jang-Eok
    • Journal of Applied Biological Chemistry
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    • 제59권1호
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    • pp.83-90
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    • 2016
  • The aim of the present study was to evaluate the degree of metal contamination of the Turag River water and its suitability for irrigation. Twenty water samples were analyzed for physicochemical parameters and metals viz., calcium, magnesium, potassium (K), sodium, copper (Cu), zinc (Zn), iron (Fe), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni). All water samples were slightly alkaline to alkaline. Regarding electrical conductivity (EC), all samples were suitable for crop in soils with moderate permeability and leaching. Water samples were medium salinity and low alkalinity hazard classes. In terms of total dissolved solids (TDS), all samples were classified as freshwater. As per sodium adsorption ratio (SAR) and soluble sodium percentage (SSP), all samples were classified as excellent. No residual sodium carbonate (RSC) was detected in any of the samples, indicating suitability for irrigation; and all samples were considered very hard. Cr and Mn contents in all samples were above FAO guideline values and, therefore, these metals were considered toxic. Zn, Cu, Pb, Cd, and Ni concentrations were below acceptable limit for irrigation and do not pose a threat to soil environment. Significant relationships were found between EC and TDS, SAR and SSP, SAR and RSC, and SSP and RSC. The combinations of ions such as K-Zn, K-Fe, K-Cu, K-Mn, K-Pb, Zn-Fe, Zn-Cu, Zn-Mn, Fe-Mn, Cu-Mn, Cu-Pb and Mn-Pb exhibited significant correlation. This study revealed that Turag River water samples are contaminated with Cr and Mn. This fact should not be ignored because water contamination by metals may pose a threat to human health through food chain.

장기간 (1990 ~ 2012) 측정자료를 이용한 용인-수원지역에서의 PM2.5의 화학적 특성연구 및 헤이즈와 황사 현상 시 화학성분별 질량분율표의 개발 (Study on Chemical Characterization of PM2.5 based on Long-term Database (1990 ~ 2012) and Development of Chemical Species Profiles During Haze Days and Asian Dust Days in Yongin-Suwon Area)

  • 임효지;이태정;김동술
    • 한국대기환경학회지
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    • 제31권3호
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    • pp.223-238
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    • 2015
  • The $PM_{2.1}$ was collected by LVCI (low volume cascade impactor) during Group-A Period (September 1990 to December 2012) and the $PM_{2.5}$ was collected by HVAS (high volume air sampler) during Group-B Period (September 2009 to April 2012) at Kyung Hee University, Global Campus located on the boarder of Yongin and Suwon. The 8 water-soluble ions ($Na^+$, $NH_4{^+}$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $ NO_3{^-}$, and $SO_4{^{2-}}$) were analyzed by IC, and the 14 inorganic elements (Al, Mn, Si, Fe, Cu, Pb, Cr, Ni, V, Cd, Ba, Zn, Ti, Ag) were analyzed by XRF and ICP-AES after performing proper pre-treatments of each sample filter. The average total mass fractions of $SO_4{^{2-}}$, $NO_3{^-}$, and $NH_4{^+}$+ to $PM_{2.5}$ samples during Group-B Period were 0.39 in normal days, 0.44 in haze days, and 0.27 in Asian dust days, respectively; however, the average total mass fractions of Al, Fe, and Si to $PM_{2.5}$ mass were 0.043 in normal days, 0.021 in haze days, and 0.036 in Asian dust days, respectively. Especially the concentration of Pb was significantly decreased during Group-B Period rather than during Group-A Period, while Cr and Ni was increased during Group-B Period. In this study, we intensively compared the annual and seasonal patterns of major chemical species among normal days, haze days, and Asian dust days. Further we developed mass fraction profiles by collecting episode cases of haze days and Asian dust days, which were consisting of 22 chemical species. Those profiles are considered to be useful when applying various receptor models and establishing air quality management plans near future.

밀양지역의 PM2.5 농도 및 성분특성 (The PM2.5 Concentration and Components Characteristics in Miryang)

  • 서정민;김영식;전보경;최금찬;류재용;박정호
    • 한국환경과학회지
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    • 제16권12호
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    • pp.1355-1367
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    • 2007
  • This study summarizes the relations among $PM_{2.5}$ concentration, water-soluble ions concentration, metallic element Components characteristics and SPSS in negative ion and metallic element of $PM_{2.5}$ particle in Miryang.(By the urban area, the industrial complex area and the suburban area according to the season) $PM_{2.5}$ concentration of total 72 samples collected from 3 sites turned out to range from 3.47 to 34.7 ${\mu}g/m^3$, and the average concentration was the suburban area-the kin nup(16.00 ${\mu}g/m^3$) > the urban area-the roof of the old Miryang university(10.32 ${\mu}g/m^3$) > the industrial complex-Sapo industrial complex(10.29 ${\mu}g/m^3$). In particular, the suburban area had $PM_{2.5}$ concentration 1.5 times those of urban area, industrial complex. It was thought although the site was suburban and farm-side without pollutants around, it had a higher concentration value influenced by external factors including the brickyard, small-scale incinerator, driving range construction, construction on the Daegu-Busan express and the widening of the four-lane road between Miryang-Anyang nearby. As for water-soluble ions among $PM_{2.5}$ particle collected in Miryang area, $SO4_{2^-}$ accounted for 60% and $NO_{3^-}$, was 30% in spring and summer. And $NO_{3^-}$ accounted for 50% and $SO4_{2^-}$ was 35% in fall and winter. The AI value of metallic Components among $PM_{2.5}$ particle collected in Miryang area had a high value influenced by the apartment complex construction and the extension work of road. The industrial complex area had Zn concentration 3 times, and Fe concentration 2 times those of urban area and suburb area. When it comes to the relation with metallic elements in urban area, the highest coefficient of correlation was between Cr-Fe with 0.85, and Pb-Cd turned out in the reverse correlation. Among metallic elements, the coefficients of correlation between Zn and Cr, Mn, Fe, NI were high in industrial complex area. The highest coefficient of correlation was between Mn-Zn with 0.88, meanwhile Ni and Cu, Cd turned out in the reverse correlation in the suburb area. These coefficients of correlation are attributed to the difference in pollutant sources, rather than difference in pollutant and non-pollutant.

대전지역 대기 중 PM2.5의 유기탄소와 원소탄소의 계절별 특성 연구 (Seasonal Characteristics of Organic Carbon and Elemental Carbon in PM2.5 in Daejeon)

  • 김효선;정진상;이진홍;이상일
    • 한국대기환경학회지
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    • 제31권1호
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    • pp.28-40
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    • 2015
  • To investigate the seasonal variations of carbonaceous aerosol in Daejeon, OC (organic carbon), EC (elemental carbon) and WSOC (water soluble organic carbon) in $PM_{2.5}$ samples collected from March 2012 to February 2013 were analyzed. $PM_{2.5}$ concentrations were estimated by the sum of organic matter ($1.6{\times}OC$), EC, water-soluble ions ($Na^+$, $NH_4{^{+}}$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^{2-}}$, $NO_3{^{-}}$). The estimated $PM_{2.5}$ concentrations were relatively higher in winter ($29.50{\pm}12.04{\mu}g/m^3$) than those in summer ($13.72{\pm}6.92{\mu}g/m^3$). Carbonaceous aerosol ($1.6{\times}OC+EC$) was a significant portion (34~47%) of $PM_{2.5}$ in all season. The seasonally averaged OC and WSOC concentrations were relatively higher in winter ($6.57{\times}3.48{\mu}gC/m^3$ and $4.07{\pm}2.53{\mu}gC/m^3$ respectively), than those in summer ($3.07{\pm}0.8{\mu}gC/m^3$, $1.77{\pm}0.68{\mu}gC/m^3$, respectively). OC was correlated well with WSOC in all season, indicating that they have similar emission sources or formation processes. In summer, both OC and WSOC were weakly correlated with EC and also poorly correlated with a well-known biomass burning tracer, levoglucosan, while WSOC is highly correlated with SOC (secondary organic carbon) and $O_3$. The results suggest that carbonaceous aerosol in summer was highly influenced by secondary formation rather than primary emissions. In contrast, both OC and WSOC in winter were strongly correlated with EC and levoglucosan, indicating that carbonaceous aerosol in winter was closely related to primary source such as biomass burning. The contribution of biomass burning to $PM_{2.5}$ OC and EC, which was estimated using the levoglucosan to OC and EC ratios of potential biomass burning sources, was about $70{\pm}15%$ and $31{\pm}10%$, respectively, in winter. Results from this study clearly show that $PM_{2.5}$ OC has seasonally different chemical characteristics and origins.

미역 포자엽에서 분리한 항산화 물질의 특성 (Characterization of an Antioxidant from Sporophyll of Undaria pinnatifida)

  • 양지영;유미영;김상권
    • 한국미생물·생명공학회지
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    • 제32권4호
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    • pp.307-311
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    • 2004
  • 미역포자엽으로부터 열수추출을 통해 항산화물질을 조제하고 항산화와 관련된 특성을 조사하였다. 미역포자엽으로부터 조제한 열수추출물은 시료 양에 따라 2차곡선의 항산화능을 보여주었으며 $IC_{50}$ 의 값은 1.54 mg을 나타내었다. 이는 ascorbic acid 0.005 mg과 BHT 0.05 mg 에 비해서는 높은 값을 나타내었다. 미역포자엽으로부터 조제한 열수추출물의 pH안정성은 산성과 중성에서는 안정하였으나 알카리영역에서는 급격히 감소하였다. 또한 열안정성은 0도에서 120도의 모든 범위에서 안정한 값을 유지하였다. 미역포자엽으로부터 조제한 열수추출물의 금속이온과 EDTA가 항산화능에 미치는 영향을 조사한 결과 $Cu^{2+}$, $Co^{2+}$, $Mn^{2+}$ 등의 금속이온이 활성이 증가하는 결과를 보여주었으며 EDTA는 저해하는 결과를 보여주었다.

Interaction of the Post-transition Metal Ions and New Macrocycles in Solution

  • Jung, Oh-Jin
    • Bulletin of the Korean Chemical Society
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    • 제14권6호
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    • pp.687-691
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    • 1993
  • Complexation of $Cd^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions with four cryptands were studied by potentiometry and solution calorimetry in various weight percent methanol-aqueous solvent at 25${\circ}$C under $CO_2$free nitrogen atmosphere. The stabilities of the complexes were dependent on the cavity size of macrocycles. The $Hg^{2+}$ ion stability constants are higher than those of $Cd^{2+}\;and\;Pb^{2+}$ ion. All the cryptands formed complexes having 1 : 1 (metal to ligand) mole-ratio except for $Hg^{2+}-L_1$ (cryptand 1,2b: 3,5-benzo-9,14,17-trioxa-1,7-diazabicyclo-(8,5,5) heptadecane) and $Cd^{2+}-L_2$ (cryptand 2,2b: 3,5-benzo-10,13,18,21-tetraoxa-1,7-diazabicyclo (8,5,5) eicosane) complexes. $Hg^{2+}-L_1$ complex was a sandwitch type, and the $Cd^{2+}-L_2$ complex showed two stepwise reactions. Thermodynamic parameters of the $Cd^{2+}-L_2$ complex were $6.08(log\;K_1)$, -7.28 Kcal/mol $({\Delta}H_1)$, and $4.78\;(log\;K_2)$, -4.62 Kcal/mol $({\Delta}H_2)$, respectively, for 1 : 1 and 2: 1 mole-ratio. The sequences of the selectivity were increased in the order of $Hg^{2+}\;>Pb^{2+}\;>Cd^{2+}$ ion for $L_3\;and\;L_4$ macrocycles, and the $L_2$-macrocycle has a selectivity for $Cd^{2+}$ ion relative to $Zn^{2+},\;Ni^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions. Thus, it is expected that the $L_2$ can be used as carrier for seperation of the post transition metals by macrocycles-mediated liquid membrane because $L_2$ is not soluble in water, and the difference of stability constants of the metal complexes with $L_2$ are large as compared with the other transition metal complexes. The $^1H\;and\;^{13}C-NMR studies indicated that the nitrogen atoms of cryptands have greater affinity to the post transition metal ions than the oxygen atoms, and that the planarities of the macrocycles were lost by complexation with the metal ions because of the perturbation of ring current of benzene molecule attached to macrocycles and counter-anions.

한강의 영양염류 및 주요이온류의 년변화와 그 수질적고찰 (Seasonal Variations in Nutrients and Principal Ions Contents of the Han River Water, and its Water Characteristics)

  • 최상;정태화;곽희상
    • 한국해양학회지
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    • 제3권1호
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    • pp.26-38
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    • 1968
  • 우리의 사회생활이 발달함에 따라 물의 사용량은 많아지고 그 용도도 다기다양하게된다. 인구증가와 생활향상에 의한 가정용수의 증가, 각종 공업 및 산업의 발달에 따르는 이것들의 폐수들은 모두가 하천으로 흘러내려, 하천수를 오염할뿐 아니라 이것들은 결국 바다로 유입되어 연안일대의 수질을 악화시켜, 연안어업 및 연안어족의 산란 및 성육장을 파괴하는 경우가 적지않다. 하천, 호소등의 자연수는 그것들이 지니고 있는 속성을 충분히 활용하면서 영구히 보존되어야할 귀중한 자원이며, 그곳의 생물자원의 함양은 물론이거니와 음료수로서 또 각종 산업용수로서 그 용도가 다양하게 충족되어야 할 것이다. 우리나라의 하천수는 아직은 인위적인 오염도가 적다고 할 수 있다. 그러나 이것을 무관심하게 방치해두면 기필코 멀지않는 장래에 심한 오염이 있게 될 것이며, 여기에 대한 적절한 대책이 하루 속히 강구되어야 한다고 생각된다. 우리나라 하천수계의 수질적연구는 극히 희소하다. 창무 태전(1944)등 1∼2의 공헌이 있었을뿐 거의 연구가 되어있지 않다. 만일 우리나라 하천수계의 수질이 현재 아직 그다지 오염되지 안했다는 전제가 허용된다면, 현재의 각하천의 수질적특성은 그 유역으 흐르면서 각종물질을 용해시켜 또 포함한 총합적이고도 자연적인 결과로서 받아들일수 있으며, 이 자료는 장래에 있을 우리나라의 수질규제에 규준적인 역할을 하게 될것이라고 하겠다.

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수피조성분에 의한 중금속 흡착 (Adsorption of Heavy Metal Ions by Constituents of Bark)

  • 백기현;최인규;신금
    • Journal of the Korean Wood Science and Technology
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    • 제24권3호
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    • pp.51-56
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    • 1996
  • The Bark lignin(alkali- and acid lignin), bark extractives(hot water-and $Na_2SO_3$ extractives) of Quercus acutissima and Pinus densiflora, and flavonoids were used to detect heavy metal adsorption. The adsorption ratio of heavy metals by lignin was assigned for 40 to 50%, but was not dependent on lignin kinds. However, in case of the addition of light metals such as $Ca^{++}$ and $Mg^{++}$ to lignin the adsorption ratio was increased by 20 to 40%, and $Pb^{++}$ was almost completely adsorbed. On hot water extractives, the adsorption ratio was very low because the substrate was water-soluble, so the substrate should be water-insoluble to adsorb the heavy metals. However, the adsorption ratios of $Cd^{++}$ and $Pb^{++}$ on $Na_2SO_3$ extractives were significantly increased, while those of $Zn^{++}$ and $Cu^{++}$, were similar to lignin. When four kinds of heavy metals were treated to $Na_2SO_3$ extractives together, more than 97% of $Pb^{++}$ and $Cu^{++}$ was adsorbed_ and $Zn^{++}$ was more adsorbed by 40%, and $Cd^{++}$ was not changed, comparing with the case that on kind of heavy metal was treated. There were differences between adsorption ratio of the kinds of flavonoids and heavy metals, and the adsorption ratio of heavy metals was assigned to 20 to 45% per 0.1g flavonoid.

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Formation of a Unique 1:2 Calcium-Calixquinone Complex in Aqueous Media

  • Kang, Sun-Kil;Lee, One-Sun;Chang, Suk-Kyu;Chung, Doo-Soo;Kim, Ha-Suck;Chung, Taek-Dong
    • Bulletin of the Korean Chemical Society
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    • 제32권3호
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    • pp.793-799
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    • 2011
  • We report the complexation behavior of calix[4]arenemonoquinone-triacid (CTAQ), which is an electroactive and water-soluble receptor for calcium ion. UV-visible and NMR spectroscopic studies revealed that CTAQ in aqueous media forms 1:2 as well as 1:1 (metal ion:CTAQ) stoichiometric complexes with $Ca^{2+}$, $Sr^{2+}$, and $Ba^{2+}$ ions. The nonlinear fitting of titration curves based on UV-visible absorption spectra showed that the binding constants of CTAQ for $Ca^{2+}$ ion are 4 $({\pm}2){\times}10^6\;M^{-1}$ for 1:1 and 1.4 $({\pm}0.5){\times}10^{11}\;M^{-2}$ for 1:2 complex. NMR conformational studies and the titration curves corroborate that the $Ca^{2+}$:CTAQ complex in aqueous solution is not present in the form of merely 1:1 one, being consistent with UV-visible spectrophotometric results. The Monte Carlo simulation supports the presence of a stable conformer of 1:2 complexes in which a $Ca^{2+}$ ion is interposed between two CTAQs at the global minimum. This is the first model of 1:2 stoichiometric complex of calix[4]arene and alkaline earth ions in aqueous media.

1-Methylcyclopropene(1-MCP) 및 $CO_2$ 처리가 복숭아(Prunus persica) 과실의 경도와 세포벽 변화에 미치는 영향 (Effect of 1-MCP and High $pCO_2$ Treatment on the Firmness and Pectin Changes in Peach(Prunus persica) Fruit During Shelf-life)

  • 김명선;민정호;천종필;김진국;이은모;이지용;황용수
    • 농업과학연구
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    • 제37권2호
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    • pp.209-216
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    • 2010
  • In order to understand the effects of a single or combined treatments of 1-MCP($1{\mu}L/L$) and $CO_2$(100%) on the firmness of melting type peach fruit(cv. Chunjungdo), fruit were harvested at commercial maturity and examined physiological changes including flesh firmness during 10 days of shelf-life. Firmness loss of fruit was delayed by both single and combined treatments of 1-MCP and $CO_2$. The treatment of 1-MCP was more effective than $CO_2$ treatment but no additive effective on firmness retention was found in the combined treatment. The upsurge of ethylene evolution occurred 5 days of shelf-life in air treated control but ethylene evolution gradually increased in fruit treated by 1-MCP and 1-MCP+$CO_2$. The suppression of ethylene evolution seemed stronger in $CO_2$ treatment. The respiration of fruit significantly inhibited up to 10 days except control where climacteric increase of respiration was found at 10 days of shelf-life. A molecular shift of pectic polymers(an increase of chelator soluble pectins and decrease of water soluble pectins) was induced by both 1-MCP and $CO_2$ treatments. An increase of water soluble pectins was coincident with firmness loss. The delay of firmness loss seemed to be associated with the migration of calcium to wall matrix, especially pectins, resulting in the increase of wall bound calcium. The polygalacturonase activity was significantly reduced by 1-MCP alone 1 day after treatment and increased to similar level of activity 5 days after treatment compared to other treatment except air treated control whereas pectin methylesterase activity seemed not to be affected by both 1-MCP and $CO_2$ treatments. Thus, the molecular shift of pectic polymers appeared not to be related with pectin methylesterase. Further study is required to clarify the softening mechanism associated with molecular shift of pectic polymers and the inter- or intra-cellular movement of calcium ions induced by postharvest treatments of 1-MCP and $CO_2$.