• Analytical Science and Technology
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• v.27 no.1
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• pp.1-10
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• 2014

The $PM_{10}$ and $PM_{2.5}$ samples were collected at Gosan Site of Jeju Island, and analyzed, in order to investigate the size distribution and pollution characteristics of their components. $NH{_4}{^+}$, nss-$SO{_4}^{2-}$, $K^+$, and $CH_3COO^-$ were mostly existed in fine particles. Meanwhile, $NO{_3}{^-}$ was distributed in both fine and coarse particles, and $Na^+$, $Cl^-$, $Mg^{2+}$, nss-$Ca^{2+}$ were rich in coarse particle mode. The concentrations of nss-$Ca^{2+}$ and $NO{_3}{^-}$ were increased 36.7 and 3.2 times in coarse particles, and 15.0 and 3.1 times in fine particles during the Asian Dust periods. Especially, the concentrations of crustal elemental species such as Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba were highly increased for those periods. In the haze events, the concentrations of secondary air pollutants were increased 1.3~2.6 and 1.5~4.2 times in coarse and fine particles, respectively. Moreover, the remarkable increase of $NO{_3}{^-}$ concentration was also observed in fine particle mode. The factor analysis showed that the composition of coarse particles was influenced mainly by marine sources, followed by soil and anthropogenic sources. On the other hand, the fine particles were influenced by anthropogenic sources, followed by marine and soil sources.

• Analytical Science and Technology
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• v.9 no.3
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• pp.279-291
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• 1996

The new chelating resins, XAD-2, 4, 16-TAC and XAD-2, 4, 16-TAO were synthesized by Amberlite XAD-2, XAD-4, and XAD-16 macroreticular resins with 2-(2-thiazolylazo)-p-cresol(TAC) and 4-(2-thiazolylazo)orcinol(TAO) as functional groups and were characterized by elemental analysis and FT-IR spectrometry. It was found that the content of functional group in chelating resin was 0.60mmol/g in XAD-16-TAC and 0.68mmol/g in XAD-16-TAO respectively. The chelating resins were stable in acidic and alkaline solution and can be reused over 10 times. The sorption behavior of some metalions to two chelating resins was investigated by batch method, which included batch equilibrium, effect of pH, coexisting ions and masking agent. For the optimum condition of sorption, the time required for equilibrium was about 1 hour and optimum pH was 5. In the presence of anions such as ${SO_4}^{2-}$ and $CH_3COO^-$, the sorption of U(VI) ion was slightly reduced but other anions such as $Cl^-$ and $NO{_3}^-$ revealed no interference effect. Also, sorption capacity of U(VI) ion was decreased by addition of $CO{_3}^{2-}$ ion because of complex formation of $[UO_2(CO_3)_3]^{4-}$, but alkali metals and alkali earth metals including Na(I), K(I), Mg(II), and Ca(II) were not affected for the sorption extent. Masking agent, NTA showed better separation efficiency of U(VI) ion from coexisting metal ions such as Th(IV), Zr(IV), Hf(IV), Cu(II), Cd(II), Pb(II), Ni(II), Zn(II) and Mn(II) than EDTA, CDTA.

• Economic and Environmental Geology
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• v.45 no.1
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• pp.9-21
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• 2012

In this study, we investigated the chemical characteristics of soils collected from the several deserts and loess in China known as the typical source areas of Asian dust (the Taklamakan desert, the Alashan desert, the Ordos desert and the Loess Plateau). Based on our analysis, we examined the possibility of adverse effects on environments and human health. In each desert and loess, major elemental compositions of soils did not show large variations, implying that the long-periodic mixing of soils in each area made their chemical compositions homogeneous. Minor elements of soils in each desert and loess showed more complicated patterns with strong correlations each other (e.g., Cr, Cu, As, Co, Ni, V, Y, Sc, Sn, Pb, Zn, Cd, Cs, Li, Th, U). These results thus enable us to discriminate the soil of the Loess Plateau from those of the other deserts in China. The results of sequential extraction experiments for soils showed that the chemical speciation of Fe was dominant in residual fraction (>85%) in all deserts and loess, but the fractions of Mn and Ca chemical speciations were very different in each area. In the case of Mn, the fraction of amorphous Fe-Mn hydroxides (55.4%) in the Central Loess Plateau and the carbonate fraction (33.8%) in Taklamakan desert were higher as much as 2 to 5 times than other deserts. The chemical speciations of Ca are dominant in carbonate fraction in Taklamakan (75.9%) and Alashan (50.5%) deserts, but carbonate fractions of Ca in the Loess Plateau and Ordos deserts were low (6.6% and 2.1%, respectively). According to the mobility of trace elements inferred from the results of sequential extraction procedure, we could classify them into five groups, and the mobility of Cd, Pb and Cu are more than 87%, 33% and 30%, respectively. Therefore, Cd, Pb and Cu in soils of deserts and loess could be easily dissolved when interacted with surface water. As such, they could give adverse effects on surficial environments and human health.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.378-384
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• 2018

$C_9H_7NHCrO_3Cl$ was synthesized by reacting $C_9H_7NH$ with chromium (VI) trioxide. The structure of the product was characterized by FT-IR (Fourier transform infrared) spectroscopy and elemental analysis. The oxidation of benzyl alcohol by $C_9H_7NHCrO_3Cl$ in various solvents showed that the reactivity increased with increasing dielectric constant(${\varepsilon}$) in the following order: DMF (N,N'-dimethylformamide) > acetone > chloroform > cyclohexane. The oxidation of alcohols was examined by $C_9H_7NHCrO_3Cl$ in DMF. As a result, $C_9H_7NHCrO_3Cl$ was found to be an efficient oxidizing agent that converts benzyl alcohol, allyl alcohol, primary alcohols, and secondary alcohols to the corresponding aldehydes or ketones (75%-95%). The selective oxidation of alcohols was also examined by $C_9H_7NHCrO_3Cl$ in DMF. $C_9H_7NHCrO_3Cl$ was the selective oxidizing agent of benzyl, allyl and primary alcohol in the presence of secondary ones. In the presence of DMF with an acidic catalyst, such as $H_2SO_4$, $C_9H_7NHCrO_3Cl$ oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, and $m-NO_2$). Electron donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.69 (308K). The observed experimental data were used to rationalize hydride ion transfer in the rate-determining step.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1337-1346
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• 2006

Soil humin is the insoluble fraction of humic materials and play an important roles in the irreversible sorption of hydrophobic organic contaminants onto soil particles. However, there have been limited knowledge about the sorption and chemical properties of humin due to the difficulties in its separation from the inorganic matrix(mainly clays and oxides). In this study, de-ashed soil humins($Hu_1-Hu_6$) were isolated from a soil residues(Crude Hu) after removing alkali-soluble organic fractions followed by consecutive dissolution of the mineral matrix with 2%-HF for 2 hr. The humin samples were characterized by elemental analysis and $^{13}C$ NMR spectroscopic method and their sorption-desorption behavior for 1-naphthol were investigated from aqueous solution. The results were compared one another and that with peat humin. $^{13}C$ NMR spectra features indicate that the soil humin molecules are mainly made up of aliphatic carbons(>80% in total carbon) including carbohydrate, methylene chain. Freundlich sorption parameter, n was increased from 0.538 to 0.697 and organic carbon-normalized sorption coefficient(log $K_{OC}$) values also increased from 2.43 to 2.74 as inorganic matrix of the soil humin removed by HF de-ashing. The results suggest that inorganic phase in humin plays an important, indirect role in 1-naphthol sorption and the effects on the sorption non-linearity and intensity are analyzed by comparison between the results of soil humin and peat humin. Sorption-desorption hysteresis were also observed in all the humin samples and hysteresis index(HI) at low solute concentration($C_e$=0.1 mg/L) are in order of Peat humin(2.67)>De-ashed humin(0.74)>Crude Hu(0.59).

• Applied Biological Chemistry
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• v.41 no.1
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• pp.110-117
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• 1998

Seven kinds of polyphenol compounds having ACE activities were isolated and purified by Sephadex LH-20, MCI-gel CHP-20, ${\um}-Bondapak\;C_{18}$ and Fuji-gel ODS $G_3$ sucessively from cacao bean(Ghana). The chemical structures of each compound were determined and identified using analyzers such as $^1H-NMR$, $^{13}C-NMR$, IR, MS, polarimeter and Elemental Analysis. Inhibition effects of isolated polyphenols on angiotensin converting enzyme (concerned with hypertension) were also observed. The results obtained were as follows,; The compounds isolated and identified were confirmed and determined as compound 1 [(+)-catechin], compound 2 [(-)-epicatechin], compound 3 [procyanidin B-1 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(+)catechin], compound 4 [procyanidin B-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin], compound 5 [procyanidin B-7 : (-)-epicatechin-$(4{\beta}{\rightarrow}6)$-(+)-catechin], campound 6 (procyanidin B-2,3,3'-O -digallate), compound 7 [cinnamtannin A-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin]. In the inhibition effect on ACE, procyanidin B-2,3,3'-O-digallate (compound 6) showed a higher value of 94.6% for ACE in $100\;{\um}M$ than other compounds such as (+)-catechin (compound 1), (-)-epicatechin (compound 2), procyanidin B-1 (compound 3), procyanidin B-2 (compound 4), procyanidin B-7 (compound 5) and cinnamtannin A-2 (compound 7) showing 67.9%, 61.9%, 88.6%, 82.5%, 72.2% and 82.3% for ACE, respectively. Inhibition of $4{\beta}{\rightarrow}8$ in coupling bond on the ACE enzyme was more effective than that of $4{\beta}{\rightarrow}6$. Procyanidin containing gallate inhibited more effectively than those containing not any. It was also observed that a lot of hydroxy group in the compounds increased the inhibitory effect.

• Journal of the Korean Chemical Society
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• v.40 no.1
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• pp.28-36
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• 1996

The pentanuclear complexes have been obtained by the reactions of molybdenum(VI) and tungsten(VI) polynuclear complexes with molybdenum(O) and tungsten(O) dinitrosyl mononuclear complexes, and methylthioamidoxime. The prepared complexes (n-Bu4N)2[Mo4O12Mo(NO)2{CH3SCH2C(NH2)NHO}2{CH3SCH2C(NH)NO}2](1), (n-Bu4N)2[W4O12Mo(NO)2{CH3SCH2C(NH2)NHO}2{CH3SCH2C(NH)NO}2](2), (n-Bu4N)2[Mo4O12W (NO)2{CH3SCH2C(NH2)NHO}2{CH3SCH2C(NH)NO}2] (3) have been characterized by elemental analysis, infrared, UV-visible and 1H NMR spectra. The complexes are elucidated the cis-{M(NO)2}2+(M = Mo, W) unit and a slight delocalization by spectroscopy. The structure of (n-Bu4N)2[W4O12Mo(NO) 2{CH3SCH2C(NH2)NHO}2{CH3SCH2C(NH)NO}2] was determined by X-ray single crystal diffraction. Crystal data are follows: Monoclinic, $P21}a$, a = 22.14(2) $\AA$, b = 14.93(1) $\AA$, c = 23.20(1) $\AA$, $\beta$ = 111.08(6) $\AA$, V = 7155(9) $\AA$, Z = 4, final R = 0.072 for 6191(I > $3\sigma(I)).$ The structure of complex forms two dinuclear [W2O5{CH3SCH2C(NH2)NHO}{CH3SCH2C(NH)NO}] and a central {Mo(NO)2} 2+ core. The geometric structure of the {Mo(NO)2} 2+unit is the formally cistype and C2v symmetry.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.897-905
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• 2013

In this study, sorption coefficients (${\log}K_{OC}$, n) for the binding of phenanthrene (PHE) to soil humins, insoluble fraction of soil humc substances (HS), were determined and relationship between the sorption coefficients and structural characteristics of the soil humins were investigated. The soil humins used in the present study were isolated from 7 different soils including 5 domestic soils, an IHSS standard and a peat soil, and characterized by elemental analysis and CPMAS $^{13}C$ NMR method. $^{13}C$ NMR spectral features indicate that the soil humins are mainly made up of aliphatic carbons (57.1~72.3% in total carbon) with high alkyl-C moiety, and the alkyl-C contents ($C_{Al-H,C}$, %) was in order of granite soil Hu (26~42%) > volcanic ash soil, HL Hu (23.9%) > Peat Hu (14.0%). The results of correlation study show that a positive relationship ($r^2$ = 0.77, p < 0.05) between organic carbon normalized-sorption coefficients ($K_{OC}$, mL/g) and alkyl-C contents($C_{Al-H,C}$, %), while negative relationship ($r^2$ = (-)0.74, p < 0.05) between Freundlich sorption parameter (n) and H,C-substituted aromatic carbon contents ($C_{Ar-H,C}$, %). The magnitude of $K_{OC}$ values are also negatively well correlated with polarity index (e.g., PI, N + O)/C) ($r^2$ = (-)0.74, p < 0.1). These results suggest that the binding capacity (e.g., $K_{OC}$) for PHE is increased in soil humin molecules having high contents of alkyl-C or lower polarity, and nonlinear sorption for PHE increased as the H,C-substituted aromatic carbon contents ($C_{Ar-H,C}$, %) in the soil humins increased. The PHE sorption characteristics on soil humins are discussed based on the dual reactive mode of sorption model.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.549-557
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• 2006

The characteristics of supercritical water oxidation have been studied to decompose the waste anionic exchange resins which were produced from a power plant. The waste resins from a power plant were mixture of anionic and cationic exchange resins. The waste anionic exchange resins had been separated from the waste resins using a solid-liquid fluidized bed. It was confirmed that the cationic exchange resins were not included in the separated anionic exchange resins by the elemental and thermogravimetric analysis. A slurry of anionic exchange resins which could be fed continuously to a supercritical water oxidation apparatus by a high pressure pump was prepared using a wet ball mill. Although the COD of liquid effluent had been reduced more than 99.9% at 25.0 MPa and $500^{\circ}C$ within 2 min, the total nitrogen content was reduced only 41%. The addition of nitric acid to the slurry could reduce the total nitrogen content in treated water. The central composite design as a statistical desist of experiments had been applied to optimize the conditions of decomposing anionic resin slurry by means of the COD and total nitrogen contents in treated waters as the key process output variables. The COD values of treated waters had been reduced sufficiently to $99.9{\sim}100%$ af the reaction conditions of $500{\sim}540^{\circ}C$, 25.0 MPa within 2 min. The effects of temperature and nitric acid concentration on COD were not significant. However, the effect of nitric acid concentration on the total nitrogen was found to be significant. The regression equation for the total nitrogen had been obtained with nitric acid concentration and the coefficient of determination($r^2$) was 95.8%.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.541-550
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• 2010

A new $N_4O_3$ heptadentate ligand, N,N'-Bis(2-hydroxybenzyl)-1,3-bis[(2-aminoethyl)amino]-2-propanol(H-BAP 4HCl)was synthesized. The hydrochloric acid salts of Br-BAP 4HCl, Cl-BAP 4HCl, $CH_3O$-BAP 4HCl and $CH_3$-BAP 4HCl containing Br-, Cl-, H-, $CH_3O-$ and $CH_{3^-}$ groups at the para-site of the phenol group of the H-BAP were synthesized. The structures of the ligands were confirmed by C. H. N. atomic analysis and $^1H$ NMR, $^{13}C$ NMR, UV-visible and mass spectra. The elemental stepwise protonation constants(${logK_n}^H$) of the synthesized $N_4O_3$ ligands showed six steps of the proton dissociation. The orders of the overall dissociation constants($log{\beta}_p$) of the ligands were Br-BAP < Cl-BAP < H-BAP < $CH_3O$-BAP < $CH_3$-BAP. The orders agreed well with that of Hammett substituent constants($\sigma_p$). The calculated stability constants($logK_{ML}$) between the ligands and transition metal ions agreed well with the order of the overall proton dissociation constants of the ligands but they showed a reverse order in Hammestt substituent constants($\sigma_p$). The order of the stability constants between the transition metal ions with the ligands were Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II).