• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1832-1838
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• 2006

The present paper is focused on sorption concentration of silver (I) on some complex-forming ion exchangers in the initial thiocyanate form and subsequent determination of Ag(I) in the phase of anion exchanger AN-25 by diffuse reflectance spectroscopy. The sorption and kinetic characteristics of the sorbents were investigated. The apparent stability constants of thiocyanate silver complexes in the ion exchanger phase were calculated. The sorption-spectroscopic method is proposed for Ag(I) determination in aqueous solutions. The calibration curve is linear in the concentration range of 10-200 mg/L (sample volume is 10.0 mL) and the detection limit is 2 $\mu$g/mL. The presence of $Na^+,\;K^+,\;Mg^{2+}$ (macrocomponents) as well as of Ni (II), Co (II), Cu (II) do not hinder the determination of silver (I).

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.401.1-401.1
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• 2002

Potentiometric sensors are important and viable devices for use in pharmaceutical analysis. liquid polymeric membrane electrodes for many basic drugs and a few acidic drug were reported. The acidic drug-metal(Ⅱ)-triethylene tetramine ion pair complexes were prepared and used in poly(vinyl chloride) membrane electrodes to analyze anionic drugs such as mefenamic acid and ibuprofen. Metal ion used were Fe2＋. Co2＋. Ni2＋ and Cu2＋. Plasticizer used was o-nitrophenyl octyl ether.. (omitted)

• Mycobiology
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• v.40 no.1
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• pp.20-26
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• 2012

The complexes of tailor made ligands with life essential metal ions may be an emerging area to answer the problems of multi drug resistance. The coordination complexes of VO(II), Co(II), Ni(II) and Cu(II) with the Schiff bases derived from isatin with 3-chloro-4-floroaniline and 2-pyridinecarboxaldehyde with 4-aminoantipyrine have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, molar conductance, electronic spectra, FT-IR, FAB mass and magnetic susceptibility measurements. FAB mass data show degradation of complexes. Both the ligands behave as bidentate and tridentate coordinating through O and N donor. The complexes exhibit coordination number 4, 5 or 6. The Schiff base and metal complexes show a good activity against the bacteria; $Staphylococcus$ $aureus$, $Escherichia$ $coli$ and $Streptococcus$ $fecalis$ and fungi $Aspergillus$ $niger$, $Trichoderma$ $polysporum$, $Candida$ $albicans$ and $Aspergillus$ $flavus$. The antimicrobial results also indicate that the metal complexes are better antimicrobial agents as compared to the Schiff bases. The minimum inhibitory concentrations of the metal complexes were found in the range 10-40 ${\mu}g/mL$.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.543-551
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• 1985

A new class of polyhydrazones has been synthesized by the solution polycondensation from equimolecular amounts of aromatic dialdehydes such as para, meta, ortho-phthal aldehyde, 5,5'-methylene-bis-salicyl aldehyde (PPTA, MPTA, OPTA, MBSA) and dihydrazides, 5,5'-methylene-bis-salicylic dihydrazide (MBSDH), terephthalic dihydrazide (TDH), sebacic dihydrazide (SDH) in DMF-$CH_3COOH$ solution. The solubility characteristics, spectral, and thermal properties of the synthesized polyhydrazones and their metal chelates were also studied. These polyhydrazones and their metal chelates except the polyhydrazone prepared from OPTA-MBSDH were generally insoluble in common organic solvents. The thermogravimetric analysis of polyhydrazones showed 10% weight losses at 250∼350$^{\circ}$C and residual weight at 500$^{\circ}$C were 32.5∼62.5%. The decomposition temperature of higher relatively, and the metal chelates decrease in the following orders; Zn(II)-IIa > Ni(II)-IIa > Co(II)-IIa > Cu(II)-IIa.

• Analytical Science and Technology
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• v.9 no.1
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• pp.26-34
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• 1996

A method to determine the trace amount of Se and Bi in the scalp hair using the hydride generation inductively coupled plasma atomic emmission spectrometry was studied. The optimum operation conditions of ICP for hydride generation are 0.6~0.8L/min for the carrier gas flow rate, and 6mm above the induction coil for the observation height. Hydrochloric acid concentrations for the optimum hydride generation conditions were greater than 1.5M when 2.5% $NaBH_4$ and NaOH were used, and greater than 0.5M when 2.5% $NaBH_4$ and 0.1% NaOH were used. Severe interference effects are observed from transition metals such as Cu and Ni, and they could be circumvented by the coprecipitation with lanthanum hydroxide.

• Analytical Science and Technology
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• v.13 no.3
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• pp.297-303
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• 2000

Isotope-dilution inductively coupled plasma mass spectrometry was used to determine trace amounts of Cd, Cu, Pb, Ni and Zn in sediment. Sediment samples were dissolved by microwave digestion with addition of mixed acid ($HNO_3$, HF and $HClO_4$). Lead was determined after separation of alkaline and alkaline earth metals by an ammonium pyrrolidenedithiocarbarmate (APDC) solvent extraction. The other elements were determined after separation of iron, tin and titanium by hydroxide precipitation. Recovery efficiency of the analyte elements was not satisfactory, but most of matrix elements causing the isobaric interference could be effectively eliminated by the separation. Good agreement was achieved with the certified values in the analysis of the two sediment reference materials.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.9-18
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• 1986

For identification and apportionment of sources emitting particulate matters in environment, the multi-elemental characterization of size-density fractionated particulate matters was carried out. Eight types of samples were tested; soil, flyash released from burning of bunker-Coil, diesel oil, coal, and soft coal, urban road-way dust, urban dust fall, and airborne particulate matter. The fractions of particulate matters obtained by heavy liquid separation methos with a series of dichloromethane-bromoform were then analyzed using atomic absorption spectrophotometry for Ni, Cr, Cu, An, Fe, Al, and Mg. Each sample showed a different concentration profile as a function of density, and a number of useful conclusions concerning characterization of elemental distribution were obtained. From the density distributions of elements in soil, the maximum value was found for all elements in the density range of 2.2 $\sim 2.9g.cm^{-3}$, including the density of $SiO_2$. However, the distribution of metallic compounds with the density lower than $2.2g.cm^{-3}$ was prevalent in urban roadway dust, urban dust fall, and airborne particulate matter. And the density distribution curves of these urban dusts also have the higher distribution at the density of 2.2 - 2.9g.cm^{-3}$, including the density of wind-blown silica. This tendency generally was prevalent in the natural source elements, such as Al, Fe, Mn, and Mg. The maximum values were found in the density ranges of 1.3 $\sim 2.2g.cm^{-3}$ from the density distribution of elements in oil fired flyash. These distributions of anthropogenic source elements, such as Zn, Ni, Cu, and Cr were higher predominately than those of natural source elements. And the higher distribution was found in the density range of $2.2 \sim 2.9g.cm^{-3}$ from the density distribution of elements in coal and soft-coal fired flyash. These distributions showed similar patterns to soil. But anthropogenic source elements somewhat predominated at the density ranges of $1.3 \sim 2.2g.cm{-3} and 2.9g.cm^{-3}$ to soil. Therefore the higher distribution of anthropogenic source elements in the density ranges of $1.3 \sim 2.2g.cm^{-3} and 2.9g.cm^{-3}$ was considered as anthropogenic origin.

• Polymer(Korea)
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• v.24 no.1
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• pp.1-7
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• 2000

The ACF/PP-g-AAc copolymers were synthesized by the irradiational grafting of acrylic acid onto ACF/PP fabric. The synthesis of copolymer was evidenced by the bands at 1720, 3600~3100 $cm^{-1}$ / on FT-IR spectrum. After the adsorption of metal ions on ACF/PP-g-AAc copolymers, the morphology with the small deposits on the fiber surface were observed by SEM. The optimal time for the metal ion adsorption equilibrium on ACF/PP-g-AAc copolymers was 24 hrs and their adsorption capacities increased in the order of Mn$^{2+}$>Cu$^{2+}$>Co$^{2+}$>Ni$^{2+}$. The adsorption capacities of ACF/PP-g-AAc copolymers were invariable after more than 10 times of regeneration.eration.

• Journal of environmental and Sanitary engineering
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• v.9 no.2
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• pp.8-23
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• 1994

During the period from Mar., 1991 to Feb., 1992 66 tSP samples were collected by Hi volume air sampler at 1 sampling site in Seoul and the amount of concentration of 21 components(SO$_{4}$$^{2-}$, NO$_{3}$$^{-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Al, Ba, Ca, Cd, Cr, Cu, Fe, It Mg, Mn, Na, Ni, Pt Si, Ti, Zn, Zr ) were measured. And monthly and seasonal variation were surveyed and the principal component analysis( PCA ) were carried out with respect to these amount of pollutants, minimum of visibility and radiation on a horizontal surface. The total amount of soluble ion in water was high in order o(SO$_{4}$$^{2-}$> NO$_{3}$$^{-}$> N%'>Cl$^{-}$ and metal ion was high in order of Na> Ca>Si> Fe> Al> K> Mg> Zn> Pb> Cu>Ti> Mn > Ba> Cr> Zr> Ni> Cd. There was Seasonal variation in concentration for SO$_{4}$$^{2-}$, NH$_{4}$$^{+}$, Cl$^{-}$, Na, Al, Ca, Bt Mg, Fe and Si. It was assumed that the components of the highest concentration on April were depend on yellow sand and the frequency of wind velocity and direction. As the results of PCA, the amount of pollution components was able to characterized with two principal components(Z$_{1}$, Z$_{2}$ ). The first principal components Z$_{1}$ was considered to be a factor indicating the pollutants originated from natural generation and The second principal components Z$_{2}$ was considered to be a factor indicating the pollutants originated from human work. The monthly concentration of pollutants in ISP, minimum of visibility and radiation on a horizontal surface was possible to evaluate by the use of these two principal components Z$_{1}$ and Z$_{2}$ .

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.547-555
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• 2014

Objective: This study was conducted to investigate the association between subjective distress symptoms and argon welding among workers in Gyeongnam Province shipyard. Method: 31 argon and 29 non-argon welding workers were selected as study subjects in order to measure concentrations of personal dust, welding fumes and other hazardous materials such as ZnO, Pb, Cr, FeO, MnO, Cu, Ni, $TiO_2$, MgO, NO, $NO_2$, $O_3$, $O_2$, $CO_2$, CO and Ar. An interviewer-administered questionnaire survey was also performed on the same subjects. The items queried were as follows: age, height, weight, working duration, welding time, welding rod amounts used, drinking, smoking, and rate of subjective distress symptoms including headache and other symptoms such as fever, vomiting and nausea, metal fume fever, dizziness, tingling sensations, difficulty in breathing, memory loss, sleep disorders, emotional disturbance, hearing loss, hand tremors, visual impairment, neural abnormality, allergic reaction, runny nose and stuffiness, rhinitis, and suffocation. Statistical analysis was performed using SPSS software, version 18. Data are expressed as the mean ${\pm}SD$. An ${\chi}^2$-test and a normality test using a Shapiro wilk test were performed for the above variables. Logistic regression analysis was also conducted to identify the factors that affect the total score for subjective distress symptoms. Result: An association was shown between welding type (argon or non-argon welding) and the total score for subjective distress symptoms. Among the rate of complaining of subjective distress symptoms, vomiting and nausea, difficulty breathing, and allergic reactions were all significantly higher in the argon welding group. Only the concentration of dust and welding fumes was shown to be distributed normally after natural log transformation. According to logistic regression analysis, the correlations of working duration and welding type (argon or non-argon) between the total score of subjective distress symptoms were found to be statistically significant (p=0.041, p=0.049, respectively). Conclusion: Our results suggest that argon welding could cause subjective distress symptoms in shipyard workers.