• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.4
• /
• pp.587-593
• /
• 1995

Lectin was purified by using $(NH_4)_2SO_4$, DEAE-cellulose ion-exchange chromatography and Sephadex G-150 column chromatography from Alismatis Rhizoma(AR). The specific activity of AR lectin was 50, 441units/mg, and purification folds were 114. The AR lectin agglutinated human erythrocytes of all types(A, B, O, AB). The molecular weight of AR lectin was estimated about 90, 500 daltons by gel filtration and each subunits were 42,000, 27,000 and 22,500 daltons on SDS-PAGE respectively. The hemagglutinating activity of the lectin was inhibited by sialic acid, glucose, ribose, galactose, sucrose, and lactose. It was also inhibited by cations such as $Hg^{++},\;Fe^{++},\;Cu^{++}\;and\;Pb^{++}$.

• Journal of the Korean Chemical Society
• /
• v.15 no.2
• /
• pp.49-54
• /
• 1971

It is shown that the impurities of Cu(II), Pb(II), Zn(II) and Ag(I) in Bismuth metal and the components of Pb(II), Zn(II) and Sn(IV) in Bismuth alloy are separated into their components from each other by elutions through $3.14cm^2{\times}10cm$ cation exchange resin, $Dowex\;50w\;{\times}\;8$ (100~200 mesh), column with the mixed solutions of HAc and NaAc as the eluents. The elution curve of Fe(III) has a long tailing and is not separated quantitatively from Bi(III). The eluents used for this separation are as follows; 1M HAc + 0.1M NaAc (pH 3.36) for Fe(III) and Bi (III). 0.3M HAc + 0.3M NaAc (pH 4.70) for Cu(II), Pb(II) and Zn(II). 0.5M HAc + 0.5M NaAc (pH4.70) for Ag(I) and Sn(IV). The analysis of cations eluted are carried out by spectrophotometry and EDTA titrimetry. Their recoveries are more than 99%.

• Journal of the Korean earth science society
• /
• v.42 no.4
• /
• pp.412-424
• /
• 2021

Understanding the distribution of heavy metals in sediment is necessary because labile heavy metals can partition into the water column and bioaccumulate in aquatic organisms. Here we investigated six heavy metals (Co, Cu, Mn, Ni, Pb, and Zn) in sediment cores using a five-step sequential leaching method to examine the occurrence of heavy metals in the sediment. The results showed that all elements, except Mn, are depleted in the exchangeable and carbonate fractions. However, heavy metal concentrations are much higher in the Fe-Mn oxide and organic matter fractions, especially for Cu, indicating enrichment in the organic matter fraction. Furthermore, contamination parameters (contamination factor and geoaccumulation index) indicate that Mn contamination is high, primarily derived from anthropogenic sources, presenting a potential risk to ecosystems in the Nakdong River.

• Journal of the Korean Chemical Society
• /
• v.58 no.3
• /
• pp.283-288
• /
• 2014

A column solid phase extraction procedure based on modified polyurethane foam (PUF) by a newly synthesized Schiff base ionophore, named 2,2'-{iminobis[propane-3,1-diylnitrilo(1E)prop-1-yl-1-ylidene]}diphenol, was developed for preconcentration step of trace amounts determination of copper ions in water samples by atomic absorption flame spectroscopy. The influence of parameters on the adsorption process such as sample pH, amount of modified PUF packed in the column, type and volume of stripping reagent and its flow rate were investigated and optimized. Under optimum experimental conditions, the calibration graph was linear in a relatively wide range ($0.005-210{\mu}g/ml$) with a limit of detection $0.002{\mu}g/ml$ of copper. The proposed method allows achieving to a concentration factor of >133. The capacity of a column (1.6 cm i.d.) packed by 6 g of PUF modified by 12 mg of the Schiff base was found to be $247.7({\pm}2.1){\mu}g$ of copper. It was found that the adsorption process was highly selective towards copper ions with respect to some associated metal ions. The presented procedure was successfully applied for determination of copper in some water samples.

• Journal of Soil and Groundwater Environment
• /
• v.18 no.7
• /
• pp.32-40
• /
• 2013

This study was objected to evaluate the potential impact on the groundwater environment of the coal bottom ash used as fill materials on the land surface. From four coal-fired power plants, bottom-ashes were collected and analyzed through sequential extraction and column leaching tests following the meteoric water mobility procedure. The column tests shown leaching heavy metals including Pb, As, B, Cu, Zn, Mn, Ni, Ba, Sr, Sb, V, Cr, Mo, and Hg. The relatively high concentrations of B, Sr, Ba, and V in leachate were attributed to both the higher concentrations in the bottom ash and the relatively higher portion of leachable state, sorbed state, of metals. Bottom-ash samples from the D-plant only show high leaching potential of sulfate ($SO_4$), probably originated from the coal-combustion process, called the Fluidized Bed Combustion. Consequently, to manage recycling bottom ashes as fill materials, an evaluation system should be implemented to test the leaching potentials of metals from the ashes considering the absolute amount of metals and their state of existence in ashes, and the coal-combustion process.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.6 no.4
• /
• pp.29-42
• /
• 1986

This study is an experimental research on the adsorption capacity and the adsorption system utilizing Discarded Automotive Tires(DAT) and Powdered or Granular Activated Carbon(PAC or GAC) for the removal of heavy metals, Ag(I), Cd(II), Cu(II), Zn(II). Batch shaking test was conducted to determine the adsorption capacity of DA T and PAC in removing the heavy metals from aqueous wastes; and laboratory-scale column experiment was performed to present design factors affecting the optimum design of adsorption column with DAT and GAC, through the concept of Bed Deph/Service Time(BDST). As results, DAT has been proven to be a good adsorbent will its adsorption capacity not falling behind PAC or GAC. Factors affecting heavy metals removals were amount of adsorbents, initial concentrations, pH and so on. BDST equations were compared with values presented by the breakthrough data from adsorption system.

• Journal of Pharmaceutical Investigation
• /
• v.37 no.3
• /
• pp.179-186
• /
• 2007

A simple, sensitive and selective liquid chromatographic/tandem mass spectrometric method (LC-MS/MS) was developed and validated for doxifluridine and 5-fluorouracil (5-FU) quantification in dog heparinized plasma. Sample preparation was based on liquid-liquid extraction using a mixture of isopropanol/ethyl acetate (1/9 v/v) to extract doxifluridine, 5-FU and 5-chlorouracil (5-CU, an internal standard) from plasma. Chromatography was performed on a C-18 analytical column and the retention times were 2.7, 1.5 and 1.7 min for doxifluridine, 5-FU and 5-CU, respectively with shorter analysis time within 5 min than previously reported methods. The ionization was optimized using ESI negative mode and selectivity was achieved by tandem mass spectrometric analysis by multiple reaction monitoring (MRM) using the transformations of m/z 244.8>107.6, 129.0>42.0 and 144.9>42.1 for doxifluridine, 5-FU and 5-CU, respectively. The achieved low limit of quantification was 20.0 ng/mL and the assay exhibited linear range of 20-2000 ng/mL ($R^2>0.99957$ for doxifluridine and $R^2>0.99857$ for 5-FU), using $100{\mu}L$ of plasma. Accuracy and precision of quality control samples for both doxifluridine and 5-FU met KFDA and FDA Guidance criteria of 15% for accuracy with coefficients of variation less than 15%. This method demonstrated adequate sensitivity, specificity, accuracy, precision and stability to support the simultaneous analysis of doxifluridine and 5-FU in dog plasma samples in pharmacokinetic and bioequivalence studies.

• Ocean and Polar Research
• /
• v.25 no.4
• /
• pp.447-457
• /
• 2003

In order to understand the distribution of changes of geochemical characteristics in surface sediments according to various environmental changes around the artificial Lake Shihwa, surface sediments were sampled at $13{\sim}15$ sites form 1997 to 1999 and analyzed by C/S analyzer, ICP/MS and AAS. The average $S/C_{org}$ ratio was 0.35 in the surface sediments, which is similar to 0.36, the characteristic ratio of marine sediments. Heavy metal contents and enrichment factors in the surface sediments tended to be decreasing from the head to the mouth of the Lake Shihwa. With the deposition of fine-grained sediments in the central part of lake, anoxic water column induced the sulfides compounds with Cu, Cd and Zn. Metals such as Al, Fe, Cr, Co, Ni, Cu, Zn and Cd except for Mn and Pb showed relatively high correlation coefficients among them. The contents of Cr, Co, Ni, Cu, Zn and Cd in the surface sediments of the lake were two to five times higher than those in the lake before dike construction and also in outer part of the dike. These are mainly due to the Input of untreated industrial and municipal waste-waters into the lake, and the accumulation of heavy metals by limitation of physical mixing. Although metal contents of the surface sediments at the sites near the water-gate due to outer seawater inflow tended to be lower than those during the desalination, heavy metals were deposited in areas around the new industrial complex in the evidence of spatial distribution of heavy metals in the sediments. This is mainly due to the input of untreated waste-waters from tributaries.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.1
• /
• pp.25-31
• /
• 1997

Antioxidative activity of daidzin and puerarin isolated from Puerariae radix against oxidation of low density lipoprotein(LDL) was investigated. The concentration of daidzin at 100$\mu\textrm{g}$/$m\ell$ and puerarin at 60$\mu\textrm{g}$/$m\ell$ inhibited Cu$^{2+}$-mediated oxidation of LDL almost completely. The electrophoretic mobility of oxidized LDL by addition of daidzin(100$\mu\textrm{g}$/$m\ell$) and puerarin(60$\mu\textrm{g}$/$m\ell$) was faster than that of native LDL, but slower than that of oxidized LDL. The oxidized LDL induced by J774 or macrophage was inhibited strongly in the presence of 100$\mu\textrm{g}$/$m\ell$ daidzin and 60$\mu\textrm{g}$/$m\ell$ Puerarin. The formation of conjugated dienes in the oxidized LDL was strongly inhibited by 100$\mu\textrm{g}$/$m\ell$ daidzin and 60$\mu\textrm{g}$/$m\ell$ puerarin.n.

• Journal of the Korean Chemical Society
• /
• v.25 no.4
• /
• pp.275-282
• /
• 1981

A simple semiquantitative procedure was developed for the determination of sub-ppm level of chromium(VI) in aquatic samples by using an analytical micro-column packed with diphenylcarbazide(DPC) gel beads. DPC gel beads were prepared by swelling XAD-2 resin(115∼150 mesh in dry condition) in ethanol for 10min, packing into a glass column(1.5 mm bore, 65nm length) and adsorbing 1ml of ethanol solution of $2{\times}10^{-3}M$ DPC for 20min at room temperature. When 0.5ml of ethanol solution containing chromium(VI) was passed through the DPC gel column for 40min, the original white color of the reagent gel turned to red-violet from the up-stream of the column. As the length of colored band was proportional to the total amount of chromium(VI) in the sample solution passed through the column, the concentration of chromium(VI) could be determined from the calibration line which had been prepared by using the standard solution. Chromium(VI) ion as small as from 0.1 to 0.8 ppm could be determined with ${\pm}5{\sim}{\pm}15{\%}$ relative errors. Since other interfering cations were few, 100-fold excess of Fe(III), 50-fold excess of Cu(II) could be masked with EDTA. This method was successfully applied to the analysis of chromium(VI) in industrial effluents.